阅读说明：本技术 单取代及多取代官能团芳香酮类化合物、其制备方法及其光聚合引发剂 (Monosubstituted and polysubstituted functional group aromatic ketone compound, preparation method thereof and photopolymerization initiator thereof ) 是由 梁建军 刘国龙 侯占峰 于 2021-10-13 设计创作，主要内容包括：本发明属于辐射固化新材料领域,涉及一种芳香酮类化合物,特别涉及一类单取代或多取代的多官能团芳香酮类化合物、其制备方法,以及以该类化合物为有效成分的含烯键不饱和化合物体系的光聚合组合物。本发明提供了一种单取代及多取代的多官能团芳香酮类化合物,该多官能团芳香酮类化合物具有如(I)所示的通式结构。本发明还包括该多官能团芳香酮类化合物的制备方法和应用。本发明特别关注利用价廉易得的工业级原材料作为起点突破口制备单取代或多取代官能团化芳香酮类化合物,并将该化合物应用于辐射固化中的光引发剂用途,致力于解决光引发剂本身毒性和VOCs污染问题的同时力求其经济竞争力,以降低整体成本并提高光引发效率。(The invention belongs to the field of novel radiation curing materials, and relates to an aromatic ketone compound, in particular to a mono-substituted or multi-substituted multifunctional group aromatic ketone compound, a preparation method thereof, and a photopolymerization composition containing an ethylenic unsaturated compound system with the compound as an effective component. The invention provides a mono-substituted and multi-substituted multifunctional group aromatic ketone compound, which has a general structure shown as (I). The invention also comprises a preparation method and application of the multifunctional aromatic ketone compound. The invention particularly focuses on the preparation of mono-substituted or multi-substituted functional aromatic ketone compounds by using cheap and easily available industrial raw materials as starting points and breaking through, applies the compounds to the application of photoinitiators in radiation curing, and aims at solving the problems of toxicity and VOCs pollution of the photoinitiators and simultaneously striving for economic competitiveness so as to reduce the overall cost and improve the photoinitiation efficiency.)

1. The mono-substituted and multi-substituted multifunctional group aromatic ketone compound is characterized in that the multifunctional group aromatic ketone compound has a general formula structure shown as (I):

wherein the content of the first and second substances,

n is an integer between 1 and 5,

R₁is a group containing one or more substituents,

R₂and R₃The groups are independent of each other, branched or straight-chain alkyl groups having 1 to 12 carbon atoms.

2. The mono-and poly-substituted multifunctional aromatic ketone compound according to claim 1,

R₁is a halogen atom F, Cl, Br, I, -NCO, N-alkyl, -CN, -NO₂Radical, -SO₃H sulfonic acid group, S-alkyl, Si-alkyl, -hydroxymethyl, alkyl, alkenyl, alkynyl or aromatic ring group;

R₂and R₃The groups are independent of each other, and are C1-12 branched or straight-chain alkyl groups containing or not containing a ring system structure; or R₂And R₃The radicals are substituted or interrupted by 1 to 4 oxygen, nitrogen, silicon or sulfur atoms; or R₂And R₃The groups form a cyclic structure.

3. The mono-and poly-substituted multifunctional aromatic ketone compound according to claim 1,

the structure of the multifunctional aromatic ketone compound is selected from, but not limited to, the following structures:

4. the method for preparing mono-or poly-substituted multifunctional aromatic ketone compound according to any one of claims 1 to 3, wherein the mono-or poly-substituted group of the benzene ring is modified to obtain the aromatic ketone compound with multi-modified benzene ring represented by the general formula (I).

5. The process according to claim 4, wherein the mono-or polysubstituted modification of the benzene ring is carried out by a modification before Friedel-crafts acylation of the aromatic ring or after Friedel-crafts acylation of the aromatic ring, depending on the nature of the substituent of the aromatic ring.

6. The process according to claim 5, wherein when the aromatic ring substituent is an electron-donating group, the modification is optionally followed by Friedel-crafts acylation.

