Classifications

• • 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
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41J—TYPEWRITERS; SELECTIVE PRINTING MECHANISMS, i.e. MECHANISMS PRINTING OTHERWISE THAN FROM A FORME; CORRECTION OF TYPOGRAPHICAL ERRORS
  • B41J2/00—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed
  • B41J2/005—Typewriters or selective printing mechanisms characterised by the printing or marking process for which they are designed characterised by bringing liquid or particles selectively into contact with a printing material
  • B41J2/01—Ink jet
  • B41J2/21—Ink jet for multi-colour printing
  • B41J2/2107—Ink jet for multi-colour printing characterised by the ink properties
  • B41J2/2114—Ejecting specialized liquids, e.g. transparent or processing liquids
  • B41J2/2117—Ejecting white liquids
• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
  • B41M—PRINTING, DUPLICATING, MARKING, OR COPYING PROCESSES; COLOUR PRINTING
  • B41M7/00—After-treatment of prints, e.g. heating, irradiating, setting of the ink, protection of the printed stock
  • B41M7/0081—After-treatment of prints, e.g. heating, irradiating, setting of the ink, protection of the printed stock using electromagnetic radiation or waves, e.g. ultraviolet radiation, electron beams
• • 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
  • C09D11/30—Inkjet printing inks
  • C09D11/32—Inkjet printing inks characterised by colouring agents
  • C09D11/322—Pigment inks
• • 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
  • C09D11/30—Inkjet printing inks
  • C09D11/38—Inkjet printing inks characterised by non-macromolecular additives other than solvents, pigments or dyes
• • 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
  • C09D11/30—Inkjet printing inks
  • C09D11/40—Ink-sets specially adapted for multi-colour inkjet printing

