JPH05229246A - Processing agent for reception layer for water-base ink - Google Patents

Abstract

PURPOSE:To provide a processing agent characterized by a clear image printer with water-base ink, good absorptivity of ink, desirable adhesion to a plastic film, particularly a PET film, and excellent waterproof. CONSTITUTION:A processing agent is composed of an aqueous dispersion of a polyester resin modified by a polymer of a compound having polymerizable double bonds. The compound includes a copolymer of unsaturated carboxylic acid amide and its derivatives. The polymer is preferably used in the amount of 1-300wt.% of the polyester resin.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an aqueous ink receptive layer processing agent, and more particularly to a receptive layer processing agent for an ink jet recording sheet. The image recorded by the aqueous ink is clear and the ink absorptivity is high. The present invention relates to a processing agent having good adhesion, good adhesion to a plastic film, especially a PET film, and excellent water resistance of a film.

[0002]

2. Description of the Related Art In recent years, ink jet recording has begun to spread rapidly due to its advantages such as high speed recording, low noise, easy multicoloring and no need for development and fixing. Recording sheets used for ink jet recording include high-quality paper, continuous slip paper, art paper, coated paper, and paper having a low density without the addition of a sizing agent. JP-A-52-53012 and JP-A-52 -74340 and Japanese Patent Laid-Open No. 53-49113, ink-jet recording papers, cloths, and plastic films whose surface is made ink-absorbent with relatively good ink absorption and little ink spread , Wood boards, metal boards, etc.

The performance required for these recording sheets is that a clear image with high density can be obtained, that the ink is absorbed quickly and does not become dirty even if it is touched immediately after printing, and the spread of ink dots in the lateral direction. It is desired that the image be suppressed and a high-resolution image without bleeding be obtained. Then, conventionally, various processing agents have been proposed to solve this problem.

For example, Japanese Unexamined Patent Publication No. 52-53012 discloses an ink jet recording paper obtained by wetting a low-sized base paper with a coating material for surface processing. In addition, JP-A-5
No. 3-49113 discloses an ink jet recording paper in which a sheet containing urea-formalin resin powder is impregnated with a water-soluble polymer. Also, JP-A-55-583
No. 0 discloses an ink jet recording paper in which an ink absorbing coating layer is provided on the surface of a support, and JP-A-55-51583 discloses an example in which non-colloidal silica powder is used as a pigment in the coating layer. JP-A-55-146786 discloses an ink jet recording paper provided with a water-soluble polymer coating layer.

However, although these processing agents can provide some performance to paper such as art paper and coated paper, when the support is a plastic film such as a polyester film, the adhesive strength is insufficient, It is necessary to devise such as applying the anchor layer in advance and then applying the receiving layer. Alternatively, it may not be possible to use because an appropriate anchor coating agent cannot be found. Further, as a drawback of the conventional processing agents, when the ink absorbability is good, the water resistance is poor and it cannot be put to practical use.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to solve these drawbacks of the conventional products and to prevent ink from flowing out or bleeding at the time of ink jet recording. It is an object of the present invention to provide a processing agent capable of obtaining a receptive layer having good absorption. further,
Another important object is to provide a processing agent having sufficient adhesive force even when applied to a plastic film such as a polyester film.

[0007]

Means for Solving the Problems The inventors of the present invention have made extensive studies to solve the above problems, and as a result, achieved the present invention.
That is, the processing agent of the present invention is a polyester resin aqueous dispersion modified with a polymer of a compound having a polymerizable double bond, and the polymer is selected from unsaturated carboxylic acid amides and / or derivatives thereof. It is a processing agent for a receptive layer of an aqueous ink, which is characterized by copolymerizing one or more of the above.