7. A hybrid system curable by actinic radiation, characterized in that it comprises at least one polymerizable ethylenically unsaturated compound and a novel aromatic ketone photoinitiator system of the general formula (I) according to any one of claims 1 to 3.

8. The hybrid system according to claim 7, wherein the photoinitiator of the aromatic ketone type defined by formula (I) is used in an amount varying from 0.01 to 20 parts per 100 parts by weight of the total amount of the ethylenically unsaturated substances.

9. The hybrid system according to claim 8, wherein the aromatic ketone photoinitiator defined by the general formula (I) is used in an amount of 0.5 to 10 parts.

10. A photocuring radiation material formula system is characterized in that: the photocuring radiation material formula system has at least one of the following characteristics:

(1) containing at least one photoinitiator as defined by the general formula (I) or mixtures thereof;

(2) containing at least one photoinitiator as defined by the general formula (I) or in a mixture with other customary commercial photoinitiators;

(3) contains at least one ethylenically unsaturated compound.

(4) Additives or/and coagents are included, including but not limited to polymerization inhibitors, leveling agents, defoamers, anti-sagging agents, thickeners, adhesion promoters, dispersants, solubilizers, diluents, antistatic agents, water or organic solvents, antibacterial agents, flame retardants, reactive amine co-initiators, inorganic or organic fillers and/or organic, inorganic colorants, uv absorbers or/and light stabilizers to enhance the weatherability of the coating ink, and suitable aqueous dispersions or water-soluble products of the above components.

11. The photocurable radiation material formulation system of claim 10, wherein:

the ethylenically unsaturated compound is a monomer or a resin.

12. Use of the photocurable radiation material formulation system according to claim 10, characterized in that:

the novel UV radiation curing material formula system is in wooden furniture, plastic product, printing package, and the inkjet is printed, and the electronic consumer goods, motor vehicle interior and exterior trim, pipeline section bar, industry terrace, building curtain, 3D print the application in vibration material disk preparation and boats and ships or container body.

13. The use of claim 12, wherein: the photocurable radiation material formulation systems are used as coatings or inks for the preparation of pigmented and unpigmented paints and varnishes, powder coatings, printing inks, printing plates, adhesives, pressure-sensitive adhesives, dental compositions, gel coats, photoresists for electronics, electrographic resists, etch resists, both liquid and dry films, solder resists, resists for the manufacture of color filters for various display applications, resists for the manufacture of structures in the production process of plasma display panels, electroluminescent displays and LCDs, for LCDs, holographic data storage, compositions for encapsulating electronic components, for the preparation of magnetic recording materials, micromechanical parts, waveguides, optical switches, stencils, etch masks, color proofing systems, glass fiber cable coatings, screen printing stencils, for the production of three-dimensional objects by means of stereolithography, as image recording materials, a decolorizing material for holographic recording, microelectronic circuits, decolorizing materials, for image recording materials using microcapsules, as photoresist material for UV and visible laser direct imaging systems, as photoresist material for forming dielectric layers in sequential build-up layers of printed circuit boards;

alternatively, the first and second electrodes may be,

pigmented and unpigmented paints and varnishes, powder coatings, printing inks, printing plates, adhesives, seals, dental compositions, foams, moulding compounds, composite compositions, glass fibre cable coatings, screen-printing stencils are prepared using the above-described photocurable radiation material formulation systems for producing three-dimensional objects by means of stereolithography as image-recording materials, photoresist compositions, decolorizing materials for image-recording materials, image-recording materials using microcapsules.

Technical Field

The invention belongs to the field of novel radiation curing materials, and relates to an aromatic ketone compound. In particular to mono-substituted or multi-substituted multifunctional aromatic ketone compounds, a preparation method thereof and a photopolymerization initiator of an ethylenically unsaturated compound system taking the compounds as effective components.

Background

In Ultraviolet (UV) radiation curing materials, some hydroxy ketones, bisaryl ketones, and macromolecular hydroxy ketones are known to be useful as radical photopolymerization initiators for ethylenically unsaturated compound-containing systems, and Darocur 1173, Irgacure184, Irgacure 907, and bisaryl ketones BP, etc., listed below, are commercially successful representatives.