Definitions

• the present disclosure relates to an electron beam curing inkjet ink, an ink set, and an image recording method.
• an image recording method in which an image is obtained by applying ink to a base material and irradiating the applied ink with active energy rays such as ultraviolet rays to cure the ink. .
• Patent Document 1 a curable composition containing a polymerizable compound is applied onto a recording medium as a cured film forming method capable of obtaining a cured film having excellent adhesion to a substrate and a small amount of residual monomer. and an irradiation step of irradiating the curable composition with two or more active energy rays, wherein at least an electron beam with an acceleration voltage of 130 kV or less is used as the active energy ray in the irradiation step.
• a cured film forming method is disclosed in which, in the irradiation step, the electron beam is irradiated so that the absorbed dose is 20 to 75 kGy.
• Patent document 1 JP 2018-86726
• the image quality (i.e., line quality) of the recorded image is excellent, and the migration (i.e., migration) of the recorded image In other words, there are cases where it is required to suppress the phenomenon that the components contained in the ink are eluted from the recorded image.
• An object to be solved by an embodiment of the present invention is to provide an electron beam-curable inkjet ink, an ink set, and an image recording method capable of recording an image with excellent image quality and suppressing migration in the recorded image. to provide.
• the present disclosure includes the following aspects. ⁇ 1> containing a polymerization initiator (A) and a polymerizable compound (B),
• the polymerization initiator (A) contains a hydrogen abstraction type polymerization initiator having a molecular weight of 500 or more,
• the content of the polymerization initiator (A) is more than 0% by mass and 2% by mass or less with respect to the total amount of the electron beam-curable inkjet ink.
• Inkjet ink for electron beam curing for electron beam curing.
• Inkjet ink for. ⁇ 3> The electron beam-curable inkjet ink according to ⁇ 1> or ⁇ 2>, wherein the hydrogen abstraction polymerization initiator having a molecular weight of 500 or more is at least one of a thioxanthone compound and a benzophenone compound.
• ⁇ 4> Does not contain a polymerization initiator other than a hydrogen abstraction type polymerization initiator having a molecular weight of 500 or more, or Any one of ⁇ 1> to ⁇ 3>, wherein the content of the polymerization initiator other than the hydrogen abstraction type polymerization initiator having a molecular weight of 500 or more is 0.1% by mass or less with respect to the total amount of the electron beam curing inkjet ink. 1.
• the inkjet ink for electron beam curing according to one.
• ⁇ 5> The electron beam curable inkjet ink according to any one of ⁇ 1> to ⁇ 4>, wherein the hydrogen abstraction polymerization initiator having a molecular weight of 500 or more includes a hydrogen abstraction polymerization initiator having a molecular weight of 1000 or more.
• ⁇ 6> The electron beam-curable inkjet ink according to any one of ⁇ 1> to ⁇ 5>, further comprising an amine having a molecular weight of 500 or more.
• ⁇ 7> The content of the amine having a molecular weight of 500 or more is 0.1% by mass to 2% by mass with respect to the total amount of the electron beam-curable inkjet ink.
• ⁇ 8> The electron beam-curable inkjet ink according to ⁇ 6> or ⁇ 7>, wherein the amine having a molecular weight of 500 or more includes an amine having a molecular weight of 1000 or more.
• the polymerizable compound (B) includes a monofunctional polymerizable compound and a polyfunctional polymerizable compound, The content mass ratio of the monofunctional polymerizable compound to the polyfunctional polymerizable compound is 0.4 to 2.3.
• ⁇ 10> The electron beam-curable inkjet ink according to any one of ⁇ 1> to ⁇ 9>, further comprising a silicone surfactant.
• ⁇ 11> The content of the silicone-based surfactant is 1% by mass to 5% by mass with respect to the total amount of the electron beam-curable inkjet ink.
• ⁇ 12> The electron beam-curable inkjet ink according to any one of ⁇ 1> to ⁇ 11>, further comprising a pigment (C).
• the white ink which is the electron beam-curable inkjet ink according to ⁇ 12>, containing a white pigment as the pigment (C); and a colored ink containing a pigment with a hue other than white,
• An ink set in which the colored ink does not contain a polymerization initiator, or the content of the polymerization initiator is 0.1% by mass or less with respect to the total amount of the colored ink.
• the ink application step includes applying an electron beam curable inkjet ink onto the substrate and applying radiation having a wavelength of 300 nm to 395 nm to the electron beam curable inkjet ink applied onto the substrate.
• an electron beam is irradiated to the electron beam curing inkjet ink irradiated with ultraviolet X.
• the image recording method according to ⁇ 16>. ⁇ 18> An image recording method using the ink set according to ⁇ 13> or ⁇ 14>, an ink application step of sequentially applying two or more types of electron beam curing inkjet inks onto a substrate; an electron beam irradiation step of irradiating two or more types of electron beam curing inkjet inks applied on a substrate with an electron beam; including, Image recording method.
• the ink applying step one of two or more types of electron beam curing inkjet inks is applied onto the substrate, and ultraviolet X rays containing radiation having a wavelength of 300 nm to 395 nm are applied to the applied one type.
• the operation of irradiating is sequentially performed one by one for two or more electron beam curing inkjet inks, The image recording method according to ⁇ 18>.
• the ink set is a white ink that is an electron beam-curable inkjet ink containing a white pigment as the pigment (C); a colored ink that is an electron beam-curable inkjet ink containing a pigment (C) having a hue other than white; including
• the white ink and the colored ink are applied in this order, and from the dynamic surface tension ⁇ of the white ink 500 ⁇ s after the application of the white ink, the dynamic surface of the colored ink 500 ⁇ s after the application of the colored ink
• the value after subtracting the tension ⁇ is greater than 1 mN / m,
• the image recording method according to ⁇ 18> or ⁇ 19>.
• the ink set is a white ink that is an electron beam-curable inkjet ink containing a white pigment as the pigment (C); two or more colored inks that are electron beam-curable inkjet inks containing a pigment (C) having a hue other than white; including
• white ink is applied and then two or more colored inks are sequentially applied,
• n is an integer of 2 or more
• from the dynamic surface tension ⁇ (n) of the n-th applied coloring ink 500 ⁇ s after application the n + 1-th coloring ink applied 500 ⁇ s after application
• the absolute value of the value after subtracting the dynamic surface tension ⁇ (n + 1) is 1 mN / m or less.
• an electron beam-curable inkjet ink an ink set, and an image recording method that can record an image with excellent image quality and suppress migration in the recorded image.
• a numerical range represented using “to” means a range including the numerical values described before and after “to” as lower and upper limits.
• the amount of each component in the composition means the total amount of the above substances present in the composition unless otherwise specified when there are multiple substances corresponding to each component in the composition. do.
• the upper or lower limit value described in a certain numerical range may be replaced with the upper or lower limit value of another numerical range described step by step, Alternatively, the values shown in the examples may be substituted.
• the term "process” includes not only independent processes, but also processes that cannot be clearly distinguished from other processes, as long as the intended purpose of the process is achieved.
• (meth)acrylate is a concept that includes both acrylate and methacrylate
• (meth)acryloyl group is a concept that includes both an acryloyl group and a methacryloyl group
• (meth) "Acrylic acid” is a concept that includes both acrylic acid and methacrylic acid.
• image means a film formed using ink in general
• image recording means formation of an image (that is, film).
• image in the present disclosure includes a solid image.
• the electron beam curing inkjet ink of the present disclosure (hereinafter also simply referred to as “ink”) containing a polymerization initiator (A) and a polymerizable compound (B),
• the polymerization initiator (A) contains a hydrogen abstraction type polymerization initiator having a molecular weight of 500 or more,
• the content of the polymerization initiator (A) is more than 0% by mass and 2% by mass or less with respect to the total amount of the ink.
• the ink of the present disclosure contains a hydrogen abstraction type polymerization initiator having a molecular weight of 500 or more as a polymerization initiator.
• a hydrogen abstraction type polymerization initiator having a molecular weight of 500 or more as a polymerization initiator.
• the content of the polymerization initiator (A) (that is, the total content of polymerization initiators contained in the ink) is limited to 2% by mass or less with respect to the total amount of the ink. .
• an increase in the viscosity of the ink is suppressed, and a decrease in the ejection performance (more specifically, the ejection performance from the inkjet head; the same shall apply hereinafter) due to the increase in the viscosity of the ink is suppressed.
• the image quality that is, line quality
• the ink of the present disclosure is particularly suitable for image recording on food packaging materials, for example, because it exhibits the above effects (in particular, suppression of migration). Being able to further suppress migration is advantageous in that the odor of the image can be suppressed.
• the application of the ink of the present disclosure is not limited to image recording on food packaging materials.
• the ink of the present disclosure contains a polymerization initiator (A).
• the content of the polymerization initiator (A) is more than 0% by mass and 2% by mass or less with respect to the total amount of the ink.
• the polymerization initiator (A) means all polymerization initiators that can be contained in the ink
• the content of the polymerization initiator (A) means the total amount of all polymerization initiators that can be contained in the ink. means content.
• the content of the polymerization initiator (A) is more than 0% by mass, the curability of the ink against electron beam irradiation (that is, the polymerizability of the polymerizable compound (B)) is ensured.
• the content of the polymerization initiator (A) can be less than when the ink is cured by ultraviolet irradiation.
• the content of the polymerization initiator (A) is preferably 0.1% by mass or more, more preferably 0.3% by mass. Preferably, it is 0.6% by mass or more.
