JP2013193324A - Image recording method and image recording object - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image recording method which has excellent adhesion to a recording base material with an ink non-absorption property or a low absorption property and obtains an image with excellent scratch resistance.SOLUTION: An image recording method has an ink imparting step to impart an ink composition containing a colorant, a polymer particle A comprising a polyolefin component and treated by modification selected from chlorination modification, acrylic modification and maleic anhydride modification and a polymer particle B having a structural part different from the polymer particle A on a recording base material of an aggregate of a fiber material with a non-absorption property or a low absorption property by an inkjet method.

Description

  The present invention relates to an image recording method and an image recorded matter.

  In recent years, there are a wide variety of methods for recording images, and any method is required to obtain a high-quality image. For example, a conventional printing method or an inkjet method that has been attracting attention in recent years can be used.

  Among these, as an image recording method using an inkjet method, a method is known in which recording is performed by ejecting ink in a droplet form from a large number of nozzles provided in an inkjet head. This method is widely used because it can form an image at high speed and can record a high-quality image on a wide variety of recording media.

  A pigment is widely used as a colorant which is one of the components of the ink material, and the pigment is used by being dispersed in a medium such as water. When pigments are used in a dispersed manner, the dispersed particle size when dispersed, stability after dispersion, size uniformity, ejection properties from the ejection head, and image density are important. There are various ways.

On the other hand, when an image is recorded by the ink jet method, the durability of the recorded image is one of the important properties from the viewpoint of quality, and the properties that affect the durability include, for example, resistance to image abrasion and adhesion. Sex.
Various attempts have been made to improve the scratch resistance, which is one of the indicators of image durability. For example, an inkjet recording ink containing an aqueous resin emulsion in the ink for the purpose of solidifying the ink film is disclosed (for example, see Patent Document 1). Furthermore, it is known to use wax particles with the aim of improving the slipperiness of the image and improving the apparent abrasion resistance. For example, a printing method in which ink jet recording is performed on a non-ink-absorbing or low-absorbing recording medium using a resin ink containing resin particles and wax particles together with color ink has been attempted (for example, see Patent Document 2). It is said to be excellent in image quality and abrasion resistance regardless of the ink absorbability of the recording medium.

  In addition, adhesion to ink is also a property related to durability. In order to improve this adhesion, it is also widely known to perform a pretreatment on a base material. For example, an example in which a surface treatment such as a corona treatment is performed on a nonwoven fiber web is disclosed (for example, Patent Documents). 3). However, when surface treatment such as corona treatment is performed, the quality of the recorded material often deteriorates due to the rough surface of the substrate.

  On the other hand, as an ink composition for printing with improved adhesion to a plastic film, a composition containing a binder for printing ink composed of a chlorinated polyolefin of a modified polyolefin obtained by reaction of a specific component and a urethane resin, or a maleic anhydride-modified polypropylene system Compositions containing an aqueous binder resin varnish and an aqueous acrylic resin varnish have been proposed (see, for example, Patent Documents 4 to 5).

JP 2006-249203 A JP 2010-105187 A Special table 2011-513049 gazette JP-A-8-12913 JP-A-9-31386

  When a non-absorbent or low-absorbent synthetic fiber such as polypropylene is used as a recording medium and an ink image is formed on these, such a fiber itself does not absorb ink, and it is microscopically an image. Since the surface on which the ink is formed is not a flat continuous surface, it is difficult to fix the ink to the substrate. For this reason, a phenomenon such as peeling or dropping due to scratching or rubbing is likely to occur, and image quality is liable to be impaired, such as inferior image scratch resistance.

  Among the above conventional techniques, in the ink for ink jet recording using the aqueous resin emulsion, the image is formed including polymer particles. However, the non-absorbing or low-absorbing recording medium (nonwoven fabric) as described above is used. Etc.) is not necessarily satisfied in terms of scratch resistance. The recording media as described above are generally known to have poor adhesion to ink, and sufficient ink rub resistance cannot always be obtained simply by including polymer particles and wax particles in the ink. .

  In addition, although it has been attempted to use a plurality of resin components in printing ink from the viewpoint of adhesiveness, when forming an image on a non-absorbent or low-absorbent substrate, and consequently a fiber assembly such as a non-woven fabric by an inkjet method It cannot be expected to have high scratch resistance and close contact that are required for the use.

  The present invention has been made in view of the above, and is excellent in adhesion with an aggregate of non-ink-absorbing or low-absorbing fiber materials (such as nonwoven fabric formed of resin fibers) and scratch resistance. It is an object of the present invention to provide an image recording method for obtaining an image and an image recording material having an image excellent in scratch resistance and adhesion to a recording substrate, and to achieve the object.

  In the present invention, when recording an image using a non-absorbent or low-absorbent non-absorbent fiber such as polypropylene as a recording base material, such a base material may be a plain paper or inkjet used for normal image recording. Compared to special paper, etc., not only ink absorbency but also contact with ink, and hence poor adhesion, so the composition contains polymer particles in the ink, and some of the particles have a polyolefin structure and a specific modifying group Then, in comparison with the conventional combination mode of the ink and the recording medium, the knowledge that the adhesion to the substrate such as the nonwoven fabric and the scratch resistance of the image is drastically improved was obtained, and the achievement was achieved based on such knowledge. Is.

Specific means for achieving the above object are as follows.
<1> Polymer particle A containing a colorant and a polyolefin component, and having undergone a modification treatment selected from chlorination modification, acrylic modification, and maleic anhydride modification, and polymer particle B having a different structure from the polymer particle A Is an image recording method including an ink application process in which an ink composition containing the above is applied to a recording base material, which is an aggregate of non-absorbent or low-absorbent fiber materials, by an inkjet method.
<2> The image recording method according to <1>, wherein the polymer particle B has a polymer structure excluding a polyolefin structure as a polymer skeleton.
<3> The image recording method according to <1> or <2>, wherein the polymer particle B is a resin particle selected from an acrylic resin, a urethane resin, an ester resin, and a styrene resin. .
<4> The above <1> to <3>, wherein the content ratio (A: B) of the polymer particles A and the polymer particles B is in the range of 0.1: 9.9 to 3: 7 in terms of mass ratio. The image recording method according to any one of the above.
<5> The image recording method according to any one of <1> to <4>, wherein the ink composition further contains wax particles having a melting point of 50 ° C. or higher and 150 ° C. or lower.
<6> The image recording method according to any one of <1> to <5>, wherein the glass transition point of the polymer particle B is 5 ° C. or more and 60 ° C. or less.

<7> The image recording method according to any one of <1> to <6>, wherein the polymer particle A has a weight average molecular weight of 3000 or more.
<8> The image recording according to any one of <1> to <7>, wherein the ink application step applies the ink composition to the recording substrate with an ink droplet amount of 60 pl to 120 pl. Is the method.
<9> The image according to any one of <1> to <8>, further including a dry fixing step of drying and fixing the ink composition applied in the ink applying step to the recording substrate. It is a recording method.
<10> A pretreatment step of performing a pretreatment selected from the group consisting of corona treatment, plasma treatment, flame treatment, heat treatment, wear treatment, and light irradiation treatment on the recording substrate before the ink application step. The image recording method according to any one of <1> to <9>.
<11> The image recording method according to any one of <5> to <10>, wherein the wax particles have a weight average molecular weight or a molecular weight of less than 3000.
<12> The above <1> to <11>, wherein the total amount of the polymer particles A and the polymer particles B is 0.1% to 20% by mass ratio with respect to the total amount of the ink composition. The image recording method according to any one of the above.

<13> A polymer a containing a recording base material that is an aggregate of non-absorbing or low-absorbing fiber materials, a polyolefin component, and subjected to a modification treatment selected from chlorination modification, acrylic modification, and maleic anhydride modification And a polymer b having a different structure from the polymer a, and an ink image containing a colorant.
<14> The image-recorded material according to <13>, wherein the polymer b has a polymer skeleton excluding a polyolefin skeleton.
<15> The image recorded matter according to <13> or <14>, wherein the polymer b includes a resin component selected from an acrylic resin, a urethane resin, an ester resin, and a styrene resin.

According to the present invention, an image recording capable of obtaining an image excellent in adhesiveness and scratch resistance with an aggregate of non-ink-absorbing or low-absorbing fiber materials (such as a nonwoven fabric formed of resin fibers). A method is provided. Also,
According to the present invention, an image recorded matter having an image excellent in scratch resistance and adhesion to a recording substrate is provided.

(A) is a conceptual diagram conceptually showing the spread of the ink and the adhesion to the fiber when the ink is ejected onto the nonwoven fabric, and (B) is the ink when the ink is ejected onto the recording paper. It is a conceptual diagram which shows notionally spreading.

  Hereinafter, the image recording method of the present invention and the image recorded matter obtained thereby will be described in detail.

<Image recording method>
The image recording method of the present invention comprises a polymer particle A containing a colorant and a polyolefin component and subjected to a modification treatment selected from chlorination modification, acrylic modification and maleic anhydride modification, and a structural part different from the polymer particle A And an ink application step of applying an aqueous ink containing polymer particles B having a non-absorbent or low-absorbent recording base material. In addition, the image recording method of the present invention can be preferably configured by providing a dry fixing step for drying and fixing the water-based ink applied in the ink applying step, and further includes other steps as necessary. May be.

In the present invention, it is not a recording paper mainly composed of pulp, such as plain paper, ink jet exclusive paper, coated paper and the like, which are generally used for ink jet recording, but is non-ink-absorbing or low-absorbing, such as polypropylene and polyethylene. When image recording is performed using a nonwoven fabric or the like formed of fibers as a recording base material, the applied ink is a polymer particle A having a polyolefin structure and subjected to a predetermined modification treatment. By containing together with the polymer particles, the polyolefin structure and the modifying group in the polymer constituting the polymer particles act on the recording substrate and other polymer particles, respectively, and the adhesion between the image and the substrate is enhanced. It is guessed. That is, such an effect is not only poor in ink absorbability but also given between the fiber assembly having a small contact area with the ink droplet and the ink, so that the entire formed image is, for example, plain paper or film This improves the adhesion and scratch resistance of images in a recording system that does not share one recording surface (that is, does not contact with a continuous surface). As a result, compared to the conventional combination mode of ink and recording substrate, the scratch resistance of an image that is significantly weaker than that recorded on plain paper or the like is further improved, and ink that is generally considered to have poor adhesion with water-based ink Adhesiveness with a non-absorbing or low-absorbing recording substrate is also improved. Such an improvement effect on the scratch resistance and adhesion is particularly prominent in the case of a recording system in which the amount of ink droplets is a relatively large droplet amount of 60 pl (picoliter; the same applies hereinafter) or more.
In the past, attempts have been made to increase the strength of the image by including polymer particles in the ink, but in addition to non-absorbing or low-absorbing ink, a fiber material that has a small ink landing area and is difficult to deposit stably is used. In a recording system for recording an image on a conventional substrate, desired adhesion and scratch resistance cannot be ensured by simply adding polymer particles. From this point, the composition containing polymer particles A having a polyolefin structure and a predetermined modifying group together with other polymer particles structurally different from the polymer particles is a recording base material using a fiber material having poor ink absorbability. It is considered that the technical effect exerted in the recording application is large.
Further, in the present invention, texture such as a feeling of touch of an image (for example, softness of an image and little stickiness) can be enhanced, which is useful for forming a high-quality image.

[Ink application process]
The ink application process in the present invention includes a polymer particle A containing a colorant and a polyolefin component and subjected to a modification treatment selected from chlorination modification, acrylic modification, and maleic anhydride modification, and a structural portion different from the polymer particle A The ink composition containing the polymer particles B having the above is applied onto a recording substrate which is an aggregate of non-absorbing or low-absorbing fiber materials by an ink jet method. The application of the ink composition can be performed by selecting from any method for recording an image by applying ink to a recording substrate. Among them, the method using the inkjet method is preferable because a plate is not required and the cost can be kept low even in small-lot printing, and printing can be performed on a fibrous base material having an uneven surface. It is. Details of the ink composition in the present invention will be described later.

The application of the water-based ink to the recording substrate can be suitably performed by an ink jet method. In the ink jet method, ink is selectively applied to a desired region.
The ink jet method is not particularly limited, and is a known method, for example, a charge control method for discharging ink using electrostatic attraction, a drop-on-demand method (pressure pulse method) using vibration pressure of a piezo element, An acoustic ink jet system that converts an electrical signal into an acoustic beam, irradiates the ink with ink, and ejects the ink using radiation pressure, and a thermal ink jet that forms bubbles by heating the ink and uses the generated pressure (bubble jet (registered) Trademark)) method or the like.

  When ink is applied to the recording substrate by the ink jet method, the application method may be multipass or single pass, but from the viewpoint of high speed recording, one pass or two passes is preferable. Here, one pass refers to a recording method in which all the dots to be formed in the scanning region are recorded in one scan in the main scanning direction, and the width in the substrate width direction intersecting the sub-scanning direction at the time of recording. An ejection head having a length corresponding to the length (line head in which recording elements are arranged) is provided, and ink is ejected simultaneously in the main scanning direction from a plurality of ejection holes provided in the ejection head. This is called a so-called line method, and an image can be recorded on the entire surface of the recording substrate by scanning the recording medium in a direction (sub-scanning direction) intersecting the arrangement direction of the recording elements. There is no need for a carriage system such as a shuttle system that records while scanning a short serial head in the width direction (main scanning direction) of the recording substrate. In addition, the two passes are a method of recording dots to be ejected to the scanning area by performing two scans.

The amount of ink droplets applied to the recording substrate is not particularly limited as long as it satisfies the required scratch resistance, adhesion, and, if necessary, the texture of the image area. An arbitrary drop amount may be selected in consideration of the type of image and image density.
In the present invention, the amount of ink droplets is in the range of 60 pl or more and 120 pl or less particularly in that the scratch resistance and adhesion of an image recorded on a non-absorbing or low-absorbing recording substrate can be more effectively enhanced. Is preferred. Among these, for the same reason, the ink droplet amount is more preferably in the range of 70 pl to 110 pl, and further preferably in the range of 70 pl to 100 pl. When the amount of ink droplets is 60 pl or more, an ink region is secured after fixing and is not easily peeled off, the adhesion of the image to the substrate is improved, and the scratch resistance is further improved. Further, when the ink droplet amount is 120 pl or less, the drying of the droplets on the substrate surface can be maintained satisfactorily, and the occurrence of image bleeding is prevented.

  The diameter of the ink droplets applied to the recording substrate (the diameter before landing) is preferably 48 μm to 61 μm, and more preferably 51 μm to 59 μm. The diameter of the ink droplet can be directly measured by droplet observation with a high speed camera (for example, Hyper Vision HPV-2A manufactured by Shimadzu Corporation).

