Active energy ray-curable composition, active energy ray-curable ink, active energy ray-curable coating material, and article

Abstract

To provide an active energy ray-curable composition which is capable of forming a coating film having excellent adhesion and friction resistance.SOLUTION: The present invention provides an active energy ray-curable composition which contains a fatty acid-modified unsaturated polyester resin (A) and an active energy ray-curable monomer (B), in which the fatty acid-modified unsaturated polyester resin (A) is a reaction product of raw material components that include fatty acids and / or fats and oils, an α,β-unsaturated dicarboxylic acid serving as an acid component, and a polyhydric alcohol.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present invention relates to an active energy ray-curable composition, an active energy ray-curable ink, an active energy ray-curable paint, and an article. More specifically, the present invention relates to an active energy ray-curable composition, an active energy ray-curable ink, an active energy ray-curable paint, which are capable of forming a coating film having excellent adhesion and abrasion resistance to the surface of, for example, a plastic substrate, and an article having a coating film formed using these. [Background technology]

[0002] The active energy ray-curable composition contains a binder resin and an active energy ray-curable monomer such as an acrylic acid ester compound. When irradiated with active energy rays, a crosslinking reaction of the active energy ray-curable monomer occurs, causing the active energy ray-curable composition to instantly cure and form a tough coating.

[0003] As described above, by using an active energy ray-curable composition, a tough coating film can be formed instantly, and therefore, active energy ray-curable compositions have been used in a wide range of fields such as inks, paints, and coating agents.

[0004] For example, an active energy ray-curable composition is mixed with a pigment to be used as an active energy ray-curable ink. In general, the active energy ray-curable ink contains a pigment, a binder resin, an active energy ray-curable monomer such as an acrylic acid ester compound, a photopolymerization initiator, and additives.

[0005] Examples of binder resins used in active energy ray-curable inks include diallyl phthalate resins, polyester resins, and acrylic resins.

[0006] When an actinic ray-curable ink is printed on a plastic film having low polarity, such as polypropylene or polyethylene, and then irradiated with actinic ray to form a coating film, i.e., a film, there is a problem that the coating film exhibits poor adhesion to the plastic film.

[0007] The main cause of the poor adhesion is that irradiation with active energy rays causes a polymerization reaction of the active energy ray-curable monomer, which causes a sudden volumetric shrinkage of the active energy ray-curable ink, resulting in crazing and cracks in the coating film.

[0008] Acrylic esters are commonly used as active energy ray-curable monomers, but the polarity of acrylic esters is significantly different from that of plastics such as polypropylene and polyethylene, which also causes poor adhesion.

[0009] To address the poor adhesion of active energy ray-curable compositions, binder resins containing rosins or fatty acids are used.

[0010] Patent Document 1 discloses a rosin-modified alkyd resin, which is composed of a condensation polymer of a polyhydric alcohol with an acid component containing rosins, fatty acids, and polybasic acids, and has a specific acid value and solubility parameter (SP value), as a binder resin for an active energy ray-curable ink.

[0011] However, when the rosin-modified alkyd resin of Patent Document 1 is used as a binder resin for an active energy ray-curable ink, a coating film with excellent adhesion to a plastic substrate can be formed, but there is a problem in that the abrasion resistance of the coating film decreases.

[0012] Patent Document 2 discloses a reaction product of an addition reaction mixture of rosin acids (A) and an α,β-unsaturated carboxylic acid or its acid anhydride (B), a polyol (C), and a fatty acid (D) as a binder resin for an active energy ray-curable ink having excellent printability.

[0013] However, the α,β-unsaturated carboxylic acid or its acid anhydride (B) is used to form an addition reaction product with rosins via a Diels-Alder reaction, and therefore, the final reaction product described in Patent Document 2 does not contain any unsaturated bonds derived from the α,β-unsaturated carboxylic acid or its acid anhydride that are copolymerizable with an acrylic ester compound.

[0014] Furthermore, Patent Document 2 exemplifies unsaturated fatty acids such as tall oil fatty acid as fatty acids. However, the unsaturated bonds derived from unsaturated fatty acids have large steric hindrance and therefore cannot be copolymerized instantaneously with acrylic acid ester compounds upon irradiation with active energy rays.

[0015] Therefore, the binder resin of Patent Document 2 cannot copolymerize with the acrylic acid ester compound when irradiated with active energy rays, resulting in problems such as insufficient adhesion and abrasion resistance of the coating film. [Prior art documents] [Patent documents]

[0016] [Patent Document 1] Japanese Patent Publication No. 2020-128467 [Patent Document 2] Japanese Patent Publication No. 2022-065754 Summary of the Invention [Problem to be solved by the invention]

[0017] An object of the present invention is to provide an active energy ray-curable composition capable of forming a coating film having excellent adhesion and abrasion resistance. A further object of the present invention is to provide an active energy ray-curable ink containing the active energy ray-curable composition, an active energy ray-curable coating material, and an article having a printed layer printed using the active energy ray-curable ink. [Means for solving the problem]

[0018] As a result of intensive research into the above-mentioned problems, the present inventors have found that it is possible to provide an active energy ray-curable composition capable of forming a coating film having excellent adhesion and abrasion resistance by using, as a binder resin, a fatty acid-modified unsaturated polyester resin, which is a reaction product of raw material components including at least one of fatty acids and fats and oils, an acid component including α,β-unsaturated dicarboxylic acids, and a polyhydric alcohol.

[0019] That is, the present invention [1] is an active energy ray-curable composition containing a fatty acid-modified unsaturated polyester resin (A) and an active energy ray-curable monomer (B), The active energy ray-curable composition is characterized in that the fatty acid-modified unsaturated polyester resin (A) is a reaction product of raw material components including at least one of fatty acids and fats and oils, an α,β-unsaturated dicarboxylic acid as an acid component, and a polyhydric alcohol.

[0020] The present invention [2] includes the active energy ray-curable composition according to the above [1], wherein the raw material components further include rosins as an acid component.

[0021] The present invention [3] includes the active energy ray-curable composition according to the above [2], wherein the rosin is at least one selected from the group consisting of disproportionated rosin, hydrogenated rosin, and polymerized rosin.

[0022] The present invention [4] includes the active energy ray-curable composition according to the above [2] or [3], wherein in the production of the fatty acid-modified unsaturated polyester resin (A), the esterification reaction temperature after adding the α,β-unsaturated dicarboxylic acids is 230°C or lower.

[0023] The present invention [5] includes the active energy ray-curable composition according to any one of the above [1] to [4], wherein the fatty acid-modified unsaturated polyester resin (A) has a methanol tolerance of 120 g or less.

[0024] The present invention [6] includes an active energy ray-curable ink containing the active energy ray-curable composition according to any one of the above [1] to [5] and a pigment.

[0025] The present invention [7] includes an active energy ray-curable coating material containing the active energy ray-curable composition according to any one of the above [1] to [5] and a pigment.

[0026] The present invention [8] includes an article having a printed layer printed using the active energy ray-curable ink described in [6] above. [Effects of the Invention]

[0027] The active energy ray-curable composition of the present invention, and further the active energy ray-curable ink and active energy ray-curable paint containing the active energy ray-curable composition, can form a coating film having excellent adhesion and abrasion resistance. DETAILED DESCRIPTION OF THE INVENTION

[0028] [Active energy ray curable composition] The active energy ray-curable composition of the present invention contains a fatty acid-modified unsaturated polyester resin (A) and an active energy ray-curable monomer (B).

[0029] <Fatty acid modified unsaturated polyester resin (A)> The fatty acid-modified unsaturated polyester resin (A) is a reaction product obtained by reacting raw material components, which essentially contain at least one of fatty acids and fats and oils, an α,β-unsaturated dicarboxylic acid as an acid component, and a polyhydric alcohol.

[0030] (Fatty acids and oils) As a raw material component for constituting the fatty acid-modified unsaturated polyester resin (A), at least one of fatty acids and fats and oils is used.

[0031] In the fatty acid-modified unsaturated polyester resin (A), the use of at least one of fatty acids and oils as a raw material component can appropriately improve the flexibility of the coating film of the active energy ray-curable composition. This enables the active energy ray-curable composition to form a coating film with excellent adhesion to the substrate. Furthermore, the use of at least one of fatty acids and oils exhibits excellent affinity for pigments when the active energy ray-curable composition is applied to an active energy ray-curable ink due to the fatty acid skeleton of at least one of the fatty acids and oils. Therefore, the pigment can be dispersed with excellent dispersibility in the active energy ray-curable ink. Furthermore, excellent gloss can be imparted to the coating film (printed material) formed by printing the active energy ray-curable ink.

[0032] Furthermore, raw material components derived from biomass can also be used as raw material components for fatty acids, oils, etc. This can increase the content of biomass components and contribute to solving environmental problems such as global warming and the depletion of fossil resources.

[0033] Fatty acids include saturated fatty acids and unsaturated fatty acids, which are acid components having one carboxyl group per molecule and a monovalent saturated or unsaturated hydrocarbon group linked to the carboxyl group.

[0034] The fatty acids are not particularly limited, but preferably have 12 or more carbon atoms.

[0035] Examples of saturated fatty acids include lauric acid (12 carbon atoms), myristic acid (14 carbon atoms), palmitic acid (16 carbon atoms), and stearic acid (18 carbon atoms). Examples of unsaturated fatty acids include α-linolenic acid (18 carbon atoms), linoleic acid (18 carbon atoms), and oleic acid (18 carbon atoms). Among these fatty acids, saturated fatty acids are preferred because they have excellent physical properties such as solubility in the active energy ray-curable monomer (B) and curability, and stearic acid and lauric acid are more preferred. The fatty acids may be used alone or in combination of two or more.

[0036] The fatty acids do not need to be purified fatty acids, but may be mixed fatty acids containing two or more fatty acids. The mixed fatty acids may be a mixture of two or more fatty acids. Examples of mixed fatty acids include fatty acids derived from animal fats and oils, and fatty acids derived from vegetable fats and oils. Fatty acids derived from animal fats and oils and vegetable fats are preferred because they contain a large amount of fatty acids having 12 or more carbon atoms.

[0037] Examples of fatty acids derived from animal fats and oils include beef tallow fatty acids, lard fatty acids, fish oil fatty acids, and hydrogenated (hardened) fatty acids thereof. Examples of fatty acids derived from vegetable fats and oils include tall oil fatty acids, soybean oil fatty acids, linseed oil fatty acids, tung oil fatty acids, coconut oil fatty acids, and castor oil fatty acids.

[0038] The iodine value of the fatty acids is preferably 50 or less, more preferably 30 or less, even more preferably 5 or less, and particularly preferably 0. The iodine value of the fatty acids is preferably 0 or more. The iodine value is used as an indicator of the amount of unsaturated bonds contained in the fatty acids. Furthermore, when the fatty acids are mixed fatty acids, the iodine value is not the iodine value of each fatty acid contained in the mixed fatty acids, but the iodine value of the entire mixed fatty acid. The fewer the amount of unsaturated bonds in the fatty acids, the lower the iodine value. The fewer the number of unsaturated double bonds contained in the fatty acids, the more preferable it is, and the iodine value of the fatty acids is preferably 50 or less, and saturated fatty acids are particularly preferable as the fatty acids. By using fatty acids with a small number of unsaturated double bonds in this way, it is possible to reduce the loss of unsaturated bonds in the α,β-unsaturated dicarboxylic acids due to addition reactions such as the Ene reaction and the Diels-Alder reaction between the fatty acids and the α,β-unsaturated dicarboxylic acids. This makes it possible to sufficiently introduce unsaturated double bonds derived from the α,β-unsaturated dicarboxylic acids into the molecular structure of the fatty acid-modified unsaturated polyester resin (A).

[0039] The iodine value of fatty acids can be measured in accordance with JIS K 0070:1992.

[0040] In the present invention, fats and oils can be used instead of fatty acids as raw material components for constituting the fatty acid-modified unsaturated polyester resin (A). Only one of fatty acids and fats and oils may be used as raw material components, or both may be used.

[0041] The fats and oils include triglyceryl esters (triglycerides) of fatty acids and glycerin. The fatty acid moieties constituting the fats and oils can be introduced into the molecular structure of the fatty acid-modified unsaturated polyester resin (A) by subjecting the fatty acid moieties constituting the fats and oils to a transesterification reaction with the polyhydric alcohol used as a raw material component.