• the content of the polymerization initiator (A) is 2% by mass or less, migration is suppressed. From the viewpoint of further suppressing migration, the content of the polymerization initiator (A) is preferably 1.5% by mass or less.
• a preferred range for the content of the polymerization initiator (A) is 0.1% by mass to 2% by mass.
• the polymerization initiator (A) contains a hydrogen abstraction type polymerization initiator having a molecular weight of 500 or more.
• the fact that the molecular weight is 500 or more contributes to the effect of suppressing migration.
• the fact that it is a hydrogen abstraction type contributes to curability against electron beam irradiation.
• the preferred range of the content of the hydrogen abstraction type polymerization initiator having a molecular weight of 500 or more relative to the total amount of ink is the same as the preferred range of the content of the polymerization initiator (A) relative to the total amount of ink.
• the polymerization initiator (A) in the ink may consist only of a hydrogen abstraction polymerization initiator having a molecular weight of 500 or more, or may be composed of a hydrogen abstraction polymerization initiator having a molecular weight of 500 or more and another polymerization initiator. may include.
• the content (% by mass) of the hydrogen abstraction type polymerization initiator having a molecular weight of 500 or more relative to the total amount of the ink need not be the same value as the content (% by mass) of the polymerization initiator (A) relative to the total amount of the ink. .
• a preferred range for the content of the hydrogen abstraction type polymerization initiator having a molecular weight of 500 or more is 0.1% by mass to 2% by mass.
• the proportion of the hydrogen abstraction type polymerization initiator having a molecular weight of 500 or more in the polymerization initiator (A) is preferably 50% by mass to 100% by mass, more preferably 60% by mass to 100% by mass, and still more preferably. is 80% by mass to 100% by mass.
• the proportion of the hydrogen abstraction type polymerization initiator having a molecular weight of 500 or more in the polymerization initiator (A) may be 100% by mass. That is, the polymerization initiator (A) may not contain a polymerization initiator other than a hydrogen abstraction type polymerization initiator having a molecular weight of 500 or more.
• the content of the polymerization initiator other than the hydrogen abstraction type polymerization initiator having a molecular weight of 500 or more is preferably 0.1% by mass or less with respect to the total amount of the ink.
• the molecular weight of the hydrogen abstraction type polymerization initiator having a molecular weight of 500 or more is preferably 700 or more, more preferably 800 or more, still more preferably 1000 or more.
• the upper limit of the molecular weight of the hydrogen abstraction polymerization initiator having a molecular weight of 500 or more is preferably 5,000, more preferably 4,000, and still more preferably 3,000.
• the hydrogen abstraction polymerization initiator having a molecular weight of 500 or more preferably contains a hydrogen abstraction polymerization initiator having a molecular weight of 1000 or more.
• a hydrogen abstraction polymerization initiator having a molecular weight of 1000 or more and a hydrogen abstraction polymerization initiator having a molecular weight of 500 or more and less than 100 may be used together.
• the ratio of the hydrogen abstraction type polymerization initiator with a molecular weight of 1000 or more in the hydrogen abstraction type polymerization initiator with a molecular weight of 500 or more is preferably 50% by mass to 100% by mass, more preferably 60% by mass to 100% by mass. and more preferably 80% by mass to 100% by mass.
• At least one of a thioxanthone compound and a benzophenone compound is preferable as the hydrogen abstraction type polymerization initiator having a molecular weight of 500 or more.
• the thioxanthone compound as a hydrogen abstraction polymerization initiator having a molecular weight of 500 or more include compounds represented by the following formula (S1).
• the benzophenone compound as a hydrogen abstraction polymerization initiator having a molecular weight of 500 or more include compounds represented by the following formula (S2).
• R 1 , R 2 , R 3 and R 4 each independently represent an alkyl group having 1 to 5 carbon atoms or a halogen atom, and x and y each independently represent , represents an integer of 2 to 4, j and m each independently represents an integer of 0 to 4, k and n each independently represents an integer of 0 to 3, j, k, m and n are 2
• the integer is 0 or more
• the plurality of R 1 , R 2 , R 3 and R 4 may be the same or different
• X 1 is an x-valent containing at least one of a hydrocarbon chain, an ether bond, and an ester bond
• X2 represents a y - valent linking group containing at least one of a hydrocarbon chain, an ether bond, and an ester bond.
• a commercially available compound can also be used as the compound represented by formula (S1).
• Speedcure® 7010 (1,3-di( ⁇ -[1-chloro-9-oxo-9H-thioxanthen-4-yl]oxy ⁇ acetylpoly[oxy(1-methylethylene)]oxy) manufactured by Lambson -2,2-bis( ⁇ -[1-chloro-9-oxo-9H-thioxanthen-4-yl]oxy ⁇ acetylpoly[oxy(1-methylethylene)]oxymethyl)propane, CAS No. 1003567-83-6 ); IGM Resins B.I. V.
• OMNIPOL® TX Polybutyleneglycol bis(9-oxo-9H-thioxanthenyloxy)acetate, CAS No. 813452-37-8) manufactured by Ran A. G. Genopo TX-2 manufactured by Co.; etc. are exemplified.
• a commercially available compound can also be used as the compound represented by formula (S2). Specifically, IGM Resins B.V. V. OMNIPOL BP (Polybutyleneglycol bis(4-benzoylphenoxy)acetate, CAS No. 515136-48-8) manufactured by the company is exemplified.
• the ink of the present disclosure contains a polymerizable compound (B).
• the polymerizable compound (B) means all polymerizable compounds that can be contained in the ink, and may be one polymerizable compound or two or more polymerizable compounds.
• the polymerizable compound is not particularly limited as long as it is a compound containing a polymerizable group.
• an ethylenically unsaturated group is preferred.
• the ethylenically unsaturated group is preferably a (meth)acryloyl group, a vinyl group, an allyl group, or a styryl group, more preferably a (meth)acryloyl group or a vinyl group.
• the molecular weight of the polymerizable compound is not particularly limited, it is preferably 5,000 or less, more preferably 2,000 or less, still more preferably 1,500 or less, and even more preferably 1,000 or less.
• the lower limit of the molecular weight of the polymerizable compound is, for example, 58 (molecular weight of methyl vinyl ether).
• the polymerizable compound (B) may be a monofunctional polymerizable compound (i.e., a compound containing only one polymerizable group) or a polyfunctional polymerizable compound (i.e., a polymerizable group containing two or more compound), or both a monofunctional polymerizable compound and a polyfunctional polymerizable compound.
• a monofunctional polymerizable compound i.e., a compound containing only one polymerizable group
• a polyfunctional polymerizable compound i.e., a polymerizable group containing two or more compound
• both a monofunctional polymerizable compound and a polyfunctional polymerizable compound i.e., a polymerizable group containing two or more compound
• a bifunctional polymerizable compound i.e., a compound containing two polymerizable groups
• a trifunctional polymerizable compound i.e., polymerized compounds containing three functional groups
• the polymerizable compound (B) preferably contains at least one of a monofunctional polymerizable compound and a bifunctional polymerizable compound, and more preferably contains both a monofunctional polymerizable compound and a bifunctional polymerizable compound. preferable.
• the polymerizable compound (B) contains at least one of a monofunctional polymerizable compound and a difunctional polymerizable compound, the total amount of the monofunctional polymerizable compound and the bifunctional polymerizable compound in the total amount of the ink The proportion is preferably 50% by mass or more, more preferably 60% by mass or more, and even more preferably 80% by mass or more.
• the polymerizable compound (B) preferably contains a monofunctional polymerizable compound and a polyfunctional polymerizable compound (preferably a bifunctional polymerizable compound).
• the content mass ratio of the monofunctional polymerizable compound to the polyfunctional polymerizable compound (hereinafter also referred to as "monofunctional/polyfunctional ratio" or "monofunctional/polyfunctional”) is 0.2 to 2.0. It is preferably 5, preferably 0.4 to 2.3.
• the monofunctional/polyfunctional ratio is 0.2 or more, image quality and/or adhesion are further improved.
• the monofunctional/polyfunctional ratio is 2.5 or less, migration is further suppressed.
• polymerizable compound (B) Specific examples of the polymerizable compound (B) are shown below, but the polymerizable compound (B) is not limited to the following specific examples.
• monofunctional polymerizable compounds include monofunctional (meth)acrylates, monofunctional (meth)acrylamides, monofunctional aromatic vinyl compounds, monofunctional vinyl ethers, monofunctional N-vinyl compounds, and the like.
• Examples of monofunctional (meth)acrylates include methyl (meth)acrylate, ethyl (meth)acrylate, propyl (meth)acrylate, n-butyl (meth)acrylate, hexyl (meth)acrylate, and 2-ethylhexyl (meth)acrylate.
• tert-octyl (meth)acrylate isoamyl (meth)acrylate, decyl (meth)acrylate, isodecyl (meth)acrylate, lauryl (meth)acrylate, stearyl (meth)acrylate, isostearyl (meth)acrylate, cyclohexyl (meth)acrylate acrylates, 4-n-butylcyclohexyl (meth)acrylate, 4-tert-butylcyclohexyl (meth)acrylate, bornyl (meth)acrylate, norbornyl (meth)acrylate, isobornyl (meth)acrylate, adamantyl (meth)acrylate, 2 - ethylhexyl diglycol (meth)acrylate, butoxyethyl (meth)acrylate, 2-chloroethyl (meth)acrylate, 4-bromobutyl (meth)acrylate, cyan
• Examples of monofunctional (meth)acrylamides include (meth)acrylamide, N-methyl(meth)acrylamide, N-ethyl(meth)acrylamide, N-propyl(meth)acrylamide, Nn-butyl(meth)acrylamide, Nt-butyl (meth)acrylamide, N-butoxymethyl (meth)acrylamide, N-isopropyl (meth)acrylamide, N-methylol (meth)acrylamide, N,N-dimethyl (meth)acrylamide, N,N-diethyl (meth)acrylamide, (meth)acryloylmorpholine, and the like.
• monofunctional aromatic vinyl compounds include styrene, dimethylstyrene, trimethylstyrene, isopropylstyrene, chloromethylstyrene, methoxystyrene, acetoxystyrene, chlorostyrene, dichlorostyrene, bromostyrene, vinylbenzoic acid methyl ester, 3-methyl Styrene, 4-methylstyrene, 3-ethylstyrene, 4-ethylstyrene, 3-propylstyrene, 4-propylstyrene, 3-butylstyrene, 4-butylstyrene, 3-hexylstyrene, 4-hexylstyrene, 3-octyl Styrene, 4-octylstyrene, 3-(2-ethylhexyl)styrene, 4-(2-ethylhexyl)styrene
