阅读说明：本技术 用于电子装置中的聚合物 (Polymers for use in electronic devices ) 是由 V·V·戴夫 于 2019-06-19 设计创作，主要内容包括：公开了一种聚酰亚胺膜,其中所述聚酰亚胺具有至少100,000的重均分子量,并且包含式(V)的重复单元结构。在式(V)中：R~a在每次出现时是相同或不同的,并且表示一个或多个四羧酸组分残基；并且R~b在每次出现时是相同或不同的,并且表示一个或多个芳香族二胺残基,其中30-100mol％的R~b具有式(II)或式(III)。在式(II)和式(III)中：R~1和R~2是相同或不同的,并且是F、R_f、或OR_f；R_f是C_(1-3)全氟烷基；并且*表示附接点。(A polyimide film is disclosed, wherein the polyimide has a weight average molecular weight of at least 100,000 and comprises a repeating unit structure of formula (V). In formula (V): r a Is the same or different at each occurrence and represents one or more tetracarboxylic acid component residues; and R is b Is the same or different at each occurrence and represents one or more aromatic diamine residues wherein 30 to 100 mole% of R b Has formula (II) or formula (III). In formula (II) and formula (III): r 1 And R 2 Are the same or different and are F, R f OR OR f ；R f Is C 1‑3 A perfluoroalkyl group; and denotes the attachment point.)

1. A liquid composition having a solids content of at least 10 wt% and a viscosity of at least 3000cps, the composition comprising

(a) Polyamic acid having repeating unit structure of formula I

Wherein:

R^ais the same or different at each occurrence and represents one or more tetracarboxylic acid component residues; and is

R^bIs the same or different at each occurrence and represents one or more aromatic diamine residues;

wherein 30 to 100 mol% of R^bHaving formula II or formula III

Wherein:

R¹and R²Are identical orIs different and is selected from the group consisting of F, R_fAnd OR_fA group of (a);

R_fis C_1-3A perfluoroalkyl group; and is

Denotes the attachment point;

wherein R is¹And R²Both adjacent to the attachment point; and

(b) a high boiling point aprotic solvent.

2. The composition of claim 1, wherein R^bRepresents a residue of a diamine selected from the group consisting of compounds IV-A to IV-F

3. The composition of claim 1, wherein R^aRepresents two or more tetracarboxylic acid component residues, wherein the tetracarboxylic acid component is selected from the group consisting of BPDA, 6FDA, PMDA, and CBDA.

4. A polyimide film having a weight average molecular weight of at least 100,000 and comprising a repeating unit structure of formula V

Wherein:

R^ais the same or different at each occurrence and represents one or more tetracarboxylic acid component residues; and is

R^bIs the same or different at each occurrence and represents one or more aromatic diamine residues;

wherein 30 to 100 mol% of R^bHaving formula II or formula III

Wherein:

R¹and R²Are the same or different and are selected from the group consisting of F, R_fAnd OR_fA group of (a);

R_fis C_1-3A perfluoroalkyl group; and is

Denotes the attachment point;

wherein R is¹And R²Both adjacent to the attachment point;

and further wherein the polyimide film is prepared according to a process comprising, in order and without repetition:

applying a polyamic acid solution comprising one or more tetracarboxylic acid components and one or more diamine components in a high boiling aprotic solvent to a substrate;

soft baking the coated substrate;

the soft baked coated substrate is treated at a plurality of preselected temperatures at a plurality of preselected time intervals.

5. The polyimide film of claim 4, wherein the highest preselected temperature is 375 ℃.

6. The polyimide film of claim 5, wherein the process is conducted under an inert atmosphere.

Technical Field

The present disclosure relates to novel polymeric compounds. The present disclosure further relates to methods for preparing such polymeric compounds and electronic devices having at least one layer comprising these materials.

Background

Materials used in electronic applications often have stringent requirements with respect to their structural, optical, thermal, electronic and other properties. As the number of commercial electronic applications continues to increase, the breadth and specificity of desired properties requires innovation of materials with new and/or improved properties. Polyimides represent a class of polymeric compounds that have been widely used in a variety of electronic applications. They can serve as flexible substitutes for glass in electronic display devices, provided they have suitable properties. These materials are useful as components of liquid crystal displays ("LCDs"), where their modest electrical power consumption, light weight, and layer flatness are key characteristics for practical utility. Other uses in electronic display devices where such parameters are preferentially set include device substrates, substrates for color filters, cover films, touch screen panels, and the like.

Many of these components are also important in the construction and operation of organic electronic devices having organic light emitting diodes ("OLEDs"). OLEDs are promising for many display applications due to high power conversion efficiency and applicability to a wide range of end uses. They are increasingly used in cell phones, tablet devices, handheld/laptop computers, and other commercial products. In addition to low power consumption, these applications require displays with high information content, full color, and fast video rate response times.

Polyimide films typically have sufficient thermal stability, high glass transition temperature, and mechanical toughness to be considered for such uses. Moreover, polyimides do not typically produce haze when subjected to repeated flexing, so they are often preferred in flexible display applications over other transparent substrates like polyethylene terephthalate (PET) and polyethylene naphthalate (PEN).

However, the use of conventional amber colored polyimides in some display applications such as color filters and touch screen panels is hampered by the priority of optical transparency. Furthermore, polyimides are generally hard, highly aromatic materials; and as the film/coating is formed, the polymer chains tend to orient in the plane of the film/coating. This results in a difference in refractive index (birefringence) between the parallel and perpendicular directions of the film, producing a light retardation that may adversely affect display performance. If additional uses of polyimides are sought in the display market, solutions are needed that maintain their desirable properties while improving their optical clarity and reducing amber color and birefringence leading to light retardation.

There is therefore a continuing need for polymeric materials suitable for use in electronic devices.

Disclosure of Invention

A liquid composition having a solids content of at least 10 wt% and a viscosity of at least about 3000cps is provided, the composition comprising

(a) Polyamic acid having repeating unit structure of formula I

Wherein:

R^ais the same or different at each occurrence and represents one or more tetracarboxylic acid component residues; and is

R^bThe same or different at each occurrence,and represents one or more aromatic diamine residues;

wherein 30 to 100 mol% of R^bHaving formula II or formula III

Wherein:

R¹and R²Are the same or different and are selected from the group consisting of F, R_fAnd OR_fA group of (a);

R_fis C_1-3A perfluoroalkyl group; and is

Denotes the attachment point;

wherein R is¹And R²Both adjacent to the attachment point; and

(b) a high boiling point aprotic solvent.

Further provided is a polyimide film, wherein the polyimide has a number average molecular weight of at least 100,000 and comprises a repeating unit structure of formula V

Wherein:

R^ais the same or different at each occurrence and represents one or more tetracarboxylic acid component residues; and is

R^bIs the same or different at each occurrence and represents one or more aromatic diamine residues;

wherein 30 to 100 mol% of R^bHaving formula II or formula III

Wherein:

R¹and R²Are the same or different and are selected from the group consisting of F, R_fAnd OR_fA group of (a);

R_fis C_1-3A perfluoroalkyl group; and is

Denotes the attachment point;

wherein R is¹And R²Both adjacent to the attachment point;

and further wherein the polyimide film is prepared according to a process comprising, in order and without repetition:

applying a polyamic acid solution comprising one or more tetracarboxylic acid components and one or more diamine components in a high boiling aprotic solvent to a substrate;

soft baking the coated substrate;

the soft baked coated substrate is treated at a plurality of preselected temperatures at a plurality of preselected time intervals.

Further provided is a polyimide film, wherein the polyimide has a weight average molecular weight of at least 100,000 and comprises a repeating unit structure of formula V

Wherein:

R^ais the same or different at each occurrence and represents one or more tetracarboxylic acid component residues; and is

R^bIs the same or different at each occurrence and represents one or more aromatic diamine residues;

wherein 30 to 100 mol% of R^bHaving formula II or formula III

Wherein:

R¹and R²Are the same or different and are selected from the group consisting of F, R_fAnd OR_fA group of (a);

R_fis C_1-3A perfluoroalkyl group; and is

Denotes the attachment point;

wherein R is¹And R²Both adjacent to the attachment point;

and further wherein the polyimide film is prepared according to a process comprising, in order and without repetition:

applying a polyamic acid solution comprising one or more tetracarboxylic acid components and one or more diamine components in a high boiling aprotic solvent to a substrate;

soft baking the coated substrate;

the soft baked coated substrate is treated at a plurality of preselected temperatures at a plurality of preselected time intervals.

There is further provided a flexible substitute for glass in an electronic device, wherein the flexible substitute for glass is the polyimide film described above.

There is further provided an electronic device having at least one layer comprising the polyimide film described above.

Further provided is an organic electronic device, such as an OLED, wherein the organic electronic device contains a flexible substitute for glass as disclosed herein.

The foregoing general description and the following detailed description are exemplary and explanatory only and are not restrictive of the invention, as defined in the appended claims.

Drawings

Embodiments are illustrated in the drawings to improve understanding of the concepts as presented herein.

Fig. 1 includes an illustration of one example of a polyimide film that can serve as a flexible substitute for glass.

Fig. 2 includes an illustration of one example of an electronic device including a flexible substitute for glass.

Skilled artisans appreciate that elements in the figures are illustrated for simplicity and clarity and have not necessarily been drawn to scale. For example, the dimensions of some of the objects in the figures may be exaggerated relative to other objects to help to improve understanding of embodiments.

Detailed Description

A polyamic acid having formula I is provided as described in detail below.

Further provided is a composition comprising (a) a polyamic acid having formula I and (b) a high boiling aprotic solvent.

There is further provided a polyimide as described in detail below, the repeat unit of the polyimide having the structure in formula IV.

Further provided are one or more methods for making a polyimide membrane, wherein the polyimide membrane has a repeat unit of formula IV.

Further provided is a flexible substitute for glass in an electronic device, wherein the flexible substitute for glass is a polyimide film having a repeating unit of formula IV.

Further provided is an electronic device having at least one layer comprising a polyimide film having a repeat unit of formula IV.

Further provided is an organic electronic device, such as an OLED, wherein the organic electronic device contains a flexible substitute for glass as disclosed herein.

Many aspects and embodiments have been described above and are merely exemplary and non-limiting. Upon reading this specification, skilled artisans will appreciate that other aspects and embodiments are possible without departing from the scope of the invention.

Other features and benefits of any one or more embodiments will be apparent from the detailed description below and from the claims. This detailed description first proposes a definition and clarification of terms, followed by a liquid composition, a polyimide, a method for producing a polyimide film, an electronic device, and finally an example.

1. Definition and clarification of terms

Before addressing details of the following examples, some terms are defined or clarified.

R, R as used in the definition and clarification of terms^a、R^bR', R "and any other variables are generic names and may be the same or different from those defined in the formula.

The term "alignment layer" is intended to mean an organic polymer layer in a Liquid Crystal Device (LCD) that aligns the molecules closest to each plate as a result of its rubbing onto the LCD glass in one preferred direction during the LCD manufacturing process.

As used herein, the term "alkyl" includes both branched and straight chain saturated aliphatic hydrocarbon groups. Unless otherwise indicated, the term is also intended to include cyclic groups. Examples of alkyl groups include methyl, ethyl, propyl, isopropyl, isobutyl, sec-butyl, tert-butyl, pentyl, isopentyl, neopentyl, cyclopentyl, hexyl, cyclohexyl, isohexyl and the like. The term "alkyl" further includes both substituted and unsubstituted hydrocarbon groups. In some embodiments, the alkyl groups may be mono-, di-, and tri-substituted. An example of a substituted alkyl group is trifluoromethyl. Other substituted alkyl groups are formed from one or more of the substituents described herein. In certain embodiments, the alkyl group has 1 to 20 carbon atoms. In other embodiments, the group has 1 to 6 carbon atoms. The term is intended to include heteroalkyl groups. The heteroalkyl group may have 1-20 carbon atoms.

The term "aprotic" refers to a class of solvents that lack an acidic hydrogen atom and therefore cannot act as a hydrogen donor. Common aprotic solvents include alkanes, carbon tetrachloride (CCl4), benzene, Dimethylformamide (DMF), N-methyl-2-pyrrolidone (NMP), dimethylacetamide (DMAc), and the like.

The term "aromatic compound" is intended to mean an organic compound comprising at least one unsaturated cyclic group having 4n +2 delocalized pi electrons. The term is intended to encompass both aromatic compounds, which have only carbon and hydrogen atoms, and heteroaromatic compounds in which one or more carbon atoms within the cyclic group have been replaced by another atom, such as nitrogen, oxygen, sulfur, and the like.

The term "aryl" or "aryl group" refers to a moiety formed by the removal of one or more hydrogens ("H") or deuterons ("D") from an aromatic compound. The aryl group can be a single ring (monocyclic) or have multiple rings (bicyclic, or more) fused together or covalently linked. "Hydrocarbon aryl" groups have only carbon atoms in one or more aromatic rings. "heteroaryl" has one or more heteroatoms in at least one aromatic ring. In some embodiments, the hydrocarbon aryl group has 6 to 60 ring carbon atoms; in some embodiments, from 6 to 30 ring carbon atoms. In some embodiments, heteroaryl groups have 4 to 50 ring carbon atoms; in some embodiments, from 4 to 30 ring carbon atoms.