[0042] The fats and oils are not particularly limited, and examples thereof include animal fats and oils, vegetable fats and oils, etc. Among these, fats and oils in which at least one of the three fatty acids constituting the triglyceride has 12 or more carbon atoms are preferred.

[0043] Examples of animal fats and oils include beef tallow, lard, and fish oil. Examples of vegetable fats and oils include soybean oil, linseed oil, tung oil, coconut oil, castor oil, palm oil, and rapeseed oil. Coconut oil is preferred as the fat and oil. Recycled oils such as tempura oil that have been recovered and recycled after use for cooking may also be used. Recycle treatment methods generally include removal of sediment by filtration, decolorization, and the like. The fats and oils may be used alone or in combination of two or more.

[0044] The content of at least one of fatty acids and oils in the raw material components is preferably 3 to 50 parts by mass, more preferably 5 to 45 parts by mass, and even more preferably 15 to 30 parts by mass, per 100 parts by mass of the total amount of the raw material components. If the content is less than 3 parts by mass, depending on the combination of raw material components, the coating film (printed layer) of the active energy ray-curable composition may not be imparted with adequate flexibility, making adhesion poor. On the other hand, if the content exceeds 50 parts by mass, depending on the combination of raw material components, the coating film of the active energy ray-curable composition may become excessively flexible, resulting in reduced friction resistance (wear resistance), etc.

[0045] In the present invention, among fatty acids and oils and fats, only fatty acids may be used, only oils and fats may be used, or fatty acids and oils and fats may be used in combination. When fatty acids and oils and fats are used in combination, the total content of fatty acids and oils and fats is set to be within the above range.

[0046] (α,β-unsaturated dicarboxylic acids) As a raw material component for constituting the fatty acid-modified unsaturated polyester resin (A), an α,β-unsaturated dicarboxylic acid is used. Examples of the α,β-unsaturated dicarboxylic acid include an α,β-unsaturated dicarboxylic acid and anhydrides thereof, and an α,β-unsaturated aliphatic dicarboxylic acid and anhydrides thereof are preferred. In this embodiment, the α,β-unsaturated dicarboxylic acid refers to a dicarboxylic acid having two carboxy groups in one molecule and having an unsaturated bond between the α- and β-carbons of at least one of the carboxy groups.

[0047] The fatty acid-modified unsaturated polyester resin (A) contains an unsaturated double bond derived from an α,β-unsaturated dicarboxylic acid. This allows the fatty acid-modified unsaturated polyester resin (A) to copolymerize with the active energy ray-curable monomer (B) via the unsaturated double bond, forming a three-dimensional network structure in which the molecular chains of the fatty acid-modified unsaturated polyester resin (A) are crosslinked by the active energy ray-curable monomer (B). As a result, the abrasion resistance of the coating film of the active energy ray-curable composition can be improved.

[0048] Specific examples of α,β-unsaturated dicarboxylic acids include fumaric acid, maleic acid, itaconic acid, citraconic acid, mesaconic acid, glutaconic acid, and anhydrides thereof. The α,β-unsaturated dicarboxylic acids may be used alone or in combination of two or more.

[0049] Among the α,β-unsaturated dicarboxylic acids, from the viewpoint of ease of synthesis, fumaric acid, maleic acid, and maleic anhydride are preferred, fumaric acid and maleic anhydride are more preferred, and maleic anhydride is even more preferred.

[0050] The content of the α,β-unsaturated dicarboxylic acids in the raw materials is, for example, 5 parts by mass or more, preferably 7 parts by mass or more, more preferably 10 parts by mass or more, and even more preferably 15 parts by mass or more, relative to 100 parts by mass of the total amount of the raw materials. It is, for example, 50 parts by mass or less, preferably 40 parts by mass or less, more preferably 30 parts by mass or less, and even more preferably 25 parts by mass or less. When the content of the α,β-unsaturated dicarboxylic acids is less than 5 parts by mass, the abrasion resistance of the coating film may be reduced depending on the combination of raw materials. When the content of the α,β-unsaturated dicarboxylic acids is more than 50 parts by mass, the adhesion of the coating film to the substrate may be reduced depending on the combination of raw materials. In contrast, when the content of the α,β-unsaturated dicarboxylic acids is within the above range, an active energy ray-curable composition capable of forming a coating film with excellent adhesion and abrasion resistance can be obtained.

[0051] As described above, the raw material components used to obtain the fatty acid-modified unsaturated polyester resin (A) as a reaction product include at least one of fatty acids and fats and oils, and α,β-unsaturated dicarboxylic acids. This achieves both excellent coating film adhesion improvement based on the hydrocarbon group contained in at least one of the fatty acids and fats and oils, and improved coating film abrasion resistance due to the formation of a three-dimensional network structure based on the unsaturated double bonds derived from the α,β-unsaturated dicarboxylic acid.

[0052] (Polyhydric alcohol) A polyhydric alcohol is used as a raw material component for forming the fatty acid-modified unsaturated polyester resin (A). In this embodiment, the polyhydric alcohol refers to a compound (polyol) having two or more hydroxyl groups in one molecule.

[0053] Examples of polyhydric alcohols include trihydric or higher polyhydric alcohols and dihydric alcohols. The polyhydric alcohol preferably contains a trihydric or higher polyhydric alcohol, and for example, the polyhydric alcohol may contain a trihydric or higher polyhydric alcohol alone, but preferably contains a trihydric or higher polyhydric alcohol and a dihydric alcohol in combination.

[0054] Trihydric or higher polyhydric alcohols are compounds having three or more hydroxyl groups in one molecule. Examples of trihydric or higher polyhydric alcohols include trihydric alcohols such as glycerin, 1,1,1-trimethylolethane, 1,1,1-trimethylolpropane (hereinafter sometimes simply referred to as "trimethylolpropane"), trioxyisobutane, 1,2,3-butanetriol, 1,2,3-pentanetriol, 2,3,4-pentanetriol, and 1,2,5-hexanetriol; tetrahydric alcohols such as pentaerythritol; pentahydric or higher alcohols such as dipentaerythritol, glucose, sucrose, and sorbitol; and alkylene oxide (ethylene oxide, propylene oxide, etc.) adducts thereof. The trihydric or higher polyhydric alcohols may be used alone or in combination of two or more.

[0055] Among the trihydric or higher polyhydric alcohols, from the viewpoint of reactivity, trihydric or tetrahydric alcohols are preferred, trihydric alcohols are more preferred, glycerin and trimethylolpropane are more preferred, and glycerin is more preferred. By using a trihydric or higher polyhydric alcohol, an appropriate branched structure can be imparted to the fatty acid-modified unsaturated polyester resin (A), and a structure in which both α,β-unsaturated dicarboxylic acids and fatty acids are linked to the trihydric or higher polyhydric alcohol can be formed, thereby improving both the adhesion and abrasion resistance of the coating film of the active energy ray-curable composition.

[0056] The content of the trihydric or higher polyhydric alcohol in the raw material components is preferably 1 part by mass or more, more preferably 5 parts by mass or more, and even more preferably 8 parts by mass or more, per 100 parts by mass of the total amount of the raw material components. The content of the trihydric or higher polyhydric alcohol in the raw material components is preferably 30 parts by mass or less, more preferably 20 parts by mass or less, and even more preferably 15 parts by mass or less, per 100 parts by mass of the total amount of the raw material components. By setting the content of the trihydric or higher polyhydric alcohol to 1 part by mass or more and 30 parts by mass or less, a structure in which both an α,β-unsaturated dicarboxylic acid and a fatty acid are linked to the trihydric or higher polyhydric alcohol is appropriately formed in the fatty acid-modified unsaturated polyester resin (A), thereby improving the abrasion resistance of the coating film of the active energy ray-curable composition and allowing the coating film of the active energy ray-curable composition to maintain appropriate flexibility and high adhesion to the substrate.

[0057] The polyhydric alcohol preferably further contains a dihydric alcohol (diol). The use of a dihydric alcohol can impart appropriate flexibility to the coating film of the active energy ray-curable composition. This enables the active energy ray-curable composition to form a coating film with better adhesion to the substrate.

[0058] Dihydric alcohols are compounds having two hydroxyl groups per molecule. Examples of dihydric alcohols include ethylene glycol, 1,2-propanediol, 1,3-propanediol, 1,3-butanediol, 1,4-butanediol, neopentyl glycol, 1,5-pentanediol, 1,6-hexanediol, 1,8-octanediol, 1,10-decanediol, 4,4'-dihydroxyphenylpropane, 4,4'-dihydroxymethylmethane, diethylene glycol, triethylene glycol, polyethylene glycol (PEG), dipropylene glycol, polytetramethylene glycol (PTMG), polypropylene glycol (PPG), 1,4-cyclohexanedimethanol, 1,4-cyclohexanediol, bisphenol A, bisphenol F, and alkylene oxide (ethylene oxide, propylene oxide, etc.) adducts thereof. Dihydric alcohols may be used alone or in combination.

[0059] Among the dihydric alcohols, 1,3-propanediol and diethylene glycol are preferred. When diethylene glycol is used as the dihydric alcohol, the fatty acid-modified unsaturated polyester resin (A) has an ether bond due to the diethylene glycol having an ether bond. As a result, in the active energy ray-curable composition, the fatty acid-modified unsaturated polyester resin (A) exhibits excellent solubility in the active energy ray-curable monomer (B).

[0060] When the raw material components contain a dihydric alcohol, the content thereof is preferably 5 parts by mass or more, more preferably 10 parts by mass or more, relative to 100 parts by mass of the total amount of the raw material components. The content of the dihydric alcohol in the raw material components is preferably 30 parts by mass or less, more preferably 20 parts by mass or less, and more preferably 15 parts by mass or less. By setting the content of the dihydric alcohol within the above range, the active energy ray-curable composition can form a coating film having excellent adhesion to the substrate.

[0061] When the polyhydric alcohol contains a trihydric or higher polyhydric alcohol and a dihydric alcohol, the content of the trihydric or higher polyhydric alcohol in the polyhydric alcohol is preferably 30 mol% or more, more preferably 40 mol% or more. When the polyhydric alcohol contains a trihydric or higher polyhydric alcohol and a dihydric alcohol, the content of the trihydric or higher polyhydric alcohol in the polyhydric alcohol is preferably 60 mol% or less, more preferably 50 mol% or less. By setting the content of the trihydric or higher polyhydric alcohol at or above the above lower limit, a structure in which both α,β-unsaturated dicarboxylic acids and fatty acids are linked is frequently formed in the fatty acid-modified unsaturated polyester resin (A), thereby further improving the abrasion resistance of the coating film of the active energy ray-curable composition. By setting the content of the trihydric or higher polyhydric alcohol at or below the above upper limit, the amount of excess hydroxyl groups not subjected to the esterification reaction with α,β-unsaturated dicarboxylic acids and fatty acids can be reduced, and the methanol tolerance described below can be set low.

[0062] In the raw material components, the molar equivalent ratio of hydroxyl groups contained in the polyhydric alcohol to 1 molar equivalent of carboxyl groups contained in the raw material components is preferably 0.5 to 2.0, more preferably 0.9 to 1.3, even more preferably 0.95 to 1.15, and particularly preferably 1.0 to 1.1. By setting the molar equivalent ratio within the above range, it is possible to provide an active energy ray-curable composition that can form a coating film that has an excellent balance between adhesion and abrasion resistance.

[0063] The molar equivalent ratio of hydroxyl groups contained in the polyhydric alcohol to 1 molar equivalent of carboxyl groups contained in the raw material components can be calculated by dividing the total number of moles of hydroxyl groups contained in the polyhydric alcohol by the total number of moles of carboxyl groups contained in the raw material components.

[0064] The total number of moles of hydroxyl groups contained in the polyhydric alcohol can be calculated as follows. The polyhydric alcohol may contain multiple types of polyols, such as trihydric or higher polyhydric alcohols and dihydric alcohols. Therefore, for each polyhydric alcohol, the number of moles of the polyhydric alcohol contained in the raw material is first multiplied by the number of hydroxyl groups in one molecule of this polyhydric alcohol to obtain the number of moles of hydroxyl groups (M OH Next, calculate the number of moles of hydroxyl groups (M OH ) are summed, and the value obtained is the "total number of moles of hydroxyl groups contained in the polyhydric alcohol."