• Monofunctional vinyl ethers include, for example, methyl vinyl ether, ethyl vinyl ether, propyl vinyl ether, n-butyl vinyl ether, t-butyl vinyl ether, 2-ethylhexyl vinyl ether, n-nonyl vinyl ether, lauryl vinyl ether, cyclohexyl vinyl ether, cyclohexylmethyl vinyl ether, 4-methyl Cyclohexyl methyl vinyl ether, benzyl vinyl ether, dicyclopentenyl vinyl ether, 2-dicyclopentenoxyethyl vinyl ether, methoxyethyl vinyl ether, ethoxyethyl vinyl ether, butoxyethyl vinyl ether, methoxyethoxyethyl vinyl ether, ethoxyethoxyethyl vinyl ether, methoxypolyethylene glycol vinyl ether, tetrahydro Furfuryl vinyl ether, 2-hydroxyethyl vinyl ether, 2-hydroxy
• Examples of monofunctional N-vinyl compounds include N-vinylcaprolactam, N-vinylpyrrolidone, N-vinyloxazolidinone, N-vinyl-5-methyloxazolidinone and the like.
• the monofunctional polymerizable compound preferably contains at least one of a monofunctional (meth)acrylate and a monofunctional N-vinyl compound, and a monofunctional (meth)acrylate containing an alicyclic structure and a monofunctional N-vinyl compound. It is more preferable to include at least one.
• the monofunctional (meth)acrylate containing an alicyclic structure is preferably isobornyl (meth)acrylate, norbornyl (meth)acrylate, or adamantyl (meth)acrylate, more preferably isobornyl (meth)acrylate.
• the total ratio of monofunctional (meth)acrylate (preferably monofunctional (meth)acrylate containing an alicyclic structure) and monofunctional N-vinyl compound in the monofunctional polymerizable compound is 50% by mass to 100% by mass. %, more preferably 60% by mass to 100% by mass, even more preferably 80% by mass to 100% by mass.
• the proportion of the monofunctional N-vinyl compound in the monofunctional polymerizable compound is preferably 20% by mass or more, more preferably 30% by mass or more, and even more preferably 50% by mass or more. .
• bifunctional polymerizable compounds include bifunctional (meth)acrylates, bifunctional vinyl ethers, bifunctional monomers containing a vinyl ether group and a (meth)acryloyl group, and the like.
• bifunctional (meth)acrylates include ethylene glycol di(meth)acrylate, diethylene glycol di(meth)acrylate, triethylene glycol di(meth)acrylate, propylene glycol di(meth)acrylate, and dipropylene glycol di(meth)acrylate.
• acrylates tripropylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, polypropylene glycol di(meth)acrylate, butylene glycol di(meth)acrylate, tetraethylene glycol di(meth)acrylate, neopentyl glycol di(meth)acrylate ) acrylate, 3-methyl-1,5-pentanediol di(meth)acrylate, hexanediol di(meth)acrylate, heptanediol di(meth)acrylate, EO-modified neopentyl glycol di(meth)acrylate, PO-modified neopentyl Glycol di(meth)acrylate, EO-modified hexanediol di(meth)acrylate, PO-modified hexanediol di(meth)acrylate, octanediol di(meth)acrylate,
• bifunctional vinyl ethers examples include 1,4-butanediol divinyl ether, ethylene glycol divinyl ether, diethylene glycol divinyl ether, triethylene glycol divinyl ether, polyethylene glycol divinyl ether, propylene glycol divinyl ether, butylene glycol divinyl ether, hexanediol divinyl ether.
• bifunctional polymerizable compounds containing a vinyl ether group and a (meth)acryloyl group examples include 2-(2-vinyloxyethoxy)ethyl (meth)acrylate.
• tri- or higher functional polymerizable compounds include tri- or higher functional (meth)acrylates, tri- or higher functional vinyl ethers, and the like.
• Tri- or higher functional (meth)acrylates include, for example, trimethylolethane tri(meth)acrylate, trimethylolpropane tri(meth)acrylate, EO-modified trimethylolpropane tri(meth)acrylate, PO-modified trimethylolpropane tri(meth)acrylate, ) acrylate, pentaerythritol tri(meth)acrylate, pentaerythritol tetra(meth)acrylate, dipentaerythritol tetra(meth)acrylate, dipentaerythritol penta(meth)acrylate, dipentaerythritol hexa(meth)acrylate, tri(meth)acrylate acryloyloxyethoxytrimethylolpropane, glycerin polyglycidyl ether poly(meth)acrylate, tris(2-acryloyloxyethyl)isocyanurate, and the like
• tri- or higher functional vinyl ethers examples include trimethylolethane trivinyl ether, trimethylolpropane trivinyl ether, ditrimethylolpropane tetravinyl ether, glycerin trivinyl ether, pentaerythritol tetravinyl ether, dipentaerythritol pentavinyl ether, dipentaerythritol hexavinyl ether, and EO.
• Modified trimethylolpropane trivinyl ether PO-modified trimethylolpropane trivinyl ether, EO-modified ditrimethylolpropane tetravinyl ether, PO-modified ditrimethylolpropane tetravinyl ether, EO-modified pentaerythritol tetravinyl ether, PO-modified pentaerythritol tetravinyl ether, EO-modified dipentaerythritol hexavinyl ether, PO-modified dipentaerythritol hexavinyl ether, and the like.
• Urethane (meth)acrylates include urethane (meth)acrylates that are reaction products of bifunctional isocyanate compounds and hydroxyl group-containing (meth)acrylates.
• bifunctional isocyanate compounds include methylene diisocyanate, dimethylene diisocyanate, trimethylene diisocyanate, tetramethylene diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate, dipropyl ether diisocyanate, 2,2-dimethylpentane diisocyanate, 3-methoxyhexane diisocyanate, octamethylene diisocyanate, 2,2, Aliphatic diisocyanates such as 4-trimethylpentane diisocyanate, nonamethylene diisocyanate, decamethylene diisocyanate, 3-butoxyhexane diisocyanate, 1,4-butylene glycol dipropyl ether diisocyanate, thiodihexyl diisocyanate; m-phenylene diisocyanate, p-phenylene diisocyanate, 2,4-tolylene diisocyanate, 2,6-tolylene diis
• hydroxyl group-containing (meth)acrylates examples include 2-hydroxyethyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 2-hydroxybutyl (meth)acrylate, 3-hydroxy Butyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, phenylglycidyl ether (meth)acrylate, pentaerythritol (meth)triacrylate, dipentaerythritol penta(meth)acrylate, and the like.
• epoxy (meth)acrylate is a reaction in which a carboxy group in (meth)acrylic acid reacts with two or three epoxy groups in an epoxy compound containing two or three epoxy groups. means product. Therefore, epoxy groups are not included in the structure of epoxy (meth)acrylate. In this respect, the epoxy (meth)acrylate is different from the epoxy compound, which is an example of the cationic polymerizable monomer described above.
• Epoxy (meth)acrylates include reaction products of (meth)acrylic acid and epoxy resins.
• epoxy resins include bisphenol A type epoxy resins, cresol novolac type epoxy resins, and the like.
• the ink of the present disclosure may contain pigment (C). That is, the ink of the present disclosure may be a clear ink containing no pigment (C).
• the pigment (C) means all pigments that can be contained in the ink, and may be one type of pigment or two or more types of pigments.
• the pigment can be included in the ink as a pigment dispersion.
• a pigment dispersion is a liquid obtained by dispersing a pigment in a liquid medium using a dispersant, and contains at least a pigment, a dispersant, and a liquid medium. When a self-dispersing pigment is used as the pigment, the ink does not need to contain a dispersant.
• Liquid media include, for example, organic solvents. Further, the liquid medium may be the polymerizable compound contained in the ink.
• the pigment may be either an organic pigment or an inorganic pigment that is commonly available on the market. Also, the pigment may be an invisible pigment having infrared absorbability.
• the content of the pigment (C) (that is, the total content of pigments contained in the ink) is preferably 1% by mass to 20% by mass, more preferably 2% by mass to 10% by mass, relative to the total amount of the ink. It is more preferable to have
• the ink of the present disclosure may contain at least one dispersant for dispersing the pigment (C).
• the dispersant As the dispersant, a commonly known one can be used. From the viewpoint of dispersion stability, the dispersant is preferably a compound having both a hydrophilic structure and a hydrophobic structure.
• Dispersants include, for example, higher fatty acid salts, alkyl sulfates, alkyl ester sulfates, alkyl sulfonates, sulfosuccinates, naphthalene sulfonates, alkyl phosphates, polyoxyalkylene alkyl ether phosphates, polyoxy Low molecular weight dispersants having a molecular weight of less than 1000, such as alkylene alkylphenyl ether, polyoxyethylene polyoxypropylene glycol, glycerin fatty acid ester, sorbitan fatty acid ester, polyoxyethylene fatty acid amide, and amine oxide.
• examples of dispersants include high molecular weight dispersants having a molecular weight of 1000 or more obtained by copolymerizing a hydrophilic monomer and a hydrophobic monomer.
• the hydrophilic monomer is preferably a dissociative group-containing monomer, and preferably a dissociative group-containing monomer having a dissociative group and an ethylenically unsaturated bond.
• examples of dissociable group-containing monomers include carboxy group-containing monomers, sulfonic acid group-containing monomers, and phosphoric acid group-containing monomers.
• the hydrophobic monomer is an aromatic group-containing monomer having an aromatic group and an ethylenically unsaturated bond, or an aliphatic hydrocarbon having an aliphatic hydrocarbon group and an ethylenically unsaturated bond.
• Group-containing monomers are preferred.
• the polymer may be either a random copolymer or a block copolymer.
• Dispersants may be commercially available.
• Commercially available products include, for example, DISPERBYK-101 DISPERBYK-102 DISPERBYK-103 DISPERBYK-106 DISPERBYK-110 DISPERBYK-111 DISPERBYK-161 DISPERBYK-162 DISPERBYK-163 DISPERBYK-164 168 ⁇ DISPERBYK-170 ⁇ DISPERBYK-171 ⁇ DISPERBYK-174 ⁇ DISPERBYK-182(BYK ⁇ ); ⁇ SOLSPERSE3000 ⁇ SOLSPERSE5000 ⁇ SOLSPERSE9000 ⁇ SOLSPERSE12000 ⁇ SOLSPERSE13240 ⁇ SOLSPERSE13940 ⁇ SOLSPERSE17000 ⁇ SOLSPERSE22000 ⁇ SOLSPERSE24000 ⁇ SOLSPERSE26000 ⁇ SOLSPERSE28000 ⁇ SOLSPERSE32000 ⁇ SOLSPERSE36000 , SOLSPERSE39000, SOLSPERSE41000, SOLSPERSE71000 (man
• dispersing device for dispersing the pigment
• known dispersing devices can be used, for example, ball mills, sand mills, bead mills, roll mills, jet mills, paint shakers, attritors, ultrasonic dispersers and dispersers.
• the ratio of the content of the dispersant to the content of the pigment is 0.05 to 1.0 on a mass basis from the viewpoint of dispersion stability. is preferred, and 0.1 to 0.8 is more preferred.
• the ink of the present disclosure preferably further contains at least one amine having a molecular weight of 500 or more.
• the content of the amine having a molecular weight of 500 or more is preferably more than 0% by mass and 2% by mass or less with respect to the total amount of the ink.
• the content of amine having a molecular weight of 500 or more is 2% by mass or less, migration is further suppressed.
• the content of amines having a molecular weight of 500 or more is preferably 1.5% by mass or less.
• a preferred range for the content of amines with a molecular weight of 500 or more is 0.1% by mass to 2% by mass.
