TW202402862A - Urethane (meth) acrylate and photocurable resin composition containing the same - Google Patents

Abstract

The present invention provides a urethane (meth)acrylate obtained by reacting 75 to 90% by mass of a polyoxyalkylene derivative (A) represented by the following formula (1), 10 to 25% by mass of a polyisocyanate compound (B) represented by the following formula (2), and 0 to 5% by mass of a dihydroxy compound (C) represented by the following formula (3), and a photocurable resin composition containing the urethane (meth)acrylate (the definition of a symbol in the following formula is as described in the specification). HO - (R3O) p -H (3).

Description

Urethane (meth)acrylate and photocurable resin composition containing the same

The present invention relates to urethane (meth)acrylate and a photocurable resin composition containing the same.

Photocurable resins are widely used in various applications such as coating materials such as hard coat layers, manufacturing three-dimensional molded objects, and photoresists. Among them, urethane (meth)acrylate is one of the representative photocurable resins. As the uses of photocurable resin compositions expand and the physical properties required of photocurable resin compositions become more advanced or diversified, Urethane (meth)acrylates and photocurable resin compositions containing them are required to form films or layers that are excellent in various properties such as mechanical strength and flexibility.

For example, the photoresist material used for etching in the manufacturing of printed wiring boards or plating in the field of metal precision processing uses a photosensitive element, and the photosensitive element is a layer composed of a photosensitive resin composition (hereinafter referred to as "photosensitive layer"). "), support film, and protective film as needed.

The pattern formation of the printed wiring board is performed by a development step. In development using a negative photoresist, a mask is used on the above-mentioned photosensitive layer and active energy rays are irradiated to reveal the difference in solubility between the exposed and unexposed parts, and the unexposed parts are dissolved with a solvent, thereby forming a pattern of a specific shape. . In recent years, with the The miniaturization of electronic products, the refinement of integrated circuits, and the high definition of display devices require the formation of fine patterns. Therefore, it is required to have an excellent residual film rate of the undissolved portion of the developer when forming the pattern.

Photosensitive elements are sometimes used in a roll form. However, when rolled into a roll, the photosensitive layer will bend, so the photosensitive layer needs to be flexible. In addition, some parts of the photosensitive layer may be whitened due to bending, which may cause poor quality of the product. Therefore, performance that does not cause whitening is also required. In addition, when the through-holes provided on the substrate are covered with a photosensitive layer like a multilayer wiring board, the photocurable resin composition is required to form a photosensitive layer that is not cracked by the spray pressure of a developer or water wash. Generally speaking, if the mechanical strength is increased, the flexibility will deteriorate. However, in order to meet all the above requirements, a photosensitive layer with excellent flexibility and mechanical strength, which is inversely related, is required.

In addition, forming a photosensitive layer on a support film is generally performed by coating a solution-like photocurable resin composition on the support film. However, if the viscosity of the composition is too high at this time, the composition cannot be uniformly coated. On the contrary, if the viscosity is too high, the photosensitive layer will not be uniformly coated. If it is low, the film formed by the composition will become thinner and the desired properties such as strength cannot be obtained. Therefore, photocurable resin compositions are also required to control rheological thixotropy.

In response to these requirements, various photocurable resin compositions have been studied in the past. For example, Patent Document 1 discloses a photosensitive resin composition that combines a binder polymer with a dispersion (weight average molecular weight/number average molecular weight) of 1.6 or less and a specific photopolymerizable compound, thereby forming a resolution or Pattern with excellent flexibility. However, the photosensitive resin composition described in Patent Document 1 has insufficient residual film rate and thixotropic properties. Patent Document 2 discloses a photosensitive photoresist liquid having thixotropy, but does not examine flexibility. Patent Document 3 discloses the formation of a film that does not whiten when bent by using a specific acrylic resin composition, but does not examine the remaining film rate or thixotropy.

[Prior technical literature]

[Patent Document]

Patent Document 1: Japanese Patent Application Publication No. 2013-109323.

Patent Document 2: Japanese Patent Application Publication No. 2005-152736.

Patent Document 3: Japanese Patent Application Publication No. 2020-147653.

An object of the present invention is to provide a photocurable resin composition which has excellent residual film rate after development, flexibility and mechanical strength, can form a film that does not whiten when wound into a roll, and has excellent thixotropy.

The present inventors conducted studies to solve the above-mentioned problems, and found that the above-mentioned problems can be solved by using a specific urethane (meth)acrylate. The present invention based on this discovery is as follows.

[1] An urethane (meth)acrylate containing 75 to 90% by mass of the polyoxyalkylene derivative (A) represented by the formula (1) and 10 to 25% of the polyisocyanate compound (B) represented by the formula (2) It is formed by reacting 0 to 5 mass% of the dihydroxy compound (C) represented by formula (3).

