Photocurable ink composition and application thereof

Abstract

The invention provides a photocuring ink composition and application thereof, and can be applied to the technical field of photocuring materials. Based on the total mass of the photocuring ink composition, the photocuring ink composition comprises the following components in percentage by mass: 0.5%-15% of a benzoyl formate photoinitiator; 8%-20% of an adhesive resin; 15%-70% of a polymerizable acrylate monomer or an oligomer thereof; and 1%-50% of a coloring component. The photocuring ink composition provided by the invention is good in photocuring property, excellent in solvent wiping resistance, low in mobility and small in odor, has a wide application prospect, and is particularly beneficial to popularization and application in the food packaging industry.

Description

TECHNICAL FIELD

[0001] The present disclosure relates to the technical field of light-cured materials, in particular to a light-cured ink composition and application thereof. BACKGROUND

[0002] UV offset ink is dried and cured by ultraviolet radiation, relying on the free radicals formed after the absorption of radiation by the photoinitiator, to initiate the polymerization, cross-linking and grafting reaction of monomers and oligomers, to form a cross-linked three-dimensional network structure of high molecular polymer. Due to the incomparable advantages of UV offset ink over traditional oil-based ink, it has attracted more and more attention in the printing industry and is widely used in many fields such as cigarette packaging, wine packaging, cosmetic packaging, pharmaceutical packaging, and adhesive label trademarks. In recent years, it has also begun to enter the food packaging industry. Food packaging is in direct contact with the human body, so it has higher environmental protection requirements, especially the toxicity and migration of the ink, which is a very important issue for users.

[0003] The photoinitiator used in UV offset ink usually has genetic toxicity and / or reproductive toxicity, and has a certain migration, so its use in food packaging materials and materials in direct contact with the human body will be limited. SUMMARY

[0004] In view of this, the present disclosure provides a light-cured ink composition and application thereof. The light-cured ink composition is safe, non-toxic and has low migration, which is conducive to popularization and application in the food packaging industry.

[0005] According to a first aspect of the present disclosure, a light-cured ink composition is provided, based on the total mass of the light-cured ink composition, the light-cured ink composition comprises the following components: 0.5%-15% of a benzoyl formate photoinitiator; 8%-20% of an adhesive resin; 15%-70% of a polymerizable acrylate monomer or oligomer thereof; 1%-50% of a coloring component; wherein the benzoyl formate photoinitiator is formed by reaction of a first compound having a structure shown in formula (I), a second compound having a structure shown in formula (II), and a third compound having a structure shown in formula (III);

[0006]

[0007] wherein A is selected from any one of a single bond, O, S, CR2R3; R2and R3are each independently selected from any one of hydrogen, C1-C8linear alkyl or C3-C8branched alkyl; R1and R1' are each independently selected from any one of C1-C4alkyl; R a selected from hydrogen, -OH, C1-C 80 alkyl, C1-C 80any one of the groups in which at least one CH2in the alkyl group is replaced by oxygen or a phenyl ring; R b any one of a linear alkylene group having 1 to 8 carbon atoms or a branched alkylene group having 3 to 8 carbon atoms; q is any one of an integer from 1 to 20; when q is greater than 2, a plurality of R b are the same or different; p is any one of an integer from 2 to 10; R4is any one of hydrogen, a linear alkyl group having 1 to 8 carbon atoms or a branched alkyl group having 3 to 8 carbon atoms; R5and R6are each independently any one of hydrogen, a linear alkyl group having 1 to 8 carbon atoms or a branched alkyl group having 3 to 8 carbon atoms. 1- C 10 a linear alkyl group having 1 to 8 carbon atoms or a branched alkyl group having 3 to 8 carbon atoms; R5and R6are each independently any one of hydrogen, a linear alkyl group having 1 to 8 carbon atoms or a branched alkyl group having 3 to 8 carbon atoms. 3- C 10 a linear alkyl group having 1 to 8 carbon atoms or a branched alkyl group having 3 to 8 carbon atoms; R5and R6are each independently any one of hydrogen, a linear alkyl group having 1 to 8 carbon atoms or a branched alkyl group having 3 to 8 carbon atoms. 10 a linear alkyl group having 1 to 8 carbon atoms or a branched alkyl group having 3 to 8 carbon atoms; R5and R6are each independently any one of hydrogen, a linear alkyl group having 1 to 8 carbon atoms or a branched alkyl group having 3 to 8 carbon atoms. 3- C 10 a linear alkyl group having 1 to 8 carbon atoms or a branched alkyl group having 3 to 8 carbon atoms; R5and R6are each independently any one of hydrogen, a linear alkyl group having 1 to 8 carbon atoms or a branched alkyl group having 3 to 8 carbon atoms.

[0008] The second aspect of the present disclosure provides the use of the above-mentioned photocurable ink composition in an ink, particularly in an ultraviolet photocurable ink.

[0009] The third aspect of the present disclosure provides a preparation method of a photocurable ink composition, comprising the following steps: mixing a benzoyl formate photoinitiator, a binding resin, a polymerizable acrylate monomer or an oligomer thereof, and a coloring component to obtain a photocurable ink.

[0010] The benzoyl formate photoinitiator provided by the embodiments of the present disclosure is safe, non-toxic and low in migration, and the photocurable ink composition composed of the benzoyl formate photoinitiator, the binding resin, the polymerizable acrylate monomer or the oligomer thereof, and the coloring component has good photocurability, good solvent wiping resistance, low migration, and small odor, and has a broad application prospect, and is particularly beneficial to popularization and application in the food packaging industry. DETAILED DESCRIPTION

[0011] Hereinafter, embodiments of the present disclosure will be described. It should be understood, however, that the description is merely exemplary and is not intended to limit the scope of the present disclosure. In the following detailed description, numerous specific details are set forth in order to provide a thorough understanding of the embodiments of the present disclosure. It will be apparent, however, that one or more embodiments can be practiced without these specific details. In addition, in the following description, descriptions of well-known structures and techniques have been omitted to avoid unnecessary obscuring the concept of the present disclosure.

[0012] The terms used herein are merely used to describe specific embodiments and are not intended to limit the present disclosure. The terms "include", "comprise" and the like as used herein indicate the presence of the stated features, steps, operations and / or components, but do not exclude the presence or addition of one or more other features, steps, operations or components.

[0013] All terms used herein, including technical and scientific terms, have the meanings commonly understood by one of ordinary skill in the art, unless otherwise defined. It should be noted that the use of any terms herein should not be interpreted to exclude any other terms having the same meanings.

[0014] In the case of using expressions such as "at least one of A, B, and C, etc.", it is generally to be interpreted as including one or more of the same unless otherwise specified. For example, "a system having at least one of A, B, and C" is to be interpreted as including a system having A alone, a system having B alone, a system having C alone, a system having both A and B, a system having both A and C, a system having both B and C, and / or a system having A, B, and C, etc.

[0015] In the present disclosure, "each independently" means that the subject thereof has multiple, which can be the same or different from each other.

[0016] In the present disclosure, for the expression of chemical elements, unless otherwise specified, it generally includes the concept of isotopes of the same chemical properties, for example, the expression of "hydrogen (H)" also includes the concept of 1H (protium or H), 2H (deuterium or D) of the same chemical properties; carbon (C) includes 12C, 13C, etc., and will not be repeated.

[0017] In the present disclosure, the expression of Ca~Cb represents the number of carbon atoms of the group, and unless otherwise specified, the number of carbon atoms generally does not include the number of carbon atoms of the substituent.

