Image forming method and processing liquid set

Abstract

To provide an image formation method which can impart a formed image having sufficient water resistance (wet friction fastness) without impairing feeling of a fabric.SOLUTION: An image formation method includes the steps of: imparting a first post treatment liquid containing 2 mass% or more of a water-swellable resin (A) and water onto a fabric, and forming a coated film; and imparting a second post treatment liquid containing a water-swelling inhibitor (B) and water onto the coated film. On the surface of the coated film, the water-swelling inhibitor (B) lowers a water-swelling degree of the water-swellable resin (A) by reaction or interaction with the water-swellable resin (A).SELECTED DRAWING: None

Description

Technical Field

[0001] The present invention relates to an image forming method, an image formed product, and a treatment liquid set.

Background Art

[0002] As methods for forming an image on fabrics such as woven fabrics and non-woven fabrics, there are a screen printing method, a roller printing method, etc. In recent years, studies have been underway on an inkjet printing method that can perform printing substantially plate-free by performing image processing with a computer.

[0003] As coloring materials for printing inks, there are dyes and pigments. Inks using dyes have advantages such as good color development and high dyeing fastness because they utilize the reaction with the functional groups of fibers. On the other hand, post-treatments such as a steaming process for fixing the dye and a process for removing unfixed dye are required, and the workload of these operations has become a problem.

[0004] On the other hand, inks using pigments are preferred for their simplicity compared to dyes because they can form images with high light resistance and do not require post-treatments such as a process for removing unfixed dye. Inks using pigments require a binder component for fixing the pigment. In inkjet printing, there are restrictions on the addition amount of the binder component from the viewpoints of the viscosity and ejection property of the ink, so pigment fixing property and fastness have become problems.

[0005] In contrast, Patent Document 1 proposes a method for manufacturing a printed product including a step of printing a fabric with an ink, a step of applying a middle coat agent containing a resin (C) having a film elongation of 400 to 1500%, and a step of applying an overcoat agent containing a resin (D) having a film elongation of 100 to 400%. Patent Document 2 proposes a coating method including a step of applying an inkjet overcoat liquid containing a urethane resin (aqueous dispersion resin), a blocked isocyanate compound (crosslinking component), a water-soluble organic solvent, and water to a fabric to which ink has been applied.

Prior Art Documents

Patent Document

[0006]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0007] However, since the overcoat liquid of Patent Document 2 involves a crosslinking reaction of the resin, the resulting overcoat layer tends to be hard, and the texture of the fabric is likely to be impaired. Patent Document 1 uses a middle coat agent and an overcoat agent in combination, but the water resistance (wet rubbing fastness) of the resulting image-forming product is not sufficient.

[0008] The present invention has been made in view of the above circumstances, and an object thereof is to provide an image-forming method, an image-forming product, and a treatment liquid set used therefor, which can impart an image-forming product having sufficient water resistance (wet rubbing fastness) without impairing the texture of the fabric.

Means for Solving the Problems

[0009] The image-forming method of the present invention includes a step of applying a first post-treatment liquid containing a water-swellable resin (A) of 2% by mass or more and water onto a fabric to form a coating film, and a step of applying a second post-treatment liquid containing a water-swellability inhibitor (B) and water onto the surface of the coating film, wherein on the surface of the coating film, the water-swellability inhibitor (B) reacts or interacts with the water-swellable resin (A) to reduce the water-swellability of the water-swellable resin (A).

[0010] The image-forming product of the present invention includes a fabric, a first treatment layer containing a water-swellable resin (A), and a second treatment layer containing a water-swellable resin (A) whose water-swellability has been reduced by the reaction or interaction with a water-swellability inhibitor (B) in this order.

[0011] The treatment liquid set of the present invention is a treatment liquid set used for inkjet printing, and includes a first post-treatment liquid containing a water-swellable resin (A) at 2% by mass or more and water, and a water-swellable resin (A) that reacts or interacts with the water-swellable resin (A) to reduce the water swelling degree of the water-swellable resin (A). It includes a water swelling inhibitor (B) and a second post-treatment liquid containing water.

Advantages of the Invention

[0012] According to the present invention, it is possible to provide an image forming method, an image formed product having sufficient water resistance (wet rubbing fastness) without impairing the texture of the fabric, and a treatment liquid set used therefor.

Embodiments for Carrying Out the Invention

[0013] As a result of intensive studies, the present inventors have found that a second post-treatment liquid containing a water swelling inhibitor (B) is applied to the surface of the coating film of the first post-treatment liquid (Processing liquid) containing the water-swellable resin (A), and by reacting or interacting the water swelling inhibitor (B), it is possible to form a layer with a low degree of water swelling on the surface of the coating film. Thereby, it has been found that the wet rubbing fastness can be improved without impairing the texture of the fabric. (Post-treatment liquid) Although this mechanism is not clear, it is presumed as follows. The coating film (for example, the first treatment layer) of the first post-treatment liquid containing the water-swellable resin (A) is relatively flexible, so it is difficult to impair the texture of the fabric. In addition, the layer (for example, the second treatment layer) formed by applying the second post-treatment liquid to the surface of the coating film contains a water-swellable resin (A) whose degree of water swelling has decreased due to a reaction with the water swelling inhibitor (B), etc., so it can have good wet rubbing fastness. Thereby, the wet rubbing fastness can be improved without impairing the texture of the fabric. Hereinafter, the configuration of the present invention will be described.

[0014] Although this mechanism is not clear, it is presumed as follows. The coating film (for example, the first treatment layer) of the first post-treatment liquid containing the water-swellable resin (A) is relatively flexible, so it is difficult to impair the texture of the fabric. Also, the layer (for example, the second treatment layer) formed by applying and forming the second post-treatment liquid on the surface of the coating film contains a water-swellable resin (A) whose water swelling degree has decreased due to a reaction with the water swelling inhibitor (B) or the like, so it can have good wet rubbing fastness. Thereby, the wet rubbing fastness can be increased without impairing the texture of the fabric. Hereinafter, the configuration of the present invention will be described.

[0015] 1. Image Forming Method The image forming method of the present invention includes a step of applying a first post-treatment liquid onto a fabric to form a coating film, and a step of applying a second post-treatment liquid onto the coating film. In the step of applying the second post-treatment liquid, on the surface of the coating film, a water-swellable resin (A) is reacted or interacted with a water-swellability inhibitor (B) to reduce the water-swellability degree of the water-swellable resin (A).

[0016] The fabric may or may not have a coloring material layer formed thereon. In the following embodiments, an example using a fabric with a coloring material layer formed thereon will be described.

