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WO2018180693A1 - Composition d'encre aqueuse pour enregistrement à jet d'encre, et procédé de formation d'image - Google Patents

Composition d'encre aqueuse pour enregistrement à jet d'encre, et procédé de formation d'image Download PDF

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Publication number
WO2018180693A1
WO2018180693A1 PCT/JP2018/010773 JP2018010773W WO2018180693A1 WO 2018180693 A1 WO2018180693 A1 WO 2018180693A1 JP 2018010773 W JP2018010773 W JP 2018010773W WO 2018180693 A1 WO2018180693 A1 WO 2018180693A1
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WO
WIPO (PCT)
Prior art keywords
resin fine
fine particles
water
ink composition
structural unit
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Ceased
Application number
PCT/JP2018/010773
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English (en)
Japanese (ja)
Inventor
裕久 外園
史子 玉國
紘平 竹下
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Fujifilm Corp
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Fujifilm Corp
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Filing date
Publication date
Application filed by Fujifilm Corp filed Critical Fujifilm Corp
Priority to JP2019509342A priority Critical patent/JP6621566B2/ja
Publication of WO2018180693A1 publication Critical patent/WO2018180693A1/fr
Anticipated expiration legal-status Critical
Ceased legal-status Critical Current

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Classifications

    • 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
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B41—PRINTING; LINING MACHINES; TYPEWRITERS; STAMPS
    • B41M—PRINTING, DUPLICATING, MARKING, OR COPYING PROCESSES; COLOUR PRINTING
    • B41M5/00—Duplicating or marking methods; Sheet materials for use therein
    • 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

Definitions

  • the present invention relates to a water-based ink composition for inkjet recording and an image forming method.
  • an image recording method for forming an image on a recording medium such as paper based on an image data signal there are recording methods such as an electrophotographic method, a sublimation type and a melt type thermal transfer method, and an ink jet method.
  • the ink jet recording method does not require a printing plate and forms an image directly on a recording medium by ejecting ink only to the image forming unit. Therefore, the ink can be used efficiently, and the running cost is reduced. Further, the ink jet recording method has a printing apparatus with a relatively low cost compared to a conventional printing machine, can be downsized, and has less noise. Thus, the ink jet recording method has various advantages over other image recording methods.
  • Patent Document 1 discloses a pigment, water, a water-soluble organic solvent, and a copolymer of a monomer (A) having a carboxy group or a salt thereof and an aliphatic monomer. Inkjet inks containing are described.
  • Patent Document 2 describes an ink for ink jet recording containing water, a pigment, and one specific copolymer.
  • Patent Document 3 describes an ink-jet ink containing a pigment, water, a water-soluble organic solvent, and a copolymer of 12-methacrylamide decanoic acid and an aromatic monomer.
  • the ink used in the ink jet recording method is required to be capable of forming an image exhibiting mechanical strength (abrasion resistance) that is not damaged or peeled off when an external force is applied.
  • the ink used in the ink jet recording method also has a performance (blocking resistance) that prevents color transfer between the front and back of the stacked recording media or adhesion between the recording media when the recording media on which the images are formed are stacked. It is required to be able to form an image with
  • the ink is also required to have ejection stability capable of stably ejecting a desired amount of ink from the nozzle in order to stably form a target image with high accuracy.
  • the ink jet recording method has been mainly used in the fields of office printers, home printers, and the like, but in recent years, its use has been expanded to the commercial printing field, and the speed of ink jet recording has been increased. Accordingly, the demand for ink ejection stability is becoming more sophisticated year by year.
  • the ink jet recording method has a peculiar and urgent problem that if the nozzle is left after image formation, for example, once the image formation is paused (interrupted), the nozzle is clogged. For this reason, the ink used in the ink jet recording method is strongly required to have a characteristic of being normally ejected even after a pause (also referred to as latency or neglectability).
  • the present invention relates to a water-based ink composition for ink-jet recording capable of forming an image having excellent latency when applied to an ink-jet recording method and excellent in abrasion resistance and blocking resistance, and the water-based ink composition for ink-jet recording. It is an object of the present invention to provide an image forming method.
  • an aqueous ink composition containing at least two kinds of resin fine particles obtained by combining resin fine particles having a glass transition temperature having a specific temperature difference from the glass transition temperature of the resin fine particles in an aqueous medium is an ink jet recording. It has been found that it has excellent latency when used as an ink, and also has excellent scratch resistance and blocking resistance of an image formed using this aqueous ink composition.
  • the present invention has been further studied based on these findings and has been completed.
  • An aqueous ink composition for ink-jet recording comprising an aqueous medium and at least two kinds of resin fine particles, resin fine particles A and resin fine particles B,
  • the polymer forming the resin fine particles A contains 1 to 20% by mass of the structural unit represented by the following general formula (1) in the polymer forming the resin fine particles A.
  • R 1 represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms
  • X 1 represents a divalent linking group
  • Y 1 represents an anionic group.
  • the structural unit represented by the general formula (1) is a structural unit represented by the following general formula (2) or the following general formula (3).
  • R 1 and Y 1 have the same meanings as R 1 and Y 1 in the general formula (1).
  • a 1 represents —O— or —N (R 3 ) —, and R 3 represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.
  • L 1 represents a divalent linking group having 6 to 30 carbon atoms.
  • L 2 represents a single bond, —C ( ⁇ O) O— or —C ( ⁇ O) N (R 4 ) —, and R 4 represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.
  • the number of bonds of atoms constituting the longest chain is 9 to 60, respectively.
  • Y 1 is —C ( ⁇ O) OM, —S ( ⁇ O) 2 OM or —OP ( ⁇ O) (OM) 2
  • M is a hydrogen atom, an alkali metal ion or an ammonium ion.
  • ⁇ 1> or ⁇ 2> The water-based ink composition for ink jet recording according to ⁇ 2>.
  • ⁇ 4> The aqueous ink for inkjet recording according to any one of ⁇ 1> to ⁇ 3>, wherein Y 1 is —C ( ⁇ O) OM, and M is a hydrogen atom, an alkali metal ion, or an ammonium ion.
  • ⁇ 5> The ink jet recording according to any one of ⁇ 1> to ⁇ 4>, wherein the polymer forming the resin fine particles A has a structural unit derived from an ethylenically unsaturated compound having an aromatic ring or an aliphatic ring.
  • ⁇ 8> The water-based ink for ink-jet recording according to any one of ⁇ 1> to ⁇ 7>, wherein the content of the resin fine particles is 1 to 15% by mass with respect to the total mass of the water-based ink composition for ink-jet recording.
  • Composition. ⁇ 9> The water-based ink composition for ink-jet recording according to any one of ⁇ 1> to ⁇ 8>, containing a pigment.
  • An image forming method including an ink applying step of forming an image by applying the aqueous ink composition for ink jet recording according to ⁇ 9> above onto a recording medium by an ink jet method.
  • ⁇ 11> The image forming method according to ⁇ 10>, wherein the water-based ink composition for inkjet recording is directly applied onto a low water-absorbing recording medium or a non-water-absorbing recording medium.
  • substituents when there are a plurality of substituents, linking groups, ligands, structural units, etc. (hereinafter referred to as substituents) represented by specific symbols, or a plurality of substituents, etc. are defined simultaneously or alternatively, the respective substituents and the like may be the same as or different from each other. The same applies to the definition of the number of substituents and the like.
  • group of each group described as an example of each substituent is used to include both an unsubstituted form and a form having a substituent.
  • alkyl group means an alkyl group which may have a substituent.
  • (meth) acrylate is used to mean to include both acrylate and methacrylate.
  • (meth) acrylic acid means a range including numerical values described before and after “to” as a lower limit value and an upper limit value.
  • the aqueous ink composition for ink jet recording of the present invention can form an image having excellent latency when applied to an ink jet recording method and excellent in abrasion resistance and blocking resistance.
  • the image forming method of the present invention can stably (without clogging) forming an image excellent in abrasion resistance and blocking resistance.
  • water-based ink composition for ink-jet recording of the present invention Preferred embodiments of the water-based ink composition for ink-jet recording of the present invention (hereinafter sometimes simply referred to as the water-based ink composition of the present invention) and the image forming method are described below.
  • the water-based ink composition of the present invention includes an aqueous medium, resin fine particles A made of a polymer having a specific structure, and at least two resin fine particles of resin fine particles B having a glass transition temperature having a specific temperature difference with respect to the resin fine particles A. Containing.
  • the aqueous ink composition of the present invention usually contains a pigment. When the aqueous ink composition of the present invention does not contain a pigment, it can be used as a clear ink, and when it contains a pigment, it can be used for color image formation.