  The viscosity (30 ° C.) of the water-based ink is preferably 4 to 20 mPa · s, more preferably 6 to 16 mPa · s, from the viewpoint of stably supplying ink from the ink tank to the recording head.

  For example, the resolution per color is preferably 100 dpi (dot per inch) or more, and the ink viscosity is preferably 4 to 20 mPa · s (30 ° C.). The resolution is preferably 200 dpi or more from the viewpoint of high image quality.

In the present invention, a water-based ink composition is used in that it does not impair the global environment or the working environment during image recording. A water-based ink composition generally has poor absorbency to non-woven fabrics formed of non-ink-absorbing or low-absorbing fibers, and it is difficult to obtain close contact. Ink in the present invention is polymer particles A as described above. And polymer particles B, an image having good adhesion and excellent scratch resistance can be obtained.
As an example, the image forming property in the case of forming an image by ejecting ink onto a nonwoven fabric by an ink jet method will be described in comparison with a sheet paper. When ink is applied to a nonwoven fabric that is an aggregate of fibers such as polypropylene, the ink is absorbed into the nonwoven fabric, but the fibers themselves forming the nonwoven fabric are poor in ink absorbability, and are shown in FIG. In this way, some of the ink droplets 11 that have landed adhere to the fiber and remain on the fiber surface to form a colored portion, but the amount of droplet that cannot be adhered and retained separates and further penetrates into the deep part of the material. . On the other hand, in a sheet paper (plain paper or the like) that is widely used for ink jet recording in general, since the material itself such as pulp forming the sheet absorbs ink, the applied ink is as shown in FIG. In addition, after landing on the sheet surface, it spreads not only in the thickness direction of the sheet but also in the surface direction, and enters the space portion in the paper, so that it is easily fixed. In other words, in the non-woven fabric, the ink is present on the fiber surface with poor absorbency as shown in FIG. 1A, but is not absorbed. Therefore, the ink droplet is fixed at the landing position unless it acts on the fiber surface within the narrow area. There is a tendency that it is difficult to become. In the present invention, polymer particles are included in the ink, but a polyolefin structure and a modifying group are given to a part of the polymer particles so that a bridging function between the other polymer particles and the substrate is developed. In particular, when a fiber material such as polypropylene fiber is used, adhesion between the polymer particles in the ink and the fiber assembly is assisted. This also improves the scratch resistance of the image.

-Water-based ink-
The ink composition according to the present invention is a polymer particle containing water and comprising a colorant and a polyolefin component and subjected to a modification treatment selected from chlorination modification, acrylic modification, and maleic anhydride modification. It is comprised in the composition containing A and the polymer particle B which has a structural part different from this polymer particle A at least. The ink composition of the present invention can be further constituted using components such as a pigment dispersant, wax, an organic solvent, a surfactant, and other additives as necessary.

(Polymer particles)
The ink composition in the present invention contains at least two kinds of polymer particles, specifically, includes a polyolefin component, and is subjected to a modification treatment selected from chlorination modification, acrylic modification, and maleic anhydride modification. Polymer particles A and polymer particles B having a different structure from the polymer particles A are included. By containing a plurality of polymer particles including polymer particles A and B, the adhesion of the image to the recording substrate and the scratch resistance are improved.

~ Polymer particles A ~
The polymer particle A in the present invention is not particularly limited except that it contains a polyolefin component and is subjected to a modification treatment selected from chlorination modification, acrylic modification, and maleic anhydride modification.

  The polyolefin component contained in the polymer particles A is a polymer of olefins such as ethylene, propylene, and butylene, and includes, for example, polyethylene and polypropylene.

  The inclusion of a polyolefin component means that the polymer has a polyolefin structure. The polymer (hereinafter, also referred to as polymer a) constituting the polymer particle A preferably has a polyolefin structure (particularly, a polyethylene chain or a polypropylene chain) as a main chain in the molecule.

  The modified polymer constituting the polymer particle A can be obtained by applying a modifying group to the polymer by a known method to give a modifying group. The modified polymer may be subjected to any modification treatment of chlorination modification, acrylic modification, and maleic anhydride modification, or a plurality of modification treatments selected from chlorination modification, acrylic modification, and maleic anhydride modification. Alternatively, one or more of the modification treatments and other modification treatments other than these may be applied. The polymer of the polymer particles A may be, for example, a polymer modified with maleic anhydride and chlorinated.

  The chlorinated polymer particles include particles such as chlorinated modified polyolefin resin, and examples thereof include particles such as chlorinated modified polyethylene and chlorinated modified polypropylene.

  The acrylic-modified polymer particles include particles such as acrylic-modified polyolefin resin and acrylic-modified polyolefin-modified resin. Examples of the acrylic modified polymer particles include particles such as acrylic modified polyethylene and acrylic modified polypropylene, and particles such as acrylic modified chlorinated polyethylene resin and acrylic modified chlorinated polypropylene resin.

  The maleic anhydride-modified polymer particles include particles such as maleic anhydride-modified polyolefin resin and maleic anhydride-modified polyolefin modified resin. For example, maleic anhydride-modified polyethylene, maleic anhydride-modified polypropylene, maleic anhydride Examples thereof include particles such as acid-modified / chlorinated modified polyethylene and maleic anhydride-modified / chlorinated modified polypropylene.

  As the polymer particles A, commercially available products may be used. As an example of a commercially available product, Super Clon series manufactured by Nippon Paper Chemicals Co., Ltd. (Example: Super Clon E-415 (maleic anhydride modified / chlorinated modified)) E723 (chlorination modification), etc.), Aurolen series (non-chlorinated polyolefins, manufactured by Nippon Paper Chemicals Co., Ltd., for example: Aurolen AE-301 (maleic anhydride / acrylic modification), S-6375 (maleic anhydride) Acrylic modified), etc.), Hardylene NA-3002 (maleic anhydride modified) manufactured by Toyobo Co., Ltd., NZ-1001, etc., and the Syxen series manufactured by Sumitomo Seika Co., Ltd. (example: Zyxen L (acrylic modified), A, NC, N, etc.).

The weight average molecular weight of the polymer a forming the polymer particle A is preferably 3000 or more. When the weight average molecular weight is 3000 or more, there is an advantage that the adhesion of the ink to the recording substrate is improved. The weight average molecular weight is more preferably 30,000 or more, still more preferably 50,000 or more, still more preferably 60,000 or more and 120,000 or less, and particularly preferably 80,000 or more and 100,000 or less. It is.
The weight average molecular weight is measured by gel permeation chromatography (GPC). GPC uses high-speed GPC (Gel Permeation Chromatography) HLC-8220GPC (manufactured by Tosoh Corporation), and TSKgeL Super HZM-H, TSKgeL Super HZ4000, TSKgeL Super HZ2000 (Tosoh Corporation), 4. Three (6 mm ID × 15 cm) are used, and THF (tetrahydrofuran) is used as an eluent. Details of GPC are described in paragraph number [0076] of Japanese Patent Application Laid-Open No. 2010-155359.

  The melting point (Tm) of the polymer a is preferably in the range of 50 ° C. or higher and 100 ° C. or lower, more preferably 60 ° C. or higher and 90 ° C. or lower, and further preferably 60 ° C. or higher and 80 ° C. or lower. When Tm is 50 ° C. or higher, it is advantageous in terms of adhesion of the ink on the recording substrate, and when Tm is 100 ° C. or lower, in terms of fixability of the ink on the recording substrate. It is advantageous.

  The content of the polymer particles A in the ink composition is preferably 0.1 to 6% by mass and more preferably 0.1 to 3% by mass with respect to the total amount of the ink composition. When the content of the polymer particles A is 0.1% by mass or more, the image adhesion is further improved, and the scratch resistance is more excellent. Further, when the content of the polymer particles A is 6% by mass or less, the viscosity of the ink composition can be maintained in a range suitable for ejection, and the ejection stability and maintainability can be favorably maintained. Two or more kinds of polymer particles A may be used in combination, or particles composed of a polymer in which two or more kinds are mixed or bonded may be used.

~ Polymer particles B ~
The ink composition contains, together with the polymer particles A, at least one kind of polymer particles B having a structural portion different from the polymer particles A. As the polymer particle B in the present invention, a polymer particle having a structure different from the polymer structure of the polymer particle A is used from the viewpoint that the polymer particle A functions as a bridge between the polymer particle B and the recording substrate. The main chain skeleton is composed of a polymer structure other than the polyolefin structure. By containing the polymer particles B together with the polymer particles A, the scratch resistance and adhesion of the image are further improved.

  The “structure portion different from the polymer particle A” in the polymer particle B is a polymer in the polymer constituting the polymer particle B (hereinafter also referred to as polymer b) in terms of a polymer molecular structure such as a main chain, a side chain, or a modifying group. It means that a structure different from the polymer a of the particle A exists. The polymer b may be a polyolefin-based resin as long as there is a difference from the polymer a due to a different modified structure or the like, and when the polymer b does not have a polyolefin skeleton, it may be subjected to a modification treatment in the same manner as the polymer a.

  The polymer b of the polymer particle B can be selected from particles of any polymer as long as it has a different structural portion from the polymer a of the polymer particle A. Examples of polymer particles B include chlorinated, acrylic-modified, or maleic anhydride-modified polymer particles that do not include a polyolefin structure as the main chain skeleton but include other polymer structures other than polyolefin, or the modification that includes a polyolefin component. It may be a polymer particle that has not been treated.

  Examples of the polymer b constituting the polymer particle B include thermoplastic, thermosetting, or modified acrylic resins, epoxy resins, urethane resins, polyether resins, polyamide resins, and unsaturated polyester resins. , Phenolic resin, silicone resin, fluorine resin, polyvinyl resin (eg, vinyl chloride, vinyl acetate, polyvinyl alcohol, or polyvinyl butyral), alkyd resin, polyester resin (eg, phthalic acid resin), amino Examples thereof include resins such as system materials (for example, melamine resin, melamine formaldehyde resin, aminoalkyd cocondensation resin, urea resin, urea resin, etc.) or copolymers or mixtures thereof. Among them, the polymer b is preferably an acrylic resin, a urethane resin, an ester resin, or a styrene resin from the viewpoint of further improving the adhesion and scratch resistance of the image, and particularly preferably a urethane resin from the following viewpoints.

The reason why the urethane-based resin is preferable is estimated as follows. That is,
Urethane resin is made up of urethane sites that allow strong interactions such as hydrogen bonding between polymers and non-urethane sites that have relatively weak interactions between polymers, forming an ink film. As a micro structure, it is estimated that a relatively strong interaction part and a relatively weak interaction part gather together to construct a sea-island structure, which makes polyurethane flexible. It is estimated to be. Since polyurethane is inherently flexible in this way, it is possible to use one having a high Tg, as compared to the conventional example using low Tg polymer particles, and the flexibility and strength are improved. It is presumed that an ink film (ink image) having excellent scratch resistance can be formed.
Therefore, it is particularly advantageous when a “recording substrate that is an aggregate of non-absorbent or low-absorbent fiber materials” that is difficult to obtain scratch resistance.

  Moreover, as said acrylic resin, what has an anionic group is preferable. Such an acrylic resin includes, for example, an acrylic monomer having an anionic group (anionic group-containing acrylic monomer) and, if necessary, another monomer copolymerizable with the anionic group-containing acrylic monomer in a solvent. Obtained by polymerization. Examples of the anionic group-containing acrylic monomer include an acrylic monomer having one or more selected from a carboxyl group, a sulfonic acid group, and a phosphonic group. Among them, an acrylic monomer having a carboxyl group (for example, acrylic acid, methacrylic acid, Crotonic acid, ethacrylic acid, propylacrylic acid, isopropylacrylic acid, itaconic acid, fumaric acid, etc.) are preferred, and acrylic acid or methacrylic acid is particularly preferred.

As the polymer particles B, self-dispersing polymer particles having self-dispersibility can be suitably used. When the self-dispersing polymer particles are in a dispersed state (particularly, a dispersed state by a phase inversion emulsification method) in the absence of a surfactant, the polymer itself has a functional group (especially an acidic group or a salt thereof), which causes an aqueous medium. It means water-insoluble polymer particles which can be dispersed in the water-insoluble polymer and do not contain a free emulsifier.
The self-dispersing polymer particles are preferable from the viewpoint of ejection stability and liquid stability (particularly dispersion stability) of the system containing the pigment, and among them, self-dispersing polymer particles having a carboxyl group are more preferable.

Here, the dispersed state refers to an emulsified state (emulsion) in which a water-insoluble polymer is dispersed in an aqueous medium and a dispersed state (suspension) in which a water-insoluble polymer is dispersed in a solid state in an aqueous medium. It includes both states.
The water-insoluble polymer in the present invention is preferably a water-insoluble polymer that can be in a dispersed state in which the water-insoluble polymer is dispersed in a solid state from the viewpoint of fixability when a liquid composition is used.

  Examples of a method for preparing an emulsified or dispersed state of the self-dispersing polymer, that is, an aqueous dispersion of the self-dispersing polymer include a phase inversion emulsification method. As the phase inversion emulsification method, for example, a self-dispersing polymer is dissolved or dispersed in a solvent (for example, a hydrophilic organic solvent) and then poured into water as it is without adding a surfactant. Examples include a method of obtaining an aqueous dispersion in an emulsified or dispersed state after stirring and mixing in a state in which a salt-forming group (for example, an acidic group) of the polymer is neutralized and removing the solvent.

  The dispersion state of the self-dispersing polymer particles refers to a solution in which 30 g of a water-insoluble polymer is dissolved in 70 g of an organic solvent (for example, methyl ethyl ketone), a neutralizing agent that can neutralize 100% of the salt-forming groups of the water-insoluble polymer (salt After mixing and stirring (equipment: stirring device with stirring blade, rotation speed 200 rpm, 30 minutes, 25 ° C.), sodium hydroxide if the generating group is anionic, acetic acid if cationic, and 200 g of water are mixed, It means a state in which even after removing the organic solvent from the mixed solution, it can be visually confirmed that the dispersion state exists stably at 25 ° C. for at least one week.

  The water-insoluble polymer means a polymer having a dissolution amount of 10 g or less when the polymer is dried at 105 ° C. for 2 hours and then dissolved in 100 g of water at 25 ° C., and the dissolution amount is preferable. Is 5 g or less, more preferably 1 g or less. The dissolution amount is the dissolution amount when neutralized with sodium hydroxide or acetic acid according to the kind of the salt-forming group of the water-insoluble polymer.

  The aqueous medium is configured to contain water, and may contain a hydrophilic organic solvent as necessary. In the present invention, it is preferably composed of water and 0.2% by mass or less of a hydrophilic organic solvent with respect to water, and more preferably composed of water.

