JP2019081826A - Inkjet ink composition, polymer and production method of the same, and recording method - Google Patents

Abstract

To provide an inkjet ink composition which, while satisfying intermittent discharge stability, has excellent scratch resistance and provides sufficient glossiness when glossiness of a film and the like is required.SOLUTION: The inkjet ink composition comprises a polymer having an acid value of 5 mg KOH/g to 30 mg KOH/g, which comprises: one or more groups selected from a urethane group and a urea group, which are derived from dicyclohexylmethane diisocyanate, isophorone diisocyanate, 1,3-bis(isocyanatomethyl)cyclohexane, m-bis(isocyanatopropyl)benzene, and m-bis(isocyanatomethyl)benzene;and one or more skeletons selected from a skeleton derived from polyoxypropylene glycol and a skeleton derived from polycarbonate diol, which has a weight average molecular weight of 500 to 3000.SELECTED DRAWING: None

Description

  The present invention relates to an inkjet ink composition, a polymer, a method for producing the same, and a method for recording the same.

  The inkjet recording method is used for printing business texts including letters, figures, etc. using plain paper as a recording medium, and the frequency of use for such applications is increasing. In such applications, a high level of color development and fastness of an image (friction, light resistance, ozone gas resistance, water resistance, etc.) are required, so that an ink using a pigment as a coloring material is used. There are many.

  Compared with the ink using a dye as a coloring material, the coloring property of the printed matter printed with the pigment ink is high, but the factor is that the pigment component is easily localized on the surface of the recording medium. The dye penetrates to the inside of the recording medium, but the pigment is coagulated due to the process of the ink adhering to the recording medium or the evaporation or permeation of the vehicle component which occurs after the adhesion. However, the pigment ink has a problem that the abrading property of the printed matter is low because the pigment which is a coloring material is easily present on the surface of the recording medium. In order to improve the rubbing property etc. which are recorded by pigment ink, adding a urethane resin to ink is examined (refer to patent documents 1-3).

JP, 2006-022132, A JP 2012-140602 A JP, 2013-035897, A

  Conventional urethane polymers (particles) contain a large number of polar groups such as hydrophilic groups and urethane groups, and therefore, when used in large amounts in aqueous inks, the viscosity increases. In the ink jet printing, when the viscosity increases, the discharge becomes unstable and clogging easily occurs, so the amount of the resin added is limited, and sufficient fixing property and scratch resistance can not be obtained. In addition, when printing on media such as films where gloss is required, the gloss is low.

  In addition, when recording is performed by the inkjet recording method, evaporation of water in the ink occurs from the nozzles if the ink is not discharged from the nozzles of the injet head for a certain period of time. After that, when it is attempted to eject the next ink from the nozzle, the ink droplets may not fly straight or may not be ejected. The ink in which such a phenomenon occurs has low intermittent discharge stability.

  For example, the ink described in Patent Document 1 uses an allophanate-modified urethane resin to which polyethylene glycol monomethyl ether is added as a pigment dispersant. The ink described in Patent Document 2 is a pigment ink to which a urethane resin modified with an allophanate to which polyethylene glycol monomethyl ether is added is added. All of these inks have insufficient intermittent ejection stability and scratch resistance of the recorded image.

Further, the ink described in Patent Document 3 uses a urethane resin modified with isocyanurate. Such inks have the resistance to scratching, clogging and OPP of recorded images.
The glossiness when printed on a film was low.

  As described above, an ink capable of recording an image excellent in intermittent discharge stability and excellent in abrasion resistance and glossiness, and a polymer suitable for an inkjet ink have not been found yet.

  Therefore, one of the objects according to some aspects of the present invention is that it is excellent in abrasion resistance while satisfying intermittent discharge stability, and that sufficient glossiness is obtained even when the glossiness of a film or the like is required. It is an object of the present invention to provide an inkjet ink composition, a polymer, a method for producing the same and

  The present invention has been made to solve at least a part of the problems described above, and can be realized as the following aspects or application examples.

One aspect of the inkjet ink composition according to the present invention is
A group derived from one or more selected from dicyclohexylmethane diisocyanate, isophorone diisocyanate, 1,3-bis (isocyanatomethyl) cyclohexane, m-bis (isocyanatopropyl) benzene and m-bis (isocyanatomethyl) benzene; And at least one group selected from a urethane group and a urea group,
At least one skeleton selected from a skeleton derived from polyoxypropylene glycol and a skeleton derived from polycarbonate diol, containing a skeleton having a weight average molecular weight of 500 to 3,000,
It contains a polymer having an acid value of 5 mg KOH / g or more and 30 mg KOH / g or less.

  According to such an inkjet ink composition, while satisfying intermittent discharge stability, it is excellent in abrasion resistance, and sufficient glossiness is obtained even when the glossiness of a film or the like is required. That is, all of dicyclohexylmethane diisocyanate, isophorone diisocyanate, 1,3-bis (isocyanatomethyl) cyclohexane, m-bis (isocyanatopropyl) benzene and m-bis (isocyanatomethyl) benzene are polymerized at the position where the isocyanate group is bonded. When it becomes a polymer, it is in a position where it is difficult to crystallize or stack, so an image excellent in abrasion resistance and gloss can be formed. Further, since the acid value is 5 mgKOH / g or more and 30 mgKOH / g or less, the interaction with other components (water, pigment, etc.) contained in the inkjet ink composition is in an appropriate range. Thereby, good intermittent discharge stability can be secured.

  In addition, since the polymer contains one or more kinds of skeletons selected from a skeleton derived from polyoxypropylene glycol and a skeleton derived from polycarbonate diol, the scratch resistance of the obtained image can be made favorable. Furthermore, since the weight average molecular weight of at least one skeleton selected from the skeleton derived from polyoxypropylene glycol and the skeleton derived from polycarbonate diol is 500 or more and 3,000 or less, the flexibility of the solidified product of the inkjet ink composition is good. It becomes.

In the inkjet ink composition according to the present invention,
The polymer may contain a skeleton derived from a carboxyl group-containing glycol.

  According to such an inkjet ink composition, the acid value can be easily made 5 mg KOH / g or more and 30 mg KOH / g or less. In addition, the fixability to the recording medium of the formed image can be further improved.

In the inkjet ink composition according to the present invention,
The skeleton derived from the carboxyl group-containing glycol may be a skeleton derived from dimethylol propionic acid.

  According to such an inkjet ink composition, the acid value can be easily made 5 mg KOH / g or more and 30 mg KOH / g or less. In addition, the fixability to the recording medium of the formed image can be further improved.

In the inkjet ink composition according to the present invention,
The polymer may contain one or more types of skeleton selected from a skeleton derived from an aliphatic diamine and a skeleton derived from an aromatic diamine.

  According to such an inkjet ink composition, the flexibility of the solidified product of the inkjet ink composition is further improved, and the fixability and the abrasion resistance of the image can be further improved.

In the inkjet ink composition according to the present invention,
The polymer may contain a skeleton derived from an alkyl diamine having 1 to 8 carbon atoms.

  According to such an inkjet ink composition, the flexibility of the solidified product of the inkjet ink composition is further improved, and the fixability and the abrasion resistance of the image can be further improved.

In the inkjet ink composition according to the present invention,
It may further contain a lactam.

In the inkjet ink composition according to the present invention,
The lactam may comprise 2-pyrrolidone.

One aspect of the polymer according to the present invention is
A group derived from one or more selected from dicyclohexylmethane diisocyanate, isophorone diisocyanate, 1,3-bis (isocyanatomethyl) cyclohexane, m-bis (isocyanatopropyl) benzene and m-bis (isocyanatomethyl) benzene; And at least one group selected from a urethane group and a urea group,
At least one skeleton selected from a skeleton derived from polyoxypropylene glycol and a skeleton derived from polycarbonate diol, containing a skeleton having a weight average molecular weight of 500 to 3,000,
An acid value is 5 mgKOH / g or more and 30 mgKOH / g or less.

  If such a polymer is applied to an inkjet ink, it is excellent in abrasion resistance while satisfying intermittent discharge stability, and sufficient glossiness can be obtained even when the glossiness of a film or the like is required. That is, all of dicyclohexylmethane diisocyanate, isophorone diisocyanate, 1,3-bis (isocyanatomethyl) cyclohexane, m-bis (isocyanatopropyl) benzene and m-bis (isocyanatomethyl) benzene are polymerized at the position where the isocyanate group is bonded. When it becomes a polymer, it is in a position where it is difficult to crystallize or stack, so an image excellent in abrasion resistance and gloss can be formed. Further, since the acid value is 5 mgKOH / g or more and 30 mgKOH / g or less, the interaction with other components (water, pigment, etc.) contained in the inkjet ink composition is in an appropriate range. Thereby, good intermittent discharge stability can be secured.

One aspect of the method for producing a polymer according to the present invention is
It is a manufacturing method to be reacted in a solvent containing 2-pyrrolidone, which is dicyclohexylmethane diisocyanate, isophorone diisocyanate, 1,3-bis (isocyanatomethyl) cyclohexane, m-bis (isocyanatopropyl) benzene and m-bis (isocyanate methyl) It forms a polymer having one or more groups selected from a urethane group and a urea group, which is a group derived from one or more types selected from benzene.

  According to such a manufacturing method, a polymer can be easily and stably manufactured, and when applied to an inkjet ink, it is excellent in abrasion resistance and sufficient even when the gloss of a film or the like is required. An inkjet ink composition capable of easily forming an image having glossiness can be produced.

  Hereinafter, some embodiments of the present invention will be described. The embodiment described below is an example of the present invention. The present invention is not limited to the following embodiments at all, and includes various modifications implemented without departing from the scope of the present invention. Note that not all of the configurations described below are necessarily essential configurations of the present invention.

1. Ink Jet Ink Composition The ink jet ink composition of the present embodiment contains a polymer. After describing the polymer first, the other components will be described.

1.1. Polymer The inkjet ink composition of the present embodiment is selected from dicyclohexylmethane diisocyanate, isophorone diisocyanate, 1,3-bis (isocyanatomethyl) cyclohexane, m-bis (isocyanatopropyl) benzene and m-bis (isocyanatemethyl) benzene The polymer is a group derived from one or more types, and contains a polymer having one or more types selected from a urethane group and a urea group.

1.1.1. Overview of Polymer The polymer contained in the inkjet ink composition of the present embodiment includes dicyclohexylmethane diisocyanate, isophorone diisocyanate, 1,3-bis (isocyanate methyl) cyclohexane, m-bis (isocyanate propyl) benzene and m-bis It has at least one group (linkage) selected from a urethane group (urethane bond) and a urea group (urea bond) derived from one or more diisocyanates selected from isocyanatomethyl) benzene. Therefore, in the present specification, it can be referred to as a urethane resin (polyurethane).

  The polymer contained in the inkjet ink composition of the present embodiment is a resin polymerized using a polyisocyanate, but is polymerized at least using a polyisocyanate and a polyol or a polyamine, and a cross-linking agent or the like as necessary. It is polymerized using a polyol or polyamine as a chain extender.

  The polymer is at least one group selected from a urethane bond (urethane group) in which an isocyanate group and a hydroxyl group are reacted, and a urea bond (urea bond) (urea group) generated by a reaction of an isocyanate group and an amino group. And may be linear or branched.

Further, the term "polymer" includes those having thermoplasticity, and those having a crosslinked structure and showing no or little Tg or melting point, regardless of the presence or absence of a crosslinked structure.

  An isocyanate group for forming a urethane bond is supplied from a compound containing an isocyanate group. Moreover, the hydroxyl group (hydroxyl group) for forming a urethane bond is supplied from the compound containing a hydroxyl group. And in order to polymerize, the compound which has an isocyanate group has a 2 or more isocyanate group, and the compound which has a hydroxyl group is selected and the thing which has a 2 or more hydroxyl group is selected and superposed | polymerized. In the present specification, a compound having two or more isocyanate groups may be referred to as a polyisocyanate, and a compound having two or more hydroxyl groups may be referred to as a polyol. Among these, a compound having two isocyanate groups may be referred to as a diisocyanate, and a compound having two hydroxyl groups may be referred to as a diol.

  In addition, the molecular chain between the isocyanate group of the polyisocyanate and the molecular chain between the hydroxyl group of the polyol and the amino group of the polyamine is not a urethane bond or a urea bond when it becomes a polyurethane. Part of the In the present specification, all or part of the portion other than the urethane bond or the urea bond when it becomes a polyurethane may be referred to as a skeleton. The backbone may be linear, branched.