  • the aqueous medium used in the present invention contains at least water and, if necessary, contains at least one water-soluble organic solvent.
  • - water As water used for this invention, it is preferable to use the water which does not contain ionic impurities, such as ion-exchange water and distilled water.
  • the water content in the water-based ink composition is appropriately selected depending on the purpose, but is usually preferably 10 to 95% by mass, more preferably 30 to 80% by mass, and more preferably 50 to 50% by mass. More preferably, it is 70 mass%.
  • the aqueous medium in the present invention preferably contains at least one water-soluble organic solvent.
  • the water-soluble organic solvent By containing the water-soluble organic solvent, it is possible to obtain the effect of preventing drying, wetting or promoting penetration.
  • prevention of drying means preventing ink from adhering to and drying from the ink discharge port of the ejection nozzle to form an aggregate.
  • a water-soluble organic solvent having a vapor pressure lower than that of water is preferred.
  • the water-soluble organic solvent can be used as a penetration accelerator that enhances ink permeability to paper.
  • water-soluble organic solvent examples include alkyl alcohols having 1 to 4 carbon atoms, alkanediols (polyhydric alcohols), sugar alcohols, glycol ethers and the like.
  • alkyl alcohol having 1 to 4 carbon atoms include, but are not limited to, ethanol, methanol, butanol, propanol, isopropanol and the like.
  • the alkanediol is not particularly limited, but glycerin, 1,2,6-hexanetriol, trimethylolpropane, ethylene glycol, propylene glycol, dipropylene glycol, 1,2-butanediol, 1,2-hexanediol, 1 , 2-heptanediol, 1,2-octanediol, 1,2-nonanediol, 1,2-decanediol, and those described later.
  • glycol ether Although it does not specifically limit as glycol ether, The following each compound is mentioned. Ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monopropyl ether, ethylene glycol monobutyl ether, ethylene glycol monopentyl ether, ethylene glycol monohexyl ether, ethylene glycol monoheptyl ether, ethylene glycol monooctyl ether, ethylene glycol monononyl Ether, ethylene glycol mono-2-ethylhexyl ether, ethylene glycol monomethyl ether acetate, Diethylene glycol monomethyl ether, diethylene glycol monoethyl ether, diethylene glycol monopropyl ether, diethylene glycol monobutyl ether, diethylene glycol monopentyl ether, diethylene glycol monohexyl ether, diethylene glycol monoheptyl ether, diethylene glycol monooctyl ether, diethylene glyco
  • a water-soluble organic solvent can be used individually by 1 type or in combination of 2 or more types.
  • polyhydric alcohols are useful.
  • polyol compounds are preferred, and aliphatic diols are preferred.
  • aliphatic diols include 2-ethyl-2-methyl-1,3-propanediol, 3,3-dimethyl-1,2-butanediol, 2,2-diethyl-1,3-propanediol, -Ethyl-1,3-hexanediol, 2,2,4-trimethyl-1,3-pentanediol and the like.
  • preferred examples include 2-ethyl-1,3-hexanediol and 2,2,4-trimethyl-1,3-pentanediol.
  • the water-soluble organic solvent in the present invention may contain at least one compound represented by the following structural formula (S) from the viewpoint of curling generation in the recording medium.
  • AO represents at least one of an ethyleneoxy group (EO) and a propyleneoxy group (PO), and among them, a propyleneoxy group is preferable.
  • Each AO in the above (AO) t , (AO) u , and (AO) v may be the same or different.
  • EO and PO are bonded with their ethylene group or propylene group positioned on the hydroxyl group side.
  • the water-soluble organic solvent may be used alone or in combination of two or more.
  • the content of the water-soluble organic solvent in the aqueous ink composition is preferably 1% by mass or more and 60% by mass or less, more preferably 5% by mass or more and 40% by mass or less, and further preferably 7% by mass or more and 30% by mass or less. It is below mass%.
  • the aqueous ink composition of the present invention contains at least two types of resin fine particles, resin fine particles A and resin fine particles B (hereinafter also simply referred to as “resin fine particles used in the present invention”).
  • the resin fine particles A and the resin fine particles B are both composed of a polymer, and the polymer forming the resin fine particles A (hereinafter also simply referred to as “polymer A”) is a structural unit (I) represented by the following general formula (1). ) In the polymer A, and the absolute value of the glass transition temperature difference between the resin fine particles A and the resin fine particles B is 30 to 100 ° C.
  • the water-based ink composition of the present invention contains the resin fine particles used in the present invention
  • an image having excellent latency when applied to an ink jet recording method and excellent in abrasion resistance and blocking resistance is formed. Can do.
  • the structural unit (I) of the polymer A has an anionic group Y 1
  • the polymer A containing the structural unit (I) functions as a so-called surfactant. Therefore, the stability of the resin fine particles used in the present invention is improved, and gelation of the aqueous ink composition (solvent volatilization of the aqueous ink composition) can be suppressed.
  • the resin fine particles used in the present invention include, in addition to the resin fine particles A, the resin fine particles B having a glass transition temperature having a specific temperature difference with respect to the glass transition temperature of the resin fine particles A, whereby the aqueous ink composition of the present invention.
  • the resin fine particles A and the resin fine particles B have different functions and can improve both abrasion resistance and blocking.
  • the resin fine particles used in the present invention are thought to be able to exhibit and maintain a good balance between the heat-sealing force due to the resin fine particles having a low glass transition temperature and the thermal stability due to the resin fine particles having a high glass transition temperature. Therefore, the resin fine particles used in the present invention can improve the scratch resistance and blocking resistance of images.
  • the resin fine particles A and the resin fine particles B may be one kind or two kinds or more, respectively. Further, the resin fine particles used in the present invention may have resin fine particles different from the resin fine particles A and the resin fine particles B as long as the effects of the present invention are not impaired. In these cases, the resin fine particles used in the present invention may contain at least one kind of resin fine particles A and at least one kind of resin fine particles B.
  • the aqueous ink composition of the present invention contains a plurality of resin fine particles A, it is not necessary for all of the resin fine particles A to satisfy the glass transition temperature difference in the above range with respect to the resin fine particles B, and at least one of the resin fine particles B In contrast, the glass transition temperature difference in the above range may be satisfied.
  • the aqueous ink composition of the present invention preferably contains a total of 1 to 15% by mass of resin fine particles (that is, resin fine particles containing at least two kinds of resin fine particles A and resin fine particles B) used in the present invention.
  • the content is more preferably 1 to 10% by mass, and further preferably 4 to 10% by mass.
  • the aqueous ink composition of the present invention contains the resin fine particles used in the present invention in a total amount of 1 to 15% by mass, whereby the ejection stability and latency of the aqueous ink composition are improved.
  • R 1 represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.
  • R 1 is preferably a hydrogen atom or methyl, more preferably methyl.
  • X 1 represents a divalent linking group.
  • X 1 is not particularly limited as long as it satisfies the number of bonds of atoms constituting the longest chain, which will be described later.
  • the linking group include a linear, branched or cyclic alkylene group, an arylene group, —O—, —NR 3 —, —S— or —C ( ⁇ O) —, and the atoms constituting the longest chain
  • a divalent linking group formed by linking these alone or two or more thereof is selected.
  • the number of the groups or atoms to be linked can be, for example, 42 or less.
  • R 3 is as described later.
  • Y 1 represents an anionic group.
  • an anionic group refers to a group capable of forming an anion in an aqueous ink composition.
  • Y 1 is compatible with latency, image scratch resistance and blocking resistance at a high level.
  • Y 1 is —C ( ⁇ O) OM, —S ( ⁇ O) 2 OM, —OS ( ⁇ O) 2 OM.
  • M represents a hydrogen atom, an alkali metal ion or an ammonium ion.
  • M is preferably an alkali metal ion, more preferably a sodium ion or a potassium ion, and still more preferably a potassium ion, from the viewpoint of ejection stability, latency, and resin fine particle stability.
  • M may be dissociated (free).
  • the longest number of atoms is 9 to 60.
  • the maximum number of atoms in —X 1 —Y 1 is preferably 9 to 50, more preferably 9 to 40, still more preferably 10 to 23, and particularly preferably 12 to 20 in terms of latency.
  • the longest number of atoms is the atom located at the farthest end among the groups represented by —X 1 —Y 1 , starting from the carbon atom to which R 1 in general formula (1) is bonded (zero).
  • the longest bond of atoms up to is the longest chain
  • the longest chain is a bond of up to one and the farthest end potassium atom, and the maximum number of atoms at this time is 16.
  • the atom at the farthest end is not particularly limited, but is preferably M in Y 1 .