(In the formula, R ¹ is a hydrogen atom or a methyl group, l, m and n represent the average degree of polymerization respectively, l is a number from 1 to 20, m is a number from 0 to 15, and n is a number from 1 to 10)

(In the formula, 3 R ² are each independently an alkylene group having 1 to 10 carbon atoms)

HO-(R ³ O)pH (3)

(In the formula, R ³ is an alkylene group having 2 to 4 carbon atoms, and p represents the average degree of polymerization and is a number from 1 to 5).

In addition, the amounts of the aforementioned components in the reaction of the aforementioned [1] are all relative to the total of the aforementioned polyoxyalkylene derivative (A), the aforementioned polyisocyanate compound (B), and the aforementioned dihydroxy compound (C) (hereinafter referred to as "reaction"). "total of things") value.

[2] A photocurable resin composition containing:

35 to 60 mass% of urethane (meth)acrylate as described in the aforementioned [1];

35 to 60% by mass of (meth)acrylic polymer with an acid value of 50 to 300 mgKOH/g; and

Photopolymerization initiator 0.1 to 5% by mass.

Hereinafter, the photocurable resin composition of [2] mentioned above is called "photocurable resin composition (I)". In addition, the contents of the aforementioned components in the photocurable resin composition (I) are all relative to the total of the aforementioned urethane (meth)acrylate, the aforementioned (meth)acrylic polymer, and the aforementioned photopolymerization initiator (hereinafter The value called "Total of components (I)").

[3] A photocurable resin composition containing:

30 to 50 mass% of urethane (meth)acrylate as described in the aforementioned [1];

0.01 to 10 mass% of polyoxyalkylene derivative (A) represented by formula (1);

40 to 60% by mass of (meth)acrylic polymer with an acid value of 50 to 300 mgKOH/g; and

Photopolymerization initiator 0.1 to 5% by mass.

(In the formula, R ¹ is a hydrogen atom or a methyl group, l, m and n respectively represent the average degree of polymerization, l is a number from 1 to 20, m is a number from 0 to 15, and n is a number from 1 to 10).

Hereinafter, the photocurable resin composition of [3] mentioned above is called "photocurable resin composition (II)". Furthermore, the contents of the aforementioned components in the photocurable resin composition (II) are relative to the aforementioned urethane (meth)acrylate, the aforementioned polyoxyalkylene derivative (A), the aforementioned (meth)acrylic polymer, and The value of the total of the aforementioned photopolymerization initiators (hereinafter referred to as "total of components (II)").

If the urethane (meth)acrylate of the present invention is used, a photocurable resin composition can be obtained, which has excellent residual film rate after development, flexibility and mechanical strength, and can form a film that does not whiten during winding. Excellent thixotropy.

The embodiments of the present invention will be described in detail below. However, the present invention is not limited to the following forms.

In this specification, "(meth)acrylate" means acrylate or methacrylate. Here, only one type of (meth)acrylate may be used, or two or more types may be used in combination. Therefore, when two or more (meth)acrylates may exist, "(meth)acrylate" is acrylate and/or methacrylate. Terms such as "(meth)acrylic acid" are also synonymous with "(meth)acrylate".

In this specification, "polyethylene glycol chain" refers to polyoxyethylene chain, "polypropylene glycol chain" refers to polyoxypropyl chain, "polybutylene glycol chain" refers to polyoxybutyl chain, and "polytetramethylene glycol chain" refers to polyoxybutyl chain. "Based glycol chain" is a polyoxytetramethylene chain.

In this specification, "propylene" refers to propanediyl, and "butylene" refers to butanediyl. Therefore, both the propylene group and the butylene group may be linear or branched.

[Polyoxyalkylene derivative (A)]

The polyoxyalkylene derivative (A) used in the present invention is a compound represented by formula (1).

(In the formula, R ¹ is a hydrogen atom or a methyl group, l, m and n represent the average degree of polymerization respectively, l is a number from 1 to 20, m is a number from 0 to 15, and n is a number from 1 to 10)

Only one type of polyoxyalkylene derivative (A) may be used, or two or more types may be used in combination.

From the viewpoint of improving the flexibility of urethane (meth)acrylate, R ¹ is preferably a methyl group.

In formula (1), l, m and n are the average values of oxyethylene (C ₂ H ₄ O), oxypropyl (C ₃ H ₆ O) and oxybutyl (C ₄ H ₈ O) respectively. degree of polymerization. Therefore, l, m and n can all be decimals. In addition, (C ₃ H ₆ O) is an arbitrary structural unit, and m may be 0.

l is 1 to 20, preferably 4 to 17, more preferably 6 to 15, and still more preferably 8 to 12. m is 0 to 15, preferably 0 to 10, more preferably 0 to 5, still more preferably 0 to 2, and particularly preferably 0. n is 1 to 10, preferably 2 to 9, more preferably 3 to 8, still more preferably 4 to 6. By using the polyoxyalkylene derivative (A) in which l, m, and n are within the aforementioned ranges, the residual film rate of the film formed of the photocurable resin composition can be increased while maintaining the flexibility.