[0017] That is, the image forming method according to an embodiment of the present invention may include: 1) a step of forming a coloring material layer on a fabric; 2) a step of applying a first post-treatment liquid onto the coloring material layer to form a coating film; and 3) a step of applying a second post-treatment liquid onto the obtained coating film.

[0018] Step (1) (step of applying ink) The coloring material layer can be formed, for example, by applying ink onto a fabric by an inkjet method and then drying it.

[0019] (Fabric) The fiber material constituting the fabric is not particularly limited, and can be natural fibers such as cotton (cellulose fiber), hemp, wool, and silk, or chemical fibers such as rayon, vinylon, nylon, acrylic, polyurethane, polyester, or acetate. The fabric can be in any form such as a woven fabric, a non-woven fabric, or a knitted fabric made of these fibers. Further, the fabric may be a blended woven fabric or a blended non-woven fabric of two or more types of fibers. The fabric may be pre-treated (see step 4) described later).

[0020] (Application and drying of ink) Next, ink is ejected from an inkjet recording head onto the surface of the fabric to apply ink droplets.

[0021] The ink is an aqueous ink containing a dispersible colorant such as a pigment and water, as described later. From the viewpoint of enhancing the dispersibility of the dispersible colorant, it is preferable that the ink further contains a polymer dispersant or contains a self-dispersible pigment as the dispersible colorant. Details of the ink composition will be described later.

[0022] Then, the ink applied to the fabric is dried and fixed to form a colorant layer. Drying and fixing are preferably performed by heating. That is, the drying method is not particularly limited and can be a method using a heater, a hot air dryer, a heating roller, etc. Among them, it is preferable to heat and dry both sides of the fabric using a hot air dryer and a heater.

[0023] The drying temperature is not particularly limited, but from the viewpoint of sufficiently removing solvent components such as water contained in the applied ink, it is preferably 110°C or higher, and more preferably 130 - 180°C. The drying time depends on the drying temperature, but can be, for example, about 0.5 - 10 minutes.

[0024] Regarding the step (step of applying the first post-treatment liquid) in 2) Next, the first post-treatment liquid is applied onto the obtained colorant layer to form a coating film. In this embodiment, the coating film can protect the colorant layer and impart wet rubbing fastness.

[0025] (First post-treatment liquid) The first post-treatment liquid contains a water-swellable resin (A) and water.

[0026] The "water-swellable property" of the water-swellable resin (A) means the property of swelling with respect to water (the degree of swelling with respect to water is a certain level or higher).

[0027] The degree of water swelling of the water-swellable resin (A) can be measured by the following procedure. 1) A water dispersion of the water-swellable resin (A) is dried and solidified at 70°C and 30 - 35% RH for 48 hours to obtain pellets. Measure the weight of the obtained pellets. 2) Next, the obtained pellets are immersed in ion-exchanged water at 20°C for 5 minutes, and then dried under the same conditions as above to measure the weight. Then, the water swelling degree (%) is calculated by applying the pellet weights before and after immersion in ion-exchanged water to the following formula. Formula (1): Water swelling degree (%) = (Pellet weight after immersion - Pellet weight before immersion) / (Pellet weight before immersion) × 100

[0028] Specifically, the water-swellable resin (A) is a resin having a water swelling degree of 50% or more, preferably 70% or more, more preferably 75 to 100%. A resin whose water swelling degree satisfies the above range not only has appropriate flexibility but also has a bulky group, so it is difficult to penetrate into the interior of the fabric (or the coloring material layer) and tends to stay on the surface of the fabric. Therefore, the fabric is less likely to become hard and the texture is less likely to be impaired.

[0029] The water-swellable resin (A) is not particularly limited as long as it satisfies the above range of water swelling degree and can react or interact with the water swelling inhibitor (B) contained in the second post-treatment liquid described later. That is, the water-swellable resin (A) (contained in the first post-treatment liquid) has a group that can react or interact with the water swelling inhibitor (B) (contained in the second post-treatment liquid), preferably an ionic group.

[0030] The ionic group of the water-swellable resin (A) forms a pair with the ionic group of the water swelling inhibitor (B). That is, it is preferable that the water-swellable resin (A) has an anionic group and the water swelling inhibitor (B) has a cationic group; or the water-swellable resin (A) has a cationic group and the water swelling inhibitor (B) has an anionic group. Among them, it is preferable that the water-swellable resin (A) has an anionic group and the water swelling inhibitor (B) has a cationic group.

[0031] The anionic groups possessed by the water-swellable resin (A) are acidic groups such as carboxyl groups, sulfonyl groups, phosphorus-containing groups (phosphoric acid groups or phosphonic acid groups), and preferably carboxyl groups. Examples of the water-swellable resin (A) having anionic groups include (meth)acrylic resins having anionic groups, urethane resins having anionic groups, vinyl resins having anionic groups, etc., and preferably (meth)acrylic resins having anionic groups.

[0032] The (meth)acrylic resin having anionic groups can be a polymer containing structural units derived from (meth)acrylic monomers having anionic groups. Examples of such monomers include ethylenically unsaturated monomers containing carboxyl groups such as (meth)acrylic acid. Note that (meth)acrylic acid means at least one of acrylic acid and methacrylic acid. The polymer may further contain structural units derived from other copolymerization components such as alkyl (meth)acrylates having 1 to 20 carbon atoms and styrenes.

[0033] Examples of commercially available products include Joncryl PDX-7326 (anionic acrylic emulsion, water swelling degree 76%), urethane resin (Takelac W-6061 manufactured by Mitsui Chemicals, anionic urethane resin emulsion, water swelling degree 88%), etc.

[0034] The acid value of the water-swellable resin (A) having anionic groups is not particularly limited, but can be, for example, 30 to 100 mgKOH / g. When the acid value is within the above range, the water swelling degree is likely to be within the above range. The acid value can be measured by the acid value measurement method of JIS K 0070.

[0035] The content of the water-swellable resin (A) is preferably 2% by mass or more, and more preferably 5 to 20% by mass, based on the first post-treatment liquid. When the content of the water-swellable resin (A) is within the above range, not only can a uniform coating film be formed on the fabric, but also the protective property and fixing property of the colorant layer are excellent.

[0036] The first post-treatment liquid may further contain other components as necessary. Examples of other components include solvents, preservatives, activators, coloring materials, and the like.

[0037] (Solvent) The solvent is not particularly limited, but is preferably a water-soluble organic solvent. The water-soluble organic solvent is not particularly limited as long as it is compatible with water.

