Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B05—SPRAYING OR ATOMISING IN GENERAL; APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
  • B05D—PROCESSES FOR APPLYING FLUENT MATERIALS TO SURFACES, IN GENERAL
  • B05D7/00—Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying particular liquids or other fluent materials
  • B05D7/24—Processes, other than flocking, specially adapted for applying liquids or other fluent materials to particular surfaces or for applying particular liquids or other fluent materials for applying particular liquids or other fluent materials
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B27/00—Layered products comprising a layer of synthetic resin
  • B32B27/16—Layered products comprising a layer of synthetic resin specially treated, e.g. irradiated
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B32—LAYERED PRODUCTS
  • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
  • B32B27/00—Layered products comprising a layer of synthetic resin
  • B32B27/30—Layered products comprising a layer of synthetic resin comprising vinyl (co)polymers; comprising acrylic (co)polymers
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41M—PRINTING, DUPLICATING, MARKING, OR COPYING PROCESSES; COLOUR PRINTING
  • B41M1/00—Inking and printing with a printer's forme
  • B41M1/26—Printing on other surfaces than ordinary paper
  • B41M1/30—Printing on other surfaces than ordinary paper on organic plastics, horn or similar materials
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41M—PRINTING, DUPLICATING, MARKING, OR COPYING PROCESSES; COLOUR PRINTING
  • B41M3/00—Printing processes to produce particular kinds of printed work, e.g. patterns
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
  • C08F283/00—Macromolecular compounds obtained by polymerising monomers on to polymers provided for in subclass C08G
• • C—CHEMISTRY; METALLURGY
  • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
  • C08F—MACROMOLECULAR COMPOUNDS OBTAINED BY REACTIONS ONLY INVOLVING CARBON-TO-CARBON UNSATURATED BONDS
  • C08F290/00—Macromolecular compounds obtained by polymerising monomers on to polymers modified by introduction of aliphatic unsaturated end or side groups
  • C08F290/02—Macromolecular compounds obtained by polymerising monomers on to polymers modified by introduction of aliphatic unsaturated end or side groups on to polymers modified by introduction of unsaturated end groups
  • C08F290/06—Polymers provided for in subclass C08G
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
  • C09D11/00—Inks
  • C09D11/02—Printing inks
  • C09D11/10—Printing inks based on artificial resins
  • C09D11/101—Inks specially adapted for printing processes involving curing by wave energy or particle radiation, e.g. with UV-curing following the printing

Definitions

• Embodiments of the present invention relate to electron beam curable compositions and laminates.
• Active energy ray curing technology shortens process time through instant drying, reduces environmental impact and improves work safety by being non-volatile (non-VOC), and achieves strong coating film properties through crosslinking reactions.
• active energy ray curing technology began in the commercial printing field, which uses paper substrates such as flyers and posters, and has expanded to various fields due to the development of printing technology, including printing machines and printing inks.
• active energy ray curing technology is expanding to fields that use various film substrates.
• its use as a packaging material for packaged products such as packaging for food, cosmetics, and toys is expanding.
• Active energy ray-curable compositions are broadly divided into ultraviolet ray-curable compositions and electron beam-curable compositions from the viewpoint of reaction form.
• ultraviolet ray-curable compositions require a photopolymerization initiator, and are prone to migration problems due to the low molecular weight photopolymerization initiator.
• electron beam-curable compositions do not require a photopolymerization initiator because they use high-energy electron beams. Therefore, from the viewpoint of improving migration problems, it is considered that electron beam-curable compositions can be preferably used in applications such as food packaging materials.
• typical electron beam curable compositions like UV curable compositions, contain (meth)acrylate monomers as the main binder component, and are prone to migration problems due to low molecular weight (meth)acrylate monomers. Therefore, even when electron beam curable compositions are used as inks, further investigation is required to improve migration.
• a related problem is that when packaging materials have a printed surface after being printed with active energy ray-curable ink, the printed surface of the packaging material can become scratched or peeled off due to vibrations and friction that occur during transportation on trucks, etc., and a solution to this problem is desired.
• Lithographic printing includes wet lithographic printing, which uses dampening water to form an image by the repulsion of oil (ink) in the printing areas and water (dampening water) in the non-printing areas, and waterless lithographic printing, which uses a silicone layer in the non-printing areas to form an image by the repulsion of the ink in the printing areas.
• wet lithographic printing which has good workability, is preferably used.
• Patent Document 1 discloses a urethane resin that uses an alkyl monoalcohol compound, a polyol compound, and a polyisocyanate compound as essential reactive raw materials as a binder resin.
• a composition that combines the disclosed binder resin with a (meth)acrylate monomer and a photopolymerization initiator tends to have insufficient adhesion to a film substrate.
• Patent Document 2 discloses an electron beam curable composition containing, as essential components, a rosin-modified resin, a (meth)acrylate compound, and an extender pigment.
• the disclosed electron beam curable composition is expected to improve printability, but it does not have sufficient resistance to scratches and peeling caused by vibration and friction during transportation.
• Patent Document 3 discloses an electron beam curable composition whose essential components are an acrylate monomer, an acrylate oligomer, an inactive resin, an acrylated epoxidized vegetable oil, and a white pigment.
• the disclosed electron beam curable composition has a configuration developed for use as a primer. Therefore, particularly when used in wet lithographic printing, the emulsification balance with the dampening water is poor, and since the binder resin needs to be made into a low molecular weight resin, the viscoelasticity required for the ink cannot be obtained, making it difficult to obtain high-quality printed matter stably over a long period of time.
• Patent Document 4 discloses an active energy ray-curable resin composition
• the disclosed active energy ray-curable resin composition uses a low molecular weight (meth)acrylate compound as the (meth)acrylate compound other than the urethane (meth)acrylate resin. Therefore, when the composition is used as a printing ink, there is a concern that the curing and migration properties during high-speed printing may be deteriorated. In addition, there is a tendency for the stability on the press and the stability during emulsification during water-based lithographic printing to deteriorate.
• JP 2019-183012 A JP 2023-028276 A International Publication No. 2020/212488 International Publication No. 2020/209264
• One embodiment of the present invention provides an electron beam curable composition that has safety, such as low migration properties, and can be used as a packaging material for various packages, and can form a film that has both excellent adhesion to the film substrate and film strength, thereby reducing problems such as abrasion or peeling during transportation and having good printability.
• Another embodiment of the present invention provides a laminate that uses the electron beam curable composition of the above embodiment.
• An electron beam curable composition comprising a resin (A) having a weight average molecular weight of 5,000 to 50,000, a (meth)acrylate compound (B) having a weight average molecular weight of 700 to 3,000 and a weight average molecular weight per (meth)acryloyl group of 100 to 300, and a pigment (C).
• the resin (A) includes at least one resin selected from the group consisting of rosin-modified resins and urethane (meth)acrylate resins.
• ⁇ 6> The electron beam curable composition according to any one of ⁇ 1> to ⁇ 5> above, in which the total content of the resin (A), the (meth)acrylate compound (B), and the pigment (C) is 60 to 90 mass% based on the total mass of the composition.
• ⁇ 9> A laminate having a substrate and a cured product of the electron beam curable composition described in any one of ⁇ 1> to ⁇ 9> above.
• a method for producing the laminate comprising: applying the electron beam curable composition according to any one of ⁇ 1> to ⁇ 9> above onto a substrate to form a coating film; and irradiating the coating film with an electron beam under conditions of an acceleration voltage of 40 to 120 kV and an exposure dose of 10 to 60 kGy.
• the disclosure of this application is related to the subject matter described in Japanese Patent Application No. 2023-111823, filed on July 7, 2023, the entire disclosure of which is incorporated herein by reference.