However, these photoinitiators generally produce a series of Volatile Organic Compounds (VOCs) which are not friendly to the environment and even seriously harmful to human health, such as benzaldehyde, acetone, cyclohexanone, thioether and the like. Thus, the resulting environmental and health contamination has become an increasing concern in the field of radiation curing. There have been considerable studies and reports on new compounds aimed at solving these problems, among which representative compounds: irgacure 2959, Irgacure127, KIP150, etc.

These studies and structures reflect that a strong development in the field of radiation curing is the need for new environmentally friendly and green, healthy, non-toxic products, and in particular to address the mitigation and elimination of the above-mentioned disadvantages of conventional commercially available photoinitiators in polymerization applications, including cracking or residue resulting in carcinogenicity, reproductive toxicity compounds benzene/thioether/aromatic contamination, release of VOCs, and unpleasant odor remaining after packaging of the finished product. However, from the viewpoint of civil environmental protection, the development of new photoinitiators is not only aimed at solving the above-mentioned challenging problems and providing new green and environmental-friendly compounds, but also at providing new compounds having characteristics of economic cost competitiveness and comprehensive performance competitiveness as much as possible. For example: the KIP150 product overcomes the difficulty of VOCs, and has the new problems of greatly reduced photopolymerization activity (the photopolymerization activity is only 1/4 of Darocure 1173) and greatly increased cost.

Disclosure of Invention

The invention aims to solve the technical problem of providing a novel mono-substituted and multi-substituted functionalized aromatic ketone compound.

The invention also provides a preparation method of the aromatic ketone compound.

The invention also aims to provide application of the aromatic ketone compound, in particular to a free radical photopolymerization initiator of an ethylenic unsaturated compound system taking the aromatic ketone compound as an effective component.

The invention provides a mono-substituted and multi-substituted multifunctional group aromatic ketone compound, which has a general formula structure shown as (I):

wherein the content of the first and second substances,

n is an integer between 1 and 5, for example 1, 2, 3, 4 or 5.

R₁Is a group as one or more substituents, e.g. halogen atom, alkyl group, sulfonic group, nitro groupAromatic groups, and the like.

R₂And R₃The groups are independent of each other, a branched or straight chain with 1-12 carbon atoms, or an alkyl group with or without a ring system structure, R₂And R₃The radicals may also form a cyclic structure, R₂And R₃The groups may be substituted or interrupted by 1 to 4 oxygen, nitrogen, silicon or sulfur atoms. Preferably, R is₁Selected from the group consisting of halogen atoms F, Cl, Br, I, -NCO groups, N-alkyl groups, -CN groups, -NO₂Radical, -SO₃H sulfonic group, S-alkyl, Si-alkyl, alkenyl, alkynyl or aromatic ring group.

Preferably, R is₂And R₃The group is substituted or interrupted by 1 to 4 oxygen, nitrogen, silicon or sulfur atoms.

Preferably, R is₂And R₃The groups may form a cyclic structure.

Preferably, the structure of the polyfunctional aromatic ketone compound is selected from, but not limited to, the following structures:

on the other hand, the invention also provides a preparation method of the mono-substituted and multi-substituted multi-functional group aromatic ketone compound, which is used for modifying the mono-substituted or multi-substituted group of the benzene ring to obtain the aromatic ketone compound with multi-modified benzene ring in the general formula (I).

According to the invention, the mono-substituted or multi-substituted group modification of the benzene ring can be achieved by two ways of performing Friedel-crafts acylation reaction on the aromatic ring before modification or performing Friedel-crafts acylation reaction on the aromatic ring after modification respectively according to the comprehensive consideration of chemical synthesis feasibility and cost economy.