The term "alkoxy" is intended to mean the group-OR, wherein R is alkyl.

The term "aryloxy" is intended to mean the radical-OR, where R is aryl.

Unless otherwise indicated, all groups may be substituted or unsubstituted. Optionally substituted groups, such as but not limited to alkyl or aryl, may be substituted with one or more substituents which may be the same or different. Suitable substituents include alkyl, aryl, nitro, cyano, -N (R') (R)^”) Halogen, hydroxy, carboxy, alkenyl, alkynyl, cycloalkyl, heteroaryl, alkoxy, aryloxy, heteroaryloxy, alkoxycarbonyl, perfluoroalkyl, perfluoroalkoxy, arylalkyl, silyl, siloxy, siloxane, thioalkoxy, -S (O)₂-, -C (═ O) -N (R ') (R'), (R ') (R') N-alkyl, (R ') (R') N-alkoxyalkyl, (R ') (R') N-alkylaryloxyalkyl, -S (O)_s-aryl (wherein s ═ 0-2), or-s (o)_s-heteroaryl (wherein s ═ 0-2). Each R' and R "is independently an optionally substituted alkyl, cycloalkyl or aryl group. R' and R ", together with the nitrogen atom to which they are bound, may form a ring system in certain embodiments. The substituent may also be a crosslinking group.

The term "amine" is intended to mean a compound containing a basic nitrogen atom with a lone pair of electrons. The term "amino" refers to the functional group-NH₂-NHR or-NR₂Wherein R is the same or different at each occurrence and can be an alkyl group or an aryl group. The term "diamine" is intended to meanA compound containing two basic nitrogen atoms with associated lone pair electrons. The term "aromatic diamine" is intended to mean an aromatic compound having two amino groups. The term "bent diamine" is intended to mean a diamine in which two basic nitrogen atoms and associated lone pair electrons are asymmetrically disposed about the center of symmetry of the corresponding compound or functional group, such as m-phenylenediamine:

the term "aromatic diamine residue" is intended to mean a moiety bonded to two amino groups in an aromatic diamine. The term "aromatic diisocyanate residue" is intended to mean a moiety bonded to two isocyanate groups in an aromatic diisocyanate compound. This is further explained below.

The terms "diamine residue" and "diisocyanate residue" are intended to mean a moiety bonded to two amino groups or two isocyanate groups, respectively, wherein the moiety may be aromatic or aliphatic.

The term "b" is intended to mean the b axis representing the yellow/blue opponent color in the CIELab color space. Yellow is represented by positive b values and blue by negative b values. The measured b-value may be affected by the solvent, in particular because solvent selection may affect the colour measured on materials exposed to high temperature processing conditions. This may occur as a result of the inherent characteristics of the solvent and/or characteristics associated with low levels of impurities contained in the various solvents. The particular solvent is typically pre-selected to achieve the b values desired for a particular application.

The term "birefringence" is intended to mean the difference in refractive index in different directions in a polymer film or coating. The term generally refers to the difference between the x-or y-axis (in-plane) and z-axis (out-of-plane) refractive indices.

The term "charge transport," when referring to a layer, material, member, or structure, is intended to mean that such layer, material, member, or structure facilitates the migration of such charges through the thickness of such layer, material, member, or structure with relative efficiency and small charge loss. The hole transport material favors positive charge; the electron transport material favors negative charges. Although a light emitting material may also have some charge transport properties, the term "charge transport layer, material, member, or structure" is not intended to include a layer, material, member, or structure whose primary function is to emit light.

The term "compound" is intended to mean an uncharged substance consisting of molecules further including atoms, wherein the atoms cannot be separated from their corresponding molecules by physical means without breaking chemical bonds. The term is intended to include oligomers and polymers.

The term "coefficient of linear thermal expansion (CTE or a)" is intended to refer to a parameter that defines the amount of expansion or contraction of a material with temperature. It is expressed as a change in length per degree celsius and is typically expressed in units of μm/m/° c or ppm/° c.

α＝(ΔL/L₀)/ΔT

The measured CTE values disclosed herein are generated via known methods during the first or second heating scan. Understanding the relative expansion/contraction characteristics of materials can be an important consideration in the manufacture and/or reliability of electronic devices.

The term "dopant" is intended to refer to a material within a layer that includes a host material that alters one or more electronic properties or one or more target wavelengths of radiation emission, reception, or filtering of the layer as compared to the one or more electronic properties or one or more wavelengths of radiation emission, reception, or filtering of the layer in the absence of such material.

The term "electroactive" when referring to a layer or material is intended to mean a layer or material that electronically facilitates operation of the device. Examples of electroactive materials include, but are not limited to, materials that conduct, inject, transport, or block a charge, which can be an electron or a hole, or a material that emits radiation or exhibits a change in the concentration of electron-hole pairs upon receiving radiation. Examples of inactive materials include, but are not limited to, planarization materials, insulating materials, and environmental barrier materials.

The term "tensile elongation" or "tensile strain" is intended to mean the percentage increase in length that occurs in a material before the material breaks under an applied tensile stress. It can be measured, for example, by ASTM method D882.

The prefix "fluoro" is intended to mean that one or more hydrogens in the group have been replaced with fluorine.

The term "glass transition temperature (or T)_g) "is intended to mean the temperature at which a reversible change occurs in an amorphous polymer or in amorphous regions of a semi-crystalline polymer, wherein the material suddenly changes from a hard, glassy or brittle state to a flexible or elastic state. Under a microscope, glass transition occurs when normally coiled, stationary polymer chains become free to rotate and can move past each other. T can be measured using Differential Scanning Calorimetry (DSC), thermomechanical analysis (TMA), or Dynamic Mechanical Analysis (DMA), or other methods_g。

The prefix "hetero" indicates that one or more carbon atoms have been replaced by a different atom. In some embodiments, the heteroatom is O, N, S, or a combination thereof.

The term "high boiling point" is intended to mean a boiling point above 130 ℃.

The term "host material" is intended to refer to a material to which a dopant is added. The host material may or may not have one or more electronic properties or capabilities to transmit, receive, or filter radiation. In some embodiments, the host material is present in a higher concentration.

The term "isothermal weight loss" is intended to mean a material property directly related to its thermal stability. It is typically measured at a constant target temperature via thermogravimetric analysis (TGA). Materials with high thermal stability typically exhibit very low isothermal weight loss percentages over a desired period of time at required use or processing temperatures, and thus can be used for applications at these temperatures without significant strength loss, outgassing, and/or structural changes.

The term "liquid composition" is intended to mean a liquid medium in which a material is dissolved to form a solution, a liquid medium in which a material is dispersed to form a dispersion, or a liquid medium in which a material is suspended to form a suspension or emulsion.

The term "substrate" is intended to refer to a foundation upon which one or more layers are deposited, for example, in the formation of an electronic device. Non-limiting examples include glass, silicon, and the like.

The term "1% TGA weight loss" is intended to mean the temperature at which 1% of the original polymer weight is lost due to decomposition (excluding absorbed water).

The term "optical retardation (or R)_TH) "is intended to mean the difference between the average in-plane refractive index and the out-of-plane refractive index (i.e., birefringence), which is then multiplied by the thickness of the film or coating. The optical delay is typically measured for light of a given frequency and reported in nanometers.

The term "organic electronic device" or sometimes "electronic device" is intended herein to refer to a device that includes one or more organic semiconductor layers or one or more materials.

The term "particle content" is intended to mean the number or count of insoluble particles present in a solution. The measurement of the particle content can be performed on the solution itself or on finished materials (sheets, films, etc.) made from those films. Various optical methods can be used to assess this property.

The term "photoactive" refers to a material or layer that emits light when activated by an applied voltage (as in a light emitting diode or chemical cell), emits light after absorbing photons (as in a down-converting phosphor device), or generates a signal in response to radiant energy and with or without an applied bias voltage (as in a photodetector or photovoltaic cell).

The term "polyamic acid solution" refers to a solution of a polymer containing amic acid units having the ability to cyclize intramolecularly to form an imide group.

The term "polyimide" refers to condensates resulting from the reaction of one or more difunctional carboxylic acid components with one or more primary diamines or diisocyanates. They contain the imide structure-CO-NR-CO-as a linear or heterocyclic unit along the backbone of the polymer backbone.

The term "satisfactory" when referring to a material property or characteristic is intended to mean that the property or characteristic meets all of the requirements/requirements of the material in use. For example, in the context of the polyimide membranes disclosed herein, an isothermal weight loss of less than 1% at 350 ℃ for 3 hours in nitrogen can be considered as a non-limiting example of "satisfactory" characteristics.

The term "soft bake" is intended to refer to a process commonly used in electronics manufacturing in which the coated material is heated to drive off the solvent and cure the film. Soft baking is usually carried out at a temperature of 90 to 110 ℃ on a hot plate or in an exhaust oven as a preparation step for the subsequent heat treatment of the coated layer or film.

The term "substrate" refers to a base material that may be rigid or flexible and may include one or more layers of one or more materials, which may include, but are not limited to, glass, polymer, metal, or ceramic materials, or combinations thereof. The substrate may or may not include electronic components, circuitry, or conductive members.

The term "siloxane" refers to the group R₃SiOR₂Si-, wherein R is the same or different at each occurrence and is H, C1-20 alkyl, fluoroalkyl, or aryl. In some embodiments, one or more carbons in the R alkyl group are replaced with Si.

The term "siloxy" refers to the group R₃SiO-, wherein R is the same or different at each occurrence and is H, C1-20 alkyl, fluoroalkyl, or aryl.

The term "silyl" refers to the group R₃Si-, wherein R is the same or different at each occurrence and is H, C1-20 alkyl, fluoroalkyl, or aryl. In some embodiments, one or more carbons in the R alkyl group are replaced with Si.

The term "spin coating" is intended to refer to a process for depositing a uniform thin film onto a flat substrate. Generally, a small amount of coating material is applied on the center of a substrate, which is rotated at a low speed or not rotated at all. The substrate is then rotated at a prescribed speed so as to uniformly spread the coating material by centrifugal force.

The term "laser particle counter test" refers to a method for evaluating the particle content of polyamic acid and other polymer solutions whereby a representative sample of the test solution is spin coated onto a5 "silicon wafer and soft baked/dried. The particle content of the films thus prepared is evaluated by any number of standard measurement techniques. Such techniques include laser particle detection and other techniques known in the art.

The term "tensile modulus" is intended to refer to a measure of the stiffness of a solid material, which defines the initial relationship between stress (force per unit area) and strain (proportional deformation) in a material such as a film. The unit commonly used is gigapascal (GPa).

The term "tetracarboxylic acid component" is intended to mean any one or more of the following: tetracarboxylic acid, tetracarboxylic monoanhydride, tetracarboxylic dianhydride, tetracarboxylic monoester, and tetracarboxylic diester.

The term "tetracarboxylic acid component residue" is intended to mean a moiety bonded to four carboxyl groups in the tetracarboxylic acid component. This is further explained below.

The term "transmittance" refers to the percentage of light of a given wavelength that impinges on the film that passes through the film so as to be detectable on the other side. Light transmittance measurements in the visible region (380nm to 800nm) are particularly useful for characterizing film color characteristics that are most important for understanding in-use properties of the polyimide films disclosed herein.

The term "yellowness index (or YI)" refers to the magnitude of yellowness relative to a standard. Positive values of YI indicate the presence and magnitude of yellow. Materials with negative YI appear bluish. Especially for polymerization and/or curing processes operating at high temperatures, it should also be noted that YI may be solvent dependent. For example, the magnitude of the color introduced using DMAC as a solvent may be different from the magnitude of the color introduced using NMP as a solvent. This may occur as a result of the inherent characteristics of the solvent and/or characteristics associated with low levels of impurities contained in the various solvents. The particular solvent is typically pre-selected to achieve the YI value desired for a particular application.

In structures where the substituent bonds shown below pass through one or more rings,

this means that the substituent R may be bonded at any available position on one or more rings.

The phrase "adjacent," when used in reference to a layer in a device, does not necessarily mean that one layer is immediately adjacent to another layer. On the other hand, the phrase "adjacent R groups" is used to refer to R groups in the formula that are immediately adjacent to each other (i.e., R groups on atoms that are bonded by a bond). Exemplary adjacent R groups are shown below:

in this specification, unless the context of usage clearly dictates otherwise or indicates to the contrary, where an embodiment of the inventive subject matter is stated or described as comprising, including, containing, having, consisting of or consisting of certain features or elements, one or more features or elements other than those explicitly stated or described may also be present in that embodiment. Alternative embodiments of the disclosed subject matter are described as consisting essentially of certain features or elements, wherein embodiment features or elements that would materially alter the principle of operation or the distinguishing characteristics of the embodiments are not present here. Another alternative embodiment of the subject matter described is described as consisting of certain features or elements, in which embodiment, or in insubstantial variations thereof, only the features or elements specifically stated or described are present.

Furthermore, unless expressly stated to the contrary, "or" means an inclusive or and not an exclusive or. For example, condition a or B is satisfied by any one of the following: a is true (or present) and B is false (or not present), a is false (or not present) and B is true (or present), and both a and B are true (or present).

