WO2025143895A1 - Basic ink composition for digital printing and printing method using same - Google Patents

Abstract

The present invention relates to a composition for printing, the composition comprising a binder, a solvent, and a reaction controller. When the composition of the present invention is used, ink composition components may be easily coagulated on the surface of an object, and the obtainable object image quality or abrasion resistance may be further enhanced.

Description

Basic ink composition for digital printing and printing method using the same

The present invention relates to an ink composition for digital printing and a printing method using the same.

In order to print high-quality color images, inkjet printing is performed in small batches of various contents on various types and shapes of substrates, such as fabric surfaces. Inkjet printing is a broad technology that records characters and patterns on a printing surface by ejecting a stream of a specific liquid ink composition as tiny droplets from a cluster of fine nozzles (printheads) in response to an electrical signal generated by a microprocessor. A typical inkjet printing system records characters, symbols, and patterns by converting an electrical signal into a mechanical signal for continuous or on-demand ejection of an ink composition continuously supplied and stored in a nozzle head section.

Ink compositions suitable for inkjet printing include aqueous ink compositions and non-aqueous solvent-based ink compositions. A more commonly used inkjet composition is an aqueous ink composition, which generally contains water and a colorant, typically a dye or pigment dispersion, and may further contain a number of additives for imparting specific properties to the applied ink (see published JP 2009-215506 A). At this time, depending on the composition of the ink composition used or the type of the pretreatment solution or the posttreatment solution, the quality of the final printed matter can be determined. In order to obtain such high-quality printed matter, the present inventors have invented a printing composition.

The present invention aims to provide a basic ink composition for digital printing, which comprises a binder; a solvent; and a reaction regulator. In addition, the present invention aims to provide a digital printing method, which comprises a step of spraying the composition onto a target object; and a step of drying the output. In addition, the present invention aims to provide an object on which the composition is printed. In addition, the present invention aims to provide a method for producing a basic ink composition for digital printing by mixing a binder; a solvent; and a reaction regulator.

A basic ink composition for digital printing comprising a binder; a solvent; and a reaction regulator for achieving the above-described purpose, wherein the pH of the composition is 7 to 9, is provided.

The solvent may be one or more of dihydric glycols—ethylene glycol, glycerol, diethylene glycol, propylene glycol, acetone, and dichloromethane.

The binder may be a block isocyanate or an acrylic-urethane polymer.

The reaction moderator may be one or more of sodium lactate aqueous solution, acetic acid, and butyl acetate.

The reaction moderator may have a mass ratio of sodium lactate aqueous solution and acetic acid of 10:1 to 15:1.

The acrylic-urethane polymer can have a ratio of acrylic to urethane of 0.5:9.5 to 1.5:8.5.

The Tg of the acrylic-urethane polymer can be between -50 degrees and -40 degrees.

It may additionally contain one or more of a surfactant, a corrosion inhibitor, and an antioxidant.

In one specific embodiment of the present invention, a digital printing method is provided, including the step of spraying the composition onto a target object; and the step of drying the output. In the specific embodiment, the digital printing method provides that the target object is any one selected from the group consisting of natural fibers, synthetic fibers, and semi-synthetic fibers, such as silk, cotton, wool, nylon, polyester, and rayon.

In one specific embodiment of the present invention, the composition provides a printed object.

In one specific embodiment of the present invention, a method for producing a basic ink composition for digital printing by mixing a binder; a solvent; and a reaction regulator, wherein a pH regulator is added so that the pH of the ink composition becomes pH 7 to 9.

The binder may be a block isocyanate or an acrylic-urethane polymer.

The reaction moderator may be at least one of an aqueous sodium lactate solution, acetic acid, and butyl acetate.

The reaction moderator may have a mass ratio of sodium lactate aqueous solution and acetic acid of 10:1 to 15:1.

