JP2008088365A - Composition containing polymer compound and image formation method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a composition which is useful as an inkjet ink, shows a favorable discharge stability and yields a recorded image showing a high image fastness such as water resistance, light fastness and rub resistance and an excellent gloss, and an image formed by an image formation method whereby the composition is applied to a recording medium. <P>SOLUTION: The composition comprises a block polymer compound and an aqueous solvent, wherein the block polymer compound includes at least a hydrophilic block segment and a hydrophobic block segment, contains a crosslinkable functional group and forms an empty micelle in which the hydrophobic block segment serves as a core or an empty micelle particle comprising a resin dispersion formed by binding of a plurality of empty micelles in the aqueous solvent. The empty micelle has a crosslinking structure in which the block polymer compound is crosslinked by the crosslinkable functional group. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a composition containing a block polymer compound and useful as various inkjet inks, and an image forming method.

  In recent years, digital printing technology has made great progress. Typical examples of the digital printing technology are electrophotographic technology and ink jet technology, but in recent years, the presence of image forming technology in offices, homes, and the like has been increasing.

  For example, the ink jet technology has a large feature of compactness and low power consumption as a direct recording method. In addition, the image quality is rapidly increasing due to the miniaturization of nozzles. These ink jet technologies include those that evaporate and foam by heating the ink and eject the ink, and those that eject the ink by vibrating the piezo element.

Usually, a resin is added to the ink used in these ink jet technologies for the purpose of improving performance such as fastness, water resistance, weather resistance, and glossiness of a recorded image on a recording medium. The structure to do is taken. A method of adding resin fine particles (also called latex) and a water-dispersible resin having a carboxyl group and a nonionic hydrophilic group have been proposed (Patent Documents 1 and 2).
JP-A-3-79678 JP-A-5-239392

  However, such additive resins that have been conventionally used have not necessarily been sufficiently satisfactory in terms of performance. This is because all of the conventional additive resins increase the amount of the resin, so that the dispersion stability is impaired, or secondary effects such as an increase in viscosity occur. It was because it stayed.

  In addition, the resin fine particles as described in Patent Document 1 are difficult to control the particle size and particle size distribution of the resin fine particles, which is one of the factors that lower the dispersion stability of the obtained resin fine particles. But it was. Furthermore, a purification operation such as removing coarse particles after polymerization may be necessary.

  In addition, as described in Patent Document 2, when a water-dispersible resin having a carboxyl group and a nonionic hydrophilic group is added, the viscosity of the ink is increased and the long-term storage stability of the resin in the ink is increased. There were problems such as being insufficient.

  In order to stabilize the dispersion of the obtained resin fine particles, an excessive amount of a surfactant can be added. In this case, however, the surface tension of the ink decreases, and the ink penetrates into a recording medium such as paper. As a result, there has been a problem that high-density recording cannot be performed.

  SUMMARY OF THE INVENTION The present invention has been made in view of the above-described problems, and is an inkjet ink having good image fastness such as water resistance, light resistance, and abrasion resistance of a recorded image, excellent image glossiness, and good ejection stability. An object of the present invention is to provide a useful composition. Another object of the present invention is to provide an image formed by an image forming method for applying the composition to a recording medium.

  As a result of intensive studies to solve the above problems, the present inventors have prepared a block polymer compound having at least a hydrophilic block segment and a hydrophobic block segment and having a crosslinkable functional group as the additive resin. Then, it was considered to use a cross-linked block polymer compound.

  That is, the present inventors have completed the present invention shown below.

  The present invention is a composition comprising at least a block polymer compound having a hydrophilic block segment and a hydrophobic block segment and having a crosslinkable functional group, and an aqueous solvent, the block polymer compound comprising the aqueous solvent A crosslinked structure in which a micelle state is formed only with the block polymer compound in which the hydrophobic block segment is arranged in the core portion and the block polymer compound is crosslinked with the crosslinkable functional group. It is a composition characterized by having.

  The present invention is the composition wherein the resin dispersion has an average particle size of 500 nm or less and a polydispersity index of 1 or less. In addition, the crosslinked structure of the resin dispersion is formed of only the hydrophobic block segment. Further, only the hydrophobic block segment has a crosslinkable functional group. The crosslinkable functional group is a self-crosslinkable functional group. The self-crosslinkable functional group is a radical polymerization unsaturated group or a hydrolyzable alkoxysilane group.

  The present invention is a composition characterized by further containing a crosslinking agent that causes a crosslinking reaction of the crosslinkable functional group.

  The present invention is the composition, wherein the block polymer compound comprises an ionic hydrophilic block segment and a nonionic hydrophilic block segment as the hydrophilic block segment. In addition, the block polymer compound is bonded in the order of the hydrophobic block segment, the nonionic hydrophilic block segment, and the ionic hydrophilic block segment. In particular, the block polymer compound has an ABC type triblock structure having a crosslinkable functional group in the hydrophobic block segment or the nonionic hydrophilic block segment.

  The present invention is a composition characterized in that the main chain structure of each block segment of the block polymer compound is a polyalkenyl ether structure.

  The present invention is a method for producing the composition, wherein a dispersion step of forming a core by aggregation of hydrophobic block segments of the block polymer compound in the aqueous solvent to form a resin dispersion, and the block polymer It is a manufacturing method of the composition which has at least the bridge | crosslinking process which bridge | crosslinks a compound.

  The resin dispersion is produced by a crosslinking reaction of a block polymer compound in which a hydrophobic functional segment is substituted on a hydrophobic block segment. The resin dispersion is produced by a crosslinking reaction of a block polymer compound in which a nonionic hydrophilic block segment is substituted with a crosslinking functional group. The resin dispersion is produced by a crosslinking reaction of a block polymer compound in which a crosslinking functional group is substituted on an ionic hydrophilic block segment.

  The resin dispersion is produced by a cross-linking reaction between a block polymer compound having a cross-linkable functional group substituted on a hydrophobic block segment and a cross-linking agent. The resin dispersion is produced by a cross-linking reaction between a block polymer compound having a non-ionic hydrophilic block segment substituted with a cross-linkable functional group and a cross-linking agent. The resin dispersion is produced by a cross-linking reaction between a block polymer compound in which a cross-linkable functional group is substituted on an ionic hydrophilic block segment and a cross-linking agent. At this time, the cross-linking agent is a hydrophobic compound. The cross-linking agent is a polymer compound.

  The present invention is an ink composition comprising at least a colorant and the above composition. Further, the color material is a dye. In particular, the ink composition is an ink-jet ink composition.

  The present invention is a method for producing the ink composition, comprising at least a step of dissolving or dispersing the coloring material and a step of mixing the obtained solution or dispersion and the composition. It is a manufacturing method of the ink composition characterized by having.

  The present invention relates to an image forming method in which the ink composition is applied to a recording medium, wherein the resin dispersion remains on the recording medium, and the color material penetrates into the recording medium. Is an image forming method.

  The present invention is an image forming method characterized in that an ink composition containing a color material is applied to a recording medium to form an image, and then the composition is applied onto the image. At this time, the composition is applied as a post-printing treatment liquid.

  The present invention is the image forming method, wherein the average particle diameter of the resin dispersion and the average surface pore diameter of the recording medium satisfy the following relational expression (A).

[Average particle diameter of resin dispersion] − [Average surface pore diameter of recording medium] ≧ 1 nm (A)
The present invention is the image forming method, wherein the resin dispersion has an average particle size of 20 nm or more. The present invention is the image forming method, wherein the polydispersity index of the resin dispersion is 0.3 or less.

  The present invention is an image forming method comprising a step of recording an image by applying the above composition and the composition produced by the above method to a medium.

  The present invention is an image forming apparatus having means for recording an image by applying the composition and the ink composition to a medium.

  According to the invention as described above, it is possible to provide a composition or a treatment liquid that has excellent water resistance, light resistance, gloss, good ejection stability, dispersion stability, and long-term storage stability. In addition, the present invention can provide an ink composition and an image forming method using the above composition.

  Hereinafter, the present invention will be described in detail.

  Hereinafter, the present invention will be described in detail with reference to the drawings. FIG. 1 is a schematic view of a composition containing the resin dispersion of the present invention, and FIG. 2 is an enlarged schematic view of the resin dispersion of FIG.