  The main chain skeleton of the water-insoluble polymer is not particularly limited. For example, a vinyl polymer or a condensation polymer (epoxy resin, polyester, polyurethane, polyamide, cellulose, polyether, polyurea, polyimide, polycarbonate, etc.) is used. it can. Of these, vinyl polymers and polyurethanes are particularly preferred.

Suitable examples of monomers constituting the condensation polymer are described in JP-A No. 2001-247787. The polyurethane is synthesized by a polyaddition reaction using a diol compound and a diisocyanate compound as raw materials. For details of the diol compound and the diisocyanate compound, reference can be made to the descriptions in paragraph numbers [0031] to [0036] of JP-A No. 2001-247787.
Moreover, as a suitable example of the monomer which comprises a vinyl polymer and a vinyl polymer, what is described in Unexamined-Japanese-Patent No. 2001-181549 and Unexamined-Japanese-Patent No. 2002-88294 is mentioned. In addition, a radical transfer of a vinyl monomer using a chain transfer agent, a polymerization initiator, or an iniferter having a dissociable group (or a substituent that can be derived into a dissociable group), or a dissociable group in either an initiator or a terminator. A vinyl polymer in which a dissociable group is introduced at the end of a polymer chain by ionic polymerization using a compound having (or a substituent that can be derived from a dissociable group) can also be used.

  From the viewpoint of self-dispersibility, the polymer particle B preferably includes a water-insoluble polymer including a hydrophilic structural unit and a structural unit derived from an aromatic group-containing monomer.

The hydrophilic structural unit is not particularly limited as long as it is derived from a hydrophilic group-containing monomer, and even if it is derived from one kind of hydrophilic group-containing monomer, two or more hydrophilic groups are included. It may be derived from the contained monomer. The hydrophilic group is not particularly limited, and may be a dissociable group or a nonionic hydrophilic group.
The hydrophilic group is preferably a dissociable group and more preferably an anionic dissociative group from the viewpoint of promoting self-dispersion and the stability of the formed emulsified or dispersed state. Examples of the dissociable group include a carboxyl group, a phosphoric acid group, and a sulfonic acid group, and among them, a carboxyl group is preferable from the viewpoint of fixability when an aqueous ink is configured.

  From the viewpoint of self-dispersibility, the hydrophilic group-containing monomer is preferably a dissociable group-containing monomer, and is preferably a dissociable group-containing monomer having a dissociable group and an ethylenically unsaturated bond. Examples of the dissociable group-containing monomer include an unsaturated carboxylic acid monomer, an unsaturated sulfonic acid monomer, and an unsaturated phosphoric acid monomer.

Specific examples of the unsaturated carboxylic acid monomer include acrylic acid, methacrylic acid, crotonic acid, itaconic acid, maleic acid, fumaric acid, citraconic acid, and 2-methacryloyloxymethyl succinic acid.
Specific examples of the unsaturated sulfonic acid monomer include styrene sulfonic acid, 2-acrylamido-2-methylpropane sulfonic acid, 3-sulfopropyl (meth) acrylate, and bis- (3-sulfopropyl) -itaconate. Can be mentioned.
Specific examples of the unsaturated phosphoric acid monomer include vinylphosphonic acid, vinyl phosphate, bis (methacryloxyethyl) phosphate, diphenyl-2-acryloyloxyethyl phosphate, diphenyl-2-methacryloyloxyethyl phosphate, dibutyl-2 -Acryloyloxyethyl phosphate and the like.
Among the dissociable group-containing monomers, from the viewpoint of dispersion stability and ejection stability, unsaturated carboxylic acid monomers are preferable, acrylic monomers are more preferable, and acrylic acid and methacrylic acid are particularly preferable.

  From the viewpoint of self-dispersibility, the self-dispersing polymer particles preferably include a polymer having a carboxyl group and an acid value of 1 to 100 mgKOH / g. Furthermore, the acid value is more preferably 5 to 80 mgKOH / g, and further preferably 5 to 65 mgKOH / g, from the viewpoint of self-dispersibility. When the acid value is 1 mgKOH / g or more, self-dispersibility is stabilized, and when the acid value is 100 mgKOH / g or less, it is advantageous in terms of water resistance.

The aromatic group-containing monomer is not particularly limited as long as it is a compound containing an aromatic group and a polymerizable group. The aromatic group may be a group derived from an aromatic hydrocarbon or a group derived from an aromatic heterocycle. In the present invention, an aromatic group derived from an aromatic hydrocarbon is preferable from the viewpoint of particle shape stability in an aqueous medium.
Further, the polymerizable group may be a condensation polymerizable polymerizable group or an addition polymerizable polymerizable group. From the viewpoint of particle shape stability in an aqueous medium, the polymerizable group is preferably an addition polymerizable polymerizable group, and more preferably a group containing an ethylenically unsaturated bond.

The aromatic group-containing monomer is preferably a monomer having an aromatic group derived from an aromatic hydrocarbon and an ethylenically unsaturated bond. The aromatic group-containing monomer may be used alone or in combination of two or more.
Examples of the aromatic group-containing monomer include phenoxyethyl (meth) acrylate, benzyl (meth) acrylate, phenyl (meth) acrylate, and a styrene monomer. Of these, aromatic group-containing (meth) acrylate monomers are preferred from the viewpoint of the balance between the hydrophilicity and hydrophobicity of the polymer chain and the ink fixability, and include phenoxyethyl (meth) acrylate, benzyl (meth) acrylate, and phenyl (meth). At least one selected from acrylates is more preferable, and phenoxyethyl (meth) acrylate and benzyl (meth) acrylate are more preferable.
“(Meth) acrylate” means acrylate or methacrylate.

  The self-dispersing polymer is preferably an acrylic resin containing a structural unit derived from a (meth) acrylate monomer, preferably an acrylic resin containing a structural unit derived from an aromatic group-containing (meth) acrylate monomer. It is preferable that the structural unit derived from a group-containing (meth) acrylate monomer is 10 to 95% by mass. When the content of the aromatic group-containing (meth) acrylate monomer is 10 to 95% by mass, the stability of the self-emulsification or dispersion state is improved, and further the increase in ink viscosity can be suppressed. The content of the aromatic group-containing (meth) acrylate monomer is: self-dispersed state stability, particle shape stabilization in aqueous media due to hydrophobic interaction between aromatic rings, and water solubility due to moderate hydrophobicity of particles. From the viewpoint of lowering the component amount, it is more preferably 15 to 90% by mass, further preferably 15 to 80% by mass, and particularly preferably 25 to 70% by mass.

  The self-dispersing polymer can be constituted using, for example, a structural unit derived from an aromatic group-containing monomer and a structural unit derived from a dissociable group-containing monomer. Furthermore, other structural units may be further included as necessary.

The monomer that forms the other structural unit is not particularly limited as long as it is a monomer copolymerizable with the aromatic group-containing monomer and the dissociable group-containing monomer. Among these, an alkyl group-containing monomer is preferable from the viewpoint of flexibility of the polymer skeleton and ease of control of the glass transition temperature (Tg).
Examples of the alkyl group-containing monomer include methyl (meth) acrylate, ethyl (meth) acrylate, isopropyl (meth) acrylate, n-propyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, Alkyl (meth) acrylates such as t-butyl (meth) acrylate, hexyl (meth) acrylate, ethylhexyl (meth) acrylate, and hydroxymethyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, 2-hydroxypropyl (meth) ) Ethylenically unsaturated monomers having hydroxyl groups such as acrylate, 4-hydroxybutyl (meth) acrylate, hydroxypentyl (meth) acrylate, hydroxyhexyl (meth) acrylate, and dimethyl Ruaminoechiru (meth) dialkylaminoalkyl (meth) acrylates such as acrylates, alkyl esters of (meth) acrylic acid etc. (preferably, (meth) alkyl ester having 1 to 4 carbon atoms of acrylic acid);
N-hydroxymethyl (meth) acrylamide, N-hydroxyethyl (meth) acrylamide, N-hydroxyalkyl (meth) acrylamide such as N-hydroxybutyl (meth) acrylamide, N-methoxymethyl (meth) acrylamide, N-ethoxy Methyl (meth) acrylamide, N- (n-, iso) butoxymethyl (meth) acrylamide, N-methoxyethyl (meth) acrylamide, N-ethoxyethyl (meth) acrylamide, N- (n-, iso) butoxyethyl ( And (meth) acrylamide monomers such as (meth) acrylamides such as N-alkoxyalkyl (meth) acrylamides such as (meth) acrylamide.

The molecular weight of the polymer b constituting the polymer particle B (including the self-dispersing polymer particle) is preferably 3000 to 200,000, more preferably 5000 to 150,000 in terms of weight average molecular weight. More preferably, it is 100,000. By setting the weight average molecular weight to 3000 or more, the amount of water-soluble components can be effectively suppressed. Moreover, self-dispersion stability can be improved by making a weight average molecular weight into 200,000 or less.
The weight average molecular weight is a value measured by gel permeation chromatography (GPC), and the measuring method is as described in the section of polymer A.

Among these, the water-insoluble polymer constituting the polymer particle B (including self-dispersing polymer particles) is a structural unit derived from an aromatic group-containing (meth) acrylate monomer (preferably from the viewpoint of controlling hydrophilicity / hydrophobicity of the polymer). Includes 15 to 80% by mass of the total mass of the self-dispersing polymer particles with a copolymerization ratio of a structural unit derived from phenoxyethyl (meth) acrylate and / or a structural unit derived from benzyl (meth) acrylate). preferable.
In addition, the water-insoluble polymer has a constitution derived from a carboxyl group-containing monomer having a copolymerization ratio of 15 to 80% by mass of a constitutional unit derived from an aromatic group-containing (meth) acrylate monomer from the viewpoint of controlling the hydrophilicity / hydrophobicity of the polymer. And a structural unit derived from an alkyl group-containing monomer (preferably a structural unit derived from an alkyl ester of (meth) acrylic acid), and a structural unit derived from phenoxyethyl (meth) acrylate and / or Alternatively, a structural unit derived from benzyl (meth) acrylate as a copolymerization ratio of 15 to 80% by mass, a structural unit derived from a carboxyl group-containing monomer, and a structural unit derived from an alkyl group-containing monomer (preferably (meth) Structural unit derived from an alkyl ester having 1 to 4 carbon atoms of acrylic acid) More preferably, the acid value is 25 to 100 and the weight average molecular weight is preferably 3000 to 200,000, the acid value is 25 to 95, and the weight average molecular weight is 5000 to 150,000. It is more preferable that

  Specific examples of the water-insoluble polymer constituting the polymer particle B include phenoxyethyl acrylate / methyl methacrylate / acrylic acid copolymer (50/45/5), phenoxyethyl acrylate / benzyl methacrylate / isobutyl methacrylate / methacrylic acid copolymer. Copolymer (30/35/29/6), phenoxyethyl methacrylate / isobutyl methacrylate / methacrylic acid copolymer (50/44/6), phenoxyethyl acrylate / methyl methacrylate / ethyl acrylate / acrylic acid copolymer (30/55 / 10/5), benzyl methacrylate / isobutyl methacrylate / methacrylic acid copolymer (35/59/6), styrene / phenoxyethyl acrylate / methyl methacrylate / acrylic acid copolymer (10/50/35/5), benzyl Acrylate / Methyl methacrylate / Crylic acid copolymer (55/40/5), phenoxyethyl methacrylate / benzyl acrylate / methacrylic acid copolymer (45/47/8), styrene / phenoxyethyl acrylate / butyl methacrylate / acrylic acid copolymer (5 / 48/40/7), benzyl methacrylate / isobutyl methacrylate / cyclohexyl methacrylate / methacrylic acid copolymer (35/30/30/5), phenoxyethyl acrylate / methyl methacrylate / butyl acrylate / methacrylic acid copolymer (12/50 / 30/8), benzyl acrylate / isobutyl methacrylate / acrylic acid copolymer (93/2/5), styrene / phenoxyethyl methacrylate / butyl acrylate / acrylic acid copolymer (50/5/20/25), styrene / Butyl acrylate / acrylic acid copolymer (62/35/3), methyl methacrylate Acrylate / phenoxyethyl acrylate / acrylic acid copolymer (45/51/4), methyl methacrylate / phenoxyethyl acrylate / acrylic acid copolymer (45/49/6), methyl methacrylate / phenoxyethyl acrylate / acrylic acid copolymer Polymer (45/48/7), methyl methacrylate / phenoxyethyl acrylate / acrylic acid copolymer (45/47/8), methyl methacrylate / phenoxyethyl acrylate / acrylic acid copolymer (45/45/10), etc. Is mentioned. However, the present invention is not limited to these. In addition, the numerical value in the said parenthesis represents the mass ratio of a copolymerization component.

  As the polymer particles B, urethane resin particles are preferable from the viewpoint of further improving the continuous discharge property and discharge stability of the water-based ink. The urethane resin is less susceptible to degradation due to photolysis than the acrylic polymer, so that an image using the ink containing the urethane resin is excellent in light resistance. As the urethane resin particles, particles containing at least one of the resins represented by UP-1 to UP-4 below are suitable.

In UP-1 to UP-4, R represents an aliphatic group or an aromatic group. R ¹ is — (CH ₂ ) _m —COOH or — (CH ₂ CH ₂ O) _p —CH ₃ , m is an integer of 1 to 10, and p is an integer of 1 to 100. X is NH or O. n is an arbitrary integer.

  The urethane resin represented by UP-1 to UP-4 preferably has an aspect in which a crosslink is present in the resin. This improves the shear stability of the urethane resin particles. In addition, the urethane resin represented by UP-1 to UP-4 preferably includes an acidic group from the viewpoint of improving the stability of the polyurethane particles.

  A method for producing the urethane-based resins represented by UP-1 to UP-4 and preferred embodiments thereof is not particularly limited, but for example, a production method described in JP-A-2006-241457 is suitable. That is, it is a production method in which an emulsion containing an isocyanate compound and an anionic surfactant is prepared, and a bifunctional, trifunctional or polyfunctional reactant is added thereto and stirred to produce a urethane resin.