For example, in a preferred embodiment of the present invention, under the protection of nitrogen, anhydrous chlorobenzene is added into a reaction kettle, stirring is started and temperature is reduced, aluminum trichloride is added into the reaction kettle, stirring and temperature reduction are kept for 1 hour, and then cyclohexanecarbonyl chloride is added into the reaction kettle dropwise and slowly added at low temperature. After the completion of the dropwise addition, stirring was continued for 6 hours to obtain a Friedel-crafts acylated intermediate. Then, the primary and secondary chlorinated kettles are alternately arranged in series in two stages, firstly, the primary and secondary chlorinated kettles are respectively filled with Friedel-crafts acylation intermediates, chlorine is introduced into the primary kettle, the chlorine is absorbed by the primary kettle, tail gas containing the chlorine is introduced into the secondary kettle for environment-friendly absorption again, after the chlorine is introduced, chlorine introduction is stopped, nitrogen is introduced into the primary kettle for 20 minutes to replace excessive chlorine, then the chlorinated intermediates of the primary kettle are collected, meanwhile, the Friedel-crafts acylation intermediates are added into the primary kettle again, and the primary kettle is changed into the secondary kettle to repeat the operation. And (3) putting the chlorinated intermediate into a hydrolysis kettle, adding a sodium hydroxide solution, heating to 60 ℃, stirring, standing, separating, collecting crude aromatic ketone products, and carrying out vacuum rectification and purification to obtain high-purity aromatic ketone products. Finally obtaining the compound with the structural formula as follows:

the multifunctional aromatic ketone compound can be used for preparing a photocuring mixed system or a photocuring radiation material formula system, and can also be used for preparing a free radical photopolymerization initiator compound.

The invention also provides a photocured hybrid system comprising at least one polymerizable ethylenically unsaturated compound and a novel aromatic ketone photoinitiator system of the general formula (I).

Preferably, the photoinitiator of the aromatic ketone group defined by formula (I) is used in an amount varying from 0.01 to 20 parts per 100 parts by weight of the total amount of the ethylenically unsaturated substance. More preferably, the aromatic ketone photoinitiator defined by the general formula (I) is used in an amount of 0.5 to 10 parts, for example, 0.8, 1.0, 1.5, 2.0, 3.0, 4.0, 5.0, 6.0, 7.0, 8.0, 9.0 parts, etc., by mass.

The invention also provides a photocuring radiation material formula system, which has at least one of the following characteristics:

(1) containing at least one photoinitiator as defined by the general formula (I) or mixtures thereof;

(2) containing at least one photoinitiator as defined by the general formula (I) or in a mixture with other customary commercial photoinitiators;

(3) containing at least one ethylenically unsaturated compound, including compounds having free-radically polymerizable ethylenic unsaturation, which may be a reactive diluent (low molecular weight) or an oligomer (higher molecular weight),

(4) contains or contains functional additives or/and active auxiliary agents and the like required by partial performance. Including but not limited to polymerization inhibitors, leveling agents, defoamers, anti-sagging agents, thickeners, tackifiers, dispersants, solubilizers, diluents, antistatic agents, water or organic solvents, antimicrobials, flame retardants, reactive amine co-initiators, inorganic or organic fillers (e.g., carbonates, sulfates, titanium dioxide, etc.) and/or organic, inorganic colorants (e.g., pigments or dyes, etc.), ultraviolet absorbers or/and light stabilizers to enhance the weatherability of the coating ink, and suitable aqueous dispersions or water-soluble products of the above components, and the like.

Preferably, the ethylenically unsaturated compound is a reactive diluent or oligomer.

The novel UV radiation curing material formula system comprises a photo-curing coating or an ink material, and has very wide application value in various construction modes (such as spraying, rolling, curtain coating, wiping, dip-coating and the like) and/or construction procedures (such as putty, base coating, coloring, middle coating, surface coating and the like) and in downstream markets such as wood furniture, plastic products, printing and packaging, ink-jet printing, electronic consumer goods, automotive interior and exterior decorations, pipeline profiles, industrial terraces, building curtain walls, 3D printing additive manufacturing, ships or container bodies and the like.

In another aspect, the invention provides an application of the light-cured radiation material formula system, and the novel UV radiation-cured material formula system is applied to wood furniture, plastic products, printing and packaging, ink-jet printing, electronic consumer goods, automotive interior and exterior trim, pipeline profiles, industrial terraces, building curtain walls, 3D printing additive manufacturing and ship or container bodies.