In addition, the butylene group may be either linear or branched, but from the viewpoint of flexibility and residual film rate of the film formed of the photocurable resin composition, linear elongation is preferred. butyl. That is, (C ₄ H ₈ O) in formula (1) is preferably oxytetramethylene.

Also, C ₂ H _{4 O} , C ₃ H ₆ O and C ₄ H ₈ O in -(C ₂ H ₄ O) l -(C ₃ H ₆ O) _m -(C ₄ H ₈ O) _n - can be They may exist randomly or may form blocks. In addition, the order of arrangement is not particularly limited and may be different from the order described in formula (1).

As the polyoxyalkylene derivative (A), a commercially available product or a synthetic one may be used. In order to form a film excellent in flexibility, residual film ratio, and mechanical strength, the polyoxyalkylene derivative (A) is preferably one in which R ¹ is a methyl group, m is 0, and C ₄ H ₈ O is an oxytetramethylene group. Ethylene glycol tetramethylene glycol monomethacrylate. In addition, C ₂ H ₄ O and C ₄ H ₈ O in polyethylene glycol tetramethylene glycol monomethacrylate may exist randomly as mentioned above, or may form blocks, and their arrangement order is not the same. No special restrictions.

[Polyisocyanate compound (B)]

The polyisocyanate compound (B) used in the present invention is a compound represented by formula (2).

(In the formula, 3 R ² are each independently an alkylene group having 1 to 10 carbon atoms)

As for the polyisocyanate compound (B), only one type may be used or two or more types may be used in combination.

The three R ^2's in the formula (2) may be the same or different respectively. From the viewpoint of easy availability, the three R ^2's are preferably the same. The alkylene group of R ² may be linear or branched, preferably linear.

The carbon number of R ² is preferably 3 to 9, more preferably 4 to 8, still more preferably 5 to 7. By using a polyisocyanate compound (B) in which the carbon number of R ² is within the aforementioned range, the mechanical strength and residual film rate of the film formed of the photocurable resin composition can be improved while maintaining the flexibility.

As the polyisocyanate compound (B), a commercially available product or a synthetic one may be used. Examples of the polyisocyanate compound (B) include diisocyanate trimer (that is, diisocyanate terpolymer) (for example, DURANATE TPA-100 and DURANATE TKA-100 manufactured by Asahi Kasei Chemical Co., Ltd.). From the viewpoint of the residual film rate of the film formed of the photocurable resin composition, the polyisocyanate compound (B) is particularly preferably hexamethylene diisocyanate-triisocyanate (that is, hexamethylene diisocyanate-triisocyanate). polymer).

[Dihydroxy compound (C)]

The dihydroxy compound (C) used in the present invention is a compound represented by formula (3).

HO-(R ³ O)pH (3)

(In the formula, R ³ is an alkylene group having 2 to 4 carbon atoms, and p represents the average degree of polymerization and is a number between 1 and less than 5)

Only one type of dihydroxy compound (C) may be used or two or more types may be used in combination. In addition, the dihydroxy compound (C) is an optional component, and the amine ester (methyl ester) of the present invention may be produced without using the dihydroxy compound (C). )Acrylate.

The alkylene group of R ³ may be linear or branched. The carbon number of R ³ is preferably 2 to 4, more preferably 2 to 3, and still more preferably 2. By using a dihydroxy compound (C) in which the carbon number of R ³ is within the aforementioned range, the residual film rate of the film formed of the photocurable resin composition can be increased.

p is the average degree of polymerization, so it can be a decimal. p is preferably 1 to 4, more preferably 1 to 3, and still more preferably 2. By using the dihydroxy compound (C) in which p is within the aforementioned range, the residual film rate of the film formed of the photocurable resin composition can be increased.

From the viewpoint of the residual film rate of the film, the dihydroxy compound (C) is particularly preferably diethylene glycol.

[Urethane (meth)acrylate]

The urethane (meth)acrylate of the present invention is prepared by making the polyoxyalkylene derivative (A) 75 to 90 mass %, the polyisocyanate compound (B) 10 to 25 mass %, and the dihydroxy compound (C) 0 to 25 mass %. Obtained from 5 mass% amine esterification reaction.

The amount of the polyoxyalkylene derivative (A) in the aforementioned amine esterification reaction is preferably 78 to 89 mass%, more preferably 79 to 88 mass%, and still more preferably 81 to 86 mass% relative to the total amount of reactants. , the best is 83 to 85 mass%.

The amount of the polyisocyanate compound (B) in the aforementioned amine esterification reaction is preferably 11 to 22 mass%, more preferably 12 to 21 mass%, and more preferably 14 to 19 mass% relative to the total amount of reactants. Preferably, it is 15 to 17% by mass.

The amount of the dihydroxy compound (C) in the aforementioned amine esterification reaction is preferably 0 to 4% by mass, more preferably 0 to 3% by mass, and still more preferably 0.01 to 2% by mass relative to the total amount of reactants. Preferably, it is 0.1 to 1% by mass.