[0065] The raw material components contain multiple types of carboxylic acid components, such as fatty acids, α,β-unsaturated dicarboxylic acids, and, if necessary, rosins, as described below. Therefore, the total number of moles of carboxy groups contained in the raw material components can be calculated as follows: First, for each carboxylic acid component, the number of moles of the carboxylic acid component contained in the raw material component is multiplied by the number of carboxy groups in one molecule of this carboxylic acid component to obtain the number of moles of carboxy groups (M COOH Next, the mole number of carboxyl groups (M COOH ) are added together, and the value obtained is the "total number of moles of carboxy groups contained in the raw material components."

[0066] In addition, in the "total number of moles of carboxyl groups contained in the raw material ingredients," the number of moles of carboxyl groups of rosins (M COOH ) is calculated as follows. First, the acid value of the rosins contained in the raw material components is measured, and the amount of carboxy groups contained in the rosins per unit mass is calculated. Based on this amount of carboxy groups, the average molecular weight of the rosins is determined. Then, the number of moles of carboxy groups of the rosins (M COOH The acid value of rosins can be measured in accordance with JIS K5601-2-1 (1999).

[0067] (monohydric alcohol) The raw material components constituting the fatty acid-modified unsaturated polyester resin (A) may contain a monohydric alcohol in addition to the above-mentioned polyhydric alcohol.

[0068] A monohydric alcohol is a compound having one hydroxyl group per molecule. Examples of the monohydric alcohol include methanol, ethanol, propanol, and isopropanol. The monohydric alcohol may be used alone or in combination of two or more.

[0069] (rosins) The raw material components constituting the fatty acid-modified unsaturated polyester resin (A) preferably contain rosins as other acid components (carboxylic acids).

[0070] The fatty acid-modified unsaturated polyester resin (A) preferably contains rosins as other acid components contained in the raw material components, thereby improving the abrasion resistance of the coating film of the active energy ray-curable composition.

[0071] Examples of rosins include unmodified rosin (unmodified rosin), modified rosin (rosin derivative), etc. The rosins may be used alone or in combination of two or more.

[0072] Examples of unmodified rosins include natural rosin. Natural rosin is a natural resin whose main component is resin acid. Resin acid is a compound having a carboxy group derived from trees. Specific examples of resin acids include resin acids having conjugated double bonds such as abietic acid, palustric acid, neoabietic acid, and levopimaric acid, and resin acids not having conjugated double bonds such as dehydroabietic acid, dihydroabietic acid, and tetrahydroabietic acid.

[0073] Examples of natural rosins include tall oil rosin, gum rosin, and wood rosin. Gum rosin is preferred. One type of natural rosin may be used alone, or two or more types may be used in combination.

[0074] The rosin modified product is a modified product of the above-mentioned unmodified rosin, and examples thereof include acid-modified rosin, stabilized rosin, etc. The rosin modified product may be used alone or in combination of two or more types.

[0075] Acid-modified rosin is a modified product obtained by acid-modifying unmodified rosin. The acid modification is not particularly limited, but can be carried out, for example, by adding (reacting) a known α,β-unsaturated carboxylic acid to unmodified rosin using a Diels-Alder reaction or the like. Examples of α,β-unsaturated carboxylic acids include α,β-unsaturated carboxylic acids and their anhydrides. Specific examples include fumaric acid, maleic acid, maleic anhydride, itaconic acid, citraconic acid, citraconic anhydride, acrylic acid, and methacrylic acid. The α,β-unsaturated carboxylic acids may be used alone or in combination of two or more.

[0076] The stabilized rosin is a modified product obtained by stabilizing the unmodified rosin described above. The stabilization treatment reduces or eliminates the conjugated double bonds in the resin acid having conjugated double bonds. Specific examples of the stabilization treatment include hydrogenation, disproportionation, and polymerization, with hydrogenation and disproportionation being preferred.

[0077] Examples of stabilized rosins include hydrogenated rosin obtained by hydrogenating natural rosin, disproportionated rosin obtained by disproportionating natural rosin, and polymerized rosin obtained by polymerizing natural rosin. Stabilized rosin also includes a hydrogenated polymerized rosin. The stabilized rosins may be used alone or in combination of two or more.

[0078] As the stabilized rosin, hydrogenated rosin and disproportionated rosin are preferable, and disproportionated rosin is preferable.

[0079] As the rosin, a modified rosin is preferred, and a stabilized rosin is more preferred. This makes it possible to obtain a fatty acid-modified unsaturated polyester resin (A) having a sufficient number of unsaturated bonds to be copolymerizable with the active energy ray-curable monomer (B) described later, and to enable a coating film of the active energy ray-curable composition to exhibit high abrasion resistance.

[0080] If stabilized rosin is not used as the rosin, a Diels-Alder reaction occurs between the unmodified rosin, such as abietic acid having the above-mentioned conjugated double bond, and α,β-unsaturated dicarboxylic acids, which may make it difficult to retain the double bond derived from the α,β-unsaturated dicarboxylic acids in the fatty acid-modified unsaturated polyester resin (A). As a result, the opportunity for copolymerization between the fatty acid-modified unsaturated polyester resin (A) and the active energy ray-curable monomer (B) is reduced, which may result in insufficient abrasion resistance of the coating film.

[0081] In contrast, the use of stabilized rosin as the rosin can prevent the Diels-Alder reaction between the stabilized rosin and α,β-unsaturated dicarboxylic acids. Therefore, the unsaturated double bonds derived from the α,β-unsaturated dicarboxylic acids can remain in the fatty acid-modified unsaturated polyester resin (A). Therefore, a copolymer can be reliably formed by copolymerizing the fatty acid-modified unsaturated polyester resin (A) with the active energy ray-curable monomer (B), thereby improving the abrasion resistance of the coating film (printed layer).

[0082] The content of the rosin modified product in the rosins is preferably 90% by mass or more, more preferably 95% by mass or more, still more preferably 98% by mass or more, and particularly preferably 100% by mass.

[0083] The content of rosins in the raw material components is, relative to 100 parts by mass of the total amount of the raw material components, for example, 5 parts by mass or more, preferably 7 parts by mass or more, and preferably 15 parts by mass or more, and for example, 60 parts by mass or less, preferably 50 parts by mass or less, more preferably 40 parts by mass or less, and even more preferably 30 parts by mass or less. By keeping the rosin content within the above range, the adhesion and abrasion resistance of the coating film (printed layer) can be improved.

[0084] Furthermore, as will be described later, rosins may contain metal atoms as unavoidable impurities, but when rosins are included in the raw material components, by setting the content ratio of rosins to the above upper limit or less, it is possible to prevent the content of metal atoms from becoming undesirably high during the production of the fatty acid-modified unsaturated polyester resin (A). Therefore, in the second esterification step described later, it is possible to reduce the occurrence of gelation of the fatty acid-modified unsaturated polyester resin (A) caused by the metal atoms acting as a polymerization catalyst to promote the polymerization of α,β-unsaturated dicarboxylic acids.

[0085] (Aromatic carboxylic acids) The raw material components constituting the fatty acid-modified unsaturated polyester resin (A) preferably contain aromatic carboxylic acids as other acid components. The use of aromatic carboxylic acids can impart excellent gloss to the coating film (printed matter).

[0086] Examples of aromatic carboxylic acids include aromatic carboxylic acids and their anhydrides. Examples of aromatic carboxylic acids include benzoic acid, p-tert-butylbenzoic acid, salicylic acid, naphthoic acid, phthalic acid, phthalic anhydride, trimellitic acid, trimellitic anhydride, and substituted derivatives of these aromatic carboxylic acids in which at least one alkyl group is introduced into the aromatic ring. Aromatic carboxylic acids may be used alone or in combination of two or more.

[0087] The content of aromatic carboxylic acids in the raw material components is, for example, preferably 40 parts by mass or less, more preferably 30 parts by mass or less, and for example, preferably 1 part by mass or more, more preferably 5 parts by mass or more, relative to 100 parts by mass of the total amount of the raw material components.

[0088] The raw material components constituting the fatty acid-modified unsaturated polyester resin (A) may contain, as another acid component, an aliphatic dicarboxylic acid that does not contain a linear unsaturated hydrocarbon chain. Examples of the aliphatic dicarboxylic acid include aliphatic dicarboxylic acids that do not contain a linear unsaturated hydrocarbon chain and their anhydrides.

[0089] Examples of aliphatic dicarboxylic acids include chain saturated aliphatic dicarboxylic acids such as oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, suberic acid, azelaic acid, sebacic acid, and anhydrides thereof; and cyclic aliphatic dicarboxylic acids such as tetrahydrophthalic acid, cyclopropane-1,1-dicarboxylic acid, cyclobutane-1,1-dicarboxylic acid, and anhydrides thereof. Among these, adipic acid, tetrahydrophthalic acid, and anhydrides thereof are more preferred. The aliphatic dicarboxylic acids may be used alone or in combination of two or more.

[0090] The content of aliphatic dicarboxylic acids in the raw material components is, for example, preferably 30 parts by mass or less, more preferably 25 parts by mass or less, more preferably 10 parts by mass or less, and for example, preferably 1 part by mass or more, relative to 100 parts by mass of the total amount of the raw material components.

[0091] (epoxy compounds) Furthermore, the raw material components for obtaining the fatty acid-modified unsaturated polyester resin (A) may contain an epoxy compound.

[0092] Examples of epoxy compounds include allyl glycidyl ether, phenol (EO)5 glycidyl ether (CAS number: 54140-67-9), lauryl alcohol (EO)15 glycidyl ether (CAS number: 86630-59-3), glycerol polyglycidyl ether, diglycerol polyglycidyl ether, polyglycerol polyglycidyl ether, sorbitol polyglycidyl ether, ethylene glycol diglycidyl ether, diethylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, propylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, and epoxy cresol novolac. Epoxy compounds may be used alone or in combination of two or more.

[0093] The content of the epoxy compound in the raw material components may be appropriately set depending on the purpose and application.

[0094] The fatty acid-modified unsaturated polyester resin (A) is a reaction product containing unsaturated double bonds derived from α,β-unsaturated dicarboxylic acids contained as raw material components. Therefore, when unsaturated fatty acids or rosins are used, it is preferable that the unsaturated double bonds derived from the α,β-unsaturated dicarboxylic acids are not lost by addition reactions such as the ene reaction or Diels-Alder reaction with the unsaturated fatty acids or rosins.

[0095] From this viewpoint, the fatty acid-modified unsaturated polyester resin (A) is preferably a reaction product (polycondensate) obtained by esterifying an ester of at least one of fatty acids and fats and oils, and optionally rosins, aromatic dicarboxylic acids, and aliphatic dicarboxylic acids with a trihydric or higher polyhydric alcohol, with an α,β-unsaturated dicarboxylic acid.

[0096] In the above reaction product, an acid component other than α,β-unsaturated dicarboxylic acids is first reacted with a polyhydric alcohol having a valence of 3 or more, and then the α,β-unsaturated dicarboxylic acids are reacted. This allows the steric hindrance of the polyhydric alcohol having a valence of 3 or more to suppress the addition reaction between the α,β-unsaturated dicarboxylic acids and components containing unsaturated bonds, such as fatty acids and rosins, and the α,β-unsaturated dicarboxylic acids. Therefore, the unsaturated double bonds derived from the α,β-unsaturated dicarboxylic acids can be introduced into the molecular structure of the above reaction product without being lost.

[0097] Furthermore, when a dihydric alcohol is further used as the polyhydric alcohol, the fatty acid-modified unsaturated polyester resin (A) is preferably a reaction product obtained by esterifying an ester of at least one of fatty acids and fats and oils, and, if necessary, rosins, aromatic dicarboxylic acids, and aliphatic dicarboxylic acids with a trihydric or higher polyhydric alcohol, with an α,β-unsaturated dicarboxylic acid and a dihydric alcohol.

[0098] In such a reaction product, the unsaturated double bond derived from the α,β-unsaturated dicarboxylic acid can be introduced into the molecular structure of the reaction product without being lost, as in the case described above. Furthermore, by first reacting a trihydric or higher polyhydric alcohol and then reacting a dihydric alcohol, the final reaction product can be given an appropriate branched structure. This allows the formation of a coating film with appropriate flexibility and hardness, and provides a coating film that combines adhesion to the substrate with abrasion resistance.

[0099] The fatty acid-modified unsaturated polyester resin (A) can provide coating film flexibility due to the fatty acids or oils contained in the raw material components, resulting in excellent coating film adhesion. Furthermore, the unsaturated bonds derived from α,β-unsaturated dicarboxylic acids copolymerize with active energy ray-curable monomers upon exposure to active energy rays, resulting in excellent coating film abrasion resistance.