  In addition, the polymer may contain a bond other than a urethane bond and a urea bond, and as such a bond, a reaction of a urea bond and a urea bond and an isocyanate group which are generated by the reaction of a plurality of isocyanate bonds with water. These include a burette bond produced by the reaction, an alphanate bond produced by the reaction of a urethane bond and an isocyanate group, a uretdione bond by dimerization of an isocyanate group, and an isocyanurate bond by trimerization of an isocyanate group. These bonds can be generated positively or not by the reaction temperature or the like. Thus, for example, when polyisocyanate, polyol and polyamine coexist, a polymer containing these bonds (groups) in addition to urethane bonds and urea bonds can be formed. By having the allophanate structure, the biuret structure, the uretdione structure and the isocyanurate structure, the adhesion to the medium may be increased, the film strength may be increased, and the scratch resistance may be improved.

  In the present specification, also for polyamine, a compound having two or more amino groups is referred to as a polyamine and is the same as the above-mentioned polyisocyanate and polyol.

1.1.2. Polymeric Raw Material The polymer of the present embodiment is obtained by polymerization using at least a diisocyanate and a polyol, but the polymer used in the inkjet ink composition according to the present embodiment may be polymerized using a polyamine. It is also possible to use, for example, a polyol, a polyamine as a crosslinking agent or a chain extender, or the like, if necessary.

1.1.2.1. Diisocyanate The diisocyanate used in the polymer of this embodiment is dicyclohexylmethane diisocyanate, isophorone diisocyanate, 1,3-bis (isocyanatomethyl) cyclohexane, m-bis (isocyanatopropyl) benzene and m-bis (isocyanatomethyl) benzene One or more selected.

  The chemical structures of these diisocyanates are shown below. Moreover, since these diisocyanates can be variously named by common names etc., they all have many aliases. Therefore, in place of the alias notation, the CAS number is written together.

  Dicyclohexylmethane diisocyanate: CAS = 5124-30-1

  Isophorone diisocyanate: CAS = 4098-71-9

  1,3-Bis (isocyanatomethyl) cyclohexane: CAS = 38661-72-2

  m-Bis (isocyanatopropyl) benzene: CAS = 2778-42-9

  m-Bis (isocyanatomethyl) benzene: CAS = 3634-83-1

  When these diisocyanates are polymerized to form a bond with, for example, a hydroxyl group (hydroxyl group) or an amino group to form a polymer, the cyclohexyl ring or the benzene ring can be bonded at such a position that it is difficult to stack or crystallize. Thus, the polymer (urethane resin) can be prevented from excessively increasing the density of the microphase separation structure or the cross-linked structure of the microcrystal. Therefore, the Tg (glass transition temperature) of the polymer can be lowered, and the flexibility of the polymer can be increased. Thus, when the ink jet ink composition is attached to the recording medium, the abrasion resistance of the image can be improved, and an image having sufficient gloss can be formed.

  In addition, as for isophorone diisocyanate, 1,3-bis (isocyanatomethyl) cyclohexane, m-bis (isocyanatopropyl) benzene and m-bis (isocyanate methyl), an isocyanate group is disposed at the meta position of the six-membered ring ( Because of the 1,3-arrangement), the cyclohexyl ring or benzene ring is polymerized so as to form a structure that is difficult to stack or crystallize. Therefore, when these are polymerized to form a polymer (urethane resin), it is possible to prevent the density of the microphase separation structure or the cross-linked structure of microcrystalline from being excessively increased.

Further, dicyclohexylmethane diisocyanate may be either a mixture of dicyclohexylmethane 4,4'-diisocyanate, a mixture of dicyclohexylmethane 2,2'-diisocyanate and dicyclohexylmethane 2,4'-diisocyanate and each single substance thereof. Furthermore, you may use as polyfunctional isocyanate which consists of a dimer or more of these arbitrary combinations. A polyfunctional polyisocyanate is a compound having a structure composed of two or more molecules of polyisocyanate and having two or more isocyanate groups at the end of the molecule in order to react with OH groups and NH ₂ groups such as polyols and polyamines. . These polyfunctional polyisocyanates may include at least one selected from the group consisting of allophanate structures, uretdione structures, isocyanurate structures and biuret structures.

  The polyfunctional polyisocyanate is a structure composed of a monomeric diisocyanate and a polyisocyanate of two or more molecules of polymeric, and is preferably one having many branches in the molecule. In a polymer having a structure composed of such a polyfunctional polyisocyanate, a structure in which molecules are sterically complicated and entangled with each other, and a state in which urethane bonds are closely packed. Therefore, even if the acid value is relatively low, it can be stably dispersed in a water-based ink. By using these polyisocyanates, while ensuring the intermittent discharge stability, the scratch resistance and the scratch resistance which can record an image excellent in gloss when printed on a film are improved.

1.1.2.2. Polyol The polymer contained in the inkjet ink composition of the present embodiment can use a polyol as a raw material. The polyol is not particularly limited as long as it is a compound having two or more functional groups, that is, two or more hydroxyl groups. Examples of the polyol include alkylene glycol, polyester polyol, polyether polyol, polycarbonate diol and the like.

  As the alkylene glycol, ethylene glycol, diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol, 1,2-propylene glycol, 1,3-propanediol, tripropylene glycol, polypropylene glycol, (poly) tetramethylene glycol, hexa Methylene glycol, tetramethylene glycol, neopentyl glycol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 1,2-pentanediol, 1,5-pentanediol, 1,2- Hexanediol, 1,6-hexanediol, 3-methyl-1,5-pentanediol, 1,2-cyclohexanediol, 1,4-cyclohexanediol, 1,4-cyclohexanediyl Tanol, 4,4-dihydroxyphenylpropane, 4,4-dihydroxyphenylmethane, glycerin, trimethylolethane, trimethylolpropane, 1,2,5-hexanetriol, 1,2,6-hexanetriol, pentaerythritol, triol Methylolmelamine, polyoxypropylene triol, dimethyl-1,3-pentanediol, diethyl-1,3-pentanediol, dipropyl-1,3-pentanediol, dibutyl-1,3-pentanediol, 2-butyl-2- Ethyl 1,3-propanediol and the like.

  When an alkylene glycol is used as a raw material of a polymer, an alkylene glycol having a small molecular weight intrudes into a three-dimensional network structure formed in the polymer to react with an isocyanate to form a urethane bond to obtain a stronger film. May be As a result, the strength of the film (image) may be strengthened and the abrasion resistance may be further improved.

  As polyester polyol, an acid ester etc. are mentioned. Examples of acid components constituting the acid ester include malonic acid, succinic acid, tartaric acid, oxalic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, alkylsuccinic acid, linolenic acid, maleic acid, fumaral Examples thereof include acids, aliphatic dicarboxylic acids such as mesaconic acid, citraconic acid and itaconic acid, phthalic acids, naphthalenedicarboxylic acids, biphenyldicarboxylic acids, tetrahydrophthalic acids, and alicyclic dicarboxylic acids such as aromatic hydrogenates. Anhydrides, salts, alkyl esters, acid halides and the like of these acid components can also be used as the acid component. Moreover, it does not specifically limit as an alcohol component which comprises an acid ester, The above-mentioned diol compound can be illustrated.

  Examples of polyether polyols include addition polymers of alkylene oxide, and condensation polymers of polyols such as (poly) alkylene glycol. Examples of the alkylene oxide include ethylene oxide, propylene oxide, butylene oxide and α-olefin oxide. And as (poly) alkylene glycol, polyethylene glycol (polyoxyethylene glycol), polypropylene glycol (polyoxypropylene glycol), polybutylene glycol etc. are mentioned. Among these, when polyoxypropylene glycol is used, the flexibility of the polymer (urethane resin) can be improved, and the abrasion resistance and the glossiness when printed on a film can be improved. As the polyoxypropylene glycol, commercially available products can be used, and examples thereof include Exenol series manufactured by Asahi Glass Co., Ltd., Newpol PP series manufactured by Sanyo Kasei Co., Ltd., Uniol D series manufactured by NOF Corporation, and the like.

  The polycarbonate diol contains a molecular chain having two hydroxyl groups and a carbonate bond.

Examples of polycarbonate diols that can be used as part or all of polyols in this embodiment include polycarbonate diols obtained by reacting carbonate components such as alkylene carbonate, diaryl carbonate, and dialkyl carbonate, phosgene, and aliphatic polyol components. Further, alkanediol-based polycarbonate diols such as polyhexamethylene carbonate diol can be mentioned. When polycarbonate diol is used as the starting material for the polymer, the heat resistance and hydrolysis resistance of the produced polymer tend to be good.

  By using a polycarbonate diol as the polyether, the polymer has a skeleton derived from the polycarbonate diol, so that the abrasion resistance of the obtained image can be further improved.

  The polycarbonate diol suitable as a raw material of the polymer of this embodiment generally has two hydroxyl groups in the molecule, and can be obtained by transesterification of a diol compound and a carbonic ester. Such diol compounds include, for example, 1,4-butanediol, 1,3-butanediol, 1,2-butanediol, 1,5-pentanediol, 1,2-pentanediol, 1,6-hexanediol, 1 5-hexanediol, 1,2-hexanediol, 1,7-heptanediol, 1,8-octanediol, 1,2-octanediol, 1,9-nonanediol, 1,10-decanediol, neopentyl Glycol, 4-methyl-1,5-pentanediol, 2-methyl 1,3-propanediol, 2-methyl-1,8-octanediol, 2-isopropyl-1,4-butanediol, 2-ethyl-1 , 6-hexanediol, 3-methyl-1,5-pentanediol, 2,4-dimethyl-1,5-pentanediol, 2 4-diethyl-1,5-pentanediol, 1,3-butanediol, 2-ethyl-1,3-hexanediol, 2-butyl-2-ethyl-1,3-propanediol, 1,4-cyclohexanedilide Methanol, 1,3-cyclohexanediol, 1,4-cyclohexanediol and the like can be mentioned. These can be used alone or in combination of two or more. Among the above-mentioned diols, neopentyl glycol, 4-methyl-1,5-pentanediol, 2-methyl 1,3-propanediol, 2-methyl-1,8-octanediol, 2-methyl-1,5-pentanediol, 2- (1,2-propanediol), which hardly crystallizes Isopropyl-1,4-butanediol, 2-ethyl-1,6-hexanediol, 3-methyl-1,5-pentanediol, 2,4-dimethyl-1,5-pentanediol, 2,4-diethyl- More preferred is 1,5-pentanediol.

  Carbonic esters that can be used to produce polycarbonate diols include, but are not limited to, dialkyl carbonates, diaryl carbonates, or alkylene carbonates, as long as the effects of the present invention are not impaired. Among these, diaryl carbonate is preferable from the viewpoint of reactivity. Specific examples of the carbonate compound include dimethyl carbonate, diethyl carbonate, dibutyl carbonate, diphenyl carbonate, ethylene carbonate and the like, and diphenyl carbonate is more preferable.

  As commercial products of polycarbonate diol, for example, Mitsubishi Chemical's BENE BiOL series NL1010 DB, NL 2010 DB, NL 3010 DB, NL 1010 B, NL 2010 B, NL 3010 B, NL 1050 DB, NL 2050 DB, NL 3050 DB, Asahi Kasei Chemicals Duranol series, Tosoh Nipporan series, Kuraray poly There are hexanediol carbonate, Plaxel series made by Daicel Chemical Industries, CDCD 205 PL, ETERNACOLL series made by Ube Industries, etc.

  When using a polyol as a raw material of the polymer contained in the inkjet ink composition of this embodiment, it is more preferable that an acid group exists in the molecule | numerator of a polyol. Examples of the acid group-containing diol include dimethylol acetic acid, dimethylol propionic acid, dimethylol butanoic acid and dimethylol butyric acid. Among these, dimethylol propionic acid and dimethylol butanoic acid are more preferable. When the inkjet ink composition of the present embodiment is a water system, the polymer is more preferably polymerized using such an acid group-containing diol as a raw material.

  Moreover, when using polyoxypropylene glycol and / or polycarbonate diol as a raw material of a polymer, it is preferable that the weight average molecular weights of all are 500 or more and 3000 or less. When the weight average molecular weight is 500 or more, the density of the urethane bond in the polymer is not excessively increased, and rigidity of a molecular chain derived from polyoxypropylene glycol and / or polycarbonate diol can be suppressed. As a result, the flexibility of the polymer is enhanced and the scratch resistance of the image is improved. In addition, if the weight average molecular weight of polyoxypropylene glycol and / or polycarbonate diol that reacts with polyisocyanate is 3,000 or less, the density of urethane bonds in the polymer does not become too small, and polyoxypropylene glycol and / or polycarbonate diol are obtained. Since the extensibility of the molecular chain from which it originates is not increased too much and the flexibility of the polymer is suppressed, tackiness is unlikely to occur, and scratch resistance can be secured. Therefore, when the weight average molecular weight of the polyoxypropylene glycol and / or the polycarbonate diol is 500 or more and 3,000 or less, the balance between the strength and the flexibility of the film (image) formed of the polymer is improved, and thus recording is performed. The scratch resistance of the image can be made good.