By reacting each component in an amount within the aforementioned range, the urethane (meth)acrylate of the present invention can be produced with good productivity without causing residue or gelation of the raw materials, while maintaining light. The flexibility of the film formed from the curable resin composition improves its mechanical strength or residual film rate.

The aforementioned amine esterification reaction is preferably carried out in the presence of a catalyst and a polymerization inhibitor. Examples of the amine esterification catalyst include cobalt naphthenate, zinc naphthenate, tin (II) chloride, tin (IV) chloride, tetra-n-butyltin, tri-n-butyltin acetate, n-butyltin trichloride, trimethyl Tin hydroxide, dimethyltin dichloride, dibutyltin acetate, dibutyltin dilaurate, dibutyltin diethylhexanoate, dibutyltin sulfite, tin octenate, etc. Only one type of catalyst may be used or two or more types may be used in combination. When a catalyst is used, its amount is preferably 10 to 1,000 ppm (mass basis) relative to the total amount of reactants.

等胺類；二硫苯甲醯基硫化物、二苄基四硫化物等硫化物類等。聚合抑制劑可僅使用1種或併用2種以上。 Examples of polymerization inhibitors include hydroquinone, hydroquinone monomethyl ether, mono-tert-butyl hydroquinone, catechol, p-tert-butyl catechol, 2,6-di Phenols such as tert-butyl-m-cresol, 2,6-di-tert-butyl-4-methylphenol, pyrogallol, β-naphthol; benzoquinone, 2,5-diphenyl-p- Quinones such as benzoquinone, p-methylquinone, p-quinone, etc.; nitrobenzene, m-dinitrobenzene, 2-methyl-2-nitrosopropane, α-phenyl-tert-butylnitrone, 5, 5-Dimethyl-1-pyrroline-1-oxide and other nitro compounds or nitroso compounds; tetrachloroquinoneamine, diphenylamine, diphenyltrinitrophenylhydrazine, phenol-α-naphthylamine, Pyridine, thiophene

and other amines; sulfides such as disulfide benzyl sulfide and dibenzyl tetrasulfide, etc. As a polymerization inhibitor, only one type may be used or two or more types may be used in combination.

When a polymerization inhibitor is used, its amount is preferably 10 to 10,000 ppm (mass basis) based on the total amount of reactants, more preferably 100 to 1,000 ppm. If the polymerization inhibitor amount is less than 10 ppm, a sufficient polymerization inhibitory effect may not be obtained. If it exceeds 10,000 ppm, various physical properties of the obtained urethane (meth)acrylate may be adversely affected.

The reaction temperature in the aforementioned amine esterification reaction is preferably 20 to 90°C, and the reaction time is preferably 1 to 30 hours. If the reaction temperature is lower than 20°C or the reaction time is less than 1 hour, the yield of the intended urethane (meth)acrylate is likely to be reduced. On the other hand, if the reaction temperature exceeds 90°C or the reaction time exceeds 30 hours, coloring or side reactions of the urethane (meth)acrylate tend to occur easily.

Organic solvents can be used in the aforementioned amine esterification reaction. Examples of organic solvents include aromatic hydrocarbon solvents such as toluene and xylene; ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone; ethyl acetate, propyl acetate, isobutyl acetate, Ester solvents such as butyl acetate, etc.

The end point of the amine esterification reaction can be confirmed by an infrared absorption spectrum showing the disappearance of the isocyanate group at 2270 cm ^-1 or by determining the content of the isocyanate group according to the method described in JIS K 7301. In the latter method, the isocyanate group content is calculated and ends when it becomes 0.5 mass% or less of urethane (meth)acrylate, preferably 0.1 mass% or less.

[Photocurable resin composition]

The present invention provides a photocurable resin composition (I), which contains:

Aminoester (meth)acrylate of the present invention;

(meth)acrylic polymer with an acid value of 50 to 300 mgKOH/g; and

Photopolymerization initiator.

Furthermore, the present invention provides a photocurable resin composition (II) containing:

Aminoester (meth)acrylate of the present invention;

The polyoxyalkylene derivative (A) represented by the aforementioned formula (1);

(meth)acrylic polymer with an acid value of 50 to 300 mgKOH/g; and

Photopolymerization initiator.

Each component in the photocurable resin composition (I) and (II) is described in order below. Only one type of each component may be used, or two or more types may be used in combination. In the following, "photocurable resin compositions (I) and (II)" are collectively referred to as "photocurable resin compositions of the present invention".

The description of the urethane (meth)acrylate of the present invention is as described above. The content of the urethane (meth)acrylate of the present invention in the photocurable resin composition (I) is 35 to 60 mass %, preferably 43 to 57 mass %, more preferably, based on the total components (I). It is 47 to 53% by mass.

The content of the urethane (meth)acrylate of the present invention in the photocurable resin composition (II) is 30 to 50 mass%, preferably 40 to 50 mass%, and more preferably 44 to 50% by mass.