In one specific embodiment of the present invention, the binder is an important component of the ink, which serves to fix the pigment or colorant to the printing material. The binder is a substance that strengthens the adhesion between the printed material and the pigment when the pretreatment liquid or ink is dried after printing. This has a significant effect on the durability and quality of the final printed material. The main functions of the binder are to strengthen the adhesion (so that the ink adheres well to the printed material), which is especially important on smooth or non-absorbent surfaces, to protect the color (so that the pigment is evenly distributed on the printed material), to provide vivid and uniform colors, to improve durability (after drying, the binder increases the resistance of the printed material to abrasion, discoloration, and chemical damage), and to provide flexibility (some binders impart flexibility to the printed material, thereby increasing its resistance to bending or other physical stresses). The type of binder is determined according to the type of material being printed, the use of the printed material, and the required durability and quality standards for a specific purpose. Although not limited thereto, for example, for binders for digital printing pretreatment, block isocyanates or acrylic-urethane polymers may be used.

In one specific embodiment of the present invention, the reaction regulator is for controlling the physicochemical properties of the ink composition during the process of being attached to the target object, and controlling the physicochemical reaction with the ink composition after being attached to the target object. This changes the reaction environment or reaction conditions including pH, and for example, but not limited to, includes at least one of calcium chloride dihydrate, calcium nitrate tetrahydrate, calcium magnesium dihydrate, magnesium chloride, acetic acid, lactic acid, tartaric acid, sodium lactate aqueous solution, acetic acid, and butyl acetate.

In one specific example of the present invention, the pH regulator is an agent that regulates the pH of the reaction solution,

But are not limited to, triethylamine (TEA), DEA, disodium phosphate and aminomethyl propanediol can be used, and any one or more of ethylamine, propylamine, butylamine, diethylamine, dipropylamine, dibutylamine, triethylamine, tributylamine, monoethanolamine, diethanolamine, triethanolamine, 2-dimethylamino-2-methyl-1-propanol, 1-amino-2-propanol, 1-dimethylamino-2-propanol, 3-dimethylamino-1-propanol, 2-amino-1-propanol, 2-dimethylamino-1-propanol, 2-diethylamino-1-propanol, 2-diethylamino-1-ethanol, 2-ethylamino-1-ethanol, 1-(dimethylamino)2-propanol, N-methyldiethanolamine, N-propyldiethanolamine, Any one or more of N-isopropyldiethanolamine, N-(2-methylpropyl)diethanolamine, N-n-butyldiethanolamine, N-t-butylethanolamine, N-cyclohexyldiethanolamine, 2-(dimethylamino)ethanol, 2-diethylaminoethanol, 2-dipropylaminoethanol, 2-butylaminoethanol, 2-t-butylaminoethanol, 2-cycloaminoethanol, 2-amino-2-pentanol, 2-[bis(2-hydroxyethyl)amino]-2-methyl-1-propanol, 2-[bis(2-hydroxyethyl)amino]-2-propanol, N,N-bis(2-hydroxypropyl)ethanolamine, 2-amino-2-methyl-1-propanol, tris(hydroxymethyl)aminomethane, and triisopropanolamine can be used.

In one specific example of the present invention, the composition for pretreatment of printing is. By treating a pretreatment liquid before attaching the ink composition, the components of the ink composition can be easily aggregated on the surface of the object, and the image quality or friction durability of the object that can be obtained can be further improved.

In one embodiment of the present invention, the acrylic-urethane polymer is a mixture of two different types of polymers, acrylic and urethane, which combine the unique properties of each polymer to create the properties of a new material. Although not limited thereto, the acrylic polymer provides excellent weather resistance, color stability, transparency and gloss, is resistant to UV rays, does not fade, and leaves a beautiful gloss on the surface. Therefore, acrylic can be widely used in paints, coatings, adhesives, inks, and various plastic products. The urethane polymer has high flexibility, wear resistance, and chemical resistance, so it has excellent shock absorption and a wide range of elasticity depending on the usage environment, and is used in various applications such as flooring, shoes, sealants, adhesives, and even automobile parts. In other words, the acrylic-urethane polymer mixture combines the advantages of these two polymers to create durable coatings, adhesives, sealants, etc., and the physical and chemical properties change depending on the mixing ratio. Depending on the intended purpose, a composition for printing is provided having a ratio of acrylic to urethane of 05:95 to 15:85.