  • -Structural unit represented by general formula (2) or general formula (3)- The structural unit represented by the general formula (1) is preferably a structural unit represented by the general formula (2) or the general formula (3), and has a high level of latency, abrasion resistance and blocking resistance.
  • the structural unit represented by the general formula (2) is more preferable.
  • R 1 and Y 1 have the same meanings as R 1 and Y 1 in the general formula (1).
  • a 1 represents —O— or —NR 3 —.
  • R 3 is a hydrogen atom or an alkyl group having 1 to 4 carbon atoms.
  • a 1 is preferably —NR 3 —, more preferably —NH—.
  • L 1 represents a divalent linking group having 6 to 30 carbon atoms.
  • an alkylene group or a group containing an alkyleneoxy group formed by linking —O— and an alkylene group is preferable, and an alkylene group is more preferable.
  • the number of the groups or atoms to be linked can be, for example, 40 or less.
  • the alkylene group and the alkylene moiety in the alkyleneoxy group may be linear or branched, but are preferably linear from the viewpoints of ejection stability, latency, and resin fine particle stability.
  • the alkylene group preferably has 8 to 22 carbon atoms, more preferably 8 to 18 carbon atoms, still more preferably 8 to 16 carbon atoms, still more preferably 8 to 14 carbon atoms, particularly preferably 10 to 12 carbon atoms, and most preferably. It has 11 carbon atoms.
  • the carbon number of the alkylene moiety in the alkyleneoxy group is the same as the preferable carbon number of the alkyl group except that the upper limit is 30 (lower limit value).
  • R 1, A 1, L 1 and Y 1, respectively, the general formula (2) have the same meanings as R 1, A 1, L 1 and Y 1 of a preferred form also the same .
  • L 2 represents a single bond, —C ( ⁇ O) O— or —C ( ⁇ O) N (R 4 ) —.
  • L 2 is preferably a single bond.
  • R 4 represents a hydrogen atom or an alkyl group having 1 to 4 carbon atoms, preferably a hydrogen atom.
  • the longest number of atoms is 9 to 60, and the preferred range is the longest number of atoms in the group represented by -X 1 -Y 1 in the general formula (1). Is the same range.
  • the total content of the structural unit (I) represented above is a resin, if desired, from the viewpoint that both latency (ejection stability) and image abrasion resistance and blocking resistance can be achieved at a high level. From the viewpoint of the stability of the fine particles, it is 1 to 20% by mass, preferably 2 to 10% by mass.
  • the total content is the content of the structural unit of the general formula (3) when the polymer A does not have the structural unit of the general formula (2), and the polymer A has the structural unit of the general formula (3). If not, it is the content of the structural unit of the general formula (2), and when the polymer A contains both the structural unit of the general formula (2) and the structural unit of the general formula (3), It is the total content.
  • a preferred specific example of the structural unit shown below shows a structure in which M in the above general formulas (1) to (3) is a hydrogen atom. Instead of this hydrogen atom, an alkali metal ion or an ammonium ion is used.
  • the adopted form is also preferable as the structural unit (I).
  • Et represents ethyl
  • Pr represents propyl
  • Bt represents butyl. * Indicates a linking site.
  • the polymer A has a structural unit (II) other than the structural unit (I) (referred to as “other structural unit (II)”) (II).
  • Other structural units (II) are not particularly limited, and preferable examples include the structural units described in JP-A Nos. 2001-181549 and 2002-88294.
  • the content of the other structural unit (II) of the polymer A is appropriately determined in consideration of the type and content of the structural unit (I), the glass transition temperature of each resin fine particle, the difference thereof, and the like. . As content of other structural unit (II), it can set to the range mentioned later, for example.
  • the polymer A preferably contains the structural unit (i) of an ethylenically unsaturated compound having an aromatic ring or an aliphatic ring as the other structural unit (II).
  • the aromatic ring or aliphatic ring contained in the structural unit (i) include a benzene ring, a naphthalene ring, an anthracene ring, and an aliphatic hydrocarbon ring having 5 to 20 carbon atoms. An aliphatic hydrocarbon ring of several 6 to 10 is preferable.
  • These aromatic rings or aliphatic rings may have a substituent.
  • the aromatic ring or the aliphatic ring has a substituent, the substituent is not particularly limited, and examples thereof include substituents other than Y 1 .
  • an ethylenically unsaturated compound having an aromatic ring or aliphatic ring leading to the structural unit (i) is preferable, and styrene or (meth) acrylate A compound or a (meth) acrylamide compound is more preferable, and an optionally substituted styrene or (meth) acrylate compound is more preferable.
  • the ethylenically unsaturated compound is not particularly limited, but is a compound that leads to a structural unit represented by the following general formulas (A) to (E), more specifically, styrene, benzyl (meth) acrylate, Examples include isobornyl (meth) acrylate, cyclohexyl (meth) acrylate, and dicyclopentanyl (meth) acrylate.
  • the structural unit (i) preferably contains a structural unit represented by any one of the following general formulas (A) to (E) from the viewpoint of the abrasion resistance of the obtained image. It is more preferable that the structural unit represented by the following general formula (A) is included from a viewpoint of discharge property.
  • R 11 and R 12 each independently represents a methyl group or a hydrogen atom.
  • R 13 each independently represents a linear or branched alkyl group having 1 to 10 carbon atoms.
  • N in the general formulas (A) and (B) represents an integer of 0 to 5.
  • N in the general formula (C) is an integer of 0 to 11.
  • L 11 is a single bond, a linear, branched or cyclic alkylene group having 1 to 18 carbon atoms, an arylene group having 6 to 18 carbon atoms, —O—, —NH—, —S— or —C ( ⁇ O) — or a divalent linking group formed by linking two or more of these.
  • R 11 is preferably a hydrogen atom.
  • R 12 is preferably a methyl group.
  • each R 13 is independently preferably a linear or branched alkyl group having 1 to 4 carbon atoms, more preferably a methyl group or an ethyl group.
  • n is preferably an integer of 0 to 2, more preferably 0 or 1, and still more preferably 0.
  • L 11 is preferably a divalent linking group containing —O— or —NH— at the bonding site with the carbonyl carbon atom described in the general formula (B). And a divalent linking group containing a linear, branched or cyclic alkylene group having 1 to 18 carbon atoms and containing —O— or —NH— at the bonding site is more preferred. —OCH 2 — Or, —NHCH 2 — is more preferred, and —OCH 2 — is particularly preferred.
  • L 11 contains —O— or —NH— at the bonding site with the carbonyl carbon atom described in the general formulas (C) to (E). A divalent linking group is preferred, —O— or —NH— is more preferred, and —O— is still more preferred.
  • the structural unit represented by the general formula (A) is preferably a structural unit derived from styrene.
  • the structural unit represented by the general formula (B) is preferably a structural unit derived from benzyl (meth) acrylate.
  • the structural unit represented by the general formula (C) is preferably a structural unit derived from cyclohexyl (meth) acrylate.
  • the structural unit represented by the general formula (D) is preferably a structural unit derived from isobornyl (meth) acrylate.
  • the structural unit represented by the general formula (E) is preferably a structural unit derived from dicyclopentanyl (meth) acrylate.
  • Polymer A may have one or more structural units (i).
  • the total content of the structural unit (i) is preferably 1 to 80% by mass, and preferably 5 to 75% by mass in consideration of the manufacturing suitability (filterability) of the resin fine particles in addition to the scratch resistance. More preferred is 10 to 70% by mass.
  • the total content is the content of one kind of structural unit when one kind of structural unit (i) is contained in the polymer A, and when two or more kinds are contained, It means the total content of structural units.
  • particularly preferred structural units derived from styrene are contained in the polymer A in view of ejection stability and scratch resistance, and if desired, from the viewpoint of production suitability (filterability) of resin fine particles.
  • the amount is preferably 3 to 50% by mass, more preferably 5 to 40% by mass, and still more preferably 10 to 35% by mass.
  • the polymer A may have a structural unit (ii) other than the structural unit (i) as the other structural unit (II).
  • the structural unit (ii) is not particularly limited as long as it is derived from a compound polymerizable with the above structural unit, and is preferably a structural unit derived from a (meth) acrylamide compound or a (meth) acrylate compound, More preferably, the structural unit is derived from an acrylate compound.
  • the structural unit (ii) is preferably an alkyl (meth) acrylate compound in which the alkyl group has 1 to 10 carbon atoms.
  • the alkyl group may be linear or branched and may have a cyclic structure (excluding those included in the above general formula (C) to general formula (E)).
  • the structural unit (ii) may have a substituent.