• the amine having a molecular weight of 500 or more is not particularly limited as long as it contains an amino group (that is, contains at least one of an unsubstituted amino group and a substituted amino group) and has a molecular weight of 500 or more.
• Examples of amines having a molecular weight of 500 or more include compounds represented by the following formula (X).
• R 1 , R 2 and R 3 each independently represent a hydrogen atom or a substituent. However, R 1 , R 2 and R 3 are selected so that the molecular weight of the compound represented by formula (X) is 500 or more. ]
• R 1 , R 2 and R 3 are preferably substituents, and all three of R 1 , R 2 and R 3 are substituents. More preferred. It is also a preferred embodiment that R 1 , R 2 and R 3 contain a (meth)acryloyloxy group.
• Amines with a molecular weight of 500 or more contain at least one amino group, but from the viewpoint of viscosity and migration suppression, the amines with a molecular weight of 500 or more preferably contain 1 to 6 amino groups, and 1 to 3 amino groups. More preferably, it contains 1 or 2 amino groups.
• the amine having a molecular weight of 500 or more contains a (meth)acryloyloxy group
• the amine having a molecular weight of 500 or more preferably contains 1 to 6 (meth)acryloyl groups. It more preferably contains 1 to 4 (meth)acryloyl groups, even more preferably 1 or 2 (meth)acryloyl groups.
• a commercially available product may be used as the amine having a molecular weight of 500 or more.
• Examples of commercially available amines having a molecular weight of 500 or more include: GENOMER5161, GENOMER5271, GENOMER5275, GENOMER5795 (above, RAHN); CN371, CN373, CN383, CN384, CN386, CN501, CN550, CN551 (above, Sartomer); EBECRYL7100, EBECRYL80, EBECRYL81, EBECRYL83, EBECRYL84, EBECRYLP115 (the above, Daicel Cytec); Laromer PO77F (LR8946), Laromer LR8956, Laromer LR8996, Laromer PO94F (LR8894) (above, BASF); Photomer4771, Photomer4775, Photomer4967, Photomer5006, Photomer5096, Photomer5662, Photomer5930 (abo
• the molecular weight of the amine having a molecular weight of 500 or more is preferably 700 or more, more preferably 800 or more, still more preferably 1000 or more, from the viewpoint of further suppressing migration.
• the upper limit of the molecular weight of the amine having a molecular weight of 500 or more is preferably 10,000, more preferably 7,000, still more preferably 5,000.
• the amine having a molecular weight of 500 or more preferably contains an amine having a molecular weight of 1000 or more.
• an amine having a molecular weight of 1000 or more and an amine having a molecular weight of 500 or more and less than 100 may be used together.
• the proportion of amines with a molecular weight of 1000 or more in the amines with a molecular weight of 500 or more is preferably 50% by mass to 100% by mass, more preferably 60% by mass to 100% by mass, and still more preferably 80% by mass to 100% by mass.
• the ink of the present disclosure preferably further contains at least one silicone surfactant.
• the silicone-based surfactant is a surfactant containing a siloxane structure.
• silicone surfactants include BYK-UV3500, 3505, 3510, 3530, 3570, 3575, 3576, 3760, 378, 375, 306, 333, 377, 330, 307, 342, 302, 300, 331, 325, 320, 315N, 326, 322 (manufactured by BYK); TEGORad 2100, 2200, 2250, 2300, 2500, 2600, 2700, 2010; , 435, 440, 450, 482, A115, B1484, ZG400; and TEGOFlow 300, 370, 425, ATF2, ZFS 460 (manufactured by Evonik).
• the content of the silicone-based surfactant is preferably 0.1% by mass or more, more preferably 0.3% by mass or more, and still more preferably 1% by mass or more, relative to the total amount of the ink.
• the upper limit of the content of the silicone-based surfactant is preferably 10% by mass, more preferably 5% by mass, relative to the total amount of the ink.
• the ink of the present disclosure may further contain at least one surfactant other than the silicone surfactant.
• the type of other surfactant is not particularly limited, and may be an anionic surfactant, a cationic surfactant, or a nonionic surfactant.
• Other surfactants include, for example, acrylic surfactants and fluorine-based surfactants.
• Acrylic surfactants are surfactants containing structures derived from acrylic monomers.
• acrylic surfactants include BYK361N, BYK350, BYK356, and BYK-UV3535 (manufactured by BYK).
• a fluorosurfactant is a surfactant containing a perfluoroalkyl group.
• fluorosurfactants include Megafac F-114, F-251, F-253, F-281, F-410, F-477, F-510, F-551, F-552, F- 553, F-554, F-555, F-556, F-557, F-558, F-559, F-560, F-561, F-562, F-563, F-565, F-568, F-569, F-570, F-572, F-574, F-575, F-576, R-40, R-40-LM, R-41, R-94, RS-56, RS-72- K, RS-75, RS-76-E, RS-76-NS, RS-78, RS-90, and DS-21 (manufactured by DIC Corporation).
• the ink of the present disclosure may contain other components other than the components described above, if necessary.
• Other components include, for example, sensitizers, co-sensitizers, polymerization inhibitors, ultraviolet absorbers, antioxidants, anti-fading agents, conductive salts, organic solvents, and basic compounds.
• the pH of the ink is preferably from 7 to 10, more preferably from 7.5 to 9.5, from the viewpoint of improving ejection properties when applied by an inkjet method.
• the pH is measured at 25° C. using a pH meter, for example, using a pH meter manufactured by DKK Toa (model number “HM-31”).
• the viscosity of the ink is preferably 0.5 mPa ⁇ s to 30 mPa ⁇ s, more preferably 2 mPa ⁇ s to 20 mPa ⁇ s, preferably 2 mPa ⁇ s to 15 mPa ⁇ s, and 3 mPa ⁇ s. More preferably, it is up to 10 mPa ⁇ s. Viscosity is measured at 25° C. using a viscometer, for example, using a TV-22 viscometer manufactured by Toki Sangyo Co., Ltd.
• the surface tension of the ink is preferably 60 mN/m or less, more preferably 20 mN/m to 50 mN/m, even more preferably 25 mN/m to 45 mN/m.
• the surface tension is measured at 25° C. using a surface tensiometer, for example, by a plate method using an automatic surface tensiometer manufactured by Kyowa Interface Science Co., Ltd. (product name “CBVP-Z”).
• the ink set of the present disclosure is preferably an ink set containing two or more of the inks of the present disclosure described above. Since the first aspect of the ink set of the present disclosure contains the ink of the present disclosure, the same effect as the ink of the present disclosure (that is, it is possible to record an image with excellent image quality and prevent migration in the recorded image). effect of being able to suppress it).
• An ink set containing two or more inks of the present disclosure includes a combination of the ink of the present disclosure that does not contain the pigment (C) and one or more inks of the present disclosure that contain the pigment (C); Combinations of two or more of the inks of the present disclosure, including
• two or more of the inks of the present disclosure containing the pigment (C) are used to record multicolor images with excellent image quality and suppressed migration. can.
• the pigment (C) preferably differs in hue between the two or more inks of the present disclosure. That is, in the ink set of the present disclosure, preferably the two or more inks of the present disclosure have different hues.
• the two or more inks included in the ink set of the present disclosure are white ink (for example, white ink containing a white pigment as pigment (C)), black ink (for example, a black ink containing a black pigment as the pigment (C), a composite black ink containing a combination of a cyan pigment, a magenta pigment, and a yellow pigment as the pigment (C), etc.), cyan ink (for example, cyan ink containing a cyan pigment as pigment (C)), Magenta ink (for example, magenta ink containing magenta pigment as pigment (C)) and yellow ink (for example, yellow ink containing yellow pigment as pigment (C)) It is preferable to include two or more selected from the group consisting of The ink set in this case may further contain inks of other colors as required.
• each of the two or more inks in the ink set of the present disclosure contains a silicone-based surfactant.
• the preferable range of the content of the silicone-based surfactant with respect to the total amount of each ink is as described above (for example, 1% by mass to 5% by mass with respect to the total amount of the ink).
• the ink set of the present disclosure may contain at least one liquid other than two or more of the inks of the present disclosure.
• Other liquids include inks other than the inks of the present disclosure, undercoat liquids, overcoat liquids, maintenance liquids, and the like.
• the ink set of the present disclosure includes, as a second aspect, the ink of the present disclosure described above and a colored ink containing a pigment, and the colored ink does not contain a polymerization initiator or contains a polymerization initiator.
• the amount is preferably 0.1% by mass or less with respect to the total amount of the colored ink.
• the ink set of the present disclosure includes a white ink, which is the ink of the present disclosure described above, which contains a white pigment as the pigment (C), and a colored ink containing a pigment of a hue other than white, wherein the colored ink is It is preferable that the ink does not contain a polymerization initiator, or that the content of the polymerization initiator is 0.1% by mass or less with respect to the total amount of the colored ink.
• the second aspect of the ink set of the present disclosure contains the ink of the present disclosure, the same effect as the ink of the present disclosure (that is, it is possible to record an image with excellent image quality and prevent migration in the recorded image). effect of being able to suppress it).
• the colored ink preferably contains a pigment with a hue other than white.
• Pigments with hues other than white include, for example, black pigments, cyan pigments, magenta pigments, and yellow pigments.
• the number of colored inks included in the ink set of the present disclosure may be one, or two or more.
• the colored ink preferably contains a polymerizable compound in addition to the pigment.
• Preferred aspects of the polymerizable compound contained in the colored ink are the same as preferred aspects of the polymerizable compound (B) contained in the ink of the present disclosure.
• the colored ink preferably further contains a silicone-based surfactant.
• Preferred aspects of the silicone-based surfactant contained in the colored ink are the same as preferred aspects of the silicone-based surfactant contained in the ink of the present disclosure.
• the colored ink does not contain a polymerization initiator, or that the content of the polymerization initiator is 0.1% by mass or less with respect to the total amount of the colored ink.
• the colored ink may contain other components than the above components, if necessary.
• Other components include, for example, sensitizers, co-sensitizers, polymerization inhibitors, ultraviolet absorbers, antioxidants, anti-fading agents, conductive salts, organic solvents, and basic compounds.
