阅读说明：本技术 树脂组合物，以及使用该组合物所制得的预浸渍片、金属箔积层板与印刷电路板 (Resin composition, and prepreg, metal foil laminate and printed wiring board produced using the same ) 是由 廖志伟 曾冠勋 林宗贤 黄竹鸣 于 2018-06-19 设计创作，主要内容包括：本发明提供一种树脂组合物,其包含以下成分：(A)环氧树脂；(B)具下式(I)的化合物,<Image he="111" wi="700" file="DDA0001699397830000011.GIF" imgContent="drawing" imgFormat="GIF" orientation="portrait" inline="no"></Image>式(I)中,R<Sub>1</Sub>与R<Sub>2</Sub>各自独立为-H、-CH<Sub>3</Sub>或-C(CH<Sub>3</Sub>)<Sub>3</Sub>；以及(C)视需要的填料。(The invention provides a resin composition, which comprises the following components: (A) an epoxy resin; (B) a compound of the following formula (I), in the formula (I), R 1 And R 2 Each independently is-H, -CH 3 or-C (CH) 3 ) 3 (ii) a And (C) optionally a filler.)

1. A resin composition, comprising:

(A) an epoxy resin;

(B) a compound of the following formula (I),

in the formula (I), R₁And R₂Each independently is-H, -CH₃or-C (CH)₃)₃(ii) a And

(C) optionally a filler.

2. The resin composition of claim 1, wherein R is₁And R₂Are all-H.

3. The resin composition according to claim 1, wherein the optional filler (C) is selected from the group consisting of: silica, alumina, magnesia, magnesium hydroxide, calcium carbonate, talc, clay, aluminum nitride, boron nitride, aluminum hydroxide, aluminum silicon carbide, sodium carbonate, titanium dioxide, zinc oxide, zirconia, quartz, diamond-like diamond, graphite, calcined kaolin, mica, hydrotalcite, Polytetrafluoroethylene (PTFE) powder, glass beads, ceramic whiskers, carbon nanotubes, nanoscale inorganic powders, and combinations of the foregoing.

4. The resin composition of claim 1, further comprising a crosslinker selected from the group consisting of: maleimide-based compounds, anhydrides, and combinations thereof.

5. The resin composition according to claim 4, wherein the maleimide-based compound is a compound of the following formula (II),

in the formula (II), R₃Is methylene (-CH)₂-), 4' -diphenylmethyleneMeta-phenylene radicalBisphenol A Diphenyl Ether group3,3' -dimethyl-5, 5' -diethyl-4, 4' -diphenylmethyl alkyl4-methyl-1, 3-phenyleneOr (2,2, 4-trimethyl) -1, 6-hexylene

6. The resin composition of claim 5, wherein R is₃Is 3,3' -dimethyl-5, 5' -diethyl-4, 4' -diphenylmethyl alkyl

7. The resin composition of claim 4, wherein the anhydride is a copolymer of styrene and maleic anhydride (SMA copolymer).

8. The resin composition according to claim 7, wherein the copolymer of styrene and maleic anhydride has a ratio of repeating units derived from styrene to repeating units derived from maleic anhydride of 3 to 8 in a molecule.

9. The resin composition according to claim 8, wherein the copolymer of styrene and maleic anhydride has a ratio of repeating units derived from styrene to repeating units derived from maleic anhydride of 3.5 to 4.5 in a molecule.

10. The resin composition according to any one of claims 1 to 9, wherein the compound (B) of formula (I) is contained in an amount of 6 to 40% by weight based on the solid content of the resin composition excluding the optional filler (C).

11. The resin composition according to any one of claims 1 to 9, further comprising a co-crosslinking agent (co-crosslinking agent) selected from the group consisting of: cyanate ester resins (cyanate ester), compounds containing-OH groups, compounds containing amine groups, reactive ester compounds, and combinations of the foregoing.

12. The resin composition according to any one of claims 1 to 9, further comprising a flame retardant.

13. The resin composition according to any one of claims 1 to 9, further comprising a hardening accelerator.

14. The resin composition according to any one of claims 1 to 9, further comprising at least one of a dispersant and a coupling agent.

15. A prepreg obtained by impregnating or coating a substrate with the resin composition according to any one of claims 1 to 14 and drying the impregnated or coated substrate.

16. A metal foil laminate produced by laminating the prepreg according to claim 15 with a metal foil, or by applying the resin composition according to any one of claims 1 to 14 to a metal foil and drying the applied metal foil.

17. A printed circuit board produced from the metal foil laminate as set forth in claim 16.

Technical Field

The present invention relates to a resin composition, and more particularly to an epoxy resin-based resin composition which can provide an electronic material having the following advantages: low dielectric constant (Dk), low dielectric dissipation factor (Df), low water absorption, good heat resistance, and good finished appearance. The resin composition of the present invention can be used as a composite material or a prepreg with glass fiber, or can be further used as an adhesive for metal foil to prepare a laminate, a printed circuit board and a carrier for Integrated Circuit (IC) carrier.

Background

With the increasing demand for data transmission capacity in the field of electronic communication technology, the application of electronic products is developing in higher frequency region, and the demand for dielectric properties (Dk and Df) of related electronic materials is increasing. In addition, the process temperature of the printed circuit board is becoming higher due to the development of the lead-free process, and thus the heat resistance requirement of the dielectric layer material of the metal foil laminate for the production of the printed circuit board is becoming more severe. In addition, the circuit density of the printed circuit board is continuously increased, so that the diameter of the micro holes for interlayer connection of the multilayer circuit board is smaller and the pitch (pitch) between the micro holes is narrower (for example, only 0.8 mm, 0.65 mm), which makes the high temperature reliability of the printed circuit board more strictly required.