• an electron beam curable composition that has safety, such as low migration properties, and can be used as a packaging material for various packages, and that can form a coating film that combines excellent adhesion to film substrates and film strength, thereby reducing problems such as abrasion or peeling during transportation and having good printability. It is also possible to provide a laminate that uses the electron beam curable composition of the above embodiment.
• conjugated double bond refers to a bond in which multiple double bonds are alternately connected with single bonds in between.
• ⁇ -electron conjugated system contained in aromatic compounds is excluded from the conjugated double bond.
• a numerical range indicated using “to” means a range that includes the numerical values before and after "to” as the minimum and maximum values, respectively.
• the resin (A) in the electron beam curable composition of this embodiment is a resin having a weight average molecular weight of 5,000 to 50,000.
• the type of resin is not particularly limited as long as the weight average molecular weight is 5,000 to 50,000, and any known resin can be used, but a resin that has good compatibility with and is soluble in a (meth)acrylate compound is preferred.
• the weight average molecular weight of the resin is adjusted to 5,000 or more, the required ink viscoelasticity can be easily obtained when the electron beam curable composition is made into ink, and the required emulsification performance can be easily obtained when used in wet lithographic printing.
• the weight average molecular weight is adjusted to 50,000 or less, good adhesion to the film can be easily obtained.
• the weight average molecular weight of the resin (A) is preferably 10,000 to 25,000.
• Resin (A) may have a weight average molecular weight within the above range, and may or may not contain a (meth)acryloyl group in the molecule.
• resin (A) examples include diallyl phthalate resin, rosin-modified resin, polyester resin, epoxy resin, urethane (meth)acrylate resin, polyester (meth)acrylate resin, styrene-acrylic polymerized resin, petroleum resin, allyl resin, etc.
• resin (A) may include at least one selected from the group consisting of diallyl phthalate resin, rosin-modified resin, polyester resin, and urethane (meth)acrylate resin.
• allyl resins other than diallyl phthalate resin such as non-phthalate allyl resin, can also be used as the allyl resin.
• resin (A) may include at least one selected from the group consisting of diallyl phthalate resin, rosin-modified resin, polyester resin, urethane (meth)acrylate resin, and non-phthalate allyl resin.
• the resin (A) contains at least one selected from the group consisting of rosin-modified resins and urethane (meth)acrylate resins.
• the rosin-modified resin refers to a resin that contains a skeleton derived from rosin in the resin skeleton.
• the rosin-modified resin preferably comprises a reaction product of raw material components including rosins, polybasic acids, and polyols.
• the weight average molecular weight of the rosin-modified resin may be preferably 5,000 to 50,000, more preferably 5,400 to 46,000, and even more preferably 15,000 to 30,000.
• the rosins refer to monobasic acids having a cyclic diterpene skeleton, and include rosin acid, disproportionated rosin acid, hydrogenated rosin acid, and alkali metal salts of the above compounds.
• Specific examples of rosins include abietic acid, which has a conjugated double bond, and its conjugated compounds, neoabietic acid, palustric acid, and levopimaric acid.
• Other specific examples include pimaric acid, isopimaric acid, sandaracopimaric acid, and dehydroabietic acid, which do not have a conjugated double bond.
• natural resins containing these rosins include gum rosin, wood rosin, and tall oil rosin.
• Polybasic acids include carboxylic acids with two or more carboxyl groups in one molecule, and their anhydrides.
• polybasic acids examples include 1,2,3,6-tetrahydrophthalic acid, 3-methyl-1,2,3,6-tetrahydrophthalic acid, 4-methyl-1,2,3,6-tetrahydrophthalic acid, 1,2-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, 1,4-cyclohexanedicarboxylic acid, oxalic acid, malonic acid, succinic acid, glutaric acid, pimelic acid, sebacic acid, azelaic acid, alkenylsuccinic acids such as dodecenylsuccinic acid and pentadecenylsuccinic acid, o-phthalic acid, terephthalic acid, trimellitic acid, pyromellitic acid, maleic acid, fumaric acid, citraconic acid, itaconic acid, crotonic acid, isocrotonic acid, and the acid anhydrides thereof.
• Polyols include compounds that have two or more hydroxyl groups in one molecule, such as dihydric alcohols and trihydric or higher alcohols.
• the dihydric alcohol may have a linear, branched, or cyclic structure.
• linear alkylene dihydric alcohols include 1,2-ethanediol, 1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,4-butanediol, 1,2-pentanediol, 1,5-pentanediol, 1,6-hexanediol, 1,2-hexanediol, 1,5-hexanediol, 2,5-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,2-octanediol, 1,9-nonanediol, 1,2-decanediol, 1,10-decanediol, 1,12-dodecanediol, 1,2-dodecanediol, 1,14-t
• branched alkylene dihydric alcohols examples include 2-methyl-2,4-pentanediol, 3-methyl-1,5-pentanediol, 2-methyl-2-propyl-1,3-propanediol, 2,4-dimethyl-2,4-dimethylpentanediol, 2,2-diethyl-1,3-propanediol, 2,2,4-trimethyl-1,3-pentanediol, dimethylol octane, 2-ethyl-1,3-hexanediol, 2,5-dimethyl-2,5-hexanediol, 2-methyl-1,8-octanediol, 2-butyl-2-ethyl-1,3-propanediol, and 2,4-diethyl-1,5-pentanediol.
• cyclic alkylene dihydric alcohols examples include 1,2-cyclohexanediol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, 1,2-cycloheptanediol, tricyclodecane dimethanol, hydrogenated catechol, hydrogenated resorcinol, and hydrogenated hydroquinone.
• trihydric or higher alcohols examples include glycerin, trimethylolpropane, pentaerythritol, 1,2,6-hexanetriol, 3-methylpentane-1,3,5-triol, hydroxymethylhexanediol, trimethylol octane, diglycerin, ditrimethylolpropane, dipentaerythritol, sorbitol, inositol, and tripentaerythritol.
• the urethane (meth)acrylate resin refers to a resin having a urethane bond and a (meth)acryloyl group, which is formed by reacting an isocyanate group with a hydroxyl group.
• the urethane (meth)acrylate resin can be produced according to a method known in the art.
• the urethane (meth)acrylate resin may be a compound obtained by reacting a polyisocyanate, a (meth)acrylate having a hydroxyl group, and a polyol in a compounding ratio that results in an excess of isocyanate groups.
• the urethane (meth)acrylate resin is preferably a compound containing a polyester segment and/or a compound containing a polyether segment.
• a compound is obtained by using a polyether polyol or a polyester polyol as the polyol in the reaction for producing the urethane (meth)acrylate resin.
• the weight average molecular weight of the urethane (meth)acrylate resin may be preferably 5,000 to 50,000, more preferably 5,200 to 46,000, and even more preferably 15,000 to 30,000.
• Polyisocyanates are not particularly limited and include tolylene diisocyanate, 1,5-naphthylene diisocyanate, 4,4'-diphenylmethane diisocyanate, 4,4'-diphenyldimethylmethane diisocyanate, 4,4'-dibenzyl isocyanate, dialkyldiphenylmethane diisocyanate, tetraalkyldiphenylmethane diisocyanate, 1,3-phenylene diisocyanate, 1,4-phenylene diisocyanate, butane-1,4-diisocyanate, hexamethylene diisocyanate, isopropylene diisocyanate, methylene
• diisocyanates include 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, cyclohexane-1,4-diisocyanate, xylylene diisocyanate,
• (Meth)acrylate compounds having a hydroxyl group are not particularly limited and include 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, 2-hydroxy-3-phenoxypropyl (meth)acrylate, polyethylene glycol (meth)acrylate, caprolactone-modified 2-hydroxyethyl (meth)acrylates, glycerin (meth)acrylate, glycerin di(meth)acrylate, etc.
