JPH11268401A - Receptor material for ink jet printing - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form a receptor layer capable of being laminated without lamination of a primer, having good water absorption and water resistance of water soluble ink, and undergoing no drop in a receptor ability even when preserved under a high moisture environment. SOLUTION: The printing material is formed that 60-300 pts.wt. vinylpyrolidone block polymerized to 100 pts.wt. polyester resin of an average molecular weight of 4,000-30,000 consisting of (a) 50 mol.% diol, (b) 5-15 mol.% 5-sodium sulfoisophthalic acid, and 45-35 carboxylic acid except (c) (d), and a sodium group is substituted by alkaline earth.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a receiving material for ink jet printing.

[0002]

2. Description of the Related Art Ink-jet printing has advantages such as high-speed printing, non-contact printing on a printing substrate so that clear printing can be performed quietly and sharply, and printing on various substrates including plain paper. Is widely used.

Recently, plastic films and synthetic papers other than plain paper have been used as printing substrates for use in applications such as calendars and advertisements. However, since these substrates are non-hydrophilic, It was not possible to print with the conventional ink for inkjet printing which is an aqueous ink.

[0004] Therefore, a receiving material comprising a water-soluble resin such as polyvinyl alcohol and methyl cellulose and a filler such as silica, calcium carbonate and kaolin has been laminated on one surface of the substrate. However, laminating this receiving material requires laminating an undercoating agent, which has the disadvantage of complicating the process. Further, since this receiving material is opaque, it cannot be used for applications requiring transparency.

In order to improve such disadvantages, Japanese Patent Laid-Open No.
JP-A-165552 proposes a coating composition obtained by polymerizing a hydrophilic radically polymerizable vinyl monomer in a water-soluble or water-dispersed liquid in which a water-soluble or water-dispersible polyester resin and colloidal silica are mixed. ing.

[0006] The above coating composition does not have the above-mentioned drawbacks, has excellent water absorption of aqueous ink, has excellent water resistance of the composition layer, and is excellent as a receiving material for ink jet printing. However, when laminated on a substrate and stored in a humid environment such as during the rainy season, there was a disadvantage that the receiving performance of the aqueous ink was reduced.

[0007]

SUMMARY OF THE INVENTION In view of the above-mentioned drawbacks, an object of the present invention is to provide a water-based ink which can be laminated without laminating a primer, has excellent water absorption and water resistance of a water-based ink, and can be stored in a high humidity environment. Another object of the present invention is to provide a receiving material for ink-jet printing capable of forming a receiving layer in which the receiving performance of aqueous ink is not reduced.

[0008]

According to the present invention, there is provided a receiving material for ink-jet printing, comprising: (a) 50 mol% of a diol;
(B) 5 to 15 mol% of 5-sodium sulfoisophthalic acid and (c) 45 to 35 mol% of a dicarboxylic acid other than (b), having a weight average molecular weight of 4,000 to 30,00.
This is a receiving material for ink-jet printing obtained by subjecting 60 to 300 parts by weight of vinylpyrrolidone to 100 parts by weight of a polyester resin No. 0 and subjecting the sodium group to replacement with an alkaline earth metal.

The polyester resin comprises (a) 50 mol% of a diol, (b) 5 to 15 mol% of 5-sodium sulfoisophthalic acid and (c) a dicarboxylic acid other than (b).
5 to 35 mol%.

The diol (a) includes, for example, ethylene glycol, propylene glycol, 1,4-butanediol, 1,6-hexanediol, neopentyl glycol, cyclohexanedimethanol, bisphenol and the like.

As the dicarboxylic acid (c), any dicarboxylic acid other than 5-sodium sulfoisophthalic acid can be used. For example, terephthalic acid, isophthalic acid, phthalic acid,
Examples thereof include aromatic dicarboxylic acids such as naphthalene dicarboxylic acid, and aliphatic dicarboxylic acids such as adipic acid, succinic acid, sebastinic acid and dodecanoic acid, with aromatic dicarboxylic acids being preferred. Further, hydroxycarboxylic acids such as hydroxybenzoic acid and esters thereof may be used in combination.

The amount of 5-sodium sulfoisophthalic acid (b) and dicarboxylic acid (c) in the above polyester resin decreases as the amount of 5-sodium sulfoisophthalic acid (b) decreases, and when the amount increases, water resistance increases. 5-sodium sulfoisophthalic acid (b)
To 15 mol%, and the dicarboxylic acid (c) is 45 to 35 mol%.
Mol%.