• the image recording method of the present disclosure is an image recording method using the ink of the present disclosure described above, an ink application step of applying the ink of the present disclosure onto a substrate; an electron beam irradiation step of irradiating the ink applied on the substrate with an electron beam; including. Since the ink of the present disclosure is used in the image recording method of the present disclosure, effects similar to those of the ink of the present disclosure (that is, an image with excellent image quality can be recorded and migration in the recorded image can be suppressed). effect) is played.
• the ink is applied onto the substrate by an inkjet method.
• the type of substrate is not particularly limited, and examples include paper, plastic-laminated paper (e.g., polyethylene, polypropylene, polystyrene, etc.), metal plate (e.g., metal plate of aluminum, zinc, copper, etc.), and plastic film.
• polyvinyl chloride (PVC) resin cellulose diacetate, cellulose triacetate, cellulose propionate, cellulose butyrate, cellulose acetate butyrate, cellulose nitrate, polyethylene terephthalate (PET), polyethylene (PE) ), polystyrene (PS: Polystyrene), polypropylene (PP: Polypropylene), polycarbonate (PC: Polycarbonate), polyvinyl acetal, films such as acrylic resin), paper laminated or vapor-deposited with the above-mentioned metal, and the above-mentioned metal is laminated or vapor-deposited with a plastic film.
• PVC polyvinyl chloride
• the method of applying ink by an inkjet method is not particularly limited as long as it is a method capable of recording an image, and a known method can be used.
• Inkjet recording methods include, for example, a charge control method that uses electrostatic attraction to eject ink, a drop-on-demand method (pressure pulse method) that uses vibration pressure of a piezo element, and an ink that converts an electrical signal into an acoustic beam.
• Acoustic inkjet method in which ink is ejected using radiation pressure by irradiating to the surface
• thermal inkjet bubble jet (registered trademark)) method in which ink is heated to form bubbles and the resulting pressure is used. .
• the inkjet head used in the inkjet recording method a short serial head is used, and the shuttle method performs recording while scanning the head in the width direction of the substrate, and the recording elements are arranged corresponding to the entire side of the substrate. and a line method using a line head that has been developed.
• patterns can be formed on the entire surface of the base material by scanning the base material in a direction that intersects the direction in which the recording elements are arranged, eliminating the need for a transport system such as a carriage for scanning the short head.
• the line method eliminates the need for complicated scanning control of the movement of the carriage and the base material, and only the base material moves.
• the droplet volume of ink ejected from the inkjet head is preferably 1 pL (picoliter) to 100 pL, more preferably 3 pL to 80 pL, and even more preferably 3 pL to 50 pL.
• the ink application process is applying the ink of the present disclosure onto a substrate; irradiating the ink applied on the substrate with ultraviolet rays X containing radiation with a wavelength of 300 nm to 395 nm; is preferably included.
• ultraviolet rays X containing radiation with a wavelength of 300 nm to 395 nm; is preferably included.
• the ink of the present disclosure is not completely cured by UV X irradiation, but is thickened. This provides the effect of pinning exposure.
• the ink applied to the lower layer side is irradiated with ultraviolet X before applying the ink applied to the upper layer side. This suppresses bleeding between the ink on the upper layer side and the ink on the lower layer side.
• the ink irradiated with ultraviolet rays X is irradiated with electron beams for final curing, and a multicolor image with excellent image quality (i.e., line quality) is obtained. .
• Ultraviolet X includes radiation with a wavelength of 300 nm to 395 nm.
• a UV light source used for irradiating the ultraviolet rays X a known UV light source in which at least one of illuminance and irradiation time is variable can be used.
• the UV light source is preferably an LED (Light Emitting Diode) light source.
• the illuminance of irradiation with ultraviolet rays X is preferably 0.10 W/cm 2 to 0.50 W/cm 2 , more preferably 0.20 W/cm 2 to 0.50 W/cm 2 , still more preferably 0.20 W/cm 2 to 0.50 W/cm 2 . 25 W/cm 2 to 0.45 W/cm 2 .
• the irradiation energy of the ultraviolet rays X is preferably 2 mJ/cm 2 to 20 mJ/cm 2 , more preferably 4 mJ/cm 2 to 15 mJ/cm 2 .
• the ink applied onto the base material in the ink applying step is irradiated with an electron beam.
• the electron beam irradiation step by irradiating the ink with an electron beam, the polymerizable compound in the ink is polymerized and the ink is cured, thereby obtaining an image.
• the electron beam irradiation can be performed using an electron beam irradiation apparatus.
• the electron beam irradiation conditions are not particularly limited.
• the acceleration voltage in electron beam irradiation is, for example, 50 kV to 200 kV, preferably 50 kV to 110 kV.
• the dose of electron beam irradiation is, for example, 10 kGy to 100 kGy, preferably 30 kGy to 90 kGy.
• the processing speed in electron beam irradiation is, for example, 1 m/min to 200 m/min.
• the electron beam irradiation may be performed in an environment where the oxygen concentration is 20% by volume or less (more preferably less than 20% by volume, more preferably 5% by volume or less). As a result, inhibition of polymerization by oxygen is suppressed, and migration is further suppressed.
• an inert gas eg, nitrogen gas, argon gas, and helium gas
• an inert gas eg, nitrogen gas, argon gas, and helium gas
• the image recording method of the present disclosure may include other steps than the steps described above, if necessary.
• Recording method A is an image recording method using the first aspect of the ink set of the present disclosure described above.
• Recording method A is an ink application step of sequentially applying the two or more inks in the ink set onto a substrate; an electron beam irradiation step of irradiating the two or more inks applied on the base material with an electron beam; including.
• the effect of the image recording method of the present disclosure can be obtained, and a multicolor image can be recorded using two or more kinds of inks.
• ultraviolet rays X are applied to at least one of the two or more inks applied on the base material in the process of sequentially applying two or more inks on the base material. Irradiation is preferred. According to this aspect, the effect of pinning exposure can be obtained by irradiating ultraviolet rays X, so ink bleeding can be suppressed particularly when two or more types of ink are applied in layers, and as a result, image quality (i.e., line image quality) can be obtained.
• one of two or more inks is applied onto the base material, and an operation of irradiating the applied one with ultraviolet rays X is performed once for the two or more inks. It is more preferable to carry out seed by seed sequentially. According to this aspect, the effect of pinning exposure by irradiation with ultraviolet X can be obtained more effectively. As a result, an image with better image quality (ie, line quality) can be obtained.
• the ink applying step according to this example is a step of using an ink set including white ink, black ink, cyan ink, magenta ink, and yellow ink, and applying these inks onto the substrate in the order described above.
• the ink application process includes: applying white ink, irradiation of ultraviolet rays X to the applied white ink; Applying black ink, UV X irradiation of the applied black ink, application of cyan ink, irradiation of the applied cyan ink with ultraviolet X; application of magenta ink, UV X irradiation of the applied magenta ink; Application of yellow ink, and The applied yellow ink is irradiated with ultraviolet rays X in this order. According to this example, it is possible to more effectively suppress ink bleeding when two or more of these inks are applied in a layered manner, and as a result, an image with better image quality (ie, line quality) can be obtained.
• image quality ie, line quality
• the white ink and the colored ink are applied in this order, and from the dynamic surface tension ⁇ of the white ink 500 ⁇ s after the application of the white ink, the dynamic surface of the colored ink 500 ⁇ s after the application of the colored ink
• the value obtained by subtracting the tension ⁇ (hereinafter also referred to as “dynamic surface tension difference [white ink-colored ink]”) is preferably more than 1 mN/m.
• the insufficient spread of the dots of the colored ink applied on the white ink is suppressed, and as a result, the image quality (that is, the line quality) is improved.
• the colored inks in this aspect may be of only one type, or may be of two or more types. The above effects are particularly effective when each of the white ink and the colored ink contains 1% by mass to 5% by mass of the silicone surfactant with respect to the total amount of the ink.
• the dynamic surface tension 500 ⁇ s (microseconds) after ink application means a value measured by the maximum bubble pressure method under an environment of 23° C. and 55% RH.
• the dynamic surface tension 500 ⁇ s after ink application is measured using, for example, a maximum bubble pressure method dynamic surface tension meter BP100 (manufactured by KRUSS).
• white ink is applied, and then the two or more colored inks are sequentially applied,
• n is an integer of 2 or more
• the absolute value of the value obtained by subtracting the dynamic surface tension ⁇ (n+1) of the n+1-th colored ink applied 500 ⁇ s after the application of the colored ink is preferably 1 mN/m or less.
• both insufficient spread and excessive spread of dots of the n+1th colored ink applied on the nth colored ink are suppressed, and as a result, image quality (that is, line quality) is improved, and color Bleed is suppressed. Furthermore, as a result of suppressing both the insufficient spread and the excessive spread of the (n+1)th colored ink dot, for example, the deformation of an image in which a figure such as a rectangle is drawn is also suppressed.
• the above effects are particularly effective when each of the white ink and the colored ink contains 1% by mass to 5% by mass of the silicone surfactant with respect to the total amount of the ink.
• Recording method B which is a preferred embodiment of the image recording method of the present disclosure, will be described.
• Recording method B is an image recording method using the second aspect of the ink set of the present disclosure described above.
• Recording method B is an ink applying step of applying the ink of the present disclosure and the colored ink described above in the ink set onto a substrate in this order;