  • the substituent that the structural unit (ii) may have is not particularly limited, and examples thereof include substituents other than the above Y 1 , such as a hydroxyl group and an amino group.
  • the polymer A may have one or more structural units (ii).
  • the total content of the structural unit (ii) is preferably 0 to 90% by mass, more preferably 0 to 70% by mass, from the viewpoint of ejection stability and abrasion resistance. .
  • the total content is the content of one type of structural unit when one type of structural unit (ii) is contained in each polymer. When two or more types of structural units are contained, the two or more types of structures are contained. It means the total content of units.
  • Polymer A may have a structural unit other than the above structural unit as the other structural unit (II).
  • a structural unit is not particularly limited, and examples thereof include a structural unit derived from (meth) acrylic acid or a salt thereof (including the above alkali metal salt or ammonium salt).
  • the total content of the structural unit in each polymer is preferably 0 to 20% by mass, more preferably 0 to 15% by mass, and still more preferably 0 to 10% by mass.
  • the structure (structural unit) is not particularly limited. Preferably, it has at least one selected from the structural units (I) and (II). That is, the polymer B may have the structural units (I) and (II), may not have the structural unit (I), and may have the structural unit (II). More preferably, the polymer B has the structural unit (I).
  • the structural unit (I) is as described above.
  • the type or content of the structural unit forming the polymer B is appropriately determined in consideration of the glass transition temperature of the resin fine particles B, the difference (absolute value) between the glass transition temperatures of the resin fine particles A and B, and the like.
  • content of structural unit (I) it can set to the following range, for example.
  • the total content of the structural unit (I) in the polymer B is further improved from the viewpoint of achieving a higher level of both latency, image abrasion resistance and blocking resistance. From the viewpoint of further improving the stability of the resin fine particles as desired, it is preferably 0.5 to 30% by mass, more preferably 1 to 20% by mass, and still more preferably 2 to 10% by mass.
  • the polymer B has another structural unit (II), which is also a preferred embodiment.
  • the structural unit which comprises this polymer B is although it does not specifically limit, It is preferable to have the said structural unit (II).
  • the structural unit (II) is as described above.
  • the content of the structural unit (II) in the polymer B is also the same as the content in the polymer A.
  • the content of the structural unit (II) is preferably 20 to 100% by mass in the polymer B.
  • the glass transition temperature of the resin fine particles used in the present invention is not particularly limited, but the difference (absolute value) in glass transition temperature between the resin fine particles (polymer) A and the resin fine particles (polymer) B is 30 to 100 ° C. As determined.
  • the difference in glass transition temperature (Tg difference) is too low, the difference in thermal stability between the resin fine particles A and the resin fine particles B is small, and one of the scratch resistance or blocking resistance may be inferior.
  • Tg difference absolute value
  • the difference in thermal stability between the resin fine particles A and the resin fine particles B is large, and one of the scratch resistance or blocking resistance may be inferior.
  • the latency may be inferior.
  • the aqueous ink composition of the present invention can have both the latency, the image abrasion resistance and the image blocking resistance.
  • the Tg difference (absolute value) is preferably 40 to 90 ° C., more preferably 40 to 85 ° C., from the viewpoint that both the latency, the image abrasion resistance and the blocking resistance can be achieved at a high level.
  • the Tg of the resin fine particles A and the Tg of the resin fine particles B are not particularly limited as long as they satisfy the above Tg difference (absolute value). From the viewpoint of scratch resistance and blocking resistance of the obtained image, for example, 20 to 150 ° C is preferable, 40 to 130 ° C is more preferable, and 50 to 120 ° C is still more preferable. Either the Tg of the resin fine particles A or the Tg of the resin fine particles B may be high, but the Tg of the resin fine particles A is preferably higher than the Tg of the resin fine particles B. Generally, if Tg is high, the fusibility is inferior.
  • the resin fine particles A have the structural unit (I), they are excellent in fusibility in the ink composition, and are relatively fusible even if Tg is high. There is little deterioration. As a result, it is possible to secure the fusing ability of the resin fine particles B and further improve the abrasion resistance of the image, and further to maintain the high thermal stability of the resin fine particles A and further improve the blocking resistance. it can.
  • the Tg of the resin fine particles A is, for example, preferably 120 ° C. or less, more preferably 115 ° C. or less, and further preferably 110 ° C. or less, from the viewpoint of achieving both the above-described latency and image abrasion resistance and blocking resistance at a high level.
  • the Tg of the resin fine particles B is, for example, preferably 15 ° C. or higher, more preferably 20 ° C. or higher, and further preferably 25 ° C. or higher, from the viewpoint of achieving both the above-described latency and the image abrasion resistance and blocking resistance at a high level.
  • 105 degrees C or less is preferable, 100 degrees C or less is more preferable, 90 degrees C or less is still more preferable, 80 degrees C or less is especially preferable.
  • the glass transition temperatures of the resin fine particles A and the resin fine particles B can be appropriately controlled by a conventionally known method.
  • the glass transition temperature of the resin fine particles is controlled within a desired range by appropriately adjusting the type of monomer used for the synthesis of the polymer constituting the resin fine particles or the composition ratio thereof, the molecular weight of the polymer constituting the resin fine particles, and the like. be able to.
  • the measurement Tg obtained by actual measurement is applied as the glass transition temperature of the resin fine particles.
  • the measurement Tg is measured at 5 ° C./min using a differential scanning calorimeter (DSC) EXSTAR 6220 manufactured by SII Nano Technology
  • the baseline begins to change with the glass transition of the resin fine particles. Measured as the average of the temperature and the temperature returning to baseline again.
  • the calculation Tg calculated by the following calculation formula is applied. Calculation Tg is calculated by the following formula.
  • the weight average molecular weight (Mw) of the resin constituting the resin fine particles used in the present invention is preferably 80,000 or more, more preferably 100,000 to 1,000,000, and further preferably 120,000 to 800,000. preferable. By setting the weight average molecular weight to 80,000 or more, mechanical properties of the obtained film can be further improved.
  • the weight average molecular weight can be measured by a known method using a gel permeation chromatograph (GPC).
  • the polymer constituting the resin fine particles used in the present invention may be either a block copolymer or a random copolymer.
  • the particle size of the resin fine particles used in the present invention is preferably 1 to 400 nm, more preferably 5 to 300 nm, and more preferably 20 to 200 nm from the viewpoint of ink ejection properties. More preferably, it is more preferably 20 to 100 nm, and further preferably 20 to 80 nm.
  • the particle size of the resin fine particles means a volume average particle size. This volume average particle diameter can be measured by the method described in Examples described later.
  • the resin fine particles A are the structural unit (II) selected so that the resin fine particles A and B satisfy the above-described Tg difference (absolute value) as necessary. ) And can be manufactured.
  • the resin fine particles B can be similarly manufactured.
  • a method for producing resin particles a known method can be applied without particular limitation. For example, after polymerization, a cation exchange reaction of Y 1 can be performed.
  • the resin fine particles can be prepared by an emulsion polymerization method.
  • the emulsion polymerization method is a method of preparing resin fine particles by polymerizing an emulsion prepared by adding a monomer, a polymerization initiator, an emulsifier, and a chain transfer agent, if necessary, in an aqueous medium (for example, water). It is.
  • the monomer that leads to the structural unit (I) also functions as an emulsifier. Therefore, it is not necessary to separately mix an emulsifier other than these monomers, but a known emulsifier may be added separately as long as the discharge stability is not lowered.
  • the emulsifier include surfactants (anionic surfactants, nonionic surfactants and cationic surfactants) which may be contained in the aqueous ink composition of the present invention, which will be described later.
  • the polymerization initiator is not particularly limited, and is an inorganic persulfate (eg, potassium persulfate, sodium persulfate, ammonium persulfate, etc.), an azo initiator (eg, 2,2′-azobis (2-amidinopropane) ) Dihydrochloride, 2,2′-azobis [2-methyl-N- (2-hydroxyethyl) -propionamide], 4,4′-azobis (4-cyanovaleric acid)), organic peroxides (eg Peroxypivalate-t-butyl, t-butyl hydroperoxide, disuccinic acid peroxide) and the like, or salts thereof can be used. These can be used alone or in combination of two or more.
  • an inorganic persulfate eg, potassium persulfate, sodium persulfate, ammonium persulfate, etc.
  • an azo initiator eg, 2,2′-azobis (2-amidinopropan
  • the amount of the polymerization initiator used in the present invention is usually 0.01 to 5 parts by mass, preferably 0.2 to 2 parts by mass with respect to 100 parts by mass of all monomers.