  In FIGS. 1 and 2, 40 and 40 'are dispersions of the present application dispersed in an aqueous solvent 60, 40 is a microsphere-like form, and 40' is a state in which some of these are gathered. Yes.

  The dispersion 40 is formed of a block polymer compound 10 having a hydrophobic block segment 11 and a hydrophilic block segment 12. Specifically, by a hydrophobic reaction with an aqueous solvent, a micro part formed by a core part formed by gathering hydrophobic block segments inside and a shell part coordinated by hydrophilic block segments on the outside. It becomes a sphere and is dispersed in an aqueous solvent. Since the hydrophobic component is present so as to be wrapped with the hydrophilic component, the dispersion stability of the dispersion is good. Moreover, since such dispersions usually have almost the same size due to their surface tension, even if the amount of resin is increased, the size does not become extremely large. The change in stability is sufficiently smaller than that of conventional resin fine particles. Therefore, according to the configuration of the present invention, transparent resin fine particles having a uniform structure, a small particle size distribution, easy particle size control, and stable dispersion can be obtained.

  In addition, in order to distinguish this resin dispersion from micelles containing color materials, etc., in this specification, the dispersion resin is referred to as “empty micelles” in the sense that it does not contain inclusions, and is formed by empty micelles. The resin fine particles thus formed are referred to as “empty micelle particles”.

  And the block polymer compound of this invention becomes a structure which block polymer compounds bridge | crosslink and couple | bond together by having a crosslinkable functional group in a hydrophobic block segment and / or a hydrophilic block segment. With this configuration, for example, the micelle state does not collapse even under severe environmental factors such as receiving a strong shearing force or exposing the composition to a high heat atmosphere such as thermal ink jet. Stable performance can be maintained even in difficult environments.

  This demonstrates its performance especially in terms of storage stability. In addition, this cross-linking structure makes it possible to stably use block polymer compounds that form micelles in a stationary state, but that can be stably used, such as vibrations and micelles that collapse at high temperatures. It also contributes to widening the range.

  Further, since it is not necessary to add an extra surfactant, which has been essential for stabilizing conventional resin fine particles, an image with high density and little bleeding can be obtained.

  In this way, when the block polymer compound is cross-linked, the cross-linkable functional group described above may be self-cross-linkable, or may be cross-linked by newly adding a cross-linking agent.

  From the viewpoint of dispersion stability, it is preferable that the cross-linking reaction between micelles is inhibited by the steric hindrance of the hydrophilic block segment constituting the shell portion of the resin dispersion.

  The resin dispersion of the present invention is preferably formed by a single spherical micelle, but some of these micelles are formed by chemical or physical coalescence so long as they do not affect the dispersion state. Composite resin fine particles are also included.

  The core-shell type polymer micelle in the present invention is a general term for micrometer, submicron, and nanometer order fine particles formed using a polymer as a dispersant. The cross-linked structure in the empty micelle particles may be formed in either the core part or the shell part. However, the surface formed on the hydrophobic core part is relatively easy to manufacture from the side where crosslinking between the empty micelle particles is less likely to occur due to the three-dimensional effect of the hydrophilic shell part, and the average particle size of the empty micelle particles. It is more preferable because the control of the diameter and particle size distribution is relatively easy. Even when a cross-linked structure is formed in the hydrophilic shell portion, the cross-linking reaction is performed at a very dilute concentration, so that coalescence between particles can be suppressed and the average particle size and particle size distribution can be controlled. The empty micelle particles in the present invention may be composite resin fine particles formed by chemical or physical coalescence of particles, but the average particle size of empty micelle particles is 500 nm or less, and the polydispersity index is 1. Must be: The smaller the amount of the composite fine particles contained in the composition of the present invention, the more easily the effect is exhibited. The empty micelle particles of the present invention have an average particle size of 500 nm or less and a polydispersity index of 1 or less by purification operations such as filtration and centrifugation even when the average particle size of the empty micelle particles exceeds 500 nm. Also included are resin fine particles.

  In addition, the crosslinking structure in the empty micelle particles is a crosslinking agent that undergoes a crosslinking reaction with the radically polymerizable unsaturated group or hydrolyzable alkoxysilane group that the block polymer has, or the crosslinking functional group that the block polymer has. It is formed by a crosslinking reaction using

  FIG. 3 is a schematic view showing a state when the composition of the present invention is applied onto a recording medium. In FIG. 3, a recorded matter is obtained through the steps shown on the right.

  In FIG. 3, when the ink composition of the present invention is applied to the recording medium 50, the dye 20 penetrates into the recording medium 50, and the empty micelle 40 does not penetrate into the recording medium 50. A state in which a film is formed on the surface of the recording medium 50 is shown. At this time, in the ink composition containing the empty micelle 40 and the color material (for example, the dye 20), the difference between the average particle diameter of the empty micelle and the average surface pore diameter of the voids 51 existing on the surface of the recording medium is 1 nm or more. It is desirable to control the particle size.

  And since this resin component functions as an image protective layer, the recorded matter obtained is excellent in water resistance and light resistance and has good glossiness.

  In addition, the present inventors refer to the most preferable cross-linked form constituting empty micelles as cross-linking in micelles, and distinguish it from conventional cross-linked forms. By adopting the micelle cross-linking structure as in the present invention, the cross-linking between empty micelles can be substantially ignored, the structure is uniform, the particle size distribution is small, and the transparent resin has a controlled particle size Fine particles can be provided. Furthermore, since the block polymer itself, which is a dispersant, has a crosslinked form, it is very stable in dispersion in an aqueous solvent as compared with conventional resin fine particles. Therefore, unless there are special circumstances such as adjustment of the surface tension, it is not necessary to add a surfactant to stabilize the empty micelles of the present invention. The empty micelles of the present invention are defined as not containing a color material or the like, being substantially transparent and different from colored fine particles.

  The average particle diameter of the empty micelle particles contained in the composition of the present invention is preferably 20 nm to 500 nm, more preferably 20 to 200 nm, and still more preferably 20 to 100 nm. When the average particle diameter of the empty micelle particles exceeds 500 nm, the ejection stability may be inferior, and when it is less than 20 nm, it may be smaller than the hole diameter of the recording medium. Therefore, some or most of the empty micelle particles penetrate into the recording medium, which may reduce the effect of the present invention.

  In addition, when the polydispersity index of the empty micelle particles is too wide, there are cases where the ejection property is impaired and some of the empty micelle particles penetrate into the recording medium. Therefore, the range of the polydispersity index of the empty micelle particles in the present invention is preferably 1 or less, more preferably 0.05 to 0.30, further preferably 0.05 to 0.10, and 0.05 to 0. 10 is more preferable. The polydispersity index here is an index indicating the particle size distribution of the empty micelle particles. The narrower the particle size distribution, that is, the smaller the particle size, the smaller the value and the particle size distribution becomes. The wider the value, the larger the value.

  The average particle diameter / polydispersity index of the empty micelle particles of the present invention uses values measured by dynamic light scattering (DLS) under the concentration condition of 20 ° C. and 0.01% by mass. However, other measurement methods, specifically, laser diffraction method, laser Doppler method, centrifugal sedimentation method, field-flow fractionation method, electrical detector method, etc. It is only necessary that the value is corrected to the corrected value.

  The preferable content of the empty micelle particles contained in the composition of the present invention is in the range of 0.1% by mass to 90% by mass. When the content of the empty micelle particles is less than 0.1% by mass, the amount of empty micelle particles remaining on the recording medium becomes insufficient, so that a sufficient effect may not be obtained. On the other hand, if it exceeds 90% by mass, the viscosity of the solution increases, so that sufficient ejection stability may not be obtained. Therefore, the more preferable content of the empty micelle particles is 1% by mass or more and 80% by mass or less.

  In the case of pigment ink, as a method for improving the protection and gloss of the recorded image and the adhesion to the recording medium, a method of applying a transparent coating liquid containing resin fine particles on the recording image surface of the recording medium Has been proposed (for example, JP-A-2004-330554). The configuration of the present invention is also effective when used as such a coating liquid (treatment liquid).

  Hereinafter, the block polymer compound applicable to the present invention will be described in detail.