Commercially available products may be used as the urethane resin particles. As an example of a commercial product, Acrit WBR-016U (Tg: 20 ° C), WEM-321U (Tg: 20 ° C), WBR-2018 (Tg: 20 ° C), WBR-2000U (Tg) manufactured by Taisei Fine Chemical Co., Ltd. : 45 ° C), WBR-601U (Tg: -30 ° C), PUE-1000, PUE-1020A, PUE-1370, PUE-1370, PUE-800, manufactured by Murayama Chemical Laboratory, Daiichi Kogyo Seiyaku Co., Ltd. Superflex 650, 860, 210, Neotan UE-1100, manufactured by Toagosei Co., Ltd., Ucourt UX-150, Sanyo Chemical Industries, UWS-145, Barmarin UA-150, UA-368, Iupylene UXA-307 And so on.
In the present invention, resins having a composition other than the urethane-based resin can be preferably used. For example, John Crill 741 (Tg: 15 ° C., styrene / acrylic) manufactured by Johnson Polymer Co., Ltd., 775 (Tg: 37 ° C., styrene / acrylic), 537 (Tg: 49 ° C., styrene / acrylic), 538 (Tg: 66 ° C., styrene / acrylic), Aron HD-5 manufactured by Toagosei Co., Ltd. (Tg: 45) (C, acrylic), Nichigo's Movinyl 742N (Tg: 37 ° C., acrylic), and the like.

  There is no restriction | limiting in particular as a manufacturing method of the water-insoluble polymer which comprises a polymer particle. For example, a method in which emulsion polymerization is performed in the presence of a polymerizable surfactant and a surfactant and a water-insoluble polymer are covalently bonded, and a monomer mixture containing a hydrophilic group-containing monomer and an aromatic group-containing monomer is solution-polymerized. And a method of copolymerization by a known polymerization method such as a bulk polymerization method. Among the polymerization methods, a solution polymerization method is preferable from the viewpoint of droplet ejection stability when an ink is used, and a solution polymerization method using an organic solvent is more preferable.

The polymer particles include a polymer synthesized in an organic solvent, and the polymer has a carboxyl group (preferably having an acid value of 5 to 65 mgKOH / g), and part or all of the carboxyl groups of the polymer are It is preferably prepared as a polymer dispersion that is neutralized and has water as a continuous phase. That is, the production of polymer particles in the present invention can be performed by providing a step of synthesizing a polymer in an organic solvent and a dispersion step of preparing an aqueous dispersion in which at least a part of the carboxyl groups of the polymer is neutralized. preferable.
The dispersion step preferably includes the following step (1) and step (2).
-Step (1): Step of stirring a mixture containing a polymer (water-insoluble polymer), an organic solvent, a neutralizing agent, and an aqueous medium-Step (2): Step of removing the organic solvent from the mixture

  The step (1) is preferably a treatment in which a polymer (water-insoluble polymer) is first dissolved in an organic solvent, then a neutralizing agent and an aqueous medium are gradually added, mixed and stirred to obtain a dispersion. In this way, by adding a neutralizing agent and an aqueous medium to a water-insoluble polymer solution dissolved in an organic solvent, a self-dispersing polymer having a particle size with higher storage stability without requiring strong shearing force. Particles can be obtained. There is no restriction | limiting in particular in the stirring method of a mixture, Dispersing machines, such as a generally used mixing stirring apparatus and an ultrasonic disperser, a high-pressure homogenizer, can be used as needed.

  Preferred examples of the organic solvent include alcohol solvents, ketone solvents, and ether solvents. Regarding the details of these organic solvents, the description in paragraph [0109] of JP2011-42150A can be applied. Among these, a ketone solvent such as methyl ethyl ketone and an alcohol solvent such as isopropyl alcohol are preferable, and isopropyl alcohol and methyl ethyl ketone are preferably used from the viewpoint of mildly changing the polarity at the phase inversion from oil to water. By using the solvent in combination, it is possible to obtain self-dispersing polymer particles having a fine particle size with high dispersion stability without aggregation and sedimentation and fusion between particles.

The neutralizing agent is used so that a part or all of the dissociable group is neutralized and the self-dispersing polymer forms a stable emulsified or dispersed state in water. When the self-dispersing polymer has an anionic dissociative group (for example, carboxyl group) as a dissociable group, examples of the neutralizing agent used include basic compounds such as organic amine compounds, ammonia, and alkali metal hydroxides. It is done. Regarding the details of these neutralizing agents, the description in paragraph number [0110] of JP-A-2011-42150 can be applied. Among these, sodium hydroxide, potassium hydroxide, triethylamine, and triethanolamine are preferable from the viewpoint of stabilizing the dispersion of the self-dispersing polymer particles in water.
These basic compounds are preferably used in an amount of 5 to 120 mol% with respect to 100 mol% of the dissociable group. Details of the ratio here are described in paragraph number [0111] of Japanese Patent Application Laid-Open No. 2011-42150.

  In the step (2), an aqueous dispersion of polymer particles is obtained by distilling off the organic solvent from the dispersion obtained in the step (1) by a conventional method such as distillation under reduced pressure and phase-inversion into an aqueous system. Can be obtained. The organic solvent in the obtained aqueous dispersion has been substantially removed, and the amount of the organic solvent is preferably 0.2% by mass or less, more preferably 0.1% by mass or less.

The average particle size of the polymer particles B (particularly self-dispersing polymer particles) is preferably in the range of 10 to 400 nm, more preferably in the range of 10 to 200 nm, still more preferably in the range of 10 to 100 nm, particularly preferably in terms of volume average particle size. Is in the range of 10-50 nm. Manufacturability is improved when the average particle size is 10 nm or more. Moreover, storage stability improves because an average particle diameter is 400 nm or less. Moreover, there is no restriction | limiting in particular regarding the particle size distribution of a polymer particle, Any of what has a wide particle size distribution or a monodispersed particle size distribution may be sufficient. Two or more water-insoluble particles may be mixed.
The average particle size and particle size distribution of the polymer particles are determined by measuring the volume average particle size by a dynamic light scattering method using a nanotrack particle size distribution measuring device UPA-EX150 (manufactured by Nikkiso Co., Ltd.). It is

  The glass transition temperature (Tg) of the polymer particles B is preferably 5 ° C. or more and 60 ° C. or less, more preferably 10 ° C. or more and 60 ° C. or less, and more preferably 15 ° C. or more and 50 ° C. or less from the viewpoint of storage stability of the ink composition. preferable. When the Tg is within the above range, the image is hard to be hardened or sticky, the texture such as a touch feeling (for example, the image is not hard or sticky) is improved, and the scratch resistance of the image is improved. It can be improved further.

  The content of the polymer particles B in the ink composition is preferably 1% by mass or more and 30% by mass or less, and preferably 5% by mass or more and 15% by mass or less with respect to the total amount of the ink composition from the viewpoint of image scratch resistance. Is more preferable. The polymer particles B (particularly self-dispersing polymer particles) can be used alone or in combination of two or more.

  In the ink composition of the present invention, the content ratio (A: B) of the polymer particles A and the polymer particles B is preferably in the range of 0.1: 9.9 to 3: 7 by mass ratio. The range of 5: 9.5 to 2: 8 is more preferable. When the content ratio A: B is equal to or more than the lower limit value, the adhesion of the image is improved, and the scratch resistance is further improved. Further, when the content ratio A: B is equal to or less than the upper limit value, it is possible to maintain good image scratch resistance.

  The total amount of the polymer particles A and the polymer particles B is preferably 0.1% by mass or more and 20% by mass or less in terms of solid content with respect to the total amount of the ink composition. Especially, it is more preferable that the total amount is not less than 0.5% by mass and not more than 10% by mass. When the total amount is 0.1% by mass or more, the adhesion of the image can be improved and the scratch resistance can be further improved. Further, when the total amount is 20% by mass or less, the viscosity can be maintained in a range suitable for discharge, and discharge stability and maintainability can be favorably maintained.

(Coloring agent)
The water-based ink in the present invention contains at least one colorant. As the colorant, pigments, dyes and the like are suitable, and among these, pigments are preferred from the viewpoint of light resistance of images. There is no restriction | limiting in particular as a pigment, According to the objective, it can select suitably, For example, any of an organic pigment and an inorganic pigment may be sufficient. The pigment is preferably a pigment that is almost insoluble or hardly soluble in water from the viewpoint of ink colorability.

Examples of organic pigments include polycyclic cyclic compounds such as azo lakes, azo pigments, phthalocyanine pigments, perylene and perinone pigments, anthraquinone pigments, quinacridone pigments, dioxazine pigments, diketopyrrolopyrrole pigments, thioindigo pigments, isoindolinone pigments, and quinophthalone pigments. Pigments: Dye lakes such as basic dye type lakes and acid dye type lakes; nitro pigments, nitroso pigments, aniline black, daylight fluorescent pigments and the like. Examples of the inorganic pigment include titanium oxide, iron oxide, and carbon black. Any pigment that is not described in the color index can be used as long as it is dispersible in the aqueous phase.
Further, pigments obtained by surface treatment with a surfactant, a polymer dispersing agent or the like, or graft carbon can also be used.

~ Dispersant ~
The water-based ink in the present invention can contain at least one dispersant. The pigment dispersant may be either a polymer dispersant or a low molecular surfactant type dispersant. The polymer dispersant may be either a water-soluble dispersant or a water-insoluble dispersant. “Water-insoluble” means that the amount of dissolution is 10 g or less when the dispersant is dried at 105 ° C. for 2 hours and then dissolved in 100 g of water at 25 ° C.

  The low molecular surfactant type dispersant can stably disperse the pigment in the aqueous solvent while keeping the ink at a low viscosity. The low molecular surfactant type dispersant is a low molecular dispersant having a molecular weight of 2,000 or less. The molecular weight of the low molecular surfactant type dispersant is preferably 100 to 2,000, and more preferably 200 to 2,000.

  The low molecular surfactant type dispersant has a structure including a hydrophilic group and a hydrophobic group. Moreover, the hydrophilic group and the hydrophobic group should just be independently contained 1 or more in 1 molecule, respectively, and may have multiple types of hydrophilic group and hydrophobic group. In addition, a linking group for linking a hydrophilic group and a hydrophobic group can be appropriately included.

  The hydrophilic group is anionic, cationic, nonionic, or a betaine type that combines these. The anionic group may be any one as long as it has a negative charge, and may be a phosphoric acid group, a phosphonic acid group, a phosphinic acid group, a sulfuric acid group, a sulfonic acid group, a sulfinic acid group, or a carboxylic acid group. Preferably, it is a phosphoric acid group or a carboxylic acid group, and more preferably a carboxylic acid group. The cationic group may be any one having a positive charge, but is preferably an organic cationic substituent, and more preferably a nitrogen or phosphorus cationic group. Further, it is more preferably a pyridinium cation or an ammonium cation. Examples of the nonionic group include polyethylene oxide, polyglycerin, and a part of a sugar unit.

  The hydrophilic group is preferably an anionic group. The anionic group is preferably a phosphoric acid group, a phosphonic acid group, a phosphinic acid group, a sulfuric acid group, a sulfonic acid group, a sulfinic acid group, or a carboxylic acid group, and more preferably a phosphoric acid group or a carboxylic acid group. Preferably, it is a carboxylic acid group.

The hydrophobic group has a hydrocarbon-based, fluorocarbon-based, silicone-based or the like structure, and is particularly preferably a hydrocarbon-based group. Further, the hydrophobic group may have a linear structure or a branched structure. Further, the hydrophobic group may have a single chain structure or a chain structure of more than this, and in the case of a structure of two or more chains, it may have a plurality of types of hydrophobic groups.
The hydrophobic group is preferably a hydrocarbon group having 2 to 24 carbon atoms, more preferably a hydrocarbon group having 4 to 24 carbon atoms, and further preferably a hydrocarbon group having 6 to 20 carbon atoms.

  Among the polymer dispersants, examples of the water-soluble dispersant include hydrophilic polymer compounds. For example, natural hydrophilic polymer compounds include plant polymers such as gum arabic, tragan gum, guar gum, karaya gum, locust bean gum, arabinogalactone, pectin, quince seed starch, seaweeds such as alginic acid, carrageenan and agar. Examples include molecules, animal polymers such as gelatin, casein, albumin and collagen, and microorganism polymers such as xanthene gum and dextran.

In addition, in hydrophilic polymer compounds modified from natural products, fiber polymers such as methylcellulose, ethylcellulose, hydroxyethylcellulose, hydroxypropylcellulose, carboxymethylcellulose, starch such as sodium starch glycolate and sodium starch phosphate And seaweed polymers such as sodium alginate, propylene glycol alginate, and the like.
Further, synthetic hydrophilic polymer compounds include vinyl polymers such as polyvinyl alcohol, polyvinyl pyrrolidone, and polyvinyl methyl ether, non-crosslinked polyacrylamide, polyacrylic acid or alkali metal salts thereof, water-soluble styrene acrylic resins, and the like. Acrylic resin, water-soluble styrene maleic acid resin, water-soluble vinyl naphthalene acrylic resin, water-soluble vinyl naphthalene maleic resin, polyvinyl pyrrolidone, polyvinyl alcohol, alkali metal salts of β-naphthalene sulfonic acid formalin condensate, quaternary ammonium and amino And a polymer compound having a salt of a cationic functional group such as a group in the side chain, a natural polymer compound such as shellac, and the like.

  Among these, from the viewpoint of dispersion stability of the pigment, a polymer compound containing a carboxyl group is preferable. For example, an acrylic resin such as a water-soluble styrene acrylic resin, a water-soluble styrene maleic acid resin, a water-soluble vinyl naphthalene acrylic resin, A polymer compound containing a carboxyl group such as a water-soluble vinyl naphthalene maleic resin is particularly preferable.

  Among the polymer dispersants, as the water-insoluble dispersant, a polymer having both a hydrophobic portion and a hydrophilic portion can be used. For example, styrene- (meth) acrylic acid copolymer, styrene- (meth) acrylic acid- (meth) acrylic acid ester copolymer, (meth) acrylic acid ester- (meth) acrylic acid copolymer, polyethylene glycol ( Examples thereof include (meth) acrylate- (meth) acrylic acid copolymers, vinyl acetate-maleic acid copolymers, and styrene-maleic acid copolymers.

  The weight average molecular weight of the polymer dispersant is preferably 3,000 to 200,000, more preferably 5,000 to 100,000, still more preferably 5,000 to 80,000, and particularly preferably 10,000 to 60. , 000.

  From the viewpoint of self-dispersibility, the polymer dispersant preferably contains a polymer having a carboxyl group, preferably a polymer having a carboxyl group and an acid value of 100 mgKOH / g or less, and an acid value of 25 to 100 mgKOH. / G polymer is more preferred.

  Further, the mixing mass ratio of the pigment and the dispersant (pigment: dispersant) is preferably in the range of 1: 0.06 to 1: 3, more preferably in the range of 1: 0.125 to 1: 2. Preferably it is 1: 0.125 to 1: 1.5.

A dye may be used in place of the pigment. In the case of using a dye, a dye held on a water-insoluble carrier can be used. As the dye, known dyes can be used without limitation. For example, the dyes described in JP-A No. 2001-115066, JP-A No. 2001-335714, JP-A No. 2002-249677 and the like are preferably used. . The carrier is not particularly limited as long as it is insoluble or hardly soluble in water, and can be selected from inorganic materials, organic materials, and composite materials thereof. Specifically, the carriers described in JP-A Nos. 2001-181549 and 2007-169418 are preferably used.
The carrier holding the dye (water-insoluble colored particles) can be used as an aqueous dispersion using a dispersant. As the dispersant, the above-described dispersants can be suitably used.