As the compound having a polymerizable double bond used in the present invention, vinyl ester, unsaturated carboxylic acid ester, unsaturated carboxylic acid amide and derivatives thereof, unsaturated nitrile, unsaturated carboxylic acid, allyl compound, nitrogen-containing compound , Hydrocarbons or vinylsilane compounds are used. As the vinyl ester, vinyl propionate, vinyl stearate, higher tertiary vinyl ester, vinyl chloride or vinyl bromide is used. As the unsaturated carboxylic acid ester, methyl acrylate, ethyl acrylate, butyl acrylate, 2-ethylhexyl acrylate, methyl methacrylate, butyl methacrylate, butyl maleate, octyl maleate, butyl fumarate, octyl fumarate,
Glycidyl acrylate, glycidyl methacrylate, hydroxyethyl methacrylate, hydroxyethyl acrylate, hydroxypropyl methacrylate, hydroxypropyl acrylate, dimethylaminoethyl methacrylate,
Dimethylaminoethyl acrylate, ethylene glycol dimethacrylate, ethylene glycol diacrylate, polyethylene glycol dimethacrylate, polyethylene glycol diacrylate are used. As unsaturated carboxylic acid amides and their derivatives, acrylamide, methacrylamide, methylolacrylamide, butoxymethylolacrylamide,
N, N-dimethyl acrylamide, N, N-dimethyl methacrylamide, etc. are used. Acrylonitrile is used as the unsaturated nitrile. As the unsaturated carboxylic acid, acrylic acid, methacrylic acid, maleic acid, fumaric acid, itaconic acid, maleic acid acid ester, fumaric acid acid ester, and itaconic acid acid ester are used. As the allyl compound, allyl acetate, allyl glycidyl ether, allyl methacrylate, allyl acrylate, diallyl itaconate are used. Vinyl pyridine and vinyl imidazole are used as the nitrogen-containing compound, and ethylene, propylene, hexene, octene, styrene, vinyl toluene and butadiene are used as the hydrocarbon. As the vinylsilane compound, dimethylvinylmethoxysilane, dimethylvinylethoxysilane, methylvinyldimethoxysilane, methylvinyldiethoxysilane, γ-methacryloxypropyltrimethoxysilane, and γ-methacryloxypropylmethyldimethoxysilane are used.

The water-dispersible polyester resin used in the present invention contains a hydrophilic component such as polyethylene glycol, carboxyl group, carbonyl group, carboxylate salt, sulfonate salt, sulfate ester salt and phosphate ester salt in the molecule. Is a polyester resin which is synthesized by a known method. The polymer of the compound having a polymerizable double bond is 1 to 300% by weight with respect to the polyester, preferably 5
~ 150 wt% is used. When the unsaturated carboxylic acid amide and / or its derivative is combined in a compound having a polymerizable double bond in an amount of 10 to 100% by weight, the image sharpness, ink absorbency, and water resistance are balanced in terms of performance. Good results can be obtained.

[0010] modified method of the polyester resin with a compound having a polymerizable double bond, a radical polymerization initiator is added to the aqueous dispersion of polyester resin, 45 to 85 ⁰ C temperatures, preferably 70 to 85 ⁰ C, vinyl Add the monomer and proceed the reaction. Incidentally, potassium persulfate as a polymerization initiator,
When ammonium persulfate and azobisisobutyronitrile are used, the polyester resin is not easily modified, and a homopolymer of a vinyl compound is produced, so that the reaction with an organic peroxide is preferable. Also in the use of emulsifiers, nonionic active agents have a higher modifying effect than anionic and cationic active agents. As the chain transfer agent chelating agent, inorganic salt and the like, those known in emulsion polymerization are used.

The processing agent of the present invention further comprises a water-soluble resin such as polyvinyl alcohol, polyvinylpyrrolidone, polyacrylic acid, starch, carboxymethyl cellulose, hydroxyethyl cellulose or the like, and a filler such as synthetic silica, alumina or carbon charcoal for absorption. May be improved.
Also, urethane resin, acrylic resin, epoxy resin, melamine resin, styrene-acrylic copolymer resin, vinyl acetate resin, vinyl acetate ethylene copolymer resin, salt vinyl ethylene copolymer resin, styrene-butadiene copolymer resin, acrylonitrile-styrene-butadiene resin. You may mix resin etc. and adjust absorptivity.

[0012]

The processing agent of the present invention is internally added, impregnated,
By a method such as coating, it is adhered to a support such as paper, woven cloth, non-woven cloth, plastic film, wood board, metal board, glass board, etc., has sufficient adhesive strength, and has good printability and water resistance. Was obtained.

An example will be described below. Reaction Example 1 (1) Aqueous dispersion of polyester resin 520 parts (Plascoat Z-446, active ingredient 25%, manufactured by Kyowa Chemical Industry Co., Ltd.) (2) Surfactant 2 parts (Newcol 710, Nippon Emulsifier Co., Ltd.) (3) Vinyl monomer 20 parts methyl methacrylate 20 parts acrylamide 50 parts (4) Polymerization initiator benzoyl peroxide 2 parts (5) Ion-exchanged water 406 parts In a four-necked flask (1) (2) (4) (5) ),
After adding (3) little by little with stirring and thoroughly mixing, nitrogen gas is blown into this system to perform deoxidation. Then, the temperature was raised, for 5 hours at 65 to 85 ⁰ C. Stirring is continued until the temperature reaches room temperature to complete the reaction. Thus, active ingredient 20.0%, PH 4.7, viscosity 400cp
A stable aqueous resin dispersion of s was obtained.