  The block polymer compound in the present invention means a polymer compound composed of two or more different block segments. Further, the block segment in the present invention means a structure composed of repeating units of one or more single or plural monomer compounds. Examples of the block segment having a repeating unit derived from a plurality of monomers include a random copolymer and a gradient copolymer whose composition ratio gradually changes. However, it is more preferable that the block segment is composed of a single monomer in order to make functional separation that is a feature of the block polymer structure stand out. In addition, the block polymer compound of the present invention may be a polymer in which the above block polymer is graft-bonded to another polymer.

  Moreover, it is possible to exhibit two or more functions by having three or more block segments. For this reason, it is possible to form a higher-order and precise structure than a polymer compound composed of two block segments. In addition, by maintaining a property similar to a plurality of block segments, it is possible to make the property more stable.

  The block polymer compound of the present invention has at least one hydrophilic block segment and at least one hydrophobic block segment. The hydrophilicity in the present invention is a property that has a high affinity for water and is easily dissolved in water, and the hydrophobic property is a property that has a low affinity for water and is difficult to dissolve in water.

  For example, the hydrophilic block segment includes a block segment containing a repeating unit structure having a hydrophilic unit such as a structure containing a large amount of carboxylic acid, carboxylate salt, or hydrophilic oxyethylene unit, and a structure having a hydroxyl group. It is done. Specific examples include acrylic acid and methacrylic acid, carboxylates such as inorganic salts and organic salts thereof, polyethylene glycol macromonomers, and hydrophilic monomers such as vinyl alcohol and 2-hydroxyethyl methacrylate. This is a block segment having a repeating unit structure. However, the hydrophilic block segment in the composition of the present invention is not limited to the above structure.

  Moreover, as a hydrophobic block segment, the block segment containing the repeating unit structure which has hydrophobic units, such as an isobutyl group, t-butyl group, a phenyl group, a biphenyl group, a naphthyl group, is mentioned, for example. A specific example is a block segment having a hydrophobic monomer such as styrene or t-butyl methacrylate as a repeating unit, but the hydrophobic block block segment in the composition of the present invention is not limited to the above structure.

  The crosslinking in the present invention means that the crosslinkable functional group of the block polymer compound is crosslinked by a crosslinking reaction. Preferred substituents exhibiting crosslinkability include a crosslinkable functional group capable of forming a crosslink by reacting with a crosslinker, and a crosslinkable functional group capable of forming a crosslink without a crosslinker (particularly a self-crosslinkable functional group). May be referred to).

  Examples of the crosslinkable functional group include a carboxyl group, a hydroxyl group, a tertiary amino group, a blocked isocyanate group, an epoxy group, and a 1,3-dioxolan-2-one-4-yl group. Among these, a carboxyl group, a hydroxyl group, and an epoxy group are preferable because of high reactivity and easy introduction into the resin.

  Next, typical examples of combinations of crosslinkable functional groups and crosslinking agents are listed below.

  When the crosslinkable functional group is a carboxyl group, examples of the crosslinking agent include amino resins, compounds having two or more epoxy groups in one molecule, 1,3-dioxolan-2-one-4-yl groups in one molecule ( And a compound having 2 or more of cyclocarbonate groups).

  When the crosslinkable functional group is a hydroxyl group, examples of the crosslinking agent include amino resins, polyisocyanate compounds, and blocked polyisocyanate compounds.

  When the crosslinkable functional group is a tertiary amino group, the crosslinking agent includes a compound having two or more epoxy groups in one molecule, and a 1,3-dioxolan-2-one-4-yl group in one molecule. Examples thereof include compounds having two or more.

  When the crosslinkable functional group is a blocked isocyanate group, examples of the crosslinking agent include compounds having two or more hydroxyl groups in one molecule.

  When the crosslinkable functional group is an epoxy group or a 1,3-dioxolan-2-one-4-yl group, examples of the crosslinking agent include compounds having two or more carboxyl groups in one molecule, polyamine compounds, polymercapto compounds, etc. Is mentioned.

  Examples of the self-crosslinkable functional group include a radical polymerizable unsaturated group and a hydrolyzable alkoxysilane group. For the purpose of reinforcing self-crosslinkability, a compound having two or more radically polymerizable unsaturated groups and a compound having two or more hydrolyzable alkoxysilane groups can be partially used in combination.

  Examples of the hydrolyzable alcosilane group include methacryloxypropyltrimethoxysilane, vinyltriethoxysilane, vinyltrimethoxysilane, and vinyltris (β-methoxyethoxy) silane.

  As one of the preferable forms of the block polymer compound which comprises the empty micelle of this invention, the structure whose main chain structure of each block segment is a polyalkenyl ether structure can be mentioned. More preferably, one or more hydrophilic block segments contain a nonionic hydrophilic group and an ionic hydrophilic group. Or it is preferable to have a nonionic hydrophilic block segment and an ionic hydrophilic block segment as a hydrophilic block segment. By having a nonionic hydrophilic block segment, even if an environmental change such as pH occurs, the dispersion stability is not impaired, and a composition excellent in dischargeability particularly in the thermal ink jet method is obtained.

  A preferred example of the block polymer compound constituting the empty micelle of the present invention is an ABC triblock polymer. Note that ABC means a different block segment. A preferable structure as a dispersant is an ABC type triblock polymer having a hydrophobic block segment containing a crosslinkable group in the A block, a nonionic hydrophilic block segment in the B block, and an ionic hydrophilic block segment in the C block.

  The hydrophobic block segment corresponding to the A block may be a repeating unit structure having a hydrophobic crosslinkable functional group, more preferably a repeating unit structure having a crosslinkable functional group, and a hydrophobic crosslinkable functional group. A copolymer having a repeating unit structure having no group is preferred. Specific examples include random copolymers, block copolymers, and gradient copolymers.

  Further, the content of the repeating unit structure having a crosslinkable functional group contained in the hydrophobic block segment of the block polymer compound is preferably 1 to 100 mol%, more preferably 5 to 80 mol% with respect to the entire hydrophobic block segment. preferable. If the amount is less than 1 mol%, crosslinking may be insufficient, and some of the empty micelles may be disintegrated after ejection and the polymer may penetrate into the recording medium.

  Specific examples of the repeating unit structure having a crosslinkable functional group contained in the hydrophobic block segment used in the present invention include the following structures, but the present invention is not limited thereto.

  Examples of the hydrophobic block segment having no crosslinkable functional group include a block segment having a hydrophobic monomer such as styrene or t-butyl methacrylate as a repeating unit. Preferably, it is a block segment having a repeating unit structure composed of a polyalkenyl ether structure, and specific examples thereof include the following structures, but the present invention is not limited thereto.

  Examples of the B block which is a nonionic hydrophilic block segment include a block segment containing a repeating unit structure having a hydroxyl group, a polyoxyethylene chain or the like as a substituent or a side chain. Specifically, it is a block segment having a repeating unit structure composed of a polyalkenyl ether structure. Specific examples of the repeating unit structure that becomes a nonionic hydrophilic block include the following, but the present invention is not limited thereto.

  Examples of the C block that is an ionic hydrophilic block segment include a block segment containing a repeating unit structure having a carboxylic acid, a dicarboxylic acid, a sulfonic acid, an amine, and a salt thereof. Either anionic or cationic may be used, but it is not limited to these, but anionic hydrophilic block segments are preferred from the viewpoint of dispersion stability and ink jet characteristics. A block segment having a repeating unit structure composed of a polyalkenyl ether structure is preferred. Specific examples of the repeating unit structure that becomes an ionic hydrophilic block include the following, but the present invention is not limited thereto.

  The counter cation may be an atom or a compound, and specific examples include a lithium cation, a sodium cation, a potassium cation, and a calcium cation. In the present invention, the counter cation is limited to a specific atom or compound. It is not something.

  Specific examples of the block polymer compound used in the present invention are listed below, but the block polymer compound used in the present invention is not limited to the following structure (r in the figure represents a random structure, and b represents a block structure). ).

  The content of the hydrophobic block segment contained in the block polymer compound in the present invention is preferably in the range of 5 to 95% by mass, and more preferably in the range of 10 to 90% by mass. Further, the content of the hydrophilic block segment is preferably in the range of 5 to 95% by mass, more preferably in the range of 10 to 90% by mass. Although details are unknown, the present inventors have intensively studied that a stable empty micelle structure may not be obtained when the content of the hydrophobic block segment or the hydrophilic block segment is outside the above range. I know from the results.