Also, the use of "a/an" is used to describe elements and components described herein. This is done merely for convenience and to give a general sense of the scope of the invention. The description should be read to include one or at least one and the singular also includes the plural unless it is obvious that it is meant otherwise.

The group numbers corresponding to columns within the periodic Table of the elements use the convention "New Notation" as seen in the CRC Handbook of Chemistry and Physics [ Handbook of Chemistry and Physics ], 81 th edition (2000-2001).

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. Although methods and materials similar or equivalent to those described herein can be used in the practice or testing of embodiments of the present invention, suitable methods and materials are described below. All publications, patent applications, patents, and other references mentioned herein are incorporated by reference in their entirety, unless a specific passage is cited. In case of conflict, the present specification, including definitions, will control. In addition, the materials, methods, and examples are illustrative only and not intended to be limiting.

To the extent not described herein, many details regarding specific materials, processing acts, and circuits are conventional and may be found in textbooks and other sources within the organic light emitting diode display, photodetector, photovoltaic, and semiconductor component arts.

2. Liquid composition

There is provided a liquid composition having a solids content of at least 10 wt% and a viscosity of at least about 3,000cps (cps ═ centipoises), the composition comprising

(a) Polyamic acid having repeating unit structure of formula I

Wherein:

R^ais the same or different at each occurrence and represents one or more tetracarboxylic acid component residues; and is

R^bIs the same or different at each occurrence and represents one or more aromatic diamine residues;

wherein 30 to 100 mol% of R^bHaving formula II or formula III

Wherein:

R¹and R²Are the same or different and are selected from the group consisting of F, R_fAnd OR_fA group of (a);

R_fis C_1-3A perfluoroalkyl group; and is

Denotes the attachment point;

wherein R is¹And R²Both adjacent to the attachment point; and

(b) a high boiling point aprotic solvent.

This liquid composition is also referred to herein as a "polyamic acid solution".

In some embodiments of the liquid composition, the solids content is at least 12 wt%; in some embodiments, at least 15 wt%. In some embodiments, the solids content is 10-20 wt%.

In some embodiments of the liquid composition, the viscosity is at least about 5000 cps; and in some embodiments at least about 10,000 cps.

In some embodiments of formula I, R^aRepresents a single tetracarboxylic acid component residue.

In some embodiments of formula I, R^aRepresenting two tetracarboxylic acid component residuesAnd (4) a base.

In some embodiments of formula I, R^aRepresents three tetracarboxylic acid residues.

In some embodiments of formula I, R^aRepresents four tetracarboxylic acid residues.

In some embodiments of formula I, R^aRepresents one or more tetracarboxylic dianhydride residues.

Examples of suitable aromatic tetracarboxylic dianhydrides include, but are not limited to, pyromellitic dianhydride (PMDA), 3',4,4' -biphenyltetracarboxylic dianhydride (BPDA), 4,4' -oxydiphthalic anhydride (ODPA), 4,4' -hexafluoroisopropylidenediphthalic anhydride (6FDA), 3',4,4' -benzophenonetetracarboxylic dianhydride (BTDA), 3',4,4 '-diphenylsulfone tetracarboxylic dianhydride (DSDA), 4' -bisphenol-A dianhydride (BPADA), hydroquinone diphthalic anhydride (HQDEA), ethylene glycol bis (trimellitic anhydride) (TMEG-100), 4- (2, 5-dioxotetrahydrofuran-3-yl) -1,2,3, 4-tetrahydronaphthalene-1, 2-dicarboxylic anhydride (DTDA); 4,4' -bisphenol a dianhydride (BPADA), and the like, and combinations thereof. These aromatic dianhydrides may be optionally substituted with groups known in the art including alkyl, aryl, nitro, cyano, -N (R') (R)^”) Halogen, hydroxy, carboxy, alkenyl, alkynyl, cycloalkyl, heteroaryl, alkoxy, aryloxy, heteroaryloxy, alkoxycarbonyl, perfluoroalkyl, perfluoroalkoxy, arylalkyl, silyl, siloxy, siloxane, thioalkoxy, -S (O)₂-, -C (═ O) -N (R ') (R'), (R ') (R') N-alkyl, (R ') (R') N-alkoxyalkyl, (R ') (R') N-alkylaryloxyalkyl, -S (O)_s-aryl (where s ═ 0-2) or-s (o)_s-heteroaryl (wherein s ═ 0-2). Each R' and R "is independently an optionally substituted alkyl, cycloalkyl or aryl group. R' and R ", together with the nitrogen atom to which they are bound, may form a ring system in certain embodiments. The substituent may also be a crosslinking group.

In some embodiments of formula I, R^aRepresents one or more residues from a tetracarboxylic dianhydride selected from the group consisting of: PMDA, BPDA, 6FDA, and BTDA.

In some embodiments of formula IIn, R^aRepresents a PMDA residue.

In some embodiments of formula I, R^aRepresents a BPDA residue.

In some embodiments of formula I, R^aRepresents 6FDA residues.

In some embodiments of formula I, R^aRepresents a BTDA residue.

In some embodiments of formula I, R^aRepresents PMDA residues and BPDA residues.

In some embodiments of formula I, R^aRepresents PMDA residues and 6FDA residues.

In some embodiments of formula I, R^aRepresents PMDA residues and BTDA residues.

In some embodiments of formula I, R^aRepresenting BPDA residues and 6FDA residues.

In some embodiments of formula I, R^aRepresenting BPDA residues and BTDA residues.

In some embodiments of formula I, R^aRepresenting 6FDA residues and BTDA residues.

In formula I, 30 to 100 mol% of R^bRepresents a diamine residue having formula II or formula III as shown above. In some embodiments of formula I, 40 to 100 mol% R^bHas the formula II; in some embodiments, 50 to 100 mol%; in some embodiments, 60 to 100 mol%; in some embodiments, 70 to 100 mol%; in some embodiments, 80-100 mol%; in some embodiments, 90 to 100 mol%; in some embodiments, 100 mol%.

In some embodiments of formula II, R¹Is F.

In some embodiments of formula II, R¹Is C_1-3A perfluoroalkyl group; in some embodiments trifluoromethyl.

In some embodiments of formula II, R¹Is C_1-3A perfluoroalkoxy group; in some embodiments trifluoromethoxy.

In some embodiments of formula II, R¹＝R²。

In some embodiments of formula II, R¹≠R²。

For R in formula II¹All of the above-described embodiments of (A) apply equally to R in formula II²。

For R in formula II¹And R²All of the above-described embodiments of (A) apply equally to R in formula III¹And R²。

In some embodiments of formula I, R^bRepresents a residue of a diamine selected from the group consisting of compounds IV-A to IV-F shown below.

Diamines can be prepared as shown in the following scheme.

(1)

(2)

In some embodiments of formula I, R^bRepresents a diamine residue having formula II or formula III and at least one additional diamine residue.

In some embodiments of formula I, R^bRepresenting a diamine residue having formula II or formula III and one additional diamine residue.

In some embodiments of formula I, R^bRepresenting a diamine residue having formula II or formula III and two additional diamine residues.

In some embodiments of formula I, R^bRepresenting a diamine residue having formula II or formula III and three additional diamine residues.

In some embodiments, the additional aromatic diamine is selected from the group consisting of: p-phenylenediamine (PPD), 2 '-dimethyl-4, 4' -diaminobiphenyl (m-tolidine), 3 '-dimethyl-4, 4' -diaminobiphenyl (o-tolidine), 3 '-dihydroxy-4, 4' -diaminobiphenyl (HAB), 9 '-bis (4-aminophenyl) Fluorene (FDA), o-Tolidine Sulfone (TSN), 2,3,5, 6-tetramethyl-1, 4-phenylenediamine (TMPD), 2, 4-diamino-1, 3, 5-trimethylbenzene (DAM), 3',5,5 '-tetramethylbenzidine (3355TMB), 2' -bis (trifluoromethyl) benzidine (22TFMB or TFMB), 2-bis [4- (4-aminophenoxy) phenyl ] propane (BAPP), 4,4 '-Methylenedianiline (MDA), 4' - [1, 3-phenylenebis (1-methyl-ethylene) ] dianiline (Bis-M), 4'- [1, 4-phenylenebis (1-methyl-ethylene) ] dianiline (Bis-P), 4' -oxydianiline (4,4 '-ODA), M-phenylenediamine (MPD), 3,4' -oxydianiline (3,4 '-ODA), 3' -diaminodiphenyl sulfone (3,3 '-DDS), 4' -diaminodiphenyl sulfone (4,4 '-DDS), 4' -diaminodiphenyl sulfide (ASD), 2-Bis [4- (4-amino-phenoxy) phenyl ] sulfone (BAPS), 2, 2-bis [4- (3-aminophenoxy) -phenyl ] sulfone (m-BAPS), 1,4' -bis (4-aminophenoxy) benzene (TPE-Q), 1,3' -bis (4-aminophenoxy) benzene (TPE-R), 1,3' -bis (4-aminophenoxy) benzene (APB-133), 4' -bis (4-aminophenoxy) biphenyl (BAPB), 4' -Diaminobenzanilide (DABA), methylenebis (anthranilic acid) (MBAA), 1,3' -bis (4-aminophenoxy) -2, 2-Dimethylpropane (DANPG), 1, 5-bis (4-aminophenoxy) pentane (DA5MG), 2' -bis [4- (4-aminophenoxyphenyl) ] Hexafluoropropane (HFPP), 2, 2-Bis (4-aminophenyl) hexafluoropropane (Bis-A-AF), 2-Bis (3-amino-4-hydroxyphenyl) hexafluoropropane (Bis-AP-AF), 2-Bis (3-amino-4-methylphenyl) hexafluoropropane (Bis-AT-AF), 4 '-Bis (4-amino-2-trifluoromethylphenoxy) biphenyl (6BFBAPB), 3',5 '-tetramethyl-4, 4' -diaminodiphenylmethane (TMMDA), and the like, and combinations thereof.

In some embodiments of formula I, R^bRepresents a diamine residue having formula II or formula III and at least one additional diamine residue, wherein the additional aromatic diamine is selected from the group consisting of: PPD, 4 '-ODA, 3,4' -ODA, TFMB, Bis-A-AF, Bis-AT-AF, and Bis-P.

In some embodiments of formula I, the moiety derived from the monoanhydride monomer is present as an end capping group.

In some embodiments, these monoanhydride monomers are selected from the group consisting of phthalic anhydride and the like, as well as derivatives thereof.

In some embodiments, these monoanhydrides are present in an amount up to 5 mol% of the total tetracarboxylic acid composition.

In some embodiments of formula I, the moiety derived from the monoamine monomer is present as an end capping group.

In some embodiments, these monoamine monomers are selected from the group consisting of aniline and the like and derivatives thereof.

In some embodiments, the monoamines are present in an amount up to 5 mol% of the total amine composition.

In some embodiments, the polyamic acid has a weight average molecular weight (M) of greater than 100,000 based on gel permeation chromatography and polystyrene standards_W)。

In some embodiments, the polyamic acid has a weight average molecular weight (M) greater than 150,000 based on gel permeation chromatography and polystyrene standards_W)。

In some embodiments, the polyamic acid has a molecular weight (M) greater than 200,000 based on gel permeation chromatography and polystyrene standards_W)。

In some embodiments, the polyamic acid has a weight average molecular weight (M) of greater than 250,000 based on gel permeation chromatography and polystyrene standards_W)。

In some embodiments, the polyamic acid has a weight average molecular weight (M) greater than 300,000 based on gel permeation chromatography and polystyrene standards_W)。

In some embodiments, the polyamic acid has a weight average molecular weight (M) of 100,000 to 400,000 based on gel permeation chromatography and polystyrene standards_W)。

In some embodiments, the polyamic acid has a weight average molecular weight (M) of 200,000 to 400,000 based on gel permeation chromatography and polystyrene standards_W)。

In some embodiments, the polyamic acid has a weight average molecular weight (M) of 250,000 to 350,000 based on gel permeation chromatography and polystyrene standards_W)。

In some embodiments, the polyamic acid has a weight average molecular weight (M) of 200,000 to 300,000 based on gel permeation chromatography and polystyrene standards_W)。

Any of the above embodiments of polyamic acids can be combined with one or more of the other embodiments, as long as they are not mutually exclusive. For example, wherein R^aExamples of PMDA residues can be found in the case where R^bExample combinations having formula II.

In some embodiments, the high boiling aprotic solvent has a boiling point of 150 ℃ or higher.

In some embodiments, the high boiling aprotic solvent has a boiling point of 175 ℃ or higher.

In some embodiments, the high boiling aprotic solvent has a boiling point of 200 ℃ or higher.

In some embodiments, the high boiling aprotic solvent is a polar solvent. In some embodiments, the solvent has a dielectric constant greater than 20.

Some examples of high boiling aprotic solvents include, but are not limited to, N-methyl-2-pyrrolidone (NMP), dimethylacetamide (DMAc), Dimethylsulfoxide (DMSO), Dimethylformamide (DMF), gamma-butyrolactone, dibutyl carbitol, butyl carbitol acetate, diethylene glycol monoethyl ether acetate, propylene glycol monomethyl ether acetate, and the like, and combinations thereof.

In some embodiments of the liquid composition, the solvent is selected from the group consisting of NMP, DMAc, and DMF.