[0038] Examples of water-soluble organic solvents include glycerin, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 1,2-pentanediol, 1,3-pentanediol, 1,5-pentanediol, 1,2-hexanediol, 1,6-hexanediol, 1,2,6-hexanetriol, 1,2-heptanediol, 1,2-octanediol, 1,8-octanediol, ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, pentamethylene glycol, trimethylene glycol, 2-butene-1,4-diol, 2-ethyl-1,3-hexanediol, 2-methyl-2,4-pentanediol, dipropylene glycol, tetraethylene glycol, trimethylolpropane, trimethylolethane, and the like. In particular, from the viewpoints of viscosity adjustment, discharge characteristics, and moisturizing function, it is more preferable to use at least one of glycerin, triethylene glycol, propylene glycol, diethylene glycol, and 1,2-hexanediol. These can be used alone or in combination of two or more.

[0039] (Preservative) Examples of preservatives include aromatic halogen compounds (e.g., Preventol CMK), methylene dithiocyanate, halogen-containing nitrogen-sulfur compounds, 1,2-benzisothiazolin-3-one (e.g., PROXEL GXL), and the like.

[0040] (Activator) Examples of activators include surfactants such as acetylene glycol-based surfactants (e.g., Orfin E1010).

[0041] (pH adjuster) Examples of pH adjusters include citric acid, sodium citrate, hydrochloric acid, sodium hydroxide, etc.

[0042] (Colorant) The first post-treatment liquid may further contain a colorant as necessary. When the first post-treatment liquid further contains a colorant, the first post-treatment liquid can also be used as ink. The same colorants as those contained in the ink described later can be used as the colorant.

[0043] The content of the colorant can be 0 to 10% by mass with respect to the first post-treatment liquid. In this embodiment, since the colorant layer is formed by ink, it is preferable that the first post-treatment liquid does not contain a colorant.

[0044] (Application of the first post-treatment liquid) The method of applying the first post-treatment liquid is not particularly limited, and can be, for example, a pad method, a coating method, a spray method, or an inkjet method. Among them, from the viewpoint of being able to apply uniformly in a short time, the pad method is preferable.

[0045] The adhesion amount x (g / m 2 ) of the water-swellable resin (A) by the first post-treatment liquid is not particularly limited as long as it does not impair the texture of the fabric, and can be, for example, such that it can enhance the protectiveness and fixability of the colorant layer. However, it is preferably more than the adhesion amount y (g / m 2 ) of the water-swell prevention agent (B) by the second post-treatment liquid. Specifically, it is preferable that the ratio y / x of the adhesion amount x of the water-swellable resin (A) to the adhesion amount y of the water-swell prevention agent (B) is set within the range described later. More specifically, the adhesion amount x of the water-swellable resin (A) by the first post-treatment liquid can be, for example, 0.2 to 10 g / m 2 , preferably 0.5 to 5 g / m 2 . The adhesion amount x of the water-swellable resin (A) can be calculated, for example, from the composition of the first post-treatment liquid and the adhesion amount of the first post-treatment liquid to the fabric.

[0046] (Drying of the first post-treatment liquid) The drying of the first post-treatment liquid is preferably carried out to such an extent that the solvent component in the first post-treatment liquid evaporates and is removed appropriately to form a film. The drying method is not particularly limited, but it is preferably carried out by heating. The heating method may be the same as described above, and for example, it may be a method using a warm air dryer or a heater.

[0047] The drying temperature is not particularly limited, but it may be such that the solvent in the first post-treatment liquid is removed and a film-like substance is obtained, and for example, it may be 50 to 150 °C. When the solvent contained in the first post-treatment liquid contains a solvent having a boiling point higher than that of water, it is preferable to first evaporate the water at 100 °C or lower and then dry at the highest possible temperature.

[0048] Regarding the step (3) (step of applying the second post-treatment liquid) The second post-treatment liquid is applied onto the obtained coating film. Then, the water swelling inhibitor (B) contained in the second post-treatment liquid is reacted or interacted with the water swellable resin (A) contained in the surface (or surface layer) of the coating film to reduce the water swelling degree of the water swellable resin (A).

[0049] (The second post-treatment liquid) The second post-treatment liquid contains a water swelling inhibitor (B) and water.

[0050] As described above, the water swelling inhibitor (B) reacts or interacts with the water swellable resin (A) to reduce the water swelling degree of the water swellable resin (A). That is, the water swelling inhibitor (B) preferably has an ionic group that forms a pair with the ionic group of the water swellable resin (A), and more preferably has a cationic group that forms a pair with the anionic group of the water swellable resin (A).

[0051] Examples of the cationic group of the water swelling inhibitor (B) include a secondary amino group (imino group), a tertiary amino group, or a quaternary ammonium base.

[0052] The water swelling inhibitor (B) can be an acrylic resin having a cationic group, a polyvalent metal salt, or an organic acid.

[0053] The acrylic resin having a cationic group can be a polymer having a structural unit derived from a (meth)acrylic monomer having a cationic group. Examples of the (meth)acrylic monomer having a cationic group include (meth)acrylate having a cationic group, (meth)acrylamide having a cationic group, and the like.

[0054] Examples of the acrylic resin having a cationic property include cationized poly(meth)acrylate, cationized poly(meth)acrylamide, cationized (meth)acrylate·acrylamide copolymer, cationized methacrylate·methacrylate copolymer, and the like. Examples of commercially available products include the RKW series manufactured by Taisei Fine Chemical Co., Ltd., Vinibran 1008, 1028, 2687 (the above are cationized polyacrylate) manufactured by Nissin Chemical Industry Co., Ltd.; Sumiflock FC-A, Sumiflock FC-B (the above are cationized polymethacrylate) manufactured by Sumitomo Chemical Co., Ltd.; Sunflock C-450, Sunflock C-454 manufactured by Sanyo Chemical Industries, Ltd., Sumiflock FC-L manufactured by Sumitomo Chemical Co., Ltd., Himoro Rock MP series, E series, M-966 (cationized polyacrylamide) manufactured by Himoro Co., Ltd., Sumiflock FC-373, Sumiflock FC-200, Sumiflock FC-C (cationized methacrylate·acrylamide copolymer) manufactured by Sumitomo Chemical Co., Ltd., Sumiflock FC-E (cationized methacrylate·methacrylate copolymer) manufactured by Sumitomo Chemical Co., Ltd.

[0055] The polyvalent metal salt can be a calcium salt, a magnesium salt, or an aluminum salt. These polyvalent metal salts have many reaction points (action points) with the anionic groups of the water-swellable resin (A), and it is easy to obtain a bridging effect (the action of forming a plurality of ionic bonds). Thereby, the degree of water swelling of the water-swellable resin (A) can be reduced on the surface or the surface layer portion of the coating film of the first post-treatment liquid. Among them, the polyvalent metal salt is more preferably a calcium salt or an aluminum salt.

[0056] Examples of polyvalent metal salts include metal salts of inorganic acids such as calcium chloride, magnesium chloride, aluminum chloride, calcium nitrate, magnesium nitrate, and magnesium sulfate.