  When the block polymer compound is an ABC type triblock polymer compound, the content of the hydrophobic block segment A in the block segment ABC is preferably 5 to 94% by mass, more preferably 5 to 89% by mass. . The content of the nonionic hydrophilic block segment B is preferably 5 to 94% by mass, more preferably 10 to 90% by mass. The content of the ionic hydrophilic block segment C is preferably 1 to 90% by mass, more preferably 1 to 80% by mass.

  Further, the number average molecular weight (Mn) of the block polymer compound constituting the empty micelle of the present invention is preferably 500 or more and 10000000 or less, and more preferably 1000 or more and 1000000 or less. When it exceeds 10,000,000, the entanglement between the polymer chains and between the polymer chains becomes excessive, and it may be difficult to disperse in the solvent. On the other hand, when Mn is less than 500, the molecular weight may be small and the steric effect as a polymer may be difficult to appear.

  The block polymer polymerization method preferably used in the present invention will be described. A number of methods for synthesizing polymers containing a polyvinyl ether structure have been reported (for example, JP-A-11-080221). A method by cation living polymerization by Aoshima et al. (Polymer Bulletin Vol. 15, 417, 1986, Japanese Patent Laid-Open Nos. 11-322942 and 11-322866) is representative. Accurate length (molecular weight) of various polymers such as homopolymers, copolymers composed of two or more monomers, block polymers, graft polymers, gradient polymers, etc. It can be synthesized to match.

  In the composition of the present invention, a cross-linking agent selected by a combination of the cross-linkable functional group and the cross-linking agent described above can be added depending on the type of the cross-linkable functional group to be used. The crosslinking agent is added before or after the formation of the empty micelle of the block polymer. At that time, since it is easy to control the particle size of the empty micelle particles, it is more preferable before forming the empty micelles.

  In the micelle cross-linking in the present invention, the block polymer compound is dispersed in an aqueous medium composed of water and, if necessary, a water-soluble organic solvent to form empty micelles, followed by heating under normal pressure or under pressure. Performed by energy beam irradiation. In this case, crosslinking may be performed in the presence of a catalyst or a polymerization initiator.

  Regarding the solid content concentration in the composition when crosslinking is performed, when the solid content concentration in the composition is high, the distance between the empty micelles is short, and the empty micelles may be aggregated by crosslinking. Therefore, the concentration is adjusted by adding water or the like in advance, and is preferably set to a range of 20% by mass or less, more preferably 0.1 to 10% by mass.

  Self-crosslinking by a carboxyl group and an epoxy group, self-crosslinking by a hydroxyl group and an N-alkoxymethylamide group, and self-crosslinking by a hydrolyzable alkoxysilane group are, for example, crosslinking by heating at 50 to 150 ° C. under normal pressure or pressure. Can be mentioned. In this case, it is also recommended to use a catalyst.

  In the case of self-crosslinking with a radically polymerizable unsaturated group, a water-soluble polymerization initiator such as potassium persulfate or ammonia persulfate is added, and the polymerization is made redox, and the temperature is about 50 to 90 ° C. Can be crosslinked.

  On the other hand, the crosslinking using a crosslinking agent is preferably performed by heating at 50 to 100 ° C. under normal pressure, but in some cases, the crosslinking can be performed at about 100 to 150 ° C. under pressure. In this case, it is also recommended to use a catalyst.

  The crosslinking agent that can be added to the composition of the present invention is preferably a hydrophobic compound. That is, the crosslinking agent used in the composition of the present invention is preferably a hydrophobic one because the crosslinkable functional group of the polymer compound is contained in the hydrophobic block segment, but a water-soluble or water-dispersible one is used. You can also

  Moreover, it is preferable that the crosslinking agent contained in the composition of this invention is a polymer compound.

  The blending ratio of the block polymer compound and the crosslinking agent is generally preferably in the range of 30:70 to 95: 5, particularly preferably in the range of 40:60 to 90:10, in terms of the solid mass ratio.

  The coloring material contained in the ink composition of the present invention may be any of a dye, a pigment, and a self-dispersing pigment as long as it is stably present in an aqueous solution, but it easily penetrates into a recording medium and exhibits an effect. Since it is easy to do, it is more preferable that it is a dye. Further, when a pigment and a self-dispersing pigment are used, the effect expected when the particle diameter of the pigment dispersion is smaller than the average surface pore diameter of the recording medium is further obtained. The dye in the present invention is a colorant that is soluble in water or oil, whereas the pigment is an insoluble colorant that is insoluble in water or oil, and the self-dispersing pigment is a surface functional group. It can be defined as a colorant that is dispersed and stabilized in water or oil. When the ink composition of the present invention is applied to a recording medium, the difference between the average particle diameter of empty micelle particles and the average surface pore diameter of recording medium (average particle diameter of empty micelle particles−average surface pore diameter of recording medium) Is preferably 1 nm or more. In this way, empty micelles can remain on the surface of the recording medium without penetrating into the recording medium. This residual resin component forms a film on the recorded image to form an image protective layer, and can improve image fastness such as water resistance and light resistance of the image.

  The recording medium used in the present invention may be coated paper for inkjet recording, plain paper, general office copy paper, and the like, but is not limited thereto. More preferred. The inkjet recording coated paper here is a recording medium in which an ink receiving layer is provided on a substrate such as paper or film. In general, the ink receiving layer is roughly classified into two types, a swelling type and a void type. In the present invention, it is preferable that the outermost layer has a void. The receiving layer other than the outermost layer may be either a void type or a swelling type, or may be a combination of these.

  The structure of the ink receiving layer is mainly composed of an inorganic pigment and a binder polymer. As the inorganic pigment, porous pigments such as silica, alumina, calcium carbonate, and magnesium carbonate are used, but are not limited thereto. . Moreover, polyvinyl alcohol etc. are used as a binder polymer, However, It is not limited to this.

  In the ink receiving layer of the recording medium of the present invention, the content of the inorganic pigment is preferably in the range of 30 to 90% by mass with respect to the total mass of the ink receiving layer.

  In the ink receiving layer of the recording medium of the present invention, the average pore diameter of the receiving layer can be measured by a nitrogen adsorption method or a mercury intrusion method. The average pore diameter of the receiving layer is preferably in the range of 2.0 to 50.0 nm. Within this range, both the ink absorption speed and the dye fixing speed are increased.

  Specific examples of the dye used in the ink composition of the invention are shown below.

  As the dye, a direct dye, an acid dye, a basic dye, a reactive dye, a water-soluble dye for food coloring, or a disperse dye can be used. In addition, a newly synthesized dye may be used for the present invention.

  Examples of water-soluble dyes that can be used in the present invention include azo dyes, methine dyes, azomethine dyes, xanthene dyes, quinone dyes, and phthalocyanine dyes. Specific examples of commercially available dyes are shown below, but the dyes described in the present invention are not limited to the following.

That is, C.I. I. Direct black, -17, -62, -154; I. Direct yellow, -12, -87, -142; I. Direct red, -1, -62, -243; I. Direct blue, -6, -78, -199; I. Direct orange, -34, -60; C.I. I. Direct violet, -47, -48; C.I. I. Direct brown, -109; C.I. I. Direct dyes such as direct green and -59;
C. I. Acid Black, -2, -52, -208; I. Acid Yellow, -11, -29, -71; C.I. I. Acid Red, -1, -52, -317; I. Acid Blue, -9, -93, -254; C.I. I. Acid Orange, -7, -19; C.I. I. Acid violet, acidic dyes such as -49;
C. I. Reactive black, -1, -23, -39; I. Reactive yellow, -2, -77, -163; I. Reactive red, -3, -111, -221; I. Reactive blue, -2, -101, -217; C.I. I. Reactive orange, -5, -74, -99; I. Reactive violet, -1, -24, -38; I. Reactive green, −5, −15, −23; C.I. I. Reactive dyes such as reactive brown, -2, -18, and -33;
C. I. Basic black, -2; I. B. basic red, -1, -12, -27; I. B. basic blue, -1, -24; I. Basic violet, basic dyes such as -7, -14, -27, etc .;
C. I. Food black, food coloring such as -1, and -2; and the like.