[0018] In the present disclosure, the term "alkyl" can include a branched or straight saturated aliphatic monovalent hydrocarbon group having a specified number of carbon atoms. For example, as examples of C1~C8alkyl, there are mentioned methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, t-butyl, pentyl, isopentyl, hexyl, heptyl, octyl, and various isomers thereof, and the like. As examples of C1~C80alkyl, there are mentioned methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, undecyl, dodecyl,..., octacontyl, and various isomers thereof, and the like.

[0019] In the present disclosure, the term "straight-chain alkyl" can include an alkyl group having a specified number of carbon atoms formed into a continuous unbranched long chain (actually zigzag, but no side chain) connected by a single bond. For example, as examples of C1~C8straight-chain alkyl, there are mentioned methyl, ethyl, n-propyl, n-butyl, pentyl, hexyl, heptyl, octyl, and the like.

[0020] In the present disclosure, the term "branched alkyl" can include an alkyl group having a specified number of carbon atoms in which branching is present in the carbon chain (i.e., a shorter carbon chain side group is attached to the main chain). For example, as examples of C1-C8 branched alkyl, there can be mentioned isopropyl, sec-butyl, isobutyl, t-butyl, isopentyl, sec-pentyl, t-pentyl, isohexyl, 2-methylpentyl, 3-methylpentyl, t-hexyl, isoheptyl, isooctyl, dimethylpentyl, methylethylpentyl, t-octyl, and the like.

[0021] In the present disclosure, the term "alkylene" can include a branched or straight-chain saturated aliphatic divalent hydrocarbon group having a specified number of carbon atoms (i.e., a group formed by removing two hydrogen atoms from a molecule, each of the two ends having one attachment point). For example, as examples of C1-C8 alkylene, there can be mentioned methylene; ethylene, 1,1-ethylene; 1,2-propylene, 1,3-propylene; 1,4-butylene, 2-methyl-1,3-propylene, 1,2-butylene, 3-methyl-1,2-propylene; 1,5-pentylene, and 2-methyl-1,4-butylene, 3-methyl-1,4-butylene, 2,2-dimethyl-1,3-propylene, and the like branched isomers; 1,6-hexylene, and various branched hexylene isomers substituted with methyl, ethyl, and the like; 1,7-heptylene, and various branched isomers; 1,8-octylene, and various divalent isomers containing methyl, ethyl, and the like branched chains, and the like.

[0022] In the present disclosure, the term "branched alkylene" can include a saturated aliphatic divalent hydrocarbon group having a specified number of carbon atoms in which branching is present in the carbon chain (i.e., a shorter carbon chain side group is attached to the main chain). For example, as examples of C1-C8 branched alkylene, there can be mentioned 1-methyl ethylene, 1,2-propylene, 1,2-butylene, 2-methyl-1,3-propylene, 3-methyl-1,2-propylene, 2-methyl-1,4-butylene, 3-methyl-1,4-butylene, 2,2-dimethyl-1,3-propylene, branched hexylene substituted with methyl, branched hexylene substituted with ethyl, various branched heptylene isomers, branched octylene isomers containing methyl or ethyl side chains, and the like.

[0023] In the present disclosure, the term "branched alkylene" can include a saturated aliphatic divalent hydrocarbon group having a specified number of carbon atoms in which branching is present in the carbon chain (i.e., a shorter carbon chain side group is attached to the main chain). For example, as examples of C1-C8 branched alkylene, there can be mentioned 1-methyl ethylene, 1,2-propylene, 1,2-butylene, 2-methyl-1,3-propylene, 3-methyl-1,2-propylene, 2-methyl-1,4-butylene, 3-methyl-1,4-butylene, 2,2-dimethyl-1,3-propylene, branched hexylene substituted with methyl, branched hexylene substituted with ethyl, various branched heptylene isomers, branched octylene isomers containing methyl or ethyl side chains, and the like.

[0024] In the present disclosure, the term "a group in which at least one CH2in an alkyl group is replaced with an oxygen atom or a benzene ring" can include a derivative group formed by replacing at least one methylene group in an alkyl group having a prescribed number of carbon atoms with an oxygen atom or a benzene ring. For example, as the group in which at least one CH2in a C1-C80 alkyl group is replaced with an oxygen atom or a benzene ring, there can be mentioned methoxy, ethoxy, propoxy, butoxy, dioxapentyl, trioxyoctyl, decaoxatritriacontyl, eicosa-oxapentacontyl, trioxaoctadecyl, methoxyethyl, ethoxypropyl, hexyloxydecyl, benzyl, phenethyl, phenpropyl, phenbutyl, phendecyl, phenicosyl, phenapentyl, methylphenethyl, ethylphenpropyl, phenoxyethyl, phenoxypropyl, methoxyphenethyl, phenoxyeicosyl, decaoxaphenapentyl, and the like.

[0025] Unless otherwise defined, all technical and scientific terms used in the present disclosure have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure belongs; the terminology used in the disclosure is for the purpose of describing particular embodiments only and is not intended to be limiting of the disclosure; the use of the terms "including," "comprising," or "having" and variations thereof in the specification and claims of this disclosure are intended to be inclusive of a non-exclusive inclusion. Unless otherwise specified, the terms used in the present disclosure have the same meanings as commonly understood by a person skilled in the art. Unless otherwise specified, the numerical values of the parameters mentioned in the present disclosure can be measured using various measurement methods commonly used in the art (for example, can be tested according to the methods given in the embodiments of the present disclosure).

[0026] In the related art, a UV offset ink is composed of an epoxy acryl resin, a polyurethane acryl resin, a polyester acryl resin, an acryl monomer, a photoinitiator, a filler, and an organic pigment.

[0027] The photoinitiator used in UV offset printing ink is usually 2-methyl-1-[4-(methylthio)phenyl]-2-(4-morpholinyl)-1-propanone (hereinafter referred to as 907) and 2-isopropylthioxanthone (hereinafter referred to as ITX) are mainly used in combination, and 2,2-dimethoxy-2-phenylphenylacetone (hereinafter referred to as 651) can be added to red and yellow ink; 2-benzyl-2-dimethylamino-1-(4-morpholinylphenyl) butanone (hereinafter referred to as 369) is mainly used in black ink, and ITX and 2,4-diethylthioxanthone (hereinafter referred to as DETX) are used in combination; 2,4,6-trimethylbenzoyl diphenyl phosphine oxide (hereinafter referred to as TPO) and phenyl bis(2,4,6-trimethylbenzoyl) phosphine oxide (hereinafter referred to as 819) are mainly used in white ink, and 1-hydroxycyclohexyl phenyl ketone (hereinafter referred to as 184) or methyl benzoylformate (hereinafter referred to as MBF) is used in combination. Sometimes in order to improve the surface curing rate, a small amount of 4-dimethylamino benzoic acid ethyl ester (hereinafter referred to as EDAB) or active amine is often added. And the initiators 907 and 369 are determined to have reproductive toxicity, ITX has genetic toxicity and reproductive toxicity, and TPO is assumed to have reproductive toxicity to humans. And these small molecule initiators have a certain migration, so the use on food packaging materials and materials directly contacting the human body will be limited.

[0028] It is found in the implementation of the present disclosure that the use of benzoyl formate compound as a photoinitiator can obtain a photocuring ink composition which is safe, non-toxic, low migration and has good printing performance.