• acrylate diglycerin di(meth)acrylate, diglycerin tri(meth)acrylate, trimethylolpropane (meth)acrylate, trimethylolpropane di(meth)acrylate, ditrimethylolpropane di(meth)acrylate, ditrimethylolpropane tri(meth)acrylate, pentaerythritol di(meth)acrylate, pentaerythritol tri(meth)acrylate, dipentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, etc.
• Polyols include glycols, polyether polyols, and polyester polyols.
• Glycols include compounds with two hydroxyl groups, such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, tripropylene glycol, butanediol, and neopentyl glycol.
• polyether polyols examples include those having two or more hydroxyl groups, such as polymers, copolymers, and graft copolymers of alkylene oxides such as tetrahydrofuran, ethylene oxide, propylene oxide, butylene oxide, oxacyclobutane, and oxacycloheptane; and polyether polyols obtained by condensation of hexanediol, methylhexanediol, heptanediol, octanediol, or mixtures thereof.
• glycols in which alkylene oxides such as ethylene oxide are added to bisphenols such as bisphenol A and bisphenol F can also be used.
• polyester polyols examples include polyester polyols that are the result of a condensation reaction between a polyhydric alcohol component and a polybasic acid component.
• the polyhydric alcohol at least one of a dihydric alcohol and a trihydric or higher alcohol can be used.
• the dihydric alcohol is not particularly limited, and linear, branched, or cyclic alkylene dihydric alcohols can be used.
• linear alkylene dihydric alcohols include 1,3-propanediol, 1,2-butanediol, 1,4-butanediol, 1,2-pentanediol, 1,5-pentanediol, 1,6-hexanediol, 1,2-hexanediol, 1,5-hexanediol, 2,5-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,2-octanediol, 1,9-nonanediol, 1,2-decanediol, 1,10-decanediol, 1,12-dodecaned
• branched alkylene dihydric alcohols examples include 2-methyl-2,4-pentanediol, 3-methyl-1,5-pentanediol, 2-methyl-2-propyl-1,3-propanediol, 2,4-dimethyl-2,4-dimethylpentanediol, 2,2-diethyl-1,3-propanediol, 2,2,4-trimethyl-1,3-pentanediol, dimethylol octane, 2-ethyl-1,3-hexanediol, 2,5-dimethyl-2,5-hexanediol, 2-methyl-1,8-octanediol, 2-butyl-2-ethyl-1,3-propanediol, and 2,4-diethyl-1,5-pentanediol.
• cyclic alkylene dihydric alcohols examples include 1,2-cyclohexanediol, 1,4-cyclohexanediol, 1,4-cyclohexanedimethanol, 1,2-cycloheptanediol, tricyclodecane dimethanol, hydrogenated bisphenol A, hydrogenated bisphenol F, hydrogenated bisphenol S, hydrogenated catechol, hydrogenated resorcinol, and hydrogenated hydroquinone.
• Polyhydric alcohols having a valence of three or more include, but are not limited to, glycerin, trimethylolethane, trimethylolpropane, pentaerythritol, diglycerin, ditrimethylolpropane, sorbitan, sorbitol, dipentaerythritol, inositol, tripentaerythritol, etc.
• the polybasic acid is not particularly limited, and may be either an aliphatic or alicyclic acid.
• the aliphatic polybasic acids include alkenylsuccinic acids such as oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, sebacic acid, azelaic acid, dodecenylsuccinic acid, and pentadecenylsuccinic acid; and examples of the aromatic polybasic acids include isophthalic acid, isophthalic acid, terephthalic acid, himic acid, 3-methylhimic acid, 4-methylhimic acid, trimellitic acid, pyromellitic acid, 1,8-naphthalic acid, and anhydrides thereof.
• alicyclic polybasic acids examples include 1,2,3,6-tetrahydrophthalic acid, 3-methyl-1,2,3,6-tetrahydrophthalic acid, 4-methyl-1,2,3,6-tetrahydrophthalic acid, hexahydrophthalic acid, 3-methylhexahydrophthalic acid, 4-methylhexahydrophthalic acid, and anhydrides thereof.
• compounds having three or more hydroxyl groups such as glycerin, trimethylolpropane, trimethylolethane, pentaerythritol, sorbitol, and methyl glucoside, can also be used as polyhydric alcohols.
• polyols can be used without any particular restrictions. They may be used alone or in combination of two or more types according to their respective characteristics. For example, from the viewpoint of the transparency and moist heat resistance of the coating film, it is preferable to use polyether polyols, and it is particularly preferable to mainly use polyols having a polypropylene glycol skeleton. Furthermore, from the viewpoint of adhesive strength and heat resistance, it is preferable to use polyester polyols.
• the (meth)acrylate compound (B) is a (meth)acrylate compound having a weight average molecular weight of 700 to 3,000 and a weight average molecular weight per (meth)acryloyl group of 100 to 300.
• the weight average molecular weight of the (meth)acrylate compound (B) may be preferably 750 to 2,500, more preferably 800 to 2,000, even more preferably 900 to 1,800, and particularly preferably 1,000 to 1,700.
• the weight average molecular weight and the weight average molecular weight per (meth)acryloyl group are within the above ranges, an excellent balance of low migration properties, film strength, and adhesion is achieved.
• the (meth)acrylate compound (B) may suitably be one having a weight average molecular weight of 700 to 3,000 and a weight average molecular weight per (meth)acryloyl group of 100 to 300. More preferably, one or more compounds selected from the group consisting of amine-modified (meth)acrylate, polyester (meth)acrylate, polyether (meth)acrylate, urethane (meth)acrylate, silicone (meth)acrylate, epoxy (meth)acrylate, and epoxidized vegetable oil (meth)acrylate may be used. In one embodiment, the (meth)acrylate compound (B) preferably includes an amine-modified (meth)acrylate and/or a polyester (meth)acrylate.
• the amine-modified (meth)acrylate is a (meth)acrylate compound having one or more amino groups in the molecule.
• the amine-modified (meth)acrylate preferably has an amine equivalent of 400 to 2,500.
• the surface curability, film strength, and background scumming during water-based lithographic printing are all excellent.
• the amine equivalent can be calculated as the molecular weight per active hydrogen derived from the amine in the amine-modified (meth)acrylate.
• the amine-modified (meth)acrylate is preferably contained in an amount of 0.5 to 10% by mass based on the total mass of the electron beam curable composition.
• the content is within this range, the surface curability, film strength, and background scumming during wet lithographic printing are all good.
• examples of amine-modified (meth)acrylates include EBECRYL LEO 10553 (weight average molecular weight 780, 4 acryloyl groups per molecule, weight average molecular weight per acryloyl group 195) and EBECRYL 80 (weight average molecular weight 1000, 4 acryloyl groups per molecule, weight average molecular weight per acryloyl group 250) manufactured by DAICEL-ALLNEX.
• polyester (meth)acrylate is a (meth)acrylate compound having a polyester structure in the molecule (except when it has an amino group).
• polyester (meth)acrylate it is desirable for the polyester (meth)acrylate to have 3 to 10 acryloyl groups in the molecule.
• the polyester (meth)acrylate is contained in an amount of 10 to 50% by mass based on the total mass of the electron beam curable composition.
• a content of 10 to 50% by mass results in good adhesion, viscoelasticity, and emulsification during water-based lithographic printing.
• polyester (meth)acrylates examples include DAICEL-ALNEX's EBECRYL LEO10801 (weight average molecular weight 1,500, number of acryloyl groups per molecule 6), EBECRYL450 (weight average molecular weight 1,600, number of acryloyl groups per molecule 6), and EBECRYL800 (weight average molecular weight 780, number of acryloyl groups per molecule 6).