  The pigment and the oil-soluble dye can be used by dispersing in an aqueous solution.

  Examples of oil-soluble dyes include azo dyes, methine dyes, azomethine dyes, xanthene dyes, quinone dyes, and phthalocyanine dyes. Specific examples of commercially available dyes are shown below, but the dyes described in the present invention are not limited to the following.

  Examples of black oil-soluble dyes include C.I. I. Solvent Black-3, -22: 1, -50 etc. are mentioned, but it is not limited to these.

  Examples of yellow oil-soluble dyes include C.I. I. Solvent Yellow-1, -25: 1, -172 etc. are mentioned, However, It is not limited to these.

  Examples of orange oil-soluble dyes include C.I. I. Solvent Orange-1, -40: 1, -99 etc. are mentioned, However, It is not limited to these.

  Examples of red oil-soluble dyes include C.I. I. Solvent Red-1, -111, -229, etc. are mentioned, but it is not limited to these.

  Violet oil-soluble dyes include C.I. I. Solvent Violet-2, -11, -47 etc. are mentioned, However, It is not limited to these.

  Examples of blue oil-soluble dyes include C.I. I. Solvent Blue-2, -43, -134 etc. are mentioned, However, It is not limited to these.

  Green oil-soluble dyes include C.I. I. Solvent Green-1, -20, -33 etc. are mentioned, However, It is not limited to these.

  Examples of brown oil-soluble dyes include C.I. I. Solvent Brown-1, -12, -58 etc. are mentioned, However, It is not limited to these.

  Examples of pigments that can be used in the present invention include β-naphthol-based azo pigments, naphthol-AS-based azo pigments, monoazo-type or disazo-type acetoacetyl allylide-type azo pigments, pyrazones-type azo pigments, condensation-type azo pigments, and other azo-type pigments, Phthalocyanine pigments, subphthalocyanine pigments, porphyrin pigments, quinacridone pigments, isoindoline pigments, isoindolinone pigments, selenium pigments, perylene pigments, perinone pigments, thioindigo pigments, dioxazine pigments, quinophthalone pigments And pigments, diketopyrrolopyrrole pigments, and newly synthesized pigments. The pigment used in the present invention is not limited to the above. The following are examples of commercially available pigments for black, cyan, magenta, and yellow.

  Examples of black pigments include Raven 1060 (trade name, manufactured by Columbian Carbon), MOGUL-L (trade name, manufactured by Cabot), Color Black FW1 (trade name, trade name manufactured by Degussa), MA100 (trade name, But not limited to these.

  Examples of cyan pigments include C.I. I. Pigment Blue-15: 3, C.I. I. Pigment Blue-15: 4, C.I. I. Pigment Blue-16, and the like, but are not limited thereto.

  Examples of magenta pigments include C.I. I. Pigment Red-122, C.I. I. Pigment Red-123, C.I. I. Pigment Red-146 and the like, but are not limited thereto.

  Examples of yellow pigments include C.I. I. Pigment Yellow-74, C.I. I. Pigment Yellow-128, C.I. I. Pigment Yellow-129 and the like, but are not limited thereto.

  The coloring material used in the ink composition of the present invention is preferably 0.1 to 50% by mass with respect to the mass of the ink composition. When the amount of the color material is 0.1% by mass or more, a preferable image density is obtained, and when the amount is 50% by mass or less, the color material exhibits a preferable dispersibility. A more preferable range is 0.5 to 30% by mass.

  In addition, although the example of these said coloring material is preferable with respect to the ink composition of this invention, the coloring material used for the ink composition of this invention is not specifically limited to the said coloring material.

[Other ingredients]
Hereinafter, the composition of the present invention will be described in more detail.

  Components other than empty micelles and color materials contained in the composition of the present invention will be described in detail. Other components include aqueous solvents, additives and the like.

[Aqueous solvent]
The composition of the present invention contains an aqueous solvent. The aqueous solvent in the present invention is mainly composed of water, and may contain an organic solvent or an aqueous solvent in addition to water as long as the block polymer compound is dispersed in the state of empty micelle particles. Absent. As water, ion-exchanged water, pure water and ultrapure water from which metal ions and the like have been removed are preferable. Examples of the organic solvent include non-aqueous solvents such as hydrocarbon solvents, aromatic solvents, ether solvents, ketone solvents, ester solvents, amide solvents. Examples of the aqueous solvent include polyhydric alcohols such as ethylene glycol, diethylene glycol, triethylene glycol, polyethylene glycol, propylene glycol, polypropylene glycol, and glycerin; ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol Polyhydric alcohol ethers such as monoethyl ether and diethylene glycol monobutyl ether; nitrogen-containing solvents such as N-methyl-2-pyrrolidone, substituted pyrrolidone and triethanolamine; In addition, monohydric alcohols such as methanol, ethanol and isopropyl alcohol can be used for the purpose of accelerating the drying of the aqueous dispersion on the recording medium.

  In the composition of the present invention, the content of the aqueous solvent is preferably in the range of 10 to 95% by mass with respect to the total mass of the composition. More preferably, it is the range of 20-90 mass%.

[Additive]
Various additives, auxiliaries and the like can be added to the composition of the present invention as necessary. One additive is a dispersion stabilizer that stably disperses a pigment in a solvent. The composition of the present invention has a function of dispersing a particulate solid such as a pigment by a polymer containing a polyvinyl ether structure, but when the dispersion is insufficient, another dispersion stabilizer is added. May be.

  As another dispersion stabilizer, it is possible to use a resin or a surfactant having both hydrophilic and hydrophobic portions. Examples of the resin having both hydrophilic and hydrophobic parts include a copolymer of a hydrophilic monomer and a hydrophobic monomer.

  Examples of the hydrophilic monomer include acrylic acid, methacrylic acid, maleic acid, fumaric acid, or the above carboxylic acid monoesters, vinyl sulfonic acid, styrene sulfonic acid, vinyl alcohol, acrylamide, methacryloxyethyl phosphate, and the like. Examples of the hydrophobic monomer include styrene derivatives such as styrene and α-methylstyrene, vinylcyclohexane, vinylnaphthalene derivatives, acrylic acid esters, and methacrylic acid esters. Copolymers having various configurations such as random, block, and graft copolymers can be used. Of course, both hydrophilic and hydrophobic monomers are not limited to those shown above.

  As the surfactant, an anionic, nonionic, cationic or amphoteric surfactant can be used. Anionic activators include fatty acid salts, alkyl sulfate esters, alkylaryl sulfonates, alkyl diaryl ether disulfonates, dialkyl sulfosuccinates, alkyl phosphates, naphthalene sulfonic acid formalin condensates, polyoxyethylene alkyls. Examples thereof include phosphate ester salts and glycerol borate fatty acid esters. Nonionic activators include polyoxyethylene alkyl ethers, polyoxyethyleneoxypropylene block copolymers, sorbitan fatty acid esters, glycerin fatty acid esters, polyoxyethylene fatty acid esters, polyoxyethylene alkylamines, fluorine-based, silicon-based and the like. It is done. Examples of the cationic activator include alkylamine salts, quaternary ammonium salts, alkylpyridinium salts, alkylimidazolium salts and the like. Examples of amphoteric activators include alkylbetaines, alkylamine oxides, phosphadylcholines, and the like. Similarly, the surfactant is not limited to the above.

  Other additives include, for example, a pH adjuster, a penetrating agent, an antifungal agent, a chelating agent, an antifoaming agent, an antioxidant, an antifungal agent, a viscosity adjusting agent, a conductive agent, and an ultraviolet ray. Absorbers and the like can also be added. The pH adjusting agent is used to obtain stability of ink and stability of ink piping in the recording apparatus. The penetrant accelerates the penetration of the ink into the recording medium and accelerates the apparent drying. The antifungal agent prevents the generation of wrinkles in the ink. The chelating agent sequesters metal ions in the ink and prevents the deposition of metal at the nozzle portion and the insoluble matter in the ink. The antifoaming agent prevents the occurrence of bubbles during the circulation or movement of the recording liquid or during the production of the recording liquid. When various additives are included, care must be taken not to inhibit the uniform dispersion of empty micelle particles.