[0100] The fatty acid-modified unsaturated polyester resin (A) has a viscosity of 1.01 x 10 at 25°C. 5The fatty acid-modified unsaturated polyester resin (A) is preferably in a liquid state or a solid state with a softening point of 70°C or lower at Pa (1 atm). A fatty acid-modified unsaturated polyester resin (A) that is in a liquid state or a solid state with a low softening point has excellent compatibility with the active energy ray-curable monomer (B). Therefore, the content of the active energy ray-curable monomer (B) in the active energy ray-curable composition can be increased, and a coating film with a high crosslink density can be formed, thereby further improving the abrasion resistance of the coating film. Furthermore, because the fatty acid-modified unsaturated polyester resin (A) is in a liquid state or a solid state with a low softening point, an active energy ray-curable composition containing the fatty acid-modified unsaturated polyester resin (A) can be prepared as a liquid with low viscosity. Therefore, when the active energy ray-curable composition is applied to a substrate, the active energy ray-curable composition spreads uniformly over the substrate, thereby forming a coating film with excellent adhesion.

[0101] When the fatty acid-modified unsaturated polyester resin (A) is solid, the softening point of the fatty acid-modified unsaturated polyester resin (A) is, as described above, preferably 70°C or lower, more preferably 60°C or lower, and also preferably 40°C or higher, more preferably 45°C or higher.

[0102] The softening point of the fatty acid-modified unsaturated polyester resin (A) in a solid state can be measured in accordance with ASTM D6090 (1997). A measuring device such as the "Dropping Point System DP70" manufactured by Mettler Toledo can be used for the measurement. When using the measuring device, the softening point can be measured as follows: First, a stainless steel cup having a top diameter of 10 mm, a bottom hole with a diameter of 6.35 mm, and a depth of 10 mm is filled with the fatty acid-modified unsaturated polyester resin (A). The cup is then placed in the measuring device. The temperature is increased from 40°C at a rate of 3°C / min. The temperature at which the fatty acid-modified unsaturated polyester resin (A) is detected by a detector installed 19 mm vertically below the hole in the bottom of the cup is measured, and this temperature can be taken as the softening point.

[0103] The methanol tolerance of the fatty acid-modified unsaturated polyester resin (A) at 25°C is preferably 120 g or less, more preferably 90 g or less, and even more preferably 70 g or less. When the methanol tolerance of the fatty acid-modified unsaturated polyester resin (A) is below the above upper limit, it can be said that the methanol tolerance is set low. In contrast, low-polarity plastic films such as those made of polypropylene or polyethylene terephthalate are frequently selected as substrates to which the active energy ray-curable composition is applied. Therefore, as described above, by setting the methanol tolerance low, the interaction between the coating film formed using the active energy ray-curable composition and the substrate is improved, and a coating film with excellent adhesion can be formed on the substrate. Furthermore, when the raw material components contain both fatty acids and / or fats and oils and rosins as acid components, the fatty acid-modified unsaturated polyester resin (A), which is the reaction product of these raw material components, can be said to have a well-balanced ester bond between the acid component and the polyhydric alcohol, making it possible to form a coating film on the substrate with excellent adhesion and abrasion resistance. The methanol tolerance of the fatty acid-modified unsaturated polyester resin (A) at 25°C is preferably 25 g or more. By increasing the methanol tolerance to 25 g or more, it is possible to reduce oil penetration into the coating film on the substrate, thereby improving the oil resistance (oil repellency) of the coating film.

[0104] The methanol tolerance of the fatty acid-modified unsaturated polyester resin (A) at 25°C can be measured according to the following procedure. First, 5 g of the fatty acid-modified unsaturated polyester resin (A) is dissolved in 50 mL of toluene in a transparent glass Erlenmeyer flask (volume 100 mL) to obtain a reference solution. While stirring the reference solution at 25°C, methanol is added dropwise to the reference solution, and the mass (g) of methanol added until the reference solution becomes cloudy is determined. This mass (g) of methanol is used as the methanol tolerance of the fatty acid-modified unsaturated polyester resin (A) at 25°C. The Erlenmeyer flask is placed on a newspaper, and with the newspaper and the Erlenmeyer flask in contact, characters (10-point) printed on the newspaper are visually observed through the reference solution in the Erlenmeyer flask. The point at which the characters become indistinguishable due to the cloudiness of the reference solution is considered to be the "clouding of the reference solution."

[0105] The acid value of the fatty acid-modified unsaturated polyester resin (A) is preferably 1 mgKOH / g or more, more preferably 5 mgKOH / g or more, and preferably 30 mgKOH / g or less, more preferably 25 mgKOH / g or less, and even more preferably 20 mgKOH / g or less. When the acid value of the fatty acid-modified unsaturated polyester resin (A) is within the above range, an active energy ray-curable composition capable of forming a coating film having excellent adhesion can be obtained.

[0106] The acid value of the fatty acid-modified unsaturated polyester resin (A) can be measured according to the following procedure. 1 g of the fatty acid-modified unsaturated polyester resin (A) is dissolved in 20 mL of a mixed solvent of xylene and ethanol (xylene:ethanol = 2:1 (mass ratio)) to obtain a mixed solution. Then, 3 mL of a 3 mass% phenolphthalein solution is added to the mixed solution as an indicator, and the acid value (mgKOH / g) is determined by neutralization titration with a 0.1 mol / L ethanolic potassium hydroxide solution.

[0107] The weight-average molecular weight of the fatty acid-modified unsaturated polyester resin (A) is preferably 2,000 or more, more preferably 3,000 or more. The weight-average molecular weight of the fatty acid-modified unsaturated polyester resin (A) is preferably 50,000 or less, more preferably 20,000 or less, and more preferably 15,000 or less. When the weight-average molecular weight of the fatty acid-modified unsaturated polyester resin (A) is 2,000 or more, the abrasion resistance of the coating film formed using the fatty acid-modified unsaturated polyester resin (A) can be improved. When the weight-average molecular weight of the fatty acid-modified unsaturated polyester resin (A) is 50,000 or less, gelation and excessive increase in molecular weight of the fatty acid-modified unsaturated polyester resin (A) are reduced, and the solubility of the fatty acid-modified unsaturated polyester resin (A) in the active energy ray-curable monomer (B) can be improved. As a result, a coating film formed using the active energy ray-curable composition can be formed with a high crosslink density, thereby further improving the abrasion resistance of the coating film.

[0108] The weight-average molecular weight of the fatty acid-modified unsaturated polyester resin (A) refers to the value obtained by converting the molecular weight measured by gel permeation chromatography (GPC) into polystyrene equivalents. For example, it can be measured under the following measurement conditions. The fatty acid-modified unsaturated polyester resin (A) is dissolved in tetrahydrofuran to obtain a measurement sample with a fatty acid-modified unsaturated polyester resin (A) concentration of 0.5 mass%. Using this measurement sample, the weight-average molecular weight of the fatty acid-modified unsaturated polyester resin (A) can be measured using a gel permeation chromatograph (GPC) equipped with a refractive index detector (RID) under the following measurement equipment and measurement conditions. Measuring device: Showa Denko "Shodex GPC-101" Column: Showa Denko "KF-802" + "KF-806L" x 2 Detector: Shodex RI-71 (differential refractive index detector) Data processing: "480IIXP", Standard polystyrene (Showa Denko: "S-0.5", "S-1.0", "S-1.2", "S-1.9", "S-2.9", "S-3.1", "S-4.4", "S-5.1", "S-7.2", "S-19.6", "S-49.2", "S-114", "S-257", "S-778", "S-1320", "S-7450") Column temperature: 40℃ Solvent: tetrahydrofuran Flow rate: 1.0mL / min Sample concentration: 0.5% by mass Injection amount: 100μm

[0109] <Method for producing fatty acid modified unsaturated polyester resin (A)> The method for producing the fatty acid-modified unsaturated polyester resin (A) is not particularly limited, and known methods can be used.

[0110] The fatty acid-modified unsaturated polyester resin (A) can be produced by mixing and heating raw material components containing at least one of fatty acids and fats and oils, an α,β-unsaturated dicarboxylic acid as an acid component, and a polyhydric alcohol, optionally in the presence of a solvent, to cause an esterification reaction. In producing the fatty acid-modified unsaturated polyester resin (A), the esterification reaction temperature after adding the α,β-unsaturated dicarboxylic acid following the esterification reaction between the fatty acids and at least one of fats and oils and the polyhydric alcohol is preferably set to 230°C or lower. This allows the esterification reaction to proceed while suppressing the loss of the unsaturated double bonds in the α,β-unsaturated dicarboxylic acids due to polymerization between the α,β-unsaturated dicarboxylic acids themselves, thereby allowing the unsaturated double bonds derived from the α,β-unsaturated dicarboxylic acids to be introduced into the fatty acid-modified unsaturated polyester resin (A). The esterification reaction temperature after adding the α,β-unsaturated dicarboxylic acid is preferably 180°C or higher.

[0111] The esterification reaction may be a direct esterification reaction involving dehydration of an acid component and an alcohol component, or a transesterification reaction. The esterification reaction may be appropriately selected depending on the raw material components used.

[0112] The solvent is not particularly limited, but examples thereof include petroleum hydrocarbon solvents such as hexane and mineral spirits; aromatic hydrocarbon solvents such as benzene, toluene, and xylene; ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, diisobutyl ketone, and cyclohexanone; ester solvents such as methyl acetate, ethyl acetate, butyl acetate, γ-butyrolactone, and propylene glycol monomethyl ether acetate; and organic solvents such as aprotic polar solvents such as N,N-dimethylformamide, N,N-dimethylacetamide, dimethyl sulfoxide, N-methylpyrrolidone, and pyridine. The solvents may be used alone or in combination. The blending ratio of the solvents is not particularly limited and can be appropriately determined depending on the purpose and application.

[0113] For example, by heating the raw material components in the presence of a solvent that can form an azeotropic distillate with water (for example, an azeotropic dehydrating agent such as xylene or toluene), the esterification reaction can be initiated and the water produced by the reaction can be distilled off. After the reaction is complete, the solvent may be removed as needed. Alternatively, for example, the raw material components can be heated in the absence of a solvent to initiate the esterification reaction, and the water produced can be distilled off by a known method.

[0114] The reaction of the raw material components is preferably carried out in the presence of an esterification catalyst. The esterification catalyst is not particularly limited, but examples thereof include organic sulfonic acids such as benzenesulfonic acid, p-toluenesulfonic acid, p-dodecylbenzenesulfonic acid, methanesulfonic acid, and ethanesulfonic acid; mineral acids such as sulfuric acid and hydrochloric acid; metal catalysts such as tetrabutyl zirconate, tetraisopropyl titanate, tetraisobutyl titanate, aluminum oxide, titanium oxide, magnesium oxide, magnesium hydroxide, magnesium acetate, calcium oxide, calcium hydroxide, calcium acetate, zinc oxide, and zinc acetate; trifluoromethylsulfuric acid, trifluoromethylacetic acid, and the like. The esterification catalyst may be used alone or in combination of two or more. The addition ratio of the esterification catalyst is not particularly limited and can be appropriately determined depending on the purpose and application.

[0115] The reaction of the raw material components is preferably carried out under atmospheric pressure in an inert gas atmosphere. In the reaction of the raw material components, the heating temperature of the raw material components is preferably 150 to 280° C., and more preferably 200 to 250° C. The heating time is preferably 4 to 20 hours, and more preferably 6 to 15 hours.

[0116] In the reaction of the raw material components, the order in which the raw material components are reacted, i.e., the order in which the raw material components are mixed, is not particularly limited. All of the raw material components may be mixed and reacted at the same time, or the raw material components may be mixed and reacted in any order.

[0117] For example, when fatty acids are used from among fatty acids and fats and oils, and a polyhydric alcohol having a valence of 3 or more is used as the polyhydric alcohol, the following production method is preferably used.

[0118] The fatty acid-modified unsaturated polyester resin (A) can be produced by the following method: a first esterification step of directly esterifying fatty acids, and optionally rosins, aromatic dicarboxylic acids, and aliphatic dicarboxylic acids with a trihydric or higher polyhydric alcohol to obtain an esterified product; A preferred example of the method includes a second esterification step in which, after completion of the first esterification step, the esterified product is subjected to a direct esterification reaction with an α,β-unsaturated dicarboxylic acid and, if necessary, a dihydric alcohol to obtain a fatty acid-modified unsaturated polyester resin (A).