By adjusting the content of the urethane (meth)acrylate of the present invention to the aforementioned range, the mechanical strength and residual film rate of the film formed of the photocurable resin composition can be improved while maintaining the flexibility.

The description of the polyoxyalkylene derivative (A) in the photocurable resin composition (II) is the same as the description of the [polyoxyalkylene derivative (A)]. From the viewpoint of imparting flexibility to the film without impairing the thixotropy of the composition and the mechanical strength of the resulting film, the content of the polyoxyalkylene derivative (A) in the photocurable resin composition (II) is relative to the component The total (II) is 0.01 to 10 mass%, preferably 0.1 to 8 mass%, more preferably 1 to 6 mass%. If the content is less than 0.01% by mass, the flexibility of the film cannot be improved, and if it exceeds 10% by mass, the mechanical strength of the film will decrease.

The photocurable resin composition of the present invention contains a (meth)acrylic polymer with an acid value of 50 to 300 mgKOH/g. By using such a (meth)acrylic polymer, the developability when developing using an alkali solution can be improved. In this specification, a "(meth)acrylic polymer" is a polymer which has a structural unit derived from (meth)acrylic acid. From the viewpoint of developability, the acid value of the (meth)acrylic polymer is preferably 80 to 180 mgKOH/g, more preferably 100 to 150 mgKOH/g.

The (meth)acrylic polymer is preferably a copolymer of (meth)acrylic acid and (meth)acrylic acid alkyl ester. In addition, the "alkyl group" in this specification also includes a cycloalkyl group. Only one type or two or more types of (meth)acrylic acid and (meth)acrylic acid alkyl ester may be used. Examples of (meth)acrylic acid alkyl esters include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, butyl (meth)acrylate, and amyl (meth)acrylate. Hexyl (meth)acrylate, cyclohexyl (meth)acrylate, heptyl (meth)acrylate, octyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, etc. The (meth)acrylic polymer is more preferably a copolymer of (meth)acrylic acid, cyclohexyl (meth)acrylate and methyl (meth)acrylate, and more preferably is methacrylic acid or cyclohexyl methacrylate. Copolymer of hexyl ester and methyl methacrylate.

From the viewpoint of the mechanical strength and flexibility of the film formed of the photocurable resin composition, the weight average molecular weight of the (meth)acrylic polymer is preferably 10,000 to 100,000, and more preferably 10,000 to 100,000. The best range is 15,000 to 80,000, and the best range is 20,000 to 60,000. The weight average molecular weight mentioned above is a value measured by gel permeation chromatography (GPC).

The content of the (meth)acrylic polymer in the photocurable resin composition (I) is 35 to 60 mass %, preferably 39 to 56.5 mass %, more preferably 44 to 44 mass % based on the total components (I). 52% by mass.

The content of the (meth)acrylic polymer in the photocurable resin composition (II) is 40 to 60 mass %, preferably 43 to 57 mass %, more preferably 46 to 46 mass % with respect to the total components (II). 54% by mass.

By adjusting the content of the (meth)acrylic polymer to the above range, the mechanical strength and residual film rate of the film formed of the photocurable resin composition can be improved while maintaining the flexibility.

啉基-丙酮-1(例如BASF公司製IRGACURE 907)、2-苄基-2-二甲胺基-1(4-

啉基苯基)-丁酮-1、雙(2,4,6-三甲基苯甲醯基)-苯基膦氧化物、苄基甲酸甲酯等。 The photocurable resin composition of the present invention contains a photopolymerization initiator. Examples of the photopolymerization initiator include isopropyl benzoin ether, isobutyl benzoin ether, diphenyl ketone, Michelone, o-benzoyl methyl benzoate, acetophenone, 2,4- Diethylthioxanthone, 2-chlorothioxanthone, ethyl anthraquinone, isoamyl p-dimethylaminobenzoate, ethyl p-dimethylaminobenzoate, 1-hydroxycyclohexylphenyl ketone (e.g. IRGACURE 184 manufactured by BASF Corporation), 2-hydroxy-2-methyl-1-phenyl-propan-1-one (for example, DAROCURE 1173 manufactured by BASF Corporation), 2,2-dimethoxy-1,2-diphenyl ethane-1-one (for example, IRGACURE 651 manufactured by BASF), 2-methyl-1-[4-(methylthio)phenyl]-2-N-

Phino-acetone-1 (for example, IRGACURE 907 manufactured by BASF), 2-benzyl-2-dimethylamino-1 (4-

Phinyl phenyl)-butanone-1, bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, methyl benzylformate, etc.

The content of the photopolymerization initiator in the photocurable resin composition (I) is 0.1 to 5 mass%, preferably 0.5 to 4 mass%, and more preferably 1 to 3 mass% relative to the total component (I).

The content of the photopolymerization initiator in the photocurable resin composition (II) is 0.1 to 5 mass%, preferably 0.5 to 4 mass%, and more preferably 1 to 3 mass% relative to the total component (II).