  In the present invention, by applying an aqueous composition containing the empty micelle particles as a processing liquid after printing on the image surface of a recording medium to which an ink composition containing a color material has been applied, A transparent protective layer made of empty micelle particles can be formed. And the glossiness and abrasion resistance of the recorded image can be improved.

  Further, when used as a self-supporting film without containing a color material, it is possible to form a curtain having a smooth surface state.

  The application of the composition of the present invention to a recording medium can be performed by an ink jet recording method in addition to a known coating method such as a bar coater method or a roll coater method, but is not limited thereto. The ink jet recording method is preferred from the advantages that the coating pattern and the coating amount can be controlled and the printing and post-printing treatment liquid can be continuously applied.

  When the composition of the present invention is used as a treatment liquid, it may be applied to the entire surface of the recording medium to which the composition containing the color material is applied, or may be selectively applied to the portion to which the color material is applied. Also good.

  Next, an image forming method, a liquid applying method and an image forming apparatus using the composition of the present invention will be described.

[Image Forming Method, Liquid Application Method and Apparatus]
The composition of the present invention can be used in various image forming methods and apparatuses such as various printing methods, ink jet methods, and electrophotographic methods, and can be drawn by an image forming method using this device. Moreover, when using a liquid composition, it can be used for the liquid provision method for forming a fine pattern in the inkjet method etc. or administering a medicine.

  The image forming method of the present invention is a method for forming an excellent image with the composition of the present invention. The image forming method of the present invention is preferably an image forming method in which recording is performed by ejecting the composition of the present invention from an ink ejecting portion and applying the composition on a recording medium. For image formation, a method using an ink jet method in which thermal energy is applied to the ink to discharge the ink is preferably used.

  As an ink jet printer using the ink jet composition of the present invention, various ink jet recording apparatuses such as a piezo ink jet method using a piezoelectric element and a bubble jet (registered trademark) method in which heat energy is applied to perform foaming recording are used. Applicable.

  EXAMPLES Hereinafter, although an Example demonstrates this invention in detail, this invention is not limited to these Examples.

(Synthesis Example 1)
<Synthesis of Block Polymer 1> ABCD Type Polymerization was performed as follows by known living cationic polymerization.

  After the inside of the glass container fitted with the three-way cock was replaced with nitrogen, the adsorbed water was removed by heating to 250 ° C. in a nitrogen gas atmosphere. After returning the system to room temperature, 25 mmol (mmol) of 4-methylbenzeneoxyethyl vinyl ether (TolOVE), 160 mmol of ethyl acetate, 0.5 mmol of 1-isobutoxyethyl acetate, and 110 ml of toluene were added, and the reaction system was cooled. When the system temperature reached 0 ° C., 2.0 mmol of ethylaluminum sesquichloride (an equimolar mixture of diethylaluminum chloride and ethylaluminum dichloride) was added to initiate polymerization of the A block. The polymerization reaction was monitored using gel permeation chromatography (GPC) to confirm the completion of polymerization of the A block. At this stage, Mn = 7000 and Mw / Mn = 1.10.

  Next, 25 mmol of 2-vinyloxyethyl methacrylate (VEMA), which is a monomer of the B block, was added, and polymerization was continued. Monitoring using GPC confirmed the completion of polymerization of the B block (Mn at this stage = 14400, Mw / Mn = 1.18). Subsequently, 50 mmol of methoxyethoxyethyl vinyl ether (MOEOVE) which is a monomer of C block was added, and polymerization was continued. Monitoring using GPC confirmed the completion of polymerization of the C block (Mn = 28100 at this stage, Mw / Mn = 1.19). Next, 10 mmol of 4-{(vinyloxy) ethoxy} benzoic acid (t-butyldimethylsilyl) ester (VEEEtPhCOOTBDMSi), which is a monomer of the D block, was added to continue the polymerization. After confirming the completion of polymerization of the D block by monitoring using GPC, the polymerization reaction was stopped. The polymerization reaction was stopped by adding a 0.3% by mass ammonia / methanol aqueous solution to the system. The reaction mixture solution was diluted with dichloromethane and washed 3 times with 0.6M hydrochloric acid and then 3 times with distilled water. The obtained organic phase was concentrated and dried with an evaporator, and the target block polymer was isolated from what was vacuum-dried. The block polymer was identified using NMR and GPC. Mn = 34400, Mw / Mn = 1.17, and the polymerization degree ratio was A: B: C: D = 50: 50: 100: 20.

  Next, 1 g of the obtained block polymer was dissolved in 45 ml of THF, 5 ml of 3N HCl / ethanol solution was added, and the mixture was stirred at room temperature (23 ° C.) for 3 hours, and then 20 ml of ethanol was added and further stirred for 3 hours. The reaction was monitored by NMR. After 100% hydrolysis was completed, the reaction was neutralized with sodium carbonate to complete the reaction. The reaction solution was filtered, concentrated with an evaporator, extracted with methylene chloride and dried, and then the solvent was distilled off to obtain a block polymer in which the side chain of the D block was a free carboxylic acid polymer. Further, it was confirmed by NMR that almost all VEMA double bonds remained.

  Further, neutralization was performed with an equal amount of 1N sodium hydroxide, and water was distilled off to obtain a block polymer 1 in which the side chain of the D block was a sodium carboxylate.

  In the above experimental operation, in order to suppress the reaction of the unsaturated bond of VEMA, concentration by an evaporator and distillation of water were performed at a low temperature of 40 ° C. or less.

(Synthesis Example 2)
<Synthesis of Block Polymer 2> ABC Type A block polymer was synthesized in the same manner as in Synthesis Example 1 except that the addition of the monomer of each block was changed as follows. As a monomer for the A block, ToLOVE 50 mmol and VEMA 50 mmol were added. As a monomer of the B block, 50 mmol of methoxyethoxyethyl vinyl ether (MOEOVE) was added. As a monomer of the C block, 10 mmol of 4-{(vinyloxy) ethoxy} benzoic acid (t-butyldimethylsilyl) ester (VEEtPhCOOTBDMSi) was added. The polymerization of the D block was not performed, and the polymerization reaction was stopped after the polymerization of the C block was completed. Other operations are the same as those in Synthesis Example 1. The block polymer was identified using NMR and GPC. Mn = 43700, Mw / Mn = 1.17, the polymerization degree ratio was A: B: C = 100: 100: 20, and the polymerization degree ratio in the A block was TolOVE: VEMA = 5: 5.

  The obtained block polymer was post-treated in the same manner as in Synthesis Example 1 to obtain a block polymer 2 in which the side chain of the C block was a carboxylic acid sodium salt. Further, it was confirmed by NMR that almost all VEMA double bonds remained.

(Synthesis Example 3)
<Synthesis of block polymer 3>
A block polymer was synthesized in the same manner as in Synthesis Example 1 with the addition of monomers in each block changed as follows. As a monomer of the A block, 35 mmol of TolOVE and 15 mmol of VEMA were added. As a monomer of the B block, a toluene diluted solution of 50 mmol of MOEOVE and 10 mmol of VEEtPhCOOTBDMSi was added. Polymerization of the C and D blocks was not performed, and the polymerization reaction was stopped after completion of the polymerization of the B block. Other operations are the same as those in Synthesis Example 1. The block polymer was identified using NMR and GPC. Mn = 33900, Mw / Mn = 1.19, polymerization degree ratio is A: B = 100: 120, polymerization degree ratio in A block is TolOVE: VEMA = 7: 3, polymerization degree ratio in B block is MOEOVE: VEEEtPhCOOTBDMSi = 5: 1.

  The obtained block polymer was post-treated in the same manner as in Synthesis Example 1 to obtain a block polymer 3 in which the side chain in the B block was a sodium carboxylate. Further, it was confirmed by NMR that almost all VEMA double bonds remained.