[0119] In the above method, when the raw material components contain rosins, an esterification reaction of rosins, fatty acids, and trihydric or higher polyhydric alcohols is carried out in the first esterification step, and then an esterification reaction of α,β-unsaturated dicarboxylic acids is carried out in the second esterification step. This reduces the addition of α,β-unsaturated dicarboxylic acids to the resin acid through the Diels-Alder reaction, even when the rosins contain a resin acid having a conjugated double bond, and allows sufficient introduction of unsaturated bonds derived from the α,β-unsaturated dicarboxylic acids into the fatty acid-modified unsaturated polyester resin (A).

[0120] Furthermore, in the above method, when the raw material components further contain a dihydric alcohol, the heating temperature during the esterification reaction can be increased by first carrying out the esterification reaction of rosins, fatty acids, and trihydric or higher polyhydric alcohols prior to the reaction of α,β-unsaturated dicarboxylic acids and dihydric alcohols in the first esterification step. This allows the esterification reaction of rosins, fatty acids, and trihydric or higher polyhydric alcohols to proceed sufficiently, and even when the content of rosins and fatty acids is high, the methanol tolerance of the finally obtained fatty acid-modified unsaturated polyester resin (A) can be reduced.

[0121] The reaction temperature in the first esterification step is preferably 210° C. or higher, more preferably 220° C. or higher, and even more preferably higher than 230° C. The reaction temperature in the first esterification step is preferably 280° C. or lower, more preferably 250° C. or lower. In order to allow the esterification reaction to proceed sufficiently, the first esterification step is preferably carried out until the acid value of the esterified product becomes 10 mgKOH / g or lower.

[0122] The reaction temperature of the second esterification step is, for example, preferably 180°C or higher, more preferably 190°C or higher, and, for example, preferably 230°C or lower. That is, in the second esterification step, the esterified product obtained in the first esterification step is heated at a relatively low temperature with an α,β-unsaturated dicarboxylic acid and a dihydric alcohol to further esterify, thereby obtaining a fatty acid-modified unsaturated polyester resin (A). Thus, when the reaction temperature of the second esterification step is within the above range, even if the system (raw material components) contains rosins (particularly unmodified rosin) as other acid components, unsaturated bonds (unsaturated double bonds) derived from the α,β-unsaturated dicarboxylic acids copolymerizable with the active energy ray-curable monomer (B) can be retained in the fatty acid-modified unsaturated polyester resin (A) at a high residual rate. The second esterification step is preferably carried out until the acid value of the fatty acid-modified unsaturated polyester resin (A) reaches, for example, 30 mgKOH / g or less, more preferably 20 mgKOH / g or less. This allows the esterification reaction to proceed sufficiently in the second esterification step, thereby reducing the methanol tolerance of the finally obtained fatty acid-modified unsaturated polyester.

[0123] In the second esterification step, although not particularly limited, it is preferable to cool the temperature in the system to 180°C or less, particularly 150 to 180°C, and then heat the esterified product, α,β-unsaturated dicarboxylic acids, and optionally a dihydric alcohol at the above reaction temperature to carry out the esterification reaction, thereby more significantly exhibiting the above-mentioned effects.

[0124] The acid value of the esterified product obtained in the first esterification step and the acid value of the fatty acid-modified unsaturated polyester resin (A) obtained in the second esterification step can each be measured in accordance with JIS K5601-2-1 (1999).

[0125] When rosins are included in the raw material components, the rosins may contain rosin metal salts as unavoidable impurities. The metal atoms contained in such rosin metal salts can act as catalysts for the esterification reaction in the first esterification step. Meanwhile, in the second esterification step, the metal atoms can act as polymerization catalysts that promote the polymerization of α,β-unsaturated dicarboxylic acids. As a result, the fatty acid-modified unsaturated polyester resin (A) may become too high in molecular weight and gel. Therefore, by using a polymerization inhibitor, the polymerization of α,β-unsaturated dicarboxylic acids in the second esterification step can be suppressed, thereby reducing the gelation of the fatty acid-modified unsaturated polyester resin (A).

[0126] Examples of metal atoms in the rosin metal salt include at least one of iron, copper, zinc, aluminum, and magnesium atoms. The content of the rosin metal salt in rosins is extremely small.

[0127] Examples of polymerization inhibitors include phenolic polymerization inhibitors such as (alkyl)phenols, p-methoxyphenol, o-isopropylphenol, catechol, resorcinol, t-butylcatechol, pyrogallol, dibutylcresol, and guaiacol; nitroso-based polymerization inhibitors such as nitrosobenzene, aluminum N-nitrosophenylhydroxylamine, tri-p-nitrophenylmethyl, picric acid, cupferron, butyraldoxime, methyl ethyl ketoxime, and cyclohexanone oxime; quinone-based polymerization inhibitors such as hydroquinone, t-butylhydroquinone, p-benzoquinone, and 2,5-di-tert-butyl-p-benzoquinone; and piperidine-based polymerization inhibitors such as phenothiazine. The polymerization inhibitors may be used alone or in combination of two or more.

[0128] The amount of the polymerization inhibitor is preferably 0.001 to 5 parts by mass, more preferably 0.01 to 1 part by mass, relative to 100 parts by mass of the total amount of the raw material components. By setting the amount of the polymerization inhibitor within the above range, polymerization between α,β-unsaturated dicarboxylic acids in the second esterification step can be sufficiently suppressed.

[0129] When a polymerization inhibitor is used in the second esterification step, the fatty acid-modified unsaturated polyester resin (A) obtained by the above-mentioned production method is obtained in the form of a mixture with the polymerization inhibitor. That is, when a polymerization inhibitor is used in the second esterification step, a composition containing the fatty acid-modified unsaturated polyester resin (A) and the polymerization inhibitor is obtained. Then, by adding the active energy ray-curable monomer (B) and, if necessary, a polymerization initiator and a curing accelerator, etc. to this composition, a fatty acid-modified unsaturated polyester composition can be obtained. Furthermore, if necessary, a polymerization inhibitor may be further added to the fatty acid-modified unsaturated polyester composition.

[0130] In the method for producing the fatty acid-modified unsaturated polyester resin (A), when fats and oils are used among fatty acids and fats and oils, it is preferable to carry out a transesterification step instead of the first esterification step described above.

[0131] In the transesterification step, an intermediate reaction product is obtained by transesterifying fats and oils with a trihydric or higher polyhydric alcohol. The transesterification reaction results in an intermediate reaction product in which a fatty acid moiety in the fats and oils is introduced into the polyhydric alcohol. A known catalyst can also be used in the transesterification reaction.

[0132] The reaction temperature in the transesterification step is preferably 220° C. or higher, more preferably 230° C. or higher, and even more preferably 240° C. or higher. The reaction temperature in the transesterification step is preferably 280° C. or lower, and more preferably 250° C. or lower.

[0133] After the transesterification step is completed, the intermediate reaction product obtained by the transesterification reaction can be regarded as the esterified product obtained in the first esterification step described above, and the second esterification step described above can be carried out.

[0134] After the transesterification step, a first esterification step and a second esterification step can be carried out, if necessary, by adding other acid components. For example, the first esterification step can be carried out by directly esterifying the intermediate reaction product obtained in the transesterification step with at least one of rosins, aromatic dicarboxylic acids, and aliphatic dicarboxylic acids to obtain an esterified product. The second esterification step can then be carried out in the same manner as described above. When the transesterification step is carried out, the reaction temperature in the first esterification step is preferably 180°C or higher, more preferably 190°C or higher, and preferably 230°C or lower. The reaction temperature in the second esterification step and the polymerization inhibitor used in the second esterification step are the same as those described above, and therefore will not be described here.

[0135] However, it is generally difficult to adjust the weight-average molecular weight during the synthesis of a fatty acid-modified unsaturated polyester resin (A). Specifically, as the reaction of the raw material components begins, the molecular weight of the reactants gradually increases. However, by the end of the reaction, the molecular weight of the reactants has increased considerably. Reaction between these reactants can lead to a rapid increase in molecular weight or gelation, making it difficult to obtain a fatty acid-modified unsaturated polyester resin (A) with a relatively low weight-average molecular weight. However, the above-described production method can reduce the occurrence of a rapid increase in molecular weight or gelation, making it easy to produce a fatty acid-modified unsaturated polyester resin (A) with a relatively low weight-average molecular weight. Specifically, a fatty acid-modified unsaturated polyester resin (A) with a molecular weight of preferably 50,000 or less, more preferably 20,000 or less, and even more preferably 15,000 or less can be easily produced. Therefore, even when producing a large amount of fatty acid-modified unsaturated polyester resin (A) in a factory or the like, the above-mentioned production method eliminates the need to strictly control reaction conditions such as the reaction time of the raw material components, reduces the burden associated with controlling the reaction conditions, and makes it possible to reproducibly produce a fatty acid-modified unsaturated polyester resin (A) having a relatively low weight-average molecular weight.

[0136] <Active energy ray curable monomer (B)> The active energy ray-curable composition contains, in addition to the fatty acid-modified unsaturated polyester resin (A), an active energy ray-curable monomer (B). The active energy ray-curable monomer (B) is a polymerizable functional group-containing compound having one or more polymerizable groups that can be copolymerized with the fatty acid-modified unsaturated polyester resin (A) upon irradiation with active energy rays such as ultraviolet rays.

[0137] The polymerizable group preferably has an ethylenically unsaturated double bond. Examples of the polymerizable group include an acryloyl group, a methacryloyl group, a styryl group, a vinyl group, and an allyl group, with an acryloyl group and a methacryloyl group being preferred. The polymerizable group may be used alone or in combination of two or more types.

[0138] Examples of the active energy ray-curable monomer (B) include polymerizable monofunctional compounds having one polymerizable group per molecule, and photopolymerizable polyfunctional compounds having two or more polymerizable groups per molecule. Hereinafter, examples of the polymerizable monofunctional compounds and photopolymerizable polyfunctional compounds include those having a (meth)acryloyl group. The term "(meth)acryloyl group" refers to an acryloyl group or a methacryloyl group.

[0139] Examples of the polymerizable monofunctional compound include (meth)acrylic acid ester compounds such as 2-hydroxyethyl (meth)acrylate, lauryl (meth)acrylate, stearyl (meth)acrylate, cyclohexyl (meth)acrylate, isooctyl (meth)acrylate, isomyristyl (meth)acrylate, isostearyl (meth)acrylate, isobornyl (meth)acrylate, ethoxydiethylene glycol (meth)acrylate, 2-ethylhexyl-carbitol (meth)acrylate, neopentyl glycol benzoate (meth)acrylate, nonylphenoxypolyethylene glycol (meth)acrylate, epichlorohydrin (ECH)-modified phenoxy (meth)acrylate, phenoxyethyl (meth)acrylate, and paracumylphenol ethylene oxide (EO)-modified (meth)acrylate; vinylpyrrolidone; vinylcaprolactam; and acryloylmorpholine.

[0140] Examples of polymerizable polyfunctional compounds include polymerizable bifunctional compounds having two polymerizable groups in one molecule, polymerizable trifunctional compounds having three polymerizable groups in one molecule, polymerizable tetrafunctional compounds having four polymerizable groups in one molecule, polymerizable pentafunctional compounds having five polymerizable groups in one molecule, and polymerizable hexafunctional compounds having six polymerizable groups in one molecule.

[0141] Examples of the polymerizable bifunctional compound include alkylene glycol di(meth)acrylates such as ethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, and neopentyl glycol di(meth)acrylate; polyalkylene glycol di(meth)acrylates such as diethylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, and tripropylene glycol di(meth)acrylate; 1,4-butanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, dicyclopentadiene di(meth)acrylate, neopentyl glycol adipate di(meth)acrylate, hydroxypivalic acid neopentyl glycol di(meth)acrylate, tricyclodecane dimethanol di(meth)acrylate, and dicyclopentanyl di(meth)acrylate; (meth)acrylic acid ester compounds such as bisphenol A ethylene oxide (EO) addition diacrylate, caprolactone-modified dicyclopentenyl di(meth)acrylate, ethylene oxide-modified phosphate di(meth)acrylate, allylated cyclohexyl di(meth)acrylate, and isocyanurate di(meth)acrylate, or alkylene oxide-modified versions thereof, divinylbenzene, butanediol-1,4-divinyl ether, cyclohexanedimethanol divinyl ether, diethylene glycol divinyl ether, dipropylene glycol divinyl ether, hexanediol divinyl ether, triethylene glycol divinyl ether, phenyl glycidyl ether acrylate hexamethylene diisocyanate urethane prepolymer (trade name "AH-600" manufactured by Kyoeisha Chemical Co., Ltd.), and phenyl glycidyl ether acrylate toluene diisocyanate urethane prepolymer (trade name "AT-600" manufactured by Kyoeisha Chemical Co., Ltd.).