Reaction Example 2 (1) 675 parts of polyester resin aqueous dispersion (Peth Resin 2000, manufactured by Takamatsu Yushi Co., Ltd., solid content 20)
%) (2) Surfactant 2 parts (Newcol 710, manufactured by Nippon Emulsifier Co., Ltd.) (3) Vinyl monomer butyl acrylate 15 parts Acrylamide 50 parts (4) Polymerization initiator benzoyl peroxide 2 parts (5) Ion Exchanged water 256 parts Proceeding the reaction as in Reaction Example 1, solid content 20%, PH5.
A stable aqueous dispersion having a viscosity of 0 and a viscosity of 500 cps was obtained.

Reaction Example 3 (1) Aqueous dispersion of polyester resin 520 parts (Plascoat Z-446) (2) Surfactant 2 parts (Newcol 710, manufactured by Nippon Emulsifier Co., Ltd.) (3) Vinyl monomer Methacrylic acid Methyl 70 parts (4) Polymerization initiator benzoyl peroxide 2 parts (5) Ion-exchanged water 406 parts The reaction was carried out in the same manner as in Reaction Example 1, solid content 20%, PH4.
5, a stable aqueous dispersion having a viscosity of 25 cps was obtained.

Reaction Example 4 (1) Polyester resin water dispersion 675 parts (Peth Resin 2000, manufactured by Takamatsu Yushi Co., Ltd., solid content 20)
%) (2) Surfactant 2 parts (Newcol 710, manufactured by Nippon Emulsifier Co., Ltd.) (3) Vinyl monomer butyl acrylate 65 parts (4) Polymerization initiator benzoyl peroxide 2 parts (5) Ion-exchanged water 256 Part The reaction was carried out in the same manner as in Reaction Example 1, solid content 20%, PH4.
5, a stable aqueous dispersion having a viscosity of 80 cps was obtained.

The aqueous dispersions obtained in Reaction Examples 1 to 4 were treated with PET.
Film (biaxially stretched polyester film, thickness 100
μm), synthetic paper (Yupo FPG-150, manufactured by Oji Oka Synthetic Paper Co., Ltd.), and fine paper (75 g / m ² , neutral paper) to a solid content of 3 g / m ² and dried. A sheet was prepared, a black ink was solidly printed on the sheet, and naturally dried for 1 hour. The photographic printing paper thus obtained was tested for the adhesion of the processing agent, the printability and the water resistance. The components of the black ink are dye (CI Acid Black 155) 3.5 parts diethylene glycol monoethyl ether 1.0 part N-methyl-α-pyrrolidone 20.0 parts 2,2′-thiodiethanol 20.0 parts Neugen P 0 1 part water is 55.4 parts.

The test method is as follows. (1) Adhesiveness Cellophane tape (manufactured by Nichiban) was attached on the processed surface of the recording sheet, and the remaining area of the processing agent was measured after the tape was rapidly separated in the 180 ^° direction. (2) Printability Black ink bleeding and repellency were observed. (3) Water resistance The photographic printing paper was immersed in water at 30 ⁰ C for 3 minutes, and the ink flow out and the density decrease were observed.

Reaction Examples 1 and 2 are Examples 1 and 2, Reaction Example 3,
4 as Comparative Examples 1 and 2, the results of the following tables were obtained for PET film (Table 1), synthetic paper (Table 2) and fine paper (Table 3).

[00020]

[Table 1]

[0021]

[Table 2]

[0022]

[Table 3]

The evaluation symbols in the table are as follows: printability: ○, bleeding, clear outline without repellence, etc., × bleeding, repellency, water resistance, ○ no change, Δ: ink flowed out, × completely dissolved in water.

As a result, the comparative example is insufficient in printability and water resistance. Compared to that, in all the examples, printability,
Both water resistance was good.

Claims (3)

[Claims] 1. A polyester resin aqueous dispersion modified with a polymer of a compound having a polymerizable double bond,
A processing agent for a receiving layer of an aqueous ink, which comprises copolymerizing one or more selected from unsaturated carboxylic acid amides and / or derivatives thereof in the polymer. 2. The processing agent for an aqueous ink receiving layer according to claim 1, wherein the polymer of the compound having a polymerizable double bond is used in an amount of 1 to 300% by weight based on the polyester resin. 3. A polyester resin to be modified is a polyethylene glycol carboxyl group, carboxylate,
The processing agent for an aqueous ink receiving layer according to claim 1, which contains a hydrophilic component such as a sulfonate or a sulfate ester salt.