  Therefore, when the weight average molecular weight of the polycarbonate diol is 500 to 3,000, the balance between the strength and the flexibility of the polymer film is improved, so that the scratch resistance of the image to be recorded can be made to a particularly high level.

  A polymer polymerized using such components is mainly composed of two types of segments, hard segment and soft segment. The hard segment is composed of polyisocyanate, short-chain polyol, polyamine, crosslinking agent, chain extender and the like, and mainly contributes to the strength of the polymer. On the other hand, the soft segment is composed of a long chain polyol or the like and is considered to mainly contribute to the flexibility of the resin. Then, the ink jet ink composition is attached to the recording medium, and the film formed of such a polymer has both of strength and flexibility since the hard segment and soft segment have a microphase separation structure, and has high elasticity. The Such film properties contribute to the improvement of the scratch resistance of the recorded matter.

1.1.2.3. Other starting materials (polyamines)
The polymeric raw material contained in the inkjet ink composition of the present embodiment may contain a polyamine. The polyamine is not particularly limited as long as it is a compound having a difunctional or higher amino group.

Examples of polyamines include ethylenediamine, propylenediamine, 2,2-dimethyl-1,3-propanediamine, 2-methyl-1,5-pentanediamine, trimethylhexanediamine, 2-butyl-2-ethyl-1,5-pentane Aliphatic diamines (alkyl diamines) such as diamine, 1,8-octane diamine, 1,9-nonane diamine, 1,10-decane diamine, diethylene triamine, hexylene diamine, triethylene tetramine, tetraethylene pentamine, isophorone diamine, xylin Diazinamine, diphenylmethanediamine, hydrogenated diphenylmethanediamine, hydrazine, polyamidepolyamine, polyethylenepolyimine, 1-amino-3-aminomethyl-3,5,5-trimethylcyclohexane, dicyclohexyl Tanjiamin, bicycloheptane di methanamine, menthenediamine, diaminodicyclohexylmethane, isoproterenol kink Chin cyclohexyl-4,4'-diamine, 1,4-diaminocyclohexane, and the like 1,3-bis-aminomethyl cyclohexane. Among these, C1 or more and 8 or less alkyl diamine and aromatic diamine are more preferable. In addition, many compounds generally used as polyamines have molecular weights equivalent to those of short-chain polyols, and basically, they become urea groups or biuret groups which are hard segments of a polymer.

  In addition, although a polyamine can be used also as a component made to react with polyfunctional polyisocyanate, a chain extender, a crosslinking agent, etc., when an isocyanate group and an amino group are made to react, a urea bond is formed. Therefore, in the case of using a polyamine, the amount used can be determined so that the ratio of urea group / urethane group in the polymer becomes a desired ratio, and the physical properties of the polymer can be controlled.

  In the polymer, as a method of adjusting the ratio of urea group / urethane group, a method of adjusting the amount to be used while considering the equivalent of the amino group of the amine compound (polyamine) at the time of synthesizing the polymer There is a method of adjusting the residual ratio of unreacted isocyanate groups when phase inversion is performed.

  In the method of adjusting the amount of polyamine used when synthesizing the polymer, the amount of urea bond generated by the reaction of the polyamine and the isocyanate group is controlled. First, different amounts of polyamine are used to synthesize multiple types of polymers, and the ratio of urea group / urethane group is calculated. From the obtained molar ratio, the relationship between the amount of polyamine used and the molar ratio is examined to create a calibration curve, and this calibration curve is used to synthesize a polymer having a desired molar ratio. Determine the amount of polyamine used. The calibration curve is prepared in advance even if the same type of polyamine is used, since the reaction rate may change if the other components are different, and therefore the molar ratio does not become the same.

  In addition, as a method of adjusting the residual ratio of unreacted isocyanate groups when phase-inverting a polymer to water, first, a Fourier transform infrared spectrometer (FT- The residual ratio of isocyanate group to the amount of polyisocyanate used is confirmed by IR). The residual ratio of isocyanate groups can be adjusted by changing the reaction time, the amount of polyisocyanate used, and the like.

(Crosslinking agent and chain extender)
The polymer of the present embodiment may contain a crosslinking agent and / or a chain extender.
The crosslinking agent is used during the synthesis of the prepolymer, and the chain extender is used when performing the chain extension reaction after the synthesis of the prepolymer. The crosslinking agent and the chain extender can be appropriately selected from the above-mentioned polyisocyanates, polyols, polyamines and the like depending on applications such as crosslinking and chain extension.

  The chain extender is, for example, a compound to be reacted with an isocyanate group of one of the above-mentioned polyisocyanates which does not form a urethane bond. As a compound which can be used as a chain extender, the above-mentioned polyol, a polyamine, etc. are mentioned. Further, as a chain extender, one capable of crosslinking a polymer can also be used. Examples of the compound which can be used as a chain extender include low molecular weight polyols and polyamines having a number average molecular weight of less than 500.

  Moreover, as a crosslinking agent, the thing of trifunctional or more is mentioned among polyisocyanate, a polyol, and a polyamine. Examples of trifunctional or higher polyfunctional polyisocyanates include polyisocyanates having an isocyanurate structure, and polyisocyanates having an allophanate or biuret structure. As the polyol, glycerin, trimethylolpropane, pentaerythritol, polyoxypropylene triol or the like can be used. Examples of the trifunctional or higher polyamines include trialcohol amines such as triethanolamine and triisopropanolamine, and amines having an amino group with trifunctional or higher such as diethylene triamine and tetraethylene pentamine.

  The presence or absence of crosslinking of the polymer is determined by the gel fraction calculated by calculating the ratio of the gel content to the sol content using a phenomenon in which the polymer having a crosslinked structure does not dissolve in the solvent and swells. be able to. The gel fraction is an index of the degree of crosslinking measured from the solubility of the solidified polymer, and the gel fraction tends to be higher as the degree of crosslinking is higher.

(Isocyanate other than diisocyanate)
The polymer contained in the inkjet ink composition of this embodiment may use isocyanate other than the above-mentioned diisocyanate as a raw material in the range which does not inhibit the above-mentioned function and effect. Such isocyanates include, for example, aliphatic polyisocyanates, aromatic polyisocyanates, and alicyclic polyisocyanates.

  Aliphatic polyisocyanates include tetramethylene diisocyanate, hexamethylene diisocyanate, dodecamethylene diisocyanate, 2,2,4-trimethylhexamethylene diisocyanate, 2,4,4-trimethylhexamethylene diisocyanate, lysine diisocyanate, 2-methylpentane-1 Examples thereof include polyisocyanates having a chain structure such as 5-diisocyanate, 3-methyl-1,5-pentane diisocyanate and the like.

  Aromatic polyisocyanates can also be used. Examples thereof include tolylene diisocyanate, 1,4-phenylene diisocyanate, 1,5-naphthylene diisocyanate and the like. When an aromatic polyisocyanate is used, a blocked alicyclic polyisocyanate in which 80% or more of the aromatic ring of the aromatic polyisocyanate is hydrogenated may be used.

  Examples of alicyclic polyisocyanates include 1,4-cyclohexane diisocyanate, hydrogenated xylylene diisocyanate (hydrogenated XDI) and the like.

  By using these polyisocyanates, the strength of the formed film may be increased, and the abrasion resistance may be improved. In particular, when the above-mentioned alicyclic polyisocyanate and alicyclic polyisocyanate are used, the film strength may be further enhanced and the scratch resistance may be further improved. Moreover, you may mix and use multiple types of these polyisocyanate.

  Moreover, the structure which consists of polyisocyanate of 2 molecules or more may be sufficient as polyisocyanate. The structure composed of two or more molecules of polyisocyanate is, for example, a uretdione structure or an isocyanurate structure. If such a polyisocyanate is selected, the polymer has a structure in which the molecules are intricately intertwined sterically, and a state in which the urethane bonds are dense. Therefore, for example, even with a low acid value, it can be stably dispersed in a water-based ink.

  Generally, the decrease in intermittent discharge stability is caused by the evaporation of water from the nozzle of the ink jet head. In order to improve the intermittent discharge stability, the pigment and resin aggregate even when water interacts to some extent from the ink composition present in the vicinity of the nozzle of the ink jet head and the interaction between the polymer and the pigment is enhanced. It is one of the elements to keep the state dispersed stably. Although the polymer of the present embodiment has a relatively low acid value, it has a sterically complex complex by including the structure of the above-mentioned polyisocyanate, so even if the evaporation of water proceeds, the polymer and the pigment become complex It is easy to produce repulsion by electrostatic action or repulsive force between them, and it is easy to obtain a stable dispersion structure.

As used herein, the backbone of a polymer refers to the molecular chains between functional groups. Therefore, the polymer of the present embodiment has a skeleton derived from the molecular chain of the raw material such as polyisocyanate, polyol, or polyamine. The other skeleton is not particularly limited, and is, for example, a substituted or unsubstituted saturated, unsaturated or aromatic chain, and such a chain may have a carbonate bond, an ester bond, an amide bond, etc. . Moreover, the kind and number of substituents in the skeleton are not particularly limited, and an alkyl group, a hydroxyl group, a carboxyl group, an amino group, a sulfonyl group, a sulfonyl group, and the like may be included.

1.1.3. Polymer synthesis and analysis (polymer synthesis)
The polymer used for the inkjet ink composition of the present embodiment can be synthesized using a method known as a polymer polymerization method. An example will be given below to explain. The polyisocyanate and a compound (polyol and, if necessary, a polyamine etc.) to be reacted therewith are reacted in an amount used to increase the number of isocyanate groups to polymerize the prepolymer having isocyanate groups at the molecular ends. At this time, if necessary, an organic solvent having a boiling point of 100 ° C. or less such as methyl ethyl ketone, acetone or tetrahydrofuran may be used. This is generally referred to as the prepolymer method.

  When an acid group-containing diol is used as a raw material, N, N-dimethylethanolamine, N, N-diethylethanolamine, diethanolamine, triethanolamine, triisopropanolamine, trimethylamine, an organic base such as triethylamine, sodium hydroxide, The acid group of the prepolymer is neutralized using a neutralizing agent such as an inorganic base such as potassium hydroxide, ammonia and the like. Preferably, the dispersion stability of the polymer is improved by using a neutralizing agent containing an alkali metal such as sodium hydroxide or potassium hydroxide. The use of these neutralizing agents is preferably 0.5 to 1.0 mol, and more preferably 0.8 to 1.0 mol per mol of the acidic group of the prepolymer, so that viscosity increase hardly occurs and workability is improved. improves.

  Thereafter, the prepolymer is added to a liquid containing a chain extender and a crosslinker to carry out a chain extension reaction and a crosslinking reaction. Then, when an organic solvent is used, it is removed using an evaporator or the like to obtain a dispersion of a polymer.

  As a catalyst used for the polymerization reaction of a polymer, a titanium catalyst, an aluminum catalyst, a zirconium catalyst, an antimony catalyst, a germanium catalyst, a bismuth catalyst and a metal complex catalyst are preferable. Particularly preferred titanium catalysts are tetraalkyl titanates such as tetrabutyl titanate and tetramethyl titanate, and metal salts of oxalate such as titanium potassium oxalate. The other catalyst is not particularly limited as long as it is a known catalyst, and tin compounds such as dibutyltin oxide and dibutyltin dilaurate may be mentioned. As non-heavy metal catalysts, it has long been known that acetylacetonate complexes of transition metals such as titanium, iron, copper, zirconium, nickel, cobalt and manganese have a urethanization activity. In recent years, low toxicity catalysts capable of replacing heavy metal catalysts are desired from the rise of environmental awareness, and high urethanization activity of titanium / zirconium compounds is particularly noted.

(Analysis of macromolecules)
The composition of the polymer, the structure of the polyisocyanate, and the acid value of the polymer can be analyzed by the following methods, respectively.

  First, a method of extracting a polymer from an ink containing a polymer will be described. When the ink jet ink composition contains a pigment, the polymer is extracted from the ink jet ink composition using an organic solvent (acetone, methyl ethyl ketone, etc.) which does not dissolve the pigment but dissolves the polymer. it can. The polymer can also be extracted by fractionating the inkjet ink composition by ultracentrifugation, and acid-outing the supernatant with an acid.

(A) Composition of Polymer A polymer is dissolved in deuterated dimethyl sulfoxide (DMSO-d6) to obtain a sample, and proton nuclear magnetic resonance ( ¹ H-NMR) or carbon 13 nuclear magnetic resonance ( ¹³ C- From the position of the peak obtained by analysis by NMR), types of polyisocyanate, polyol, polyamine and the like can be confirmed. Furthermore, the composition ratio can also be calculated from the ratio of integrated values of chemical shift peaks of each component. Further, even if the polymer is analyzed by pyrolysis gas chromatography (GC-MS), the types of polyisocyanate, polyol, polyamine and the like can be confirmed. Moreover, when analysis is performed by carbon 13 nuclear magnetic resonance spectroscopy ( ¹³ C-NMR), the number of repeating units of long chain polyol unit can be determined to calculate the number average molecular weight.