Epoxy resin is a thermosetting resin that has long been used in electronic materials. Epoxy resins and phenolic resins (phenolic novolac resin) have been used in resin compositions in the early days, so as to improve the heat resistance of the resin compositions after curing. However, byproducts are generated during the curing reaction of the epoxy resin and the phenolic resin, which results in poor physicochemical properties of the resin composition after curing. To solve this technical problem, studies have been made to replace the phenolic resin with benzoxazine resin (also referred to herein as "BZ resin") as a hardener. BZ resins are increasingly widely used in epoxy resin-based resin compositions because the hardening mechanism of BZ resins is a ring-opening-polymerization reaction that generates little volatile by-product.

The use of BZ resins has been described as early as taiwan patent publication No. 460537, which discloses a BZ compound formed by reacting a phenol, monoamine (monoamine) compound and formaldehyde, which can be used in combination with an epoxy resin or a phenolic resin as a hardener. In addition to this, common commercially available BZ hardeners also include: bisphenol A type BZ (also referred to herein as "BPA-BZ"), such as the product available from Hensman (Hunstman) under the type LZ-8290; bisphenol F type BZ (also referred to herein as "BPF-BZ"), such as the product available from Hensmei corporation as model LZ-8280; and phenolphthalein type BZ, such as model LZ-8270 available from Hensman. However, the electronic materials prepared by using the above BZ hardener still have a problem of insufficient heat resistance.

In order to further improve the problem of heat resistance, studies have been made to obtain a BZ curing agent having further improved heat resistance by substituting a diamine (di-amine) compound having two amine groups for a monoamine compound in the synthesis reaction of the BZ compound. For example, chinese patent publication No. CN 103210009B discloses an ODA-type BZ hardener formed by reacting phenol, 4,4'-diaminodiphenyl ether (4,4' -oxydianiline, also known as 4,4'-oxydianiline, 4,4' -ODA)) and formaldehyde, and the electronic material prepared by using the ODA-type BZ hardener has good heat resistance and excellent flame retardancy. Commercially available BZ hardeners of the ODA type are for example products from the vinblastic resin with the model number PF-3500And model JBZ-OP100N from Jeffy chemical (JFE Chemicals)

Further, taiwan patent publication No. I610982 discloses a formulation of an epoxy resin composition, in which the same ODA type BZ curing agent as described in chinese patent No. CN 103210009B is used, and a copolymer of styrene and maleic anhydride (SMA copolymer) and a tetra-functional phenol compound (tetra-functional phenol compound) are further used, and it is desired to further improve the heat resistance of the obtained electronic material.

Disclosure of Invention

It has been found that, compared with an electronic material prepared by using a resin composition containing a BPA-BZ hardener, the electronic material prepared by using a resin composition containing an ODA-type BZ hardener can be improved in glass transition temperature (Tg), but the electronic material still has a problem of poor dielectric properties (Dk and Df), and particularly, when it is applied to a high-frequency electronic product, the dielectric loss factor (Df) is easily too high. In addition, it has been found that electronic materials produced using resin compositions containing ODA-type BZ hardeners also have a problem of appearance defects (e.g., fish eyes), resulting in poor yield.

In view of the above technical problems, the present invention provides a resin composition, which can be used for preparing electronic materials having the advantages of good heat resistance, good dielectric properties (low Dk and low Df), good appearance of finished products, and the like. As described in the following objects, the technical means of the present invention to solve the problems lies in using benzoxazine resin with specific structure in epoxy resin composition, so that the electronic material prepared from the resin composition can have the advantages mentioned above, especially, improved dielectric properties and finished product appearance.

An object of the present invention is to provide a resin composition comprising the following components:

(A) an epoxy resin;

(B) a compound of the following formula (I),

in the formula (I), R₁And R₂Each independently is-H, -CH₃or-C (CH)₃)₃(ii) a And (C) optionally a filler.

In some embodiments of the invention, in formula (I), R₁And R₂Are all-H.

In some embodiments of the invention, the optional filler (C) is selected from the group consisting of: silica, alumina, magnesia, magnesium hydroxide, calcium carbonate, talc, clay, aluminum nitride, boron nitride, aluminum hydroxide, aluminum silicon carbide, sodium carbonate, titanium dioxide, zinc oxide, zirconia, quartz, diamond-like diamond, graphite, calcined kaolin, mica, hydrotalcite, Polytetrafluoroethylene (PTFE) powder, glass beads, ceramic whiskers, carbon nanotubes, nanoscale inorganic powders, and combinations of the foregoing.

In some embodiments of the invention, the resin composition further comprises a crosslinker selected from the group consisting of: maleimide-based compounds, anhydrides, and combinations thereof.

In some embodiments of the invention, the maleimide-based compound is a compound of the following formula (II),

in the formula (II), R₃Is methylene (-CH)₂-), 4' -diphenylmethyleneMeta-phenylene radicalBisphenol A Diphenyl Ether group3,3' -dimethyl-5, 5' -diethyl-4, 4' -diphenylmethyl alkyl4-methyl-1, 3-phenyleneOr (2,2, 4-trimethyl) -1, 6-hexyleneAnd is preferably 3,3' -dimethyl-5, 5' -diethyl-4, 4' -diphenylmethyl-alkyl

In some embodiments of the invention, the anhydride is a copolymer of styrene and maleic anhydride, and the ratio of repeat units derived from styrene to repeat units derived from maleic anhydride in the molecule of the copolymer of styrene and maleic anhydride can be 3 to 8, specifically 3.5 to 4.5, more specifically 4.

In some embodiments of the invention, the compound (B) of formula (I) is present in an amount of from 6 to 40% by weight, based on the solids content of the resin composition excluding optional filler (C).

In some embodiments of the invention, the resin composition further comprises a co-crosslinking agent (co-crosslinking agent) selected from the group consisting of: cyanate ester resins (cyanate ester), compounds containing-OH groups, compounds containing amine groups, reactive ester compounds, and combinations of the foregoing.

In some embodiments of the present invention, the resin composition further comprises at least one of a flame retardant and a hardening accelerator.