In some embodiments of the liquid composition, the solvent is NMP.

In some embodiments of the liquid composition, the solvent is DMAc.

In some embodiments of the liquid composition, the solvent is DMF.

In some embodiments of the liquid composition, the solvent is gamma-butyrolactone.

In some embodiments of the liquid composition, the solvent is dibutyl carbitol.

In some embodiments of the liquid composition, the solvent is butyl carbitol acetate.

In some embodiments of the liquid composition, the solvent is diethylene glycol monoethyl ether acetate.

In some embodiments of the liquid composition, the solvent is propylene glycol monoethyl ether acetate.

In some embodiments, more than one of the above-noted high boiling aprotic solvents is used in the liquid composition.

In some embodiments, additional co-solvents are used in the liquid composition.

The polyamic acid solution may optionally further contain any of a number of additives. Such additives may be: antioxidants, heat stabilizers, adhesion promoters, coupling agents (e.g., silanes), inorganic fillers or various reinforcing agents, so long as they do not deleteriously affect the desired polyimide properties.

The polyamic acid solution can be prepared using various available methods with respect to the introduction of the components (i.e., monomers and solvents). Some methods of producing polyamic acid solutions include:

(a) a method in which a diamine component and a dianhydride component are previously mixed together and then the mixture is added to a solvent in portions while stirring.

(b) A process wherein a solvent is added to a stirred mixture of diamine and dianhydride components. (contrary to (a) above)

(c) A process wherein a diamine is separately dissolved in a solvent and then a dianhydride is added thereto in a ratio that allows control of the reaction rate.

(d) A process wherein the dianhydride component is separately dissolved in a solvent and then the amine component is added thereto in a ratio which allows control of the reaction rate.

(e) A process wherein a diamine component and a dianhydride component are separately dissolved in a solvent and then the solutions are mixed in a reactor.

(f) A process wherein a polyamic acid with an excess of amine component and another polyamic acid with an excess of dianhydride component are formed beforehand and then reacted with each other in a reactor, in particular in such a way as to produce a non-random or block copolymer.

(g) A process wherein a specified portion of the amine component and dianhydride component are first reacted and then the remaining diamine component is reacted, or vice versa.

(h) A process wherein the components are added in part or in whole to part or all of the solvent in any order, and further wherein part or all of any of the components may be added as a solution in part or all of the solvent.

(i) A process wherein first one of the dianhydride components is reacted with one of the diamine components to provide a first polyamic acid. Another dianhydride component is then reacted with another amine component to provide a second polyamic acid. These polyamic acids are then combined in any of a variety of ways prior to film formation.

Generally, the polyamic acid solution can be obtained by any of the above-disclosed polyamic acid solution preparation methods.

The polyamic acid solution can then be filtered one or more times to reduce the particle content. Polyimide membranes produced from such filtered solutions may exhibit a reduced number of defects and thereby yield superior performance in the electronic applications disclosed herein. Evaluation of filtration efficiency can be performed by a laser particle counter test, in which a representative sample of the polyamic acid solution is cast onto a5 "silicon wafer. After soft-bake/dry, the particle content of the film is evaluated by any number of laser particle counting techniques on commercially available and art-known instruments.

In some embodiments, the polyamic acid solution is prepared and filtered to produce a particle content of less than 40 particles, as measured by a laser particle counter test.

In some embodiments, the polyamic acid solution is prepared and filtered to yield a particle content of less than 30 particles, as measured by a laser particle counter test.

In some embodiments, the polyamic acid solution is prepared and filtered to yield a particle content of less than 20 particles, as measured by a laser particle counter test.

In some embodiments, the polyamic acid solution is prepared and filtered to produce a particle content of less than 10 particles, as measured by a laser particle counter test.

In some embodiments, the polyamic acid solution is prepared and filtered to yield a particle content of 2 particles to 8 particles, as measured by a laser particle counter test.

In some embodiments, the polyamic acid solution is prepared and filtered to yield a particle content of 4 particles to 6 particles, as measured by a laser particle counter test.

An exemplary preparation of the polyamic acid solution is given in the examples.

The overall polyamic acid composition can be named via symbols commonly used in the art. For example, a polyamic acid having a tetracarboxylic acid component of 100% ODPA and a diamine component of 90 mol% Bis-P and 10 mol% TFMB may be represented as:

ODPA//Bis-P/TFMB 100//90/10。

3. polyimide film

There is provided a polyimide film made from the polyamic acid solution described above.

The polyimide has a repeating unit structure of formula V

Wherein:

R^ais the same or different at each occurrence and represents one or more tetracarboxylic acid component residues; and is

R^bIs the same or different at each occurrence and represents one or more aromatic diamine residues;

wherein 30 to 100 mol% of R^bHaving formula II or formula III

Wherein:

R¹and R²Are the same or different and are selected from the group consisting of F, R_fAnd OR_fA group of (a);

R_fis C_1-3A perfluoroalkyl group; and is

Denotes the attachment point;

wherein R is¹And R²Both adjacent to the attachment point;

and further wherein the polyimide film is prepared according to a process comprising, in order and without repetition:

applying a polyamic acid solution comprising one or more tetracarboxylic acid components and one or more diamine components in a high boiling aprotic solvent to a substrate;

soft baking the coated substrate;

the soft baked coated substrate is treated at a plurality of preselected temperatures at a plurality of preselected time intervals.

For R in formula I^aAnd R^bAll of the above-described embodiments of (A) apply equally to R in formula V^aAnd R^b。

For R in formula II as applicable to formula I¹And R²All of the above-described embodiments of (A) apply equally to R in formulae II and III as applied to formula V¹And R²。

A polyimide film is made by coating the polyamic acid solution described above onto a substrate and then imidizing. This can be achieved by thermal or chemical conversion methods. Any known coating method may be used.

Some fluorinated diamines are known to have low reactivity. In order to form a polyimide film having a sufficient molecular weight using these low-reactivity diamines, a plurality of polymerization steps are used. Typically, a polyamic acid solution is prepared using a low-reactivity diamine, the solution is coated and imidized, and the imidized product is dissolved, recoated and imidized. The additional dissolving, recoating and reimidation steps are repeated several times.

Surprisingly and unexpectedly, it has been found that diamines having a residue of formula II or formula III have better reactivity. Polyimide films have sufficient molecular weight and good mechanical properties using a single polymerization and imidization step. With the polyamic acid solutions described herein, there is no need to form an imidized product, dissolve, recoat, and reimidate multiple times.

In some embodiments of the polyimide membrane, the polyimide polymer has a weight average molecular weight (M) of greater than 100,000 based on gel permeation chromatography and polystyrene standards_W)。

In some embodiments of the polyimide membrane, the polyimide polymer has a weight average molecular weight (M) of greater than 150,000 based on gel permeation chromatography and polystyrene standards_W)。

In some embodiments of the polyimide membrane, the polyimide polymer has a molecular weight (M) greater than 200,000 based on gel permeation chromatography and polystyrene standards_W)。

In some embodiments of the polyimide membrane, the polyimide polymer has a weight average molecular weight (M) of greater than 250,000 based on gel permeation chromatography and polystyrene standards_W)。

In some embodiments of the polyimide membrane, the polyimide polymer has a weight average molecular weight (M) of greater than 300,000 based on gel permeation chromatography and polystyrene standards_W)。

In some embodiments of the polyimide membrane, the polyimide polymer has a weight average molecular weight (M) of 100,000 to 400,000 based on gel permeation chromatography and polystyrene standards_W)。

In some embodiments of the polyimide membrane, the polyimide polymer has a weight average molecular weight (M) of 200,000 to 400,000 based on gel permeation chromatography and polystyrene standards_W)。

In some embodiments of the polyimide film, the polyimide polymer has a composition based on gel permeation chromatography and polystyrene standardsWeight average molecular weight (M) of 250,000 to 350,000_W)。

In some embodiments of the polyimide membrane, the polyimide polymer has a weight average molecular weight (M) of 200,000 to 300,000 based on gel permeation chromatography and polystyrene standards_W)。

In some embodiments of the polyimide film, the Coefficient of Thermal Expansion (CTE) in-plane is less than 45 ppm/deg.c from 50 deg.c to 200 deg.c; in some embodiments, less than 30 ppm/deg.C; in some embodiments, less than 20 ppm/deg.C; in some embodiments, less than 15 ppm/deg.C; in some embodiments, 0 ppm/deg.C to 15 ppm/deg.C; in some embodiments, 0 ppm/deg.C to 10 ppm/deg.C.

In some embodiments of polyimide films, the glass transition temperature (T) is for polyimide films cured at temperatures in excess of 300 deg.C_g) Greater than 250 ℃; in some embodiments, greater than 300 ℃; in some embodiments, greater than 350 ℃.

In some embodiments of polyimide films, the 1% TGA weight loss temperature is greater than 350 ℃; in some embodiments, greater than 400 ℃; in some embodiments, greater than 450 ℃.

In some embodiments of the polyimide film, the tensile modulus is 1.5GPa to 15.0 GPa; in some embodiments, 1.5GPa to 12.0 GPa.

In some embodiments of the polyimide film, the elongation at break is greater than 10%.

In some embodiments of the polyimide film, the optical retardation is less than 500 at 550 nm; in some embodiments, less than 200.

In some embodiments of polyimide films, the birefringence at 633nm is less than 0.15; in some embodiments, less than 0.10; in some embodiments, less than 0.05.

In some embodiments of the polyimide film, the haze is less than 1.0%; in some embodiments, less than 0.5%.

In some embodiments of the polyimide film, b is less than 7.5; in some embodiments, less than 5.0; in some embodiments, less than 3.0. In some embodiments of the polyimide film, the YI is less than 12; in some embodiments, less than 10; in some embodiments, less than 5.

In some embodiments of the polyimide film, the transmittance at 400nm is greater than 40%; in some embodiments, greater than 50%; in some embodiments, greater than 60%.

In some embodiments of the polyimide film, the transmittance at 430nm is greater than 60%; in some embodiments, greater than 70%.

In some embodiments of the polyimide film, the transmittance at 450nm is greater than 70%; in some embodiments, greater than 80%.

In some embodiments of the polyimide film, the transmittance at 550nm is greater than 70%; in some embodiments, greater than 80%.

In some embodiments of the polyimide film, the transmittance at 750nm is greater than 70%; in some embodiments, greater than 80%; in some embodiments, greater than 90%.

Any of the above embodiments of polyimide films may be combined with one or more of the other embodiments, so long as they are not mutually exclusive.

Polyimide films are prepared from polyamic acid solutions by chemical or thermal conversion methods. The polyimide films disclosed herein (particularly when used as flexible substitutes for glass in electronic devices) are prepared by thermal conversion or modified thermal conversion processes and chemical conversion processes.

Chemical conversion processes are described in U.S. patent nos. 5,166,308 and 5,298,331, which are incorporated by reference herein in their entirety. In such processes, a conversion chemical is added to the polyamic acid solution. Conversion chemicals found useful in the present invention include, but are not limited to: (i) one or more dehydrating agents such as aliphatic acid anhydrides (acetic anhydride, etc.) and acid anhydrides; and (ii) one or more catalysts such as aliphatic tertiary amines (triethylamine, etc.), tertiary amines (dimethylaniline, etc.), and heterocyclic tertiary amines (pyridine, picoline, isoquinoline, etc.). The anhydride dehydrating material is typically used in a slight molar excess of the amount of amic acid groups present in the polyamic acid solution. The amount of acetic anhydride used is typically about 2.0 to 3.0 moles per equivalent of polyamic acid. Generally, a substantial amount of tertiary amine catalyst is used.

The thermal conversion process may or may not employ a conversion chemical (i.e., a catalyst) to convert the polyamic acid casting solution to polyimide. If conversion chemicals are used, the process may be considered an improved thermal conversion process. In both types of thermal conversion processes, only thermal energy is used to heat the film to not only dry the solvent film but also perform the imidization reaction. The polyimide membranes disclosed herein are typically prepared using a thermal conversion process with or without a conversion catalyst.

The specific process parameters are pre-selected considering that not only the film composition yields the properties of interest. Conversely, the curing temperature and temperature ramp profile also play an important role in achieving the most desirable characteristics for the intended use disclosed herein. The polyamic acid should be imidized at or above the maximum temperature of any subsequent processing step (e.g., deposition of the inorganic or other layer(s) required to produce a functional display), but at a temperature below the temperature at which significant thermal degradation/discoloration of the polyimide occurs. It should also be noted that inert atmospheres are generally preferred, particularly when higher processing temperatures are employed for imidization.

For the polyamic acids/polyimides disclosed herein, temperatures of 300 ℃ to 320 ℃ are typically employed when subsequent processing temperatures in excess of 300 ℃ are required. Selection of an appropriate curing temperature allows for a fully cured polyimide that achieves an optimal balance of thermal and mechanical properties. Due to this very high temperature, an inert atmosphere is required. Typically, it should adopt<100ppm of furnace oxygen level. Very low oxygen levels enable the use of the highest curing temperatures without significant degradation/discoloration of the polymer. The catalyst that accelerates the imidization process is effective to achieve higher levels of imidization at curing temperatures of about 200 ℃ to 300 ℃. If the flexible device is below the T of the polyimide_gMay optionally be used.