(Synthesis Example 4)
<Synthesis of polymer 1 (hydrophobic polymer unit precursor)>
Synthesis of random polymer of 4-methylbenzeneoxyethyl vinyl ether (TolOVE) and 2-vinyloxyethyl methacrylate (VEMA) 4-Methylbenzeneoxyethyl vinyl ether as a monomer by a method similar to the synthesis method of A block in Synthesis Example 1 Polymerization was performed by adding 15 mmol (TolOVE) and 15 mmol of 2-vinyloxyethyl methacrylate (VEMA). Then, the polymerization reaction was stopped after completion of the polymerization. All other conditions are the same as in Synthesis Example 1. By monitoring using GPC, the polymerization reaction was stopped when Mn was 7000. The operation after stopping the reaction was the same as in Synthesis Example 1, and the precursor of the hydrophobic polymer unit as the target product was obtained. The obtained compound was identified using NMR and GPC. Mn = 7000, Mw / Mn = 1.20, and the polymerization degree ratio was TolOVE: VEMA = 1: 1.

(Synthesis Example 5)
Synthesis of block polymer 4 (block polymer having a polymerizable unsaturated group at one end) <Synthesis of polymerization initiation species>
VEMA that had been purified by distillation under reduced pressure under conditions of 45 to 50 ° C./0 mmHg in advance and 10 molar equivalents of acetic acid were mixed and stirred at room temperature for 1 day. The obtained reaction completion liquid was dissolved in hexane and washed with an alkaline aqueous solution to remove unreacted acetic acid. Subsequently, after hexane was distilled off by the obtained solution evaporator, drying under reduced pressure was performed for 1 day or more to obtain a target cation living polymerization initiator (VEM-OAc). The synthesized compound was identified by NMR.

<Synthesis of a block polymer having a polymerizable unsaturated group at one end>
A block: 4-methylbenzeneoxyethyl vinyl ether (TolOVE)
B block: Methoxyethoxyethyl vinyl ether (MOEOVE)
C block: 4-{(vinyloxy) ethoxy} benzoic acid (t-butyldimethylsilyl) ester (VEEtPhCOOTBDMSi)
In the same manner as in Synthesis Example 2, the monomer of the A block is changed to 50 mmol (mmol) of 4-methylbenzeneoxyethyl vinyl ether (TolOVE), and 1-isobutoxyethyl acetate is changed to the previously synthesized VEM-OAc for polymerization. went. The block polymer was identified using NMR and GPC. Mn = 30200, Mw / Mn = 1.24, and the polymerization degree ratio was A: B: C = 100: 100: 20.

  By a post-treatment similar to Synthesis Example 1, a block polymer 4 in which the side chain of the C block was a sodium carboxylate was obtained.

(Example 1)
10 parts by weight of block polymer 1 of Synthesis Example 1 and 0.05 parts by weight of azobisisobutyronitrile (AIBN) are co-dissolved in 200 parts by weight of dimethylformamide, and converted to an aqueous phase using 400 parts by weight of distilled water. A composition was obtained. Furthermore, after dispersing in an ultrasonic homogenizer over 10 minutes, distilled water was added so that the solid content concentration was 1% by mass. During this operation, the operation was performed while cooling the solution so that the temperature was always 40 ° C. or lower. Thereafter, the crosslinking reaction was carried out at a temperature of 60 ° C. for 48 hours.

  Next, a composition in which dimethylformamide was removed with a dialysis membrane (manufactured by SPECTRUM Laboratories, molecular porous membrane tube (MWCO: 3500)) was obtained. Water of this composition was distilled off, and the solid content concentration was adjusted to 20% by mass to obtain an empty micelle particle dispersion.

  Identification of empty micelle particles (particle size, particle size distribution, reaction rate) was carried out by the following procedure.

  Water was added so that the solid content concentration of the empty micelle particle dispersion was 0.01% by mass, and dynamic light scattering (DLS) measurement was performed. As a result, the average particle diameter of the empty micelle particles was 32 nm and the polydispersity degree. The index was 0.11.

  Further, 50 parts by mass of water was added to 5 parts by mass of the above-described empty micelle particle dispersion, and the mixture was stirred uniformly, followed by acid precipitation described below. A 0.1N-HCl aqueous solution was gradually added dropwise to the diluted empty micelle particle dispersion until pH 3, and the resulting precipitate was filtered and washed with water to obtain a transparent resin (acid precipitation). Tetrahydrofuran was added to the transparent resin so that the solid concentration was 0.01% by mass, and dynamic light scattering was measured again. As a result, the average particle size of the empty micelle particles was 35 nm, and the polydispersity index was 0.12. Met. That is, even in a solvent in which all the segments of the block polymer forming the empty micelle particles are soluble, the empty micelle particles do not collapse and maintain a stable empty micelle particle morphology without changing the particle size. Confirmed that.

Further, 50 parts by mass of water was added to 5 parts by mass of the empty micelle particle dispersion and stirred uniformly. Thereafter, 50 parts by mass of heavy water and sodium bihydroxide in an equimolar amount with respect to the ionic group in the polymer were added to the transparent resin obtained by the acid precipitation, and redispersed in an ultrasonic homogenizer over 30 minutes. Thereafter, acid precipitation was carried out again, and in the same manner, heavy water and sodium heavy hydroxide were added and redispersed, and then heavy water was added so that the solid content concentration was 1% by mass. As a result of ¹ H-NMR measurement of this aqueous solution, almost no peaks derived from the hydrophobic segment were observed, only peaks derived from the hydrophilic segment were observed, and it was confirmed that there was a hydrophobic segment in the core part of the empty micelle particle. confirmed. Further, acid precipitation was carried out again, washed thoroughly with water and dried, and deuterated tetrahydrofuran was added so that the solid content concentration was 1% by mass. When ¹ H-NMR and ¹³ C-NMR measurements of this solution were performed, the disappearance of proton and carbon peaks corresponding to the vinyl group was observed, respectively, and it was confirmed that the crosslinking reaction had proceeded.

A composition was prepared so that the resulting empty micelle particle dispersion and the following components had a resin concentration of 10 wt%.
・ Water-based dye (CI Direct Blue 199) 4 parts by mass ・ Empty micelle dispersion 50 parts by mass ・ Ethanol 5 parts by mass ・ Emulgen 120 (trade name, manufactured by Kao Corporation) 0.05 parts by mass Example 2)
A composition of Example 2 having a resin concentration of 10 wt% was obtained in the same manner as in Example 1 except that the block polymer of Synthesis Example 1 was changed to the block polymer 2 of Synthesis Example 2.

  When dynamic light scattering (DLS) measurement was measured in the same manner as in Example 1, the average particle size of the empty micelle particles was 43 nm, and the polydispersity index was 0.09. Also, even in a solvent in which all segments of the block polymer forming the empty micelle particles are soluble, the empty micelle particles do not collapse and maintain a stable empty micelle particle morphology without changing the particle size. Confirmed that. Furthermore, it confirmed that there existed a hydrophobic segment in the core part of empty micelle particle | grains, and the crosslinking reaction advanced.

(Example 3)
A composition of Example 3 having a resin concentration of 10 wt% was obtained in the same manner as in Example 1 except that the block polymer of Synthesis Example 1 was changed to the block polymer 3 of Synthesis Example 3.

  When dynamic light scattering (DLS) measurement was performed in the same manner as in Example 1, the average particle size of the empty micelle particles was 33 nm and the polydispersity index was 0.10. Also, even in a solvent in which all segments of the block polymer forming the empty micelle particles are soluble, the empty micelle particles do not collapse and maintain a stable empty micelle particle morphology without changing the particle size. Confirmed that. Furthermore, it confirmed that there existed a hydrophobic segment in the core part of empty micelle particle | grains, and the crosslinking reaction advanced.

Example 4
Example 1 except that 1 part by weight of the polymer 1 which is the hydrophobic polymer unit precursor of Synthesis Example 4 and 10 parts by weight of the block polymer 4 of Synthesis Example 5 were used, and the crosslinking reaction was performed at a temperature of 80 ° C. for 48 hours. The composition used as Example 4 whose resin concentration is 10 wt% was obtained by the same method.

  When dynamic light scattering (DLS) measurement was performed in the same manner as in Example 1, the average particle size of the empty micelle particles was 38 nm, and the polydispersity index was 0.08. Also, even in a solvent in which all segments of the block polymer forming the empty micelle particles are soluble, the empty micelle particles do not collapse and maintain a stable empty micelle particle morphology without changing the particle size. Confirmed that. Furthermore, it confirmed that there existed a hydrophobic segment in the core part of empty micelle particle | grains, and the crosslinking reaction advanced.