In some embodiments of the present invention, the resin composition further comprises at least one of a dispersant and a coupling agent.

Another object of the present invention is to provide a prepreg obtained by impregnating or coating a substrate with the resin composition described above and drying the impregnated or coated substrate.

It is still another object of the present invention to provide a metal foil laminate obtained by laminating the prepreg and the metal foil as described above, or obtained by applying the resin composition as described above to a metal foil and drying the applied metal foil.

It is another object of the present invention to provide a printed circuit board, which is made of the metal foil laminate as described above.

In order to make the aforementioned objects, features and advantages of the present invention comprehensible, some embodiments accompanied with figures are described in detail below.

Detailed Description

Some specific embodiments according to the present invention will be specifically described below; however, the invention may be embodied in many different forms without departing from the spirit thereof, and the scope of the invention should not be limited to the specific embodiments described.

As used in this specification (and particularly in the claims), the terms "a," "an," "the," and the like are to be understood to encompass both the singular and the plural, unless the context clearly dictates otherwise.

Unless otherwise indicated herein, the ingredients contained in a solution, mixture or composition are described in this specification in terms of solids (dry weight), i.e., the weight of the solvent not included.

Compared with the prior art, the resin composition has the advantages that benzoxazine resin with a specific structure is used, the dielectric property of the electronic material prepared from the resin composition can be improved, and the benzoxazine structure at the tail end of the molecular structure can endow the prepared electronic material with good heat resistance. In addition, the benzoxazine resin with specific structure has good compatibility with epoxy resin and the existing cross-linking agent such as bismaleimide resin or SMA resin, so that the prepared electronic material has good finished product appearance. The components and preparation of the resin composition of the present invention will now be described in detail.

1. Resin composition

The resin composition of the present invention comprises an epoxy resin (A), an essential component such as a compound (B) represented by the formula (I), and optionally a filler (C) and optionally another component (D). The details of each component are as follows.

1.1. Epoxy resin (A)

Herein, the epoxy resin means a thermosetting resin having at least two epoxy functional groups in one molecule, and includes, but is not limited to, a bifunctional epoxy resin, a tetrafunctional epoxy resin, an octafunctional epoxy resin, or a novolac epoxy resin. In the resin composition of the present invention, the kind of the epoxy resin is not particularly limited, and those skilled in the art can select the epoxy resin as needed after the present specification. For example, a bromine-containing epoxy resin may be used for the flame retardant property of the resin composition, or a bromine-free epoxy resin may be used in response to the environmental requirement of no halogen.

Epoxy resins that can be used in the present invention include bisphenol type epoxy resins, novolac type epoxy resins, stilbene type epoxy resins, triazine (triazine) skeleton-containing epoxy resins, triphenol methane type epoxy resins, phenylene (xylene) type epoxy resins, biphenyl aralkyl type epoxy resins, naphthalene type epoxy resins, fluorene skeleton-containing epoxy resins, dicyclopentadiene (DCPD) type epoxy resins, and alicyclic epoxy resins. The bisphenol epoxy resin is, for example, bisphenol a epoxy resin, bisphenol F epoxy resin, or bisphenol S epoxy resin. The novolac type epoxy resin is, for example, a phenol novolac type epoxy resin, a cresol novolac type epoxy resin, a bisphenol a novolac type epoxy resin, or a bisphenol F novolac type epoxy resin.

Specific examples of epoxy resins useful in the present invention include, but are not limited to, 1, 4-butanediol diglycidyl ether, 1, 6-hexanediol diglycidyl ether, (poly) ethylene glycol diglycidyl ether, (poly) propylene glycol diglycidyl ether, trimethylolethane triglycidyl ether, trimethylolpropane triglycidyl ether, 1, 4-cyclohexanedimethanol diglycidyl ether, 1, 2-epoxy-4- (epoxyethyl) cyclohexane, glycerol triglycidyl ether, diglycerol polyglycidyl ether, 2, 6-diglycidylphenylglycidyl ether, 1, 3-tris (4-glycidoxyphenyl) propane, 1, 2-cyclohexanedicarboxylic acid diglycidyl ester, 4' -methylenebisglycidyl etherBis (N, N-diglycidylaniline), 3, 4-epoxycyclohexanecarboxylic acid-3 ',4' -epoxycyclohexylmethyl ester, triglycidyl-p-aminophenol, tetraglycidyl-m-xylylenediamine, tetraglycidyl-diaminodiphenylmethane, tetraglycidyl-1, 3-diaminomethylcyclohexane, bisphenol A diglycidyl ether, bisphenol S diglycidyl ether, tetrabromobisphenol A diglycidyl ether, hydrogenated bisphenol A diglycidyl ether, neopentylglycol tetraglycidyl ether, neopentylglycol polyglycidyl ether, resorcinol diglycidyl ether, phthalic acid diglycidyl ester, tetrahydrophthalic acid diglycidyl ester, neopentyl glycol diglycidyl ether, bisphenol hexafluoroacetone diglycidyl ether, isocyanuric acid triglycidyl ester, Tris (3, 4-epoxybutyl) isocyanurate, tris (4, 5-epoxypentyl) isocyanurate, tris (5, 6-epoxyhexyl) isocyanurate, tris (7, 8-epoxyoctyl) isocyanurate, tris (2-glycidoxyethyl) isocyanurate, monoallyl isocyanurate, N ' -diglycidyl-N "- (2, 3-dipropyloxypropyl) isocyanurate, N ' -bis (2, 3-dipropyloxypropyl) -N" -glycidyl isocyanurate, tris (2,2-bis (glycidyloxymethyl) butyl) -3,3',3 "- (2,4, 6-triphenoxy-1, 3, 5-triazine-1, 3, 5-triyl) tripropionate, sorbitol polyglycidyl ether, adipic acid diglycidyl ester, dibromophenyl glycidyl ether, 1,2,7, 8-diepoxyoctane, 1, 6-dimethylolperfluorohexane diglycidyl ether, 4- (spiro [3, 4-epoxycyclohexane-1, 5' - [1,3 ]]IIAlkane (I) and its preparation method]-2 '-yl) -1, 2-epoxycyclohexane, 1, 2-bis (3, 4-epoxycyclohexylmethoxy) ethane, 4, 5-epoxy-2-methylcyclohexanecarboxylic acid 4',5 '-epoxy-2' -methylcyclohexylmethyl ester, ethylene glycol bis (3, 4-epoxycyclohexanecarboxylate), bis (3, 4-epoxycyclohexylmethyl) adipate, and bis (2, 3-epoxycyclopentyl) ether. Examples of the epoxy resin may also include diglycidyl ether compounds of polyfunctional phenols and polycyclic aromatic compounds such as anthracene. Further, a phosphorus compound may be introduced into the epoxy resin to form a phosphorus-containing epoxy resin, and examples thereof may be exemplified by 9,10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (9,10-dihydro-9-oxa-10-phosphahenanthrene-10-oxide, DOPO) -modified epoxy resin.