[0057] Examples of organic acids include citric acid, malic acid, succinic acid, tartaric acid, phthalic acid, glycine, glutamic acid, pyrrolidonecarboxylic acid, pyronecarboxylic acid, pyrrolecarboxylic acid, furancarboxylic acid, pyridinecarboxylic acid, coumaric acid, thiophenecarboxylic acid, nicotinic acid, acetic acid, lactic acid, etc. Among them, lactic acid is preferred.

[0058] Similar to the first post-treatment liquid, the second post-treatment liquid may further contain other components as necessary.

[0059] The content of the water swelling inhibitor (B) can be 0.1 to 10% by mass based on the second post-treatment liquid. When the content of the water swelling inhibitor (B) is within the above range, the second post-treatment liquid has an appropriate low viscosity and is thus suitable for application by, for example, an inkjet method.

[0060] (Application of the second post-treatment liquid) The method for applying the second post-treatment liquid is not particularly limited and can be, for example, a coating method, a spraying method, or an inkjet method. Among them, from the viewpoint of easily forming a thin coating film of the second treatment liquid on the surface (or surface layer) of the coating film of the first post-treatment liquid, the inkjet method is preferred.

[0061] The adhesion amount y (g / m of the water swelling inhibitor (B) by the second post-treatment liquid 2) only needs to be such that the water-swellable resin (A) near the surface of the coating film of the first post-treatment liquid can be modified (the degree of water swelling can be reduced), and is not particularly limited, but it is preferably less than the adhesion amount x of the water-swellable resin (A) by the first post-treatment liquid. Specifically, the mass ratio y / x of the adhesion amount y of the water swelling inhibitor (B) by the second post-treatment liquid to the adhesion amount x of the water-swellable resin (A) by the first post-treatment liquid can be set to be 0.01 or more and less than 1, preferably 0.01 to 0.5, more preferably 0.01 to 0.1. When y / x is within the above range, the layer of the water-swellable resin (A) whose water swelling degree is reduced by the water swelling inhibitor (B) is appropriately thin, so that it is easy to enhance the wet rubbing fastness without impairing the texture. More specifically, the adhesion amount y of the water swelling inhibitor (B) by the second post-treatment liquid depends on its type, but for example, it can be 0.01 to 10 g / m 2 , preferably 0.1 to 5 g / m 2 . The adhesion amount y of the water swelling inhibitor (B) can be calculated, for example, from the composition of the second post-treatment liquid and the adhesion amount of the second post-treatment liquid to the fabric.

[0062] (Drying of the second post-treatment liquid) The drying of the second post-treatment liquid is preferably carried out to such an extent that the solvent component in the second post-treatment liquid is appropriately evaporated and removed to form a film. The drying method is not particularly limited, but it is preferably carried out by heating. The heating method may be the same as described above, and for example, it can be a method using a warm air dryer or a heater.

[0063] The drying temperature only needs to be such that the solvent in the second post-treatment liquid can be removed, and is not particularly limited, but for example, it can be 130 to 180 °C.

[0064] The image forming method of the present invention may further include, if necessary, 4) a step of pretreating the fabric.

[0065] Regarding the step of 4) (pretreating step) The pretreatment can be carried out by applying a pretreatment liquid to the fabric.

[0066] The pretreatment liquid only needs to contain components that enhance the fixing property of the ink on the surface of the fabric, and is not particularly limited. Examples of such components include compounds having an anionic group (such as a carboxyl group, a phosphate group, a phosphonic acid group, and a sulfonic acid group), compounds having a cationic group (such as an amino group and a quaternary ammonium group), and the like.

[0067] Examples of the compound having a cationic group include polyvalent metal salts, resins having a cationic group (such as cationic urethane resins and cationic olefin resins), cationic surfactants, and the like.

[0068] Examples of the compound having an anionic group include resins having an anionic group (such as plant barks such as pectic acid, cellulose derivatives such as carboxymethyl cellulose, modified starches such as carboxymethyl starch and carboxyethyl starch, acrylic polymers having acrylic acid as a copolymerization component such as acrylic acid - acrylic acid ester copolymers and styrene - acrylic acid copolymers), and anionic surfactants.

[0069] The pretreatment liquid may further contain other components such as preservatives and pH adjusters, as described above.

[0070] The method of applying the pretreatment liquid can be the same as described above. The pretreatment liquid applied to the fabric may be dried by heating using warm air, a hot plate, or a heat roller.

[0071] Next, the treatment liquid set or ink set used in the image forming method of the present invention will be described.

[0072] 2. Treatment Liquid Set The treatment liquid set according to an embodiment of the present invention includes a first post - treatment liquid and a second post - treatment liquid.

[0073] In the treatment liquid set according to the present embodiment, the first post-treatment liquid and the second post-treatment liquid are the same as the first post-treatment liquid and the second post-treatment liquid, respectively, in the image forming method according to the present embodiment. That is, the first post-treatment liquid contains a water-swellable resin (A) of 2% by mass or more and water. The second post-treatment liquid contains a water-swellability inhibitor (B) and water. The water-swellability inhibitor (B) contained in the second post-treatment liquid reacts or interacts with the water-swellable resin (A) to reduce the water-swellability degree of the water-swellable resin (A).

[0074] The treatment liquid set may further be an ink set containing ink. That is, the ink set according to the present embodiment further contains ink in addition to the above-mentioned first post-treatment liquid and second post-treatment liquid.

[0075] 2-1. Ink The ink contains a dispersible coloring material and water.

[0076] (1) Dispersible coloring material The dispersible coloring material is not particularly limited and can be a solid dye or pigment such as a disperse dye. Among them, a pigment is preferable from the viewpoint of easily forming an image with excellent weather resistance.

[0077] (Pigment) The pigment is not particularly limited, and can be, for example, an organic pigment or an inorganic pigment of the following numbers described in the Color Index.

[0078] Examples of red or magenta pigments include Pigment Red 3, 5, 19, 22, 31, 38, 43, 48:1, 48:2, 48:3, 48:4, 48:5, 49:1, 53:1, 57:1, 57:2, 58:4, 63:1, 81, 81:1, 81:2, 81:3, 81:4, 88, 104, 108, 112, 122, 123, 144, 146, 149, 166, 168, 169, 170, 177, 178, 179, 184, 185, 208, 216, 226, 257, Pigment Violet 3, 19, 23, 29, 30, 37, 50, 88, Pigment Orange 13, 16, 20, 36.

[0079] Examples of blue or cyan pigments include Pigment Blue 1, 15, 15:1, 15:2, 15:3, 15:4, 15:6, 16, 17-1, 22, 27, 28, 29, 36, 60.