The invention also provides a free radical photopolymerization initiator containing an ethylenic unsaturated system, which takes the mono-substituted or multi-substituted functionalized aromatic ketone compound as an effective component. Preferred embodiments include the use of such coatings or inks for the preparation of pigmented and unpigmented paints and varnishes, powder coatings, printing inks, printing plates, adhesives, pressure-sensitive adhesives, dental compositions, gel coats, photoresists for electronics, electrographic resists, etch resists, both liquid and dry films, solder resists, resists for the manufacture of color filters for various display applications, resists for the manufacture of structures in the manufacturing process for plasma display panels, electroluminescent displays and LCDs, for LCDs, holographic data storage, compositions for encapsulating electronic components, for the preparation of magnetic recording materials, micromechanical components, waveguides, optical switches, stencils, etch masks, color proofing systems, glass fiber cable coatings, screen printing stencils, for the production of three-dimensional objects by means of stereolithography, as image recording materials, a decolorizing material for holographic recording, microelectronic circuits, decolorizing materials, for image recording materials using microcapsules, as photoresist material for UV and visible laser direct imaging systems, as photoresist material for forming dielectric layers in sequential build-up layers of printed circuit boards; in particular, the photopolymerizable compositions described above are used for the preparation of pigmented and unpigmented paints and varnishes, powder coatings, printing inks (e.g. screen printing inks, inks for offset, flexo or inkjet printing), printing plates, adhesives, sealings, potting components, dental compositions, foams, moulding compounds, composite material compositions, glass fibre cable coatings, screen printing stencils for the production of three-dimensional objects by means of stereolithography, and as image recording materials, photoresist compositions, decolorizing materials for image recording materials, image recording materials using microcapsules.

The invention provides aromatic ketone compounds shown as a general formula (I), a photoinitiator for radiation curing of an alkene-containing unsaturated compound system, and application of a radiation curing material system containing the compounds. Compared with the existing products, the invention uses cheap and easily available industrial raw materials as a starting point breakthrough to prepare the mono-substituted or multi-substituted functional group aromatic ketone compound, applies the compound to the application of the photoinitiator in radiation curing, aims at solving the problems of toxicity and VOCs pollution of the photoinitiator and simultaneously strives for the economic competitiveness of the photoinitiator so as to reduce the overall cost and improve the photoinitiation efficiency.

Detailed Description

The invention relates to an aromatic ketone compound shown as a general formula (I), and the structure of the aromatic ketone compound is shown as the general formula (I). Wherein n is an integer between 1 and 5, R₁The radicals being substituents may be halogen atoms (F, Cl, Br, I), -NCO groups, N-alkyl, -CN groups, -NO₂Radical, -SO₃H sulfonic group, S-alkyl, Si-alkyl, alkenyl, alkynyl or aromatic ring group. R₂And R₃The groups are independent of each other, a branched or straight chain alkyl group with 1-12 carbon atoms, with or without a ring system structure, R₂And R₃The radicals may form a cyclic structure, R₂And R₃The radicals may also be substituted or interrupted by 1 to 4 oxygen, nitrogen, silicon or sulfur atoms.

The invention provides a preparation method of mono-substituted and multi-substituted functional aromatic ketone compounds with a general formula (I), which comprises two conditions: for the compound of the general formula (I), when the group R1 is an electron donating group, the reaction sequence is to complete the modification of the aromatic ring parent nucleus R1 and then carry out Friedel-crafts acylation reaction, and the purpose of the sequence is to increase the reaction yield and reduce the cost requirement. When the R1 group is an electron-withdrawing group, the reaction sequence is that the aromatic nucleus finishes Friedel-crafts acylation reaction and then carries out aromatic ring R1 modification or selects other modes to carry out preparation of mono-substituted or multi-substituted functional group aromatic ketone.