The epoxy resins can be used individually or in combination, and can be self-prepared by one of ordinary skill in the art according to actual needs. In some embodiments of the invention, it is preferred to use an epoxy resin having a high glass transition temperature. In the examples that follow, a novolac type epoxy resin was used.

In the resin composition of the present invention, the content of the epoxy resin (a) may be 5 to 30% by weight, more specifically 8 to 25% by weight, for example, 9,10, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 21, 22, 23, or 24% by weight, based on the solid content of the resin composition excluding the optional filler (C). Within the above specified range, the epoxy resin can fully exert its advantages without affecting the properties of other components of the resin composition, for example, can provide electronic materials with good metal foil adhesion and insulation properties.

1.2. A compound (B) represented by the formula (I)

The resin composition of the present invention comprises a compound represented by the following formula (I):

in the formula (I), R₁And R₂Each independently is-H, -CH₃or-C (CH)₃)₃. In some embodiments of the invention, R₁And R₂Are all-H.

The compound represented by the formula (I) is a benzoxazine resin, which can be prepared by a general benzoxazine resin preparation method, as described in detail below.

Benzoxazine resins are known to be produced from phenolic hydroxyl compounds, monoamine compounds and formaldehyde according to the following reaction scheme (a):

in reaction formula (a), examples of the phenolic hydroxyl compound include, but are not limited to, phenol, 4-methylphenol, tert-butylphenol, and the like. Monoamine compound (R)₄-NH₂) R of (A) to (B)₄Can be alkyl, cycloalkyl, phenyl, or phenyl substituted with alkyl or alkoxy groups, such as methylamine, aniline, and the like. Formaldehyde (HCHO) may then be provided as formalin or paraformaldehyde.

The compound represented by the formula (I) can be obtained by reacting the monoamine compound (R) in the formula (a)₄-NH₂) By diamines, e.g. 2,2' -bis [4- (4-aminophenoxyphenyl)]Propane (structural formula:) And 4-methylphenol is used as the phenolic hydroxyl compound, and the preparation method is not the technical focus of the present invention, and the ordinary skilled person in the art can easily complete the preparation method based on the description of the present specification and the common knowledge thereof, or refer to the related preparation method described in chinese patent No. CN 103210009B, and no further description is given herein. The chinese patent No. CN 103210009B is incorporated herein by reference in its entirety.

In the resin composition of the present invention, the compound represented by formula (I) can effectively reduce the dielectric constant (Dk) and dielectric loss factor (Df) of the electronic material without affecting the heat resistance of the electronic material, and can also prevent the appearance of the finished electronic material from generating fisheye defects. Therefore, the resin composition is particularly suitable for preparing electronic materials in the fields of high frequency and high speed transmission.

In the resin composition of the present invention, the content of the compound (B) represented by the formula (I) may be 3 to 50% by weight, preferably 6 to 40% by weight, for example, 7,8, 9,10, 12, 15, 17, 18, 19, 20, 22, 23, 25, 27, 29, 30, 31, 32, 33, 35, 36, 38, or 39% by weight, based on the solid content of the resin composition excluding the optional filler (C). In the case where the content of the compound (B) represented by the formula (I) is in the aforementioned preferred range, an electronic material having a lower dielectric dissipation factor (Df) and better heat resistance can be obtained. Further, in some preferred embodiments of the present invention, the content of the compound (B) represented by the formula (I) is 18 to 32% by weight, within which an electronic material having excellent heat resistance for drilling can be obtained.

1.3. Optional fillers (C)

The resin composition of the present invention may optionally contain a filler. Suitable fillers include, but are not limited to, organic or inorganic fillers selected from the group consisting of: silica (e.g., hollow silica), alumina, magnesia, magnesium hydroxide, calcium carbonate, talc, clay, aluminum nitride, boron nitride, aluminum hydroxide, aluminum silicon carbide, sodium carbonate, titanium dioxide, zinc oxide, zirconium oxide, quartz, diamond-like, graphite, calcined kaolin, kaolin clay, mica, hydrotalcite, PTFE powder, glass beads, ceramic whiskers, carbon nanotubes, nano-sized inorganic powders, and combinations thereof.

In the resin composition of the present invention, the shape of the filler is not particularly limited, and may be, for example, spherical, fibrous, plate-like, granular, sheet-like, whisker-like, but the present invention is not limited thereto. In addition, the size of the filler is not particularly limited, and is exemplified by spherical or granular fillers having an average particle diameter of generally less than 10 μm, preferably between 0.1 μm and 5. mu.m.

In addition, to increase the compatibility between the filler and other components of the resin composition, the filler may be surface modified with a coupling agent prior to addition to the resin composition. Examples of coupling agents include, but are not limited to, silane-based coupling agents, titanate-based coupling agents, and low-polymerization-degree polysiloxane coupling agents.