[0029] In view of this, the embodiments of the present disclosure provide a photocuring ink composition, which comprises the following components: (a) a benzoyl formate photoinitiator; (b) an adhesive resin; (c) a polymerizable acrylate monomer or an oligomer thereof; (d) a coloring ingredient.

[0030] The benzoyl formate photoinitiator provided by the embodiments of the present disclosure is safe, non-toxic and low in migration, and the photocuring ink composition composed of the benzoyl formate photoinitiator, the adhesive resin, the polymerizable acrylate monomer or the oligomer thereof and the coloring ingredient has good photocuring performance, good solvent wiping resistance, low migration and little odor, and has a wide application prospect, especially is beneficial to popularization and application in the food packaging industry.

[0031] (a) benzoyl formate photoinitiator

[0032] The benzoyl formate photoinitiator can be prepared by reaction of a first compound having a structure shown in formula (I), a second compound having a structure shown in formula (II) and a third compound having a structure shown in formula (III).

[0033]

[0034] wherein A is selected from any one of a single bond, O, S, CR2R3; R2and R3are each independently selected from any one of hydrogen, C1-C8linear alkyl, or C3-C8branched alkyl.

[0035] R1and R1' are each independently selected from any one of C1-C4alkyl.

[0036] R a selected from any one of hydrogen, -OH, C1-C 80 alkyl, C1-C 80 alkyl, C1-C

[0037] R b selected from any one of C1-C8linear alkylene or C3-C8branched alkylene.

[0038] q is selected from any one of an integer from 1 to 20; when q is greater than 2, the multiple R b are the same or different. Illustratively, q can be selected from 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13, 14, 15, 16, 17, 18, 19, or 20.

[0039] p is selected from any one of an integer from 2 to 10. Illustratively, p can be selected from 2, 3, 4, 5, 6, 7, 8, 9, or 10.

[0040] R4is selected from any one of hydrogen, C 1- C 10 linear alkyl, or C 3- C 10 branched alkyl.

[0041] R5and R6are each independently selected from any one of hydrogen, C1-C 10 linear alkyl, or C 3- C 10 branched alkyl, either alone or connected to each other to form a ring.

[0042] In some embodiments of the present disclosure, in the second compound, A can preferably be O or S.

[0043] In some embodiments of the present disclosure, in the second compound, R a may preferably be hydrogen, -OH, C1-C6alkyl, C1-C 11 alkyl, C1-C

[0044] In particular, R a may be selected from any one of H, -OH, , 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 、 .

[0045] In some embodiments of the present disclosure, R b may be selected from any one of -CH2-, -CH2CH2-, -CH2CH2CH2-, -CH2CH2CH2CH2-, -CH(CH3)-CH2-, -CH2-CH(CH3)-CH2-.

[0046] Optionally, the second compound can be selected from any one of polyethylene glycol, polypropylene glycol, 、 wherein x, y, z are each independently selected from an integer from 1 to 10, the sum of x, y, z is from 3 to 12, preferably, the sum of x, y, z can be from 6 to 12. Exemplarily, x, y, z can be each independently selected from 1, 2, 3, 4, 5, 6, 7, 8, 9, or 10. The sum of x, y, z can be 3, 4, 5, 6, 7, 8, 9, 10, 11, or 12.

[0047] In some embodiments of the present disclosure, the third compound can be selected from any one of the following compounds: 、 、 、 、 、 、 .

[0048] In some embodiments of the present disclosure, the number average molecular weight of the benzoyl formate photoinitiator can be 500-50000. Illustratively, the number average molecular weight of the benzoyl formate photoinitiator can be 500, 600, 800, 1000, 1200, 1500, 1800, 2000, 2200, 2500, 2800, 3000, 3200, 3500, 3800, 4000, 5000, 6000, 8000, 10000, 12000, 15000, 17000, 20000, 22000, 25000, 28000, 30000, 32000, 35000, 38000, 40000, 42000, 45000, 48000, 50000, or a range between any two of the above values.

[0049] In the present disclosure, different compounds or mixtures of benzoyl formate photoinitiators with different structures can be obtained according to the ratio of the first compound, the second compound and the third compound, and the raw materials.

[0050] The preparation method of the above-mentioned benzoyl formate photoinitiator of the present disclosure refers to the preparation method of the photoinitiator described in Chinese invention patent 202510123912.6 application, which will not be repeated here.

[0051] The mass content of the benzoyl formate photoinitiator can be 0.5%-15%, preferably 3%-15%, based on the total mass of the photocurable ink composition. Illustratively, the mass content of the benzoyl formate photoinitiator can be 0.5%, 1%, 1.5%, 2%, 2.5%, 3%, 3.5%, 4%, 5%, 6%, 7%, 7.5%, 8%, 8.5%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, or a range between any two of the above values.

[0052] In the present disclosure, in addition to the above benzoyl formate photoinitiator, it is also possible to appropriately use a general photopolymerization initiator in view of the kind of ultraviolet light source used, the irradiation intensity of the ultraviolet light source, the cumulative light amount of the ultraviolet light irradiation, color, printed film thickness, hygienic properties, and the like, without impairing the effects of the present disclosure. For example, compounds such as 2,2-dimethoxy-1,2-diphenyl ethan-1-one, 1-hydroxy-cyclohexyl-phenyl-ketone, 2-hydroxy-2-methyl-1-phenyl-propan-1-one, 1-[4-2-hydroxyethoxy)-phenyl]-2-hydroxy-2-methyl-1-propan-1-one, 2-hydroxy-1-{4-[4-(2-hydroxy-2-methyl-propionyl)-benzyl]phenyl}-2-methyl-propan-1-one, phenyl glyoxylic acid methyl ester, hydroxyphenyl acetic acid, a mixture of 2-[2-oxo-2-phenylacetyloxyethoxy]ethyl ester and 2-(2-hydroxyethoxy)ethyl ester of hydroxyphenyl acetic acid, 1,2-octanedione, 1-[4-(phenylthio)-, 2-(o-benzoyl oxime)], ethanone, 1-[9-ethyl-6-(2-methylbenzoyl)-9H-carbazol-3-yl]-, 1-(o-acetyl oxime), 2-(dimethylamino)-2-[(4-methylphenyl)methyl]-1-[4-(4-morpholino)phenyl]-1-butanone, and the like can be mentioned.

[0053] Further, acyloxyphosphine compounds such as bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, bis(2,6-dimethoxybenzoyl)-2,4,4-trimethyl-pentylphosphine oxide, and the like can be mentioned.

[0054] Further, thioxanthone compounds such as 2,4-diethylthioxanthone, 2,4-dimethylthioxanthone, 2,4-dichlorothioxanthone, 2-chlorothioxanthone, 1-chloro-4-propoxythioxanthone, 2-hydroxy-3-(3,4-dimethyl-9-oxo-9H thioxanthen-2-yloxy-N,N,N-trimethyl-1-propanaminium hydrochloride, and the like can be mentioned.

[0055] Further, 4,4'-dialkylaminobenzophenones such as 4,4'-bis-(dimethylamino)benzophenone, 4,4'-bis-(diethylamino)benzophenone, benzophenone compounds such as 4-benzoyl-4'-methyl diphenyl sulfide, and the like can be mentioned.

