JPS5824493A - Recording material - Google Patents

Abstract

PURPOSE:To provide a recording material capable of obtaining a high-density image, by a method wherein a coating layer comprising a dye-adsorbing high polymer binder as a main ingredient is provided on a base containing a highly water-absorbing resin, so that an ink is absorbed extremely rapidly, and a solvent of the ink is absorbed but a colorant is left on at a surface layer. CONSTITUTION:The coating layer comprising a dye-adsorbing high polymer binder (e.g., a cationic polymer such as polyvinylpyridine or a polymer having an acidic group such as a styrene-itaconic acid copolymer in the case of direct dyes or acidic dyes, and a polymer having an anionic or basic group such as polysodium acrylate in the case of basic dyes) as a main ingredient is coated, preferably in an amount of 2-20g/m<2> (solid basis), on the base (e.g., pulp) containing a highly water-absorbing resin (e.g., a reaction product of corn starch, acrylamide and methylene bisacrylamide) to obtain the objective recording material. The resin is preferably used in an amount of 5-100pts.wt. per 100pts.wt. of the base. EFFECT:A sharp image excellent in resolution can be obtained.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a recording material (generally called a recording paper) used in inkjet recording. A small droplet of the recording liquid O is generated using various agents, and the droplet is attached to an arbitrary recording material such as paper to perform recording.

This inkjet recording method has shown rapid development in recent years as it makes it possible to record on a continuous basis with less noise. By the way, when recording with such an inkjet, ■ Absorption of the recording liquid (ink) into the recording material ■ The ink that adheres to the ink dots previously placed on the recording material does not flow onto the previous dot ■ The diameter of the ink dots does not become larger than necessary on the recording material ■ The ink dots The shape must be close to a circle, and the surrounding area must be smooth ■ The density of the ink dots must be high and the area around the dots must not be blurred ■ The whiteness of the recording material must be high and the contrast between the dots and the ink dots must be large ■ The color of the ink 01111 requirements are met, such as: ■ There is little scattering of ink drops around the ink dots; ■ There is little dimensional variation (for example, wrinkles, ridges) of the recording material before and after recording, etc. It is necessary to do so. In addition.

Satisfying these demands depends in large part on the characteristics of the recording material used, but the reality is that no recording material has hitherto been found that satisfies all of these required performances.

For example, the faster the ink is absorbed into the paper, the more spread out the ink dots will be on the surface. Also, if the ink penetrates into the paper, the dot density will be low9.
The object of the present invention is to provide a high-quality recording material for inkjet recording that satisfies almost all of the various requirements for recording using the inkjet recording method as described above. It is something to do.

The present invention advantageously achieves these objectives (h#)
, is characterized in that a coating layer containing a dye-adsorbing fastener as a main ingredient is provided on a base material containing a superabsorbent resin.

First, in the present invention #4, the super absorbent resin contained in the base material is a polymer compound that is insoluble in water and has water absorption properties, and has a water absorption capacity of 10 to 1000 times its own weight. refers to something that has

Examples of super absorbent resins using aAK of the present invention are as follows: ^ Cellulose ether is partially crosslinked or modified to make it insoluble in water (see JP-A No. 50-85689), for example.

Mu-(1) Reaction product of cellulose ether and N-methylolacrylamide 1 Person-(2) Cellulose ether,! : Reaction product with N-(acrylamidomethylene)-acedoyl 2-do, Mu1 (3) Reaction product of cellulose ether with N-(acrylamidomethylene)-methylurethane, 0 Addition product of starch or cellulose or amylose. Resin obtained by polymerizing or hydrolyzing a water-soluble monomer having a polybond property or a monomer that becomes water-soluble by hydrolysis and a cross-linking agent (see 41 Kokai No. 51-125468), e.g. , B-(1)) Reaction product of corn starch, acryland, and methylenebisacrylamide, B-(2) Reaction product of cellulose, acrylic acid, and N,N-methylenebisacrylamide, B-(3) Potato starch , acrylamide, N
, N-methylenebisacrylic acid reaction product, 0 Resin obtained by polymerizing and crosslinking starch and cellulose with the same monomers as in (2) and hydrolyzing (2)
(Refer to 9 Kaikai No. 52-59890) For example.