In one embodiment of the present invention, the glass transition temperature (Tg) refers to the temperature at which a polymer material changes from a hard and brittle 'glassy state' to a soft and rubbery 'rubber state'. At this temperature, the physical properties of the polymer material change dramatically. The glass transition temperature is an important concept in understanding the thermal properties of a material. Below this temperature, the polymer material behaves hard and brittle like glass, and above the glass transition temperature, the material becomes more flexible and elastic, and can absorb more energy. For example, the glass transition temperature is an important consideration when determining the usable temperature range of a polymer material such as a plastic, rubber, or adhesive. If the temperature of the environment in which the material will be used is lower than the glass transition temperature, the material hardens, and if the temperature is higher than the glass transition temperature, the material softens. In particular, the glass transition temperature of a polymer is determined by several factors such as its structure, molecular weight, degree of crosslinking, and presence of additives. These characteristics play an important role in the design and application of the material. In particular, in compositions for printing pretreatment, the Tg of the acrylic-urethane polymer is, but is not limited to, in the range of -50 degrees to -40 degrees.

In one specific example of the present invention, the object refers to various printing objects, including but not limited to, any one selected from the group consisting of natural fibers, synthetic fibers and semi-synthetic fibers, such as silk, cotton, wool, nylon, polyester and rayon.

In one embodiment of the present invention, the drying process is a process for drying a pretreatment composition or ink composition attached to a target object. The drying temperature is not particularly limited, but is, for example, 60 to 150°C; 100 to 150°C or 130 to 150°C. In addition, the drying time is not particularly limited, but may be, for example, 30 seconds to 5 minutes. At such a temperature, damage to the target object can be suppressed to a low level, so that printing can be very suitably performed on a target object containing any one selected from the group consisting of nylon fibers and polyester fibers. In addition, the drying process is all used after the ink attachment process, the pretreatment liquid attachment process or the posttreatment liquid attachment process. The method for attaching the pretreatment composition or the ink composition can be any one of an inkjet method, a bar coater, a roll coater and a spray method.

In one embodiment of the present invention, a digital printing method is a technology for printing a digital-based image directly from a computer or digital storage medium onto the surface of various materials, and this method outputs an image without a film or printing plate, unlike traditional printing techniques. It is efficient for small-scale printing or personalized printing. Digital printing uses an inkjet or laser printer and can print data immediately, providing fast production speed and high flexibility. Application examples include personalized marketing material printing (printing marketing materials including personal information such as each recipient's name or address in batches); on-demand printing (printing only as many books or documents as needed, reducing inventory burden compared to mass printing); high-resolution image printing (digital printers directly print high-resolution images on various materials such as paper and canvas); variable data printing (VDP) (different images or texts can be inserted into each printed material, enabling personalized printing); and large-format printing (printing large banners, posters, signboards, etc. in high definition).

In one embodiment of the present invention, the solvent is not particularly limited, and examples thereof include glycols, glycol monoethers, glycol diethers, glycol monoesters, glycol diesters, nitrogen-containing solvents, monohydric alcohols, and polyhydric alcohols such as glycerin. Examples of the glycols are not particularly limited, and examples thereof include ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, 1,3-propanediol, 1,2-butanediol, 1,2-pentanediol, 2-methylpentane 1,3-diol, 2-methylpentane 1,4-diol, 1,2-hexanediol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, and the like. Examples of glycol monoethers include, but are not particularly limited to, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, diethylene glycol monomethyl ether, ethylene glycol monobutyl ether, diethylene glycol monoethyl ether, diethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, dipropylene glycol monomethyl ether, dipropylene glycol monoethyl ether, triethylene glycol monomethyl ether, and the like. Examples of glycol diethers include, but are not particularly limited to, ethylene glycol dimethyl ether, ethylene glycol diethyl ether, ethylene glycol dibutyl ether, ethylene glycol methyl ether, ethylene glycol ethyl ether, and the like. Examples of glycol monoesters include, but are not particularly limited to, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, diethylene glycol monomethyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, propylene glycol monomethyl ether acetate, dipropylene glycol monomethyl ether acetate, and methoxybutyl acetate. As the glycol esters, there may be mentioned, but are not particularly limited, examples thereof include ethylene glycol diacetate, ethylene glycol acetate, propylene glycol diacetate, dipropylene glycol diacetate, ethylene glycol acetate propionate, ethylene glycol acetate butyrate, ethylene glycol acetate butyrate, ethylene glycol acetate propionate, ethylene glycol acetate butyrate, propylene glycol acetate propionester, propylene glycol acetate butyrate, dipropylene glycol acetate butyrate, dipropylene glycol acetate propion ester, and the like. As the nitrogen solvent, there may be mentioned, but are not particularly limited, examples thereof include 2-pyrrolidone, N-methyl-2-pyrrolidone, N-ethyl-2-pyrrolidone, and the like.