[0056] In addition to the above, examples include benzophenone, 4-methyl-benzophenone, 2,4,6-trimethylbenzophenone, 2,3,4-trimethylbenzophenone, 4-phenylbenzophenone, 3,3'-dimethyl-4-methoxybenzophenone, 4-(1,3-acryloyl-1,4,7,10,13-pentaoxytridecyl)benzophenone, methyl-o-benzoylbenzoate, [4-(methylphenylthio)phenyl]phenylmethanone, diethoxyphenylacetophenone, dibutoxyphenylacetophenone, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzoin n-butyl ether, and the like.

[0057] In the present disclosure, the mass content of the benzoyl formate photoinitiator and other photoinitiators together can be 0.5% to 15%, preferably 1% to 10%, based on the total mass of the photocurable ink composition. Illustratively, the mass content of the benzoyl formate photoinitiator and other photoinitiators together can be 0.5%, 1%, 2%, 3%, 4%, 5%, 6%, 7%, 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, or a range between any two of the above values, based on the total mass of the photocurable ink composition.

[0058] In addition, in order to improve light efficiency or match a light source of a specific wavelength, a sensitizer can also be added. Suitable sensitizers can be anthracene, coumarin, or pyrazoline sensitizers, and specifically, preferred sensitizers can be the anthracene sensitizers described in Chinese patent application Nos. 201510355839.1, 201510355364.6, and 201510353754.X, which are not described here again.

[0059] (b) Adhesive resin

[0060] In the present disclosure, the adhesive resin can refer to a resin having suitable pigment affinity and dispersibility, and having the rheological properties required for printing ink. The present disclosure does not particularly limit the adhesive resin, as long as the purpose of the present disclosure can be achieved. Illustratively, the adhesive resin can be various adhesive resins known and commonly used. Optionally, the adhesive resin includes at least one non-reactive resin. The adhesive resin can also include a compound having a polymerizable group.

[0061] For example, as the non-reactive resin, there can be mentioned a diallyl phthalate resin obtained by polymerizing diallyl phthalate and / or diallyl isophthalate and / or diallyl terephthalate, an epoxy resin, a polyurethane resin, a polyester resin, a petroleum resin, a rosin ester resin, a poly(meth)acrylate, a cellulose derivative, a vinyl chloride-vinyl acetate copolymer, a polyamide resin, a polyvinyl acetal resin, a butadiene-acrylonitrile copolymer, and the like. In addition, an epoxy acrylate compound having at least one or more polymerizable groups in the molecule, an urethane acrylate compound, a polyester acrylate compound, and the like can also be used, and these adhesive resins can be used alone or in combination of any of them.

[0062] In the case where the benzoyl formate photoinitiator is used in combination with the diallyl phthalate resin, the flowability of the ink can be improved in addition to the improvement in the curability of the active energy ray-curable ink, and the occurrence of defects in the printability such as cracking of the container on the printer and poor transfer between the ink rollers can be suppressed.

[0063] In the present disclosure, the content of the adhesive resin can be 8% to 20%, preferably 10% to 17%, based on the total mass of the photocurable ink composition. Illustratively, the content of the adhesive resin can be 8%, 9%, 10%, 11%, 12%, 13%, 14%, 15%, 16%, 17%, 18%, 19%, 20%, or a range between any two of these values, based on the total mass of the photocurable ink composition.

[0064] (c) a polymerizable acrylate monomer or oligomer

[0065] The polymerizable acrylate monomer or oligomer is not particularly limited in the present disclosure as long as the object of the present disclosure can be achieved. For example, the polymerizable acrylate monomer or oligomer can be a monomer and / or an oligomer used in the field of UV curing technology. A polymerizable monomer and / or an oligomer having a (meth)acryloyl group as a reactive group is particularly preferred.

[0066] The number of reactive groups and the molecular weight of the polymerizable acrylate monomer or oligomer are also not particularly limited in the present disclosure. The higher the number of reactive groups, the higher the reactivity, but the higher the viscosity or crystallinity. In addition, the higher the molecular weight, the higher the viscosity. Therefore, they can be appropriately used in combination depending on the desired properties. For example, in the case of curing by low-energy irradiation with a UV-LED or the like, a polymerizable acrylate monomer having 3 or more functional groups with high reactivity can be selected; in order to obtain necessary properties such as adhesion to a print substrate, softness of a film, and the like depending on the use, a polymerizable acrylate monomer having a mono-functional group and / or a multi-functional group can be appropriately used alone or in combination. The polymerizable acrylate monomer can include at least one of a mono-functional group (meth)acrylate and a multi-functional group (meth)acrylate.

[0067] As the monofunctional (meth)acrylate, for example, ethyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, nonyl (meth)acrylate, lauryl (meth)acrylate, tridecyl (meth)acrylate, cetyl (meth)acrylate, stearyl (meth)acrylate, isoamyl (meth)acrylate, isodecyl (meth)acrylate, isostearyl (meth)acrylate, cyclohexyl (meth)acrylate, benzyl (meth)acrylate, methoxyethyl (meth)acrylate, butoxyethyl (meth)acrylate, phenoxyethyl (meth)acrylate, phenoxydiethylene glycol (meth)acrylate, nonylphenoxyethyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, glycidyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxy-3-phenoxypropyl (meth)acrylate, 3-chloro-2-hydroxypropyl (meth)acrylate, diethylaminoethyl (meth)acrylate, nonylphenoxyethyl tetrahydrofurfuryl (meth)acrylate, caprolactone-modified tetrahydrofurfuryl (meth)acrylate, isobornyl (meth)acrylate, dicyclopentyl (meth)acrylate, dicyclopentenyloxyethyl (meth)acrylate, and the like can be given.

[0068] As the 2 or more functional (meth)acrylate, there are mentioned, for example, di(meth)acrylates of dihydric alcohols such as 1,4-butanediol di(meth)acrylate, 3-methyl-1,5-pentanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 2-methyl-1,8-octanediol di(meth)acrylate, 2-butyl-2-ethyl-1,3-propanediol di(meth)acrylate, tricyclodecane dimethanol di(meth)acrylate, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, di(meth)acrylate of tris(2-hydroxyethyl)isocyanurate, di(meth)acrylate of diol obtained by adding 4 or more moles of ethylene oxide or propylene oxide to 1 mole of neopentyl glycol, di(meth)acrylate of diol obtained by adding 2 moles of ethylene oxide or propylene oxide to 1 mole of bisphenol A, trimethylolpropane tri(meth)acrylate, glycerol tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, poly(meth)acrylate of di- or more polyhydric alcohol such as pentaerythritol, triol tri(meth)acrylate obtained by adding 3 or more moles of ethylene oxide or propylene oxide to 1 mole of glycerol, di(meth)acrylate or tri(meth)acrylate of triol obtained by adding 3 or more moles of ethylene oxide or propylene oxide to 1 mole of trimethylolpropane, di(meth)acrylate of diol obtained by adding 4 or more moles of ethylene oxide or propylene oxide to 1 mole of bisphenol A, and poly(meth)acrylate of polyoxyalkylene polyol.

[0069] As the polymerizable oligomer, there are mentioned amine-modified polyether acrylate, amine-modified epoxy acrylate, amine-modified aliphatic acrylate, amine-modified polyester acrylate, amino (meth)acrylate, thiol-modified polyester acrylate, thiol (meth)acrylate, polyester (meth)acrylate, polyether (meth)acrylate, polyolefin (meth)acrylate, polystyrene (meth)acrylate, epoxy (meth)acrylate, urethane (meth)acrylate, and the like.