The present invention also provides a hybrid system which is radiation curable by light (ultraviolet, visible or equivalent light sources) comprising at least one polymerizable ethylenically unsaturated compound and a novel aromatic ketone photoinitiator system of the general formula (I) as defined in claim 1.

The invention also provides a novel formula system of the photocuring radiation material, which comprises the following components in part by weight:

1: containing at least one photoinitiator as defined by the general formula (I) or mixtures thereof;

2: containing at least one photoinitiator as defined by the general formula (I) or in a mixture with other customary commercial photoinitiators;

3: containing at least one ethylenically unsaturated compound (monomer or resin);

4: contains or partially contains functional additives or/and active auxiliary agents and the like required by performance. Including but not limited to polymerization inhibitors, leveling agents, defoamers, anti-sagging agents, thickeners, tackifiers, dispersants, solubilizers, diluents, antistatic agents, water or organic solvents, antimicrobials, flame retardants, reactive amine co-initiators, inorganic or organic fillers (e.g., carbonates, sulfates, titanium dioxide, etc.) and/or organic, inorganic colorants (e.g., pigments or dyes, etc.), ultraviolet absorbers or/and light stabilizers to enhance the weatherability of the coating ink, and suitable aqueous dispersions or water-soluble products of the above components, and the like.

The following examples illustrate that the above mono-and poly-substituted functional aromatic ketones and photoinitiator systems comprising mixtures of such compounds can be used as initiators for free radical photopolymerization of ethylenically unsaturated compounds or mixtures of ethylenically unsaturated compounds. The present invention is described in detail below by way of specific examples, it being understood that the following examples are intended only by way of illustration and description and are not intended to limit the scope of the present invention in any way.

Example 1 preparation example 1

The specific operation steps are as follows:

under the protection of nitrogen, 300 liters of anhydrous chlorobenzene is put into a reaction kettle, stirring is started, the temperature is reduced, 130 kg of aluminum trichloride is put into the reaction kettle, stirring and temperature reduction are kept for 1 hour, then 100 kg of isobutyryl chloride is dripped into the reaction kettle, the dripping time is 2 hours, the temperature of the reaction kettle is kept lower than 5 ℃, and after the dripping is finished, stirring is continued for 6 hours to obtain a Friedel-crafts acylation intermediate. Then through the alternative two-stage series arrangement of the primary and secondary chlorinated kettles, firstly, 400 kg of Friedel-crafts acylation intermediates are respectively put into the primary and secondary chlorinated kettles, chlorine is led into the primary kettle, the chlorine is led into the secondary kettle after being absorbed by the primary kettle for environment-friendly absorption again, after 150 kg of chlorine is led, the chlorine is stopped to be led into the primary kettle, nitrogen is led into the primary kettle for 20 min to replace excessive chlorine, then the chlorinated intermediates in the primary kettle are collected, and at the same time, 400 kg of Friedel-crafts acylation intermediates are put into the primary kettle again, and the primary kettle is changed into the secondary kettle for repeated operation. And (3) putting the chlorinated intermediate into a hydrolysis kettle, adding 300 kg of 35% sodium hydroxide solution, heating to 60 ℃, stirring for 3 hours, standing, separating, collecting crude aromatic ketone products, and carrying out vacuum rectification and purification to obtain aromatic ketone products with the purity of 99%.