The content of the filler in the resin composition of the present invention may be 0 wt% to 40 wt%, for example, 2 wt%, 4 wt%, 6 wt%, 8 wt%, 10 wt%, 12 wt%, 14 wt%, 16 wt%, 18 wt%, 20 wt%, 22 wt%, 24 wt%, 25 wt%, 26 wt%, 27 wt%, 28 wt%, 30 wt%, 32 wt%, 34 wt%, 36 wt%, or 38 wt%, based on the total solid content of the resin composition, but the present invention is not limited thereto, and can be adjusted by one of ordinary skill in the art according to actual needs.

1.4. Other optional ingredients (D)

The resin composition of the present invention may further comprise other optional components such as a crosslinking agent, a co-crosslinking agent, a flame retardant, a hardening accelerator, and additives known in the art, which are described below, to suitably improve the processability of the resin composition during the manufacturing process, or to improve the physicochemical properties of electronic materials made from the resin composition. Additives known in the art include, but are not limited to, dispersants, coupling agents, and toughening agents.

1.4.1. Crosslinking agent

Herein, the crosslinking agent refers to a component that can react with the epoxy resin to undergo crosslinking and curing. The kind of the crosslinking agent is not particularly limited as long as it can react with the epoxy resin. In the resin composition of the present invention, examples of the crosslinking agent include, but are not limited to, maleimide compounds, acid anhydrides, and combinations thereof. Without being limited by theory, the compound of formula (I) has good compatibility with both the maleimide-based compound and the acid anhydride, and thus the compound of formula (I) is suitable for use in an epoxy resin-based resin composition together with the maleimide-based compound and the acid anhydride. The scheme of the cross-linking agent will be further explained below.

1.4.1.1. Maleimides

As used herein, maleimide refers to compounds or oligomers having at least one maleimide functional group. The maleimide functional group has a reactive carbon-carbon double bond, can react with other unsaturated functional groups in the resin composition to generate a crosslinking curing effect, and can improve the heat resistance of a material obtained after the resin composition is cured. Examples of the maleimide include the following bismaleimides having two maleimide functional groups and polyfunctional maleimides having three or more maleimide functional groups.

1.4.1.1.1. Bismaleimide

Specifically, the bismaleimide having two maleimide functional groups may be a compound having the following formula (II):

in the formula (II), R₃Is methylene (-CH)₂-), 4' -diphenylmethyleneMeta-phenylene radicalBisphenol A Diphenyl Ether group3,3' -dimethyl-5, 5' -diethyl-4, 4' -diphenylmethyl alkyl4-methyl-1, 3-phenyleneOr (2,2, 4-trimethyl) -1, 6-hexyleneIn some embodiments of the invention, R₃Is 3,3' -dimethyl-5, 5' -diethyl-4, 4' -diphenylmethyl alkyl

Specific examples of compounds of formula (II) include, but are not limited to, 1, 2-bismaleimidoethane, 1, 6-bismaleimidohexane, 1, 3-bismaleimidobenzene, 1, 4-bismaleimidobenzene, 2, 4-bismaleimidotoluene, 4' -bismaleimidotolueneImidodiphenylmethane, 4' -bismaleimidodiphenyl ether, 3' -bismaleimidodiphenyl sulfone, 4' -bismaleimidodicyclohexylmethane, 3, 5-bis (4-maleimidophenyl) pyridine, 2, 6-bismaleimidopyridine, 1, 3-bis (maleimidomethyl) cyclohexane, 1, 3-bis (maleimidomethyl) benzene, 1-bis (4-maleimidophenyl) cyclohexane, 1, 3-bis (dichloromaleimido) benzene, 4' -biscitraconimidodiphenylmethane (4,4' -biscitraconiodiphenylethanemethane), 2-bis (4-maleimidophenyl) propane, 1-phenyl-1, 1-bis (4-maleimidophenyl) ethane, α -bis (4-maleimidophenyl) toluene, 3, 5-bismaleimide-1, 2, 4-triazole, N '-ethylene-bismaleimide, N' -hexamethylene-bismaleimide, N '-m-phenylene bismaleimide, N' -p-phenylene bismaleimide, N '-4,4' -diphenylmethane bismaleimide, N '-4,4' -diphenyl ether bismaleimide, N '-4,4' -diphenylsulfone bismaleimide, N '-4,4' -dicyclohexylmethane bismaleimide, N, N ' - α, α ' -4,4' -dimethylenecyclohexane bismaleimide, N ' -m-xylylenebismaleimide, N ' -4,4' -diphenylcyclohexanedibismaleimide, and N, N ' -methylenebis (3-chloro-p-phenylene) bismaleimide. Commercially available bismaleimide resins include those available from KI Chemical company under the models BMI-70 and BMI-80, and those available from the Dainization industry under the models BMI-1000, BMI-4000, BMI-5000, BMI-5100, and BMI-7000. The bismaleimides mentioned above can be used alone or in combination, and can be self-formulated by one skilled in the art according to actual needs. In the examples that follow, BMI-5100 (R) was used₃Is 3,3' -dimethyl-5, 5' -diethyl-4, 4' -diphenylmethyl alkyl)。

In the resin composition of the present invention, the maleimide may be contained in an amount of 5 to 35% by weight, more specifically 10 to 30% by weight, for example, 12, 13, 14, 15, 16, 17, 18, 19, 20, 22, 25, or 27% by weight, based on the solid content of the resin composition excluding the optional filler (C).

1.4.1.1.2. Multifunctional maleimide (poly-valent maleinimide)

As used herein, polyfunctional maleimide refers to an oligomer having at least three maleimide functional groups. In some embodiments of the present invention, the polyfunctional maleimide may have the following structure of formula (III):

in formula (III), q is an integer of 1 to 10.