  In the present invention, it is preferable to contain a pigment and a dispersant from the viewpoint of scratch resistance and quality of an image, and an organic pigment and a polymer dispersant are included, and at least a part of the pigment surface is coated with the polymer dispersant. More preferably, it is contained as a water-dispersible pigment. Furthermore, it is particularly preferable that the water-based ink contains a water-dispersible pigment containing an organic pigment and a polymer dispersant containing a carboxyl group, and at least a part of the pigment surface being coated with a polymer dispersant having a carboxyl group.

The average particle size of the pigment in the dispersed state is preferably 10 to 200 nm, more preferably 10 to 150 nm, and still more preferably 10 to 100 nm. When the average particle size is 200 nm or less, the color reproducibility is good, and the droplet ejection characteristics when droplets are ejected by the ink jet method are good. When the average particle size is 10 nm or more, light resistance is improved. Further, the particle size distribution of the color material is not particularly limited, and may be either a wide particle size distribution or a monodisperse particle size distribution. Two or more color materials having a monodisperse particle size distribution may be mixed and used.
Here, the average particle diameter of the pigment in the dispersed state indicates the average particle diameter in the ink state, but the same applies to the so-called concentrated ink dispersion in the previous stage before the ink is formed.

  The average particle diameter of the pigment in the dispersed state, and the average particle diameter and particle size distribution of the polymer particles described later are measured using dynamic light using a nanotrack particle size distribution measuring device UPA-EX150 (manufactured by Nikkiso Co., Ltd.). It is obtained by measuring the volume average particle diameter by a scattering method.

You may use a pigment individually by 1 type or in combination of 2 or more types.
The content of the pigment in the water-based ink is preferably 1 to 25% by mass and more preferably 2 to 15% by mass with respect to the total amount of the ink from the viewpoint of image density.

(Wax particles)
The water-based ink in the present invention preferably contains wax particles together with the polymer resin. By containing the wax particles, the coefficient of friction on the image surface is lowered, and the scratch resistance can be further improved. Also, the wax particles can enhance the texture such as touch feeling (for example, there is no hardness or stickiness of the image).

  The content of the wax particles in the water-based ink is preferably 0.5% by mass or more and less than 8% by mass with respect to the total amount of the ink in terms of the wax solid content concentration. When the content of the wax particles in the water-based ink is less than 8% by mass, the dischargeability is good, the hardness or stickiness of the image can be suppressed to maintain the texture, and the scratch resistance is excellent. The content of 0.5% by mass or more indicates that the wax particles are positively contained. The content of the wax particles in the water-based ink is preferably 1% by mass or more and less than 8% by mass, and more preferably 1% by mass or more and 6% by mass or less.

Examples of the wax particles include natural wax and synthetic wax particles.
Examples of natural waxes include petroleum waxes, plant waxes, and animal and plant waxes. Among these, examples of petroleum waxes include paraffin wax, microcrystalline wax, petrolatum, etc., examples of plant waxes, carnauba wax, candelilla wax, rice wax, wood wax, etc. as examples of animal plant waxes. Lanolin, beeswax and the like.
Synthetic waxes include synthetic hydrocarbon waxes and modified waxes. Among these, examples of synthetic hydrocarbon waxes include polyethylene wax, Fischer-Tropsch wax, and examples of modified wax waxes include paraffin wax derivatives, montan wax derivatives, microcrystalline wax derivatives, and the like.

Among the waxes, carnauba wax is preferable from the viewpoint of improving the scratch resistance of the image, and is preferable from the viewpoint of improving the image strength in post-processing of the image sample (processing into a booklet or the like). In addition, paraffin wax mainly composed of hydrocarbons having 20 to 40 carbon atoms is preferable from the viewpoints of glossiness of images, prevention of water evaporation from the nozzle tip, and excellent water retention effect. In addition, polyethylene wax is preferred from the viewpoint of excellent compatibility with the resin and easy to obtain a homogeneous and good image. From the viewpoint of imparting wettability, polyethylene wax is preferred. Polyethylene wax is easily modified. For example, glycol-modified glycol-modified polyethylene wax has a wetting effect due to glycol, and is effective in maintaining the wettability of water-based ink at the nozzle tip. By containing polyethylene wax, it is preferable in that the discharge stability can be maintained even higher.
Among these, linear higher fatty acid ester wax particles and hydrocarbon wax particles are preferable from the viewpoint of improving the scratch resistance.

  The melting point (Tm) of the wax particles is preferably 50 ° C. or higher and 150 ° C. or lower, and more preferably 50 ° C. or higher and 140 ° C. or lower. When the melting point is 50 ° C. or higher, the slipperiness of the image is improved and the scratch resistance can be further improved. Further, even when the melting point is 150 ° C. or lower, the slipperiness of the image is improved, and the scratch resistance can be further improved.

  The wax particles preferably have a weight average molecular weight or a molecular weight of less than 3000. When the weight average molecular weight or the molecular weight is less than 3000, it is advantageous in terms of friction resistance of the formed image. As a weight average molecular weight or molecular weight, More preferably, it is 2000 or less, More preferably, it is 1000 or less. The lower limit of the weight average molecular weight or molecular weight is preferably 500 from the viewpoint of the friction resistance of the formed image.

  The wax may be contained in the ink in any form such as a solution form dissolved in a suitable solvent, an emulsified dispersion, or a solid particle dispersion. The wax is preferably added in the form of a dispersion in which particles are dispersed. For example, an aqueous dispersion (specifically, emulsion (emulsion dispersion) or suspension) in which the particle wax is dispersed in water. Any of (solid particle dispersion) may be used.

  For emulsification and dispersion, use an oil such as dibutyl phthalate, tricresyl phosphate, dioctyl sebacate, or tri (2-ethylhexyl) phosphate, or an auxiliary solvent such as ethyl acetate or cyclohexanone, and add an emulsifying dispersant. And a method of mechanically preparing an emulsified dispersion. At this time, it is also preferable to add a polymer such as α-methylstyrene oligomer or poly (t-butylacrylamide) for the purpose of adjusting the viscosity and refractive index of the oil droplets.

  As a method for dispersing solid particles, a lubricant powder is dispersed in a suitable solvent such as water by a ball mill, a colloid mill, a vibrating ball mill, a sand mill, a jet mill, a roller mill, or an ultrasonic wave to form a solid dispersion. Is mentioned. In this case, a protective colloid (for example, polyvinyl alcohol) or a surfactant (for example, an anionic surfactant such as sodium triisopropylnaphthalenesulfonate (a mixture of three isopropyl groups having different substitution positions)) may be used. . In the mill, beads such as zirconia are generally used as a dispersion medium. The aqueous dispersion may contain a preservative (for example, benzoisothiazolinone sodium salt).

  The wax is preferably used as an emulsified dispersion by an emulsifying dispersion method. At this time, the average particle size of the dispersed particles (wax particles) in the emulsified dispersion is preferably 0.01 μm to 10 μm, more preferably 0.05 μm to 5 μm, and still more preferably 0.1 μm to 2 μm. The emulsified dispersion and the dispersion thereof will be described later.

The wax is suitably used in the form of an emulsified dispersion using an emulsifying dispersant.
As an emulsifying dispersant, it can be appropriately selected from a number of conventionally known emulsifying dispersants. Among these, a preferable emulsifying dispersant is a dispersant represented by the following general formula (2).
(R ¹ ) _a -G- (D) _d: General formula (2)
In the general formula (2), R ¹ is an alkyl group containing a straight chain, branched or cyclic group having 10 to 60 carbon atoms, an alkenyl group containing a linear, branched or cyclic group having 10 to 60 carbon atoms, or 10 to 10 carbon atoms. It represents an aralkyl group containing 60 straight chain, branched or cyclic, or an aryl group having 10 to 60 carbon atoms, and these may have a substituent or may be unsubstituted.

Preferable examples of R ¹ include alkyl represented by C _g H _{2g + 1} (g represents an integer of 10 to 60), specifically, dodecyl, myristyl, cetyl, stearyl, stearyl, oleyl, eicosyl, Examples include docosanyl, triacontacyl, tetracontacil, heptacontacil, dinonylphenyl, didodecylphenyl, tetradecylphenyl, tripentylphenyl, dodecylnaphthyl and the like.

  G represents 2 to 7 valent, preferably 2 to 5 valent, more preferably 2 to 4 valent, and still more preferably a divalent or trivalent linking group or a single bond. G is preferably an alkylene group, an arylene group, or a composite group thereof. G may be a divalent substituted or unsubstituted linking group interrupted by a different atom, such as an oxygen atom, an ester group, sulfur, an amide group, a sulfonyl group, or sulfur. G is particularly preferably an oxygen atom, an ester group or an amide group.

D represents a polyoxyalkylene group represented by (B) _n -E. It is _{B, -CH 2 CH 2 O -} , - CH 2 CH 2 CH 2 O -, - CH (CH 3) CH 2 O-, or _{-CH 2 CH (OH) CH 2} O- and represent, preferably - CH ₂ CH ₂ is O-.
n represents an integer of 1 to 50, preferably an integer of 5 to 30.

E represents a hydrogen atom, an alkyl group having 1 to 8 carbon atoms, an aryl group, an alkylcarbonyl group having 2 to 8 carbon atoms, or an arylcarbonyl group, which may have a substituent or unsubstituted. It may be.
The alkyl group having 1 to 8 carbon atoms is preferably methyl, ethyl, propyl, butyl, hexyl or cyclohexyl, and particularly preferably methyl, ethyl or propyl.
The aryl group is preferably a phenyl group.
The alkylcarbonyl group having 2 to 8 carbon atoms is preferably acetyl, propionyl, butyroyl, pivaloyl or cyclohexanecarbonyl, particularly preferably acetyl.
The arylcarbonyl group is preferably a benzoyl group.
Of the E, a hydrogen atom, methyl, methyl, propyl, acetyl, propionyl, and benzoyl are particularly preferable.

a and d each independently represents an integer of 1 to 6;
When R ^{1, D,} and E is there are a plurality, the plurality of R ^1, D, and E may each be the same or different from each other.

  In addition, it is desirable that the dispersant represented by the general formula (2) has low solubility in an aqueous system. For example, a dispersant having a solubility in water of 0.5% by mass or less (25 ° C.) is preferable. Preferable is 0.1% by mass or less.

Specific examples of the dispersant represented by the general formula (2) are given below. However, it is not limited to these.

  As the solvent when the wax particles are added in the form of a dispersion, water is preferable. However, the solvent is not limited to water, and for example, a normal organic solvent may be appropriately selected and used at the time of dispersion. Regarding the organic solvent, reference can be made to the description of paragraph number [0027] of JP-A-2006-91780. By using an organic solvent, the stability of the lubricant dispersion is superior. The organic solvent may be used by mixing two or more kinds of the same or different kinds of solvents.

  The component ratio of the two components in the wax-dispersed particles using the wax and the dispersant of the general formula (2) is not particularly limited, and is 25 to 99% by mass of the lubricant and 1 to 75% by mass of the dispersant. The case is preferred. By setting the ratio of the wax within the above range, the properties of the wax-dispersed particles are more exhibited. Accordingly, it is preferable that the content ratio of the dispersant represented by the general formula (2) in the wax dispersed particles is small.

The wax-dispersed particles are preferably prepared by mixing at a higher temperature than that of the compound having a higher melting point before being dispersed, and so-called melt mixing. Similarly, the organic solvent serving as the dispersion medium is heated to a high temperature in the same manner, and the molten mixture is added thereto, and finely dispersed by various dispersion methods. It is also preferable to add a heated organic solvent to the molten mixture to disperse and form particles. Also, after dissolving these in a non-aqueous organic solvent that dissolves the wax or dispersant, finely disperse it in water using another water-soluble surfactant, and add it as dispersed wax particles. For example, as the non-aqueous organic solvent, ethyl acetate or the like is preferable.
When the organic solvent is removed after dispersion and used as a wax particle dispersion, it is dissolved and mixed in the organic solvent at a low temperature even when the melting point of the wax and the compound represented by the general formula (2) is 100 ° C. or higher. It is possible to prepare high-melting-point lubricant-dispersed particles in an aqueous system. Here, the melting point of the wax and the general formula (2) is not particularly limited, but the preferable melting point is 50 ° C. or more and 200 ° C. or less, more preferably 60 ° C. or more and 200 ° C. or less, and further preferably 80 ° C. It is 150 degreeC or more.
Among the above, water is most preferable in preparing a water-based ink in terms of low environmental load. When a lubricant having a melting point of 80 ° C. is used together with water, it is preferable to disperse the water at a temperature of 80 ° C. or higher.

(Water-soluble organic solvent)
The water-based ink in the present invention can contain water as a solvent and a water-soluble organic solvent. By containing the water-soluble organic solvent together with the polymer particles, the minimum film-forming temperature of the polymer particles can be kept low in the ink, and the discharge properties and the like can be kept good.
Here, water-soluble means to dissolve 1% by mass or more in 20 ° C. water.

  As the water-soluble organic solvent constituting the water-based ink, alkyleneoxy alcohol and alkyleneoxyalkyl ether are preferable. When these organic solvents are included, curling of recorded matter in a high humidity environment can be suppressed.

  The alkyleneoxy alcohol is preferably propyleneoxy alcohol. Examples of propyleneoxy alcohol include Sanniks GP250 and Sannis GP400 (manufactured by Sanyo Chemical Industries, Ltd.).

The alkyleneoxyalkyl ether is preferably ethyleneoxyalkyl ether having 1 to 4 carbon atoms in the alkyl moiety or propyleneoxyalkyl ether having 1 to 4 carbon atoms in the alkyl moiety.
Examples of the alkylene oxyalkyl ether include ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monobutyl ether, diethylene glycol monomethyl ether, diethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monobutyl ether, dipropylene glycol monomethyl ether. , Triethylene glycol monomethyl ether, ethylene glycol diacetate, ethylene glycol monomethyl ether acetate, triethylene glycol monomethyl ether, triethylene glycol monoethyl ether, ethylene glycol monophenyl ether, and the like.