The amount of time for each possible curing step is also an important process consideration. In general, the time for the highest temperature cure should be kept to a minimum. For example, for a 320 ℃ cure, the cure time can be as long as about 1 hour under an inert atmosphere; but at higher curing temperatures this time should be shortened to avoid thermal degradation. Generally, a higher temperature indicates a shorter time. One skilled in the art will recognize the balance between temperature and time in order to optimize the properties of the polyimide for a particular end use.

In some embodiments, the polyamic acid solution is converted to a polyimide film via a thermal conversion process.

In some embodiments of the thermal conversion process, the polyamic acid solution is coated onto the substrate such that the resulting film has a soft-bake thickness of less than 50 μm.

In some embodiments of the thermal conversion process, the polyamic acid solution is coated onto the substrate such that the resulting film has a soft-bake thickness of less than 40 μm.

In some embodiments of the thermal conversion process, the polyamic acid solution is coated onto the substrate such that the resulting film has a soft-bake thickness of less than 30 μm.

In some embodiments of the thermal conversion process, the polyamic acid solution is coated onto the substrate such that the resulting film has a soft-bake thickness of less than 20 μm.

In some embodiments of the thermal conversion process, the polyamic acid solution is coated onto the substrate such that the soft-bake thickness of the resulting film is 10 μm to 20 μm.

In some embodiments of the thermal conversion process, the polyamic acid solution is coated onto the substrate such that the soft-bake thickness of the resulting film is 15 μm to 20 μm.

In some embodiments of the thermal conversion process, the polyamic acid solution is coated onto the substrate such that the soft-bake thickness of the resulting film is 18 μm.

In some embodiments of the thermal conversion process, the polyamic acid solution is coated onto the substrate such that the resulting film has a soft-bake thickness of less than 10 μm.

In some embodiments of the thermal conversion process, the coated substrate is soft baked on a hot plate in a proximity mode, wherein nitrogen is used to hold the coated substrate just above the hot plate.

In some embodiments of the thermal conversion process, the coated substrate is soft baked on a hot plate in full contact mode, wherein the coated substrate is in direct contact with the hot plate surface.

In some embodiments of the thermal conversion process, the coated substrate is soft baked on a hot plate using a combination of a close-in mode and a full-contact mode.

In some embodiments of the thermal conversion process, the coated substrate is soft baked using a hot plate set at 80 ℃.

In some embodiments of the thermal conversion process, the coated substrate is soft baked using a hot plate set at 90 ℃.

In some embodiments of the thermal conversion process, the coated substrate is soft baked using a hot plate set at 100 ℃.

In some embodiments of the thermal conversion process, the coated substrate is soft baked using a hot plate set at 110 ℃.

In some embodiments of the thermal conversion process, the coated substrate is soft baked using a hot plate set at 120 ℃.

In some embodiments of the thermal conversion process, the coated substrate is soft baked using a hot plate set at 130 ℃.

In some embodiments of the thermal conversion process, the coated substrate is soft baked using a hot plate set at 140 ℃.

In some embodiments of the thermal conversion process, the coated substrate is soft baked for a total time of more than 10 minutes.

In some embodiments of the thermal conversion process, the coated substrate is soft baked for a total time of less than 10 minutes.

In some embodiments of the thermal conversion process, the coated substrate is soft baked for a total time of less than 8 minutes.

In some embodiments of the thermal conversion process, the coated substrate is soft baked for a total time of less than 6 minutes.

In some embodiments of the thermal conversion process, the coated substrate is soft baked for a total time of 4 minutes.

In some embodiments of the thermal conversion process, the coated substrate is soft baked for a total time of less than 4 minutes.

In some embodiments of the thermal conversion process, the coated substrate is soft baked for a total time of less than 2 minutes.

In some embodiments of the thermal conversion process, the soft-baked coated substrate is then cured at 2 preselected temperatures for 2 preselected time intervals, wherein the time intervals may be the same or different.

In some embodiments of the thermal conversion process, the soft-baked coated substrate is then cured at 3 preselected temperatures for 3 preselected time intervals, wherein each of these time intervals may be the same or different.

In some embodiments of the thermal conversion process, the soft-baked coated substrate is then cured at 4 preselected temperatures for 4 preselected time intervals, wherein each of these time intervals may be the same or different.

In some embodiments of the thermal conversion process, the soft-baked coated substrate is then cured at 5 preselected temperatures for 5 preselected time intervals, wherein each of these time intervals may be the same or different.

In some embodiments of the thermal conversion process, the soft-baked coated substrate is then cured at 6 preselected temperatures for 6 preselected time intervals, wherein each of these time intervals may be the same or different.

In some embodiments of the thermal conversion process, the soft-baked coated substrate is then cured at 7 preselected temperatures for 7 preselected time intervals, wherein each of these time intervals may be the same or different.

In some embodiments of the thermal conversion process, the soft-baked coated substrate is then cured at 8 preselected temperatures for 8 preselected time intervals, wherein each of these time intervals may be the same or different.

In some embodiments of the thermal conversion process, the soft-baked coated substrate is then cured at 9 preselected temperatures for 9 preselected time intervals, wherein each of these time intervals may be the same or different.

In some embodiments of the thermal conversion process, the soft-baked coated substrate is then cured at 10 preselected temperatures for 10 preselected time intervals, wherein each of these time intervals may be the same or different.

In some embodiments of the thermal conversion process, the preselected temperature is greater than 80 ℃.

In some embodiments of the thermal conversion process, the preselected temperature is equal to 100 ℃.

In some embodiments of the thermal conversion process, the preselected temperature is greater than 100 ℃.

In some embodiments of the thermal conversion process, the preselected temperature is equal to 150 ℃.

In some embodiments of the thermal conversion process, the preselected temperature is greater than 150 ℃.

In some embodiments of the thermal conversion process, the preselected temperature is equal to 200 ℃.

In some embodiments of the thermal conversion process, the preselected temperature is greater than 200 ℃.

In some embodiments of the thermal conversion process, the preselected temperature is equal to 250 ℃.

In some embodiments of the thermal conversion process, the preselected temperature is greater than 250 ℃.

In some embodiments of the thermal conversion process, the preselected temperature is equal to 300 ℃.

In some embodiments of the thermal conversion process, the preselected temperature is greater than 300 ℃.

In some embodiments of the thermal conversion process, the preselected temperature is equal to 350 ℃.

In some embodiments of the thermal conversion process, the preselected temperature is greater than 350 ℃.

In some embodiments of the thermal conversion process, the preselected temperature is equal to 400 ℃.

In some embodiments of the thermal conversion process, the preselected temperature is greater than 400 ℃.

In some embodiments of the thermal conversion process, the preselected temperature is equal to 450 ℃.

In some embodiments of the thermal conversion process, the preselected temperature is greater than 450 ℃.

In some embodiments of the thermal conversion process, one or more of the preselected time intervals is 2 minutes.

In some embodiments of the thermal conversion process, one or more of the preselected time intervals is 5 minutes.

In some embodiments of the thermal conversion process, one or more of the preselected time intervals are 10 minutes.

In some embodiments of the thermal conversion process, one or more of the preselected time intervals are 15 minutes.

In some embodiments of the thermal conversion process, one or more of the preselected time intervals are 20 minutes.

In some embodiments of the thermal conversion process, one or more of the preselected time intervals are 25 minutes.

In some embodiments of the thermal conversion process, one or more of the preselected time intervals is 30 minutes.

In some embodiments of the thermal conversion process, one or more of the preselected time intervals is 35 minutes.

In some embodiments of the thermal conversion process, one or more of the preselected time intervals is 40 minutes.

In some embodiments of the thermal conversion process, one or more of the preselected time intervals are 45 minutes.

In some of the thermal conversion processes, one or more of the preselected time intervals are 50 minutes.

In some embodiments of the thermal conversion process, one or more of the preselected time intervals are 55 minutes.

In some embodiments of the thermal conversion process, one or more of the preselected time intervals is 60 minutes.

In some embodiments of the thermal conversion process, one or more of the preselected time intervals is greater than 60 minutes.

In some embodiments of the thermal conversion process, one or more of the preselected time intervals are from 2 minutes to 60 minutes.

In some embodiments of the thermal conversion process, one or more of the preselected time intervals are from 2 minutes to 90 minutes.

In some embodiments of the thermal conversion process, one or more of the preselected time intervals are from 2 minutes to 120 minutes.

In some embodiments of the thermal conversion process, the process for preparing a polyimide film comprises the following steps in order: applying a polyamic acid solution to a substrate; soft baking the coated substrate; the soft-baked coated substrate is treated at a plurality of preselected temperatures for a plurality of preselected time intervals whereby the polyimide film exhibits properties that are satisfactory for use in electronic applications such as those disclosed herein.

In some embodiments of the thermal conversion process, the process for preparing a polyimide film consists of, in order: applying a polyamic acid solution to a substrate; soft baking the coated substrate; the soft-baked coated substrate is treated at a plurality of preselected temperatures for a plurality of preselected time intervals whereby the polyimide film exhibits properties that are satisfactory for use in electronic applications such as those disclosed herein.

In some embodiments of the thermal conversion process, the process for preparing a polyimide film consists essentially of, in order: applying a polyamic acid solution to a substrate; soft baking the coated substrate; the soft-baked coated substrate is treated at a plurality of preselected temperatures for a plurality of preselected time intervals whereby the polyimide film exhibits properties that are satisfactory for use in electronic applications such as those disclosed herein.

Typically, the polyamic acid solution/polyimide disclosed herein is coated/cured onto a supporting glass substrate to aid in processing during the rest of the display fabrication process. At some point in the process as determined by the display manufacturer, the polyimide coating is removed from the supporting glass substrate by a mechanical or laser lift-off process. These processes separate the polyimide, which is a film with a deposited display layer, from the glass and achieve a flexible form. Typically, this polyimide film with the deposited layer is then bonded to a thicker but still flexible plastic film to provide support for subsequent fabrication of the display.

Improved thermal conversion processes are also provided wherein the conversion catalyst generally allows the imidization reaction to be carried out at lower temperatures than would be possible in the absence of such conversion catalysts.

In some embodiments, the polyamic acid solution is converted to a polyimide film via a modified thermal conversion process.

In some embodiments of the improved thermal conversion process, the polyamic acid solution further comprises a conversion catalyst.

In some embodiments of the improved thermal conversion process, the polyamic acid solution further contains a conversion catalyst selected from the group consisting of tertiary amines.

In some embodiments of the improved thermal conversion process, the polyamic acid solution further comprises a conversion catalyst selected from the group consisting of: tributylamine, dimethylethanolamine, isoquinoline, 1, 2-dimethylimidazole, N-methylimidazole, 2-ethyl-4-imidazole, 3, 5-lutidine, 3, 4-lutidine, 2, 5-lutidine, 5-methylbenzimidazole, and the like.

In some embodiments of the improved thermal conversion process, the conversion catalyst is present at 5 wt% or less of the polyamic acid solution.

In some embodiments of the improved thermal conversion process, the conversion catalyst is present at 3 wt.% or less of the polyamic acid solution.

In some embodiments of the improved thermal conversion process, the conversion catalyst is present at 1 wt% or less of the polyamic acid solution.

In some embodiments of the improved thermal conversion process, the conversion catalyst is present at 1 weight percent of the polyamic acid solution.

In some embodiments of the improved thermal conversion process, the polyamic acid solution further comprises tributylamine as a conversion catalyst.

In some embodiments of the improved thermal conversion process, the polyamic acid solution further contains dimethylethanolamine as a conversion catalyst.

In some embodiments of the improved thermal conversion process, the polyamic acid solution further contains isoquinoline as a conversion catalyst.

In some embodiments of the improved thermal conversion process, the polyamic acid solution further contains 1, 2-dimethylimidazole as a conversion catalyst.

In some embodiments of the improved thermal conversion process, the polyamic acid solution further contains 3, 5-lutidine as a conversion catalyst.

In some embodiments of the improved thermal conversion process, the polyamic acid solution further contains 5-methylbenzimidazole as a conversion catalyst.

In some embodiments of the improved thermal conversion process, the polyamic acid solution further contains N-methylimidazole as a conversion catalyst.

In some embodiments of the improved thermal conversion process, the polyamic acid solution further contains 2-methylimidazole as a conversion catalyst.

In some embodiments of the improved thermal conversion process, the polyamic acid solution further contains 2-ethyl-4-imidazole as a conversion catalyst.

In some embodiments of the improved thermal conversion process, the polyamic acid solution further contains 3, 4-lutidine as a conversion catalyst.

In some embodiments of the improved thermal conversion process, the polyamic acid solution further contains 2, 5-lutidine as a conversion catalyst.

In some embodiments of the improved thermal conversion process, the polyamic acid solution is coated onto the substrate such that the resulting film has a soft-bake thickness of less than 50 μm.

In some embodiments of the improved thermal conversion process, the polyamic acid solution is coated onto the substrate such that the resulting film has a soft-bake thickness of less than 40 μm.

In some embodiments of the improved thermal conversion process, the polyamic acid solution is coated onto the substrate such that the resulting film has a soft-bake thickness of less than 30 μm.

In some embodiments of the improved thermal conversion process, the polyamic acid solution is coated onto the substrate such that the resulting film has a soft-bake thickness of less than 20 μm.