Examples of the monohydric alcohol include, but are not particularly limited to, alcohols such as methanol, ethanol, n-propyl alcohol, iso-propyl alcohol, n-butanol, 2-butanol, tert-butanol, iso-butanol, n-pentanol, 2-pentanol, 3-pentanol, and tert-pentanol. The total content of the organic solvent is 50 to 30 mass%, 75 to 275 mass%, or 15 to 25 mass% with respect to the total amount of the ink composition. When the total content of the organic solvent is within the above range, in addition to the friction durability and storage stability, the peeling resistance of the printed surface and the feel of the target tend to be further improved. In particular, the pretreatment solvent is, but is not limited to, at least one of divalent glycols - ethylene glycol, glycerol, diethylene glycol, propylene glycol, acetone and dichloromethane.

In one specific example of the present invention, the resin particles are not particularly limited, and examples thereof include acrylic resin particles, urethane resin particles, polyester resin particles, and polyethylene resin particles. Among these, urethane resin particles can be used. By using such resin particles, in addition to friction durability and storage stability, the peeling resistance of the printed surface and the feel of the target tend to be further improved. The resin particles may be used singly, or two or more types may be used in combination. The acrylic resin particles are not particularly limited, and examples thereof include those obtained by polymerizing (meth)acrylic monomers such as (meth)acrylic acid and (meth)acrylic acid esters, and those obtained by copolymerizing (meth)acrylic monomers with other monomers. Among these, anionic acrylic resin particles can be used.

As the urethane resin particle, there is no particular limitation as long as it is a resin particle having a urethane bond in the molecule, and examples thereof include a polyether type urethane resin including an ether bond in the main chain, a polyester type urethane resin including an ester bond in the main chain, and a polycarbonate-containing film urethane resin including a carbonate bond in the main chain. Among these, a polyether type urethane resin or a polycarbonate-containing film urethane resin can be used, and a polycarbonate-containing film urethane resin can be used. In addition, from the viewpoint of improving dispersion stability, etc., anionic urethane resin particles having a carboxyl group, a sulfo group, a hydroxyl group, or the like can be used. The polyester resin particle is not particularly limited as long as it can be obtained by a reaction between an acid component and an arcor component. Examples of phosphate components include terephthalic acid, isophthalic acid, naphthalene dicarboxylic acid, biphenyl dicarboxylic acid, oxalic acid, succinic acid, adipic acid, sebacic acid, dodecanedioic acid, fumaric acid, maleic acid, itaconic acid, cyclohexanedicarboxylic acid, and tetrahydrophthalic acid.

In addition, as the arcor component, glycols, etc., exemplified as organic solvents, can be exemplified. In addition, as the resin particles, there are no particular limitations, and examples thereof include non-crosslinkable resin particles and crosslinkable resin particles having a crosslinkable group. Among these, non-crosslinkable resin particles can be used. The crosslinkable group may be one that forms a crosslinked structure by reacting with a crosslinkable group, or may be one that forms a crosslinked structure by reacting with a functional group different from the crosslinkable group. By using non-crosslinkable urethane resin particles, the preservation stability and the feel of the obtainable object tend to be further improved. The content of the resin particles is 2.0 to 15 mass%, 3.0 to 10 mass%, or 5.0 to 8.0 mass% with respect to the total amount of the ink composition. When the content of the resin particles is 2.0 mass% or more, the dry friction durability of the obtainable object tends to be further improved. In addition, since the content of resin particles is 10 mass% or less, the obtainable object feel, friction durability, and preservation stability of the ink composition tend to be further improved.