  • chain transfer agent known compounds such as carbon tetrahalides, dimers of styrenes, dimers of (meth) acrylic acid esters, mercaptans, sulfides and the like can be used. Of these, dimers of styrenes or mercaptans described in JP-A-5-17510 can be preferably used.
  • the resin fine particles used in the present invention are preferably dispersed in the aqueous medium as described above.
  • the resin fine particles used in the present invention are more preferably self-dispersing resin fine particles.
  • the self-dispersing resin fine particles are fine particles made of a water-insoluble resin that can be dispersed in an aqueous medium by a functional group (particularly an acidic group or a salt thereof, specifically the anionic group) of the resin itself.
  • the dispersed state includes an emulsified state (emulsion) in which a water-insoluble resin is dispersed in a liquid state in an aqueous medium, and a dispersed state (suspension) in which a water-insoluble resin is dispersed in a solid state in an aqueous medium. It includes both states.
  • Water-insoluble means that the amount dissolved in 100 parts by mass of water (25 ° C.) is 5.0 parts by mass or less.
  • the resin fine particles used in the present invention do not function as a pigment dispersant, and therefore do not contain a pigment inside the particles.
  • the water-based ink composition of the present invention preferably has a form in which one or more pigments are dispersed.
  • a normal organic or inorganic pigment can be used.
  • organic pigments include azo pigments, polycyclic pigments, dye chelates, nitro pigments, nitroso pigments, and aniline black.
  • an azo pigment or a polycyclic pigment is preferable.
  • the azo pigment include azo lakes, insoluble azo pigments, condensed azo pigments, and chelate azo pigments.
  • polycyclic pigment examples include phthalocyanine pigments, perylene pigments, perinone pigments, anthraquinone pigments, quinacridone pigments, dioxazine pigments, indigo pigments, thioindigo pigments, isoindolinone pigments, and quinophthalone pigments.
  • dye chelates include basic dye chelates and acid dye chelates.
  • inorganic pigments include titanium oxide, iron oxide, calcium carbonate, barium sulfate, aluminum hydroxide, barium yellow, cadmium red, chrome yellow, and carbon black.
  • pigments described in paragraph numbers 0142 to 0145 of JP-A No. 2007-100071 include the pigments described in paragraph numbers 0142 to 0145 of JP-A No. 2007-100071.
  • the volume average particle size of the pigment in the aqueous ink composition of the present invention is preferably 10 to 200 nm, more preferably 10 to 150 nm, and still more preferably 10 to 100 nm.
  • the volume average particle size is 200 nm or less, the color reproducibility is good, and in the case of the ink jet method, the droplet ejection characteristics are good.
  • light resistance becomes favorable because a volume average particle diameter is 10 nm or more.
  • the volume average particle diameter of the pigment in the aqueous ink composition can be measured by a known measuring method.
  • the particle size distribution of the pigment in the aqueous ink composition of the present invention is not particularly limited, and may be either a wide particle size distribution or a monodisperse particle size distribution. Further, two or more colorants having a monodispersed particle size distribution may be mixed and used.
  • the volume average particle diameter of the pigment can be measured by the same method as the measurement of the volume average particle diameter of the resin fine particles described above.
  • the content of the pigment in the aqueous ink composition is preferably 1 to 20% by mass, more preferably 1 to 10% by mass, from the viewpoint of colorability and storage stability. preferable.
  • the aqueous ink composition of the present invention contains a pigment, as the pigment, colored particles in which the pigment is dispersed in an aqueous medium by a dispersant (hereinafter simply referred to as “colored particles”) are prepared. It is preferable to use it as a raw material.
  • the dispersant may be a polymer dispersant or a low molecular surfactant type dispersant.
  • the polymer dispersant may be either a water-soluble polymer dispersant or a water-insoluble polymer dispersant.
  • low molecular surfactant type dispersant for example, known low molecular surfactant type dispersants described in paragraph numbers 0047 to 0052 of JP2011-178029A can be used.
  • examples of the water-soluble dispersant include hydrophilic polymer compounds.
  • natural hydrophilic polymer compounds include plant polymers such as gum arabic, tragan gum, guar gum, karaya gum, locust bean gum, arabinogalactone, pectin, quince seed starch, seaweeds such as alginic acid, carrageenan and agar.
  • examples include molecules, animal polymers such as gelatin, casein, albumin and collagen, and microorganism polymers such as xanthene gum and dextran.
  • hydrophilic polymer compounds modified from natural products fiber polymers such as methylcellulose, ethylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, carboxymethylcellulose, starch such as sodium starch glycolate and sodium starch phosphate And seaweed polymers such as sodium alginate, propylene glycol alginate, and the like.
  • synthetic hydrophilic polymer compounds include vinyl polymers such as polyvinyl alcohol, polyvinyl pyrrolidone, and polyvinyl methyl ether, non-crosslinked polyacrylamide, polyacrylic acid or alkali metal salts thereof, water-soluble styrene acrylic resins, and the like.
  • Acrylic resin water-soluble styrene maleic acid resin, water-soluble vinyl naphthalene acrylic resin, water-soluble vinyl naphthalene maleic acid resin, polyvinyl pyrrolidone, polyvinyl alcohol, alkali metal salt of ⁇ -naphthalene sulfonic acid formalin condensate, quaternary ammonium, amino And a polymer compound having a salt of a cationic functional group such as a group in the side chain, a natural polymer compound such as shellac, and the like.
  • hydrophilic polymer compound into which a carboxy group is introduced is preferable, such as a homopolymer of acrylic acid or methacrylic acid, a copolymer of acrylic acid or methacrylic acid and another monomer, or the like.
  • the water-insoluble polymer dispersant is a water-insoluble polymer and is not particularly limited as long as the pigment can be dispersed, and a conventionally known water-insoluble polymer dispersant can be used.
  • the water-insoluble polymer dispersant may be configured to include both a hydrophobic structural unit and a hydrophilic structural unit.
  • a monomer component which comprises a hydrophobic structural unit a styrene-type monomer component, an alkyl (meth) acrylate component, an aromatic group containing (meth) acrylate component, etc. can be mentioned.
  • the monomer component constituting the hydrophilic structural unit is not particularly limited as long as it is a monomer component containing a hydrophilic group.
  • the hydrophilic group include a nonionic group, a carboxy group, a sulfonic acid group, and a phosphoric acid group.
  • the nonionic group examples include a hydroxyl group, an amide group (where the nitrogen atom is unsubstituted), a group derived from an alkylene oxide polymer (for example, polyethylene oxide, polypropylene oxide, etc.), a group derived from a sugar alcohol, and the like.
  • the hydrophilic structural unit preferably includes at least a carboxy group, and also preferably includes a nonionic group and a carboxy group.
  • water-insoluble polymer dispersants include styrene- (meth) acrylic acid copolymers, styrene- (meth) acrylic acid- (meth) acrylic acid ester copolymers, (meth) acrylic acid ester- (meta ) Acrylic acid copolymer, polyethylene glycol (meth) acrylate- (meth) acrylic acid copolymer, styrene-maleic acid copolymer, and the like.
  • the water-insoluble polymer dispersant is preferably a vinyl polymer containing a carboxy group from the viewpoint of dispersion stability of the pigment. Furthermore, a vinyl polymer having at least a structural unit derived from an aromatic group-containing monomer as a hydrophobic structural unit and having a structural unit containing a carboxy group as a hydrophilic structural unit is more preferable.
  • the weight average molecular weight of the water-insoluble polymer dispersant is preferably 3,000 to 200,000, more preferably 5,000 to 100,000, and still more preferably 5,000 to 200,000 from the viewpoint of pigment dispersion stability. 80,000, particularly preferably 10,000 to 60,000.
  • the content of the dispersing agent in the colored particles is preferably 10 to 90 parts by mass with respect to 100 parts by mass of the pigment, from 20 to 70 parts from the viewpoint of the dispersibility of the pigment, the ink coloring property, and the dispersion stability. Part by mass is more preferable, and 30 to 50 parts by mass is particularly preferable.
  • the pigment is preferably coated with an appropriate amount of the dispersing agent, and it tends to be easy to obtain colored particles having a small particle size and excellent stability over time.
  • the colored particles can be obtained, for example, by dispersing a mixture containing a pigment, a dispersant, and, if necessary, a solvent (preferably an organic solvent) with a disperser. More specifically, for example, after adding the aqueous solution containing the basic substance (mixing / hydration step) to the mixture of the pigment, the dispersant, and the organic solvent in which the dispersant is dissolved or dispersed, the organic solvent It can be manufactured as a dispersion by providing a step (solvent removal step) except for. As a result, a dispersion of colored particles in which the pigment is finely dispersed and excellent in storage stability can be produced.