In some embodiments of the improved thermal conversion process, the polyamic acid solution is coated onto the substrate such that the resulting film has a soft-bake thickness of 10 μm to 20 μm.

In some embodiments of the improved thermal conversion process, the polyamic acid solution is coated onto the substrate such that the soft-bake thickness of the resulting film is 15 μm to 20 μm.

In some embodiments of the improved thermal conversion process, the polyamic acid solution is coated onto the substrate such that the soft-bake thickness of the resulting film is 18 μm.

In some embodiments of the improved thermal conversion process, the polyamic acid solution is coated onto the substrate such that the resulting film has a soft-bake thickness of less than 10 μm.

In some embodiments of the improved thermal conversion process, the coated substrate is soft baked on a hot plate in a proximity mode, wherein nitrogen is used to hold the coated substrate just above the hot plate.

In some embodiments of the improved thermal conversion process, the coated substrate is soft baked on a hot plate in full contact mode, wherein the coated substrate is in direct contact with the hot plate surface.

In some embodiments of the improved thermal conversion process, the coated substrate is soft baked on a hot plate using a combination of a close-in mode and a full-contact mode.

In some embodiments of the improved thermal conversion process, the coated substrate is soft baked using a hot plate set at 80 ℃.

In some embodiments of the improved thermal conversion process, the coated substrate is soft baked using a hot plate set at 90 ℃.

In some embodiments of the improved thermal conversion process, the coated substrate is soft baked using a hot plate set at 100 ℃.

In some embodiments of the improved thermal conversion process, the coated substrate is soft baked using a hot plate set at 110 ℃.

In some embodiments of the improved thermal conversion process, the coated substrate is soft baked using a hot plate set at 120 ℃.

In some embodiments of the improved thermal conversion process, the coated substrate is soft baked using a hot plate set at 130 ℃.

In some embodiments of the improved thermal conversion process, the coated substrate is soft baked using a hot plate set at 140 ℃.

In some embodiments of the improved thermal conversion process, the coated substrate is soft-baked for a total time of more than 10 minutes.

In some embodiments of the improved thermal conversion process, the coated substrate is soft-baked for a total time of less than 10 minutes.

In some embodiments of the improved thermal conversion process, the coated substrate is soft baked for a total time of less than 8 minutes.

In some embodiments of the improved thermal conversion process, the coated substrate is soft-baked for a total time of less than 6 minutes.

In some embodiments of the improved thermal conversion process, the coated substrate is soft baked for a total time of 4 minutes.

In some embodiments of the improved thermal conversion process, the coated substrate is soft baked for a total time of less than 4 minutes.

In some embodiments of the improved thermal conversion process, the coated substrate is soft baked for a total time of less than 2 minutes.

In some embodiments of the improved thermal conversion process, the soft-baked coated substrate is then cured at 2 preselected temperatures for 2 preselected time intervals, wherein the time intervals may be the same or different.

In some embodiments of the improved thermal conversion process, the soft-baked coated substrate is then cured at 3 preselected temperatures for 3 preselected time intervals, wherein each of these time intervals may be the same or different.

In some embodiments of the improved thermal conversion process, the soft-baked coated substrate is then cured at 4 preselected temperatures for 4 preselected time intervals, wherein each of these time intervals may be the same or different.

In some embodiments of the improved thermal conversion process, the soft-baked coated substrate is then cured at 5 preselected temperatures for 5 preselected time intervals, wherein each of these time intervals may be the same or different.

In some embodiments of the improved thermal conversion process, the soft-baked coated substrate is then cured at 6 preselected temperatures for 6 preselected time intervals, wherein each of these time intervals may be the same or different.

In some embodiments of the improved thermal conversion process, the soft-baked coated substrate is then cured at 7 preselected temperatures for 7 preselected time intervals, wherein each of these time intervals may be the same or different.

In some embodiments of the improved thermal conversion process, the soft-baked coated substrate is then cured at 8 preselected temperatures for 8 preselected time intervals, wherein each of these time intervals may be the same or different.

In some embodiments of the improved thermal conversion process, the soft-baked coated substrate is then cured at 9 preselected temperatures for 9 preselected time intervals, wherein each of these time intervals may be the same or different.

In some embodiments of the improved thermal conversion process, the soft-baked coated substrate is then cured at 10 preselected temperatures for 10 preselected time intervals, wherein each of these time intervals may be the same or different.

In some embodiments of the improved thermal conversion process, the preselected temperature is greater than 80 ℃.

In some embodiments of the improved thermal conversion process, the preselected temperature is equal to 100 ℃.

In some embodiments of the improved thermal conversion process, the preselected temperature is greater than 100 ℃.

In some embodiments of the improved thermal conversion process, the preselected temperature is equal to 150 ℃.

In some embodiments of the improved thermal conversion process, the preselected temperature is greater than 150 ℃.

In some embodiments of the improved thermal conversion process, the preselected temperature is equal to 200 ℃.

In some embodiments of the improved thermal conversion process, the preselected temperature is greater than 200 ℃.

In some embodiments of the improved thermal conversion process, the preselected temperature is equal to 220 ℃.

In some embodiments of the improved thermal conversion process, the preselected temperature is greater than 220 ℃.

In some embodiments of the improved thermal conversion process, the preselected temperature is equal to 230 ℃.

In some embodiments of the improved thermal conversion process, the preselected temperature is greater than 230 ℃.

In some embodiments of the improved thermal conversion process, the preselected temperature is equal to 240 ℃.

In some embodiments of the improved thermal conversion process, the preselected temperature is greater than 240 ℃.

In some embodiments of the improved thermal conversion process, the preselected temperature is equal to 250 ℃.

In some embodiments of the improved thermal conversion process, the preselected temperature is greater than 250 ℃.

In some embodiments of the improved thermal conversion process, the preselected temperature is equal to 260 ℃.

In some embodiments of the improved thermal conversion process, the preselected temperature is greater than 260 ℃.

In some embodiments of the improved thermal conversion process, the preselected temperature is equal to 270 ℃.

In some embodiments of the improved thermal conversion process, the preselected temperature is greater than 270 ℃.

In some embodiments of the improved thermal conversion process, the preselected temperature is equal to 280 ℃.

In some embodiments of the improved thermal conversion process, the preselected temperature is greater than 280 ℃.

In some embodiments of the improved thermal conversion process, the preselected temperature is equal to 290 ℃.

In some embodiments of the improved thermal conversion process, the preselected temperature is greater than 290 ℃.

In some embodiments of the improved thermal conversion process, the preselected temperature is equal to 300 ℃.

In some embodiments of the improved thermal conversion process, the preselected temperature is less than 300 ℃.

In some embodiments of the improved thermal conversion process, the preselected temperature is less than 290 ℃.

In some embodiments of the improved thermal conversion process, the preselected temperature is less than 280 ℃.

In some embodiments of the improved thermal conversion process, the preselected temperature is less than 270 ℃.

In some embodiments of the improved thermal conversion process, the preselected temperature is less than 260 ℃.

In some embodiments of the improved thermal conversion process, the preselected temperature is less than 250 ℃.

In some embodiments of the improved thermal conversion process, one or more of the preselected time intervals are 2 minutes.

In some embodiments of the improved thermal conversion process, one or more of the preselected time intervals are 5 minutes.

In some embodiments of the improved thermal conversion process, one or more of the preselected time intervals are 10 minutes.

In some embodiments of the improved conversion process, one or more of the preselected time intervals are 15 minutes.

In some embodiments of the improved thermal conversion process, one or more of the preselected time intervals are 20 minutes.

In some embodiments of the improved thermal conversion process, one or more of the preselected time intervals are 25 minutes.

In some embodiments of the improved thermal conversion process, one or more of the preselected time intervals are 30 minutes.

In some embodiments of the improved thermal conversion process, one or more of the preselected time intervals are 35 minutes.

In some embodiments of the improved thermal conversion process, one or more of the preselected time intervals are 40 minutes.

In some embodiments of the improved thermal conversion process, one or more of the preselected time intervals are 45 minutes.

In some embodiments of the improved thermal conversion process, one or more of the preselected time intervals are 50 minutes.

In some embodiments of the improved thermal conversion process, one or more of the preselected time intervals are 55 minutes.

In some embodiments of the improved thermal conversion process, one or more of the preselected time intervals are 60 minutes.

In some embodiments of the improved thermal conversion process, one or more of the preselected time intervals are greater than 60 minutes.

In some embodiments of the improved thermal conversion process, one or more of the preselected time intervals are from 2 minutes to 60 minutes.

In some embodiments of the improved thermal conversion process, one or more of the preselected time intervals are from 2 minutes to 90 minutes.

In some embodiments of the improved thermal conversion process, one or more of the preselected time intervals are from 2 minutes to 120 minutes.

In some embodiments of the improved thermal conversion process, the process for preparing a polyimide film comprises the following steps in order: applying a polyamic acid solution comprising a conversion chemical to a substrate; soft baking the coated substrate; the soft-baked coated substrate is treated at a plurality of preselected temperatures for a plurality of preselected time intervals whereby the polyimide film exhibits properties that are satisfactory for use in electronic applications such as those disclosed herein.

In some embodiments of the improved thermal conversion process, the process for preparing a polyimide film consists of, in order: applying a polyamic acid solution comprising a conversion chemical to a substrate; soft baking the coated substrate; the soft-baked coated substrate is treated at a plurality of preselected temperatures for a plurality of preselected time intervals whereby the polyimide film exhibits properties that are satisfactory for use in electronic applications such as those disclosed herein.

In some embodiments of the improved thermal conversion process, the process for preparing a polyimide film consists essentially of, in order: applying a polyamic acid solution comprising a conversion chemical to a substrate; soft baking the coated substrate; the soft-baked coated substrate is treated at a plurality of preselected temperatures for a plurality of preselected time intervals whereby the polyimide film exhibits properties that are satisfactory for use in electronic applications such as those disclosed herein.

5. Electronic device

The polyimide films disclosed herein can be suitable for use in a variety of layers in electronic display devices, such as OLED and LCD displays. Non-limiting examples of such layers include device substrates, touch panels, substrates for color filters, cover films, and the like. The specific material property requirements for each application are unique and can be addressed by one or more suitable compositions and one or more processing conditions of the polyimide films disclosed herein.

In some embodiments, the flexible substitute for glass in an electronic device is a polyimide film having repeating units of formula IV as described in detail above.

Organic electronic devices that may benefit from having one or more layers that include at least one compound as described herein include, but are not limited to: (1) a device that converts electrical energy to radiation (e.g., a light emitting diode display, a lighting device, a light source, or a diode laser), (2) a device that detects signals by electronic means (e.g., a photodetector, a photoconductive cell, a photoresistor, a photorelay, a phototransistor, a phototube, an IR detector, a biosensor), (3) a device that converts radiation to electrical energy (e.g., a photovoltaic device or a solar cell), (4) a device that converts light of one wavelength to light of a longer wavelength (e.g., a down-conversion phosphor device); and (5) devices that include one or more electronic components that include one or more organic semiconductor layers (e.g., transistors or diodes). Other uses of the composition according to the present invention include coating materials for memory storage devices, antistatic films, biosensors, electrochromic devices, solid electrolyte capacitors, energy storage devices (such as rechargeable batteries), and electromagnetic shielding applications.

One illustration of a polyimide film that can serve as a flexible substitute for glass as described herein is shown in fig. 1. The flexible film 100 may have the characteristics as described in embodiments of the present disclosure. In some embodiments, polyimide films that can serve as flexible substitutes for glass are included in electronic devices. Fig. 2 illustrates the case when the electronic device 200 is an organic electronic device. The device 200 has a substrate 100, an anode layer 110 and a second electrical contact layer, a cathode layer 130, and a photoactive layer 120 therebetween. Additional layers may optionally be present. Adjacent the anode may be a hole injection layer (not shown), sometimes referred to as a buffer layer. Adjacent to the hole injection layer may be a hole transport layer (not shown) comprising a hole transport material. Adjacent the cathode may be an electron transport layer (not shown) comprising an electron transport material. Alternatively, the device may use one or more additional hole injection or hole transport layers (not shown) proximate to anode 110 and/or one or more additional electron injection or electron transport layers (not shown) proximate to cathode 130. The layers between 110 and 130 are individually and collectively referred to as organic active layers. Additional layers that may or may not be present include color filters, touch panels, and/or overlay sheets. One or more of these layers (in addition to the substrate 100) may also be made of the polyimide film disclosed herein.

These various layers will be discussed further herein with reference to fig. 2. However, the discussion is equally applicable to other configurations.

In some embodiments, the different layers have the following thickness ranges: substrate 100, 5-100 microns, anode 110,in some embodiments of the present invention, the,a hole injection layer (not shown),in some embodiments of the present invention, the,a hole-transporting layer (not shown),in some embodiments of the present invention, the,the photoactive layer (120) is disposed on the substrate,in some embodiments of the present invention, the,an electron transport layer (not shown),in some embodiments of the present invention, the, the cathode(s) 130 are provided,in some embodiments of the present invention, the,the ratio of layer thicknesses desired will depend on the exact nature of the materials used.

In some embodiments, an organic electronic device (OLED) contains a flexible substitute for glass as disclosed herein.