[0070] As the above-mentioned polymerizable acrylate monomer and or oligomer, a (meth)acrylate having 4 or more functions is greatly helpful for the improvement of the curing property, strength in the printing application to paper such as wood-free paper, coated paper, copper plate paper, molded paper, tissue paper, thick paper, and thus is preferably used. It is preferable to use in the range of 15% to 70% by mass relative to the total amount of the photocurable ink composition. On the other hand, in the printing application to plastic, as the crosslinking density of the cured coating film increases, the adhesion of the substrate to the cured coating film decreases, and thus it is necessary to appropriately reduce the content of the (meth)acrylate having 4 or more functions. At this time, the content of the (meth)acrylate having 4 or more functions is preferably used in the range of 0 to 50% by mass based on the total mass of the photocurable ink composition.

[0071] The content of the polymerizable acrylate monomer or oligomer thereof is 15% to 70% by mass, preferably 30% to 60% by mass, based on the total mass of the photocurable ink composition. Illustratively, the content of the polymerizable acrylate monomer or oligomer thereof is 15%, 20%, 25%, 30%, 35%, 40%, 45%, 50%, 55%, 60%, 65%, 70% or more by mass, or a range between any two of these values, based on the total mass of the photocurable ink composition.

[0072] (d) Colorant

[0073] The photocurable ink composition in the present disclosure can be added with a colorant as needed. The colorant in the present disclosure is not particularly limited as long as the object of the present disclosure can be achieved. The colorant can be an ingredient added in order to impart color strength, hiding power, and the like to the ink composition, and color pigments, white pigments, metal powders, and the like can be exemplified. As such a colorant, conventional organic and / or inorganic pigments used in ink compositions are not particularly limited. Note that the photocurable ink composition in the present disclosure is preferably used for paint applications and the like when it does not contain a colorant.

[0074] The organic pigment can use a publicly known organic pigment according to the target hue, and for example, azo pigments (azo lakes, insoluble azo pigments, condensed azo pigments, chelate azo pigments, and the like), polycyclic pigments (phthalocyanine pigments, perylene pigments, perinone pigments, anthraquinone pigments, quinacridone pigments, dioxazine pigments, thioindigo pigments, isoindolinone pigments, quinophthalone pigments, and the like), dye chelates (basic dye type chelates, acid dye type chelates, and the like), nitro pigments, nitroso pigments, aniline black, and the like can be used.

[0075] As the inorganic pigment, inorganic coloring pigments such as titanium oxide, graphite, zinc white, and the like, inorganic body pigments such as calcium carbonate powder, gypsum, clay, silica powder, diatomaceous earth, talc, kaolin, alumina white, barium sulfate, aluminum stearate, magnesium carbonate, heavy spar powder, polishing powder, and the like, silicone, glass beads, and the like can be exemplified.

[0076] The content of the coloring component is not particularly limited in the present disclosure, as long as the object of the present disclosure can be achieved. For example, the mass content of the coloring component is 1 to 50%, preferably 10 to 45%, based on the total mass of the photocurable ink composition. Illustratively, the mass content of the coloring component is 1%, 3%, 5%, 8%, 10%, 15%, 20%, 22%, 25%, 28%, 30%, 35%, 40%, 45%, 50% or any range between any two of the numerical values, based on the total mass of the photocurable ink composition. It should be noted that other coloring components of other colors can also be used together as a complementary color when preparing the colored photocurable ink composition, or other ink compositions of other colors can also be added.

[0077] The photocurable ink composition of the present disclosure can further add other components (e) as needed, in addition to the above-mentioned components.

[0078] As the component, fillers, polymerization inhibitors, dispersants, co-dispersants, leveling agents, defoaming agents, salts such as phosphates, carnauba wax, wood wax, lanolin, montan wax, paraffin wax, microcrystalline wax, and natural waxes; Fischer-Tropsch wax, polyethylene wax, polypropylene wax, polytetrafluoroethylene wax, polyamide wax, silicone compounds, and silicon gas can be listed.

[0079] As the filler, inorganic or organic, powdery, flaky or fibrous materials are included. Examples of inorganic fillers include mica, glass or silica, calcium carbonate, barium sulfate, talc, glass or silica foam, zirconium silicate, iron oxide, glass fiber, asbestos, diatomaceous earth, dolomite, powdered metal, titanium oxide, pulp powder, kaolin, modified kaolin, hydrous kaolin metal filler, ceramic and composite materials. Examples of organic fillers include polymeric compounds, thermoplastic, core shell, aramid, Kevlar, nylon, crosslinked polystyrene, crosslinked poly(methyl methacrylate), polystyrene or polypropylene, crosslinked polyethylene powder, crosslinked phenol resin powder, crosslinked urea resin powder, crosslinked melamine resin powder, crosslinked polyester resin powder and crosslinked epoxy resin powder. Optionally, both inorganic and organic fillers can be surface treated with various compound-coupling agents. Examples include methacrylpropyltrimethoxysilane, β-(3,4-epoxycyclohexyl)ethyltrimethoxysilane, γ-glycidylpropyltrimethoxysilane and methyltriethoxysilane. Mixtures of inorganic and organic fillers can also be used. Other examples of preferred fillers are microcrystalline silica, crystalline silica, amorphous silica, basic aluminum silicate, feldspar, alumina, aluminum hydroxide, glass powder, alumina trihydrate, surface treated alumina trihydrate, and aluminum silicate. Each of the preferred fillers is commercially available. The most preferred fillers are inorganic fillers such as silica, Imsil, Novasite, amorphous silica, feldspar, and alumina trihydrate. These fillers are preferably transparent to UV light, have a low tendency to refract or reflect incident light, and provide good dimensional stability and heat resistance. Nanofillers such as exfoliated clay (nanoclay), nanosilica, aluminum borate whisker, nanobarium sulfate, silica nanoparticles dispersed in UV-curable monomers, alumina nanoparticles dispersed in UV-curable monomers can also be used.

[0080] As the polymerization inhibitor, the following are preferably listed: phenolic compounds such as butylated hydroxytoluene, tocopherol acetate, nitrosamine, benzotriazole, hindered amine, p-methoxyphenol (hereinafter referred to as MEHQ), and the like, and more preferably butylated hydroxytoluene. By adding a polymerization inhibitor to the ink composition, the progress of the polymerization reaction during storage and the tackiness of the ink composition can be inhibited. The mass content of the polymerization inhibitor can be 0.01% to 1% based on the total mass of the photocurable ink composition.

[0081] The dispersant is used to disperse the coloring ingredients and the filler pigments contained in the ink composition in a good state. Various substances of the above-described dispersant are commercially available, and the following can be listed: the DISPERBYK (trade name) series manufactured by Big Chemie Japan Co., Ltd., and the like.

[0082] Another aspect of the present disclosure provides a method for preparing the above-mentioned photocurable ink composition, comprising: mixing the above-mentioned benzoyl formate photoinitiator, adhesive resin, polymerizable acrylate monomer or oligomer thereof, and coloring ingredient to obtain the photocurable ink composition.

[0083] The selection and mass content of the benzoyl formate photoinitiator, adhesive resin, polymerizable acrylate monomer or oligomer thereof, and coloring ingredient can be set according to the above-mentioned photocurable ink composition, which will not be repeated here.

[0084] Another aspect of the present disclosure provides the use of the above-mentioned photocurable ink composition in ink, especially in ultraviolet photocurable ink.