(B) Structure of Polyisocyanate From the infrared absorption spectrum obtained by analyzing the polymer by Fourier transform infrared spectroscopy (FT-IR), the structure of polyisocyanate can be confirmed. The main absorption is as follows. Allophanate structure, NH stretching vibration absorption at 3300cm ^-1, 1750~1710cm ^-1, and two C = O stretching vibration absorption is present in 1708~1653cm ^-1. Uretdione structure, C = O stretching vibration absorption in 1780~1755cm ^-1, there are absorption based on uretdione ring 1420~1400cm ^-1. Isocyanurate structure, C = O stretching vibration absorption in 1720~1690cm ^-1, there are absorption based on isocyanurate ring 1428~1406cm ^-1. In the biuret structure, C = O stretching vibration absorption is present at 1720 to 1690 cm ⁻¹ .

(C) Acid Value of Polymer The acid value of a polymer can be measured by a titration method. The acid value is measured using AT610 (product name) manufactured by Kyoto Electronics Manufacturing Co. Ltd., and calculated by applying a numerical value to the following formula (1).

Acid value (mg / g) = (EP1-BL1) x FA1 x C1 x K1 / SIZE (1)
(In the above formula, EP1 is the titration volume (mL), BL1 is the blank value (0.0 mL), FA1 is the factor of the titration solution (1.00), C1 is the concentration conversion value (5.611 mg / mL) (0 .1 mo1 / L KOH 1 mL of potassium hydroxide equivalent), K1 represents a coefficient (1), and SIZE represents a sampled amount (g).)

  And an acid value can be measured about the polymer dissolved in tetrahydrofuran by colloid titration using an electrical potential difference. As a titration reagent at this time, an ethanol solution of sodium hydroxide can be used.

1.1.4. Acid Value of Polymer The acid value of the polymer can be measured as described above, but the acid value of the polymer of the present embodiment is preferably 5 mg KOH / g or more and 30 mg KOH / g or less. Further, the acid value of the polymer is more preferably 7 mg KOH / g or more and 25 mg KOH / g or less, still more preferably 8 mg KOH / g or more and 20 mg KOH / g or less. When the acid value is 5 mg KOH / g or more, the dispersion stability in a high molecular weight water-based ink is good, and clogging does not easily occur even at high temperatures. On the other hand, if it is 30 mg KOH / g or less, the polymer is less likely to swell with water, and the ink is less likely to thicken. Furthermore, the water resistance of the recorded matter can be kept good.

The acid value of the polymer can be changed, for example, by adjusting the content of a skeleton derived from a carboxyl group-containing glycol (an acid group-containing polyol such as dimethylol propionic acid). When the inkjet ink composition according to the present embodiment is a water-based ink, it is preferable to use a carboxyl group-containing glycol as a polymer having a carboxyl group so as to be easily dispersed by water.

1.1.5. Polymer Content The inkjet ink composition of the present embodiment may contain a plurality of the above-described polymers. The macromolecule may also be added in the form of an emulsion. The total content of polymers in the inkjet ink composition of the present embodiment is 0.1% or more and 20.0% or less on a mass basis (hereinafter simply referred to as% indicates mass%) as solid content. Is preferably 1.0% to 15.0%.

1.2. Other ingredients 1.2.1. Pigment The inkjet ink composition of the present embodiment may contain a pigment, a dye or the like as a coloring material. The inkjet ink composition of the present embodiment can fix the coloring material physically to the recording medium by the above-described polymer, and therefore, a pigment is more preferable as the coloring material to be used. Such a pigment is attached to a recording medium to form an image (a recorded matter).

  The pigment is not particularly limited, and examples of the pigment type include carbon black, calcium carbonate, inorganic pigments such as titanium oxide, azo pigments, isoindolinone pigments, diketopyrrolopyrrole pigments, phthalocyanine pigments, quinacridone pigments, anthraquinone pigments, etc. Or the like may be used.

  As black pigments, no. 2300, no. 900, MCF 88, no. 33, no. 40, no. 45, no. 52, MA7, MA8, MA100, no. 2200 B, etc. (above, made by Mitsubishi Chemical Corporation), Raven 5750, Raven 5250, Raven 5000, Raven 3500, Raven 1255, Raven 700 etc. (above, Columbia Carbon Co., Ltd.), Rega1 400R, Rega1 330R, Rega1 660R, Mogul L , Monarch 700, Monarch 800, Monarch 880, Monarch 900, Monarch 1000, Monarch 1100, Monarch 1300, Monarch 1400, etc. (above, made by Cabot), Color Black FW1, Color Black FW2, Color Black FW2 V, Color Black FW18, Color Black FW 200, C Examples include lor B1ack S150, Color Black S 160, Color Black S 170, Printex 35, Printex U, Printex V, Printex 140 U, Special Black 6, Special Black 5, Special Black 4 A, Special Black 4 (all manufactured by Degussa), and the like. .

  As the white pigment, C.I. I. Pigment white 1 (basic lead carbonate), 4 (zinc oxide), 5 (a mixture of zinc sulfide and barium sulfate), 6 (titanium oxide), 6: 1 (titanium oxide containing other metal oxides), 7 (Zinc sulfide), 18 (calcium carbonate), 19 (clay), 20 (titanium titanium), 21 (barium sulfate), 22 (natural barium sulfate), 23 (gross white), 24 (alumina white), 25 (gypsum) 26 (magnesium oxide / silicon oxide), 27 (silica), 28 (anhydrous calcium silicate) and the like.

  As yellow pigments, C.I. I. Pigment yellow 1, 2, 3, 4, 5, 6, 7, 10, 11, 12, 13, 14, 16, 17, 24, 34, 35, 53, 55, 65, 73, 74, 75, 81, 83, 93, 94, 95, 97, 98, 99, 108, 109, 110, 113, 114, 117, 120, 124, 128, 129, 133, 138, 139, 147, 151, 154, 154, 154, 167, 172, 180 and the like.

  As the magenta pigment, C.I. I. Pigment red 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 14, 15, 16, 17, 18, 19, 21, 22, 23, 30, 31, 32, 37, 38, 40, 41, 42, 48 (Ca), 48 (Mn), 57 (Ca), 57: 1, 88, 112, 114, 122, 123, 144, 146, 149, 150, 166, 168 170, 171, 175, 176, 177, 178, 179, 184, 185, 187, 202, 209, 219, 224, 245, and C.I. I. Pigment Violet 19, 23, 32, 33, 36, 38, 43, 50 and the like.

  As cyan pigments, C.I. I. Pigment blue 1, 2, 3, 15, 15: 1, 15: 2, 15: 3, 15:34, 15: 4, 16, 18, 22, 25, 60, 65, 66, and C.I. I. Bat Blue 4, 60 and the like.

  Examples of pigments other than black, white, yellow, magenta and cyan include C.I. I. Pigment greens 7, 10, and C.I. I. Pigment browns 3, 5, 25, 26, and C.I. I. Pigment orange 1, 2, 5, 7, 13, 14, 15, 16, 24, 34, 36, 38, 40, 43, 63 and the like.

  The pigment exemplified above is at least one of a pigment (surface treated pigment) in which an anionic group is bonded to the particle surface directly or through another atomic group, and a pigment dispersed with a resin having an anionic functional group. It can be used as

  Examples of the pigment in which an anionic group is bonded to the particle surface directly or through another atomic group include, for example, those obtained by bonding a functional group containing an anionic group to the surface of the pigment particle, and on the surface of the pigment particle What bound anionic resin is mentioned. Further, examples of the pigment dispersed with a resin having an anionic functional group include those obtained by physically adsorbing an anionic resin on the surface of pigment particles, and those obtained by including a pigment by an anionic resin.

Self-dispersing pigment obtained by binding a functional group containing an anionic group on the surface of the pigment _{particles, -COOM, -SO 3 M, -PO} 3 HM, anionic groups such as _-PO 3 _{M 2,} the surface of the pigment particles Directly or through another atomic group. As M, hydrogen atoms, lithium, sodium, potassium, ammonium (NH ₄ ), methylamine, ethylamine, organic amines such as monoethanolamine, diethanolamine, triethanolamine and the like can be mentioned. Further, as another atomic group, a linear or branched alkylene group having 1 to 12 carbon atoms, a phenylene group, a naphthylene group, an amido group, a sulfonyl group, an amino group, a carbonyl group, an ester group, an ether group, and the like And groups in which groups are combined.

  As these self-dispersing pigments, those having an anionic group bonded to the surface of the pigment particle by oxidation treatment according to a known method, and functional groups containing an anionic group such as diazo coupling are bonded to the surface of the pigment particle And all can be suitably used. In a self-dispersible pigment having an anionic resin bonded to the surface of the pigment particle, a resin having at least a unit having an anionic group as a hydrophilic unit is bonded to the surface of the pigment particle directly or through another atomic group. It is

  The resin-dispersed pigment in which the anionic resin is physically adsorbed on the surface of the pigment particle, and the resin-dispersed pigment in which the pigment is contained in the anionic resin are both dispersion methods using a resin dispersant. As the resin dispersant, a copolymer having a hydrophilic group and a hydrophobic group is used.

As a resin dispersant used for a self-dispersion pigment or a resin dispersion pigment, any known resin usable for an ink for ink jet can be used. As a suitable resin dispersant, it is preferable that the hydrophilic group contains at least an anionic group. Examples of hydrophilic groups include those based on hydrophilic monomers such as (meth) acrylic acid and salts thereof. In addition, as the hydrophobic group, functional by hydrophobic monomer such as styrene or a derivative thereof, a monomer having an aromatic ring such as benzyl (meth) acrylate, a monomer having an aliphatic group such as (meth) acrylate, etc. Groups and the like.

  The resin used as the resin dispersant has a weight average molecular weight of from 1,000 to 100,000, further from 3,000 to 80,000, and an acid value of from 50 mg KOH / g to 150 mg KOH / g Is preferred. In the present invention, it is more preferable to use a styrene- (meth) acrylic resin or an (meth) acrylic resin having an acid value of 50 mgKOH / g or more and 150 mgKOH / g or less as a dispersant. When a dispersion method using a dispersant is used, the mass ratio of resin dispersant / pigment is preferably 0.1 times or more and 10.0 times or less, and more preferably 0.5 times or more and 5.0 times or less.

  When the target to which the inkjet ink composition of the present embodiment is attached is a recording medium such as a transparent or translucent film, when using a pigment, using an inorganic pigment (white pigment) provides fixability and abrasion resistance. It is possible to form an excellent underlayer (a first layer described later), and by such an underlayer, it is possible to create a recorded matter with a good background shielding property.

  These exemplified pigments may be used in plural kinds. The total content of the pigment (solid content) in the inkjet ink composition varies depending on the type of pigment used, but from the viewpoint of obtaining good color development, the total mass of the inkjet ink composition is 100% by mass. It is preferable that it is 0.1 to 15.0 mass%, and it is more preferable that it is 1.0 to 10.0 mass%.

  In addition, when preparing to an inkjet ink composition, you may prepare the pigment dispersion liquid which disperse | distributed the pigment beforehand, and may add the pigment dispersion liquid to an inkjet ink composition. As a method of obtaining such a pigment dispersion, a method of dispersing a self-dispersion pigment in a dispersion medium without using a dispersing agent, or dispersing a pigment in a dispersion medium using a polymer dispersant (resin dispersant) There are a method, a method of dispersing the surface-treated pigment in a dispersion medium, and the like.

1.2.2. Water The inkjet ink composition according to the present embodiment may contain water. Examples of water include pure water such as ion exchange water, ultrafiltered water, reverse osmosis water, and distilled water, and water from which ionic impurities have been removed as much as possible, such as ultrapure water. Further, when water sterilized by ultraviolet irradiation, addition of hydrogen peroxide or the like is used, generation of bacteria and fungi can be prevented when the ink jet ink composition is stored for a long time.

  The content of water is 30% by mass or more, preferably 40% by mass or more, more preferably 45% by mass or more, and still more preferably 50% by mass or more based on the total amount of the inkjet ink composition. The term “water in the ink jet ink composition” includes, for example, polymer particle dispersion used as a raw material, pigment dispersion, water added from water to be added, and the like. When the content of water is 30% by mass or more, the inkjet ink composition can have a relatively low viscosity. The upper limit of the water content is preferably 90% by mass or less, more preferably 85% by mass or less, and still more preferably 80% by mass or less, based on the total amount of the inkjet ink composition.