In one specific example of the present invention, a colorant may be additionally included in the ink composition. The colorant may utilize at least one of a pigment and a dye. Among these, the ink composition of the present embodiment may be a pigment dyeing ink including a pigment. Since the problem of friction durability is particularly likely to occur in the case of pigment dyeing, it is useful as a composition. In addition, when the colorant is a pigment, it is possible to print on various objects such as cotton, polyester, and nylon. As the pigment, there are no particular limitations, but examples thereof include carbon black (C.I. Pigment Black 7) types such as no black, lamp black, acetylene black, and channel black; inorganic pigments such as iron oxide and titanium oxide; quinacridone pigments;

Examples of organic pigments include quinacridonequinone pigments, dioxazine pigments, phthalocyanine pigments, anthrapyrimidine pigments, anthanthrone pigments, indanthrone pigments, furavanthrone pigments, perylene pigments, diketopyrrolopyrrole pigments, perinone pigments, quinophthalone pigments, anthraquinone pigments, thioindigo pigments, benzimidazoron pigments, isoindolinone pigments, azomethine pigments, and azo pigments. As the dye, there are no particular limitations, but examples thereof include acid dyes such as C.I. Acid Yellow, C.I. Acid Red, C.I. Acid Blue, C.I. Acid Orange, C.I. Acid Violet, and C.I. Acid Black; basic dyes such as C.I. Basic Yellow, C.I. Basic Red, C.I. Basic Blue, C.I. Basic Orange, C.I. Basic Violet, and C.I. Basic Black; C.I. Direct Yellow, C.I. Deluxe Red, C.I. Deluxe Blue, C.I. Direct Orange, C.I. Da

Direct dyes such as Elect Violet, C.I. Direct Black; reactive dyes such as C.I. Reactive Yellow, C.I. Reactive Red, C.I. Reactive Blue, C.I. Reactive Orange, C.I. Reactive Violet, C.I. Reactive Black; disperse dyes such as C.I. Disperse Yellow, C.I. Disperse Thread, C.I. Disperse Blue, C.I. Disperse Orange, C.I. Disperse Violet, C.I. Disperse Black. The dyes may be used singly, or two or more may be used in combination. The content of the coloring material is 1.0 to 10 mass%, or 2.5 to 7.5 mass%, based on the total amount of the ink composition.

In one specific embodiment of the present invention, a surfactant may be additionally included in the composition. As the surfactant, there may be mentioned, but is not particularly limited, examples thereof, acetylene glycol-based surfactants, fluorine-based surfactants, and silicone-based surfactants. As the acetylene glycol-based surfactant, there may be mentioned, but is not particularly limited, examples thereof include, but are not limited to, alkylene oxide adducts of 2,4,7,9-tetramethyl-5-crepe de syn-4,7-diol and 2,4,7,9-tetramethyl-5-crepe de syn-4,7-diol, and alkylene oxide adducts of 2,4-dimethyl-5-crepe de syn-4-ol and 2,4-dimethyl-5-crepe de syn-4-ol, and at least one selected from the group consisting of: As the fluorine-based surfactant, there are no particular limitations, and examples thereof include perfluoroalkyl sulfonates, perfluoroalkyl carboxylates, perfluoroalkyl phosphate esters, perfluoroalkyl ethylene oxide adducts, perfluoroalkyl betaines, and perfluoroalkyl amine oxide compounds. As the silicone-based surfactant, there are polysiloxane-based compounds, polyether-modified organosiloxanes, and the like. The content of the surfactant is 0.1 to 1.0 mass% or 0.1 to 0.5 mass% with respect to the total amount of the ink composition. As the polyurethane resin, there are no particular limitations, as long as it is a resin having a urethane bond in its molecule, and examples thereof include a polyether-type urethane resin including an ether bond in the main chain, a polyester-type urethane resin including an ester bond in the main chain, and a polycarbonate-containing film urethane resin including a carbonate bond in the main chain. As the polyester resin, there are no particular limitations, but examples thereof include those obtained by the reaction of an acid component and an arcor component. As for the acid component and the arcor component, the same materials as those described above can be used. As the acrylic resin, any resin polymerized from a monomer containing at least acrylate or acrylic acid is sufficient, and may also contain other monomers such as styrene. The content of the resin is 1.0 to 10 mass%, 1.5 to 10 mass%, or 2.5 to 7.5 mass% with respect to the total amount of the post-treatment solution.