In some embodiments, an organic electronic device includes a substrate, an anode, a cathode, and a photoactive layer therebetween, and further includes one or more additional organic active layers. In some embodiments, the additional organic active layer is a hole transport layer. In some embodiments, the additional organic active layer is an electron transport layer. In some embodiments, the additional organic layer is both a hole transport layer and an electron transport layer.

The anode 110 is an electrode that is particularly effective for injecting positive charge carriers. It may be made of, for example, a material containing a metal, mixed metal, alloy, metal oxide or mixed metal oxide, or it may be a conductive polymer, and mixtures thereof. Suitable metals include group 11 metals, metals from groups 4, 5 and 6 and transition metals from groups 8 to 10. If the anode is to be light transmissive, mixed metal oxides of group 12, 13 and 14 metals, such as indium tin oxide, are typically used. The anode may also comprise an organic material such as polyaniline, as described in "Flexible light-emitting diodes made of soluble conductive polymers", Nature, volume 357, page 477479 (11/6/1992). At least one of the anode and cathode should be at least partially transparent to allow the light generated to be observed.

The optional hole injection layer may include a hole injection material. The term "hole injection layer" or "hole injection material" is intended to refer to a conductive or semiconductive material and may have one or more functions in an organic electronic device, including, but not limited to, planarization of underlying layers, charge transport and/or charge injection properties, scavenging of impurities such as oxygen or metal ions, and other aspects that facilitate or improve the performance of the organic electronic device. The hole injection material may be a polymer, oligomer, or small molecule, and may be in the form of a solution, dispersion, suspension, emulsion, colloidal mixture, or other composition.

The hole injection layer may be formed from a polymeric material, such as Polyaniline (PANI) or polyethylene dioxythiophene (PEDOT), which are typically doped with a protic acid. The protonic acid may be, for example, poly (styrenesulfonic acid), poly (2-acrylamido-2-methyl-1-propanesulfonic acid), or the like. The hole injection layer 120 may include a charge transfer compound, etc., such as copper phthalocyanine and tetrathiafulvalene-tetracyanoquinodimethane system (TTF-TCNQ). In some embodiments, the hole injection layer 120 is made from a dispersion of a conductive polymer and a colloid-forming polymeric acid. Such materials have been described, for example, in published U.S. patent applications 2004-0102577, 2004-0127637 and 2005-0205860.

Other layers may include hole transport materials. Examples of hole transport materials for hole transport layers are outlined in, for example, Kirk-Othmer Encyclopedia of Chemical Technology, Kock. Oas Encyclopedia of Chemical engineering, fourth edition, Vol.18, p.837-. Both hole transporting small molecules and polymers can be used. Common hole transport molecules include, but are not limited to: 4,4', 4 "-tris (N, N-diphenyl-amino) -triphenylamine (TDATA); 4,4', 4 "-tris (N-3-methylphenyl-N-phenyl-amino) -triphenylamine (MTDATA); n, N '-diphenyl-N, N' -bis (3-methylphenyl) - [1,1 '-biphenyl ] -4,4' -diamine (TPD); 4,4' -bis (carbazol-9-yl) biphenyl (CBP); 1, 3-bis (carbazol-9-yl) benzene (mCP); 1, 1-bis [ (di-4-tolylamino) phenyl ] cyclohexane (TAPC); n, N ' -bis (4-methylphenyl) -N, N ' -bis (4-ethylphenyl) - [1,1' - (3,3' -dimethyl) biphenyl ] -4,4' -diamine (ETPD); tetrakis- (3-methylphenyl) -N, N' -2, 5-Phenylenediamine (PDA); alpha-phenyl-4-N, N-diphenylaminostyrene (TPS); p- (diethylamino) benzaldehyde Diphenylhydrazone (DEH); triphenylamine (TPA); bis [4- (N, N-diethylamino) -2-methylphenyl ] (4-methylphenyl) methane (MPMP); 1-phenyl-3- [ p- (diethylamino) styryl ] -5- [ p- (diethylamino) phenyl ] pyrazoline (PPR or DEASP); 1, 2-trans-bis (9H-carbazol-9-yl) cyclobutane (DCZB); n, N ' -tetrakis (4-methylphenyl) - (1,1' -biphenyl) -4,4' -diamine (TTB); n, N '-bis (naphthalen-1-yl) -N, N' -bis- (phenyl) benzidine (α -NPB); and porphyrin compounds such as copper phthalocyanine. Common hole transport polymers include, but are not limited to, polyvinylcarbazole, (phenylmethyl) polysilane, poly (dioxythiophene), polyaniline, and polypyrrole. It is also possible to obtain hole-transporting polymers by incorporating hole-transporting molecules such as those described above into polymers such as polystyrene and polycarbonate. In some cases, triarylamine polymers, especially triarylamine-fluorene copolymers, are used. In some cases, the polymers and copolymers are crosslinkable. Examples of crosslinkable hole-transporting polymers can be found, for example, in published U.S. patent application 2005-0184287 and published PCT application WO 2005/052027. In some embodiments, the hole transport layer is doped with a p-type dopant, such as tetrafluorotetracyanoquinodimethane and perylene-3, 4,9, 10-tetracarboxyl-3, 4,9, 10-dianhydride.

Depending on the application of the device, the photoactive layer 120 may be a light-emitting layer activated by an applied voltage (as in a light-emitting diode or light-emitting electrochemical cell), a layer of material that absorbs light and emits light with longer wavelengths (as in a down-converting phosphor device), or a layer of material that responds to radiant energy and generates a signal with or without an applied bias (as in a photodetector or photovoltaic device).

In some embodiments, the photoactive layer comprises a compound comprising an emissive compound that is a photoactive material. In some embodiments, the photoactive layer further comprises a host material. Examples of host materials include, but are not limited toPhenanthrene, triphenylene, phenanthrolineNaphthalene, anthracene, quinoline, isoquinoline, quinoxaline, phenylpyridine, carbazole, indolocarbazole, furan, benzofuran, dibenzofuran, benzodifuran, and metal quinoline salt complexes. In some embodiments, the host material is deuterated.

In some embodiments, the photoactive layer comprises (a) an electroluminescent dopant capable of having an emission maximum of 380 to 750nm, (b) a first host compound, and (c) a second host compound. Suitable second host compounds are described above.

In some embodiments, the photoactive layer includes only (a) an electroluminescent dopant capable of having an emission maximum of 380 to 750nm, (b) a first host compound, and (c) a second host compound, wherein there are no additional materials that would substantially alter the operating principle or distinguishing characteristics of the layer.

In some embodiments, the first host is present at a higher concentration than the second host, based on weight in the photoactive layer.

In some embodiments, the weight ratio of the first host to the second host in the photoactive layer is from 10:1 to 1: 10. In some embodiments, the weight ratio is 6:1 to 1: 6; in some embodiments, 5:1 to 1: 2; in some embodiments, 3:1 to 1: 1.

In some embodiments, the weight ratio of dopant to total host is 1:99 to 20: 80; in some embodiments, 5:95 to 15: 85.

In some embodiments, the photoactive layer comprises (a) a red-emitting dopant, (b) a first host compound, and (c) a second host compound.

In some embodiments, the photoactive layer comprises (a) a green-emitting dopant, (b) a first host compound, and (c) a second host compound.

In some embodiments, the photoactive layer comprises (a) a yellow light-emitting dopant, (b) a first host compound, and (c) a second host compound.

The optional layer may simultaneously serve to facilitate electron transport and also serve as a confinement layer to prevent quenching of the exciton at the layer interface. Preferably, this layer promotes electron mobility and reduces exciton quenching.

In some embodiments, such layers include other electron transport materials. Examples of electron transport materials that may be used in the optional electron transport layer include metal chelated oxinoid (oxinoid) compounds, including metal quinolinate derivatives such as tris (8-hydroxyquinolinato) aluminum (AlQ), bis (2-methyl-8-hydroxyquinolinato) (p-phenylphenolato) aluminum (BAlq), tetrakis- (8-hydroxyquinolinato) hafnium (HfQ), and tetrakis- (8-hydroxyquinolinato) zirconium (ZrQ); and azole compounds such as 2- (4-biphenylyl) -5- (4-tert-butylphenyl) -1,3, 4-oxadiazole (PBD), 3- (4-biphenylyl) -4-phenyl-5- (4-tert-butylphenyl) -1,2, 4-Triazole (TAZ), and 1,3, 5-tris (phenyl-2-benzimidazole) benzene (TPBI); quinoxaline derivatives such as 2, 3-bis (4-fluorophenyl) quinoxaline; phenanthrolines, such as 4, 7-diphenyl-1, 10-phenanthroline (DPA) and 2, 9-dimethyl-4, 7-diphenyl-1, 10-phenanthroline (DDPA); a triazine; a fullerene; and mixtures thereof. In some embodiments, the electron transport material is selected from the group consisting of metal quinoline salts and phenanthroline derivatives. In some embodiments, the electron transport layer further comprises an n-type dopant. N-type dopant materials are well known. n-type dopants include, but are not limited to, group 1 and group 2 metals; group 1 and 2 metal salts, e.g. LiF, CsF and Cs₂CO₃(ii) a Group 1 and group 2 metal organic compounds, such as lithium quinolinate; and molecular n-type dopants, e.g. leuco dyes, metal complexes, e.g. W₂(hpp)₄(wherein hpp ═ 1,3,4,6,7, 8-hexahydro-2H-pyrimido- [1, 2-a)]-pyrimidines) and cobaltocenes, tetrathiatetracenes, bis (ethylenedithio) tetrathiafulvalenes, heterocyclic or divalent radicals, and dimers, oligomers, polymers, dispiro compounds and polycyclics of the heterocyclic or divalent radicals.

An optional electron injection layer may be deposited on the electron transport layer. Examples of electron injecting materials include, but are not limited to, Li-containing organometallic compounds, LiF, Li₂O, lithium quinolinate; organometallic compounds containing Cs, CsF, Cs₂O and Cs₂CO₃. This layer may react with the underlying electron transport layer, the overlying cathode, or both. When an electron injection layer is present, the amount of material deposited is generallyIn some embodiments

The cathode 130 is an electrode that is particularly effective for injecting electrons or negative charge carriers. The cathode may be any metal or nonmetal having a work function lower than that of the anode. The material for the cathode may be selected from group 1 alkali metals (e.g., Li, Cs), group 2 (alkaline earth) metals, group 12 metals, including rare earths and lanthanides, and actinides. Materials such as aluminum, indium, calcium, barium, samarium, and magnesium, and combinations may be used.

It is known to have other layers in organic electronic devices. For example, multiple layers (not shown) may be present between the anode 110 and the hole injection layer (not shown) to control the amount of positive charge injected and/or to provide band gap matching of the layers, or to serve as a protective layer. Layers known in the art, such as copper phthalocyanine, silicon oxynitride, fluorocarbons, silanes, or ultra-thin layers of metals (such as Pt) may be used. Alternatively, some or all of the anode layer 110, the active layer 120, or the cathode layer 130 may be surface treated to increase charge carrier transport efficiency. The choice of material for each component layer is preferably determined by balancing the positive and negative charges in the emitter layer to provide a device with high electroluminescent efficiency.

It should be understood that each functional layer may be comprised of more than one layer.

The device layer may generally be formed by any deposition technique or combination of techniques, including vapor deposition, liquid deposition, and thermal transfer. Substrates such as glass, plastic and metal may be used. Conventional vapor deposition techniques such as thermal evaporation, chemical vapor deposition, and the like may be used. The organic layers may be applied from solutions or dispersions in suitable solvents using conventional coating or printing techniques including, but not limited to, coating, dip coating, roll-to-roll techniques, ink jet printing, continuous nozzle printing, screen printing, gravure printing, and the like.

For liquid phase precipitationBy product methods, one skilled in the art can readily determine suitable solvents for a particular compound or related class of compounds. For some applications, it is desirable that these compounds be dissolved in a non-aqueous solvent. Such non-aqueous solvents may be relatively polar, e.g. C₁To C₂₀Alcohols, ethers and acid esters, or may be relatively non-polar, e.g. C₁To C₁₂Alkane or aromatic compounds such as toluene, xylene, trifluorotoluene, etc. Other suitable liquids for making liquid compositions comprising the novel compounds (as solutions or dispersions as described herein) include, but are not limited to, chlorinated hydrocarbons (e.g., dichloromethane, chloroform, chlorobenzene), aromatic hydrocarbons (e.g., substituted and unsubstituted toluene and xylenes, including trifluorotoluene), polar solvents (e.g., Tetrahydrofuran (THP), N-methylpyrrolidone), esters (e.g., ethyl acetate), alcohols (isopropanol), ketones (cyclopentanone), and mixtures thereof. Suitable solvents for the electroluminescent material have been described, for example, in published PCT application WO 2007/145979.

In some embodiments, the device is made by liquid phase deposition of a hole injection layer, a hole transport layer, and a photoactive layer, and by vapor deposition of an anode, an electron transport layer, an electron injection layer, and a cathode onto a flexible substrate.

It will be appreciated that the efficiency of the device may be increased by optimizing other layers in the device. For example, more efficient cathodes such as Ca, Ba or LiF may be used. Shaped substrates and novel hole transport materials that result in a reduction in operating voltage or increase in quantum efficiency are also applicable. Additional layers may also be added to tailor the energy levels of the various layers and to promote electroluminescence.