The inkjet ink composition according to the present embodiment is more preferably a water-based ink containing water. As a result, the polymer is easily dispersed in the form of an emulsion, and an image having further excellent fixing properties and abrasion resistance can be easily formed by the ink jet method.

1.2.3. Water-Soluble Organic Solvent The inkjet ink composition of the present embodiment may contain a water-soluble organic solvent. By containing the water-soluble organic solvent, it is possible to effectively suppress the evaporation of water from the recording head after being left for a long period of time, while making the discharge stability of the ink jet ink composition by the ink jet method excellent.

  The water-soluble organic solvent is not particularly limited as long as it is water-soluble, and is a monohydric or polyvalent alcohol, (poly) alkylene glycol, glycol ether, lactam such as ε-caprolactam, 2-pyrrolidone, N-methyl-pyrrolidone, etc. Nitrogen-containing polar solvents such as lactones such as ε-caprolactone and δ-valerolactone, sulfur-containing polar solvents such as dimethylsulfoxide (DMSO), acetin and diacetin can be used. Among them, lactam structure is preferable and 2-pyrrolidone is preferable. The content (% by mass) of the water-soluble organic solvent in the inkjet ink composition is preferably 3.0% by mass or more and 50.0% by mass or less based on the total mass of the ink.

1.2.4. Surfactant The inkjet ink composition of the present embodiment may contain a surfactant. As the surfactant, any of nonionic surfactants, anionic surfactants, cationic surfactants, and amphoteric surfactants can be used, and these may be used in combination.

  When a surfactant is added to the inkjet ink composition, the total amount of surfactants is 0.01% by mass or more and 3% by mass or less, preferably 0.05% by mass or more, based on the entire inkjet ink composition. It is preferable to mix | blend mass% or less, More preferably, it is 0.1 to 1 mass%, Most preferably, it is 0.2 to 0.5 mass%.

  When the ink jet ink composition contains a surfactant, the stability when discharging the ink from the head tends to increase.

1.2.5. Chelating Agent The inkjet ink composition of the present embodiment may contain a chelating agent. Chelating agents have the property of capturing ions. As such a chelating agent, for example, ethylenediamine tetraacetate (EDTA), nitrilotriacetate of ethylenediamine, hexametaphosphate, pyrophosphate or metaphosphate and the like can be mentioned.

1.2.6. Preservative The inkjet ink composition of the present embodiment may contain a preservative. By containing a preservative, the growth of molds and bacteria can be suppressed, and the storage stability of the ink composition becomes better. This makes it easy to use, for example, the inkjet ink composition as a maintenance liquid when maintaining the printer without using it for a long time. Preferred examples of antiseptics include Proxel CRL, Proxel BDN, Proxel GXL, Proxel XL-2, Proxel IB, Proxel TN and the like.

1.2.7. pH adjuster The inkjet ink composition of the present embodiment may contain a pH adjuster. By containing the pH adjusting agent, for example, the elution of impurities from the member forming the ink flow path can be suppressed or promoted, and the cleaning property of the inkjet ink composition can be adjusted. Examples of pH adjusters include morpholines, piperazines, and amino alcohols such as triethanolamine.

1.2.8. Other Components The inkjet ink composition according to the present embodiment may, if necessary, be solid at room temperature, such as polyhydric alcohols such as trimethylolpropane and trimethylolethane, and urea derivatives such as urea and ethylene urea. It may contain a water soluble organic compound. Furthermore, various additives such as a rust inhibitor, a mildew inhibitor, an antioxidant, a reduction inhibitor, an evaporation promoter and a water-soluble resin may be contained as needed.

1.3. Method of Producing Ink Jet Ink Composition The method of producing the ink jet ink composition of the present embodiment is not particularly limited, and can be produced, for example, as follows.

  First, when polymerizing a polymer, the reaction is carried out in a solvent containing 2-pyrrolidone to give dicyclohexylmethane diisocyanate, isophorone diisocyanate, 1,3-bis (isocyanatomethyl) cyclohexane, m-bis (isocyanate propyl) benzene and m And-forming a polymer having a urethane group or a urea group derived from one or more selected from bis (isocyanatomethyl) benzene.

  And it can manufacture by mixing the obtained polymer dispersion or polymer solution, and each above-mentioned component in arbitrary order, filtering etc. and removing an impurity as needed. As a mixing method of each component, a method of sequentially adding materials to a container equipped with a stirring device such as a mechanical stirrer, a magnetic stirrer, etc. and stirring and mixing is suitably used.

  When manufactured in this manner, 2-pyrrolidone can be left to be used as a component of the ink jet ink composition, so that the solvent can be effectively used, and in addition to using a solvent having a standard boiling point of 100 ° C. or less, For example, when the ink-jet ink composition is attached to a recording medium such as a film, it is easy to obtain an image with excellent gloss.

1.4. Physical Properties of the Ink Jet Ink Composition <Tension>
The inkjet ink composition according to the present embodiment preferably has a surface tension of 20 mN / m or more and 40 mN / m, preferably 20 mN, from the viewpoint of the balance between image quality and reliability as an ink for ink jet recording. It is more preferable that it is / m or more and 35 mN / m or less. The surface tension is measured, for example, when the platinum plate is wetted with an ink at 20 ° C. using an automatic surface tension meter CBVP-Z (trade name, manufactured by Kyowa Interface Science Co., Ltd.). It can measure by confirming.

<Viscosity>
Further, from the same viewpoint, the viscosity at 20 ° C. of the inkjet ink composition according to the present embodiment is preferably 3 mPa · s or more and 10 mPa · s or less, and more preferably 3 mPa · s or more and 8 mPa · s or less preferable. In addition, the measurement of viscosity can be performed under an environment of 20 ° C. using, for example, a viscoelasticity tester MCR-300 (trade name, manufactured by Pysica).

1.5. Effect, etc. According to the inkjet ink composition of the present embodiment, by adding the above-described polymer, the scratch resistance of an image to be recorded can be improved, and clogging and intermittent discharge stability can be maintained high. . The intermittent discharge stability is related to the acid value of the polymer, and when the acid value is high, the hydrophilicity of the polymer is enhanced and the intermittent discharge stability is improved. However, when the acid value of the polymer is too high, although the intermittent discharge stability is improved, the scratch resistance and water resistance of the recorded image tend to be lowered. In addition, it is also known that the intermittent discharge stability of the ink is lowered depending on the form in which the polymer is contained in the inkjet ink composition.

  In general, the reduction in intermittent discharge stability is caused by the evaporation of water from the nozzle of the ink jet head. In order to enhance intermittent discharge stability, the pigment and resin do not aggregate even when water interacts to some extent from the ink present in the vicinity of the nozzle of the inkjet head and the interaction between the polymer and the pigment is strengthened. It is necessary to maintain a stably dispersed state.

  Although the polymer contained in the ink jet ink composition of the present embodiment has a relatively low acid value, it has a sterically complicated complex entangled structure, so even if the evaporation of water proceeds, the polymer and the pigment are separated. It is easy to cause repulsion by electrostatic action and repulsive force. As a result, in the inkjet ink composition of the present embodiment, the abrasion resistance of the recorded matter is improved, and the dispersed state of the pigment is stably maintained, so that the clogging stability and the intermittent discharge stability can be improved.

  Furthermore, as in the case of the polymer contained in the inkjet ink composition of the present embodiment, by appropriately blending the isocyanate, the glossiness when applied to a highly flat recording medium such as a film is improved.

  Since the polymer is mainly composed of polyisocyanate and a component that reacts with it, short-chain polyols such as acid group-containing diols when increasing the acid value of the polymer to improve the intermittent discharge stability of the inkjet ink composition Will increase the proportion of Then, as with the short chain polyol, the proportion occupied by the long chain polyol, which is the component to be reacted with the polyisocyanate, decreases. In this case, the increase in urethane bonds and the decrease in soft segments in the polymer impair the flexibility of the polymer film. Therefore, when the hydrophilicity is increased by increasing the acid value of the polymer, the intermittent discharge stability of the ink jet ink composition is improved, but the abrasion resistance and the water resistance of the image are reduced.

  The polymer contained in the ink jet ink composition of the present embodiment is not a method of enhancing the hydrophilicity of the polymer by raising the acid number, but the acid number is lowered to a certain extent as 5 to 30 mg KOH / g to make the ink jet ink composition. The intermittent discharge stability of the thing is secured. Then, the abrasion resistance of the image is improved by polymerizing the polymer using a raw material containing a specific diisocyanate, and sufficient glossiness is obtained even when it is used for a recording medium such as a film which is required to have glossiness. Is supposed to be obtained.

2. Recording method 2.1. Recording Medium The recording method according to the present embodiment is used in a recording method for recording on a recording medium using an inkjet ink composition. Hereinafter, an example of a recording medium used together with the recording method according to the present embodiment will be described.

The recording medium used in the recording method of the present embodiment is not particularly limited, but a low absorption or non-absorbing recording medium is preferable. A low absorbing or non-absorbing recording medium refers to a recording medium that has the property of not absorbing at all or hardly absorbing ink. Quantitatively, the recording medium used in the present embodiment refers to "a recording medium having a water absorption of up to 30 msec ^1/2 in the Bristow method at 10 mL / m ² or less." The Bristow method is most widely used as a method for measuring the amount of liquid absorbed in a short time, and is also adopted by the Japan Paper and Pulp Technical Association (JAPAN TAPPI). For the details of the test method, the standard No. 1 of "JAPAN TAPPI Paper Pulp Test Method 2000 Edition". 51 "Paper and board-liquid absorption test method-Bristow method". Examples of recording media having such non-absorptive properties include recording media that do not have an ink receiving layer with ink absorbability on the recording surface, and recording media that have a coating layer with small ink absorbability on the recording surface. .

  The non-absorptive recording medium is not particularly limited. For example, a plastic film not having an ink absorbing layer, a substrate in which a plastic is coated on a substrate such as paper, a medium in which a plastic film is adhered, etc. Can be mentioned. Examples of the plastic herein include polyvinyl chloride, polyethylene terephthalate, polycarbonate, polystyrene, polyurethane, polyethylene, polypropylene and the like.

  The low absorption recording medium is not particularly limited, and examples thereof include a coated paper provided with a coating layer for receiving an oil-based ink on the surface. The coated paper is not particularly limited, and examples thereof include printing papers such as art paper, coated paper, and matte paper.

  By using the ink jet ink composition of the present embodiment, it is possible to easily make a predetermined image having good fixability and good scratch resistance even for such non-ink-absorbing or low-ink-absorbing recording media. It can be formed.

  In the recording method according to the present embodiment, it is more preferable that the recording medium to be attached has polyolefin (polyethylene, polypropylene or the like) as a main component. Such a recording medium is generally a recording medium in which adhesion is difficult, and an image having good fixability and abrasion resistance can be formed, so that the fixability and abrasion resistance are good. The effect of being present is even more remarkable.

2.2. Recording Method The recording method according to the present embodiment uses the above-described inkjet ink composition. According to such a recording method, for example, when an ink jet ink composition is discharged from an ink jet head on a recording medium to form an image layer, intermittent discharge stability is ensured, and the fixability and abrasion resistance of an image are secured. It is possible to obtain an image that is compatible with sex.

  The recording method of the present embodiment is a method of recording an image on a recording medium by discharging the inkjet ink composition of the present embodiment described above from an inkjet recording head. Examples of the method of ejecting the ink include a method of applying mechanical energy to the ink by the electrostrictive element and a method of applying thermal energy to the ink. In the present embodiment, it is particularly preferable to use a method of applying mechanical energy to the ink by an electrostrictive element.

3. Examples and Comparative Examples Hereinafter, the present invention will be described in more detail by way of examples and comparative examples, but various modifications are possible without departing from the scope of the present invention, and the present invention is not limited by the following examples. It is not something to be done. In addition, what is described as% regarding component amount is mass% unless otherwise indicated.

3.1. Polymer Polymerization <Preparation of Urethane Resin Emulsion A1>
In a reaction vessel into which a stirrer, a reflux condenser and a thermometer were inserted, polycarbonate diol a (PCDa: reaction product of 1,6-hexanediol and dimethyl carbonate, number average molecular weight 2000) 1500 g, 2,2-dimethylol propionic acid 220 g of (DMPA) and 1347 g of 2-pyrrolidone (2-P: bp 245 ° C.) were charged under a nitrogen stream, and heated to 60 ° C. to dissolve DMPA. 1,300 g of 4,4'-dicyclohexylmethane diisocyanate (MCHDI) and 2.6 g of a urethane forming catalyst XK-614 (manufactured by Kushimoto Chemical Co., Ltd.) are added and heated to 90 ° C. to perform a urethane forming reaction over 5 hours, A polymer was obtained.