In one specific example of the present invention, an inkjet head used in an inkjet method is a head that ejects an ink composition toward a target object and performs output, and the head has a cavity that ejects the ink composition from a nozzle, a ejection driving unit that provides a driving force for ejection to the ink composition, and a nozzle that ejects the ink composition outside the head. The ejection driving unit can be formed using an electromechanical conversion element such as a piezoelectric element that changes the volume of the cavity according to mechanical deformation, or an electronic thermal conversion element that generates heat to generate bubbles in ink and ejects them.

Various embodiments of the present invention are described with reference to the drawings. In the following description, numerous specific details are set forth, such as specific configurations, compositions, and processes, in order to provide a thorough understanding of the present invention. However, certain embodiments may be practiced without one or more of these specific details, or in conjunction with other known methods and configurations. In other instances, well-known processes and manufacturing techniques are not described in specific detail so as not to obscure or overshadow the present invention. Reference throughout this specification to an embodiment is intended to imply that a particular feature, configuration, composition, or characteristic described in connection with the embodiment is included in one or more embodiments of the present invention. Thus, the appearance of an embodiment in various places throughout this specification is not necessarily representative of the same embodiment of the present invention. Additionally, the particular features, configurations, compositions, or characteristics may be combined in any suitable manner in one or more embodiments.

When the composition of the present invention is used, the components of the ink composition become more likely to aggregate on the surface of the object, and the image quality and friction durability of the object that can be obtained can be further improved.

In addition, by implementing the pH of the composition to be 7 to 9, corrosion due to oxidation of the device (e.g., print head, etc.) in which the composition is used may not occur.

Figure 1 illustrates the preprocessing actions and processes.

Hereinafter, the present invention will be described in more detail through examples. These examples are only intended to explain the present invention more specifically, and it will be apparent to those skilled in the art that the scope of the present invention is not limited by these examples according to the gist of the present invention.

While the specific parts of the present invention have been described in detail above, it is obvious to those skilled in the art that such specific description is merely an example of implementation and that the scope of the present invention is not limited thereto. Accordingly, the actual scope of the present invention will be defined by the appended claims and their equivalents.

1. Preparation of pretreatment agent and ink composition

1.1. Pretreatment solution

The pretreatment solution was prepared as shown in the table below:

Composition and weight ratio of pretreatment agent ingredient Manufacturing example reaction
Regulator Magnesium chloride 1 Acetic acid 4 Lactic acid/sodium lactate 5 Anthracite acid 10 Total weight 20 menstruum Propylene glycol 10 Dichloromethane 30 Pigment Carbon black 15 bookbinder Acrylic-urethane polymer resin 5 Additives Surfactant, anti-corrosion agent, anti-oxidant 20 Total weight (%) 100

Each component was placed in a mixing tank to obtain the composition described in Table 1 above, stirred and mixed, and then filtered through a membrane filter of 5 to 10 μm to obtain a pretreatment solution for each manufacturing example. The numerical values of each component shown in each example in Table 1 above represent mass (w/w)% unless otherwise specified. 1.2. Ink Composition