  • a solvent preferably an organic solvent
  • the organic solvent needs to be able to dissolve or disperse the dispersant, but in addition to this, it preferably has a certain degree of affinity for water. Specifically, those having a solubility in water at 20 ° C. of 10 to 50% by mass or less are preferable.
  • Preferable examples of the organic solvent include water-soluble organic solvents. Of these, isopropyl alcohol, acetone and methyl ethyl ketone are preferable, and methyl ethyl ketone is particularly preferable.
  • the organic solvent may be used alone or in combination.
  • the above basic substance is used for neutralization of an anionic group (preferably a carboxy group) that the polymer may have.
  • an anionic group preferably a carboxy group
  • the degree of neutralization of the anionic group there is no particular limitation on the degree of neutralization of the anionic group.
  • the liquid property of the finally obtained dispersion of colorant particles is preferably such that the pH is 4.5 to 10, for example.
  • the pH can also be determined by the desired degree of neutralization of the polymer.
  • the removal of the organic solvent in the production process of the colored particle dispersion is not particularly limited, and can be removed by a known method such as vacuum distillation.
  • the colored particles may be used singly or in combination of two or more.
  • the aqueous ink composition of the present invention may contain a surfactant as a surface tension adjusting agent.
  • a surfactant any of an anionic surfactant, a cationic surfactant, an amphoteric surfactant, a nonionic surfactant, and a betaine surfactant can be used.
  • anionic surfactants include sodium dodecylbenzenesulfonate, sodium lauryl sulfate, sodium alkyldiphenyl ether disulfonate, sodium alkylnaphthalenesulfonate, sodium dialkylsulfosuccinate, sodium stearate, potassium oleate, sodium dioctyl.
  • Sulfosuccinate sodium polyoxyethylene alkyl ether sulfate, sodium polyoxyethylene alkyl ether sulfate, sodium polyoxyethylene alkyl phenyl ether sulfate, sodium dialkylsulfosuccinate, sodium oleate, sodium t-octylphenoxyethoxypolyethoxyethyl sulfate, etc. And one or more of these can be selected.
  • nonionic surfactants include, for example, acetylene diol derivatives such as ethylene oxide adducts of acetylene diol, polyoxyethylene lauryl ether, polyoxyethylene octyl phenyl ether, polyoxyethylene oleyl phenyl ether, polyoxyethylene nonyl.
  • examples include phenyl ether, oxyethylene / oxypropylene block copolymer, t-octylphenoxyethyl polyethoxyethanol, nonylphenoxyethyl polyethoxyethanol, and the like, and one or more of these can be selected.
  • cationic surfactants include tetraalkylammonium salts, alkylamine salts, benzalkonium salts, alkylpyridium salts, imidazolium salts, and the like. Specific examples include dihydroxyethyl stearylamine, 2-heptadecenyl. -Hydroxyethyl imidazoline, lauryl dimethyl benzyl ammonium chloride, cetyl pyridinium chloride, stearamide methyl pyridium chloride and the like. Among these surfactants, nonionic surfactants are preferable from the viewpoint of stability, and acetylenic diol derivatives are more preferable.
  • the content of the surfactant in the water-based ink composition is preferably an amount that can bring the water-based ink composition into the range of the following surface tension. More specifically, the content of the surfactant in the aqueous ink composition is preferably 0.1% by mass or more, more preferably 0.1 to 10% by mass, and still more preferably 0.2 to 3% by mass. %.
  • the water-based ink composition of the present invention may further comprise a drying inhibitor (swelling agent), an anti-coloring agent, a penetration accelerator, an ultraviolet absorber, an antiseptic, a rust inhibitor, an antifoaming agent, a clay adjusting agent, if necessary. You may mix additives, such as a pH adjuster and a chelating agent.
  • the mixing method is not particularly limited, and a water-based ink composition of the present invention can be obtained by appropriately selecting a commonly used mixing method.
  • the viscosity of the aqueous ink composition of the present invention at 30 ° C. is preferably 1.2 mPa ⁇ s or more and 15.0 mPa ⁇ s or less, more preferably 2 mPa ⁇ s or more and less than 13 mPa ⁇ s, and still more preferably. It is 2.5 mPa ⁇ s or more and less than 10 mPa ⁇ s.
  • the viscosity of the water-based ink composition is measured at a temperature of 30 ° C. using VISCOMETER TV-22 (manufactured by TOKI SANGYO CO. LTD).
  • the pH of the aqueous ink composition of the present invention is preferably 6 to 11 at 25 ° C. from the viewpoint of dispersion stability.
  • the amount of the surfactant so that the surface tension of the water-based ink composition is 20 to 60 mN / m from the viewpoint of ink ejection properties.
  • the amount is more preferably 20 to 45 mN / m, and still more preferably 25 to 40 mN / m.
  • the surface tension of the aqueous ink composition is measured at a temperature of 25 ° C. using an Automatic Surface Tensiometer CBVP-Z (manufactured by Kyowa Interface Science Co., Ltd.).
  • the image forming method of the present invention includes an ink application step of forming an image by applying the aqueous ink composition of the present invention onto a recording medium by an inkjet method.
  • the image forming method of the present invention includes a step of drying and removing the aqueous medium in the aqueous ink composition applied to the recording medium as necessary (hereinafter also referred to as “ink drying step”), and an aqueous ink composition.
  • Other steps such as a step of melting and fixing resin fine particles contained in the product (hereinafter also referred to as “thermal fixing step”) may be further included.
  • the ink application step is preferably a step of forming an image by directly applying the aqueous ink composition of the present invention on a low water-absorbing recording medium or a non-water-absorbing recording medium.
  • Applying ink directly on a low water-absorbing recording medium or non-water-absorbing recording medium means that the applied ink is in direct contact with the low water-absorbing recording medium or non-water-absorbing recording medium.
  • a treatment liquid known in the field of the image forming method using an aqueous ink composition for the purpose of aggregating components such as resin fine particles contained in the aqueous ink composition is applied in advance, the aqueous ink composition And the low water-absorbing recording medium or the non-water-absorbing recording medium are not in direct contact with each other.
  • Examples of the above-described known processing liquid include processing liquids described in JP 2012-40778 A.
  • the above-described known processing liquid is not applied after the ink application process. That is, it is preferable that the image forming method of the present invention does not include the step of applying the above-described known processing liquid.
  • a precoat liquid or a topcoat liquid is used on the recording medium.
  • a method for improving image quality by aggregating components in a water-based ink composition discharged on the surface and suppressing the spread of the water-based ink composition is known.
  • the water-based ink composition of the present invention exhibits the above-described excellent characteristics and can impart high performance to images, it is possible to provide a low water-absorbing recording medium or non-water-absorbing medium without using a precoat liquid or topcoat liquid. An image with excellent image quality can be formed on the recording medium.
  • the recording medium used in the image forming method of the present invention is not particularly limited, but is preferably a paper medium. That is, general printing paper mainly composed of cellulose, such as so-called high-quality paper, coated paper, and art paper, used for general offset printing or the like can be used.
  • the recording medium commercially available media can be used.
  • Fine coated paper such as “High Quality” (A)
  • fine coated paper such as “Silver Diamond” manufactured by Nippon Paper Industries
  • “OK Everlight Coat” manufactured by Oji Paper and “Aurora S” manufactured by Nippon Paper Industries Lightweight coated paper (A3) such as Koki Paper, “OK Coat L” manufactured by Oji Paper Co., Ltd. and “Aurora L” manufactured by Nippon Paper Industries Co., Ltd.
  • coated paper used for general offset printing or the like is preferable.
  • the coated paper is obtained by applying a coating material to the surface of high-quality paper, neutral paper, etc., which is mainly composed of cellulose and is not generally surface-treated.
  • Coated paper tends to cause quality problems such as glossiness and abrasion resistance of images in normal aqueous inkjet image formation, but uneven glossiness is suppressed when the aqueous ink composition of the present invention is used. As a result, it is possible to obtain an image having good gloss and scratch resistance.
  • the recording medium should be a low water-absorbing recording medium or a non-water-absorbing recording medium.
  • the low water-absorbing recording medium refers to one having an absorption coefficient Ka of water of 0.05 to 0.5 mL / m 2 ⁇ ms 1/2 , and 0.1 to 0.4 mL / m 2 ⁇ m 1/2.
  • ms 1/2 is preferable, and 0.2 to 0.3 mL / m 2 ⁇ ms 1/2 is more preferable.
  • the non-water-absorbing recording medium refers to a medium having a water absorption coefficient Ka of less than 0.05 mL / m 2 ⁇ ms 1/2 .