  Then, the reaction mixture was cooled to 80 ° C., 4340 g of which was added and mixed with 220 g of triethanolamine was added to a mixed solution of 5400 g of water and 22 g of triethanolamine under strong stirring. Next, 1500 g of ice is added, 1084 g of 35% by weight of bicycloheptanedimethanamine aqueous solution is added, chain extension reaction is carried out, the solvent is distilled off so that the solid concentration becomes 30%, polycarbonate urethane resin emulsion A1 ( 30% of urethane resin component, 64% of water, 6% of 2-pyrrolidone, and an acid value of 18 mg KOH / g) were obtained.

<Preparation of Urethane Resin Emulsion A2>
In the preparation of the urethane resin emulsion A1, 1100 g of isophorone diisocyanate (IPDI) is used instead of 1300 g of 4,4'-dicyclohexylmethane diisocyanate (MCHDI), and 2250 g of polycarbonate diol b (PCDb) instead of 1500 g of polycarbonate diol a (PCDa) A polycarbonate-based urethane resin emulsion A2 (30% urethane resin component, 64% water, 6% 2-pyrrolidone, and an acid value of 18 mg KOH / g) was similarly obtained except that it was used.

Preparation of Urethane Resin Emulsion A3
A polycarbonate-based urethane resin emulsion A3 (urethane) was similarly prepared except that 950 g of 1,3-bis (isocyanatomethyl) cyclohexane (BIMCH) was used instead of 1300 g of 4,4′-dicyclohexylmethane diisocyanate in the production of the urethane resin emulsion A1. 30% resin component, 64% water, 6% 2-pyrrolidone, and an acid value of 18 mg KOH / g) were obtained.

Preparation of Urethane Resin Emulsion A4
A polycarbonate-based urethane resin emulsion A4 (A4 (A)) was prepared in the same manner as in the preparation of the urethane resin emulsion A2, except that 1070 g of m-bis (isocyanatopropyl) benzene (BIPB) was used instead of 1300 g of 30% of urethane resin component, 64% of water, 6% of 2-pyrrolidone, and an acid value of 18 mg KOH / g) were obtained.

<Preparation of Urethane Resin Emulsion A5>
A polycarbonate-based urethane resin emulsion A5 (a polyurethane resin emulsion A5) was prepared in the same manner as in the preparation of the urethane resin emulsion A1, except that 930 g of m-bis (isocyanatomethyl) benzene (BIMB) was used instead of 1300 g of 4,4′-dicyclohexylmethane diisocyanate (MCHDI). 30% of urethane resin component, 64% of water, 6% of 2-pyrrolidone, and an acid value of 18 mg KOH / g) were obtained.

<Preparation of Urethane Resin Emulsion A6>
In the production of the urethane resin emulsion A1, instead of 1300 g of 4,4'-dicyclohexylmethane diisocyanate (MCHDI), 1400 g of polyisocyanate A (PICA) shown below is used, and polycarbonate diol b (PCDa) is used instead of 1500 g of polycarbonate diol a (PCDa) A polycarbonate-based urethane resin emulsion A6 (30% urethane resin component, 64% water, 6% 2-pyrrolidone, and an acid value of 18 mg KOH / g) was similarly obtained except that PCDb 2250 g was used.

Preparation of Urethane Resin Emulsion A7
Polycarbonate-based urethane resin emulsion A7 (urethane resin) in the same manner as in preparation of urethane resin emulsion A1, except that 1020 g of polyisocyanate B (PICB) shown below was used instead of 1300 g of 4,4′-dicyclohexylmethane diisocyanate (MCHDI) 30% of components, 64% of water, 6% of 2-pyrrolidone, and an acid value of 18 mg KOH / g) were obtained.

<Preparation of Urethane Resin Emulsion A8>
Polycarbonate-based urethane resin emulsion A8 (urethane resin component 30) in the same manner as in production of urethane resin emulsion A3, except that 1500 g of polycarbonate diol a (PCDa) was changed to 1500 g of polycarbonate diol b (PCDb) and 500 g of polycarbonate diol c (PCDc). %, Water 64%, 2-pyrrolidone 6%, acid value 18 mg KOH / g).

<Preparation of Urethane Resin Emulsion A9>
Polycarbonate-based urethane resin emulsion A9 (urethane resin component 30) in the same manner as in production of urethane resin emulsion A4, except that 1500 g of polycarbonate diol a (PCDa) was changed to 1500 g of polycarbonate diol b (PCDb) and 500 g of polycarbonate diol c (PCDc). %, Water 64%, 2-pyrrolidone 6%, acid value 18 mg KOH / g).

<Preparation of Urethane Resin Emulsion A10>
Polycarbonate-based urethane resin emulsion A10 (urethane resin component 30) in the same manner as in the preparation of the urethane resin emulsion A2, except that it was changed to 930 g of 1,3-bis (isocyanatomethyl) cyclohexane (BIMCH) instead of 1100 g of isophorone diisocyanate (IPDI). %, Water 64%, 2-pyrrolidone 6%, acid value 18 mg KOH / g).

<Preparation of Urethane Resin Emulsion A11>
Polycarbonate-based urethane resin emulsion A11 (urethane resin) in the same manner as in the production of the urethane resin emulsion A10, except that the polycarbonate diol b (PCDb) was changed to 2100 g and the trimethylolpropane (TMP) 5 g instead of 2250 g. 30% of components, 64% of water, 6% of 2-pyrrolidone, and an acid value of 18 mg KOH / g) were obtained.

Preparation of Urethane Resin Emulsion A12
Polycarbonate-based urethane resin emulsion A12 (urethane resin) in the same manner as in the production of the urethane resin emulsion A11 except that 2050 g of polycarbonate diol b (PCDb) and 10 g of triethylene glycol (TEG) were used instead of 2250 g of polycarbonate diol b (PCDb) 30% of components, 64% of water, 6% of 2-pyrrolidone, and an acid value of 18 mg KOH / g) were obtained.

<Preparation of Urethane Resin Emulsion A13>
Polycarbonate-based urethane resin emulsion A13 (urethane resin) in the same manner as in production of resin emulsion A5, except that 990 g of 2,4-tolylene diisocyanate (TDI) was used instead of 930 g of m-bis (isocyanatomethyl) benzene (BIMB) 30% of components, 64% of water, 6% of 2-pyrrolidone, and an acid value of 18 mg KOH / g) were obtained.

Preparation of Urethane Resin Emulsion A14
Polycarbonate-based urethane resin emulsion A14 (urethane resin) in the same manner as in the production of resin emulsion A5, except that 1420 g of 4,4′-diphenylmethane diisocyanate (MDI) was used instead of 930 g of m-bis (isocyanate methyl) benzene (BIMB) 30% of components, 64% of water, 6% of 2-pyrrolidone, and an acid value of 18 mg KOH / g) were obtained.

<Preparation of Urethane Resin Emulsion A15>
Polycarbonate-based urethane resin emulsion A15 (urethane resin) in the same manner as in production of resin emulsion A5, except that 960 g of 1,6-hexamethylene diisocyanate (HDI) was used instead of 930 g of m-bis (isocyanate methyl) benzene (BIMB) 30% of components, 64% of water, 6% of 2-pyrrolidone, and an acid value of 18 mg KOH / g) were obtained.

<Preparation of Urethane Resin Emulsion A16>
In preparation of resin emulsion A5, except that 880 g of 4,4'-diphenylmethane diisocyanate (MDI) and 370 g of 1,6-hexamethylene diisocyanate (HDI) were used instead of 930 g of m-bis (isocyanatomethyl) benzene (BIMB) Similarly, polycarbonate-based urethane resin emulsion A16 (urethane resin component 30%, water 64%, 2-pyrrolidone 6%, acid value 18 mg KOH / g) was obtained.

<Preparation of Urethane Resin Emulsion A17>
Polycarbonate-based urethane resin emulsion A17 (urethane resin) except that in the production of resin emulsion A5, 50 g of 2,2-dimethylol propionic acid (DMPA) was used instead of 220 g of 2,2-dimethylol propionic acid (DMPA) Component 30%, water 64%, 2-pyrrolidone 6%, acid value 4 mg KOH / g) were obtained.

<Preparation of Urethane Resin Emulsion A18>
Polycarbonate-based urethane resin emulsion A18 (urethane resin) in the same manner as in production of resin emulsion A5, except that 390 g of 2,2-dimethylol propionic acid (DMPA) was used instead of 220 g of 2,2-dimethylol propionic acid (DMPA) The component was 30%, water 64%, 2-pyrrolidone 6%, and acid value 32 mg KOH / g).

<Preparation of Urethane Resin Emulsion B1>
Polyether-based urethane resin emulsion B1 (urethane resin component 30) in the same manner except that polyoxypropylene glycol (PPG 2000: number average molecular weight 2000) was used instead of 1500 g of polycarbonate diol a (PCDa) in the production of urethane resin emulsion A3. %, Water 64%, 2-pyrrolidone 6%, acid value 18 mg KOH / g).

<Preparation of Urethane Resin Emulsion B2>
Polyether-based urethane resin emulsion B2 (urethane resin component) in the same manner as in the production of the urethane resin emulsion A4, except that 2250 g of polyoxypropylene glycol (PPG3000: number average molecular weight 3000) was used instead of 1500 g of polycarbonate diol a (PCDa) 30%, water 64%, 2-pyrrolidone 6%, acid value 18 mg KOH / g) were obtained.

<Preparation of Urethane Resin Emulsion B3>
A polyether was prepared in the same manner as in the preparation of the urethane resin emulsion A4, except that 1000 g of polyoxypropylene glycol (PPG 2000: number average molecular weight 2000) and 500 g of polycarbonate diol a (PCDa) were used instead of 1500 g of polycarbonate diol a (PCDa). Polycarbonate-based urethane resin emulsion B3 (urethane resin component 30%, water 64%, 2-pyrrolidone 6%, acid value 18 mg KOH / g) was obtained.

<Preparation of Urethane Resin Emulsion B4>
A polyurethane resin emulsion B2 was prepared in the same manner except that 2250 g of polyoxypropylene glycol (PPG3000: number average molecular weight 3000) and 2100 g of polyoxypropylene glycol (PPG 3000: number average molecular weight 3000) and 5 g of trimethylolpropane (TMP) were used. Thus, a polyether-based urethane resin emulsion B4 (urethane resin component 30%, water 64%, 2-pyrrolidone 6%, acid value 18 mg KOH / g) was obtained.

<Preparation of Urethane Resin Emulsion B5>
Polyether-based urethane resin emulsion B5 (urethane resin component) in the same manner as in the production of the urethane resin emulsion A4, except that 375 g of polyoxypropylene glycol (PPG 500: number average molecular weight 500) was used instead of polycarbonate diol a (PCDa) 1500 g. 30%, water 64%, 2-pyrrolidone 6%, acid value 18 mg KOH / g) were obtained.

Preparation of Urethane Resin Emulsion B6
Polyether-based urethane resin emulsion B6 (urethane resin component) in the same manner as in the production of the urethane resin emulsion A4, except that 300 g of polyoxypropylene glycol (PPG 400: number average molecular weight 400) was used instead of 1500 g of polycarbonate diol a (PCDa) 30%, water 64%, 2-pyrrolidone 6%, acid value 18 mg KOH / g) were obtained.

<Preparation of Urethane Resin Emulsion B7>
Polyether-based urethane resin emulsion B7 (urethane resin component) in the same manner as in the production of the urethane resin emulsion A4, except that 3000 g of polyoxypropylene glycol (PPG4000: weight average molecular weight 4000) was used instead of 1500 g of polycarbonate diol a (PCDa) 30%, water 64%, 2-pyrrolidone 6%, acid value 18 mg KOH / g) were obtained.

<Preparation of Urethane Resin Emulsion B8>
Polyether-based urethane resin emulsion B8 (urethane resin component) in the same manner as in the production of the urethane resin emulsion A4, except that 1500 g of polyoxyethylene glycol (PEG 2000: weight average molecular weight 2000) was used instead of 1500 g of polycarbonate diol a (PCDa) 30%, water 64%, 2-pyrrolidone 6%, acid value 18 mg KOH / g) were obtained.
<Preparation of Urethane Resin Emulsion B9>
Polyether-based urethane resin emulsion B9 (30% urethane resin component, 64% water) in the same manner as in the production of the urethane resin emulsion A4, except that 1500 g of the polycarbonate diol d (PCDd) was used instead of 1500 g of the polycarbonate diol a (PCDa) , 2-pyrrolidone, and an acid value of 18 mg KOH / g).
Preparation of Urethane Resin Emulsion B10
Polyether-based urethane resin emulsion B10 (30% urethane resin component, 64% water) in the same manner as in the preparation of the urethane resin emulsion A4, except that 1500 g of polycarbonate diol e (PCDe) was used instead of 1500 g of polycarbonate diol a (PCDa) , 2-pyrrolidone, and an acid value of 18 mg KOH / g).