• An electron beam irradiation step of irradiating an electron beam to the ink and colored ink of the present disclosure applied on a substrate; is preferably included.
• recording method B is an ink application step of applying the white ink (the ink of the present disclosure containing a white pigment as the pigment (C)) and the colored ink containing a pigment having a hue other than white in the above ink set onto the substrate in this order; , After applying the white ink applied on the substrate, irradiating with ultraviolet rays X containing radiation with a wavelength of 300 nm to 395 nm, further applying the colored ink, and then irradiating with an electron beam; is preferably included.
• Preferred aspects of the ink application step and the electron beam irradiation step in the recording method B are the same as the preferred aspects of the ink application step and the electron beam irradiation step described in the image recording method section.
• Parts means parts by weight.
• composition of Magenta Dispersion D1M ⁇ CINQUASIA MAGENTA RT-355-D (magenta pigment, manufactured by BASF Japan) ... 30 parts SR9003 (polyfunctional polymerizable compound, propoxylated (2) neopentyl glycol diacrylate, manufactured by Sartomer) ... 60 parts SOLSPERSE 32000 (dispersant, manufactured by Noveon) ... 10 copies
• composition of Black Dispersion D1K ⁇ SPECIAL BLACK 250 (black pigment, Orion Engineered Carbons) ... 40 parts SR9003 (polyfunctional polymerizable compound, propoxylated (2) neopentyl glycol diacrylate, manufactured by Sartomer) ... 50 parts SOLSPERSE 32000 (dispersant, manufactured by Noveon) ... 10 copies
• composition of white dispersion D1W ⁇ KRONOS 2300 (white pigment, manufactured by KRONOS) ... 50 parts SR9003 (polyfunctional polymerizable compound, propoxylated (2) neopentyl glycol diacrylate, manufactured by Sartomer) ... 46.5 parts SOLSPERSE 41000 (dispersant, manufactured by Noveon) ... 3.5 copies
• - Viscoat #200 monofunctional polymerizable compound, cyclic trimethylolpropane formal acrylate (CTFA), manufactured by Osaka Organic Chemical Co., Ltd.
• CTFA trimethylolpropane formal acrylate
• 4-HBA monofunctional polymerizable compound, 4-hydroxybutyl acrylate, manufactured by Osaka Organic Chemical Co., Ltd.
• - Speedcure 7010 Hydrogen abstraction type initiator with a molecular weight of 1,899, thioxanthone compound, manufactured by Lambson.
• Omnipol TX Hydrogen abstraction type initiator with a molecular weight of 790, thioxanthone compound, IGM Resins B.I. V. Company made.
• Omnipol BP Hydrogen abstraction type initiator with a molecular weight of 790, thioxanthone compound, IGM Resins B.I. V. Company made.
• Omnipol BP Hydrogen abstraction type initiator with a molecular weight of 790, thioxan
• Omnipol TP a non-hydrogen abstraction type initiator (acylphosphine oxide initiator) with a molecular weight of 1035, a comparative initiator, IGM Resins B.V. V. Company made.
• ITX a hydrogen abstraction type initiator (isopropylthioxanthone) with a molecular weight of 254, a comparative initiator.
• ⁇ UV-22 polymerization inhibitor, Irgastab (registered trademark) UV-22, Poly[oxy(methyl-1,2-ethanediyl)],.alpha.,.alpha.',.alpha.''-1,2 ,3-propanetriyltris[.omega.-[(1-oxo-2-propen-1-yl)oxy]-,2,6-bis(1,1-dimethylethyl)-4-(phenylenemethylene)cyclohexa-2,5 -dien-1-one, manufactured by BASF. ⁇ BYK-378 ... Silicone surfactant (polyether-modified polydimethylsiloxane), manufactured by BYK Chemie. ⁇ BYK-3760 ... Silicone surfactant, manufactured by BYK Chemie. ⁇ BYK-350 ... Acrylic surfactant, manufactured by BYK Chemie.
• Example C1 (using ink C1)] ⁇ Recording a solid image>
• a single-pass inkjet head (specifically, a Samba head manufactured by Fujifilm Dymatex Co., Ltd., 1200 npi, minimum liquid amount 2 pL; Also simply referred to as “heads”) were arranged, and an LED light source (385 nm) for pinning exposure was arranged between each head and downstream of the most downstream head.
• Ink W1, ink C1, ink M1, ink Y1, and ink K1 were introduced into each head in this order from the upstream side.
• a base material (specifically, Taiko PET manufactured by Futamura Chemical Co., Ltd., thickness 50 ⁇ m) which had been subjected to corona treatment immediately before image recording was set on the conveying table.
• the substrate is transported at a transport speed of 50 m/min, and the ink C1 is applied from the head to the substrate being transported in the form of a solid image.
• UV (ultraviolet) irradiation was applied by a positioned LED light source.
• the conditions for the pinning exposure were UV irradiation for 0.024 seconds at an illuminance of 0.40 W/cm 2 .
• image quality For the line image, using a dot analyzer (manufactured by Oji Scientific Instruments Co., Ltd.; DA6000), the raggedness (that is, the deviation of the line image edge obtained from the ideal edge obtained by the least squares method) is measured. Based on the measurement result, Image quality was evaluated according to the following evaluation criteria. In the following evaluation criteria, A is the most excellent rank for image quality.
• Raggedness of the line image is less than 4.0.
• B The line image has a raggedness of 4.0 or more and less than 5.0.
• C Raggedness of the line image is 5.0 or more and less than 6.0.
• D Raggedness of the line image is 6.0 or more and less than 7.0.
• E Raggedness of the line image is 7.0 or more.
• A The amount of migration is 0 ppb.
• B The amount of migration is more than 0 ppb and 10 ppb or less.
• C The amount of migration is more than 10 ppb and 1 ppm or less.
• D The amount of migration is more than 1 ppm and 10 ppm or less.
• E The amount of migration is over 10 ppm.
• Adhesion- A The ratio (%) of peeling of the lattice was 0%.
• B The ratio (%) of peeling of the lattice was more than 0% and 5% or less.
• C The ratio (%) of peeling of the lattice was over 5%.
• Example C2B The same operation as in Experimental Example C2 was performed except that the pinning exposure was not performed and the EB irradiation as the final curing was changed to the UV irradiation as the final curing.
• an LED light source (385 nm) was used, and UV was irradiated for 0.024 seconds at an illuminance of 5.0 W/cm 2 . Table 1 shows the results.
• the polymerization initiator (A) contains a hydrogen abstraction type polymerization initiator having a molecular weight of 500 or more,
• a hydrogen abstraction type polymerization initiator having a molecular weight of 500 or more
• Experimental example C2B comparative example in which ink C2 was used as UV curing ink instead of electron beam curing ink was compared with experimental example C2A (example) in which ink C2 was used as electron beam curing ink.
• image quality, migration, and adhesion decreased.
• the ink of the present disclosure (for example, the ink of each example) having a relatively small amount of polymerization initiator of 2% by mass or less may be insufficient in curability against irradiation with ultraviolet rays, but electron beam irradiation may be insufficient. It was confirmed that the ink has sufficient curability against irradiation, that is, it is effective as an electron beam curing ink.
• Example 101 ⁇ Recording a solid image> A single pass ink jet recording apparatus similar to the apparatus used in Example C1 was prepared. Ink W3, ink C2, ink M2, ink Y2, and ink K2 were introduced into each head in this order from the upstream side. A base material (specifically, Taiko PET manufactured by Futamura Chemical Co., Ltd., thickness 50 ⁇ m) which had been subjected to corona treatment immediately before image recording was set on the conveying table.
• a base material specifically, Taiko PET manufactured by Futamura Chemical Co., Ltd., thickness 50 ⁇ m
• the substrate is transported at a transport speed of 50 m / min, and the substrate being transported is application of ink W3, pinning exposure to the applied ink W3; application of ink C2, Pinning exposure to applied ink C2, Application of ink M2, pinning exposure to the applied ink M2; application of ink Y2; pinning exposure to the applied ink Y2; application of ink K2, pinning exposure to the applied ink K2, and EB irradiation as final curing was applied in this order. This gave a multicolor solid image.
• the multicolor solid image A is an image in which 1 cm ⁇ 10 cm rectangular images of cyan, magenta, yellow, and black are arranged adjacently on a white image with a halftone dot rate of 100%.
• the multicolor solid image B is a 5 cm ⁇ 15 cm rectangular 4 CSorid image (each color has a dot rate of 50%) in which cyan, magenta, yellow, and black are superimposed on a white image with a dot rate of 100%. is an image placed in which 1 cm ⁇ 10 cm rectangular images of cyan, magenta, yellow, and black are arranged adjacently on a white image with a halftone dot rate of 100%.
• the multicolor solid image B is a 5 cm ⁇ 15 cm rectangular 4 CSorid image (each color has a dot rate of 50%) in which cyan, magenta, yellow, and black are superimposed on a white image with a dot rate of 100%. is an image placed in
• ⁇ Recording line images> By changing the ink application area, a multicolor image was recorded in which 1 pt line images of each color of cyan, magenta, yellow, and black were arranged on a white solid image with a halftone dot rate of 100%. A multicolor line image was recorded in the same manner as for recording a multicolor solid image, except for the above.
• Example C1 ⁇ Evaluation> Regarding the multinary color images (multinary color solid image A, multinary color solid image B, and multinary color line image), the same evaluations (image quality, amount of migration, and adhesion) in Example C1 were made. carried out.
• the multinary color line image was used for the image quality evaluation
• the multinary color solid image B was used for the migration amount evaluation
• the multinary color solid image B was used for the adhesion evaluation.
• Table 6 shows the results.
• dynamic surface tension means the dynamic surface tension ⁇ of the ink 500 ⁇ s after the application of the ink.
• a multicolor image for image deformation evaluation was obtained as follows. A black solid image with black ink having three 1 cm square openings was superimposed on the white solid image. The underlying white solid image was exposed from three openings in the black solid image. A 1 cm square cyan solid image, a 1 cm square magenta solid image, and a 1 cm solid image were applied to each of the three openings so as to overlap (i.e., obscure the white solid image exposed from the openings). A yellow solid image of each corner square was recorded. As described above, a multicolor image for image deformation evaluation was obtained. The multicolor image for image deformation evaluation was visually observed to confirm the presence or absence of deformation of each square solid image, and the image deformation was evaluated according to the following evaluation criteria.
• Example 106 The same operation as in Experimental Example 101 was performed except that the combination of inks was changed as shown in Table 6 and pinning exposure was performed only for W3 among the applied inks.