[0142] Examples of the polymerizable trifunctional compound include (meth)acrylic acid ester compounds such as trimethylolpropane tri(meth)acrylate, pentaerythritol tri(meth)acrylate, and tris(acryloxyethyl)isocyanurate, as well as alkylene oxide-modified compounds thereof and tri(meth)acrylates of alkylene oxide-modified isocyanurates.

[0143] Examples of the polymerizable tetrafunctional compound include (meth)acrylic acid ester compounds such as ditrimethylolpropane tetra(meth)acrylate and pentaerythritol tetra(meth)acrylate, and alkylene oxide modified products thereof.

[0144] Examples of the polymerizable pentafunctional compound include (meth)acrylic acid ester compounds such as dipentaerythritol penta(meth)acrylate, and alkylene oxide modified products thereof.

[0145] Examples of polymerizable hexafunctional compounds include (meth)acrylic acid ester compounds such as dipentaerythritol hexa(meth)acrylate, pentaerythritol triacrylate hexamethylene diisocyanate urethane prepolymer (trade name "UA-306H" manufactured by Kyoeisha Chemical Co., Ltd.), and caprolactone-modified dipentaerythritol hexa(meth)acrylate, or alkylene oxide-modified versions thereof.

[0146] The active energy ray-curable monomer (B) may be used alone or in combination of two or more.

[0147] The active energy ray-curable composition is suitably used as an active energy ray-curable ink composition.

[0148] The active energy ray-curable composition can be obtained by mixing, without any particular limitation, the fatty acid-modified unsaturated polyester resin (A) and the active energy ray-curable monomer (B).

[0149] In the active energy ray-curable composition, the content of the fatty acid-modified unsaturated polyester resin (A) is, for example, preferably 15 parts by mass or more, more preferably 25 parts by mass or more, relative to 100 parts by mass of the total amount of the fatty acid-modified unsaturated polyester resin (A) and the active energy ray-curable monomer (B), and is, for example, preferably 80 parts by mass or less, more preferably 75 parts by mass or less.

[0150] In the active energy ray-curable composition, the content of the active energy ray-curable monomer (B) is, for example, preferably 20 parts by mass or more, more preferably 25 parts by mass or more, and for example, preferably 85 parts by mass or less, more preferably 75 parts by mass or less, relative to 100 parts by mass of the total amount of the fatty acid-modified unsaturated polyester resin (A) and the active energy ray-curable monomer (B). The fatty acid-modified unsaturated polyester resin (A) has excellent compatibility with the active energy ray-curable monomer (B). Therefore, the content of the active energy ray-curable monomer (B) can be increased in the active energy ray-curable composition, thereby further improving the abrasion resistance of the coating film.

[0151] Furthermore, the active energy ray-curable composition may contain known additives as needed. Examples of additives include polymerization inhibitors, photopolymerization initiators, fillers, thickeners, foaming agents, antioxidants, light stabilizers, heat stabilizers, and flame retardants. Polymerization inhibitors are preferred. The additives may be used alone or in combination of two or more. The amount and timing of addition of the additives are not particularly limited and are appropriately determined depending on the purpose and application.

[0152] A preferred method for producing the active energy ray-curable composition is to mix the fatty acid-modified unsaturated polyester resin (A), the active energy ray-curable monomer (B), and, if necessary, additives such as a polymerization inhibitor, while heating. This allows the fatty acid-modified unsaturated polyester resin (A) to be dissolved in the active energy ray-curable monomer (B), thereby obtaining the active energy ray-curable composition. The heating temperature is not particularly limited, and is preferably 100 to 240°C.

[0153] The use of the active energy ray-curable composition is not particularly limited. After curing, the active energy ray-curable composition can form a cured film that has excellent adhesion to a substrate and abrasion resistance. Therefore, when no pigment is used, the active energy ray-curable composition can be suitably used as an uncolored varnish or coating agent (coating agent).

[0154] Furthermore, when a pigment is used, the active energy ray-curable composition can also be suitably used as an ink, a paint, or the like. Even when the active energy ray-curable composition is used as an ink or paint containing a pigment, the fatty acid-modified unsaturated polyester resin (A) allows the composition to form a coating film having excellent adhesion and abrasion resistance after curing. Hereinafter, the active energy ray-curable composition and the ink containing a pigment (active energy ray-curable ink) will be described in detail.

[0155] [Active energy ray curable ink] The actinic ray-curable ink contains an actinic ray-curable composition and a pigment.

[0156] The pigment is not particularly limited, and examples thereof include inorganic pigments and organic pigments. The pigments may be used alone or in combination of two or more.

[0157] Examples of inorganic pigments include yellow lead, zinc yellow, iron blue, barium sulfate, cadmium red, titanium oxide, zinc white, red iron oxide, alumina white, calcium carbonate, ultramarine, carbon black, graphite, aluminum powder, red iron oxide, etc. The inorganic pigments may be used alone or in combination of two or more.

[0158] Examples of organic pigments include soluble azo pigments such as β-naphthol pigments, β-oxynaphthoic acid pigments, β-oxynaphthoic acid anilide pigments, acetoacetic acid anilide pigments, and pyrazolone pigments; insoluble azo pigments such as β-naphthol pigments, β-oxynaphthoic acid anilide pigments, acetoacetic acid anilide monoazo pigments, acetoacetic acid anilide disazo pigments, and pyrazolone pigments; copper phthalocyanine blue; and halogenated (chlorinated or brominated) copper phthalocyanine. Examples of organic pigments include phthalocyanine pigments such as nin blue, sulfonated copper phthalocyanine blue, and metal-free phthalocyanine, quinacridone pigments, dioxazine pigments, threne pigments (pyranthrone, anthrone, indanthrone, anthrapyrimidine, flavanthrone, thioindigo, anthraquinone, perinone, and perylene pigments), isoindolinone pigments, metal complex pigments, and polycyclic and heterocyclic pigments such as quinophthalone pigments. The organic pigments may be used alone or in combination of two or more.

[0159] In the active energy ray-curable ink, the content of the active energy ray-curable composition is, for example, preferably 30 parts by mass or more, more preferably 40 parts by mass or more, and for example, preferably 95 parts by mass or less, more preferably 90 parts by mass or less, relative to 100 parts by mass of the total amount of the active energy ray-curable composition and the pigment.

[0160] In the active energy ray-curable ink, the content of the pigment is, for example, preferably 5 parts by mass or more, more preferably 10 parts by mass or more, and for example, preferably 70 parts by mass or less, more preferably 60 parts by mass or less, relative to 100 parts by mass of the total amount of the active energy ray-curable composition and the pigment.

[0161] The actinic ray-curable ink may further contain the actinic ray-curable monomer (B) described above, if necessary, which allows the viscosity of the actinic ray-curable ink to be adjusted depending on the intended use, such as the printing method.

[0162] The amount of the active energy ray-curable monomer blended when preparing the active energy ray-curable ink is, relative to 100 parts by mass of the total amount of the active energy ray-curable composition (varnish) and pigment, for example, 3 parts by mass or more, preferably 5 parts by mass or more, and for example, 45 parts by mass or less, preferably 35 parts by mass or less.

[0163] The active energy ray-curable ink may further contain a photopolymerization initiator, if necessary.

[0164] The photopolymerization initiator is not particularly limited, and examples thereof include 2,2-dimethoxy-1,2-diphenylethan-1-one, 1-hydroxycyclohexyl phenyl ketone, 1-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-methyl-1-(4-methylthiophenyl)-2-morpholinopropan-1-one, and 2-methyl-1-(4-methylthiophenyl)-2-morpholinopropan-1-one. -one, 2-benzyl-2-dimethylamino-1-(4-morpholinophenyl)-butanone-1, bis(2,4,6-trimethylbenzoyl)-phenylphosphine oxide, 2,4,6-trimethylbenzoyl-diphenyl-phosphine oxide, 4-methylbenzophenone, benzophenone, 2-hydroxy-1-{4-[4-(2-hydroxy-2-methylpropionyl)-benzyl]phenyl}-2-methyl-propan-1-one, etc. The photopolymerization initiator may be used alone or in combination of two or more.

[0165] In the active energy ray-curable ink, the content of the photopolymerization initiator is, for example, preferably 0.5 parts by mass or more, more preferably 1.0 part by mass or more, and for example, preferably 20 parts by mass or less, more preferably 15 parts by mass or less, relative to 100 parts by mass of the total amount of the active energy ray-curable composition (varnish) and pigment.

[0166] The active energy ray-curable ink may contain other additives as required.

[0167] Examples of additives include curing accelerators (such as cobalt naphthenate), and the same additives as those described above in the active energy ray-curable composition (such as fillers, thickeners, foaming agents, antioxidants, light stabilizers, heat stabilizers, and flame retardants).The additives may be used alone or in combination of two or more.The amount and timing of addition of the additives are not particularly limited and are appropriately determined depending on the purpose and application.

[0168] The active energy ray-curable ink can be produced, for example, by kneading the active energy ray-curable composition, the pigment, and, if necessary, the active energy ray-curable monomer (B), the photopolymerization initiator, and other additives. The kneading can be carried out using known means such as a bead mill, a roll mill, a ball mill, an attritor, or a sand mill.

[0169] The above-mentioned active energy ray-curable composition (varnish) and active energy ray-curable ink contain an active energy ray-curable composition, and therefore have excellent solubility and anti-misting properties.

[0170] Therefore, the active energy ray-curable composition (varnish) and the active energy ray-curable ink can be printed using various printing methods.

[0171] More specifically, in printing, an active energy ray-curable composition or an active energy ray-curable ink is applied to a substrate by a known method, and then cured by irradiation with active energy rays. This results in an article having a substrate and a coating film made of a cured product of the active energy ray-curable composition or the active energy ray-curable ink. That is, when the active energy ray-curable ink is applied to a substrate, a printed layer printed using the active energy ray-curable ink is formed on the substrate.

[0172] The substrate is not particularly limited, and examples thereof include uncoated paper such as fine paper; coated paper such as lightly coated paper, art paper, coated paper, lightweight coated paper, and cast coated paper; paperboard such as white paperboard and cardboard; synthetic paper, aluminum-deposited paper, and plastic film.

[0173] Generally, active energy ray-curable compositions and active energy ray-curable inks have difficulty penetrating into plastic films and tend to have poor adhesion to substrates such as paper. In particular, plastic films containing resins such as polypropylene and polyethylene have low polarity, which can further reduce the adhesion of the active energy ray-curable compositions and active energy ray-curable inks. However, in the present invention, by using the fatty acid-modified unsaturated polyester resin (A) described above, the active energy ray-curable compositions and active energy ray-curable inks have appropriate fluidity and excellent wettability to substrates, thereby enabling them to exhibit high adhesion not only to substrates such as paper but also to plastic films. Therefore, plastic films are preferably used as substrates because they can particularly exhibit the effects of the present invention.

[0174] Examples of plastics that can be used to form plastic films include olefin-based resins such as polyethylene and polypropylene; ester-based resins such as polyethylene terephthalate, polycarbonate, and polylactic acid; styrene-based resins such as polystyrene, AS resin, and ABS resin; nylon, polyamide, polyvinyl chloride, and polyvinylidene chloride. Among these, olefin-based resins are preferred, with polyethylene and polypropylene being more preferred. Olefin-based resins tend to have poor adhesion due to their low polarity, but the active energy ray-curable composition and active energy ray-curable ink of the present invention can exhibit high adhesion even to plastic films containing such olefin resins.

[0175] The application method is not particularly limited, and known printing methods such as screen printing, offset printing, flexographic printing, and roll printing can be used.

[0176] While active energy ray-curable compositions and active energy ray-curable inks are sometimes required to have high viscosities in offset printing, they are sometimes required to have low viscosities in flexographic printing. Because the fatty acid-modified unsaturated polyester resin (A) has excellent compatibility with the active energy ray-curable monomer (B), the mixing ratio of the fatty acid-modified unsaturated polyester resin (A) to the active energy ray-curable monomer (B) can be adjusted over a wide range. By adjusting this mixing ratio, the viscosity of the active energy ray-curable composition or active energy ray-curable ink can be easily adjusted to a desired range. Therefore, it is easy to adjust the viscosity to the required level depending on the application, and the active energy ray-curable composition or active energy ray-curable ink can be used in a variety of printing methods.