Composition and weight ratio of ink composition ingredient Manufacturing example 1 Manufacturing example 2 Manufacturing example 3 Manufacturing example 4 Manufacturing example 5 Manufacturing example 6 reaction
Regulator Sodium lactate solution 7 10 15 5 12 14 Acetic acid 7 5 5 15 3 3 Butyl acetate 6 5 0 5 5 3 Total weight 20 20 20 20 20 20 menstruum Diglycols-Ethylene Glycol 10 0 0 0 10 10 Glycerol 0 10 0 0 5 8 Diethylene glycol 0 0 10 0 15 10 Propylene glycol 0 0 0 10 10 12 Acetone 0 0 0 3 0 0 Dichloromethane 30 30 30 27 0 0 Total weight 40 40 40 40 40 40 Pigment Carbon black 15 15 15 15 15 15 bookbinder Block isocyanate 5 0 5 0 5 5 Acrylic-urethane polymer resin 0 5 0 5 10 15 Additives Surfactant, anti-corrosion agent, anti-oxidant 20 20 20 20 10 10 Total weight (%) 100 100 100 100 100 100

In order to obtain the composition described in Table 2 above, each component was placed in a mixing tank, mixed and stirred, and further filtered through a membrane filter of 5 to 10 μm to obtain an ink composition. The numerical value of each component shown in each example in Table 2 above represents mass (w/w)% unless otherwise specified. Materials commonly used in Tables 1 and 2 above are as follows:

Pigment: Carbon black (Orient Chemical Industries, Ltd., product name BONJET BLACK CW－1)

Surfactant: Orphin E1010 (Nissin Chemical Industries, Ltd., acetylene glycol surfactant)

Corrosion inhibitor: Benzotriazole (ChemWorld 506, ChemWorld)

Antioxidant: Butylated Hydroxytoluene (Lab Alley)

2. Preparation of pretreatment agent and ink composition

2.1. Attachment and drying of pretreatment solution

Pretreatment liquid attachment is a process of attaching the pretreatment liquid to the target object, and the attachment area of the pretreatment liquid and the attachment area of the ink composition are made to overlap each other. That is, after applying to the target object so that the pickup rate is 80%, it is heated at 100°C for 3 minutes, and then the next ink attachment process is performed.

2.2. Attachment and drying of ink composition

The ink attachment process involved spraying the ink composition manufactured in Example 1 through an inkjet head using an inkjet printer PM-870 C (manufactured by Seiko Epson Co., Ltd.) to fix it to an object, and drying it in the same manner as the pretreatment liquid drying method of 2.1.

3. Evaluation of pretreatment agent and ink composition

3.1. Preservation stability

The printed matter manufactured through the above Examples 1 and 2 was put into a sample bottle, sealed, and then the glass bottle was placed in a thermostatic bath at 40°C and stored for 2 weeks. Using a vibrating viscometer, the viscosity before and after storage was measured in accordance with JIS Z8809, and the viscosity change rate after leaving for 2 weeks was calculated, and the storage stability was evaluated according to the evaluation criteria below. If the evaluation of the storage stability is A or B, it can be said that good results are obtained.

A: Viscosity change rate is 3% or less

B: Viscosity change rate is between 3% and 5%

C: Viscosity change rate exceeds 5%

3.2. Abrasion resistance

The ink composition of Example 1 was filled into a cartridge of an inkjet printer PM-870 C (manufactured by Seiko Epson Co., Ltd.). After filling, a nozzle check pattern was printed to confirm that there was no filling defect or nozzle loading. For a target object (polyester (PES) or nylon 100%, plain weave) to which the pretreatment liquid of Example 1 was applied, the ejected ink weight per dot was set to about 40 ng, and the ink adhesion density in the longitudinal and transverse directions was printed at 360 × 360 dpi. In addition, the pretreatment liquid was applied to the target object so that the pickup rate was 80%, and then attached by heating at 100°C for 3 minutes. Thereafter, a polyester resin (Dongyangbang Co., Ltd., Bayronar MD2000)

A 5 wt% treatment solution was attached using an inkjet, and heated at 140°C for 3 minutes to obtain a printed matter. The obtained printed matter was evaluated for friction durability according to ISO-105 X12. The evaluation criteria are shown below. If the evaluation of friction durability is A to C, it can be said that good results are obtained.