Landscapes

• Chemical & Material Sciences (AREA)
• Life Sciences & Earth Sciences (AREA)
• Engineering & Computer Science (AREA)
• Materials Engineering (AREA)
• Wood Science & Technology (AREA)
• Organic Chemistry (AREA)
• Physics & Mathematics (AREA)
• Health & Medical Sciences (AREA)
• Electromagnetism (AREA)
• General Health & Medical Sciences (AREA)
• Toxicology (AREA)
• Inks, Pencil-Leads, Or Crayons (AREA)
• Ink Jet Recording Methods And Recording Media Thereof (AREA)

Priority Applications (4)

Applications Claiming Priority (4)

Related Child Applications (1)

Publications (1)

Family

ID=83458848

Family Applications (1)

Country Status (4)

Cited By (1)

Citations (10)

Family Cites Families (5)

• 2022
  • 2022-03-08 JP JP2023510757A patent/JPWO2022209635A1/ja active Pending
  • 2022-03-08 EP EP22779859.2A patent/EP4316850B1/en active Active
  • 2022-03-08 WO PCT/JP2022/010046 patent/WO2022209635A1/ja not_active Ceased
• 2023
  • 2023-09-27 US US18/475,218 patent/US20240018374A1/en active Pending

Patent Citations (11)

Non-Patent Citations (2)

Also Published As

Similar Documents

Legal Events