[0080] Examples of green pigments include Pigment Green 7, 26, 36, 50. Examples of yellow pigments include Pigment Yellow 1, 3, 12, 13, 14, 17, 34, 35, 37, 55, 74, 81, 83, 93, 94, 95, 97, 108, 109, 110, 137, 138, 139, 153, 154, 155, 157, 166, 167, 168, 180, 185, 193.

[0081] Examples of black pigments include Pigment Black 7, 28, 26.

[0082] Examples of commercially available pigments include Chromophine Yellow 2080, 5900, 5930, AF-1300, 2700L, Chromophine Orange 3700L, 6730, Chromophine Scarlet 6750, Chromophine Magenta 6880, 6886, 6891N, 6790, 6887, Chromophine Violet RE, Chromophine Red 6820, 6830, Chromophine Blue HS-3, 5187, 5108, 5197, 5085N, SR-5020, 5026, 5050, 4920, 4927, 4937, 4824, 4933GN-EP, 4940, 4973, 5205, 5208, 5214, 5221, 5000P, Chromophine Green 2GN, 2GO, 2G-550D, 5310, 5370, 6830, Chromophine Black A-1103, Seika Fast Yellow 10GH, A-3, 2035, 2054, 2200, 2270, 2300, 2400(B), 2500, 2600, ZAY-260, 2700(B), 2770, Seika Fast Red 8040, C405(F), CA120, LR-116, 1531B, 8060R, 1547, ZAW-262, 1537B, GY, 4R-4016, 3820, 3891, ZA-215, Seika Fast Carmine 6B1476T-7, 1483LT, 3840, 3870, Seika Fast Bordeaux 10B-430, Seika Light Rose R40, Seika Light Violet B800, 7805, Seika Fast Maroon 460N, Seika Fast Orange 900, 2900, Seika Light Blue C718, A612, Cyanine Blue 4933M, 4933GN-EP, 4940, 4973 (manufactured by Dainichi Seika Chemicals); KET Yellow 401, 402, 403, 404, 405, 406, 416, 424, KET Orange 501, KET Red 301, 302, 303, 304, 305, 306, 307, 308, 309, 310, 336, 337, 338, 346, KET Blue 101, 102, 103, 104, 105, 106, 111, 118, 124, KET Green 201 (manufactured by Dainippon Ink and Chemicals).Colortex Yellow 301, 314, 315, 316, P-624, 314, U10GN, U3GN, UNN, UA-414, U263, Finecol Yellow T-13, T-05, Pigment Yellow1705, Colortex Orange 202, Colortex Red101, 103, 115, 116, D3B, P-625, 102, H-1024, 105C, UFN, UCN, UBN, U3BN, URN, UGN, UG276, U456, U457, 105C, USN, Colortex Maroon601, Colortex BrownB610N, Colortex Violet600, Pigment Red 122, ColortexBlue516, 517, 518, 519, A818, P-908, 510, Colortex Green402, 403, Colortex Black 702, U905 (manufactured by Sanyo Pigment); Lionol Yellow1405G, Lionol Blue FG7330, FG7350, FG7400G, FG7405G, ES, ESP-S (manufactured by Toyo Ink), Toner Magenta E02, Permanent RubinF6B, Toner Yellow HG, Permanent Yellow GG-02, Hostapeam BlueB2G (manufactured by Hoechst Industries); Novoperm P-HG, Hostaperm Pink E, Hostaperm Blue B2G (manufactured by Clariant); Carbon Black #2600, #2400, #2350, #2200, #1000, #990, #980, #970, #960, #950, #850, MCF88, #750, #650, MA600, MA7, MA8, MA11, MA100, MA100R, MA77, #52, #50, #47, #45, #45L, #40, #33, #32, #30, #25, #20, #10, #5, #44, CF9 (manufactured by Mitsubishi Chemical) are included.;

[0083] (Self-dispersing pigment) The pigment may be a self-dispersing pigment. A self-dispersing pigment is one in which the surface of the pigment particles is modified with a group having a hydrophilic group, and has pigment particles and a hydrophilic group bonded to the surface thereof.

[0084] Examples of hydrophilic groups include carboxyl groups, sulfonic acid groups, and phosphorus-containing groups. Examples of phosphorus-containing groups include phosphoric acid groups, phosphonic acid groups, phosphinic acid groups, phosphite groups, and phosphate groups.

[0085] Examples of commercially available self-dispersing pigments include Cabot Cab-0-Jet® 200K, 250C, 260M, 270V (sulfonic acid group-containing self-dispersing pigments), Cab-0-Jet® 300K (carboxylic acid group-containing self-dispersing pigments), Cab-0-Jet® 400K, 450C, 465M, 470V, 480V (phosphoric acid group-containing self-dispersing pigments).

[0086] The content of the dispersible colorant is not particularly limited, but from the viewpoint of easily adjusting the viscosity of the ink within the above range and enabling the formation of high-concentration images, it is preferably 1.5 to 15% by mass based on the ink. When the content of the dispersible colorant is 1.5% by mass or more, it is easy to form a high-concentration image, and when it is 15% by mass or less, the viscosity of the ink does not become too high, so the ejection stability is less likely to be impaired. From the same viewpoint, the content of the dispersible colorant is more preferably 5 to 15% by mass based on the ink.

[0087] (2) Other components The ink may further contain other components as necessary. Examples of other components may include solvents other than water, polymer dispersants, binder resins, preservatives, pH adjusters, etc. The solvents, preservatives, and pH adjusters can be the same as those used in the first post-treatment liquid, etc.

[0088] (Polymer dispersant) When the pigment is not a self-dispersing pigment, from the viewpoint of facilitating the dispersion of the pigment, the ink preferably further contains a polymer dispersant. The type of the polymer dispersant is not particularly limited and may be any of cationic dispersants, anionic dispersants, and nonionic dispersants.

[0089] Examples of the cationic groups of the cationic dispersant may include secondary amino groups (imino groups), tertiary amino groups, or quaternary ammonium groups. The cationic dispersant is not particularly limited as long as it can form a pigment dispersion. For example, acrylic (co)polymers having a cationic group (tertiary amino group or quaternary ammonium group) are included.

[0090] The anionic dispersant is a polymer dispersant having a hydrophilic group selected from the group consisting of a carboxylic acid group, a phosphorus-containing group, and a sulfonic acid group. Examples of the polymer dispersant having a carboxylic acid group include polycarboxylic acids or their salts. Examples of the polycarboxylic acids include (co)polymers of monomers selected from acrylic acid or its derivatives, maleic acid or its derivatives, itaconic acid or its derivatives, fumaric acid or its derivatives, and their salts. The polymer dispersant having a phosphorus-containing group is a polymer dispersant having a phosphoric acid group or a phosphonic acid group. Examples of the polymer dispersant having a phosphoric acid group or a phosphonic acid group include alkyl phosphate esters or their salts. Examples of the polymer dispersant having a sulfonic acid group include formalin condensates of aromatic sulfonic acids and formalin condensates of lignin sulfonic acids, preferably formalin condensates of aromatic sulfonic acids. Examples of the formalin condensates of aromatic sulfonic acids include sodium condensed naphthalene sulfonate.