In addition to the above water-soluble organic solvent, other organic solvents may be contained as necessary from the viewpoint of preventing drying, promoting penetration, adjusting viscosity, and the like.
When an organic solvent is used as an anti-drying agent, nozzle clogging that may occur due to drying of the ink at the ink ejection port can be effectively prevented when recording an image by ejecting water-based ink by the inkjet method. . In order to prevent drying, a water-soluble organic solvent having a vapor pressure lower than that of water is preferable. Specific examples of water-soluble organic solvents suitable for preventing drying include ethylene glycol, propylene glycol, diethylene glycol, polyethylene glycol, thiodiglycol, dithiodiglycol, 2-methyl-1,3-propanediol, 1,2 , 6-hexanetriol, acetylene glycol derivatives, polyhydric alcohols represented by glycerin, trimethylolpropane, etc., 2-pyrrolidone, N-methyl-2-pyrrolidone, 1,3-dimethyl-2-imidazolidinone, N -Heterocycles such as ethylmorpholine, sulfur-containing compounds such as sulfolane, dimethyl sulfoxide and 3-sulfolene, polyfunctional compounds such as diacetone alcohol and diethanolamine, and urea derivatives. Of these, polyhydric alcohols such as glycerin and diethylene glycol are preferred.
Further, in order to promote penetration, an organic solvent may be used for the purpose of allowing the water-based ink to penetrate better into the recording medium. Specific examples of organic solvents suitable for promoting penetration include alcohols such as ethanol, isopropanol, butanol, and 1,2-hexanediol, sodium lauryl sulfate, sodium oleate, and nonionic surfactants.
In addition to the above, the water-soluble organic solvent can be used for adjusting the viscosity. Specific examples of water-soluble organic solvents that can be used to adjust the viscosity include alcohols (eg, methanol, ethanol, propanol, etc.), amines (eg, ethanolamine, diethanolamine, triethanolamine, ethylenediamine, diethylenetriamine, etc.) And other polar solvents (for example, formamide, N, N-dimethylformamide, N, N-dimethylacetamide, dimethyl sulfoxide, sulfolane, 2-pyrrolidone, acetonitrile, acetone, etc.).

(water)
The water-based ink in the present invention contains water, but the amount of water is not particularly limited. Among them, the amount of water is preferably 10% by mass or more and 99% by mass or less, and more preferably 20% by mass or more and 70% by mass with respect to the total mass of the water-based ink from the viewpoint of ensuring stability and ejection reliability. It is as follows.

(Surfactant)
Various surfactants can be used for the water-based ink in the present invention. Among the surfactants, acetylene glycol surfactants are preferable. The acetylene glycol-based surfactant is easy to keep the surface tension and the interfacial tension between the ink-jet head member (head nozzle and the like) in contact with the ink and foam less easily than other surfactants. Therefore, ejection stability when ejecting water-based ink is improved. In addition, the inclusion of an acetylene glycol surfactant improves the wettability and penetrability of the recording medium, suppresses uneven density and blurring of the ink, and is advantageous for fine image formation.

  Examples of the acetylene glycol surfactant include Surfynol 104, 104E, 104H, 104A, 104BC, 104DPM, 104PA, 104PG-50, 104S, 420, 440, 465, 485, SE, SE-F, 504, 61, DF37, CT111, CT121, CT131, CT136, TG, GA (all of which are Air Products and Chemicals. Inc. Orphine B, Y, P, A, STG, SPC, E1004, E1010, PD-001, PD-002W, PD-003, PD-004, EXP. 4001, the same EXP. 4036, EXP. 4051, AF-103, AF-104, AK-02, SK-14, SK-3, AE-3 (all of which are manufactured by Nissin Chemical Industry Co., Ltd.), acetylenol E00, E00P, E40, E100 (all of which are manufactured by Kawaken Fine Chemical Co., Ltd.) and the like.

  The content of the surfactant in the water-based ink is preferably 0.1 to 1.5% by mass and more preferably 0.5 to 1.0% by mass with respect to the total amount of the ink. When the content of the surfactant is 0.1% by mass or more, the ink tends to uniformly spread on the fibers of the recording base material, the image scratch resistance is improved, and the bleeding of the image is suppressed to make the image more uniform. An image is obtained. When the content is 1.5% by mass or less, the storage stability and ejection stability of water ink are excellent.

(2-pyrrolidone)
The aqueous ink of the present invention preferably contains 2-pyrrolidone. 2-Pyrrolidone functions as a wetting agent. By containing 2-pyrrolidone, the permeability is improved, and the effect of expanding the droplet diameter (the length of the ink droplet applied on the fiber in the fiber axis direction) when the ink is applied on the fiber. is there.

  The content of 2-pyrrolidone in the water-based ink is such that it imparts the permeability to the ink and expands the ink droplet diameter (the length of the ink droplet applied on the fiber in the fiber axis direction) to a desired extent. In terms of the total amount of ink, it is preferably 0.5% by mass or more and 50% by mass or less, and more preferably 0.5% by mass or more and 30% by mass or less. Further, from the viewpoint of achieving both the effect of expanding the dot diameter and the image abrasion resistance, 1% by mass or more and 30% by mass or less is particularly preferable.

(Other)
The water-based ink in the present invention can contain other additives in addition to the above-described components as necessary. Other additives include, for example, lubricants, anti-fading agents, emulsion stabilizers, penetration enhancers, ultraviolet absorbers, preservatives, antifungal agents, pH adjusters, surface tension adjusters, antifoaming agents, viscosity adjusters. , Known additives such as dispersants, dispersion stabilizers, rust inhibitors and chelating agents. These various additives may be added directly after preparing the water-based ink, or may be added when preparing the water-based ink.

The water-based ink in the present invention can further contain a lubricant other than wax in addition to the wax particles, from the viewpoint of improving scratch resistance. The lubricant other than wax is not particularly limited as long as it has a function of reducing the friction coefficient of the image surface. Examples of lubricants include ester compounds, silicone compounds, fluorine compounds, higher aliphatic acids or salts thereof, fatty acid amide compounds (preferably carboxylic acid amide compounds), and organic or inorganic matting agents. The details of these lubricants are described in paragraph numbers [0037] to [0041] of JP 2010-155359 A. Among these, silicone oil having a structure of “— (— Si (CH ₃ ) ₂ ) _n —”, 1-pentadecyl-2-hexadecyl-phthalic acid diester, and palmitic acid amide are preferable.

  Details of additives other than the lubricant are described in paragraphs [0098] to [0105] of JP 2010-155359 A.

-Recording substrate-
In the image recording method of the present invention, a recording substrate that is an aggregate of non-ink-absorbing or low-absorbing fiber materials is used. The recording substrate refers to a recording material on which an image is recorded.

Non-absorptivity or low absorptivity indicates the degree of absorption of the water-based ink of the recording substrate, but since the ink is water-based, it can be evaluated by the water absorbency as described below. That is,
In the present invention, “non-absorbable fiber” means a fiber having a composition having a water absorption (mass%, 24 hr.) Of less than 0.2 according to ASTM D570 of ASTM test method. The term “fiber” refers to a fiber having a composition having a water absorption (mass%, 24 hr.) Of 0.2 or more and less than 0.5 according to ASTM D570 of the ASTM test method.

  Examples of non-ink-absorbing or low-absorbing fiber materials include polyolefin fibers (for example, fibers such as polypropylene and polyethylene), polyester fibers (for example, fibers such as polyethylene terephthalate and polyethylene naphthalate), aramid fibers, and cellulose fibers. , Synthetic fibers such as nylon fiber, vinylon fiber and rayon fiber, metal fibers such as stainless steel, iron, gold, silver and aluminum, glass fibers (glass wool and the like), and the like.

  Examples of aggregates of non-ink-absorbing or low-absorbing fiber materials include non-woven fabrics, woven fabrics, and glass wool.

  The said nonwoven fabric means the sheet-like thing intertwined without weaving fiber, and a hydroentangled nonwoven fabric is contained. Nonwoven fabrics are processed sheets, webs, or bats of fibers that are oriented in one direction or randomly and are secured by friction, adhesion, adhesion, or the like. Nonwovens do not include woven or knitted, or tufted, stitchbonded incorporating thread or filament bonds, or felted by wet milling.

  In the present invention, among the above, the nonwoven fabric is preferable, more preferable because it is low in cost, processability, and is relatively weak in scratch resistance of an image and easily causes bleeding, and the effects of the present invention are more exerted. Is a nonwoven fabric of polyolefin fibers.

  The aggregate of fiber materials in the present invention preferably has a diameter (fiber diameter) of a cross section perpendicular to the fiber axis direction of the fibers constituting the recording substrate, more preferably 1 to 100 μm, and particularly preferably 1 to 100 μm. Preferably it is 5-60 micrometers. A fiber diameter of 1 μm or more is advantageous in terms of image abrasion resistance and stiffness of the recording substrate itself, and a fiber diameter of 200 μm or less is advantageous in terms of image bleeding and texture of the recording substrate.

  The thickness of the recording substrate is preferably 1 to 1000 μm, more preferably 1 to 800 μm, still more preferably 5 to 500 μm, and particularly preferably 5 to 300 μm. The thickness of 1 μm or more is advantageous in terms of stiffness of the recording substrate itself, and the thickness of 1000 μm or less is advantageous in terms of texture of the recording substrate.

The density of the recording substrate (fiber areal density), preferably from 1 to 300 g / ^{m 2,} more preferably ^{1~200g / m 2, 5~100g / m} 2 is particularly preferred. A fiber surface density of 1 g / m ² or more is advantageous in that an image density can be easily obtained, and a fiber surface density of 300 g / m ² or less is advantageous in terms of image abrasion resistance and image bleeding.
The fiber surface density refers to the ratio [g / m ² ] of the amount of fibers existing on the surface to the area of the surface on which the fibers are two-dimensionally distributed, and the recording substrate is expressed in unit area. It is a value obtained by cutting out and measuring the weight.

  The recording substrate may be formed by any method such as melt blowing, spun bonding, solvent spinning, electrospinning, carding and the like.

  As a pre-process for the ink application process, a pre-process for performing a hydrophilization process may be provided on the recording substrate. In the present invention, a configuration using a plurality of polymer particles is used. As a result, the desired image adhesion and scratch resistance can be obtained without providing a pre-processing step or with a small amount of pre-processing. The hydrophilization treatment here includes, for example, corona treatment, plasma treatment, flame treatment, heat treatment, wear treatment, and light irradiation treatment (UV treatment).

The surface tension of the recording substrate is preferably 3.2 × 10 ^{−6 to} 4.5 × 10 ⁻⁶ J (about 32 to 45 dynes / cm), and 3.2 × 10 ^{−6 to} 4.0. × 10 ⁻⁶ J (about 32 to 40 dynes / cm) is more preferable, and 3.2 × 10 ^{−6 to} 3.7 × 10 ⁻⁶ J (about 32 to 37 dynes / cm) is particularly preferable. When the surface tension of the base material is equal to or higher than the lower limit value, image adhesion becomes better, and when the surface tension of the base material is equal to or lower than the upper limit value, the texture of the base material itself can be maintained.
In addition, the surface tension of a base material is measured by using the liquid mixture number at which the base material begins to get wet with a liquid mixture for wet tension test (manufactured by Wako Pure Chemical Industries, Ltd.) as the surface tension of the base material.
In this case, the surface tension of the ink composition is preferably in the range of 20 to 40 mN / m (= dyn / cm), and more preferably in the range of 30 to 40 mN / m. The surface tension of the ink composition is measured by the Wilhelmi method using a static surface tension measuring device (for example, TD3 manufactured by Ikeda Rika Co., Ltd.).

[Dry fixing process]
In the present invention, it is preferable to provide a dry fixing step in which the ink applied to the recording substrate is dried and fixed to the substrate during and / or after applying the aqueous ink in the ink applying step. . That is, the recorded matter obtained by the image recording method of the present invention preferably has an ink image that has undergone a drying process.

  Through the drying and fixing process, the evaporation of the liquid medium in the ink (specifically, water and water-soluble organic solvent) is promoted, and the image is excellent in high-quality images with little unevenness and bleeding and scratch resistance. A recorded matter can be obtained in a short time. Further, the occurrence of wrinkles on the recording base material can be prevented, and further the curling of the recording base material can be prevented. Further, at the time of drying, the heating promotes the fusion of the polymer particles contained in the ink, and a good film is formed, so that the scratch resistance of the recorded matter is further improved.

The drying temperature at the time of drying is not particularly limited as long as the liquid medium present in the ink evaporates and a film formed of polymer particles is formed. Among these, the drying temperature is preferably 40 ° C. or higher and 150 ° C. or lower, more preferably 40 ° C. or higher and 80 ° C. or lower. When the temperature is 80 or less, deformation of the recording substrate can be prevented.
The heating time at the time of drying is not particularly limited as long as the liquid medium in the ink evaporates and a film can be formed by the polymer particles. You can choose.

  The drying method is not particularly limited as long as it is a method for promoting the volatilization of the liquid medium contained in the ink. Examples of the drying method include a method of applying heat to the recording base material before and after recording, a method of blowing air on the recording base material after recording, or a method combining these. Specific examples include forced air heating, radiation heating, conduction heating, high frequency drying, microwave drying, and dry air blowing.

<Recorded image>
The image recorded matter of the present invention is a recording base material that is an aggregate of non-absorbing or low-absorbing fiber materials, and is provided on the recording base material, includes a polyolefin component, and is chlorinated, acrylic, and anhydrous. A polymer a subjected to a modification treatment selected from maleic acid modification, a polymer b having a structural portion different from the polymer a, and an ink image containing a colorant are provided. The image recorded matter of the present invention contains the polymer a and the polymer b, and as described above, the adhesion between the non-ink-absorbing or low-absorbing fiber material is good and excellent. Has scratch resistance.

  The details of the recording base material, which is an aggregate of non-absorbing or low-absorbing fiber materials, the polymers a and b forming the ink image, the colorant, and the like are as described above. The polymer a is the same as the polymer constituting the polymer particle A described above, and the polymer b is the same as the polymer constituting the polymer particle B described above. The polymer in the recorded matter may be contained in the form of polymer particles, or may be contained in a form different from the particles by applying heat through a drying and fixing process.

  The recorded image of the present invention may be recorded by any method capable of obtaining an ink image containing the above components on a non-absorbing or low-absorbing recording substrate. In the present invention, the image recorded matter obtained by the above-described image recording method of the present invention is preferable in that the ink image is excellent in adhesion to the substrate and scratch resistance.

  The thickness of the ink image is not particularly limited, but is preferably 0.1 to 10.0 μm. When the thickness is within the above range, it is advantageous in terms of scratch resistance, adhesion and image texture.

  EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples. However, the present invention is not limited to the following examples unless it exceeds the gist thereof.

Example 1
<Preparation of magenta ink>
(Synthesis of polymer dispersant P-1)
According to the following scheme, a polymer dispersant P-1 was synthesized as shown below.