• EBECRYL810 weight average molecular weight 1,000, 4 acryloyl groups per molecule
• EBECRYL812 weight average molecular weight 800, 3 acryloyl groups per molecule
• EBECRYL846 weight average molecular weight 1,100, 6 acryloyl groups per molecule
• EBECRYL870 weight average molecular weight 1,500, 6 acryloyl groups per molecule
• the (meth)acrylate compound (B) in combination with the above-mentioned amine-modified (meth)acrylate and the above-mentioned polyester acrylate.
• the (meth)acrylate compound (B) may be polyether (meth)acrylate, urethane (meth)acrylate, silicone (meth)acrylate, epoxy (meth)acrylate, or epoxidized vegetable oil (meth)acrylate.
• Known materials may be used as long as the weight average molecular weight is 700 to 3,000 and the weight average molecular weight per (meth)acryloyl group is 100 to 300. Modified products of these polyether (meth)acrylate, urethane (meth)acrylate, silicone (meth)acrylate, epoxy (meth)acrylate, or epoxidized vegetable oil (meth)acrylate may be used after various modifications.
• the ratio (B/A) of the content (A mass%) of the resin (A) to the content (B mass%) of the (meth)acrylate compound (B) in the total mass of the composition is preferably 0.5 to 8.0, and more preferably 2.0 to 4.0.
• the ratio (B/A) of the content (mass%) of the resin (A) to the (meth)acrylate compound (B) in the total mass of the composition is 0.5 to 8.0, it is possible to achieve both the necessary adhesion and the viscoelasticity of the ink when made into a water-based lithographic printing ink.
• the pigment (C) may be a colored pigment or an extender pigment.
• Colored pigments are broadly classified into white and pigments having other colors.
• Colored pigments may be either inorganic pigments or organic pigments. By using organic pigments, it is possible to prepare white inks and colored inks having other colors.
• inorganic pigments among the colored pigments include yellow lead, zinc yellow, iron blue, cadmium red, titanium oxide, zinc oxide, red oxide, ultramarine, carbon black, graphite, and aluminum powder.
• organic pigments among the colored pigments include soluble azo pigments such as ⁇ -naphthol, ⁇ -oxynaphthoic acid, ⁇ -oxynaphthoic acid arylide, acetoacetic acid arylide, and pyrazolone; insoluble azo pigments such as ⁇ -naphthol, ⁇ -oxynaphthoic acid arylide, acetoacetic acid arylide monoazo, acetoacetic acid arylide disazo, and pyrazolone; copper phthalocyanine blue; halogenated (chlorinated or brominated) azo pigments; Examples of pigments include phthalocyanine pigments such as sulfonated copper phthalocyanine blue, metal-free phthalocyanine, and polycyclic and heterocyclic pigments such as quinacridone, dioxazine, threne (pyranthrone, anthanthrone,
• the color pigment may be used alone or in combination with two or more of these, or may be used in combination with one or more extender pigments, which will be described later.
• the content of the colored pigment is preferably 2 to 30 mass %, more preferably 5 to 25 mass %, of the total mass of the electron beam curable composition in the case of a color ink. Also, it is preferable that the content of titanium oxide is 30 to 70 mass %, more preferably 40 to 60 mass %, of the total mass of the electron beam curable composition in the case of a white ink. Also, as described below, when a transparent ink (also called a varnish) and a dilution medium are prepared using an extender pigment, the electron beam curable composition does not need to contain a colored pigment.
• the extender pigment means a pigment that does not have coloring power, and is distinguished from the colored pigments described above.
• specific examples of the extender pigment include barium sulfate, alumina white, calcium carbonate, magnesium carbonate, aluminum silicate, magnesium silicate, silicon dioxide, and aluminum hydroxide. These may be used alone or in combination of two or more.
• the content of the extender pigment is preferably adjusted according to the purpose. For example, for the purpose of improving the fluidity and misting resistance of the ink, it is preferable to use 5 mass % or less of the extender pigment based on the total mass of the electron beam curable composition. In one embodiment, the extender pigment does not need to be used when preparing the ink. On the other hand, when the electron beam curable composition is used as a transparent ink (varnish), the content of the extender pigment is preferably adjusted depending on the application.
• the extender pigment is preferably used in an amount of 30 mass% or less based on the total mass of the electron beam curable composition (varnish).
• the content of the extender pigment may be preferably 0.1 to 30 mass%, more preferably 0.5 to 20 mass%, and even more preferably 1 to 10 mass%.
• the total content of the resin (A), the (meth)acrylate compound (B), and the pigment (C) may be 60 to 90% by mass relative to the total mass of the electron beam curable composition.
• the necessary printability, such as viscoelasticity, fluidity, and transferability, required for water-based lithographic printing can be easily obtained.
• the total content of (A), (B) and (C) is preferably 60 to 80% by mass, and more preferably 65 to 75% by mass.
• the total content of (A), (B) and (C) is preferably 70 to 90% by mass, and more preferably 75 to 85% by mass.
• the total content of (A), (B) and (C) is preferably 60 to 80% by mass, and more preferably 65 to 75% by mass.
• the content of the above other (meth)acrylate compound may be 10 to 40 mass% with respect to the total mass of the electron beam curable composition.
• a compound having a weight average molecular weight of 500 or more is preferable to use as the other (meth)acrylate compound.
• the content is preferably 25 mass% or less, as described below.
• the other (meth)acrylate compounds can be appropriately selected depending on the required properties of the cured film, and may be used alone or in combination of two or more kinds.
• the other (meth)acrylate compound preferably has a weight average molecular weight of 500 or more and is composed of a tri- or higher functional (meth)acrylate compound, from the viewpoints of curability and low migration.
• the electron beam curable composition can be produced by mixing the resin (A), the (meth)acrylate compound (B), and the pigment (C). In another embodiment, the electron beam curable composition can be produced by using an electron beam curable varnish containing the resin (A) described later.
• the electron beam curable varnish can be prepared using resin (A) and a (meth)acrylate compound.
• the electron beam curable varnish preferably contains 10 to 80 mass% of resin (A) and 20 to 90 mass% of the (meth)acrylate compound based on the total mass of the varnish. More preferably, it may contain 20 to 70 mass% of resin (A) and 30 to 80 mass% of the (meth)acrylate compound.
• the (meth)acrylate compound may be any compound capable of adjusting the viscosity of the varnish to a desired range, and both the (meth)acrylate compound (B) and other (meth)acrylate compounds (i.e., different from the (meth)acrylate compound (B)) can be used.
• the electron beam curable varnish may be prepared using the resin (A) and a (meth)acrylate compound (different from the (meth)acrylate compound (B)).
• the electron beam curable composition can be produced by further adding and mixing the (meth)acrylate compound (B) and the pigment (C) to the above-mentioned varnish.
• the amount of the varnish to be blended is preferably adjusted so that the ratio (B/A) of the contents of the resin (A) and the (meth)acrylate compound (B) in the electron beam curable composition is within a predetermined range, taking into account the content of the resin (A) in the varnish.
• the (meth)acrylate compounds other than the resin (A) and the (meth)acrylate compound (B) used in preparing the electron beam curable varnish and the electron beam curable composition preferably have a weight average molecular weight of 500 or more in order to ensure low migration.
• the weight average molecular weight of the (meth)acrylate compounds may more preferably be 550 or more, even more preferably 650 or more, and even more preferably 750 or more. However, this embodiment does not exclude the use of (meth)acrylate compounds having a weight average molecular weight of less than 500.
• the electron beam curable varnish and the electron beam curable composition may contain a (meth)acrylate compound having a weight average molecular weight of less than 500.