[0091] Examples of the nonionic dispersant include polyoxyalkylene, polyoxyalkylene alkyl ethers, and the like.

[0092] The content of the polymer dispersant is preferably 10 to 50% by mass based on the dispersible colorant. When the content of the polymer dispersant is 10% by mass or more, it is easy to sufficiently enhance the dispersibility of the dispersible colorant, and when it is 50% by mass or less, it is easy to suppress an excessive increase in viscosity. From the same viewpoint, the content of the polymer dispersant is preferably 20 to 40% by mass based on the dispersible colorant.

[0093] (Binder resin) The binder resin can be a water-soluble resin or resin particles (water-dispersible resin). However, from the viewpoint of making it difficult to impair the texture of the fabric of the cloth, it is preferable that the content ratio of the polymer dispersant and the binder resin (especially the content ratio of the binder resin) is small. The content of the binder resin is preferably 5% by mass or less with respect to the ink, and more preferably substantially not contained.

[0094] (3) Physical properties The viscosity of the ink at 25 ° C is not particularly limited as long as the injectability by the inkjet method is good, but it is preferably 3 to 20 mPa·s, and more preferably 4 to 12 mPa·s. The viscosity of the ink can be measured at 25 ° C with an E-type viscometer.

[0095] The ink can be produced through steps of mixing by any method, for example, the above-described dispersible coloring material, water, and any dispersant.

[0096] 3. Image formation The image formation obtained by the image formation method according to an embodiment of the present invention may have a cloth, a coloring material layer, a first treatment layer, and a second treatment layer in this order.

[0097] (Coloring material layer) The coloring material layer is a layer formed by the ink and contains a dispersible coloring material, a polymer dispersant and / or a binder resin. The composition of the coloring material layer is the same as the composition of the solid content of the ink.

[0098] (First treatment layer) The first treatment layer is a layer formed by the first post-treatment liquid and is derived from the above coating film. The first treatment layer can be disposed on the coloring material layer (or the cloth).

[0099] The content of the water-swellable resin (A) in the first treatment layer is preferably 80% by mass or more with respect to the first treatment layer, and more preferably 90 to 100% by mass. When the content of the water-swellable resin (A) is 80% by mass or more, for example, the protectiveness and fixability of the coloring material layer can be sufficiently enhanced.

[0100] The thickness t1 of the first treatment layer is preferably greater than the thickness t2 of the second treatment layer, for example, preferably 1 to 10 μm, and more preferably 2 to 5 μm. When the thickness t1 of the first treatment layer is within the above range, for example, the protectiveness or fixability of the coloring material layer can be enhanced to such an extent that the texture is not impaired.

[0101] (Second treatment layer) The second treatment layer is a layer formed by allowing the coating film of the first post-treatment liquid to act on the second post-treatment liquid, and is disposed on the first treatment layer.

[0102] That is, the second treatment layer contains a water-swellable resin (A) modified with a water-swellability inhibitor (B). The water-swellable resin (A) modified with the water-swellability inhibitor (B) has a lower degree of water swelling than the unmodified water-swellable resin (A).

[0103] The content of the water-swellability inhibitor (B) in the second treatment layer depends on its type, but is preferably, for example, 0.1 to 10% by mass, and more preferably 1 to 5% by mass, based on the second treatment layer. When the content of the water-swellability inhibitor (B) is within the above range, the formed image does not become too hard, so the texture is hardly impaired.

[0104] The thickness t2 of the second treatment layer is preferably smaller than the thickness t1 of the first treatment layer, for example, preferably 5 μm or less, and more preferably 0.2 to 1 μm. Further, the ratio of the thickness t1 of the first treatment layer to the thickness t2 of the second treatment layer can be, for example, t2 / t1 being 0.01 to 1, preferably 0.01 to 0.5. When t2 or t2 / t1 is within the above range respectively, it is easy to enhance the wet rubbing fastness by the second treatment layer without impairing the texture.

[0105] The thickness t1 of the first treatment layer and the thickness t2 of the second treatment layer can be measured by cutting in the thickness direction for each piece of fabric and observing with an electron microscope. Specifically, 1) For the image forming article, in the main scanning direction, samples are taken at both ends and the central part of the sample (for example, at three equally spaced positions), and in the sub-scanning direction, three points (a total of nine points) are sampled at equal intervals (for example, at 5 cm intervals). 2) Next, for each sampled sample, it is cut in a direction parallel to the main scanning direction, and the thickness of the first treatment layer on the cut surface is measured, for example, ten points at a time in the electron microscope image (a total of 90 points), and their average value is taken as the "thickness of the first treatment layer". Note that the main scanning direction is usually the width direction of the image forming article (or fabric). In addition, when the water swelling inhibitor (B) of the second post-treatment liquid is a resin, the interface between the first treatment layer and the second treatment layer can be confirmed by the different colors of the first treatment layer and the second treatment layer in the cross-sectional observation image by an electron microscope. When the water swelling inhibitor (B) is other than a resin, for example, the interface can also be confirmed by further using elemental analysis (such as EDX) in combination.

[0106] The ratio of the adhesion amount x of the water-swellable resin (A) to the adhesion amount y of the water swelling inhibitor (B) in the image forming article is the same as the above mass ratio y / x. The adhesion amount x of the water-swellable resin (A) and the adhesion amount y of the water swelling inhibitor (B) in the image forming article may be converted from the thickness, or can be confirmed by known methods such as elemental analysis (such as ICP), IR, and pyrolysis gas chromatography (pyrolysis GC).

[0107] In the above embodiment, an example of applying the first post-treatment liquid and the second post-treatment liquid on the colorant layer is shown, but it is not limited thereto. For example, the first post-treatment liquid and the second post-treatment liquid may be directly applied on a fabric without a colorant layer. In this case, the first post-treatment liquid may contain a colorant (that is, the first post-treatment liquid may be used as an ink). In this case, the obtained image forming article may not have a colorant layer between the fabric and the first treatment layer.

Examples

[0108] Hereinafter, the present invention will be specifically described by way of examples, but the present invention is not limited thereto.

[0109] <Preparation of Pretreatment Liquid> 3% by mass of calcium chloride, appropriate amounts of preservative, activator, and pH adjuster were added, and the mixture was prepared to 100% by mass with water to obtain a pretreatment liquid.