<Preparation of Urethane Resin Emulsion C1>
In the preparation of A5 of the urethane resin emulsion, 1347 g of methyl ethyl ketone (MEK: bp 79.6 ° C.) is used instead of 1347 g of 2-pyrrolidone (2-P: bp 245 ° C.), and the solvent is distilled so that the solid concentration becomes 30%. It removed and obtained polycarbonate-type urethane resin emulsion C1 (30% of urethane resin component, water 70%, acid value 18 mgKOH / g).

<Preparation of Urethane Resin Emulsion C2>
In the preparation of A6 of the urethane resin emulsion, 1347 g of methyl ethyl ketone (MEK: bp 79.6 ° C.) is used instead of 1347 g of 2-pyrrolidone (2-P: bp 245 ° C.), and the solvent is distilled so that the solid concentration becomes 30%. It removed and obtained polycarbonate-type urethane resin emulsion C2 (30% of urethane resin component, 70% of water, an acid value of 18 mg KOH / g).

<Preparation of Urethane Resin Emulsion C3>
In production of A7 of the urethane resin emulsion, 1347 g of methyl ethyl ketone (MEK: bp 79.6 ° C.) is used instead of 1347 g of 2-pyrrolidone (2-P: bp 245 ° C.), and the solvent is distilled so that the solid concentration becomes 30%. It removed and obtained polycarbonate-type urethane resin emulsion C3 (30% of urethane resin component, water 70%, acid value 18 mgKOH / g).

<Preparation of Urethane Resin Emulsion C4>
In the preparation of A8 of the urethane resin emulsion, 1347 g of methyl ethyl ketone (MEK: bp 79.6 ° C.) is used instead of 1347 g of 2-pyrrolidone (2-P: bp 245 ° C.), and the solvent is distilled so that the solid concentration becomes 30%. It removed and obtained polycarbonate-type urethane resin emulsion C4 (30% of urethane resin component, 70% of water, an acid value of 18 mgKOH / g).

<Preparation of Urethane Resin Emulsion C5>
In the preparation of A9 of the urethane resin emulsion, 1347 g of methyl ethyl ketone (MEK: bp 79.6 ° C.) is used instead of 1347 g of 2-pyrrolidone (2-P: bp 245 ° C.), and the solvent is distilled so that the solid concentration becomes 30%. It removed and obtained polycarbonate-type urethane resin emulsion C5 (30% of urethane resin component, water 70%, acid value 18 mgKOH / g).

<Preparation of Urethane Resin Emulsion C6>
In the preparation of the urethane resin emulsion A11, 1347 g of methyl ethyl ketone (MEK: bp 79.6 ° C.) is used instead of 1347 g of 2-pyrrolidone (2-P: bp 245 ° C.), and the solvent is distilled so that the solid concentration becomes 30%. It removed and obtained polycarbonate-type urethane resin emulsion C6 (30% of urethane resin component, 70% of water, acid value of 18 mg KOH / g).

<Preparation of Urethane Resin Emulsion C7>
In production of A13 of the urethane resin emulsion, 1347 g of methyl ethyl ketone (MEK: bp 79.6 ° C.) is used instead of 1347 g of 2-pyrrolidone (2-P: bp 245 ° C.), and the solvent is distilled so that the solid concentration becomes 30%. It removed and obtained polycarbonate-type urethane resin emulsion C7 (30% of urethane resin component, water 70%, acid value 18 mgKOH / g).

<Preparation of Urethane Resin Emulsion C8>
In production of A16 of the urethane resin emulsion, 1347 g of methyl ethyl ketone (MEK: bp 79.6 ° C.) is used instead of 1347 g of 2-pyrrolidone (2-P: bp 245 ° C.), and the solvent is distilled so that the solid concentration becomes 30%. It removed and obtained polycarbonate-type urethane resin emulsion C8 (30% of urethane resin component, water 70%, acid value 18 mgKOH / g).
<Preparation of Urethane Resin Emulsion C9>
Polycarbonate-based urethane resin emulsion C9 (urethane resin) similarly to the preparation of C1 of the urethane resin emulsion, wherein 61 g of 2,2-dimethylol propionic acid (DMPA) is substituted for 220 g of 2,2-dimethylol propionic acid (DMPA) The component was 30%, water 64%, 2-pyrrolidone 6%, and acid value 5 mg KOH / g).
<Preparation of Urethane Resin Emulsion C10>
Polycarbonate-based urethane resin emulsion C10 (urethane resin) similarly to the production of urethane resin emulsion C1 in which 2,3 dimethyl dimethyl propionic acid (DMPA) was replaced by 367 g instead of 2,2 dimethyl dimethyl propionic acid (DMPA) Component 30%, water 64%, 2-pyrrolidone 6%, acid value 30 mg KOH / g) was obtained.

  The above urethane resin emulsions A to C are summarized in the following Tables 1 to 3.

3.2. Production of Urethane Resin Raw Material <Production of Polycarbonate Diol a (PCDa)>
In a 1-L glass separable flask equipped with a stirrer, distillate trap, and pressure regulator, 123 g of 1,6-hexanediol (1,6-HD), 203 g of diphenyl carbonate, 203 magnesium acetate water as a raw material Hydrate: 4.4 mg was added and replaced with nitrogen gas. Under stirring, the internal temperature was raised to 160 ° C. to 170 ° C. to heat and dissolve the contents. Then, after reducing the pressure from atmospheric pressure to 26 kPa, the reaction was carried out for 100 minutes while removing the by-product phenol out of the system. Next, the pressure is decreased to 0.6 kPa and the reaction is continued, and then the temperature is raised to 180 ° C. to react for 100 minutes while removing by-product phenol and unreacted dihydroxy compound out of the system, polycarbonate diol a (PCDa ) Containing composition. It was 2000 when the number average molecular weight of styrene conversion was measured using THF as a solvent and using gel permeation chromatography (GPC) of Hitachi L7100 system manufactured by Hitachi, Ltd.

<Production of Polycarbonate Diol b (PCDb)>
1,5-pentanediol (1,5-PD): 63 g, 1,8-octanediol (1,8) as a raw material, using the same apparatus as that used for the production of polycarbonate diol a
-OD): 60 g, diphenyl carbonate: 203 g, magnesium acetate tetrahydrate: 4.4 mg were charged, and nitrogen gas substitution was carried out. Under stirring, the internal temperature was raised to 160 ° C. to 170 ° C. to heat and dissolve the contents. Then, after reducing the pressure from atmospheric pressure to 26 kPa, the reaction was carried out for 100 minutes while removing the by-product phenol out of the system. Next, the pressure is lowered to 0.6 kPa and the reaction is continued, and then the temperature is raised to 180 ° C. to react for 100 minutes while removing by-product phenol and unreacted dihydroxy compound out of the system, polycarbonate diol b (PCDb ) Containing composition. It was 3000 when the number average molecular weight of styrene conversion was measured.

<Production of Polycarbonate Diol c (PCDc)>
A polycarbonate diol c (PCDc) -containing composition was obtained in the same manner except that 123 g of 1,6-hexanediol was changed to 1,4-cyclohexanediol in the production of polycarbonate diol a. It was 2000 when the number average molecular weight of styrene conversion was measured.

<Production of Polycarbonate Diol d (PCD d)>
A composition containing polycarbonate diol d (PCDd) was obtained in the same manner as in the preparation of polycarbonate diol a except that 4.4 mg of magnesium acetate tetrahydrate was changed to 9 mg and the reaction time was changed to 30 minutes. It was 450 when the number average molecular weight of styrene conversion was measured.

<Production of Polycarbonate Diol e (PCDe)>
A polycarbonate diol e (PCDe) -containing composition e was obtained in the same manner as in the preparation of polycarbonate diol a except that the reaction temperature was changed from 160 ° C. to 170 ° C. to 140 ° C. to 150 ° C. and the reaction time was changed to 300 minutes. It was 3500 when the number average molecular weight of styrene conversion was measured.

<Synthesis of Polyisocyanate A (PICA)>
In a reactor equipped with a stirrer, a thermometer, a cooler, and a nitrogen gas inlet tube, under nitrogen atmosphere, 186.0 parts of 4,4'-dicyclohexylmethane diisocyanate, 14.0 parts of isopropyl alcohol, and 0. One part of dibutyltin oxide was added, and the mixture was reacted at a temperature of 80 ° C. for 2 hours to perform urethanization to obtain a reaction solution. To the resulting reaction solution, 0.01 part of zirconium 2-ethylhexanoate (allophanation catalyst) was added and reacted at a temperature of 110 ° C. to obtain a reaction solution. Unreacted 4,4'-dicyclohexylmethane diisocyanate was removed by distilling the obtained reaction liquid using a thin-film distillation apparatus to obtain polyisocyanate A (PICA). The isocyanate group content was adjusted to 20.0%.

<Synthesis of Polyisocyanate B (PICB)>
In a reactor equipped with a stirrer, thermometer, condenser and nitrogen gas inlet, 186.0 parts of hydrogenated xylylene diisocyanate, 14.0 parts of isopropyl alcohol, and 0.1 part under a nitrogen atmosphere Dibutyltin oxide was added, and reaction was carried out at a temperature of 80 ° C. for 2 hours to perform urethanization to obtain a reaction solution. To the resulting reaction solution, 0.01 part of zirconium 2-ethylhexanoate (allophanation catalyst) was added and reacted at a temperature of 110 ° C. to obtain a reaction solution. The unreacted hydrogenated xylylene diisocyanate was removed by distilling the obtained reaction liquid using a thin-film distillation apparatus to obtain polyisocyanate B (PICB). The isocyanate group content was adjusted to 20.0%.

3.3. Preparation of pigment dispersion (pigment dispersion 1)
500 g of deionized water and 15 g of carbon black were mixed and stirred for 30 minutes using a rocking mill using 1 mm zirconia beads to prewet the pigment. To this was added 4485 g of ion exchanged water and dispersed by a high pressure homogenizer. The average particle size of the pigment at this time was 110 nm. The pigment was transferred to a high pressure vessel and pressurized at a pressure of 3 MPa, and then the surface of the pigment was subjected to ozone oxidation treatment by introducing ozone water having an ozone concentration of 100 ppm. Thereafter, the pH of this dispersion was adjusted to 9.0 using a 0.1 mol / L aqueous sodium hydroxide solution, and then the concentration of the pigment solid content was adjusted to obtain pigment dispersion 1. The pigment dispersion liquid 1 contains a self-dispersion pigment in which —COONa group is bonded to the particle surface, and the content of the pigment is 30%.

(Pigment dispersion 2)
500 g of carbon black, 1000 g of a water-soluble resin, and 14000 g of water were mixed to obtain a mixture. As the water-soluble resin, one obtained by neutralizing a styrene-acrylic acid copolymer having an acid value of 100 mg KOH / g and a weight average molecular weight of 10,000 with a 0.1 mol / L sodium hydroxide aqueous solution was used. After dispersing this mixture for 1 hour using a rocking mill using 1 mm zirconia beads, impurities were removed by centrifugation, and vacuum filtration was performed using a microfilter (manufactured by Millipore) with a pore size of 5.0 μm. Next, the pigment solid content was adjusted to obtain a pigment dispersion 2 having a pH of 9.0. The pigment dispersion liquid 2 contained a pigment dispersed by a water-soluble resin (resin dispersant), the content of the pigment was 30.0%, and the content of the resin was 15.0%.

(Pigment dispersion 3)
A reaction vessel equipped with a stirrer, thermometer, reflux tube and dropping funnel is purged with nitrogen, and then 300 parts by mass of methyl ethyl ketone is charged, 40 parts by mass of styrene, 40 parts by mass of ethyl methacrylate, 5 parts by mass of lauryl acrylate, 5 parts by mass of lauryl methacrylate Add 5 parts by mass of methoxy polyethylene glycol 400 acrylate AM-90G (manufactured by Shin-Nakamura Chemical Co., Ltd.), 5 parts by mass of acrylic acid, 0.2 parts by mass of ammonium persulfate, 0.3 parts by mass of t-dodecyl mercaptan in a dropping funnel The polymer dispersant was allowed to polymerize while dropping into the reaction vessel over 4 hours. Thereafter, methyl ethyl ketone was added to the reaction vessel to prepare a 40% by mass polymer dispersant solution.

  It was 58000 when the solvent was made into THF and the weight average molecular weight of styrene conversion was measured about the said polymer dispersant solution using the gel permeation chromatography (GPC) of Hitachi Ltd. L7100 system. Moreover, the value of polydispersity (Mw / Mn) was 3.1.