• the content of the (meth)acrylate compound having a weight average molecular weight of less than 500 may be preferably 25 mass% or less, more preferably 20 mass% or less, and even more preferably 15 mass% or less, based on the total mass of the composition.
• the above content may be 0 mass%.
• (meth)acrylate compound having a weight average molecular weight of less than 500 examples include 2-ethylhexyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, ⁇ -carboxyethyl (meth)acrylate, 4-tert-butylcyclohexanol (meth)acrylate, tetrahydrofurfuryl acrylate, alkoxylated tetrahydrofurfuryl acrylate, caprolactone (meth)acrylate, lauryl (meth)acrylate, stearyl (meth)acrylate, isoamyl (meth)acrylate, 2-phenoxyethyl (meth)acrylate, isodecyl (meth)acrylate, and 3,3,5-trimethylcyclohexanol (meth).
• monofunctional (meth)acrylate compounds include 2-ethylhexyl (meth)acrylate, 2-hydroxye
• acrylate cyclohexyl (meth)acrylate, isobornyl (meth)acrylate, norbornyl (meth)acrylate, dicyclopentanyl (meth)acrylate, dicyclopentenyl (oxyethyl) (meth)acrylate, 1,4-cyclohexanedimethanol (meth)acrylate, cyclic trimethylolpropane formal (meth)acrylate, benzyl (meth)acrylate, (2-methyl-2-ethyl-1,3-dioxolan-4-yl)methyl acrylate, acryloyl morpholine, N-vinyl carbazole, 1-vinylimidazole, N-vinyl-2-pyrrolidone, N-vinyl caprolactam, N-vinyl formamide, and the like.
• Bifunctional (meth)acrylate compounds include hexanediol diacrylate, tripropylene glycol diacrylate, 1,3-butylene glycol di(meth)acrylate, 1,4-butanediol di(meth)acrylate, 3-methyl-1,5-pentanediol di(meth)acrylate, 1,6-hexanediol di(meth)acrylate, 1,9-nonanediol di(meth)acrylate, 1,10-decanediol di(meth)acrylate, 1,2-dodecanediol di(meth)acrylate, neopentyl glycol di(meth)acrylate, polyethylene glycol (200) di(meth)acrylate, polyethylene glycol (300) di(meth)acrylate, and hydride.
• acrylates include roxypivalic acid neopentyl glycol di(meth)acrylate, dipropylene glycol di(meth)acrylate, tripropylene glycol di(meth)acrylate, EO-modified 1,6-hexanediol di(meth)acrylate, PO-modified neopentyl glycol di(meth)acrylate, (neopentyl glycol-modified) trimethylolpropane di(meth)acrylate, dimethyloltricyclodecane di(meth)acrylate, cyclohexanedimethanol di(meth)acrylate, dimethylol-tricyclodecane di(meth)acrylate, dicyclopentanyl di(meth)acrylate, and tris(2-hydroxyethyl)isocyanurate di(meth)acrylate.
• trifunctional or higher (meth)acrylate compounds include trimethylolpropane triacrylate, trimethylolpropane EO-modified (3 mol) triacrylate, trimethylolpropane PO-modified (3 mol) triacrylate, pentaerythritol triacrylate, glycerin PO-modified (3 mol) triacrylate, ditrimethylolpropane tetraacrylate, pentaerythritol tetraacrylate, etc.
• the (meth)acrylate compound having a weight average molecular weight of less than 500 one of the exemplified compounds may be used alone, or two or more may be used in combination. In one embodiment, it is preferable to use a polyfunctional (meth)acrylate.
• the polyfunctional (meth)acrylate it is preferable to use at least one of a bifunctional (meth)acrylate compound and a trifunctional or higher (meth)acrylate compound, and it is more preferable to use a trifunctional or higher (meth)acrylate compound.
• the electron beam curable varnish of the above embodiment may contain a polymerization inhibitor, described below, in addition to the above components.
• the polymerization inhibitor can be added and used in a conventional manner.
• the amount of the polymerization inhibitor is preferably 3 mass % or less, based on the total mass of the electron beam curable varnish, and more preferably in the range of 0.01 to 1 mass %.
• the electron beam curable varnish can be produced by mixing the above components under temperature conditions between room temperature and 160°C.
• resin (A) containing at least one selected from the group consisting of diallyl phthalate resin, rosin modified resin, polyester resin, urethane (meth)acrylate resin, and non-phthalate type allyl resin not containing a phthalate structure, a polyfunctional (meth)acrylate compound such as dipentaerythritol hexaacrylate, and a polymerization inhibitor containing hydroquinone.
• resin (A) containing at least one selected from the group consisting of diallyl phthalate resin, rosin modified resin, polyester resin, urethane (meth)acrylate resin, and non-phthalate type allyl resin not containing a phthalate structure, a polyfunctional (meth)acrylate compound such as dipentaerythritol hexaacrylate, and a polymerization inhibitor containing hydroquinone.
• the electron beam curable composition may further contain a polymerization inhibitor in addition to the above components.
• the polymerization inhibitor can be added and used by a conventional method.
• the amount of the polymerization inhibitor is preferably 3 mass % or less, and more preferably 0.01 to 1 mass %, based on the total mass of the electron beam curable composition, from the viewpoint of not inhibiting the curability.
• polymerization inhibitors include (alkyl)phenols, hydroquinone, catechol, resorcinol, p-methoxyphenol, t-butylcatechol, t-butylhydroquinone, pyrogallol, 1,1-picrylhydrazyl, phenothiazine, p-benzoquinone, nitrosobenzene, 2,5-di-tert-butyl-p-benzoquinone, dithiobenzoyl disulfide, picric acid, cupferron, aluminum N-nitrosophenylhydroxylamine, tri-p-nitrophenylmethyl, N-(3-oxyanilino-1,3-dimethylbutylidene)aniline oxide, dibutyl cresol, cyclohexanone oxime cresol, guaiacol, o-isopropylphenol, butyraldoxime, methyl ethyl ketoxime, cyclohexan
• compounds having two hydrocarbon groups each at the 2-position and the 6-position on the piperidine ring are preferred. More specifically, it is preferred to use one or more compounds selected from hindered amines such as 2,2,6,6-tetraalkylpiperidine derivatives, 2,2,6,6-tetramethylpiperidine derivatives, 1-alkyl-2,2,6,6-tetramethylpiperidine derivatives, and 1-hydro-2,2,6,6-tetramethylpiperidine derivatives.
• hindered amines such as 2,2,6,6-tetraalkylpiperidine derivatives, 2,2,6,6-tetramethylpiperidine derivatives, 1-alkyl-2,2,6,6-tetramethylpiperidine derivatives, and 1-hydro-2,2,6,6-tetramethylpiperidine derivatives.
• the curing reaction in the printing machine can be inhibited, and excellent storage stability can be easily provided.
• the above compounds are also available as commercially available products. For example, there is a product name "Polystop 7
• the electron beam curable composition may further contain various additives such as a viscoelasticity modifier, a dispersant, an anti-friction agent, an anti-blocking agent, and a slip agent depending on the purpose.
• various additives can be added to the composition by a conventional method. When various additives are added to the composition, it is preferable to adjust the blending amount within a range that does not inhibit the effects of other components.
• the blending amount of various additives is preferably 5 mass% or less based on the total mass of the electron beam curable composition.
• substantially free means that the target component is not intentionally added, and the content due to unintentional addition is less than 1% by mass. Unintentional addition includes trace amounts contained in each raw material, contamination during the composition manufacturing process, and the printing process.
• the electron beam curable composition is substantially free of organic solvents.