[0110] <Preparation of Ink> 3% by mass of PR122 of a phosphoric acid self-dispersing pigment, 10% by mass of glycerin, 25% by mass of ethylene glycol, appropriate amounts of preservative, activator, and pH adjuster were added, and the mixture was prepared to 100% by mass with water to obtain ink.

[0111] 1. Preparation of the First Post-treatment Liquid and the Second Post-treatment Liquid <Materials> (Water-swellable Resin (A)) Highly swellable acrylic resin (Joncryl PDX-7326 manufactured by BASF, anionic styrene-acrylic emulsion, water swelling degree 76%, acid value 38 mgKOH / g) Highly swellable urethane resin (Takelac W-6061 manufactured by Mitsui Chemicals, anionic urethane resin emulsion, water swelling degree 88%) (Water Swelling Inhibitor (B)) Cationic acrylic resin (Vinibran 2687 manufactured by Nissin Chemical Industry Co., Ltd., cationized polyacrylate emulsion) Cationic acrylic resin (Hymolock E-395 manufactured by Hymol Co., Ltd., cationized polyacrylamide) Low-swellable acrylic resin (Joncryl PDX-7357 manufactured by BASF, water swelling degree 10%, styrene-acrylic polymer emulsion) The water swelling degree of the resin was measured by the method described below.

[0112] (For Comparison) Superflex 500M (nonionic, urethane resin emulsion) Superflex 150 (anionic, urethane resin emulsion)

[0113] (Preservative) Proxcel GXL(S) manufactured by Lonza

[0114] <Preparation of the First Post-treatment Liquid> Each component was mixed at the composition ratios (mass ratios) shown in Table 1 to prepare post-treatment liquids 1-1 to 1-3 (Examples) and post-treatment liquid 1-4 (Comparative Example).

[0115]

Table 1

[0116] <Preparation of the Second Post-treatment Liquid> Each component was mixed at the composition ratios (mass ratios) shown in Table 2 to prepare post-treatment liquids 2-1, 2-2, 2-4 and 2-5 (Examples) and post-treatment liquids 2-3 and 2-6 (for comparison).

[0117]

Table 2

[0118] 2. Image Formation and Evaluation <Test 1> The prepared pretreatment liquid, ink, post-treatment liquid 1-1 (the first post-treatment liquid) and post-treatment liquid 2-1 (the second post-treatment liquid) were set in a simple printing tester equipped with a KM1024i head as an inkjet head.

[0119] (1) Pretreatment As the fabric, cotton broadcloth 40 (100% cotton) was prepared. The prepared pretreatment liquid was applied to the surface of this fabric by an inkjet method using a simple printing tester so that the adhesion amount of the pretreatment liquid was 15 g / m 2 and then dried at 110°C for 2 minutes. Thereby, a pretreated fabric was obtained.

[0120] (2) Application, Drying and Fixing of Ink Next, the prepared ink was ejected from the nozzles of the inkjet head of a simple printing tester onto the obtained pre-treated fabric to form a 100% solid image of 200 mm × 200 mm. Specifically, an image (200 mm × 200 mm in total) including a thin line grid, gradation, and solid portions was formed at a main scanning of 540 dpi × a sub-scanning of 720 dpi. Dpi represents the number of ink droplets (dots) per 2.54 cm. The ejection frequency was set to 22.4 kHz. The amount of ink adhesion was adjusted so that it became 15 g / m 2 The ejection amount was adjusted accordingly.

[0121] (3) Post-treatment (application of the first post-treatment liquid) Next, the post-treatment liquid 1-1 (the first post-treatment liquid) was applied onto the image of the fabric on which the above image was formed under the same conditions as the above ink, and then dried at 150°C for 3 minutes. At that time, the adhesion amount of the post-treatment liquid 1-1 was 15 g / m 2 The adhesion amount of the post-treatment liquid 1-1 was adjusted by voltage.

[0122] (4) Post-treatment (application of the second post-treatment liquid) Furthermore, the post-treatment liquid 2-1 (the second post-treatment liquid) was applied onto the image of the printed fabric under the same conditions as the above ink to print a 100% solid image, and then dried at 150°C for 3 minutes. At that time, the ejection amount of the post-treatment liquid 2-1 was adjusted by adjusting the ejection voltage.

[0123] <Tests 2 to 16 and 22> An image formation was obtained in the same manner as in Test 1, except that the combination of the first post-treatment liquid and the second post-treatment liquid was changed as shown in Table 3.

[0124] <Tests 17 to 21> An image formation was obtained in the same manner as in Test 1, except that the first post-treatment liquid was changed as shown in Table 3 and the second post-treatment liquid was not used.

[0125] <Evaluation> The texture and wet rubbing fastness of the obtained image formation were evaluated by the following methods. Furthermore, the yellowing of the white background and the water swelling degree when using the combination of the first post-treatment liquid and the second post-treatment liquid shown in Table 3 were also evaluated.

[0126] (Texture) Regarding the obtained image formation, using the bending stress B value calculated using a pure bending tester (KES-FB2-A) manufactured by Kato Tech as an index, it was evaluated according to the following criteria. 5: The B value is less than 1.5 times that before the post-treatment, and the change in texture is not noticeable even in the sensory evaluation. 4: The B value is less than 1.5 times that before the post-treatment, and the change in texture is slightly noticeable in the sensory evaluation but is not a problem. 3: The B value is 1.5 times or more and less than 2 times that before the post-treatment, and the change in texture is slightly noticeable in the sensory evaluation but is not a problem. 2: The B value is 2 times or more and less than 3 times that before the post-treatment, and there is a problem with the texture even in the sensory evaluation. 1: The B value is 3 times or more that before the post-treatment, and there is a problem with the texture even in the sensory evaluation.

[0127] (Wet rubbing fastness) The wet rubbing fastness of the obtained image formation was evaluated using a clock meter (friction tester type I) in accordance with JIS L 0849. Specifically, the image on the surface of the image formation was captured with a scanner, processed by image processing, and the contamination level of the white cloth was digitized and evaluated according to the following criteria. 5: The contamination of the white cloth is improved by 90% or more compared to the case without post-treatment. 4: The contamination of the white cloth is improved by 60% or more and less than 90% compared to the case without post-treatment. 3: The contamination of the white cloth is improved by 30% or more and less than 60% compared to the case without post-treatment. 2: The contamination of the white cloth is improved by 10% or more and less than 30% compared to the case without post-treatment. 1: The contamination of the white cloth is improved by less than 10% compared to the case without post-treatment.