[0177] Examples of active energy rays include ultraviolet rays and electron beams.

[0178] When curing with ultraviolet light, an ultraviolet irradiation device having a light source such as a xenon lamp, a high-pressure mercury lamp, or a metal halide lamp is used. The amount of ultraviolet light irradiation, the amount of light from the ultraviolet irradiation device, and the location of the light source are appropriately adjusted as necessary. Specifically, when a high-pressure mercury lamp is used, for example, a substrate coated with an active energy ray-curable composition or an active energy ray-curable ink is irradiated with a light intensity of 80 to 1000 W / cm. 2 For one lamp, the substrate is conveyed at a conveying speed of 5 to 50 m / min. When curing is performed with an electron beam, the substrate coated with the active energy ray-curable composition or active energy ray-curable ink is conveyed at a conveying speed of 5 to 50 m / min, for example, by an electron beam accelerator having an acceleration voltage of 10 to 300 kV.

[0179] The active energy ray-curable composition or the active energy ray-curable ink is crosslinked and cured by irradiation with ultraviolet rays, i.e., active energy rays, resulting in a cured film being obtained on the substrate as a cured product of the active energy ray-curable composition or the active energy ray-curable ink.

[0180] The active energy ray-curable composition or the active energy ray-curable ink is suitably used in printing methods such as lithographic printing, letterpress printing, intaglio printing, and stencil printing to obtain various printed materials, such as printed materials for forms, printed materials for various packaging such as carton paper, printed materials for various plastics, printed materials for seals and labels, artistic printed materials, and printed materials for metals.

[0181] The active energy ray-curable composition can also be used as a coating agent (coating agent). When the active energy ray-curable composition is used as a coating agent, the coating agent may contain a photopolymerization initiator and other additives. Note that the explanation of the photopolymerization initiator and other additives is the same as that for the active energy ray-curable ink described above, and therefore will not be given here. Then, the coating agent is applied to a substrate in the same manner as above, and then irradiated with active energy rays to cause curing, thereby forming a coating layer made of a cured product of the coating agent on the substrate.

[0182] Furthermore, the active energy ray-curable composition can also be used as an active energy ray-curable paint. The active energy ray-curable paint contains the active energy ray-curable composition and a pigment. The active energy ray-curable paint may also contain a photopolymerization initiator and other additives. Note that the explanations regarding the pigment, photopolymerization initiator, and other additives are the same as those for the active energy ray-curable ink described above, and therefore detailed explanations will be omitted here. Then, the active energy ray-curable paint is applied to a substrate in the same manner as above, and then irradiated with active energy rays to cause curing, thereby forming a coating layer consisting of a cured product of the active energy ray-curable paint on the substrate. [Example]

[0183] Next, the present invention will be described based on examples and comparative examples, but the present invention is not limited to the following examples. Note that "parts" and "%" are by mass unless otherwise specified. Furthermore, specific numerical values ​​such as blending ratios (content ratios), physical property values, and parameters used in the following description can be substituted with the corresponding upper limit values ​​(numeric values ​​defined as "equal to or less than") or lower limit values ​​(numeric values ​​defined as "equal to or more than" or "exceeding") of the blending ratios (content ratios), physical property values, parameters, etc. described in the above "Modes for Carrying Out the Invention."

[0184] <Example 1: Synthesis of fatty acid modified unsaturated polyester resin 1> A reactor equipped with a stirrer, reflux condenser, nitrogen gas inlet, and thermometer was charged with 30.8 parts by mass of lauric acid (iodine value 1 or less), 10.1 parts by mass of isophthalic acid, and 13.8 parts by mass of glycerin. The temperature was raised to 230°C while blowing in nitrogen gas, and the reaction was continued until the acid value reached 10 mgKOH / g or less, resulting in a direct esterification reaction (first esterification step). The reactor was then cooled to 200°C, and 27.8 parts by mass of maleic anhydride, 17.5 parts by mass of 1,3-propanediol, and 0.1 parts by mass of t-butylhydroquinone (TBHQ) were added. The direct esterification reaction was continued until the acid value reached 20 mgKOH / g (second esterification step). This yielded fatty acid-modified unsaturated polyester resin 1. The methanol tolerance of fatty acid-modified unsaturated polyester resin 1 at 25°C was 55 g. The weight average molecular weight of the fatty acid-modified unsaturated polyester resin 1 was measured according to the procedure described above, and the measurement results are shown in Table 1.

[0185] <Example 2: Synthesis of fatty acid modified unsaturated polyester resin 2> A reaction vessel equipped with a stirrer, reflux condenser, nitrogen gas inlet, and thermometer was charged with 37.4 parts by mass of lauric acid, 5.2 parts by mass of tetrahydrophthalic anhydride, 5.2 parts by mass of benzoic acid, and 14.9 parts by mass of glycerin. The temperature was raised to 230°C while blowing in nitrogen gas, and the reaction was continued until the acid value reached 10 mgKOH / g or less, resulting in a direct esterification reaction (first esterification step). The reaction vessel was then cooled to 200°C, and 23.9 parts by mass of maleic anhydride, 13.4 parts by mass of 1,3-propanediol, and 0.1 parts by mass of TBHQ were added. The direct esterification reaction was continued until the acid value reached 21 mgKOH / g (second esterification step). This resulted in the production of fatty acid-modified unsaturated polyester resin 2. The methanol tolerance of fatty acid-modified unsaturated polyester resin 2 at 25°C was 93 g. The weight-average molecular weight of fatty acid-modified unsaturated polyester resin 2 was measured according to the procedure described above, and the results are shown in Table 1.

[0186] <Example 3: Synthesis of fatty acid modified unsaturated polyester resin 3> A reactor equipped with a stirrer, reflux condenser, nitrogen gas inlet, and thermometer was charged with 34.6 parts by weight of coconut oil (iodine value 9) and 7 parts by weight of pentaerythritol, and the transesterification reaction was carried out at 250°C for 6 hours (transesterification step). The reactor was then cooled to 200°C, and 10.3 parts by weight of benzoic acid and 5.8 parts by weight of tetrahydrophthalic anhydride were added. The temperature was raised to 230°C while blowing in nitrogen gas, and the reaction was continued until the acid value reached 10 mgKOH / g or less, resulting in a direct esterification reaction (first esterification step). The reactor was then cooled to 200°C, and 24.3 parts by weight of maleic anhydride, 18 parts by weight of 1,3-propanediol, and 0.1 parts by weight of TBHQ were added. The direct esterification reaction was carried out until the acid value reached 22 mgKOH / g (second esterification step). This produced fatty acid-modified unsaturated polyester resin 3. The methanol tolerance of the fatty acid-modified unsaturated polyester resin 3 at 25° C. was 93 g. The weight average molecular weight of the fatty acid-modified unsaturated polyester resin 3 was measured according to the procedure described above, and the measurement results are shown in Table 1.

[0187] Example 4: Synthesis of fatty acid modified unsaturated polyester resin 4 A reactor equipped with a stirrer, reflux condenser, nitrogen gas inlet, and thermometer was charged with 25.1 parts by weight of stearic acid (iodine value 1 or less), 25.1 parts by weight of disproportionated rosin, 3.1 parts by weight of tetrahydrophthalic anhydride, and 11.8 parts by weight of glycerin. The temperature was raised to 240°C while blowing in nitrogen gas, and the reaction was continued until the acid value reached 10 mgKOH / g or less, resulting in a direct esterification reaction (first esterification step). The reactor was then cooled to 200°C, and 22.4 parts by weight of maleic anhydride, 12.5 parts by weight of 1,3-propanediol, and 0.1 parts by weight of TBHQ were added. The direct esterification reaction was continued until the acid value reached 15 mgKOH / g (second esterification step). This resulted in fatty acid-modified unsaturated polyester resin 4. The methanol tolerance of fatty acid-modified unsaturated polyester resin 4 at 25°C was 44 g. The weight average molecular weight of the fatty acid-modified unsaturated polyester resin 4 was measured according to the procedure described above, and the measurement results are shown in Table 1.

[0188] <Example 5: Synthesis of fatty acid modified unsaturated polyester resin 5> A reaction vessel equipped with a stirrer, reflux condenser, nitrogen gas inlet, and thermometer was charged with 25.1 parts by mass of lauric acid, 25.1 parts by mass of disproportionated rosin, 3.1 parts by mass of tetrahydrophthalic anhydride, and 11.8 parts by mass of glycerin. The temperature was raised to 240°C while blowing in nitrogen gas, and the reaction was continued until the acid value reached 10 mgKOH / g or less, resulting in a direct esterification reaction (first esterification step). The reaction vessel was then cooled to 200°C, and 22.4 parts by mass of maleic anhydride, 12.5 parts by mass of 1,3-propanediol, and 0.1 parts by mass of TBHQ were added. The direct esterification reaction was continued until the acid value reached 19 mgKOH / g (second esterification step). This resulted in the production of fatty acid-modified unsaturated polyester resin 5. The methanol tolerance of fatty acid-modified unsaturated polyester resin 5 at 25°C was 58 g. The weight-average molecular weight of fatty acid-modified unsaturated polyester resin 5 was measured according to the procedure described above, and the results are shown in Table 1.

[0189] <Example 6: Synthesis of fatty acid modified unsaturated polyester resin 6> A reaction vessel equipped with a stirrer, reflux condenser, nitrogen gas inlet, and thermometer was charged with 25.1 parts by mass of lauric acid, 25.1 parts by mass of disproportionated rosin, 3.1 parts by mass of tetrahydrophthalic anhydride, and 11.8 parts by mass of glycerin. The temperature was raised to 240°C while blowing in nitrogen gas, and the reaction was continued until the acid value reached 10 mgKOH / g or less, resulting in a direct esterification reaction (first esterification step). The reaction vessel was then cooled to 230°C, and 22.4 parts by mass of maleic anhydride, 12.5 parts by mass of 1,3-propanediol, and 0.1 parts by mass of TBHQ were added. The direct esterification reaction was continued until the acid value reached 21 mgKOH / g (second esterification step). This resulted in the production of fatty acid-modified unsaturated polyester resin 6. The methanol tolerance of fatty acid-modified unsaturated polyester resin 6 at 25°C was 42 g. The weight-average molecular weight of fatty acid-modified unsaturated polyester resin 6 was measured according to the procedure described above, and the results are shown in Table 1.

[0190] <Example 7: Synthesis of fatty acid modified unsaturated polyester resin 7> A reaction vessel equipped with a stirrer, reflux condenser, nitrogen gas inlet, and thermometer was charged with 25.1 parts by mass of lauric acid, 25.1 parts by mass of gum rosin, 3.1 parts by mass of tetrahydrophthalic anhydride, and 9.5 parts by mass of glycerin. The temperature was raised to 240°C while blowing in nitrogen gas, and the reaction was continued until the acid value reached 10 mgKOH / g or less, resulting in a direct esterification reaction (first esterification step). The reaction vessel was then cooled to 200°C, and 22.4 parts by mass of maleic anhydride, 14.8 parts by mass of 1,3-propanediol, and 0.1 parts by mass of TBHQ were added. The direct esterification reaction was continued until the acid value reached 25 mgKOH / g (second esterification step). This resulted in fatty acid-modified unsaturated polyester resin 7. The methanol tolerance of fatty acid-modified unsaturated polyester resin 7 at 25°C was 40 g. The weight-average molecular weight of fatty acid-modified unsaturated polyester resin 7 was measured according to the procedure described above, and the results are shown in Table 1.

[0191] <Example 8: Synthesis of fatty acid modified unsaturated polyester resin 8> A reactor equipped with a stirrer, reflux condenser, nitrogen gas inlet, and thermometer was charged with 5.2 parts by weight of lauric acid, 41 parts by weight of disproportionated rosin, 5 parts by weight of tetrahydrophthalic anhydride, 5 parts by weight of benzoic acid, and 11.4 parts by weight of glycerin. The temperature was raised to 240°C while blowing in nitrogen gas, and the reaction was continued until the acid value reached 10 mgKOH / g or less, resulting in a direct esterification reaction (first esterification step). The reactor was then cooled to 200°C, and 20.1 parts by weight of maleic anhydride, 12.3 parts by weight of 1,3-propanediol, and 0.1 parts by weight of TBHQ were added. The direct esterification reaction was continued until the acid value reached 23 mgKOH / g (second esterification step). This resulted in a fatty acid-modified unsaturated polyester resin 8. The methanol tolerance of the fatty acid-modified unsaturated polyester resin 8 at 25°C was 80 g. The weight average molecular weight of the fatty acid-modified unsaturated polyester resin 8 was measured according to the procedure described above, and the measurement results are shown in Table 1.