• organic solvents used as viscosity modifiers in printing inks may contain MOSH/MOAH, which are persistent organic pollutants.
• non-VOC volatile components
• it is preferable that the electron beam curable composition is substantially free of organic solvents.
• the electron beam curable composition is substantially free of a photopolymerization initiator.
• a photopolymerization initiator is expected to have the effect of expressing and improving the curability of an active energy beam curable composition.
• the packaging market particularly in food packaging materials, toiletry packaging materials, medical packaging materials, and the like, there is a concern that the components of the photopolymerization initiator may migrate, resulting in a decrease in safety and quality.
• it is preferable that the electron beam curable composition is substantially free of a photopolymerization initiator.
• raw materials derived from biomass using renewable resources such as plants as the various raw materials used in the electron beam curable composition.
• the ink when the electron beam curable composition is used as a lithographic printing ink, the ink can be produced by flushing, kneading, and mixing the above-mentioned components under temperature conditions between room temperature and 120°C.
• various equipment such as a kneader, a triple roll, an attritor, a sand mill, and a gate mixer.
• the resin (A) may be added in the form of the resin (A) itself, or in the form of an electron beam curable varnish containing the above-mentioned resin (A).
• a laminate according to one embodiment of the present invention has a substrate and a printed layer formed on at least one main surface of the substrate and composed of a cured product of the electron beam curable composition according to the above embodiment.
• the laminate when the electron beam curable composition is an electron beam curable ink, the laminate is obtained by printing the electron beam curable ink on the substrate to form a coating film, and curing this coating film with an electron beam.
• the electron beam curable composition is an electron beam curable varnish
• the laminate is obtained by printing the electron beam curable varnish on the substrate, or printing the electron beam curable varnish on a printed material on which ink has been printed on the substrate to form a coating film, and curing this coating film with an electron beam.
• the substrate that can be used is preferably a film-like substrate, for example, a polyolefin substrate such as polyethylene or polypropylene, a polyester substrate such as polyethylene terephthalate or polylactic acid, a polycarbonate substrate, a polystyrene-based substrate such as polystyrene, AS resin or ABS resin, a nylon substrate, a polyamide substrate, a polyvinyl chloride substrate, a polyvinylidene chloride substrate, a cellophane substrate, a paper substrate, an aluminum substrate, or a film-like substrate made of a composite material thereof.
• a polyolefin substrate such as polyethylene or polypropylene
• a polyester substrate such as polyethylene terephthalate or polylactic acid
• a polycarbonate substrate such as polyethylene terephthalate or polylactic acid
• a polycarbonate substrate such as polyethylene terephthalate or polylactic acid
• a polycarbonate substrate such as polyethylene terephthalate or polylactic acid
• a deposition substrate in which an inorganic compound such as silica, alumina, or aluminum is deposited on a polyethylene terephthalate substrate or a nylon substrate can also be used, and the deposition surface may be further coated with polyvinyl alcohol or the like.
• the substrate is preferably subjected to an easy-adhesion treatment on the surface to be printed (the surface in contact with the printing layer).
• Examples of the easy-adhesion treatment include corona discharge treatment, ultraviolet/ozone treatment, plasma treatment, oxygen plasma treatment, primer treatment, etc.
• an acrylic coating treatment, a polyester treatment, a polyvinylidene chloride treatment, etc. may be performed.
• a paper substrate may be used as the substrate.
• the paper substrate may be ordinary paper or cardboard.
• the thickness of the paper substrate is not particularly specified, but for example, a substrate having a thickness of 0.2 mm to 1.0 mm and a thickness of 20 to 150 g/ m2 may be used, and the printed surface may be easily adhesively treated.
• the paper substrate may have a surface that is vapor-deposited with a metal such as aluminum for the purpose of imparting design.
• the surface may be coated with an acrylic resin, a urethane resin, a polyester resin, a polyolefin resin, or other resin, and may further be subjected to a surface treatment such as a corona treatment.
• coated paper and art paper may be used.
• the printing method for the electron beam curable composition is not particularly limited, and known methods can be used.
• the electron beam curable composition is an ink
• specific examples include wet offset printing (normal lithographic printing using dampening water), waterless offset printing (lithographic printing without dampening water), resin letterpress printing, and screen printing. Of these, it is preferable to use offset printing, and it is more preferable to use wet offset printing.
• suitable applications include wet offset printing, waterless offset printing, resin letterpress printing, and screen printing.
• viscoelasticity it is possible to select various printing methods such as flexographic printing, gravure printing, and inkjet printing, as well as coating with various coaters.
• the electron beam curable composition is printed by various printing methods (after a coating of the composition is formed), and then the coating is cured through an electron beam irradiator to form a printed layer. It is preferable to use electron beams for curing, taking into consideration the balance between damage to the substrate such as a film and the curability of the electron beam curable composition. In one embodiment, it is preferable to irradiate electron beams adjusted under conditions of an acceleration voltage of 40 to 120 kV, preferably 60 to 110 kV, and an exposure dose of 10 to 60 kGy, more preferably 15 to 45 kGy. When the exposure dose is 10 to 60 kGy, sufficient film strength is obtained, and problems due to damage to the film, such as a decrease in film strength, odor, and yellowing, can be suppressed.
• the electron beam curable composition of the above embodiment can be suitably used to form a printed layer on various substrates. It can also be used to form printed materials such as printed materials for forms, printed materials for various books, printed materials for various packaging such as carton paper, printed materials for various plastics, printed materials for stickers/labels, fine art prints, and metal prints (fine art prints, printed materials for beverage cans, printed materials for canned food such as canned food).
• the electron beam curable composition can be suitably used as an ink or varnish for forming packaging materials for food packages (hereinafter also referred to as food packaging materials).
• One embodiment of the present invention relates to a method for manufacturing a laminate having a substrate and a layer formed on the substrate and composed of a cured product of an electron beam curable composition.
• This manufacturing method includes printing the electron beam curable composition of the above embodiment onto the substrate to form a coating film, and irradiating the coating film with an electron beam to cure the coating.
• the coating film is preferably cured by irradiating it with an electron beam under conditions of an acceleration voltage of 40 to 120 kV and an exposure dose of 10 to 60 kGy.
• the electron beam curable composition also includes a resin (A) having a weight average molecular weight of 5,000 to 50,000, a (meth)acrylate compound (B) having a weight average molecular weight of 700 to 3,000 and a weight average molecular weight per (meth)acryloyl group of 100 to 300, and a pigment (C), and it is preferable that the resin (A) includes one or more selected from the group consisting of rosin-modified resins, urethane (meth)acrylate resins, polyester resins, and diallyl phthalate resins, and that the (meth)acrylate compound (B) includes one or more selected from the group consisting of amine-modified (meth)acrylates and polyester (meth)acrylates.
• the resin (A) includes one or more selected from the group consisting of rosin-modified resins, urethane (meth)acrylate resins, polyester resins, and diallyl phthalate resins
• the laminate may have a structure for use as a food packaging material.
• it may be a surface-printed laminate having a printed layer formed from an ink or varnish of an electron beam curable composition on one side of a base film, and a metal foil, various films, a sealant layer, etc., on the other side of the film via an adhesive layer.
• the food packaging material may be processed into various package shapes, such as a lid shape for a container, or a bag-like shape such as a pouch.
• the outermost layer of the food packaging material (package) is the printed layer. Therefore, by improving the film strength of the printed layer formed from the ink or varnish of the electron beam curable composition of the above embodiment, defects such as rubbing and damage of the package due to vibration and friction during transportation can be easily improved. In this way, the benefits of improving the film strength are significant in a surface-printed laminate.