To a 1000 ml three-necked flask equipped with a stirrer and a condenser tube, 88 g of methyl ethyl ketone was added and heated to 72 ° C. in a nitrogen atmosphere. Here, 50 g of methyl ethyl ketone was mixed with 0.85 g of dimethyl 2,2′-azobisisobutyrate and 60 g of benzyl methacrylate. Then, a solution in which 10 g of methacrylic acid and 30 g of methyl methacrylate were dissolved was dropped over 3 hours. After completion of the dropwise addition, the reaction was further continued for 1 hour, and then a solution of 0.42 g of dimethyl 2,2′-azobisisobutyrate in 2 g of methyl ethyl ketone was added, heated to 78 ° C. and heated for 4 hours. The obtained reaction solution was reprecipitated twice in a large excess amount of hexane, and the precipitated resin was dried to obtain 96 g of a polymer dispersant P-1.
The composition of the obtained polymer dispersant P-1 was confirmed by ¹ H-NMR, and the weight average molecular weight (Mw) determined by GPC was 44,600. Furthermore, when the acid value was calculated | required by the method as described in JIS specification (JIS K0070: 1992), it was 65.2 mgKOH / g.

(Preparation of magenta pigment dispersion)
Pigment Red 122 (CROMOPHTAL Jet Magenta DMQ, manufactured by Ciba Specialty Chemicals Co., Ltd .; magenta pigment), 5 parts of the polymer dispersant P-1, 42 parts of methyl ethyl ketone, 1N NaOH aqueous solution, 5. 5 parts and 87.2 parts of ion-exchanged water were mixed and dispersed with a bead mill for 2 to 6 hours using 0.1 mmφ zirconia beads.
Methyl ethyl ketone was removed from the obtained dispersion under reduced pressure at 55 ° C., and a part of water was further removed. Further, a high-speed centrifugal cooler 7550 (manufactured by Kubota Seisakusho) was used and 8000 rpm using a 50 mL centrifuge tube. For 30 minutes. At this time, the supernatant liquid other than the precipitate was collected. Thereafter, the pigment concentration was determined from the absorbance spectrum, and a dispersion (magenta pigment dispersion) of resin-coated pigment particles (pigment coated with a polymer dispersant) having a pigment concentration of 15% by mass was obtained.

(Preparation of magenta ink)
Components in the following composition were mixed to prepare ink composition A. After the preparation, this ink composition A was packed in a plastic disposable syringe and filtered with a polyvinylidene fluoride (PVDF) pore size 5 μm filter (Millex-SV, Millipore, diameter 25 mm). did.
<Ink composition>
-Magenta pigment dispersion (pigment concentration: 15% by mass) ... 26.7 parts by mass-2-pyrrolidone (manufactured by Tokyo Chemical Industry Co., Ltd.) ... 17 parts by mass-2-methyl-1,3-propanediol- -9 parts by mass-Olfine E1010 (manufactured by Nissin Chemical Industry Co., Ltd.) ... 1 part by mass-Jonkrill 775 ... 10 parts by mass (Johnson Polymer Co., Ltd., styrene / acryl resin particles (Tg: 37 ° C, volume average) 45% by weight dispersion with a particle size of about 80 nm)
-Super Clone E-415 ... 1.7 parts by mass (manufactured by Nippon Paper Chemicals, maleic anhydride modified / chlorinated modified polyolefin resin particles, solid content concentration: 30% by mass, melting point (Tm): 75 to 85 ° C , Weight average molecular weight: 10 to 120,000)
・ Ion-exchanged water: Residue when the total amount of ink is 100 parts by mass (parts by mass)

<Image recording and evaluation>
1. Image recording With respect to polypropylene nonwoven fabric (fiber surface density: 30 g / m ² , thickness: 13 μm, fiber diameter: 20 μm), using a corona master (manufactured by Shinko Electric Meter Co., Ltd., PS-10S), processing voltage: 10 kV, processing Speed: Corona treatment was performed twice under the condition of 50 mm / sec. Using a GELJET GX-5000 printer head for the corona-treated non-woven fabric, the magenta ink prepared as described above is 85 pl, 100% of 200 dpi using a Q-class head (F-Film Dimatix, Q-Class). A solid image was recorded (ink application process). This solid image was brought into intimate contact with a nylon mesh platform, and dried and fixed by applying a warm air with a wind speed of 7 m / s and a temperature of 40 ° C. for 30 seconds with a dryer from the non-image forming surface side of the nonwoven fabric (dry fixing step). In this way, an image sample was obtained.

2. Measurement / Evaluation The following measurement and evaluation were performed on the image samples obtained as described above. The results of measurement and evaluation are shown in Table 1 below.

-A. Scratch resistance
The image portion of the obtained image sample is rubbed with white cotton using a Gakushin friction tester (manufactured by Yasuda Seiki Co., Ltd., No. 428) and applied with a force of about 2 N with white cotton, and the white portion is rubbed. The color transferred to cotton was visually evaluated according to the following evaluation criteria. Among the evaluation criteria, “A to C” is an allowable range for the scratch resistance.
<Evaluation criteria>
A: Even if rubbed 10 times, almost no color transfer to white cotton is observed, and there is no practical problem.
B: When rubbed back and forth 10 times, a slight color transfer was observed in white cotton, but there was no practical problem.
C: When rubbing with 10 reciprocations, color transfer was observed in white cotton, but when rubbing with 3 reciprocations, there was almost no color transfer, and there was no practical problem.
D: When reciprocated three times, color transfer is observed in white cotton, which impedes practical use.
E: A clear color transfer is observed in white cotton after rubbing three times.

-B. Adhesiveness
The image portion of the obtained image sample was subjected to a peeling test with a tape, and the tape was observed with a loupe to observe whether the image was peeled off from the substrate. At this time, even if the fiber to which the ink was applied was peeled off from the tape used, if the peeling of the ink itself was not observed, the ink was not peeled off. Among the evaluation criteria, “A to B” is an allowable range for the adhesion.
<Evaluation criteria>
A: Even if the adhesion test is performed with a gummed tape, the ink peeled on the tape is not observed.
B: When an adhesion test is performed with a gummed tape, ink slightly peeled on the tape is observed, but no ink peeling is observed with the cellophane tape.
C: When the adhesion test is performed with a cellophane tape, slight ink peeling is observed, but no ink peeling is observed with the mending tape.
D: When an adhesion test is performed with a mending tape, ink peeling is observed.

(Example 2)
In Example 1, a magenta ink was prepared, and image recording and evaluation were performed in the same manner as in Example 1 except that the ink composition was changed to the following.
<Ink composition>
-Magenta pigment dispersion (pigment concentration: 15% by mass) ... 26.7 parts by mass-2-pyrrolidone (manufactured by Tokyo Chemical Industry Co., Ltd.) ... 17 parts by mass-2-methyl-1,3-propanediol- · 9 parts by mass · Olphin E1010 (manufactured by Nissin Chemical Industry Co., Ltd.) ··· 1 part by mass · Acryt WBR-016U · · 15 parts by mass (made by Taisei Fine Chemical Co., Ltd., polyurethane resin particles (Tg: 20 ° C, volume average particle) 30% by weight dispersion (diameter: about 30 nm)
-Super Clone E-415 ... 1.7 parts by mass (manufactured by Nippon Paper Chemicals, maleic anhydride modified / chlorinated modified polyolefin resin particles, solid content concentration: 30% by mass, melting point (Tm): 75 to 85 ° C , Weight average molecular weight: 10 to 120,000)
・ Ion-exchanged water: Residue when the total amount of ink is 100 parts by mass (parts by mass)

(Example 3)
In Example 1, a magenta ink was prepared, and image recording and evaluation were performed in the same manner as in Example 1 except that the ink composition was changed to the following.
<Ink composition>
-Magenta pigment dispersion (pigment concentration: 15% by mass) ... 26.7 parts by mass-2-pyrrolidone (manufactured by Tokyo Chemical Industry Co., Ltd.) ... 17 parts by mass-2-methyl-1,3-propanediol- · 9 parts by mass · Olphin E1010 (manufactured by Nissin Chemical Industry Co., Ltd.) ··· 1 part by mass · Acryt WBR-016U · · 15 parts by mass (made by Taisei Fine Chemical Co., Ltd., polyurethane resin particles (Tg: 20 ° C, volume average particle) 30% by weight dispersion (diameter: about 30 nm)
-Super Clone E-415 ... 1.7 parts by mass (manufactured by Nippon Paper Chemicals, maleic anhydride modified / chlorinated modified polyolefin resin particles, solid content concentration: 30% by mass, melting point (Tm): 75 to 85 ° C , Weight average molecular weight: 10 to 120,000)
・ Cerosol 524 6.7 parts by mass (manufactured by Chukyo Yushi Co., Ltd., 30% by mass dispersion of carnauba wax particles (Tm: 83 ° C., volume average particle size: about 80 μm), molecular weight: 818)
・ Ion-exchanged water: Residue when the total amount of ink is 100 parts by mass (parts by mass)

Example 4
In Example 1, a magenta ink was prepared, and image recording and evaluation were performed in the same manner as in Example 1 except that the ink composition was changed to the following.
<Ink composition>
-Magenta pigment dispersion (pigment concentration: 15% by mass) ... 26.7 parts by mass-2-pyrrolidone (manufactured by Tokyo Chemical Industry Co., Ltd.) ... 17 parts by mass-2-methyl-1,3-propanediol- · 9 parts by mass · Olphin E1010 (manufactured by Nissin Chemical Industry Co., Ltd.) ··· 1 part by mass · Acryt WBR-016U · · 15 parts by mass (made by Taisei Fine Chemical Co., Ltd., polyurethane resin particles (Tg: 20 ° C, volume average particle) 30% by weight dispersion (diameter: about 30 nm)
Aurolen AE-301 1.7 parts by mass (manufactured by Nippon Paper Chemical Co., Ltd., maleic anhydride / acrylic modified polyolefin resin particles, solid content concentration: 30% by mass, melting point (Tm): 60 to 70 ° C., weight (Average molecular weight: 80-100,000)
・ Cerosol 524 6.7 parts by mass (manufactured by Chukyo Yushi Co., Ltd., 30% by mass dispersion of carnauba wax particles (Tm: 83 ° C., volume average particle size: about 80 μm), molecular weight: 818)
・ Ion-exchanged water: Residue when the total amount of ink is 100 parts by mass (parts by mass)

(Example 5)
In Example 1, a magenta ink was prepared, and image recording and evaluation were performed in the same manner as in Example 1 except that the ink composition was changed to the following.
<Ink composition>
-Magenta pigment dispersion (pigment concentration: 15% by mass) ... 26.7 parts by mass-2-pyrrolidone (manufactured by Tokyo Chemical Industry Co., Ltd.) ... 17 parts by mass-2-methyl-1,3-propanediol- · 9 parts by mass · Olphin E1010 (manufactured by Nissin Chemical Industry Co., Ltd.) ··· 1 part by mass · Acryt WBR-016U · · 15 parts by mass (made by Taisei Fine Chemical Co., Ltd., polyurethane resin particles (Tg: 20 ° C, volume average particle) 30% by weight dispersion (diameter: about 30 nm)
Aurolen S-6375: 1.7 parts by mass (manufactured by Nippon Paper Chemical Co., Ltd., maleic anhydride / acrylic modified polyolefin resin particles, solid content concentration: 30% by mass, melting point (Tm): 80 to 90 ° C., weight (Average molecular weight: 10-120,000)
・ Cerosol 524 6.7 parts by mass (manufactured by Chukyo Yushi Co., Ltd., 30% by mass dispersion of carnauba wax particles (Tm: 83 ° C., volume average particle size: about 80 μm), molecular weight: 818)
・ Ion-exchanged water: Residue when the total amount of ink is 100 parts by mass (parts by mass)

(Example 6)
In Example 4, image recording and evaluation were performed in the same manner as in Example 1 except that magenta ink was ejected using DMP (manufactured by FUJIFILM Dimatix) at a drop volume of 10 pl.

(Example 7)
In Example 4, image recording and evaluation were performed in the same manner as in Example 1 except that magenta ink was ejected using DMP (manufactured by FUJIFILM Dimatix) at a droplet volume of 40 pl.

(Example 8)
In Example 4, image recording and evaluation were performed in the same manner as in Example 1 except that magenta ink was ejected using DMP (manufactured by Fujifilm Dimatix) at a drop volume of 60 pl.

Example 9
In Example 4, image recording and evaluation were performed in the same manner as in Example 1 except that magenta ink was ejected using DMP (manufactured by Fujifilm Dimatix) at a drop amount of 120 pl.

(Example 10)
In Example 4, image recording and evaluation were performed in the same manner as in Example 1 except that magenta ink was ejected with a drop amount of 150 pl using DMP (manufactured by Fujifilm Dimatix).