[0085] The photocurable ink composition of the present disclosure can be made into a cured film by irradiating active energy rays after printing on a printing substrate. The active energy rays can be ionizing radiation such as ultraviolet rays, electron beams, alpha rays, beta rays, gamma rays, etc. Among them, from the viewpoint of curing property and convenience, ultraviolet rays (UV) are particularly preferred.

[0086] As the above-mentioned printing substrate, paper substrates for packaging of food packaging materials, catalogs, posters, flyers, CD sleeves, direct mail, brochures, cosmetics, beverages, pharmaceuticals, toys, equipment, etc.; films for various food packaging materials such as polypropylene films, polyethylene terephthalate (PET) films, etc.; aluminum foil; synthetic paper; and other various substrates that have been used as printing substrates can be listed.

[0087] The present disclosure is not particularly limited to the use of the photocurable ink composition as long as the purpose of the present disclosure can be achieved. For example, the photocurable ink composition can be applied by means of offset, waterless, gravure, flexographic, screen, inkjet, coating, etc.

[0088] Specifically, in the present disclosure, the types of ink include but are not limited to screen printing ink, decorative ink, offset ink, letterpress ink, flexographic ink, gravure ink, pad printing ink, inkjet ink, etc.

[0089] Another aspect of the present disclosure provides a method for making a photocurable ink, comprising the following steps: mixing a benzoyl formate photoinitiator, an adhesive resin, a polymerizable acrylate monomer or oligomer thereof, a coloring ingredient, and other additives to obtain the photocurable ink.

[0090] In some embodiments of the present application, the adhesive resin, at least part of the polymerizable acrylate monomer or oligomer thereof, and the polymerization inhibitor can be mixed to obtain a varnish; the benzoyl formate photoinitiator, the coloring ingredient, and the remaining polymerizable acrylate monomer or oligomer thereof can be mixed with the varnish to obtain a photocuring ink. That is, the adhesive resin, the polymerizable acrylate monomer or oligomer thereof can be mixed to obtain a varnish; the benzoyl formate photoinitiator, the coloring ingredient, and the remaining polymerizable acrylate monomer or oligomer thereof can be mixed with the varnish to obtain a photocuring ink. The adhesive resin, part of the polymerizable acrylate monomer or oligomer thereof can be mixed to obtain a varnish; the benzoyl formate photoinitiator, the coloring ingredient, and the remaining part of the polymerizable acrylate monomer or oligomer thereof can be mixed with the varnish to obtain a photocuring ink.

[0091] Exemplarily, the method for preparing the photocuring ink can include the following steps 1-4.

[0092] Step 1: The adhesive resin, the polymerizable acrylate monomer or oligomer thereof, and the polymerization inhibitor are weighed and mixed in proportion.

[0093] Step 2: The mixture of step 1 is dispersed at high speed for 2-4 hours to prepare a varnish.

[0094] Step 3: The above varnish, the polymerizable acrylate monomer or oligomer thereof, the filler, and the photoinitiator are further mixed in proportion.

[0095] Step 4: The mixture in step 3 is mixed by using a three-roll mill, and the grinding time is 30-60 minutes to prepare a photocuring ink composition.

[0096] Since the present disclosure adopts the safe, non-toxic, and low-migration benzoyl formate photoinitiator, the photocuring ink composition composed of the adhesive resin, the polymerizable acrylate monomer or oligomer thereof, and the coloring ingredient has good photocuring property, good solvent wiping resistance, low migration, and small odor, and the present disclosure also provides the application of the above photocuring ink composition in the field of food packaging.

[0097] Hereinafter, the present disclosure will be described more specifically through examples, but the present disclosure is not limited to the following examples.

[0098] Unless otherwise specified, the raw materials used in the examples are conventional materials in the art, which can be purchased through commercial channels. Unless otherwise specified, "%" means "mass%", and "parts" means mass parts.

[0099] Example 1

[0100] The present embodiment provides a photocuring ink composition, which includes a benzoyl formate photoinitiator, an adhesive resin, a polymerizable acrylate monomer or oligomer thereof, and a coloring ingredient.

[0101] The method for preparing the photocurable ink composition is as follows:

[0102] (1) Preparation of benzoyl formate photoinitiator

[0103] Into a 250 mL single-neck flask was added 35 g of the first compound shown in (I-1) below, 60 g of the second compound polyethylene glycol-300 shown in (II-1) below, and 1 g of potassium acetate. After mixing, the system was warmed up, and when the external temperature reached 90°C, stirring was started. The system was vacuumed, and when the pressure dropped to -0.095 MPa, the external temperature was maintained at 90°C and stirring was continued for 4 h. After the temperature was maintained, the system was broken by nitrogen, and 10 g of the third compound 4-diethylaminobenzoic acid ethyl ester shown in (III-1) below was added. The vacuum degree of the system was further increased to 200-300 Pa, and the external temperature was maintained at 90°C and stirring was continued. The reaction was tracked by GPC, and when the weight average molecular weight of the product was >1000, the reaction was stopped. The system was cooled to room temperature, 1 g of activated carbon was added to the reaction liquid and stirred for 2 h, and then filtered to obtain 95.0 g of a viscous yellow liquid (compound 1) with a weight average molecular weight of 2246.

[0104]

[0105] (2) Preparation of varnish

[0106] A varnish was prepared by high-speed dispersing 25 parts by mass of polydiallyl phthalate (produced by Changzhou Qiangli New Material Co., Ltd.), 70 parts by mass of ditrimethylolpropane tetraacrylate (Sartomer), 5 parts by mass of trihydroxypropane triacrylate (Sartomer), and 0.1 part by mass of MEHQ for 3 h. The varnish was used to prepare the various ink compositions described below.

[0107] (3) Preparation of photocurable ink composition

[0108] The colorant, the above-described varnish, trimethylolpropane triacrylate (Sartomer, abbreviated as TMPTA), the filler, the photoinitiator, and the additive were mixed in the amounts described in Tables 2 and 3, and then mixed by using a three-roll mill to prepare a photocurable ink composition. Note that the values of the amounts of each component shown in Tables 2 and 3 are parts by mass.

[0109] Example 2

[0110] The present example provides a photocurable ink composition including a benzoyl formate photoinitiator, an adhesive resin, a polymerizable acrylate monomer or an oligomer thereof, and a coloring component.

[0111] The method for preparing the photocurable ink composition was the same as in Example 1, except that the benzoyl formate photoinitiator was prepared as follows:

[0112] In a 250mL single-neck flask, 34g of the first compound shown in (I-2) below, 60g of the second compound shown in (II-2) below, polypropylene glycol-300 (2b), 1g of potassium acetate were added, and the system was uniformly mixed and then started to be heated. When the external temperature rose to 90℃, stirring was started, the system was vacuumized, and when the pressure dropped to -0.095MPa, the external temperature was kept at 90℃ and stirring was continued for 4h. After the temperature holding was completed, the system was broken by nitrogen, 9.5g of the third compound shown in (III-2) below, 4-dimethylaminobenzoic acid ethyl ester (2c), was added, the vacuum degree of the system was further increased to 200-300Pa, the external temperature was kept at 90℃ and stirring was continued, and the reaction was tracked by GPC. When the weight average molecular weight of the product was greater than 1000, the reaction was stopped, 1g of activated carbon was added to the reaction liquid and stirred for 2h, and then filtration was performed to obtain 93.0g of a yellow viscous liquid (compound 2) with a weight average molecular weight of 2136.