By adjusting the content of the photopolymerization initiator to the aforementioned range, the mechanical strength of the film formed of the photocurable resin composition can be improved while maintaining flexibility.

Solvents or other components may be added to the photocurable resin composition of the present invention within the scope that does not impair the effects of the present invention.

Any known solvent can be used as the solvent, and examples thereof include methanol, ethanol, ethyl acetate, butyl acetate, acetone, methyl ethyl ketone, N,N-dimethylformamide, tetrahydrofuran, benzene, toluene, and diethylene glycol. Alcohol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol ethyl methyl ether, propylene glycol monomethyl ether, ethylene glycol acetate monomethyl ether, acetate propylene glycol monomethyl ether, etc. Only one type of solvent may be used or two or more types may be used in combination.

When a solvent is used, the content of the solvent in the photocurable resin composition (I) is preferably 35 to 60 mass%, more preferably 40 to 60 mass%, and still more preferably 35 to 60 mass% relative to the entire photocurable resin composition (I). It is 45 to 55% by mass.

When a solvent is used, the content of the solvent in the photocurable resin composition (II) is preferably 35 to 65 mass%, more preferably 40 to 60 mass%, and still more preferably 35 to 65 mass% relative to the entire photocurable resin composition (II). It is 45 to 55% by mass.

By adjusting the content of the solvent to the aforementioned range, the mechanical strength or residual film rate of the film formed of the photocurable resin composition can be improved while maintaining the flexibility.

Examples of other ingredients include heat-resistant enhancers, leveling agents, development aids, inorganic fine particles, coupling agents, fillers, epoxy resins, phenol resins, thermosetting resins such as polyvinylphenol, hardeners, plasticizers, and polymerization inhibitors. Agents, antioxidants, defoaming agents, viscosity adjusters, pigments, etc. Only one type of other ingredients may be used, or two or more types may be used in combination.

The photocurable resin composition of the present invention can be applied to a base material by a known method. Examples of such methods include dip coating, spray coating, flow coating, shower coating, roller coating, spin coating, and brush coating.

A cured film can be formed by irradiating the photocurable resin composition of the present invention with active energy rays such as ultraviolet rays, visible rays, radiation rays, and electron beams. For photohardening, a high-pressure mercury lamp, a metal halide lamp, etc. can be used. The environment for irradiating light can be air or inert gases such as nitrogen and argon.

(Example)

Examples and comparative examples are listed below to further describe the aforementioned embodiments in detail.

(Synthesis of urethane (meth)acrylate)

(Synthesis example 1)

Polyethylene glycol tetramethylene glycol monomethacrylate (manufactured by NOF Corporation, trade name: BLEMMER 55PET- 800, R ¹ in formula (1) is methyl, l is about 10, m is 0, n is about 5, C ₂ H ₄ O and C ₄ H ₈ O exist randomly) 300g, as an amine esterification contact 0.05g of dibutyltin dilaurate was used as a mediating agent, and 0.05g of 2,6-di-tert-butyl-4-methylphenol was used as a polymerization inhibitor. The polyisocyanate compound (B) (tripolyisocyanate of hexamethylene diisocyanate manufactured by Asahi Kasei Chemical Co., Ltd., trade name : DURANATE TPA-100, isocyanate group content: 23.1 mass%) 57.1g was added to the aforementioned flask, and the reaction was carried out while maintaining it at 70°C for 5 hours. Next, the reaction is carried out according to the method according to JIS K 7301 until the content of the isocyanate group becomes 0.1 mass % or less. Then, 0.1 g of hydroquinone monomethyl ether as a polymerization inhibitor is added to the aforementioned flask to obtain the desired amine ester ( Meth)acrylate.

(Synthesis example 2)

In addition to using 299 g of polyethylene glycol tetramethylene glycol monomethacrylate (manufactured by NOF Corporation, trade name: BLEMMER 55PET-800) as the polyoxyalkylene derivative (A), and a dihydroxy compound (C) Except that 1 g of diethylene glycol was substituted for 300 g of polyethylene glycol tetramethylene glycol monomethacrylate, the same operation as in Synthesis Example 1 was performed to obtain the intended urethane (meth)acrylate.

(Comparative synthesis example 1)

In addition to using 300 g of polyethylene glycol monomethacrylate (manufactured by NOF Corporation, trade name: BLEMMER AE-200) as a polyoxyethylene derivative instead of polyethylene glycol tetramethylene glycol monomethacrylate Except for 300 g, the same operation as in Synthesis Example 1 was performed to obtain the intended amine ester (meth)acrylate.