[0128] (Yellowing of the white background) Onto the untreated fabric, the first post-treatment liquid shown in Table 3 was applied using the above-mentioned simple printing tester so that the application amount was 15 g / m 2 and then dried at 110 °C for 30 seconds. Next, the second post-treatment liquid shown in Table 3 was further applied using the above-mentioned simple printing tester so that the application amount was 15 g / m 2 . Then, the obtained fabric was hot-pressed at 200 °C for 15 seconds. And the degree of yellowing of the white background was visually evaluated and evaluated according to the following criteria. 5: No yellowing occurs 4: Almost no yellowing, at a non-problematic level 3: Slightly yellowing partially, at a non-problematic level 2: Slightly yellowing, at a problematic level in practical use 1: Yellowing exists, at a problematic level in practical use

[0129] (Degree of water swelling of the water-swellable resin (A) after treatment with the second post-treatment liquid) 1) An aqueous dispersion of the water-swellable resin (A) which is a raw material of the first post-treatment liquid was dried and solidified at 70 °C and 30 - 35 RH% for 48 hours to obtain pellet 1 (before treatment). 2) Pellet 1 was immersed in the second post-treatment liquid diluted so that the mass ratio with the water swelling inhibitor (B) was the same as y / x in Table 3 for 5 minutes, and then dried and solidified under the same conditions as above to obtain pellet 2 (after treatment). 3) For each of the obtained pellets 1 and 2, after immersing in ion-exchanged water at 20 °C for 5 minutes, they were dried under the same conditions as above and the weight was measured. And for each of pellets 1 and 2, the weight before and after immersion in ion-exchanged water was applied to the following formula to calculate the degree of water swelling (%). Formula (1): Degree of water swelling (%) = (weight of pellet after immersion - weight of pellet before immersion) / (weight of pellet before immersion) × 100 The degree of water swelling of pellet 1 corresponds to the degree of water swelling of the water-swellable resin (A) (before treatment with the second post-treatment liquid); the degree of water swelling of pellet 2 corresponds to the degree of water swelling of the water-swellable resin (A) (after treatment with the second post-treatment liquid).

[0130] The evaluation results of Tests 1 to 22 are shown in Table 3. Regarding the image-formed product of Test 11, upon cross-sectional observation, it was confirmed that the thickness of the first treatment layer was 3.5 μm and the thickness of the second treatment layer was about 1 μm.

[0131]

Table 3

[0132] As shown in Table 3, the image-formed products (the present invention) of Tests 1 to 16 using both the predetermined first post-treatment liquid and the second post-treatment liquid all have good wet rubbing fastness without impairing the texture, and it can be seen that the yellowing of the white background is also small.

[0133] On the other hand, it can be seen that Tests 17 to 21 that did not use the second post-treatment liquid all have low wet rubbing fastness. Further, in Test 22, since the nonionic urethane resin contained in Treatment Liquid 1-4 does not react or interact with the anionic urethane resin contained in Treatment Liquid 2-6, it can be seen that the obtained image-formed product not only has poor texture but also has low wet rubbing fastness.

[0134] According to the present invention, it is possible to provide an image forming method capable of imparting an image-formed product having sufficient water resistance (wet rubbing fastness) without impairing the texture of the fabric.

Claims

1. A step of applying a treatment liquid containing 2% by mass or more of a water-swellable resin (A) and water onto a fabric on which a coloring material layer is formed, or applying a treatment liquid containing a coloring material, 2% by mass or more of a water-swellable resin (A), and water onto the fabric to form a coating film, A step of applying a post-treatment liquid containing a water-swell prevention agent (B) and water onto the surface of the coating film, comprising On the surface of the coating film, the water-swell prevention agent (B) reacts or interacts with the water-swellable resin (A) to reduce the water-swell degree of the water-swellable resin (A). An image forming method.

2. The coloring material layer contains a pigment. The image forming method according to Claim 1.

3. The water-swellable resin (A) is a resin having a water-swell degree of 70% or more represented by the following formula (1). The image forming method according to Claim 1 or 2. Formula (1): Water-swell degree (%) = (weight of pellet after immersion - weight of pellet before immersion) / (weight of pellet before immersion) × 100 (In formula (1), The weight of the pellet before immersion indicates the weight of the pellet of the water-swellable resin (A) before immersion in ion-exchanged water at 20°C. The weight of the pellet after immersion indicates the weight of the pellet of the water-swellable resin (A) after immersion in ion-exchanged water at 20°C for 5 minutes.)

4. The water-swellable resin (A) has an ionic group. The water-swell prevention agent (B) has an ionic group that pairs with the ionic group. The image forming method according to any one of Claims 1 to 3.

5. The water-swellable resin (A) has an anionic group. The water-swell prevention agent (B) has a cationic group. The image forming method according to Claim 4.

6. The water-swellable resin (A) is a (meth)acrylic resin having an anionic group. The image forming method according to Claim 5.

7. The water-swell prevention agent (B) is one or more selected from the group consisting of a (meth)acrylic resin having a cationic group, a polyvalent metal salt, and an organic acid. The image forming method according to Claim 5 or 6.

8. The mass ratio y / x of the adhesion amount x of the water-swellable resin (A) to the adhesion amount y of the water-swell prevention agent (B) is 0.01 or more and less than 1. The image forming method according to any one of Claims 1 to 7.

9. A treatment liquid set used for inkjet printing, A first post-treatment liquid containing 2% by mass or more of a water-swellable resin (A) and water, A second post-treatment liquid containing a water swelling inhibitor (B) that reacts or interacts with the water swelling resin (A) to reduce the water swelling degree of the water swelling resin (A), and water comprising a treatment liquid set.

10. The water swelling resin (A) is a resin having a water swelling degree of 70% or more represented by the following formula (1). The treatment liquid set according to claim 9. Formula (1): Water swelling degree (%) = (weight of pellets after immersion - weight of pellets before immersion) / (weight of pellets before immersion) × 100 (In formula (1), the weight of the pellets before immersion indicates the weight of the pellets of the water swelling resin (A) before immersion in ion-exchanged water at 20°C, and the weight of the pellets after immersion indicates the weight of the pellets of the water swelling resin (A) after immersion in ion-exchanged water at 20°C for 5 minutes.)

11. The water swelling resin (A) has an ionic group, and the water swelling inhibitor (B) has an ionic group that pairs with the ionic group. The treatment liquid set according to claim 9 or 10.

12. The water swelling resin (A) has an anionic group, and the water swelling inhibitor (B) has a cationic group. The treatment liquid set according to claim 11.

13. The water swelling resin (A) is a (meth)acrylic resin having an anionic group. The treatment liquid set according to claim 12.

14. The water swelling inhibitor (B) is one or more selected from the group consisting of a (meth)acrylic resin having a cationic group, a polyvalent metal salt, and an organic acid. The treatment liquid set according to claim 12 or 13.

Images