[0113]

[0114] Example 3

[0115] The present example provides a photocurable ink composition, which includes a benzoyl formate photoinitiator, an adhesive resin, a polymerizable acrylate monomer or oligomer thereof, and a coloring component.

[0116] The preparation method of the photocurable ink composition is as described in Example 1, except that the preparation method of the benzoyl formate photoinitiator is as follows:

[0117] In a 250mL single-neck flask, 20g of the first compound shown in (I-3) below, 30.77g of the second compound shown in (II-3) below, TMP-9E0 (weight average molecular weight 530), 43.14g of the third compound shown in (III-3) below, and 1g of potassium acetate were added, and the system was uniformly mixed and then started to be heated. When the external temperature rose to 110℃, stirring was started, the system was vacuumized, and when the pressure dropped to -0.095MPa, the external temperature was kept at 90℃ and stirring was continued for 5.5h. The reaction was tracked by GPC, and when the weight average molecular weight of the product was greater than 1000, the reaction was stopped. The system was cooled to room temperature, 1g of activated carbon was added to the reaction liquid and stirred for 2h, and then filtration was performed to obtain 83.5g of a yellow viscous liquid (compound 3) with a weight average molecular weight of 2801.

[0118]

[0119] Examples 4-18

[0120] The present example provides a photocurable ink composition, which includes a benzoyl formate photoinitiator, an adhesive resin, a polymerizable acrylate monomer or oligomer thereof, and a coloring component.

[0121] The light-curable ink composition was prepared according to the method of Example 1, except that the photoinitiator added in the present comparative example was as shown in Table 3.

[0122] According to the synthesis method of Example 1, 2 or 3, different raw materials were changed to obtain benzoyl formate photoinitiators with different structures and molecular weights as shown in Table 1.

[0123] Comparative Examples 1-5

[0124] The present comparative example provides a light-curable ink composition comprising a photoinitiator, an adhesive resin, a polymerizable acrylate monomer or oligomer thereof, and a coloring component. The light-curable ink composition was prepared according to the method of Example 1, except that the photoinitiator added in the present comparative example was as shown in Table 3.

[0125] Table 1

[0126]

[0127]

[0128] Table 2

[0129]

[0130] Table 3

[0131]

[0132] Specifically, in Table 2 and Table 3, the components are as follows:

[0133] Pigment Red 254: diketopyrrolopyrrole DPP (Shanghai Jingyan Chemical)

[0134] PY13: azo-based organic pigment (Yuhong Pigment Co., Ltd.)

[0135] 15:3: Pigment Blue 15:3 (Hubei Zhonglong Kangsheng)

[0136] BK7: high-pigment carbon black (BASF)

[0137] Titanium white: titanium dioxide (Shanghai Jingyan Chemical)

[0138] 907: 2-methyl-1-[4-(methylthio)phenyl]-2-(4-morpholinyl)-1-propanone (Changzhou Qiangli Electronic New Materials Co., Ltd.)

[0139] EDB: ethyl p-N,N-dimethylaminobenzoate (Changzhou Qiangli Electronic New Materials Co., Ltd.)

[0140] DETX: 2,4-diethylthioxanthone (Changzhou Qiangli Electronic New Materials Co., Ltd.)

[0141] 369: 1-(4-morpholinophenyl)-2-(dimethylamine)-2-benzyl-1-butanone (Changzhou Qiangli Electronics New Material Co., Ltd.)

[0142] 4MPBZ: 4-phenylbenzophenone (Changzhou Qiangli Electronics New Material Co., Ltd.)

[0143] 1173: 2-hydroxy-2-methyl-1-phenyl-1-propanone (Changzhou Qiangli Electronics New Material Co., Ltd.)

[0144] TPO: trimethylbenzoyl-diphenylphosphine oxide (Changzhou Qiangli Electronics New Material Co., Ltd.)

[0145] ASA: polyethylene glycol di-(p-dimethylaminobenzoic acid) ester (Changzhou Qiangli Electronics New Material Co., Ltd.)

[0146] The ink composition prepared above is weighed 0.45 g using a color spreader (CIBA-NB900), applied on the color spreader rubber roller to perform ink homogenization, and a silver card paper with a size of 20 cm*5 cm is loaded to perform color spreading, and the ink is uniformly transferred to the silver card paper, and multiple color spreaders are prepared according to the test items, and then curing evaluation, solvent resistance evaluation, migration evaluation, and odor evaluation are performed. The test methods and equipment are as follows:

[0147] <Curing Evaluation>

[0148] The photocuring ink composition provided in each example and comparative example is exposed using a 385 nm LED (RW-LED-YT200S) exposure machine, and the energy meter is placed on the conveying belt, and the measured power is 5 W / cm 2 The above color spreader is subjected to ultraviolet irradiation on a 1 m conveying belt at a speed of 2.5 m / min, and after one pass, the surface dryness of the ink is evaluated by touch, and the grade is divided based on the following evaluation criteria:

[0149] 1st grade: surface oily, not cured;

[0150] 2nd grade: surface sticky, with curing tendency;

[0151] 3rd grade: surface basically dry, with heavy fingerprint when pressed;

[0152] 4th grade: surface basically dry, slightly astringent, with light fingerprint when pressed;

[0153] 5th grade: surface completely dry, smooth and no fingerprint.

[0154] <Solvent Resistance Evaluation>

[0155] The photocurable ink composition provided in each of the examples and comparative examples was exposed to light using a 385 nm LED (RW-LED-YT200S) exposure machine at a power of 5 W / cm 2 , and the above color development was subjected to 1000 mj of ultraviolet irradiation. The number of times of rubbing with a solvent-resistant wiper until the ink was rubbed off and the substrate began to show the underlying color was measured. The results were classified into the following levels based on the following evaluation criteria:

[0156] : > 200 times;

[0157] : 150 or more and less than 200 times;

[0158] : 100 or more and less than 150 times;

[0159] : < 100 times.

[0160] <Migration Evaluation>

[0161] The photocurable ink composition provided in each of the examples and comparative examples was exposed to light using a 385 nm LED (RW-LED-YT200S) exposure machine at a power of 5 W / cm 2 , and the above color development was subjected to 1000 mj of ultraviolet irradiation. A PP film of the same area as the cured ink was then overlaid on the cured ink, and the overlaid film was left to stand for 10 days at 25°C and 50% relative humidity under a load of 0.02 kg / cm 2 . Thereafter, the PP film was immersed in ethanol 100 ml at 60°C and 50% relative humidity for 10 days, and the resulting ethanol solution was analyzed using an Agilent LC-MS. The results were classified into the following levels based on the following evaluation criteria:

[0162] <Odor Evaluation>

[0163] The photocurable ink composition provided in each of the examples and comparative examples was exposed to light using a 385 nm LED (RW-LED-YT200S) exposure machine at a power of 5 W / cm 2 , and the above color development was subjected to 1000 mj of ultraviolet irradiation. The silver card paper with the cured ink was then cut into small pieces of 5 cm * 3 cm, and the pieces were inserted into plastic bottles, which were sealed and left to stand in an oven at 40°C for 2 h. The bottles were then taken out, and the size of the odor emitted immediately after opening the bottles was evaluated. The results were classified into the following levels based on the following evaluation criteria:

[0164] 1st: no odor;

[0165] 2: Taste;

[0166] 3: Pungent odor.

[0167] The relevant evaluation results are shown in Tables 4 and 5.