  • the water absorption coefficient Ka is synonymous with that described in JAPAN TAPPI paper pulp test method No. 51: 2000 (issued by Japan Paper Pulp Technology Association).
  • the absorption coefficient Ka is an automatic scanning absorption meter. It is calculated from the difference in the amount of water transferred between a contact time of 100 ms and a contact time of 900 ms using KM500Win (manufactured by Kumagai Riiki Co., Ltd.).
  • the aqueous ink composition of the present invention containing a pigment is applied onto a recording medium.
  • the application method of the water-based ink composition is not particularly limited as long as the ink-jet method can apply the water-based ink composition on the image, and a known ink application method can be used.
  • the ink jet method has advantages such as a compact recording apparatus and high-speed recording performance.
  • image formation by an ink jet method a water-based ink composition is ejected onto a recording medium by applying energy to form a colored image.
  • the methods described in paragraph numbers 0093 to 0105 of JP-A No. 2003-306623 can be applied.
  • the inkjet method is not particularly limited, and is a known method, for example, a charge control method that discharges ink using electrostatic attraction, a drop-on-demand method (pressure pulse method) that uses vibration pressure of a piezoelectric element, Either an acoustic ink jet method that converts an electrical signal into an acoustic beam, irradiates the ink with ink, and ejects the ink using radiation pressure, or a thermal ink jet method that heats the ink to form bubbles and uses the generated pressure. May be.
  • the ink jet head used in the ink jet method may be an on-demand method or a continuous method.
  • Inkjet methods include a method of ejecting a large number of low-density inks called photo inks in a small volume, a method of improving image quality using a plurality of inks having substantially the same hue and different concentrations, and colorless and transparent inks. The method used is included.
  • a short serial head is used, a shuttle system that performs recording while scanning the head in the width direction of the recording medium, and a line head in which recording elements are arranged corresponding to the entire area of one side of the recording medium
  • a line system using.
  • an image can be recorded on the entire surface of the recording medium by scanning the recording medium in a direction orthogonal to the arrangement direction of the recording elements, and a carriage system such as a carriage for scanning a short head is not necessary.
  • the recording speed can be increased as compared with the shuttle system.
  • the amount of droplets of the aqueous ink composition ejected by the ink jet method is preferably 1.5 to 10 pL, More preferably, it is 6 pL.
  • the droplet amount of the water-based ink composition to be discharged can be adjusted by appropriately adjusting the discharge conditions.
  • the image forming method of the present invention includes an ink drying step of drying and removing an aqueous medium (for example, water, the above-described water-soluble organic solvent) in the aqueous ink composition applied on the recording medium, if necessary. It may be.
  • the ink drying step is not particularly limited as long as at least a part of the aqueous medium in the aqueous ink composition can be removed, and a commonly used method can be applied.
  • the image forming method of the present invention preferably includes a heat fixing step after the ink drying step, if necessary.
  • a heat fixing step By performing the heat fixing process, the image on the recording medium is fixed, and the resistance to image abrasion can be further improved.
  • the heat fixing step for example, the heat fixing step described in paragraph Nos. 0112 to 0120 of JP2010-22215A can be employed.
  • the image forming method of the present invention may include an ink removing step of removing a water-based ink composition (for example, an ink solid material solidified by drying) adhering to the inkjet recording head with a maintenance liquid, if necessary. Good.
  • a water-based ink composition for example, an ink solid material solidified by drying
  • the maintenance liquid and ink removal step described in International Publication No. 2013/180074 can be preferably applied.
  • a monomer solution consisting of methyl methacrylate (31.5 g), styrene (15.0 g), 12-methacrylamide decanoic acid (3.50 g), and isopropyl alcohol (20 g) was added to the three-necked flask for 3 hours.
  • a mixed solution of potassium persulfate (radical polymerization initiator, manufactured by Wako Pure Chemical Industries, Ltd.) (0.26 g) and water (10 g) is added.
  • the mixture was further stirred for 3 hours.
  • An appropriate amount of 1N aqueous potassium hydroxide solution was added to the resulting reaction mixture to adjust the pH to 8.0.
  • the obtained reaction mixture was filtered through a mesh having a mesh size of 50 ⁇ m to prepare an aqueous dispersion of resin fine particles A composed of the polymer A.
  • the obtained aqueous dispersion of resin fine particles A had a pH of 8.0 and a solid content concentration of 20% by mass.
  • the volume average particle diameter of the resin fine particles A in the aqueous dispersion was measured with Microtrac UPA EX-150 (manufactured by Nikkiso Co., Ltd.). The results are shown in Table 1.
  • Table 1 shows the glass transition temperature measured by the following method.
  • the resin comprising the polymer A is the same as the synthesis of the resin fine particles A except that the type and amount of the monomer used are changed to the type and amount of the monomer that leads the structural unit.
  • An aqueous dispersion of microparticles B was prepared.
  • the obtained aqueous dispersion of resin fine particles B had a pH of 8.0 and a solid content concentration of 20% by mass.
  • Table 1 shows the measured values of the volume average particle diameter of the resin fine particles B in the aqueous dispersion by the above-described measuring apparatus and the measured values of the glass transition temperature by the following method, respectively.
  • aqueous dispersion of resin fine particle set P-1 The aqueous dispersion (100 g) of the resin fine particles A and the aqueous dispersion (100 g) of the resin fine particles B are mixed, and the aqueous dispersion (aqueous dispersion) of the resin fine particle set P-1 containing the resin fine particles A and B is mixed.
  • the mass ratio of resin fine particles A to resin fine particles B was 50:50).
  • the obtained aqueous dispersion of resin fine particle set P-1 had a pH of 8.0 and a solid content concentration of 20% by mass.
  • the absolute value of the difference in glass transition temperature between resin fine particles A and resin fine particles B and the longest number of atoms of each structural unit (I) are shown in Table 1 below.
  • the Tg of the resin fine particles was measured as follows. That is, using a sample obtained by drying an aqueous dispersion of resin fine particles, a differential scanning calorimeter (DSC) EXSTAR 6220 manufactured by SII NanoTechnology Co., Ltd. was used to measure at a heating rate of 5 ° C./min. The volume average particle diameter and Tg of the resin fine particles prepared later were also measured by the above measuring apparatus and measuring method.
  • DSC differential scanning calorimeter
  • ⁇ Preparation of aqueous dispersions of resin fine particle sets P-2 to P-13 and CP-1 to CP-7 The type and amount of monomer used in the preparation of the aqueous dispersion of resin fine particle set P-1 are changed to the type and amount of monomer that leads to the structural unit, and the resin in the aqueous dispersion of each resin fine particle set Preparation of aqueous dispersion of resin fine particle set P-1 except that the aqueous dispersion used for each resin fine particle set was mixed in such a ratio that the mass ratio of fine particles A and resin fine particles B became the mass ratio shown in Table 1. In the same manner, aqueous dispersions of resin fine particle sets P-2 to P-13 and CP-1 to CP-7 were obtained.
  • Y 1 was converted to a sodium salt by a conventional method using a sodium salt.
  • the resin fine particle set P-8 is obtained by mixing the aqueous dispersion (140 g) of the resin fine particles A and the aqueous dispersion (60 g) of the resin fine particles B, prepared as described above, to obtain the resin fine particle set P-8. An aqueous dispersion of was obtained.
  • Table 1 shows the physical properties of the obtained resin fine particle sets P-2 to P-13 and CP-1 to CP-7. In Table 1, “-” indicates that measurement is not possible because there are no resin fine particles (polymer) or structural units.
  • Example 1 ⁇ Preparation of water-based ink composition> (Preparation of black ink composition K-1) -Synthesis of water-soluble polymer dispersant Q-1-
  • a monomer feed composition was prepared by mixing methacrylic acid (172 parts), benzyl methacrylate (828 parts), and isopropanol (375 parts).
  • an initiator supply composition was prepared by mixing 2,2-azobis (2-methylbutyronitrile) (22.05 parts) and isopropanol (187.5 parts).
  • isopropanol (187.5 parts) was heated to 80 ° C. under a nitrogen atmosphere, and the mixture of the monomer supply composition and the initiator supply composition was dropped therein over 2 hours.
  • the resulting solution was kept at 80 ° C. for further 4 hours, and then cooled to 25 ° C. After cooling, the solvent was removed under reduced pressure to obtain a water-soluble polymer dispersant Q-1 having a weight average molecular weight of about 30,000 and an acid value of 112 mgKOH / g.