(Example 11)
In Example 1, a magenta ink was prepared, and image recording and evaluation were performed in the same manner as in Example 1 except that the ink composition was changed to the following.
<Ink composition>
-Magenta pigment dispersion (pigment concentration: 15% by mass) ... 26.7 parts by mass-2-pyrrolidone (manufactured by Tokyo Chemical Industry Co., Ltd.) ... 17 parts by mass-2-methyl-1,3-propanediol- -9 parts by mass-Olfin E1010 (manufactured by Nissin Chemical Industry Co., Ltd.) ... 1 part by mass-Vylonal MD1480 ... 18 parts by mass (Toyobo Co., Ltd., 30% by mass dispersion of polyester resin particles (Tg: 20 ° C) )
Aurolen AE-301 1.7 parts by mass (manufactured by Nippon Paper Chemical Co., Ltd., maleic anhydride / acrylic modified polyolefin resin particles, solid content concentration: 30% by mass, melting point (Tm): 60 to 70 ° C., weight (Average molecular weight: 80-100,000)
・ Cerosol 524 6.7 parts by mass (manufactured by Chukyo Yushi Co., Ltd., 30% by mass dispersion of carnauba wax particles (Tm: 83 ° C., volume average particle size: about 80 μm), molecular weight: 818)
・ Ion-exchanged water: Residue when the total amount of ink is 100 parts by mass (parts by mass)

(Example 12)
In Example 1, a magenta ink was prepared, and image recording and evaluation were performed in the same manner as in Example 1 except that the ink composition was changed to the following.
<Ink composition>
-Magenta pigment dispersion (pigment concentration: 15% by mass) ... 26.7 parts by mass-2-pyrrolidone (manufactured by Tokyo Chemical Industry Co., Ltd.) ... 17 parts by mass-2-methyl-1,3-propanediol- · 9 parts by mass · Olphin E1010 (manufactured by Nissin Chemical Industry Co., Ltd.) ··· 1 part by mass · Acryt WBR-016U · · 15 parts by mass (made by Taisei Fine Chemical Co., Ltd., polyurethane resin particles (Tg: 20 ° C, volume average particle) 30% by weight dispersion (diameter: about 30 nm)
・ Supercron E723 ... 1.7 parts by mass (Nippon Paper Chemical Co., Ltd., chlorinated modified polyolefin resin particles, solid content concentration: 30% by mass)
・ Cerosol 524 6.7 parts by mass (manufactured by Chukyo Yushi Co., Ltd., 30% by mass dispersion of carnauba wax particles (Tm: 83 ° C., volume average particle size: about 80 μm), molecular weight: 818)
・ Ion-exchanged water: Residue when the total amount of ink is 100 parts by mass (parts by mass)

(Example 13)
In Example 1, a magenta ink was prepared, and image recording and evaluation were performed in the same manner as in Example 1 except that the ink composition was changed to the following.
<Ink composition>
-Magenta pigment dispersion (pigment concentration: 15% by mass) ... 26.7 parts by mass-2-pyrrolidone (manufactured by Tokyo Chemical Industry Co., Ltd.) ... 17 parts by mass-2-methyl-1,3-propanediol- · 9 parts by mass · Olphin E1010 (manufactured by Nissin Chemical Industry Co., Ltd.) ··· 1 part by mass · Acryt WBR-016U · · 15 parts by mass (made by Taisei Fine Chemical Co., Ltd., polyurethane resin particles (Tg: 20 ° C, volume average particle) 30% by weight dispersion (diameter: about 30 nm)
Harden NA-3002: 1.7 parts by mass (manufactured by Toyobo Co., Ltd., maleic anhydride-modified polyolefin resin particles, solid content concentration: 30% by mass)
・ Cerosol 524 6.7 parts by mass (manufactured by Chukyo Yushi Co., Ltd., 30% by mass dispersion of carnauba wax particles (Tm: 83 ° C., volume average particle size: about 80 μm), molecular weight: 818)
・ Ion-exchanged water: Residue when the total amount of ink is 100 parts by mass (parts by mass)

(Example 14)
In Example 1, a magenta ink was prepared, and image recording and evaluation were performed in the same manner as in Example 1 except that the ink composition was changed to the following.
<Ink composition>
-Magenta pigment dispersion (pigment concentration: 15% by mass) ... 26.7 parts by mass-2-pyrrolidone (manufactured by Tokyo Chemical Industry Co., Ltd.) ... 17 parts by mass-2-methyl-1,3-propanediol- · 9 parts by mass · Olphin E1010 (manufactured by Nissin Chemical Industry Co., Ltd.) ··· 1 part by mass · Acryt WBR-016U · · 15 parts by mass (made by Taisei Fine Chemical Co., Ltd., polyurethane resin particles (Tg: 20 ° C, volume average particle) 30% by weight dispersion (diameter: about 30 nm)
・ Zaixen L: 2.1 parts by mass (manufactured by Sumitomo Seika Co., Ltd., acrylic-modified polyolefin resin particles, solid content concentration: 24% by mass, melting point (Tm): 90 to 100 ° C., weight average molecular weight: 67,000 )
・ Cerosol 524 6.7 parts by mass (manufactured by Chukyo Yushi Co., Ltd., 30% by mass dispersion of carnauba wax particles (Tm: 83 ° C., volume average particle size: about 80 μm), molecular weight: 818)
・ Ion-exchanged water: Residue when the total amount of ink is 100 parts by mass (parts by mass)

(Example 15)
In Example 1, a magenta ink was prepared, and image recording and evaluation were performed in the same manner as in Example 1 except that the ink composition was changed to the following.
<Ink composition>
-Magenta pigment dispersion (pigment concentration: 15% by mass) ... 26.7 parts by mass-2-pyrrolidone (manufactured by Tokyo Chemical Industry Co., Ltd.) ... 17 parts by mass-2-methyl-1,3-propanediol- · 9 parts by mass · Olphin E1010 (manufactured by Nissin Chemical Industry Co., Ltd.) ··· 1 part by mass · Acryte WBR-016U · · · 11.7 parts by mass (made by Taisei Fine Chemicals, polyurethane resin particles (Tg: 20 ° C, volume 30% by weight dispersion with an average particle size of about 30 nm)
Aurolen AE-301: 5 parts by mass (manufactured by Nippon Paper Chemical Co., Ltd., maleic anhydride / acrylic modified polyolefin resin particles, solid content concentration: 30% by mass, melting point (Tm): 60 to 70 ° C., weight average molecular weight : 80-100,000)
・ Cerosol 524 6.7 parts by mass (manufactured by Chukyo Yushi Co., Ltd., 30% by mass dispersion of carnauba wax particles (Tm: 83 ° C., volume average particle size: about 80 μm), molecular weight: 818)
・ Ion-exchanged water: Residue when the total amount of ink is 100 parts by mass (parts by mass)

(Example 16)
In Example 1, a magenta ink was prepared, and image recording and evaluation were performed in the same manner as in Example 1 except that the ink composition was changed to the following.
<Ink composition>
-Magenta pigment dispersion (pigment concentration: 15% by mass) ... 26.7 parts by mass-2-pyrrolidone (manufactured by Tokyo Chemical Industry Co., Ltd.) ... 17 parts by mass-2-methyl-1,3-propanediol- · 9 parts by mass · Olphin E1010 (manufactured by Nissin Chemical Industry Co., Ltd.) ··· 1 part by mass · Acryte WBR-016U · · · 8.3 parts by mass (made by Taisei Fine Chemical, polyurethane resin particles (Tg: 20 ° C, volume) 30% by weight dispersion with an average particle size of about 30 nm)
・ Aurolen AE-301 8.3 parts by mass (manufactured by Nippon Paper Chemicals Co., Ltd., maleic anhydride / acrylic modified polyolefin resin particles, solid content concentration: 30% by mass, melting point (Tm): 60 to 70 ° C., weight (Average molecular weight: 80-100,000)
・ Cerosol 524 6.7 parts by mass (manufactured by Chukyo Yushi Co., Ltd., 30% by mass dispersion of carnauba wax particles (Tm: 83 ° C., volume average particle size: about 80 μm), molecular weight: 818)
・ Ion-exchanged water: Residue when the total amount of ink is 100 parts by mass (parts by mass)

(Example 17)
In Example 1, a magenta ink was prepared, and image recording and evaluation were performed in the same manner as in Example 1 except that the ink composition was changed to the following.
<Ink composition>
-Magenta pigment dispersion (pigment concentration: 15% by mass) ... 26.7 parts by mass-2-pyrrolidone (manufactured by Tokyo Chemical Industry Co., Ltd.) ... 17 parts by mass-2-methyl-1,3-propanediol- · 9 parts by mass · Olphin E1010 (manufactured by Nissin Chemical Industry Co., Ltd.) ··· 1 part by mass · Acryt WBR-016U · · 16.6 parts by mass (made by Taisei Fine Chemicals, polyurethane resin particles (Tg: 20 ° C, volume) 30% by weight dispersion with an average particle size of about 30 nm)
Aurolen AE-301 0.8 parts by mass (manufactured by Nippon Paper Chemical Co., Ltd., maleic anhydride / acrylic modified polyolefin resin particles, solid content concentration: 30% by mass, melting point (Tm): 60 to 70 ° C., weight (Average molecular weight: 80-100,000)
・ Cerosol 524 6.7 parts by mass (manufactured by Chukyo Yushi Co., Ltd., 30% by mass dispersion of carnauba wax particles (Tm: 83 ° C., volume average particle size: about 80 μm), molecular weight: 818)
・ Ion-exchanged water: Residue when the total amount of ink is 100 parts by mass (parts by mass)

(Example 18)
In Example 1, a magenta ink was prepared, and image recording and evaluation were performed in the same manner as in Example 1 except that the ink composition was changed to the following.
<Ink composition>
-Magenta pigment dispersion (pigment concentration: 15% by mass) ... 26.7 parts by mass-2-pyrrolidone (manufactured by Tokyo Chemical Industry Co., Ltd.) ... 17 parts by mass-2-methyl-1,3-propanediol- · 9 parts by mass · Olphin E1010 (manufactured by Nissin Chemical Industry Co., Ltd.) ··· 1 part by mass · Acrit WBR-016U · · 13.3 parts by mass (made by Taisei Fine Chemicals, polyurethane resin particles (Tg: 20 ° C, volume) 30% by weight dispersion with an average particle size of about 30 nm)
Super Clon E-415 3.3 parts by mass (manufactured by Nippon Paper Chemicals, maleic anhydride modified / chlorinated modified polyolefin resin particles, solid content concentration: 30% by mass, melting point (Tm): 75 to 85 ° C. , Weight average molecular weight: 10 to 120,000)
・ Cerosol 524 3.4 parts by mass (manufactured by Chukyo Yushi Co., Ltd., 30% by weight dispersion of carnauba wax particles (Tm: 83 ° C., volume average particle size: about 80 μm), molecular weight: 818)
・ Ion-exchanged water: Residue when the total amount of ink is 100 parts by mass (parts by mass)

(Comparative Example 1)
In Example 1, a magenta ink was prepared, and image recording and evaluation were performed in the same manner as in Example 1 except that the ink composition was changed to the following.
<Ink composition>
-Magenta pigment dispersion (pigment concentration: 15% by mass) ... 26.7 parts by mass-2-pyrrolidone (manufactured by Tokyo Chemical Industry Co., Ltd.) ... 17 parts by mass-2-methyl-1,3-propanediol- · 9 parts by mass · Olphine E1010 (manufactured by Nissin Chemical Industry Co., Ltd.) ··· 1 part by mass · Jonkrill 775 ··· 11.1 parts by mass (manufactured by Johnson Polymer Co., Ltd., styrene / acryl resin particles (Tg: 37 ° C, 45% by mass dispersion of volume average particle size: about 80 nm)
・ Ion-exchanged water: Residue when the total amount of ink is 100 parts by mass (parts by mass)

(Comparative Example 2)
In Example 1, a magenta ink was prepared, and image recording and evaluation were performed in the same manner as in Example 1 except that the ink composition was changed to the following.
<Ink composition>
-Magenta pigment dispersion (pigment concentration: 15% by mass) ... 26.7 parts by mass-2-pyrrolidone (manufactured by Tokyo Chemical Industry Co., Ltd.) ... 17 parts by mass-2-methyl-1,3-propanediol- -9 parts by mass-Olfine E1010 (manufactured by Nissin Chemical Industry Co., Ltd.) ... 1 part by mass-Jonkrill 775 ... 10 parts by mass (Johnson Polymer Co., Ltd., styrene / acryl resin particles (Tg: 37 ° C, volume average) 45% by weight dispersion with a particle size of about 80 nm)
-Chemipearl WP100 ... 1.25 parts by mass (manufactured by Mitsui Chemicals, polypropylene, solid content concentration: 40% by mass)
・ Cerosol 524 6.7 parts by mass (manufactured by Chukyo Yushi Co., Ltd., 30% by mass dispersion of carnauba wax particles (Tm: 83 ° C., volume average particle size: about 80 μm), molecular weight: 818)
・ Ion-exchanged water: Residue when the total amount of ink is 100 parts by mass (parts by mass)

As shown in Table 1, in the examples, compared with the comparative examples, the non-absorbent or low-absorbent recording base material is excellent in image scratch resistance and shows good adhesion. It was.
On the other hand, since the specific polymer particle A was not used together in the comparative example, the desired adhesion could not be obtained and the scratch resistance was poor.

  In the above-described embodiment, the description has been made mainly on the case where the recording substrate is subjected to the corona treatment. The same effect can be obtained even when processing is performed.

The present invention can be applied to any application for recording an image on a base material that is an aggregate of non-absorbent or low-absorbent fiber materials. For example, it is suitable for uses (such as diapers (including disposable pants), hygiene articles such as training pants, incontinence underwear for adults, etc.) using nonwoven fabric as an aggregate of non-absorbable or low-absorbent fiber materials.
The above-mentioned “diaper” refers to an absorbent article generally worn around the lower torso so as to surround the waist and legs of a wearer by an infant or a person with incontinence symptoms and can receive urine, defecation, etc. .

11 ... ink droplet 13 ... fiber (nonwoven fabric)
15, 25 ... Ink adhesion area 23 ... Recording paper (sheet)

Claims (15)

  Contains a colorant, a polymer particle A containing a polyolefin component and subjected to a modification treatment selected from chlorination modification, acrylic modification, and maleic anhydride modification, and a polymer particle B having a different structure from the polymer particle A An image recording method comprising an ink application step of applying an ink composition to be applied onto a recording substrate which is an aggregate of non-absorbing or low-absorbing fiber materials by an ink jet method.   The image recording method according to claim 1, wherein the polymer particle B has a polymer structure excluding a polyolefin structure as a polymer skeleton.   The image recording method according to claim 1, wherein the polymer particles B are resin particles selected from an acrylic resin, a urethane resin, an ester resin, and a styrene resin.   The content ratio (A: B) of the polymer particles A and the polymer particles B is in the range of 0.1: 9.9 to 3: 7 in terms of mass ratio. The image recording method described in 1.   The image recording method according to claim 1, wherein the ink composition further contains wax particles having a melting point of 50 ° C. or higher and 150 ° C. or lower.   The image recording method according to claim 1, wherein a glass transition point of the polymer particle B is 5 ° C. or more and 60 ° C. or less.   The image recording method according to claim 1, wherein the polymer particles A have a weight average molecular weight of 3000 or more.   The image recording method according to claim 1, wherein in the ink application step, the ink composition is applied to the recording substrate with an ink droplet amount of 60 pl or more and 120 pl or less.   The image recording method according to any one of claims 1 to 8, further comprising a dry fixing step of drying and fixing the ink composition applied in the ink applying step to the recording substrate.   The pretreatment step of performing a pretreatment selected from the group consisting of corona treatment, plasma treatment, flame treatment, heat treatment, wear treatment, and light irradiation treatment on the recording substrate before the ink application step. The image recording method according to any one of claims 1 to 9.   The image recording method according to any one of claims 5 to 10, wherein the wax particles have a weight average molecular weight or a molecular weight of less than 3000.   The total amount of the polymer particles A and the polymer particles B is 0.1% or more and 20% or less by mass ratio with respect to the total amount of the ink composition. The image recording method as described. A recording substrate that is an aggregate of non-absorbent or low-absorbent fiber materials;
A polymer a containing a polyolefin component and subjected to a modification treatment selected from chlorination modification, acrylic modification, and maleic anhydride modification, a polymer b having a structural portion different from the polymer a, and an ink image containing a colorant;
A recorded image having   14. The recorded image according to claim 13, wherein the polymer b has a polymer structure excluding a polyolefin structure as a polymer skeleton.   The image recorded matter according to claim 13 or 14, wherein the polymer b includes a resin component selected from an acrylic resin, a urethane resin, an ester resin, and a styrene resin.