The polyfunctional maleimide can be obtained by condensation reaction of aniline (aniline), formaldehyde and maleic anhydride, and thus, it can also be a mixture of oligomers having different numbers of maleimide functional groups. For a description of the polyfunctional maleimide having the structure of formula (III), reference is made to U.S. Pat. No. 4,4,435,560, which is incorporated herein by reference in its entirety. Commercially available polyfunctional maleimides include those available from the Daihu chemical industry under the type BMI-2000 and BMI-2300(CAS number 67784-74-1).

In the resin composition of the present invention, the content of the polyfunctional maleimide may be 5 to 35% by weight, and particularly 10 to 30% by weight, for example, 11, 12, 13, 14, 15, 16, 17, 18, 19, 20, 22, 25, 27, or 29% by weight, based on the solid content of the resin composition excluding the optional filler (C).

1.4.1.2. Acid anhydrides

Anhydrides refer to organic compounds having two acyl groups bound to the same oxygen atom, typically formed by dehydrating an organic acid. Specific examples of anhydrides include, but are not limited to, mono-anhydrides, acid dianhydrides, polyanhydrides, and copolymers of the foregoing anhydrides with other copolymerizable monomers. Examples of the monoanhydride include, but are not limited to, acetic anhydride, maleic anhydride, or succinic anhydride. Examples of acid dianhydrides include, but are not limited to, naphthalene tetracarboxylic dianhydride (naphthalene tetracarboxylic dianhydride) or pyromelic dianhydride (pyromelitic dianhydride). Examples of polyanhydrides include, but are not limited to, mellitic anhydride (mellitic trianhydride). Examples of copolymers of anhydrides with other copolymerizable monomers include, but are not limited to, copolymers of styrene monomers with maleic anhydride (SMA copolymers).

SMA copolymers are copolymers formed by copolymerizing styrene monomers with maleic anhydride. Without being limited by theory, SMA copolymers in epoxy resin based compositions provide the effect of reducing Dk and Df of the resulting electronic materials. The functional group of maleic anhydride can sufficiently react with the functional group of the epoxy resin, and thus the glass transition temperature (Tg) of the resulting electronic material can be improved.

In general, the SMA copolymer may have the structure of formula (IV):

in formula (IV), m is an integer of 1 to 10, and n is an integer of 8 to 12.

When the resin composition contains the SMA copolymer represented by formula (IV), the higher the ratio of the repeating unit derived from styrene to the repeating unit derived from maleic anhydride in the molecule of the SMA copolymer (i.e., the larger the value of m), the lower the Df value (i.e., the better the dielectric properties) of the electronic material obtained from the resin composition, but the lower the Tg because the content of the repeating unit derived from maleic anhydride is too low. For example, when m is 1, the Tg of the resulting electronic material is 155 ℃, and when m is 8, the Tg of the resulting electronic material is only 104 ℃. Furthermore, when the ratio of the repeating units derived from styrene to the repeating units derived from maleic anhydride is too high (e.g., m ≧ 8), the surface of the prepreg produced will have a large tackiness (tack), which results in easy adhesion between the prepregs to each other and is disadvantageous for subsequent processing operations. Conversely, the lower the content of repeating units derived from styrene in the molecule of the SMA copolymer (i.e., the smaller the m value, e.g., ≦ 3), the higher the Tg of the resulting electronic material and the better the heat resistance, but the more brittle the texture, and the more likely the generation of dust contamination at the subsequent processing. In view of this, when the resin composition of the present invention comprises the SMA copolymer represented by formula (IV), the ratio of the repeating unit derived from styrene to the repeating unit derived from maleic anhydride in the molecule of the SMA copolymer is preferably between 3 and 8, for example, products available from CRAYVALLEY company under the models SMA EF-80 (where m is 8), SMA EF-60 (where m is 6), SMA EF-40 (where m is 4), SMA EF-30 (where m is 3), and SMA-3000 (where m is 3). In the examples that follow, SMA EF-40 was used.

In the resin composition of the present invention, the content of the SMA copolymer may be 10 to 50% by weight, more specifically 20 to 40% by weight, for example, 22, 24, 25, 27, 28, 30, 32, 33, 34, 35, 37, 38, or 39% by weight, based on the solid content of the resin composition excluding the optional filler (C).

The crosslinking agent includes bismaleimide, acid anhydride, and the like, and may be used alone or in combination. In the resin composition of the present invention, the content of the crosslinking agent may be 15 to 85% by weight, more specifically 30 to 60% by weight, for example, 32, 35, 36, 37, 39, 40, 41, 42, 45, 47, 49, 50, 52, 54, 55, 56, 57, or 59% by weight, based on the solid content of the resin composition excluding the optional filler (C).

1.4.2. Co-crosslinking agent

In addition to the above-mentioned crosslinking agents, the resin composition of the present invention may further comprise a co-crosslinking agent to further improve the properties of the electronic material. The co-crosslinking agent may include cyanate ester resin, amine group-containing compound, reactive ester compound, — OH group-containing compound, etc., and each of the co-crosslinking agents may be used alone or in any combination. The scheme of the co-crosslinking agent will be further explained below.