  • This water-soluble polymer dispersant aqueous solution 124 parts
  • carbon black MA-100 (black pigment) 48 parts
  • water (75 parts) and dipropylene glycol (30 parts) are mixed, and a bead mill (beads)
  • a dispersion (uncrosslinked dispersion) of polymer-coated black pigment particles having a pigment concentration of 15% was dispersed until a desired volume average particle size was obtained with a diameter of 0.1 mm ⁇ and zirconia beads).
  • ion-exchanged water is added to the obtained crosslinked dispersion, and the mixture is subjected to ultrafiltration using a stirring ultra holder (manufactured by ADVANTEC) and an ultrafiltration filter (manufactured by ADVANTEC, molecular weight cut off 50,000, Q0500076E ultrafilter). Filtration was performed. After refine
  • the pigment contained in the black pigment dispersion is a polymer-coated pigment (encapsulated pigment) whose surface is coated with a crosslinked polymer obtained by crosslinking the water-soluble polymer dispersant Q-1 with a crosslinking agent.
  • Black pigment dispersion An amount that makes the concentration of the black pigment 4 parts by weight
  • Water-soluble organic solvent 1 Diethylene glycol monohexyl ether (manufactured by Wako Pure Chemical Industries, Ltd.): 3 parts by weight
  • Water-soluble organic solvent 2 Diethylene glycol (sum (Manufactured by Kosei Pharmaceutical Co., Ltd.): 15 parts by mass
  • Aqueous dispersion of the resin fine particle set P-1 solid content concentration: 25% by mass
  • Surfactant Capstone FS-3100 manufactured by DuPont
  • the viscosity of the black ink composition prepared above was in the range of 3 to 15 mPa ⁇ s at 30 ° C. This viscosity was measured with VISCOMETER TV-22 (manufactured by TOKI SANGYO CO. LTD). The surface tension was measured by a platinum plate method using CBVP-Z manufactured by Kyowa Interface Science Co., Ltd. The surface tension of the black ink composition prepared above was in the range of 20 to 60 mN / m.
  • Post-image sample and the two are collectively referred to as "post-image sample”).
  • nozzle omission image omission
  • the ejection rate was determined, and the presence or absence of ejection failure was evaluated according to the following evaluation criteria. In this test, “B” or higher is an acceptable level both after standing for 30 minutes and after standing for 15 hours.
  • the ejection rate (%) was determined from “(number of ejection nozzles in the image sample after being left / number of ejection nozzles in the initial image sample) ⁇ 100”.
  • the discharge rate is 95% or more.
  • ⁇ Abrasion resistance test> The rubbing resistance test was performed for each ink in which the result of latency after standing for 30 minutes in the above ⁇ latency (standability recovery) test> was an evaluation rank “B” or more. That is, for Comparative Examples 2, 3, 6 and 7 in which the latency result after standing for 30 minutes is the evaluation rank “C”, since the ink performance is already poor, no rub resistance test has been performed (in Table 2, “ -") Under the following ink application conditions, a black solid image with a recording duty of 100% was directly formed with a predetermined black ink on a coated paper (trade name “OK Top Coat +”, manufactured by Oji Paper Co., Ltd.) as a recording medium. .
  • a recorded image -Ink application conditions- ⁇ Head: 1,200 dpi (dot per inch) / 20 inch width piezo full line head ⁇ Discharge amount: 2.4 pL -Drive frequency: 30 kHz (recording medium conveyance speed 635 mm / sec) Single pass method The solid image thus formed was left in an environment of 25 ° C. and 50% relative humidity for 24 hours.
  • the surface of the solid image was rubbed 50 times with a Sylphone paper to which a load of 2 ⁇ 10 4 N / m 2 was applied.
  • the state of the rubbing surface of the solid image was visually confirmed, and the rubbing resistance of the image was evaluated according to the following evaluation criteria. In this test, “B” or higher is an acceptable level.
  • -Evaluation criteria- AA Scratch marks could not be confirmed on the rubbing surface, and no image (ink) transfer was observed on the rubbing paper (sylphone paper).
  • ⁇ Blocking resistance test> The blocking resistance test was conducted for each ink in which the result of the latency after standing for 30 minutes in the above ⁇ latency (standability recovery) test> was an evaluation rank “B” or more. That is, for Comparative Examples 2, 3, 6 and 7 in which the latency result after standing for 30 minutes is the evaluation rank “C”, the ink resistance is already poor, and thus the anti-blocking test is not performed (in Table 2, “ -") Under the same ink application conditions as the ink application conditions in the above ⁇ Abrasion resistance test>, a black color is applied with a predetermined black ink on a coated paper (trade name “OK Top Coat +”, manufactured by Oji Paper Co., Ltd.) as a recording medium.
  • a coated paper trade name “OK Top Coat +”, manufactured by Oji Paper Co., Ltd.
  • a solid image with a recording duty of 100% was directly printed. Immediately after printing, it was dried with warm air at 60 ° C. for 2 seconds to obtain a print sample. The print sample was cut into two pieces with a size of 3 cm square. Next, the four printing surfaces were overlapped with each other so that the two printed surfaces face each other. This was placed on a hot plate at 80 ° C. Place a 2.0 cm x 2.0 cm x 0.3 cm flat rubber plate with the 2.0 cm x 2.0 cm side facing the paper side, and further place a 2.0 cm x 2.0 cm face on it A flat plastic plate of 2.0 cm ⁇ 2.0 cm ⁇ 0.3 cm was placed facing the rubber plate. A 500 g weight was placed on the plastic plate and allowed to stand for 1 hour, and then the two overlapped papers were peeled off, and blocking resistance was evaluated according to the following evaluation criteria. In this test, “B” or higher is an acceptable level.

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

Abstract

L'invention concerne : une composition d'encre aqueuse pour enregistrement à jet d'encre qui contient un milieu aqueux et au moins deux types de microparticules de résine, des microparticules de résine A et B ; et un procédé de formation d'image. Le polymère qui forme les microparticules de résine A contient de 1 à 20 % en masse d'un motif structural représenté par une formule spécifique. La valeur absolue de la différence entre les températures de transition vitreuse des microparticules de résine A et B est comprise entre 30 et 100° C.
PCT/JP2018/010773 2017-03-30 2018-03-19 Composition d'encre aqueuse pour enregistrement à jet d'encre, et procédé de formation d'image Ceased WO2018180693A1 (fr)

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JP2020176225A (ja) * 2019-04-19 2020-10-29 株式会社リコー インク、インク収容容器、記録装置、及び記録方法
CN115298038A (zh) * 2020-03-19 2022-11-04 富士胶片株式会社 非浸透性基材用预处理液、油墨组、图像记录用基材、图像记录用基材的制造方法、图像记录物及图像记录方法

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JP2011137138A (ja) * 2009-12-02 2011-07-14 Canon Inc インクジェット記録用インク
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JP2014152207A (ja) * 2013-02-06 2014-08-25 Ricoh Co Ltd インクジェット記録用インク、インクカートリッジ、インクジェット記録装置、画像形成物
JP2016044188A (ja) * 2014-08-19 2016-04-04 花王株式会社 インクジェット記録用水系インク
WO2016159054A1 (fr) * 2015-03-31 2016-10-06 富士フイルム株式会社 Composition aqueuse d'encre, jeu d'encres, procédé de formation d'image, et microparticules de résine

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Publication number Priority date Publication date Assignee Title
JP2004115708A (ja) * 2002-09-27 2004-04-15 Konica Minolta Holdings Inc インクジェット用顔料インク及びインクジェット記録方法
JP2011137138A (ja) * 2009-12-02 2011-07-14 Canon Inc インクジェット記録用インク
JP2013193324A (ja) * 2012-03-19 2013-09-30 Fujifilm Corp 画像記録方法及び画像記録物
JP2014152207A (ja) * 2013-02-06 2014-08-25 Ricoh Co Ltd インクジェット記録用インク、インクカートリッジ、インクジェット記録装置、画像形成物
JP2016044188A (ja) * 2014-08-19 2016-04-04 花王株式会社 インクジェット記録用水系インク
WO2016159054A1 (fr) * 2015-03-31 2016-10-06 富士フイルム株式会社 Composition aqueuse d'encre, jeu d'encres, procédé de formation d'image, et microparticules de résine

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* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2020176225A (ja) * 2019-04-19 2020-10-29 株式会社リコー インク、インク収容容器、記録装置、及び記録方法
JP7279493B2 (ja) 2019-04-19 2023-05-23 株式会社リコー インク、インク収容容器、記録装置、及び記録方法
CN115298038A (zh) * 2020-03-19 2022-11-04 富士胶片株式会社 非浸透性基材用预处理液、油墨组、图像记录用基材、图像记录用基材的制造方法、图像记录物及图像记录方法

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