(Preparation of photocurable resin composition)

(Example 1)

Mix 200 g of methyl ethyl ketone as a solvent, 100 g of urethane (meth)acrylate in Synthesis Example 1, 3 g of photopolymerization initiator ("IRGACURE 907" manufactured by BASF), and (meth)acrylic polymer Polymer 1 (copolymer of methacrylic acid, cyclohexyl methacrylate and methyl methacrylate), relative to the monomer components forming polymer 1 (i.e. methacrylic acid, cyclohexyl methacrylate and methyl methacrylate) The total amount of methyl acrylate), the amount of methacrylic acid is 20% by mass, the amount of cyclohexyl methacrylate is 50% by mass, the amount of methyl methacrylate is 30% by mass, the acid value of polymer 1 is 130 mgKOH/g, The weight average molecular weight of polymer 1 was 30,000)100g, and a photocurable resin composition was prepared.

(Example 2)

Except using 100 g of urethane (meth)acrylate in Synthesis Example 2 instead of 100 g of urethane (meth)acrylate in Synthesis Example 1, the same operation as in Example 1 was performed to obtain a photocurable resin composition. .

(Example 3)

In addition to using 99 g of urethane (meth)acrylate in Synthesis Example 1 and polyethylene glycol/tetramethylene glycol monomethacrylate (trade name, manufactured by NOF Corporation) as the polyoxyalkylene derivative (A) : BLEMMER 55PET-800)1g was used instead of 100g of urethane (meth)acrylate in Synthesis Example 1, and the same operation as Example 1 was performed to obtain a photocurable resin composition.

(Example 4)

In addition to using 95 g of urethane (meth)acrylate in Synthesis Example 1 and polyethylene glycol/tetramethylene glycol monomethacrylate (trade name, manufactured by NOF Co., Ltd.) as the polyoxyalkylene derivative (A) : BLEMMER 55PET-800) 5g was used instead of 100g of urethane (meth)acrylate in Synthesis Example 1, and the same operation as Example 1 was performed to obtain a photocurable resin composition.

(Example 5)

In addition to using 97.5 g of urethane (meth)acrylate in Synthesis Example 2 and polyethylene glycol/tetramethylene glycol monomethacrylate (manufactured by NOF Corporation, a commercial product) as the polyoxyalkylene derivative (A) Name: BLEMMER 55PET-800) 2.5g was used instead of 100g of urethane (meth)acrylate in Synthesis Example 1, and the same operation as Example 1 was performed to obtain a photocurable resin composition.

(Comparative example 1)

In addition to using 50 g of the urethane (meth)acrylate obtained in Synthesis Example 1 and polyethylene glycol/tetramethylene glycol monomethacrylate (manufactured by NOF Corporation, a commercial product) as the polyoxyalkylene derivative (A) Name: BLEMMER 55PET-800) 50g was substituted for 100g of urethane (meth)acrylate in Synthesis Example 1, and the same operation as Example 1 was performed to obtain a photocurable resin composition.

(Comparative example 2)

Except using 100 g of urethane (meth)acrylate in Comparative Synthesis Example 1 instead of 100 g of urethane (meth)acrylate in Synthesis Example 1, the same operation as in Example 1 was performed to obtain a photocurable resin composition. things.

(Comparative example 3)

Except that 100 g of trimethylolpropane triacrylate was used instead of 100 g of urethane (meth)acrylate in Synthesis Example 1, the same operation as in Example 1 was performed to obtain a photocurable resin composition.

(assessment)

(Assessment of volatility)

Use a rheometer to measure the viscosity of the photocurable resin composition at a temperature of 25°C and 1s ^-1 or a temperature of 25°C and 10s ^-1 , calculate the TI value from the following formula, and evaluate the thixotropy using the following standards. The results are presented in Tables 1 and 2.

TI value = viscosity of the photocurable resin composition at a temperature of 25°C and a shearing speed of 1s ^-1 / viscosity of a photocurable resin composition at a temperature of 25°C and a shearing speed of 10s ^-1

◎: TI value is 1.5 or more.

○: The TI value is 1.1 or more and less than 1.5.

×: TI value is 1.0 or more and less than 1.1.

(Assessment of Albinism)

8mm之筒之操作。在該試驗後以目視確認膜的外觀，用以下基準評定白化。結果呈示於表1及2。 The photocurable resin composition is coated on a polyethylene terephthalate (PET) film ("A4100" manufactured by Toyobo Co., Ltd., film thickness: 50 μm), and dried on a hot plate at 120°C for 5 minutes to obtain a photocurable resin. membrane of the composition. The obtained film was repeatedly wound 10 times using a cylindrical mandrel bending tester (manufactured by BEVS).

Operation of 8mm tube. After this test, the appearance of the film was visually confirmed, and whitening was evaluated based on the following standards. The results are presented in Tables 1 and 2.

◎: There is no change in the appearance of the film after the test.

○: The film after the test is slightly whitened.

×: The film turned white after the test.

(Evaluation of residual film rate)

The photocurable resin composition was applied to a glass substrate, dried at 120° C., and the film thickness (initial film thickness) of the obtained coating film was measured. Then, the obtained coating film is irradiated with ultraviolet rays to prepare a cured film. The obtained cured film was immersed in a 0.4 mass% tetramethylammonium hydroxide aqueous solution for 60 seconds, washed with water and dried, and then the film thickness of the cured film (film thickness after immersion) was measured. The film thickness was measured at three points using the stylus method. The average value was used as the value of the initial film thickness or the film thickness after immersion. The remaining film rate was calculated from the following formula and evaluated based on the following standards. The results are presented in Tables 1 and 2.