¹H NMR(300MHz,CDCl3),δ:I.36(6H,s),7.16(2H,dd),8.18(2H,dd)。

Example 2 preparation example 2

Under the protection of nitrogen, 300 liters of anhydrous chlorobenzene is put into a reaction kettle, stirring is started, the temperature is reduced, 130 kg of aluminum trichloride is put into the reaction kettle, stirring and temperature reduction are kept for 1 hour, then 135 kg of cyclohexanecarboxyl chloride is dripped into the reaction kettle, the dripping time is 2 hours, the temperature of the reaction kettle is kept lower than 5 ℃, and after the dripping is finished, stirring is continued for 6 hours to obtain a Friedel-crafts acylated intermediate. Then through the alternative two-stage series arrangement of the primary and secondary chlorinated kettles, firstly, 400 kg of Friedel-crafts acylation intermediates are respectively put into the primary and secondary chlorinated kettles, chlorine is led into the primary kettle, the chlorine is led into the secondary kettle after being absorbed by the primary kettle for environment-friendly absorption again, after the chlorine is led into 130 kg, the chlorine is stopped to be led into the primary kettle, nitrogen is led into the primary kettle for 20 min to replace excessive chlorine, then the chlorinated intermediates in the primary kettle are collected, and at the same time, 400 kg of Friedel-crafts acylation intermediates are put into the primary kettle again, and the primary kettle is changed into the secondary kettle for repeated operation. Adding the chlorinated intermediate into a hydrolysis kettle, adding 300 kg of 35% sodium hydroxide solution, heating to 60 ℃, stirring for 3 hours, standing, separating, collecting crude aromatic ketone products, and carrying out vacuum rectification and purification to obtain aromatic ketone products with the purity of 99%, wherein the yield is 88%;

¹H NMR(300MHz,CDCl3),δ:I.36(1H,m),I.67-1.79(7H,m),2.02(2H,m),7.16(2H,d d),8.18(2H,dd)。

example 3 preparation example 3

Mixing concentrated nitric acid and concentrated sulfuric acid to obtain a mixed solution, adding trichloromethyl benzene into a reaction kettle, stirring and dropwise adding the mixed solution at the temperature of 50-55 ℃, wherein the dropwise adding time is 50-60min, continuously stirring for 15-20h after the dropwise adding is finished to obtain an intermediate trichloro compound, dissolving 100 kg of purified trichloro compound into dry tetrahydrofuran, dropwise adding 10.5 kg of magnesium chips and dry tetrahydrofuran suspension at the temperature of 25 ℃ below the temperature of the reaction solution, slowly dropwise adding 27 kg of dry acetone after the reaction is finished, stirring for 2 h, adding water, continuously stirring for 30 min, collecting an organic phase, and carrying out reduced pressure rectification to obtain a nitro-substituted aromatic ketone product with the yield of 78%.

¹H NMR(300MHz,CDCl3),δ:I.36(6H,s),8.34(2H,dd),8.42(2H,dd)。

Example 4 preparation example 4

300 kg of chlorinated aromatic ketone in example 1 is added into a reaction kettle, the kettle temperature is kept at 85 +/-5 ℃, 20-30% of sodium methyl mercaptide aqueous solution and 60% of tetramethyl ammonium bromide aqueous solution are added, the kettle temperature is maintained for reaction for 10 hours, and the feed liquid is filtered and cooled to crystallize to obtain the methylthio substituted aromatic ketone with the yield of 93%.

Example 5 preparation example 5

500 kg of MCl₃Dissolving in 500L dichloroethane solvent, adding 125 Kg of 2-hydroxy-2-methyl-1-phenyl-1-propyl ketone, controlling the temperature to 50 ℃, adding 160 Kg of paraformaldehyde, reacting for 8 hours at 50-60 ℃, cooling to room temperature after the reaction is finished, adding into 250 Kg of 10% hydrochloric acid aqueous solution, layering, washing with organic phase secondary water and saturated sodium chloride, separating an organic layer, evaporating the organic solvent under reduced pressure to obtain a chloromethyl intermediate, adding the chloromethyl intermediate into 230Kg of 20-25% sodium hydroxide aqueous solution, stirring for reaction until the chloromethyl aromatic ketone is completely reacted, and distilling under high vacuum to obtain the hydroxymethyl substituted aryl ketone product. The yield thereof was found to be 67%.

¹H NMR(300MHz，CDCl3)，δ：7.86(2H，d)，7.15(2H，d)，5.2(1H，s)，4.3(1H，s)，I.59(6H，s)。

Example 6: evaluation of Performance

By formulating the exemplary photocurable compositions, the photoinitiators of formula I of the present invention were evaluated for various applications, including storage cure rate, odor, and the like.