1.4.2.1. Cyanate ester resin

Herein, the cyanate ester resin refers to a chemical substance mainly composed of bisphenol or phenol aldehyde derivative in which a hydrogen atom of at least one hydroxyl group of the bisphenol or phenol aldehyde derivative is substituted with a cyano group (cyano). Cyanate ester resins typically have-OCN groups and can form trimers by crosslinking reactions. Specific examples of the cyanate ester resin include, but are not limited to, 4' -ethylidenebisphenylene cyanate (4,4' -ethylidenebisphenylene cyanate), 4' -dicyanobenzene, 2-bis (4-cyanooxyphenyl) propane, bis (4-cyanooxy-3, 5-dimethylphenyl) methane, bis (4-cyanooxyphenyl) sulfide, bis (4-cyanooxyphenyl) ether, a prepolymer of bisphenol a dicyanate in methyl ethyl ketone, 1-bis (4-cyanooxyphenyl) ethane, 1-bis (4-cyanooxyphenyl) methane, 1, 3-bis (4-cyanooxyphenyl-1- (methylethylene)) benzene, bis (4-cyanooxyphenyl) ether, bis (4-cyanooxyphenyl) -2, 2-butane, 1, 3-bis [2- (4-cyanooxyphenyl) propyl ] benzene, ginseng (4-cyanooxyphenyl) ethane, cyanated phenol aldehyde, and cyanated phenol dicyclopentadiene adduct. The cyanate ester resins mentioned above may be used alone or in any combination thereof. Commercially available cyanate ester resins include products available from the company Longsha (LONZA) under the designations PRIMASET PT-15, PRIMASETPT-30S, PRIMASET PT-60S, PRIMASET CT-90, BADCY, BA-100-10T, BA-200, BA-230S, BA-300S, BTP-2500, BTP-6020S, DT-4000, DT-7000, METHYLCY, and ME-240S.

1.4.2.2. Compounds containing amine groups

Specific examples of the amine group-containing compound include, but are not limited to, Dicyanodiamide (DICY), diaminodiphenyl sulfone (DDS), diaminodiphenyl methane (DDM), Amino Triazine Novolac (ATN) resin, and guanamine (guanamine). Guanamines include 6-substituted guanamines (6-substitated guanamines), such as benzoguanamine (benzoguanamine), acetoguanamine (aceto-guanamine), and decanoylguanamine (caprino-guanamine).

1.4.2.3. Active ester compound

Herein, the active ester compound may be an aromatic polyester polymer (aromatic polyester) obtained by polymerizing an aromatic dicarboxylic acid (or a derivative thereof) with a bisphenol compound (or a derivative thereof). The polymerization reaction can be carried out by a conventional polymerization method such as solution polymerization, interfacial polymerization, melt polymerization, etc. Examples of aromatic dicarboxylic acids include, but are not limited to, terephthalic acid, isophthalic acid, phthalic acid, chlorophthalic acid, nitrophthalic acid, 2, 5-naphthalenedicarboxylic acid, 2, 6-naphthalenedicarboxylic acid, 2, 7-naphthalenedicarboxylic acid, 1, 5-naphthalenedicarboxylic acid, methylphthalic acid, 4 '-biphenyldicarboxylic acid, 2' -biphenyldicarboxylic acid, 4 '-diphenyletherdicarboxylic acid, 4' -diphenylmethanedicarboxylic acid, 4 '-diphenylsulfonedicarboxylic acid, 4' -diphenylisopropylidenedicarboxylic acid, 1, 2-bis (4-carboxyphenoxy) ethane, and sodium 5-sulfoisophthalic acid. The aromatic dicarboxylic acids may be used alone or in any combination thereof. Among the above aromatic dicarboxylic acids, terephthalic acid, isophthalic acid, or a mixture thereof is preferably used, and a mixture of terephthalic acid and isophthalic acid is more preferably used. Examples of bisphenol compounds include, but are not limited to, bis (4-hydroxyphenyl) phenylmethane, 1-bis (4-hydroxyphenyl) -1-phenylethane (1,1-bis (4-hydroxyphenyl) -1-phenylethane) (bisphenol AP, BPAP), 1-bis (4-hydroxy-3-methylphenyl) -1-phenylethane, 1-bis (4-hydroxy-3,5-dimethylphenyl) -1-phenylethane, 1-bis (4-hydroxy-3,5-dibromophenyl) -1-phenylethane, 1-bis (4-hydroxy-3-phenylphenyl) -1-phenylethane, 2-bis (4-hydroxyphenyl) propane (2,2-bis (4-hydroxyphenyl) propane) (bisphenol A, BPA), 2-bis (4-hydroxy-3,5-dimethylphenyl) propane (2,2-bis (4-hydroxy-3,5-dimethylphenyl) propane) (tetramethylbisphenol A), 2-bis (4-hydroxy-3-methylphenyl) propane (2,2-bis (4-hydroxy-3-methylphenyl) propane) (bisphenol C, BPC), 2-bis (4-hydroxy-3,5-dibromophenyl) propane (2,2-bis (4-hydroxy-3,5-dibromophenyl) propane) (tetrabromobisphenol A), and 2,2-bis (4-hydroxy-3,5-dichlorophenyl) propane (4-hydroxy-3,5-dichlorophenyl) propane) (tetrachlorobisphenol A), dicyclopentadiene-phenol (dicyclopentadiene-phenol) polymer. The aforementioned bisphenol compounds may be used alone or in any combination. Among the above bisphenol compounds, BPA, tetramethylbisphenol A, BPC, tetrabromobisphenol A, or tetrachlorobisphenol A is preferably used. Commercially available bisphenol compounds include those available from DIC of Japan under the model number HPC-8000-65T, or from Unitika of Japan under the model number V575.

1.4.2.4. Compounds containing-OH groups

Specific examples of the-OH group-containing compound include, but are not limited to: bisphenol compounds such as bisphenol a, tetrabromobisphenol a, bisphenol S, or bisphenol F; dicyclopentadiene (DCPD) -phenolic copolymers; and a phenolic resin.

The co-crosslinking agent includes cyanate ester resin, amino group-containing compound, active ester compound, and-OH group-containing compound, and may be used alone or in combination. In the resin composition of the present invention, the content of the co-crosslinking agent may be 2 to 30% by weight, more specifically 5 to 20% by weight, based on the solid content of the resin composition excluding the optional filler.

1.4.3. Flame retardant

The resin composition can be further added with a flame retardant, including a halogen-containing flame retardant and a halogen-free flame retardant, so as to improve the flame retardancy of the prepared electronic material. When the resin composition of the present invention has halogen-free requirement, it is preferable to use halogen-free flame retardant.