Further, 40 parts by mass of the above-mentioned polymer dispersant solution and Chromofine Blue C.I. I. Pigment Blue 15: 3 (manufactured by Dainichi Seika Kogyo Co., Ltd., trade name, hereinafter also referred to as “PB 15: 3”) 30 parts by mass, 0.1 parts by mass of a 0.1 mol / L aqueous solution of sodium hydroxide and 30 parts by mass of methyl ethyl ketone Then, 8-pass dispersion processing was performed with Ultimizer 25005 (product name of Sugino Machine Co., Ltd.). Thereafter, 300 parts by mass of ion exchange water was added, and the whole amount of methyl ethyl ketone and a part of water were distilled off using a rotary evaporator, and the mixture was adjusted to pH 9 by neutralization with 0.1 mol / L sodium hydroxide. . Then, while measuring the volume average particle size of the cyan pigment with a particle size distribution analyzer, disperse until the volume average particle size becomes 100 nm, filter with a 3 μm membrane filter, and solid content (polymer dispersant and pigment) 20 mass % Pigment dispersion was obtained.

3.4. Preparation of Inkjet Ink Composition <Preparation of Ink>
(Examples 1 to 40, Comparative Examples 1 to 12)
The components shown below were mixed and sufficiently stirred, and then vacuum filtration was performed using a microfilter (manufactured by Millipore) with a pore size of 5.0 μm to prepare inkjet ink compositions of the examples and the comparative examples. The compositions of the ink jet ink compositions of Examples and Comparative Examples are shown in Tables 4 to 6. Tables 4 to 6 show net addition amounts of pigment solids. Tables 4 to 6 show the amount of 2-pyrrolidone contained in the inkjet ink composition.

  As components other than those shown in Tables 4 to 6, 2% of 1,2-hexanediol (1,2-HD), 10% of propylene glycol (PG), and 0.5% of triethanolamine (TEA), 0.02% of EDTA (ethylenediaminetetraacetic acid 2Na salt), 0.5% of Orphin PD 501 (nonionic surfactant: acetylene glycol type manufactured by Nisshin Chemical Industry Co., Ltd.), remaining amount of ion exchange water (remaining amount is The total amount of all components of the ink is 100.0%). Tables 4 to 6 show the compositions and the evaluation results of the inkjet ink compositions using the urethane resin emulsions A1 to A18, B1 to B10, and C1 to C10. In addition, about the ink composition of Examples 29-38 shown in Table 6, after synthesize | combining an emulsion, methyl ethyl ketone was removed and 2-pyrrolidone was added when preparing an ink composition.

3.5. Evaluation method <Evaluation>
Each ink jet ink composition obtained above is filled in an ink cartridge and mounted on an ink jet recording apparatus (trade name PX-G930, manufactured by Seiko Epson Corporation) which discharges the ink from the recording head by the action of energy of the piezo element did. In each case, the mass per drop is 28 ng ± in a unit area of 1/600 inch × 1/600 inch
The recording duty of a solid image recorded under the condition of applying one ink droplet of 10% is defined as 100%. The recording conditions were: temperature: 23 ° C., relative humidity: 55%. The following evaluations were performed for each example, and in those evaluation criteria, A and B were acceptable levels, and C and D were unacceptable levels.

(Abrasion resistance test)
Based on JIS L 0849 2013, it was carried out under the conditions of 200 g load and 100 reciprocations using a vibration industry type abrasion resistance evaluation device AB-301 of the tester industry. A recorded matter obtained by recording a solid image of 1.0 inch × 0.5 inch having a recording duty of 100% on a film (trade name: OPP plain roll 25 μm thick, manufactured by Toyobo Co., Ltd.) using the above-described inkjet recording apparatus Obtained. The platen temperature was printed at 60 ° C. and a dot density of 1440 dpi × 1440 dpi. Ten minutes after recording and one day after, evaluation was carried out by pressing a gold swatch over the solid image of the recorded matter. Thereafter, the stain of the gold-plated cotton, the stain of the non-recording portion and the peeling condition of the printed portion were visually confirmed, and the scratch resistance was evaluated according to the evaluation criteria shown below.
A: There was almost no stain on non-recording area and no stain on non-recording area, and there was almost no peeling on printed area. B: There was little soiling on non-recording area and stain on non-recording area. There was no stain C: Gold stain cotton stains and stains on non-recording area, and some peeling condition of printed area was found D: Ginkgo cotton stain and considerable non-recording area stains were found

(Intermittent discharge stability test)
A part of the printer PX-G 930 (manufactured by Seiko Epson Corporation) was modified to make a printer capable of printing a film. Using this printer, the ejection stability was evaluated during intermittent printing under an environment of a temperature of 40 ° C. and a relative humidity of 20%. First, it was confirmed that the inkjet ink composition was ejected normally from all the nozzles. Then, after the inkjet ink composition is discharged onto A4 size photographic paper (photo glossy paper manufactured by Seiko Epson Corporation), a rest time of 2 minutes is provided under an environment of 40% temperature and 20% relative humidity, and again The inkjet ink composition was discharged onto A4 size photographic paper. In the second discharge, the positional deviation of the dots between the position of the first drop of dots deposited on A4 size photographic paper and the target position was measured with an optical microscope. The intermittent characteristics were evaluated based on the following evaluation criteria based on the positional deviation of the obtained dots.
A: The positional deviation of dots was 10 μm or less.
B: The positional deviation of dots was more than 10 μm and not more than 20 μm.
C: The positional deviation of dots was more than 20 μm and not more than 30 μm.
D: Dot misalignment exceeded 30 μm.

(Continuous printing stability test)
A part of the printer PX-G 930 (manufactured by Seiko Epson Corporation) was modified to make a printer capable of printing a film. The ink cartridge of this printer was filled with the inkjet ink composition obtained above. Then, the inkjet ink composition was discharged onto an A4-size photo paper (photo glossy paper manufactured by Seiko Epson Corporation) at a resolution of 720 dpi × 720 dpi, and a recording sample having a cyan solid pattern was produced. This operation is repeated up to 8 hours under the environment of a temperature of 40 ° C. and a relative humidity of 20% to discharge the ink jet ink composition, and the time until the droplets of the ink jet ink composition are stably discharged from the nozzle is stabilized. It was measured. Based on the obtained time, the continuous printing stability was evaluated according to the following evaluation criteria.
A: Even after 8 hours from the discharge start, no discharge failure or discharge failure was observed even once.
B: Discharge failure or discharge disturbance was observed in 2 hours or more and less than 8 hours from the discharge start.
C: Ejection failure or disturbance of ejection was observed within 1 hour or more and less than 2 hours from the start of ejection.
D: Discharge failure, discharge disturbance, etc. were observed within 1 hour from the discharge start.

(Clogging recoverability test)
Using the printer PX-G 930 (Seiko Epson Co., Ltd.), the ink cartridge of this printer is filled with the ink jet ink composition obtained above, and printed on an A4-size OPP film at a resolution of 720 dpi x 720 dpi. It was confirmed that the ink jet ink composition was discharged by all the nozzles. Thereafter, the printer was left for 30 days under an environment of a temperature of 40 ° C. and a relative humidity of 20%. After standing, the inkjet ink composition was discharged again from all the nozzles, and cleaning was repeated until printing equivalent to the initial one was possible, and the number of cleanings at that time was measured. Based on the number of times of cleaning, the clogging recovery was evaluated according to the following evaluation criteria.
A: The ink composition was ejected from all the nozzles in one to three cleanings.
B: The ink composition was ejected from all the nozzles in four to six cleanings.
C: The ink composition was ejected from all the nozzles after seven or more cleanings.
D: In the cleaning, the ink composition could not be ejected from any of the nozzles.

(20 ° gloss test)
Solid printed (1440 dpi x 1440 dpi) printed on corona treated OPP (FOS-AQ 60 μm thick, made by Futamura Chemical Co., Ltd.) at a platen temperature of 55 ° C using PX-G930, and dried at 90 ° C for 10 minutes. The 20 ° gloss was measured. The gloss was measured with a handy type gloss meter MULTI GLOSS 268 (manufactured by Konica Minolta Co., Ltd.).
A: 20 ° gloss of 70 or more on the OPP film.
B: 20 ° gloss on the OPP film is 55 or more and less than 70.
C: 20 ° gloss of 40 or more and less than 55 on an OPP film.
D: 20 ° gloss of less than 40 on OPP film.

3.6. Evaluation result A group derived from one or more selected from dicyclohexylmethane diisocyanate, isophorone diisocyanate, 1,3-bis (isocyanatomethyl) cyclohexane, m-bis (isocyanatopropyl) benzene and m-bis (isocyanatomethyl) benzene At least one type of skeleton selected from a skeleton derived from polyoxypropylene glycol and a skeleton derived from polycarbonate diol, having a weight average molecular weight of at least one selected from a urethane group and a urea group; The inkjet ink composition of each of the examples containing a polymer having a skeleton of 500 or more and 3000 or less and an acid value of 5 mgKOH / g or more and 30 mgKOH / g or less has intermittent discharge stability, abrasion resistance and glossiness. The sex was good.

  And a group derived from one or more selected from dicyclohexylmethane diisocyanate, isophorone diisocyanate, 1,3-bis (isocyanatomethyl) cyclohexane, m-bis (isocyanatopropyl) benzene and m-bis (isocyanatomethyl) benzene. At least one skeleton selected from a skeleton derived from a polyoxypropylene glycol and a skeleton derived from a polyoxypropylene glycol, having one or more groups selected from a urethane group and a urea group; In the inkjet ink composition of each comparative example containing a polymer having a molecular weight of 500 or more and 3,000 or less or an acid value of more than 5 mg KOH / g and more than 30 mg KOH / g, intermittent discharge stability is insufficient Tend to be scratch resistant and Or gloss was found to be insufficient.

The present invention is not limited to the embodiments described above, and various modifications are possible. For example, the invention includes configurations substantially the same as the configurations described in the embodiments (for example, configurations having the same function, method and result, or configurations having the same purpose and effect). The present invention also includes configurations in which nonessential parts of the configurations described in the embodiments are replaced. The present invention also includes configurations that can achieve the same effects or the same objects as the configurations described in the embodiments. Further, the present invention includes a configuration in which a known technique is added to the configuration described in the embodiment.

Claims (10)

A group derived from one or more selected from dicyclohexylmethane diisocyanate, isophorone diisocyanate, 1,3-bis (isocyanatomethyl) cyclohexane, m-bis (isocyanatopropyl) benzene and m-bis (isocyanatomethyl) benzene; And at least one group selected from a urethane group and a urea group,
At least one skeleton selected from a skeleton derived from polyoxypropylene glycol and a skeleton derived from polycarbonate diol, containing a skeleton having a weight average molecular weight of 500 to 3,000,
Polymer having an acid value of 5 mg KOH / g or more and 30 mg KOH / g or less,
An ink-jet ink composition containing In claim 1,
An inkjet ink composition, wherein the polymer contains a skeleton derived from a carboxyl group-containing glycol. In claim 2,
An inkjet ink composition, wherein the skeleton derived from the carboxyl group-containing glycol is a skeleton derived from dimethylol propionic acid. In any one of claims 1 to 3,
An inkjet ink composition, wherein the polymer contains at least one skeleton selected from a skeleton derived from an aliphatic diamine and a skeleton derived from an aromatic diamine. In any one of claims 1 to 4,
An inkjet ink composition, wherein the polymer contains a skeleton derived from an alkyl diamine having 1 to 8 carbon atoms. In any one of claims 1 to 5,
An inkjet ink composition, further comprising a lactam. In claim 6,
An inkjet ink composition, wherein the lactam comprises 2-pyrrolidone. A group derived from one or more selected from dicyclohexylmethane diisocyanate, isophorone diisocyanate, 1,3-bis (isocyanatomethyl) cyclohexane, m-bis (isocyanatopropyl) benzene and m-bis (isocyanatomethyl) benzene; And at least one group selected from a urethane group and a urea group,
At least one skeleton selected from a skeleton derived from polyoxypropylene glycol and a skeleton derived from polycarbonate diol, containing a skeleton having a weight average molecular weight of 500 to 3,000,
Polymer whose acid value is 5 mgKOH / g or more and 30 mgKOH / g or less.   It is a manufacturing method to be reacted in a solvent containing 2-pyrrolidone, which is dicyclohexylmethane diisocyanate, isophorone diisocyanate, 1,3-bis (isocyanatomethyl) cyclohexane, m-bis (isocyanatopropyl) benzene and m-bis (isocyanate methyl) A method for producing a polymer having a group derived from one or more selected from benzene and having one or more groups selected from a urethane group and a urea group. A recording method of recording an image on a recording medium by discharging the inkjet ink composition according to any one of claims 1 to 7 from a recording head of an inkjet system.