• the laminate is not limited to a surface-printed form, and may be a reverse-printed form. In a reverse-printed laminate, since it has a structure in which a film or the like is further laminated on the printed layer on the substrate, defects such as rubbing and damage are unlikely to occur.
• properties required for food packaging materials such as excellent adhesion to the substrate and low migration, can be easily obtained.
• the laminate preferably has a concentration of the (meth)acrylate compound that migrates the most in a migration resistance test described later, which is less than 50 ppb.
• a plastic film such as an OPP film is used as the substrate, and an electron beam curable composition (ink or varnish) is printed on one side of the film in an amount of 2 to 3 g/ m2 to form a coating film.
• An electron beam irradiator is used to irradiate the coating film with electron beams to harden the coating film and form a printed surface.
• the irradiation conditions may be, for example, an acceleration voltage of 110 kV and an electron beam dose of 30 kGy.
• the substrate is then stacked and held so that the printed surface of the substrate and the non-printed surface of the other substrate are in contact with each other. More specifically, the substrate can be held for 10 days at 25°C and 50% humidity with a load of 1 kg/ dm2 .
• the residual monomer (unreacted (meth)acrylate component) is extracted with ethanol. More specifically, for example, the residual monomer is extracted with 50 ml of 95% ethanol for an area of 0.5 dm2 of the non-printed surface at 60° C. for 10 days.
• the extract is analyzed using a quadrupole time-of-flight mass spectrometer and a liquid chromatograph to determine the concentration of each of the (meth)acrylate compounds present in the ethanol.
• the laminate of the above embodiment can easily meet safety requirements such as low migration, making it suitable for use as a food packaging material.
• the rosin acids used as raw materials were analyzed by gas chromatography mass spectrometry to determine the ratio (%) of each peak area relative to the total rosin acid peak area of 100%. More specifically, the content ratio of conjugated rosin acids contained in the rosin acids that undergo a Diels-Alder addition reaction with an ⁇ , ⁇ -unsaturated carboxylic acid or anhydride thereof (B) to other than the conjugated rosin acids was determined from the ratio of the corresponding peak areas.
• the reaction solution of the Diels-Alder addition reaction was analyzed by a gas chromatography mass spectrometer, and the progress of the reaction was confirmed by the decrease in the detection peaks of the rosin acids (a1) and ⁇ , ⁇ -unsaturated carboxylic acid or its acid anhydride (a2) used as raw materials.
• the reaction was terminated when no change was observed in the decrease in the detection peaks.
• the weight average molecular weight (Mw) was measured using a gel permeation chromatography (HLC-8320) manufactured by Tosoh Corporation. A calibration curve was prepared using a standard polystyrene sample. Tetrahydrofuran was used as the eluent, and three TSKgel Super HM-M columns (manufactured by Tosoh Corporation) were used. The measurement was performed under the conditions of a flow rate of 0.6 mL/min, an injection volume of 10 ⁇ L, and a column temperature of 40° C.
• rosin-modified resin A rosin-modified resin was prepared according to the following recipe.
• the gum rosin used in the recipe had a conjugated rosin acid content of 80% by mass that undergoes a Diels-Alder addition reaction with an ⁇ , ⁇ -unsaturated carboxylic acid or an acid anhydride thereof (a2), and a content of substances other than the conjugated rosin acid of 20% by mass.
• urethane (meth)acrylate resin a urethane (meth)acrylate resin was prepared.
• polyester polyol 1 (Preparation of polyester polyol 1) Into a four-neck flask equipped with a stirrer, a Dean-Stark tube, a thermometer, and a gas inlet tube, 36.2 parts of ethylene glycol and 63.8 parts of adipic acid were placed as raw materials, and the mixture was heated with stirring to 220° C. The reaction was carried out while removing the condensed water generated as the reaction proceeded from the system, and the reaction was terminated when the theoretical amount of dehydration was reached, thereby obtaining polyester polyol 1.
• Polyester polyol resins 2 to 6 were prepared in the same manner as in the preparation of polyester polyol 1, except that the formulation of polyester polyol 1 was changed to the formulations shown in Table 2.
• urethane (meth)acrylate resin 1 (Preparation of urethane (meth)acrylate resin 1) Into a four-neck flask equipped with a stirrer, a cooler, a thermometer, and a gas inlet tube, 50.4 parts of polyester polyol 1 and 29.3 parts of hexamethylene diisocyanate were placed and reacted with stirring for 3 hours at 100° C. Then, 20.3 parts of HEA were placed and further reacted for 5 hours at 110° C. to obtain urethane (meth)acrylate resin 1.
• polyester resin was prepared according to the following recipe. Into a four-neck flask equipped with a stirrer, a Dean-Stark tube, a thermometer, and a gas inlet tube, 10 parts of glycerin, 20 parts of ethylene glycol, and 59 parts of phthalic anhydride were placed as raw materials, and heated with stirring to 220° C. The reaction was carried out while removing the condensed water generated as the reaction proceeded from the system, and when the theoretical amount of dehydration was reached, the reaction was stopped to obtain polyester resin 1 (weight average molecular weight: 10,500, hydroxyl value 119 KOH/g).
• DAP-K diallyl phthalate resin, weight average molecular weight 25,000, manufactured by Osaka Soda Co., Ltd.
• RADPAR AD-032 non-phthalate allyl resin, weight average molecular weight 32,000, manufactured by Osaka Soda Co., Ltd.
• Varnish raw materials were placed in a four-neck flask equipped with a stirrer, a Dean-Stark tube, a thermometer, and a gas inlet tube according to the formulation in Table 4, heated to 100°C with stirring, and stirred and melted at 100°C for 2 hours to obtain Varnishes 1 to 15 shown in Table 4.
• Details of the commercially available products used are as follows: Miramer M600: dipentaerythritol hexaacrylate (weight average molecular weight: 578, number of acryloyl groups per molecule: 6, weight average molecular weight per acryloyl group: 96, manufactured by Bigen Specialty Chemical Co., Ltd.)
• ⁇ FG-7330G LIONOL BLUE FG-7330G (indigo pigment, manufactured by Toyo Color Co., Ltd.)
• CR-90-2 Tipaque CR-90-2 (titanium oxide, manufactured by Ishihara Sangyo Kaisha, Ltd.)
• ⁇ AEROSIL200V fumed silica, manufactured by Nippon Aerosil Co., Ltd.
• Hi-Filler #5000PJ talc, manufactured by Matsumura Sangyo Co., Ltd.
• EBECRYL 10551 (amine-modified acrylate, weight average molecular weight: 500, number of acryloyl groups per molecule: 2.5, weight average molecular weight per acryloyl group: 200, manufactured by Daicel Allnex Corporation)
• EBECRYL 10553 (amine-modified acrylate, weight average molecular weight: 780, number of acryloyl groups per molecule: 4, weight average molecular weight per acryloyl group: 195, manufactured by Daicel Allnex Corporation)
• EBECRYL 80 (amine-modified acrylate, weight average molecular weight: 1,000, number of acryloyl groups per molecule: 4, weight average molecular weight per acryloyl group: 250, manufactured by Daicel Allnex Corporation)
• Laromer PO 9139 (amine-modified acrylate, weight average molecular weight: 5,900, manufactured by BASF)
• EBECRYL 851 (polyester acrylate, weight average molecular weight: 500, number of acryloyl groups per molecule: 2.5, weight average molecular weight per acryloyl group: 200, manufactured by Daicel Allnex Corporation)
• EBECRYL 800 (polyester acrylate, weight average molecular weight: 780, number of acryloyl groups per molecule: 4, weight average molecular weight per acryloyl group: 195, manufactured by Daicel Allnex Corporation)
• EBECRYL 810 (polyester acrylate, weight average molecular weight: 1,000, number of acryloyl groups per molecule: 4, weight average molecular weight per acryloyl group: 250, manufactured by Daicel Allnex Corporation)
• EBECRYL 450 (polyester acrylate, weight average molecular weight: 1,600, number of acryloyl groups per molecule: 6, weight average molecular weight per acryloyl group: 267, manufactured by
• Miramer M3150 (trimethylolpropane ethylene oxide adduct (15 moles) triacrylate, weight average molecular weight 956, number of acryloyl groups per molecule: 3, weight average molecular weight per acryloyl group: 319, manufactured by MIWON Corporation)
• Miramer M3160 (trimethylolpropane ethylene oxide adduct (6 moles) triacrylate, weight average molecular weight 560, number of acryloyl groups per molecule: 3, weight average molecular weight per acryloyl group: 187, manufactured by MIWON Corporation)
• Miramer M3130 (trimethylolpropane EO modified (3 moles) triacrylate, weight average molecular weight 428, number of acryloyl groups per molecule: 3, weight average molecular weight per acryloyl group: 143, manufactured by MIWON Corporation)
• the solvent was evaporated from the coating film in a drying oven, it was laminated with aluminum foil (thickness 7 ⁇ m, hereinafter referred to as AL) to obtain a PET/AL laminate.