A: Wet friction exceeds level 3

B: Wet friction level 3

C: Wet friction 2-3 grade

D: Wet friction level 2 or lower

3.3. Touch

For the print obtained in the above 3.2, the impression was judged by directly touching the stamped part with the palm of the hand and judging the feeling at that time according to the following criteria. The judgment was conducted by three people, and the opinion with the most support was considered the result of the judgment. In the case where the judgment was divided into one person each, the middle opinion among them was judged.

A: The stamping part is hard and the feel is almost the same as the original object.

B: The stamped part is hard, or the feel is slightly different from the original object, but there is no problem using it.

C: The hardness or texture of the stamped part is worse than that of the original object, but within an acceptable range.

D: The stamped part is hard or the feel is worse than the original object, and is in an unacceptable range.

3.4. Peeling resistance

For the printed matter obtained in the above 3.2, a load of 10 gf/cm was applied from above and left for one week. After that, the printed matter folded in half was opened and it was checked whether or not the printed surface was peeled off. Based on the results of the check, the peeling resistance was evaluated. The evaluation criteria are shown below.

A: No adhesion or peeling is recognized on the printed surface.

B: Adhesion is recognized on the printed surface, but peeling is not recognized.

C: Some peeling is observed on the printed surface.

D: Peeling is recognized on the printed surface

3.5. Environmental Adaptability

The ink composition composed of ingredients with relatively high safety for the human body was evaluated as A, and the others were evaluated as B.

4. Evaluation Results

The evaluation results are shown in the table below.

Evaluation results by ink composition combination evaluation Manufacturing example 1 Manufacturing example 2 Manufacturing example 3 Manufacturing example 4 Manufacturing example 5 Manufacturing example 6 Preservation stability A B A A A A Friction durability A A B B A A Touch B A B B A B Peelability B B A A A B Environmental adaptability B B A A A A

While the specific parts of the present invention have been described in detail above, it is obvious to those skilled in the art that such specific description is merely an example of implementation and that the scope of the present invention is not limited thereto. Accordingly, the actual scope of the present invention will be defined by the appended claims and their equivalents.

Claims (15)

A basic ink composition for digital printing comprising a binder; a solvent; and a reaction regulator, A composition having a pH of 7 to 9. In paragraph 1, A composition wherein the solvent is at least one of dihydric glycols - ethylene glycol, glycerol, diethylene glycol, propylene glycol, acetone, and dichloromethane. In paragraph 1, The binder is a composition which is a block isocyanate or acrylic-urethane polymer. In paragraph 1, The reaction regulator is a composition comprising at least one of sodium lactate aqueous solution, acetic acid, and butyl acetate. In paragraph 4, The reaction regulator is a composition having a mass ratio of sodium lactate aqueous solution and acetic acid of 10:1 to 15:1. In the third paragraph, Acrylic-urethane polymer is a composition having a ratio of acrylic to urethane of 0.5:9.5 to 1.5:8.5. In paragraph 6, A composition having an acrylic-urethane polymer Tg of -50 degrees to -40 degrees. In Article 7, A composition further comprising at least one of a surfactant, a corrosion inhibitor, and an antioxidant. A step of preparing an output by spraying the composition of Article 1 onto the target object; and Comprising a step of drying the above output; Digital printing method. In Article 9, The above object is a composition for printing on any one selected from the group consisting of natural fibers, synthetic fibers and semi-synthetic fibers, such as silk, cotton, wool, nylon, polyester and rayon. An object on which the composition of claim 1 is printed. A method for producing a basic ink composition for digital printing by mixing a binder, a solvent, and a reaction regulator, A method of adding a pH adjuster to adjust the pH of an ink composition to pH 7 to 9. In Article 12, The binder is a block isocyanate or acrylic-urethane polymer. In Article 12, A method wherein the reaction regulator is at least one of a sodium lactate aqueous solution, acetic acid, and butyl acetate. In Article 14, The reaction regulator is a method in which the mass ratio of sodium lactate aqueous solution and acetic acid is 10:1 to 15:1.

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