[0168] Table 4

[0169]

[0170] Table 5

[0171]

[0172] It can be seen from Tables 4 and 5 that the photocuring ink composition provided by each embodiment of the present application has good performance, good photocuring property, low initiator migration amount in the cured ink, and small odor, and has outstanding advantages in environmental protection and health compared with traditional photocuring ink compositions.

[0173] It can be understood by those skilled in the art that the features described in various embodiments of the present disclosure can be combined and / or integrated in various combinations, even if such combinations or integrations are not explicitly described in the present disclosure. In particular, the features described in various embodiments of the present disclosure can be combined and / or integrated in various combinations without departing from the spirit and teachings of the present disclosure. All these combinations and / or integrations fall within the scope of the present disclosure.

[0174] The embodiments of the present disclosure are described above. However, these embodiments are only for illustrative purposes, and are not intended to limit the scope of the present disclosure. Although each embodiment is described above separately, this does not mean that the measures in each embodiment cannot be used advantageously in combination. Without departing from the scope of the present disclosure, those skilled in the art can make various substitutions and modifications, and all these substitutions and modifications shall fall within the scope of the present disclosure.

Claims

1. A photocurable ink composition characterized in that, The light-curable ink composition comprises the following components in the following mass contents, based on the total mass of the light-curable ink composition: 0.5%-15% of a benzoyl formate photoinitiator; 8%-20% of an adhesive resin; 15%-70% of a polymerizable acrylate monomer or an oligomer thereof; 1%-50% of a coloring component; The benzoyl formate photoinitiator is formed by the reaction of a first compound having a structure shown in Formula (I), a second compound having a structure shown in Formula (II), and a third compound having a structure shown in Formula (III); A is selected from any one of a single bond, O, S, and CR2R3; R2 and R3 are each independently selected from any one of hydrogen, a C1-C8 linear alkyl group, and a C3-C8 branched alkyl group; R1 and R1' are each independently selected from any one of a C1-C4 alkyl group; R a is selected from the group consisting of hydrogen, -OH, C1-C 80 alkyl, C1-C 80 alkyl, wherein at least one CH2 group is replaced by oxygen or a phenyl ring; R b any one selected from C1-C8 straight chain alkylene or C3-C8 branched chain alkylene; q is selected from any one of an integer from 1 to 20; when q is greater than 2, the multiple R b the same or different; p is selected from any one of an integer from 2 to 10; R4is selected from any one of hydrogen, C 1- C 10 a straight chain alkyl or C 3- C 10 a branched chain alkyl; R5and R6are each independently selected from any one of hydrogen, C1-C 10 a straight chain alkyl or C 3- C 10 a branched chain alkyl, R5and R6are present individually or linked to each other to form a ring.

2. The photocurable ink composition according to claim 1, characterized by The mass content of the benzoyl formate photoinitiator is 3%-15%, based on the total mass of the light-curable ink composition.

3. The photocurable ink composition according to any one of claims 1 to 2, characterized in that, The adhesive resin comprises at least one non-reactive resin; Preferably, the non-reactive resin comprises at least one of a diallyl phthalate resin, a polyurethane resin, a polyester resin, a petroleum resin, a rosin ester resin, a poly(meth)acrylate, a cellulose derivative, a vinyl chloride-vinyl acetate copolymer, a polyamide resin, a polyvinyl acetal resin, and a butadiene-acrylonitrile copolymer. Preferably, the adhesive resin is preferably a diallyl phthalate resin.

4. The photocurable ink composition according to any one of claims 1 to 2, characterized by, The adhesive resin further comprises a compound having a polymerizable group; Preferably, the compound having a polymerizable group comprises at least one of an epoxy acrylate compound, a urethane acrylate compound, and a polyester acrylate compound.

5. The photocurable ink composition according to any one of claims 1 to 2, characterized by, The mass content of the adhesive resin is 10%-17%, based on the total mass of the light-curable ink composition.

6. The photocurable ink composition according to any one of claims 1 to 2, wherein The polymerizable acrylate monomer comprises at least one of a monofunctional (meth)acrylate and a multifunctional (meth)acrylate. Preferably, the monofunctional methacrylate includes at least one of ethyl (meth)acrylate, butyl (meth)acrylate, 2-ethylhexyl (meth)acrylate, nonyl (meth)acrylate, lauryl (meth)acrylate, tridecyl (meth)acrylate, cetyl (meth)acrylate, stearyl (meth)acrylate, isoamyl (meth)acrylate, isodecyl (meth)acrylate, isostearyl (meth)acrylate, cyclohexyl (meth)acrylate, benzyl (meth)acrylate, methoxyethyl (meth)acrylate, butoxyethyl (meth)acrylate, phenoxyethyl (meth)acrylate, phenoxydiethylene glycol (meth)acrylate, nonylphenoxyethyl (meth)acrylate, tetrahydrofurfuryl (meth)acrylate, glycidyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxy-3-phenoxypropyl (meth)acrylate, 3-chloro-2-hydroxypropyl (meth)acrylate, diethylaminoethyl (meth)acrylate, nonylphenoxyethyl tetrahydrofurfuryl (meth)acrylate, caprolactone-modified tetrahydrofurfuryl (meth)acrylate, isobornyl (meth)acrylate, dicyclopentyl (meth)acrylate, dicyclopentenyloxyethyl (meth)acrylate; Preferably, the multifunctional (meth)acrylate includes at least one of 1,4-butanediol di(meth)acrylate, 3-methyl-1,5-pentanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, 2-methyl-1,8-octanediol di(meth)acrylate, 2-butyl-2-ethyl-1,3-propanediol di(meth)acrylate, tricyclodecane dimethanol di(meth)acrylate, ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, di(meth)acrylates of dihydric alcohols such as polyethylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, di(meth)acrylate of tris(2-hydroxyethyl)isocyanurate, di(meth)acrylate, di(meth)acrylate, tri(meth)acrylate, glyceryl tri(meth)acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, ditrimethylolpropane tetra(meth)acrylate, poly(meth)acrylates of dipentaerythritol, tri(meth)acrylate, di(meth)acrylate, tri(meth)acrylate, di(meth)acrylate; Preferably, the polymerizable acrylate oligomer includes amine-modified polyether acrylate, amine-modified epoxy acrylate, amine-modified aliphatic acrylate, amine-modified polyester acrylate, amino (meth)acrylate, and the like amine-modified acrylate. thiol-modified polyester acrylate, thiol-modified (meth)acrylate such as thiol-modified (meth)acrylate; at least one of polyester (meth)acrylate, polyether (meth)acrylate, polyolefin (meth)acrylate, polystyrene (meth)acrylate, epoxy (meth)acrylate, urethane (meth)acrylate; Further preferably, the polymerizable acrylate monomer or oligomer thereof includes tetrafunctional (meth)acrylate.

7. The photocurable ink composition according to any one of claims 1 to 2, wherein The mass content of the polymerizable acrylate monomer or oligomer thereof is 30%-60% based on the total mass of the photocuring ink composition.

8. The photocurable ink composition according to any one of claims 1 to 2, wherein The mass content of the coloring ingredient is 10%-45% based on the total mass of the photocuring ink composition.

9. Use of the photocuring ink composition according to any one of claims 1-8 in an ink, in particular in an ultraviolet photocuring ink.

10. A method of making a photocured ink, characterized by, comprising the following steps: The photocuring ink is obtained by mixing a benzoyl formate photoinitiator, an adhesive resin, a polymerizable acrylate monomer or oligomer thereof, and a coloring ingredient.

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