(Comparative Example 1)
The empty micelle particle dispersion of Example 1 was changed to water-soluble polyvinyl alcohol (polymerization degree: 500, saponification degree: 90%), and other components were made the same as in Example 1 to obtain a resin concentration of 10 wt%. A composition to be Comparative Example 1 was obtained.

(Comparative Example 2)
The empty micelle dispersion of Example 1 was changed to commercially available polymer fine particles (trade name: E2500, manufactured by Daiichi Kogyo Seiyaku Co., Ltd., particle size 250 nm, polydispersity index 1.00), and other components were the same as in Example 1. Thus, a composition serving as Comparative Example 2 having a resin concentration of 10 wt% was obtained.

[Composition evaluation]
(1) Dispersion stability and viscosity evaluation The compositions obtained in Examples 1 to 4 and Comparative Examples 1 and 2 were allowed to stand at room temperature for 3 days and then visually observed. A sediment was observed.

  In addition, the water-soluble composition using an additive resin is usually used at 5% or less because of viscosity. Therefore, this evaluation is deliberately examined with a resin amount higher than the normal use conditions.

  Next, the viscosities of the compositions obtained in Examples 1 to 4 and Comparative Examples 1 and 2 after standing were measured with an E-type viscometer.

  In general, when the viscosity of the water-soluble composition exceeds 20 cps, it may be difficult to apply in an ink-jet application or cause coating unevenness, which is not preferable. When the viscosities of the compositions obtained in Examples 1 to 4 and Comparative Examples 1 and 2 were measured, the compositions of Examples 1 to 4 and Comparative Example 2 were both less than 20 cps in viscosity. As for Comparative Example 1, it was confirmed that the liquid had a high viscosity exceeding 40 cps.

  As described above, it was confirmed that the compositions of Examples 1 to 4 of the present application had good dispersion stability and hardly increased viscosity even when the amount of the resin was relatively high.

(2) Ejection Evaluation Next, in order to determine whether the composition of Examples 1 to 4 of the present application can be used in an inkjet head, the composition obtained in Examples 1 to 4 was used as an inkjet printer (trade name: PX -G900 (manufactured by Seiko Epson Corporation) was filled into a print head, and a discharge test was performed. In the ejection test, a solid image of 5 cm × 5 cm was used using a glossy ink jet paper having a surface average pore diameter of 20 nm or less having a void in the outermost layer of the ink receiving layer (main components: silica and polyvinyl alcohol) as a recording medium. It was performed by forming on a recording medium.

  All of the compositions obtained in Examples 1 to 4 were ejected satisfactorily, and desired recorded images were obtained.

  Next, the recording medium was cut at the recorded image portion obtained from the compositions of Examples 1 to 4, and the cut surface of the image was observed with an optical microscope and an electron microscope. The dye penetrated into the recording medium. It was confirmed that a polymer layer was formed on the outermost surface of the recording medium. That is, according to the compositions of Examples 1 to 4, images overcoated with the polymer layer were obtained.

[Self-standing film test]
Next, in order to confirm the surface properties when the compositions of Examples 1 to 4 are used as a self-supporting film, the empty micelles of Examples 1 to 4 have a wet film thickness of 2.23 μm on a glass substrate. A self-supporting film was obtained by applying the dispersion. For coating, ROD No. 2 Mayer bars (R.D. Specialties, USA) were used. When the smoothness of the obtained free-standing film was observed using an atomic force microscope (AFM), the empty micelle dispersions of Examples 1 to 4 were not sufficiently obtained with polymer fine particles such as latex particles, and were sufficiently smooth. It was confirmed that the surface state.

  From the above results, the empty micelle particle-containing composition according to the present invention is a composition suitable for inkjet ejection, in which the viscosity of the solution does not increase even when the amount of resin contained is high, Penetration into a recording medium such as glossy paper can also be suppressed.

  In addition, since the self-supporting film obtained by the above composition has a smooth surface structure without graininess compared to a general latex particle-containing composition, the functions such as gloss can be improved by combining color materials. Can be expected.

  In addition, although the said evaluation was confirmed in the example which used dye as a coloring material, even if it is a case where a pigment is used, there can exist the same effect. Furthermore, when using as a self-supporting film, it goes without saying that an excellent effect can be obtained by using the composition without containing a colorant.

It is a schematic diagram which shows the composition of this invention, and has shown the state in which the empty micelle particle | grains which consist of a resin dispersion which the empty micelle or several of the empty micelles couple | bonded are melt | dissolved or disperse | distributed in the aqueous solvent. It is a schematic diagram which shows the empty micelle of this invention, and has shown the state which the empty micelle has bridge | crosslinked in a micelle. When the ink composition of the present invention is applied to a recording medium, the coloring material penetrates into the recording medium, and empty micelle particles remain on the recording medium to form a film, thereby forming a protective layer on the image surface. It is a schematic diagram which shows forming.

Explanation of symbols

10: Block polymer compound 11: Hydrophobic block segment 12: Hydrophilic block segment 20: Color material (dye)
30: Cross-linked portion 40: Dispersion (microsphere-like)
40 ': Dispersion (a collection of several dispersions 40)
50: Recording medium 51: Gaps existing on the surface of the recording medium 60: Aqueous solvent

Claims (19)

A composition comprising a block polymer compound having at least a hydrophilic block segment and a hydrophobic block segment and having a crosslinkable functional group, and an aqueous solvent,
The block polymer compound exists as a resin dispersion in which a micellar state is formed only with the block polymer compound in which the hydrophobic block segment is arranged in the core in the aqueous solvent, and the block polymer compound has the crosslinkable functional group. A composition having a crosslinked structure crosslinked with a group.   The composition according to claim 1, wherein the resin dispersion has an average particle size of 500 nm or less and a polydispersity index of 1 or less.   The composition according to claim 1 or 2, wherein the crosslinked structure is formed only in the core part.   The composition according to claim 3, wherein the block polymer compound has a crosslinkable functional group only in the hydrophobic block segment.   The composition according to claim 1, wherein the crosslinkable functional group is a self-crosslinkable functional group.   6. The composition according to claim 5, wherein the self-crosslinkable functional group is a radical polymerization unsaturated group or a hydrolyzable alkoxysilane group.   The composition according to any one of claims 1 to 4, further comprising a crosslinking agent that causes a crosslinking reaction of the crosslinkable functional group.   The composition according to any one of claims 1 to 7, wherein the block polymer compound comprises an ionic hydrophilic block segment and a nonionic hydrophilic block segment as the hydrophilic block segment.   The composition according to claim 8, wherein the block polymer compound is bonded in the order of the hydrophobic block segment, the nonionic hydrophilic block segment, and the ionic hydrophilic block segment.   The composition according to any one of claims 1 to 9, wherein the main chain structure of each block segment of the block polymer compound is a polyalkenyl ether structure.   The method for producing a composition according to any one of claims 1 to 10, wherein the dispersion forms a resin dispersion in which a core portion is formed by aggregation of hydrophobic block segments of the block polymer compound in the aqueous solvent. And a method for producing a composition comprising at least a crosslinking step for crosslinking the block polymer compound.   An ink composition comprising at least a colorant and the composition according to any one of claims 1 to 10.   The ink composition according to claim 12, wherein the coloring material is a dye.   A method for producing the ink composition according to claim 12 or 13, wherein at least the step of dissolving or dispersing the coloring material, the obtained solution or dispersion, and the composition according to any one of claims 1 to 10. And a step of mixing the product with the product.   14. An image forming method for applying an ink composition according to claim 12 or 13 to a recording medium, wherein the resin dispersion remains on the recording medium, and the coloring material penetrates into the recording medium. An image forming method characterized in that image formation is performed.   An image comprising applying an ink composition containing a colorant to a recording medium to form an image, and then applying the composition according to any one of claims 1 to 10 on the image. Forming method. The image forming method according to claim 15 or 16, wherein the average particle diameter of the resin dispersion and the average surface pore diameter of the recording medium satisfy the following relational expression (A).
[Average particle diameter of resin dispersion] − [Average surface pore diameter of recording medium] ≧ 1 nm (A)   The image forming method according to claim 15, wherein an average particle size of the resin dispersion is 20 nm or more.   The image forming method according to claim 15, wherein a polydispersity index of the resin dispersion is 0.3 or less.

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