In some embodiments, the device has the following structure in order: the light-emitting diode comprises a substrate, an anode, a hole injection layer, a hole transport layer, a light active layer, an electron transport layer, an electron injection layer and a cathode.

Although methods and materials similar or equivalent to those described herein can be used in the practice or testing of the present invention, suitable methods and materials are described below. In addition, the materials, methods, and examples are illustrative only and not intended to be limiting. All publications, patent applications, patents, and other references mentioned herein are incorporated by reference in their entirety.

Examples of the invention

The concepts described herein are further illustrated in the following examples, which do not limit the scope of the invention described in the claims.

Synthesis example 1

This example illustrates the synthesis of 2, 5-difluoro-1, 4-phenylenediamine, compound IV-A.

(a) N- (2, 5-difluorophenyl) -acetamide (1).

In a 1L three-necked flask equipped with a magnetic stir bar, 2, 5-difluoroaniline (152.3g) was dissolved in 500ml of dichloromethane, followed by the addition of acetic anhydride (134.5g), and the mixture was cooled with an ice/water bath, maintaining the internal temperature below 14 ℃ during the addition. The product was filtered, washed with hexane, dried in vacuo. The filtrate was evaporated to a volume of about 200ml, diluted with hexane, and an additional amount of product was collected by filtration. The reaction was carried out three times in succession using a total of 479.4g of 2, 5-difluoroaniline. Combined yield of N- (2, 5-difluorophenyl) -acetamide 1-572.4 g (90.4%).¹H-NMR (acetone-d)₆，500MHz)：2.19(s,3H),6.81-6.86(m,1H),7.16-7.20(m,1H),8.15-8.19(m,1H),9.10(br.s,1H)。

(b) N- (2, 5-difluoro-4-nitrophenyl) -acetamide (2).

To a stirred suspension of N- (2, 5-difluorophenyl) -acetamide 1(235g) in acetic acid (30ml) and concentrated sulfuric acid (350ml) in a 1L three-necked flask was added dropwise a mixture of nitric acid (120ml) and concentrated sulfuric acid (120ml) maintaining the internal temperature below 12 ℃ -13 ℃. After the addition was complete (about 2 hours), the reaction mixture was stirred in a water bath for 3 hours. The reaction mixture was poured into ice and the precipitate was collected by filtration and washed with water. A total of 572.3g of N- (2, 5-difluorophenyl) -acetamide were used for three consecutive reactions. Crude N- (2, 5-difluoro-4-nitrophenyl) -acetylThe combined yield of amine 2, 716.5g, was used in the next step without further purification.¹H-NMR (acetone-d)₆，500MHz)：2.27(s,3H),8.01-8.04(m,1H),8.51-8.55(m,1H),9.74(br.s,1H)。

(c)2, 5-difluoro-4-nitro-aniline (3).

About 358g of crude (2, 5-difluoro-4-nitrophenyl) -acetamide 2 was added portionwise in a 1L three-necked flask containing 450ml of concentrated sulfuric acid, while stirring with a mechanical stirrer. The mixture is heated to 95-100 ℃ within about 45min and maintained at 95-100 ℃ for 10 min. The mixture was cooled with an ice bath, poured into ice and filtered, and the precipitate was washed with water (2 times). The reaction was carried out twice in succession using a total of 716.5g of N- (2, 5-difluorophenyl) -acetamide 2. Combined yield of crude 2, 5-difluoro-4-nitro-aniline 3-477 g (83%).¹H-NMR (acetone-d)₆，500MHz)：6.88(br.s,2H),6.72-6.76(m,1H),7.82-7.86(m,1H)。

(d)2, 5-difluoro-1, 4-phenylenediamine (Compound IV-A).

The starting 2, 5-difluoro-4-nitro-aniline 3(100g) was added in one portion to a solution of tin chloride dihydrate (520g) in methanol (400ml) containing concentrated hydrochloric acid (35 ml). Thereafter, the reaction mixture was heated to about 35 ℃ to 40 ℃ with a heating mantle. The exothermic reaction was allowed to reach steady reflux with occasional application of a cooling ice/water bath. After the exothermic reaction had proceeded for about 20 minutes, the mixture was heated at 59 ℃ for 30 minutes and allowed to stand overnight at ambient temperature. The reaction mixture was filtered and washed with methanol to yield the desired hydrochloride salt of the diamine. The reaction was repeated four times in succession using a total of 418g of 2, 5-difluoro-4-nitro-aniline 3. The combined hydrochloride salts were suspended in 700ml of water and neutralized with 50% aqueous sodium hydroxide solution. The mixture was diluted with 1.5L of water and sodium hydroxide until the initially formed precipitate dissolved. The mixture was extracted with ethyl acetate (4 times). The combined ethyl acetate extracts were passed through a filter filled with silica gel, eluting with ethyl acetate. Ethyl acetate was distilled off to minimum volume using a rotary evaporator and treated with hexane. The precipitated product was collected by filtration and dried in vacuo to yield 167g of product. The reduction step is carried out with 50% aqueous sodium hydroxideThe initial filtrate was hydrolyzed, extracted with ethyl acetate (2 times), ethyl acetate distilled to minimum volume, treated with hexane, the precipitate collected by filtration, dried to yield an additional amount of crude product-94.5 g. Total yield of crude product-254.5 g (74%). The crude product was sublimed in portions in vacuo at 150 ℃ to give 245.5g of 2, 5-difluoro-1, 4-phenylenediamine, compound IV-A. Sublimation can be repeated until the desired product purity is achieved.¹H-NMR (acetone-d)₆，500MHz)：4.41(br.s,4H),6.47(t,2H,J＝10Hz)。

Synthesis example 2

This example illustrates the synthesis of 4, 6-difluoro-1, 3-phenylenediamine, compound IV-E.

4, 6-difluoro-1, 3-phenylenediamine (Compound IV-E).

2, 4-difluoro-5-nitro-aniline (25g) was added in one portion to a stirred solution of tin chloride dihydrate (200g) and concentrated hydrochloric acid (30ml) in methanol (500ml), and the reaction mixture was cooled with an ice bath. Thereafter, the mixture was heated at 70 ℃ for 30 min. The reaction mixture was cooled, quenched with 50% aqueous sodium hydroxide, filtered, and the solid washed with methanol. The residue after evaporation of methanol was extracted with acetone, filtered through a filter packed with silica gel, and eluted with acetone. The residue after evaporation of the acetone was dissolved in a dichloromethane-acetone mixture and passed through a silica gel plug again, eluting with acetone. The acetone was distilled off and the residue was sublimed in vacuo at 180 ℃ in a glove box to give 9.5g of product. The product was sublimed twice more to give 8.1g of purified 4, 6-difluoro-1, 3-phenylenediamine, compound IV-E.¹H-NMR (acetone-d)₆，500MHz)：4.63(br.s,4H),6.15(t,1H,J＝9Hz),6.77(t,1H,J＝11Hz)。

Synthesis example 3

This example illustrates the synthesis of 2, 3-difluoro-1, 4-phenylenediamine, compound IV-C.

(a)2, 3-difluoro-1, 4-benzenedicarboxylic acid (6).

A 1L three-necked round bottom flask was charged with 500ml of 1M LDA in tetrahydrofuran/hexane under nitrogen atmosphere and cooled to about-68 ℃ using a dry ice/acetone bath. Thereafter, a solution of 2, 3-difluorobenzoic acid in 75ml of anhydrous tetrahydrofuran was added dropwise through a syringe while stirring with a mechanical stirrer, keeping the internal temperature below-60 ℃. The resulting suspension was stirred at-78 ℃ for 1.5 hours, then poured in portions into dry ice and allowed to reach ambient temperature within 2 hours. The solvent was distilled off, and the residue was suspended in water and subsequently acidified with concentrated hydrochloric acid. The precipitated product was collected by filtration, washed with water, dried in vacuo to yield 32g of crude product, which was dissolved in acetone (about 500 ml). The acetone was distilled off using a rotary evaporator and the precipitated product was collected by filtration and dried in vacuo to yield about 16g of product. An additional amount of precipitate (2.2g) formed when the acetone was evaporated to a minimum and the residue was diluted with toluene.¹H-NMR (acetone-d)₆，500MHz)：7.83-7.84(m,2H),12.08(br.s,2H)。

(b)3, 4-difluoro-1, 4-phenylenediamine (Compound IV-C).

A mixture of the above crude 2, 3-difluoro-1, 4-phthalic acid (8g), tert-butanol (100ml), toluene (400ml), diphenylphosphoryl azide (27.23g) and triethylamine (100g) was stirred at ambient temperature for 1 hour, then gradually heated from 50 ℃ to 100 ℃ over a period of about 1.7 hours, and heated at 100 ℃ for an additional 3 hours. The reaction was repeated again using 17g of crude 2, 3-difluoro-1, 4-benzenedicarboxylic acid, 57.87g of diphenylphosphoryl azide. The combined reaction mixture was washed with water (2 times), the toluene layer was separated, passed through a short plug of silica gel and celite, and washed with toluene. Toluene was distilled off to a volume of about 200ml using a rotary evaporator and the intermediate BOC protected compound was filtered by filtration (¹H-NMR：dmso-d₆500 MHz: 1.44(s,18H),7.22-7.23(m,2H),9.06(s, 2H). ) And, together with 300ml of toluene and 30ml of concentrated hydrochloric acid, at 90 DEG.CThe heat was applied for 3 days. The toluene layer was separated and the aqueous layer was diluted with 200ml of water. The aqueous layer was extracted with ethyl acetate and the extract was passed through a short plug of silica gel. Ethyl acetate was distilled off using a rotary evaporator to give a crude product (8.14g), which was sublimed in vacuo and then crystallized from an ethyl acetate-cyclohexane mixture to give 6g of purified 3, 4-difluoro-1, 4-phenylenediamine, compound IV-C.¹H-NMR(dmso-d₆，500MHz)：4.46(s,4H),6.27-6.39(m,2H)。¹⁹F-NMR(dmso-d₆，500MHz)：159.9。

Polymer example 1

This example illustrates the use of compound IV-A as a diamine to form polyamic acid.

2, 5-difluoro-1, 4-phenylenediamine (6g), 3',4,4' -biphenyltetracarboxylic dianhydride (12.19g, 0.995 equivalents), and N-methylpyrrolidone (103.4g) were stirred under a nitrogen atmosphere for 2 weeks to give a polymer solution having a viscosity of 3358 cps. GPC: mn is 61889, Mw is 143777, Mp is 139220, Mz is 232140, and PDI is 2.33.

Polymer example 2

This example illustrates the use of compounds IV-E as one of two diamines to form polyamic acids.

The monomers were reacted as above to form a polymer solution, using DMAc as the solvent. The ratio of Bis-P to compound IV-E was 90: 10. GPC: mn 61759; mw is 215,962.

Polymer example 3

This example illustrates the formation of a polyimide film having formula V.

The polyamic acid solution from polymer example 2 was filtered through a microfilter, spin coated onto a clean silicon wafer, soft baked on a hot plate at 90 ℃ and placed in an oven. The oven was purged with nitrogen and heated in stages to a maximum cure temperature of 260 ℃. The wafer was removed from the oven, soaked in water and hand layered to produce a polyimide film sample. The properties of the film are given below:

CTE was measured between 50 ℃ and 250 ℃.

As can be seen from the above examples, the fluorinated diamine compounds having the formulas (II) and (III) are sufficiently reactive at ambient conditions to produce a polymer having a molecular weight greater than 100,000. They can be used to form polyimide films having desirable properties.

It should be noted that not all of the activities described above in the general description or the examples are required, that a portion of a specific activity may not be required, and that one or more other activities may be performed in addition to those described. Further, the order of activities listed are not necessarily the order in which they are performed.

In the foregoing specification, the concepts have been described with reference to specific embodiments. However, one of ordinary skill in the art appreciates that various modifications and changes can be made without departing from the scope of the present invention as set forth in the claims below. Accordingly, the specification and figures are to be regarded in an illustrative rather than a restrictive sense, and all such modifications are intended to be included within the scope of present invention.

Benefits, other advantages, and solutions to problems have been described above with regard to specific embodiments. The benefits, advantages, solutions to problems, and any feature or features that may cause any benefit, advantage, or solution to occur or become more pronounced, however, are not to be construed as critical, required, or essential features of any or all the claims.

It is appreciated that certain features are, for clarity, described herein in the context of separate embodiments, may also be provided in combination in a single embodiment. Conversely, various features that are, for brevity, described in the context of a single embodiment, may also be provided separately or in any subcombination. The use of numerical values in the various ranges specified herein is stated to be approximate as if both the minimum and maximum values in the ranges were preceded by the word "about". In this manner, slight variations above and below the stated ranges can be used to achieve substantially the same results as values within the ranges. Moreover, the disclosure of these ranges is intended as a continuous range including every value between the minimum and maximum average values, including fractional values that may result when some components of one value are mixed with components of a different value. Further, when broader and narrower ranges are disclosed, it is within the contemplation of the invention to match the minimum values from one range with the maximum values from the other range, and vice versa.