Examples of halogen-free flame retardants include, but are not limited to, nitrogen-containing compounds, phosphorus-containing compounds, and metal hypophosphites. Examples of nitrogen-containing compounds include, but are not limited to, melamine and its derivatives (e.g., Melapur 200, a product of the BASF corporation). Examples of phosphorus-containing compounds include, but are not limited to, 9, 10-dihydro-9-oxa-10-phosphaphenanthrene-10-oxide (DOPO) and derivatives thereof (e.g., XZ-92741 available from Dow Chemical, Inc., and XP-7866 available from Yabao, Inc.), phenoxycyclophosphazene (e.g., SPB-100, SPH-100, SPV-100 available from Datsukamur Chemical), and resorcinol bis [ di (2, 6-dimethylphenyl) phosphate ] (e.g., PX-200, PX-201, PX-202 available from Daxiba Chemical, Inc.). Examples of metal phosphinates include, but are not limited to, aluminum hypophosphite (e.g., product model OP-935 from Clariant).

The flame retardants mentioned above may be used alone or in any combination thereof. In the resin composition of the present invention, the solid content of the flame retardant is 2 to 20% by weight, more specifically 5 to 15% by weight, based on the solid content of the resin composition. When the content of the flame retardant is less than the specified range (e.g., less than 2% by weight), there is a fear that the desired improvement in flame retardancy cannot be provided, and when the content of the flame retardant is more than the specified range (e.g., more than 20% by weight), there is a fear that properties of the electronic material produced will be adversely affected, for example, dielectric properties of the electronic material become poor, moisture absorption becomes high, tear strength is lowered, and the like.

1.4.4. Hardening accelerator

The resin composition of the present invention may further include a hardening accelerator to accelerate the reaction of the epoxy functional group and to lower the curing reaction temperature of the resin composition. The kind of the hardening accelerator is not particularly limited as long as it promotes the ring-opening of the epoxy functional group and lowers the curing reaction temperature. Suitable hardening accelerators include, but are not limited to, tertiary amines, quaternary ammonium, imidazoles, and pyridines, and each hardening accelerator may be used alone or in combination. Examples of tertiary amines include, but are not limited to, dimethylbenzylamine, 2- (dimethylaminomethyl) phenol, and 2,4, 6-tris (dimethylaminomethyl) phenol. Examples of imidazoles include, but are not limited to, 2-methylimidazole, 2-ethyl-4-methylimidazole (2-ethyl-4-methylimidazole, 2E4MZ), and 2-phenylimidazole. Examples of pyridines include, but are not limited to, 2, 3-diaminopyridine, 2, 5-diaminopyridine, 2, 6-diaminopyridine, 4-dimethylaminopyridine, 2-amino-3-methylpyridine, 2-amino-4-methylpyridine, or 2-amino-3-nitropyridine. Furthermore, hardening accelerators also include transition metals and their oxides, such as zinc or zinc oxide. In the examples which follow, imidazoles and transition metals are used.

The hardening accelerators mentioned above may be used alone or in combination. In general, the content of the hardening accelerator may be 0 wt% to 5 wt%, for example, 0.01 wt%, 0.03 wt%, 0.05 wt%, 0.07 wt%, 0.1 wt%, 0.2 wt%, 0.3 wt%, 0.5 wt%, 0.7 wt%, 1 wt%, or 3 wt%, based on the solid content of the resin composition excluding the optional filler, but the present invention is not limited thereto, and may be adjusted by those skilled in the art according to actual needs.

1.5. Preparation of resin composition

As for the preparation of the resin composition of the present invention, the components of the resin composition, including the epoxy resin, the compound represented by the formula (I), and, if necessary, the filler and other optional components, can be uniformly mixed with a stirrer and dissolved or dispersed in a solvent to be made into a varnish-like form for subsequent processing. The solvent may be any inert solvent that can dissolve or disperse the ingredients of the resin composition, but does not react with the ingredients. By way of example, solvents that may be used to dissolve or disperse the components of the resin composition include, but are not limited to: toluene, γ -butyrolactone, methyl ethyl ketone, cyclohexanone, butanone, acetone, xylene, methyl isobutyl ketone, N-Dimethylformamide (DMF), N-dimethylacetamide (DMAc), and N-methylpyrrolidone (NMP). The solvents can be used individually or in admixture. The amount of the solvent to be used is not particularly limited as long as it can uniformly dissolve or disperse the components of the resin composition therein in principle. In the examples that follow, a mixture of toluene, methyl ethyl ketone, and γ -butyrolactone was used as the solvent.

2. Prepreg

The present invention also provides a prepreg obtained from the above resin composition, wherein the prepreg is obtained by impregnating or coating a substrate with the above resin composition and drying the impregnated or coated substrate. Commonly used substrates include fiberglass reinforcements (fiberglass fabrics, glassine paper, glass mats, etc.), kraft paper, short-staple cotton paper, natural fiber cloth, organic fiber cloth, and the like. In some embodiments of the present invention, a 2116-reinforced glass fiber cloth was used as a reinforcing material (substrate) and heat-dried at 175 ℃ for 2 to 15 minutes (B-stage), thereby producing a prepreg in a semi-cured state.

3. Metal foil laminate and printed wiring board

The present invention also provides a metal foil laminate made of the above prepreg, which comprises a composite layer and a metal layer and can be obtained by laminating the above prepreg with a metal foil or by applying the above resin composition to a metal foil followed by drying the applied metal foil, wherein the composite layer is provided by the above prepreg. In the case of producing a metal foil laminate using prepregs, a plurality of layers of the above prepregs may be stacked, a metal foil (e.g., copper foil) may be stacked on at least one outer side surface of a composite layer composed of the stacked prepregs to provide a stack, and the stack may be subjected to a hot-pressing operation to obtain the metal foil laminate.

The metal foil laminate sheet can be formed into a printed circuit board by further patterning the metal foil on the outer side thereof.