Residual film rate (%) = film thickness after immersion ( μm )/initial film thickness ( μm )×100

◎: The film remaining rate is over 85%.

○: The residual film rate is more than 80% and less than 85%.

×: The remaining film rate does not reach 80%.

(Evaluation of film strength)

The photocurable resin composition was applied to the glass substrate and dried on a hot plate at 120° C. to prepare a coating film. Then, the obtained coating film is irradiated with ultraviolet rays to prepare a cured film. Peel off the cured film from the glass substrate and cut a test piece with a width of 10 mm and a length of 50 mm. A tensile test is performed using an Autograph (manufactured by Shimadzu Corporation: EZ-SX) at a tensile speed of 10 mm/min and the tensile strength is measured. Benchmark to evaluate film strength. The results are presented in Tables 1 and 2.

◎: Tensile strength is 5.0N/ ^mm2 or more.

○: The tensile strength is 3.0 N/mm ² or more and less than 5.0 N/mm ² .

×: The tensile strength does not reach 3.0 N/mm ² .

(Evaluation of softness)

The preparation and tensile test of the test piece were carried out in the same manner as for the evaluation of the film strength described above, the rupture extension was calculated from the following formula, and the flexibility was evaluated according to the following standards. The results are presented in Tables 1 and 2.

Breakage extension (%)=100×(LL ₀ )/L ₀

(In the formula, L ₀ is the punctuation distance, and L is the punctuation distance when rupture)

◎: The rupture extension is 10% or more.

○: The rupture extension is 5% or more and less than 10%.

×: The rupture extension is less than 5%.

[Table 1]

TMPTA: trimethylolpropane triacrylate

Polymer 1: Copolymer of methacrylic acid, cyclohexyl methacrylate and methyl methacrylate.

[Table 2]

TMPTA: trimethylolpropane triacrylate

Polymer 1: Copolymer of methacrylic acid, cyclohexyl methacrylate and methyl methacrylate.

From the evaluation results shown in Table 1 and Table 2, it can be seen that the photocurable resin compositions of Examples 1 to 5 have excellent thixotropy, and the cured films obtained therefrom have excellent residual film ratio, tensile strength, and rupture elongation. , and the performance of not whitening when bending.

In Comparative Example 1, the polyoxyalkylene derivative (A) was used in a large amount, so the tensile strength was insufficient. In Comparative Example 2, the urethane (meth)acrylate of Comparative Synthesis Example 1, which did not meet the necessary conditions of the present invention, was used instead of the urethane (meth)acrylate of the present invention, so the fracture extension was insufficient. In Comparative Example 3, trimethylolpropane triacrylate was used instead of the urethane (meth)acrylate of the present invention, so the fracture extension was insufficient.

(industrial availability)

The photocurable resin composition containing urethane (meth)acrylate of the present invention can be used for coating materials, photoresists, etc., and can be used for manufacturing three-dimensional shaped objects.

This application is based on Japanese Patent Application No. 2022-077261 filed in Japan, and this specification includes its entire content.

Claims (3)

An urethane (meth)acrylate containing 75 to 90 mass % of the polyoxyalkylene derivative (A) represented by the formula (1), 10 to 25 mass % of the polyisocyanate compound (B) represented by the formula (2), and one obtained by reacting 0 to 5% by mass of the dihydroxy compound (C) represented by formula (3),

(In the formula, R ¹ is a hydrogen atom or a methyl group, l, m and n represent the average degree of polymerization respectively, l is a number from 1 to 20, m is a number from 0 to 15, and n is a number from 1 to 10)

(In the formula, 3 R ² are each independently an alkylene group having 1 to 10 carbon atoms) HO-(R ³ O)pH (3) (In the formula, R ³ is an alkylene group having 2 to 4 carbon atoms, and p represents the average degree of polymerization and is a number from 1 to 5). A photocurable resin composition containing: 35 to 60 mass% of urethane (meth)acrylate as described in claim 1; 35 to 60% by mass of (meth)acrylic polymer with an acid value of 50 to 300 mgKOH/g; and Photopolymerization initiator 0.1 to 5% by mass. A photocurable resin composition containing: 30 to 50 mass% of urethane (meth)acrylate as described in claim 1; 0.01 to 10 mass% of polyoxyalkylene derivative (A) represented by formula (1); 40 to 60% by mass of (meth)acrylic polymer with an acid value of 50 to 300 mgKOH/g; and Photopolymerization initiator 0.1 to 5% by mass;

(In the formula, R ¹ is a hydrogen atom or a methyl group, l, m and n respectively represent the average degree of polymerization, l is a number from 1 to 20, m is a number from 0 to 15, and n is a number from 1 to 10).