[0192] Example 9: Synthesis of fatty acid-modified unsaturated polyester resin 9 A reaction vessel equipped with a stirrer, reflux condenser, nitrogen gas inlet, and thermometer was charged with 24.8 parts by mass of lauric acid, 6.5 parts by mass of tetrahydrophthalic anhydride, 8 parts by mass of benzoic acid, and 16 parts by mass of glycerin. The temperature was raised to 250°C while blowing in nitrogen gas, and the reaction was continued until the acid value reached 10 mgKOH / g or less, resulting in a direct esterification reaction (first esterification step). The reaction vessel was then cooled to 200°C, and 25 parts by mass of maleic anhydride, 19.7 parts by mass of 1,3-propanediol, and 0.1 parts by mass of TBHQ were added. The direct esterification reaction was continued until the acid value reached 18 mgKOH / g (second esterification step). This resulted in fatty acid-modified unsaturated polyester resin 9. The methanol tolerance of fatty acid-modified unsaturated polyester resin 9 at 25°C was 135 g. The weight-average molecular weight of fatty acid-modified unsaturated polyester resin 9 was measured according to the procedure described above, and the results are shown in Table 1.

[0193] Example 10: Synthesis of fatty acid modified unsaturated polyester resin 10 A reaction vessel equipped with a stirrer, reflux condenser, nitrogen gas inlet, and thermometer was charged with 32.8 parts by mass of lauric acid, 21.8 parts by mass of adipic acid, 12.8 parts by mass of isophthalic acid, and 13.3 parts by mass of glycerin. The temperature was raised to 230°C while blowing in nitrogen gas, and the reaction was continued until the acid value reached 10 mgKOH / g or less, resulting in a direct esterification reaction (first esterification step). The reaction vessel was then cooled to 200°C, and 6 parts by mass of maleic anhydride, 13.3 parts by mass of 1,3-propanediol, and 0.1 parts by mass of TBHQ were added. The direct esterification reaction was continued until the acid value reached 17 mgKOH / g (second esterification step). This resulted in a fatty acid-modified unsaturated polyester resin 10. The methanol tolerance of the fatty acid-modified unsaturated polyester resin 10 at 25°C was 92 g. The weight-average molecular weight of the fatty acid-modified unsaturated polyester resin 10 was measured according to the procedure described above, and the results are shown in Table 1.

[0194] Comparative Example 1: Synthesis of fatty acid-modified unsaturated polyester resin 11 A reaction vessel equipped with a stirrer, reflux condenser, nitrogen gas inlet, and thermometer was charged with 49.2 parts by mass of disproportionated rosin, 5 parts by mass of tetrahydrophthalic anhydride, 5 parts by mass of benzoic acid, and 11.4 parts by mass of glycerin. The temperature was raised to 250°C while blowing in nitrogen gas, and the reaction was continued until the acid value reached 10 mgKOH / g or less, resulting in a direct esterification reaction (first esterification step). The reaction vessel was then cooled to 200°C, and 18.5 parts by mass of maleic anhydride, 10.9 parts by mass of 1,3-propanediol, and 0.1 parts by mass of TBHQ were added. The direct esterification reaction was continued until the acid value reached 15 mgKOH / g (second esterification step). This yielded fatty acid-modified unsaturated polyester resin 11. The methanol tolerance of fatty acid-modified unsaturated polyester resin 11 at 25°C was 58 g. The weight-average molecular weight of fatty acid-modified unsaturated polyester resin 11 was measured according to the procedure described above, and the results are shown in Table 1.

[0195] Comparative Example 2: Synthesis of fatty acid-modified unsaturated polyester resin 12 A reaction vessel equipped with a stirrer, reflux condenser, nitrogen gas inlet, and thermometer was charged with 32.8 parts by mass of lauric acid, 12.8 parts by mass of isophthalic acid, and 10.3 parts by mass of glycerin. The temperature was raised to 230°C while blowing in nitrogen gas, and the reaction was continued until the acid value reached 10 mgKOH / g or less, resulting in a direct esterification reaction (first esterification step). The reaction vessel was then cooled to 200°C, and 27.8 parts by mass of adipic acid, 16.3 parts by mass of 1,3-propanediol, and 0.1 parts by mass of TBHQ were added. The direct esterification reaction was continued until the acid value reached 20 mgKOH / g (second esterification step). This resulted in the production of fatty acid-modified unsaturated polyester resin 12. The methanol tolerance of fatty acid-modified unsaturated polyester resin 12 at 25°C was 58 g. The weight-average molecular weight of fatty acid-modified unsaturated polyester resin 12 was measured according to the procedure described above, and the results are shown in Table 1.

[0196] Example 1 60 parts by mass of the obtained fatty acid-modified unsaturated polyester resin 1, 20 parts by mass of EO-modified trimethylolpropane triacrylate (EO-modified TMPTA), 20 parts by mass of hexanediol diacrylate (HDDA), and 0.1 parts by mass of hydroquinone (HQ) were mixed and heated to approximately 110°C to dissolve, thereby obtaining active energy ray-curable ink composition 1 (hereinafter referred to as varnish 1).

[0197] Next, 50 parts by weight of the obtained varnish 1, 20 parts by weight of neutral carbon black (CB, pigment, manufactured by Mitsubishi Chemical Corporation under the trade name "RCF#52"), 25 parts by weight of hexanediol diacrylate (HDDA), and 5 parts by weight of a photopolymerization initiator (2-methyl-1-[4-(methylthio)phenyl]-2-morpholinopropan-1-one, manufactured by BASF Japan under the trade name "Irgacure 907") were blended and milled in a three-roll mill (manufactured by Inoue Seisakusho Co., Ltd., S-4 3 / 4 x 11) to disperse the pigment so that the maximum particle size was 7.5 μm or less. This produced active energy ray-curable ink 1 (hereinafter referred to as ink 1).

[0198] (Examples 2 to 10 and Comparative Examples 1 and 2) Actinic ray-curable ink compositions 2 to 12 (hereinafter referred to as "varnishes 2 to 12," respectively) were obtained in the same manner as in Example 1, except that fatty acid-modified unsaturated polyester resins 2 to 12 were used instead of fatty acid-modified unsaturated polyester resin 1. Furthermore, active energy ray-curable inks 2 to 12 (hereinafter referred to as "inks 2 to 12", respectively) were obtained in the same manner as in Example 1, except that varnish 1 was replaced with varnishes 2 to 12, respectively.

[0199] Tables 1 to 3 show the raw material components used in the synthesis of the above-mentioned fatty acid-modified unsaturated polyester resin, and the amounts of each component used in the production of the actinic ray-curable ink composition (also simply referred to as "varnish") and actinic ray-curable ink (also simply referred to as "ink"). In Tables 1 and 2, fatty acid-modified unsaturated polyester resins 1 to 12 are simply referred to as "resins 1 to 12," respectively. In the raw material components of fatty acid-modified unsaturated polyester resins 1 to 12, the molar equivalent ratio of hydroxyl groups contained in the polyhydric alcohol to 1 molar equivalent of carboxyl groups contained in the raw material components is shown in the "molar equivalent ratio [OH / COOH]" column in Table 1.

[0200] In addition, for fatty acid modified unsaturated polyester resins 1 to 12, the 5 The state (liquid or solid) of the compound under 1 atm of pressure is shown in Table 1. 5 At 1 Pa (1 atm), the fatty acid modified unsaturated polyester resin 8 was in a solid state with a softening point of 65°C, and the fatty acid modified unsaturated polyester resin 11 was in a solid state with a softening point of 79°C.

[0201] (evaluation) The inks obtained in the examples and comparative examples were evaluated by the following methods. The results are shown in Table 1.

[0202] (Adhesion evaluation) 0.5 mL of ink was applied to a polypropylene sheet (manufactured by Okamoto Corporation, product name "Clear C") using a full-surface RI tester roll. Then, using an ultraviolet irradiation device (manufactured by Eye Graphics Co., Ltd., product name "ESC-4011GX"), a metal halide lamp of 80 W / cm was used. 2 The ink spread on the polypropylene sheet was cured by irradiating it with ultraviolet light at a conveyor speed of 50 m / min, to obtain a printed layer.

[0203] The adhesion of the printed layer was evaluated according to the cross-cut method of JIS K5600-5-6 (1999). Specifically, a grid-like pattern of 100 squares was first cut into the printed layer at 1 mm intervals. Next, adhesive tape was applied evenly to the printed layer and then peeled off, and the remaining rate [%] of the printed layer (the ratio of the number of remaining squares out of 100) was evaluated according to the following evaluation criteria. Note that if the remaining rate was 70% or more, i.e., the following evaluation criteria was 3 or more, it was determined to be practical. <Evaluation criteria> 5: The survival rate was 90% or more. 4: The survival rate was 80% or more but less than 90%. 3: The survival rate was 70% or more but less than 80%. 2: The survival rate was 60% or more but less than 70%. 1: The survival rate was 60% or less.

[0204] (Abrasion resistance evaluation) The ink was applied to art paper in an amount of 0.25 mL using an RI tester (manufactured by Tester Sangyo Co., Ltd.). Then, using an ultraviolet irradiation device (manufactured by Eye Graphics Co., Ltd., product name "ESC-4011GX"), the ink was applied to art paper in an amount of 0.25 mL using a metal halide lamp at 80 W / cm. 2 The ink spread on the art paper was cured by irradiating it with ultraviolet light at a conveyor speed of 50 m / min to form a printed layer, and a test piece was obtained.

[0205] A rub resistance test was conducted using a test piece using a Gakushin-type rub fastness tester (manufactured by Tester Sangyo Co., Ltd., 500g load, 50 times, paper: wood-free paper), and scratches on the ink-covered surface of the test piece, i.e., the surface of the printed layer, were evaluated based on the following evaluation criteria. A score of 3 or higher on the following criteria is considered to be at a level that is acceptable for practical use. <Evaluation criteria> 5: No scratches at all 4: The area of ​​the wound is less than 10% 3: The area of ​​the scratch is 10% or more but less than 30% 2: The area of ​​the scratch is 30% or more but less than 50% 1: The area of ​​the wound is 50% or more

[0206] [Table 1]

[0207] [Table 2]

[0208] [Table 3]

[0209] The active energy ray-curable composition of the present invention, by using the fatty acid-modified unsaturated polyester resin (A), can form a coating film that has excellent adhesion to a substrate and excellent abrasion resistance. The examples demonstrate that such effects can be similarly exhibited even when the active energy ray-curable composition is used as an ink containing the composition together with a pigment (active energy ray-curable ink), but it can also be said that the active energy ray-curable composition of the present invention can exhibit the above effects even if it does not contain a pigment. [Industrial Applicability]

[0210] According to the present invention, by using a fatty acid-modified unsaturated polyester resin (A), it is possible to provide an active energy ray-curable composition capable of forming a coating film that has excellent adhesion to a substrate and abrasion resistance.

Claims

1. An active energy ray-curable composition containing a fatty acid-modified unsaturated polyester resin (A) and an active energy ray-curable monomer (B), The active energy ray-curable composition is characterized in that the fatty acid-modified unsaturated polyester resin (A) is a reaction product of raw material components including at least one of fatty acids and fats and oils, an α,β-unsaturated dicarboxylic acid as an acid component, and a polyhydric alcohol.

2. 2. The active energy ray-curable composition according to claim 1, wherein the raw material components further contain rosins as an acid component.

3. 3. The active energy ray-curable composition according to claim 2, wherein the rosin is at least one selected from the group consisting of disproportionated rosin, hydrogenated rosin, and polymerized rosin.

4. The active energy ray-curable composition according to claim 2 or 3, characterized in that, in producing the fatty acid-modified unsaturated polyester resin (A), the esterification reaction temperature after adding the α,β-unsaturated dicarboxylic acid is 230°C or lower.

5. 2. The active energy ray-curable composition according to claim 1, wherein the fatty acid-modified unsaturated polyester resin (A) has a methanol tolerance of 120 g or less.

6. An active energy ray-curable ink comprising the active energy ray-curable composition according to claim 1 and a pigment.

7. An active energy ray-curable coating material comprising the active energy ray-curable composition according to claim 1 and a pigment.

8. An article comprising a printed layer printed using the active energy ray-curable ink according to claim 6.

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