0-(1) )? Sorghum starch, reaction product of methacrylic acid, 0-(movement) Rice starch, reaction product of sulfopropyl methacrylate, 0- (3) Reaction product of wheat starch, methacrylic acid, acrylic acid sodium salt, (l vinyl ester Resin obtained by reacting a crosslinking agent with a saponified copolymer of and ethylenically unsaturated carboxylic acid or its derivative (see JP-A-52-14689) For example, D-+1) Vinyl acetate-acrylic D-(2) Reaction product of vinyl acetate-methyl acrylate copolymer and 1,6-hexanethiol diglycidyl ether, (11 vinyl ester) A copolymer saponified product of and ethylenically unsaturated carboxylic acid or a derivative thereof is dried from a water-containing state (see FR Publication No. 1852-27455). For example, If-(1) Vinyl alcohol-acrylic acid copolymer Sodium salt of polymer (t) [saponified copolymer of vinyl ester with 1114 structure and ethylenically unsaturated carboxylic acid or derivative thereof (JP-A-52-65597, see f! [)] For example, F-0) a silicide of vinyl acetate-methyl acrylate copolymer, a saponified product of vinyl acetate-methyl acrylate copolymer using ethylene glycol diacdalate as a crosslinking agent, ((( 1Saponified copolymer consisting of vinyl ester and acrylic (methacrylic) acid0<*Kaimei 53-5029
For example, 0- (1) Saponified product of vinyl acetate-methyl acrylate copolymer, G-(1 vinyl acetate-methyl methacrylate copolymer O
Saponified product, I Self-crosslinking amount Acrylic acid alkali metal salt PolyY-(4
1111i83-46389 (Reference) (I)
Crosslinked polyethylene oxide) Denopone-acrylonitrile glatt polymer O hydrolyzate Polyvinyl alcohol is sulfated or phosphorylated in the presence of a bulk compound.

■ Within the cross-linked poly(meth)acrylate value, the particle size is in the range Kr of 0.02 to 100 μm.
The base material containing a super absorbent resin of the present invention generally refers to a good paper in which a super absorbent resin is dispersed in pulp. This type of paper can be easily obtained by adding and dispersing fine powder of a super absorbent resin into pulp using the Aichi O paper making method.◎Additional amount of super absorbent resin to pulp is preferably from 5 to 100 parts per 100 parts by weight of paprophage.
Parts by weight. In addition, various additives such as fillers such as Merck, clay, calcium bicarbonate, silica, barium sulfate, various surfactants, preservatives, etc. can be used in combination with this paper pulp. Furthermore, it is not preferable to use a large amount of the sizing agent because it reduces the effect of the present invention, but it may be used in combination as long as it is used in a small amount.

The base material in the present invention is usually paper, but it is not limited to this and may be made of non-woven fabric or plastic film.

Book! 1 #4 A polymer binder having dye adsorption properties refers to a polymer binder having a negative ionicity opposite to that of the dye used in I/I. In other words, in the present invention, the dye of the ink is -80,M and or -OOOMCM are alkali metals,
-NH, various amines), use a polymeric binder with a cationic or acidic group; conversely, the dye is a basic dye with a quaternary ammonium base in the molecule. In this case, a polymer binder having an anionic or basic group is used.In addition, in the present invention, a dye-adsorbing polymer binder that forms a dye-adsorbing layer corresponding to the surface layer is specifically exemplified. Examples of cationic polymers include 4Ii ammonium salt type polymers, polyvinylpyridine, vinyl vinylidene chloride, chloroacetate copolymers, polyvinylpyrrolidone, and positive starch. Meth)acrylic acid, styrene-maleic W18 polymer, styrene-itaconic acid copolymer, methyl methacrylate-methacrylic acid copolymer, methyl methacrylate-α-7enyl acrylic acid copolymer, etc. are used.