1. Preparation of Photocurable compositions

The application example is as follows:

TABLE 1

Components	Proportioning
		Epoxy acrylic resin B-100	35
Polyurethane acrylic resin B-520	30
		Tripropylene glycol diacrylate	30
Defoaming agent BYK-057	0.5
		Wetting agent BYK-34	0.5
Leveling agent BYK-3500	0.5
		Photoinitiator	3.5

In the composition, the photoinitiator is a hydroxyketone photoinitiator shown in a general formula I disclosed by the invention or a comparative photoinitiator known in the prior art, and all the components are in parts by mass.

The addition amount of the photoinitiator in the photocuring composition system is known formula experience addition amount, and the dosage of the photoinitiator in different composition systems needs to be adjusted according to the overall activity of the composition system and the requirements of the composition system, and can be determined according to actual requirements. For example, the amount of the aromatic ketone photoinitiator defined by the general formula (I) varies from 0.01 to 20 parts, and more preferably, the amount of the aromatic ketone photoinitiator defined by the general formula (I) is from 0.5 to 10 parts, per 100 parts by weight of the total amount of the ethylenically unsaturated material.

2. Rate of cure

The above composition was coated on white cardboard using a 22 μm wire bar coater to compare the performance of the photoinitiators 1173, 184, MBF and the compounds of the examples of the invention as photoinitiators. The coated sample was mounted on a belt and transported under a medium pressure mercury lamp. Repeated indentation and scratching with fingernails did not produce prints as a complete cure standard, determining the belt speed for a fully cured sample.

3. Odor grade

The photocurable composition was completely cured according to the above-mentioned curing method and curing speed. The residual odor test takes 5 persons as independent evaluation odor grades, and takes more than or equal to 3 persons as a standard for similar or uniform evaluation of odor grades.

The criteria for evaluation are numerically expressed as follows:

a level: no smell was felt;

b stage: very mild odor;

c level: a slight odor;

d stage: a noticeable odor;

e, grade: a strong odor;

f grade: very strong odor

4. Adhesion test

The adhesiveness is tested by adopting a grid marking method according to the test standard GB/T9286-1998 and is evaluated according to the 0-5 level standard;

the evaluation results are shown in table 2:

TABLE 2

Photoinitiator	Speed of curing	Odor grade	Yellowing (Delta E)	Adhesion and light transmittance
					Example one	98	B-C	0.13	0/paint film is clear and not turbid
Example two	100	B-C	0.14	0/paint film is clear and not turbid
					EXAMPLE III	102	B-C	0.13	0/paint film is clear and not turbid
Example four	120	C-D	0.15	0/paint film is clear and not turbid
					EXAMPLE five	92	B-C	0.15	0/paint film is clear and not turbid
Darocur 1173	90	D-E	0.31	2/cloudy, dull and cloudy film
					Irgacure 184	93	D-E	0.22	1/paint film slightly cloudy and dull
MBF	72	C-D	0.16	0/paint film is clear and not turbid

Wherein MBF is a photoinitiator, the Chinese name is methyl benzoylformate, and the Chinese name is methyl benzoylate.

As can be seen from the results in Table 2, the photocurable composition containing the novel hydroxy ketone photoinitiator represented by the general formula I has good photoinitiation activity, the photoinitiation activity is higher than that of 1173/184/MBF which is commercially available at present, the yellowing resistance is competitive with that of 1173/184/MBF, and the low-odor environment-friendly performance is also shown; under the requirement of fixed activity, the addition amount of the photoinitiator shown in the general formula (I) is lower, the cost can be effectively reduced, the yellowing resistance is improved, the environmental protection performance of low odor is realized, and the application range of the initiator structure shown in the general formula (I) is expanded.

In conclusion, compared with the known similar photoinitiators sold in the market, the novel hydroxy ketone photoinitiator disclosed by the invention has more excellent application performance, and can greatly improve the performance of the known photocuring product or develop new application in the field.

It is emphasized that the above-listed compounds are merely some preferred exemplary structures and should not be considered limiting structures. Any variation in the reaction conditions or parameter adjustments that may be routinely altered or optimized by those skilled in the art of radiation photocuring based on the disclosure of this application is within the scope of the present invention.