• AL aluminum foil
• the laminate adhesive was applied to the AL foil surface of the obtained laminate in the same manner as above, the solvent was evaporated, and the applied surface was bonded to an OPA film (EMBLEM ONM, 15 ⁇ m).
• OPA film EBLEM ONM, 15 ⁇ m
• the laminate adhesive was applied to the OPA film surface of the obtained laminate in the same manner as above, the solvent was evaporated, and the applied surface was bonded to the corona-treated surface of an unstretched polypropylene film (FHK2, thickness 40 ⁇ m, manufactured by Futamura Chemical Co., Ltd., hereinafter referred to as "CPP").
• the obtained laminate was left for 24 hours in an environment of 35° C. and 60% RT to 80% RT humidity to obtain a laminate having a structure of PET/adhesive layer/AL/adhesive layer/OPA/adhesive layer/CPP.
• the inks and varnishes of Examples 1 to 27 and Comparative Examples 1 to 12 were printed on the film in an amount of 1 g/ m2 using an RI tester (a simple color development device manufactured by Akebono Seisakusho Co., Ltd.) to form a coating film.
• the coating film after printing was immediately cured using an electron beam irradiator EC250/15/180L manufactured by Iwasaki Electric Co., Ltd. at an acceleration voltage of 110 kV and an electron beam dose of 30 kGy to obtain a laminate having a configuration of ink layer (cured coating film)/PET/adhesive layer/AL/adhesive layer/OPA/adhesive layer/CPP.
• the obtained laminate was used to make pouches measuring 14 cm x 18 cm, which were filled with 150 ml of water. 20 of these pouches were made and placed in cardboard boxes. Transport vibration tests were carried out for 15 minutes in the horizontal direction, 15 minutes in the vertical direction, and 15 minutes in the height direction under conditions of a controlled acceleration of 1 G and a vibration frequency of 6 Hz, and the results were evaluated according to the following criteria.
• An industrially practical level is "3" or higher, with "4" or higher being more preferable.
• an adhesive tape (cellophane tape (width 12 mm) manufactured by Nichiban Co., Ltd.) was applied to the printed surface (surface of the printed layer) and quickly peeled off at an angle of 180 degrees, and the area percentage of the coating film remaining on the printed matter (laminate) side was evaluated on a 5-point scale according to the following criteria.
• An industrially practical level is "3" or higher, with "4" or higher being more preferable.
• the area of the remaining coating film is 90% or more.
• the area of the remaining coating film is 70% or more and less than 90%.
• the area of the remaining coating film is 50% or more and less than 70%.
• the area of the remaining coating film is 25% or more and less than 50%. 1: The area of the remaining coating film is less than 25%.
• OPP FOR (30 ⁇ m) manufactured by Futamura Chemical Co., Ltd.
• PE White polyethylene film (50 ⁇ m)
• PET Emblet PTM (12 ⁇ m) manufactured by Unitika Ltd.
• OPA Emblem ONM (15 ⁇ m) manufactured by Unitika Ltd.
• the coated surface was attached to the corona-treated surface of an unstretched polypropylene film (FHK2, manufactured by Futamura Chemical Co., Ltd., thickness 40 ⁇ m, hereinafter referred to as "CPP").
• CPP unstretched polypropylene film
• the film was left for 24 hours in an environment of 35°C and humidity 60% RT to 80% RT to obtain a laminate having an OPP/adhesive layer/CPP configuration.
• the inks of Examples 1 to 29 and Comparative Examples 1 to 12 were printed using an RI tester (a simple color development device manufactured by Akebono Seisakusho Co., Ltd.) so as to give a coating amount of 2 to 3 g/m 2.
• the coating film after printing was immediately cured using an electron beam irradiator EC250/15/180L manufactured by Iwasaki Electric Co., Ltd. at an acceleration voltage of 110 kV and an electron beam dose of 30 kGy to obtain a laminate having a configuration of ink layer (cured coating film)/OPP/adhesive layer/CPP.
• the obtained printed matter was cut into 9 cm x 9 cm pieces, and the three pieces were stacked so that the printed surface and the non-printed surface were in contact with each other, and the three pieces were kept for 10 days under 25 ° C and 50% environmental conditions with a load of 1 kg / dm 2. Then, the central printed matter of the three pieces was taken out and set in a migration cell so that 50 ml of 95% ethanol was in contact with the area of the non-printed surface of 0.5 dm 2. Then, the residual monomer (unreacted (meth)acrylate component) was extracted at 60 ° C for 10 days while stirring.
• the migration cell was completely sealed by the instrument, and the loss of the contents and the mixing of other components into the contents (extract) in the above process can be completely suppressed.
• the above extract was analyzed using a quadrupole time-of-flight mass spectrometer manufactured by Bruker Daltonics and an LC30A series liquid chromatograph manufactured by Shimadzu Corporation to determine the concentration of each of the (meth)acrylate compounds as the (meth)acrylate component (A) present in the ethanol.
• the migration resistance was evaluated according to the following criteria.
• the industrially practical level is "3" or higher, with "4" or higher being more preferable.
• Printing tests were carried out using the inks and varnishes obtained in Examples 1 to 29 and Comparative Examples 1 to 12.
• the printing tests were carried out on an OPP film (FOR (30 ⁇ m) manufactured by Futamura Chemical Co., Ltd.) using a Comexi CI-8 (an offset printing machine manufactured by Comexi).
• the printing speed was 200 m/min, and the EB irradiation conditions were 110 kV and 30 kGy.
• tap water containing 3.0% SUNFOUNT S27H manufactured by Sunchrmical was used as the dampening water.
• Density fluctuation is less than ⁇ 5% 4: Density fluctuation is ⁇ 5% or more but less than 10% 3: Density fluctuation is ⁇ 10% or more but less than 15% 2: Density fluctuation is ⁇ 15% or more but less than 20% 1: Density fluctuation is ⁇ 20% or more
• the present invention has been able to provide an electron beam curable composition that provides excellent adhesion to each film substrate, imparts low migration properties and transport resistance that are important in the packaging market, and is safe for health and the environment, as well as a laminate that uses the electron beam curable composition. It has also been able to provide an electron beam curable composition that has excellent printability when used as an ink.

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• Chemical & Material Sciences (AREA)
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• Polymers & Plastics (AREA)
• Wood Science & Technology (AREA)
• Engineering & Computer Science (AREA)
• Health & Medical Sciences (AREA)
• Chemical Kinetics & Catalysis (AREA)
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