Also, poly! having an anionic or basic group. In addition to the above-mentioned dye-adsorbing polymer binder (cationic or anionic polymer), various additives 9 such as clay, silica, Pigments such as calcium bicarbonate, oxide, barium sulfate, Merck, Alden, Natin, etc., various surfactants, preservatives, etc. can be added as appropriate. The components are mixed together with water and/or various organic solvents, prepared as a coating composition using a known dispersion device such as a ball mill or sand kil, and generally coated by a known method such as a roll coating method or rotadopar coating method. α59/ in solid content
Apply paint in an amount of it to Sol/wl consistency. Practically speaking, it is preferable to apply the coating at a rate of 211/d to 20 l/yt.

After this unpleasant coating layer has been applied, Ik is applied according to the conventional method.
Dry the cloth layer O.

The ink used for recording on the recording material of the present invention contains a water fII dye as a colorant and water as a solvent as essential components.

As water-soluble dyes, known direct dyes, acid dyes, and basic dyes are preferably used. The content of these colorants in the ink is 0.5 to 3% by weight, preferably 1 to 20% by weight. In addition to the water mass, the SM of the ink includes glycerin, ethylene glycol, ilopyrenoglycol, diethylene glycol, glycols such as thiodiglycol, methyl calpitol, ethyl calpitol, butyl calpitol, methyl cellosolve, ethyl seronulf, and triethylene. Glycol ethers such as glycol monomethyl ether and triethylene glycol monoethyl ether, N-methyl-2-pyrrolidone,
The preferred content of water in the ink is 10 to 90 percent by weight, which can be used in combination with a water-soluble solvent such as a nitrogen-containing solvent such as 1.3 dimethylimidazolidinone or formamide.

By using the recording material of the present invention in combination with such inks, (1) the ink is absorbed extremely quickly, so even if dots overlap, the ink does not flow out (2) the ink solvent is rapidly absorbed into the substrate, but the dye, which is a coloring agent, is caught on the surface layer, resulting in an extremely high image density.

(The shape of the dot is close to a circle, the periphery is smooth, there are few bleeds, and a sharp image with excellent resolution can be obtained.

etc.O shows excellent effects.

The present invention will be explained in more detail with reference to Examples below.

Examples 1 to 10 100 parts by weight of raw material pulp LBKP was refined with a refiner to a freeness of 4001111, and fine powder of the super absorbent resin shown in Table 1 was added thereto. Amount s o Ild 0 paper was made into paper using a paper machine, and the coating composition shown in the surface layer in Table 2 was dispersed on one side of the paper using a ball mill, and then coated and dried at a solid content of 517 d. The nine recording materials thus obtained were shown in Table 3 with ink relatives, and the nine inks were subjected to an inkjet process, and the results are shown in Table 1t-4. - The results of printing with the inks of Examples 1 to 4 in Table 3 on commercially available paper indicated by IK are shown in 1N-6. From the results, the recording material of each example has a resolution (do ν111 do y) @ change. 1.0, which was significantly superior in both fixing time and water resistance, Table-
In 1, the dot looseness was measured using Sakura Micro De/
Using Sitner PDM-5 (Konishi Roku Photo Industry Co., Ltd.), the slit width is 30μ, the width is 30μ, and the electric speed in the X-axis direction is lli! Ion/see.

Chart feed speed l/Sect The sample feed speed ratio to the chart is the result of measurement at 100 times magnification. The dot pole is determined by measuring the diameter of the printed dot using a stereomicroscope, and the fixing speed is determined by the ink cartridge.

After printing with a printing device, the printed area was rubbed with a finger, and the time required until the non-printed area was no longer smudged by the printed ink was measured.

Also, the ink ejection opening diameter (orifice diameter) of the inkjet recording device used here is 50μ.0 Table-1 Note 1) l! It is exemplified in the Jl book and indicated by the nine symbol.

Table-2 Table-3 Table-4

Claims (1)

[Claims] Dye adsorption on the base material containing super absorbent resin