The weight-average molecular weight of the above polyester resin is limited to 4,000 to 30,000, since water resistance decreases as the weight decreases and water absorption decreases as the weight increases. The method for producing the polyester resin is not particularly limited, and the above-mentioned diol (a), 5-sodium sulfoisophthalic acid (b) and a dicarboxylic acid (c) other than (b) are polycondensed by a conventionally known method. It can be obtained by:

In the invention of claim 1, vinylpyrrolidone is block-polymerized in the polyester resin. The amount of vinylpyrrolidone to be added is 60 to 300 parts by weight based on 100 parts by weight of the polyester resin since the ink absorption decreases as the amount decreases and the water resistance decreases as the amount increases.

When block-polymerizing vinylpyrrolidone, a vinyl monomer copolymerizable with vinylpyrrolidone may be copolymerized. Examples of the vinyl monomer include hydroxy (meth) acrylates such as 2-hydroxyethyl (meth) acrylate and 2-hydroxypropyl (meth) acrylate; ethylene glycol (meth)
Glycol (meth) acrylates such as acrylate and polyethylene glycol (meth) acrylate; (meth)
Acrylamide; methylol (meth) acrylamide;
Glycidyl (meth) acrylate; nitrogen-containing vinyl compounds such as vinylpyridine and vinylimidazole; unsaturated acids such as (meth) acrylic acid, maleic anhydride, itaconic acid and crotonic acid and salts thereof; aminoalkyl (meth) acrylates and the like Hydrophilic vinyl monomers such as quaternary ammonium salts and vinyl esters such as vinyl acetate and vinyl propionate; vinyl halides such as vinyl chloride and vinyl bromide; methyl (meth) acrylate, ethyl (meth) acrylate, and butyl (meth) Hydrophobic vinyl monomers such as alkyl (meth) acrylate such as acrylate; dimethylmethoxysilane; ethylene; propylene; styrene; butadiene.

When the amount of the hydrophilic vinyl monomer increases, the water resistance decreases, and when the amount of the hydrophobic vinyl monomer increases, the water absorption of the ink decreases. The amount is preferably 40% by weight or less of the total amount with vinylpyrrolidone.

As the method of block-polymerizing vinylpyrrolidone and, if necessary, vinyl monomer to the polyester resin, any conventionally known method may be employed. However, since the polyester resin is water-soluble or water-dispersible,
After dissolving or dispersing the polyester resin in water at 50 to 95 ° C. or water and a water-soluble organic solvent such as methanol or ethanol, a polymerization initiator and an emulsifier as needed are added, and then vinylpyrrolidone and optionally It is preferable to carry out polymerization by adding and mixing a vinyl monomer.

Examples of the polymerization initiator include water-soluble peroxides such as potassium persulfate, ammonium persulfate and hydrogen peroxide; oil-soluble peroxides such as benzoyl peroxide and t-butyl hydroperoxide; and azodiisobutyronitrile. And the like.

In the first aspect of the present invention, the sodium group in the polyester resin is replaced with an alkaline earth metal. Examples of the alkaline earth metal include beryllium, magnesium, calcium, strontium, barium and the like, with calcium being preferred.

The above substitution may be carried out before or after the block polymerization of polyvinylpyrrolidone. However, when the polyester resin is difficult to dissolve or disperse in water, it is preferably carried out after the block polymerization. The substitution can be easily performed by dissolving a water-soluble alkaline earth metal salt such as an alkaline earth metal halide in an aqueous solution or aqueous dispersion of a polyester resin.

It is preferable that all the sodium groups in the polyester resin be replaced by an alkaline earth metal.
The presence of free alkaline earth metal ions makes it difficult for the pigment-based aqueous ink to agglomerate and penetrate the aqueous ink,
It is preferable that the alkaline earth metal is added in an equivalent amount to the sodium group, since the image may be cracked.

The receiving material for ink-jet printing according to claim 2 comprises (a) 50 mol% of a diol, (b) 5 to 15 mol% of 5-sodium sulfoisophthalic acid and (c)
Consisting of 45 to 35 mol% of dicarboxylic acids other than (b),
100 parts by weight of a polyester resin having a sodium group substituted by an alkaline earth metal and having a weight average molecular weight of 4,000 to 30,000, and a weight average molecular weight of 40,000
~ 1,200,000 polyvinylpyrrolidone 60-3
It consists of 00 parts by weight.

The above-mentioned polyester resin is the same polyester resin as the above-mentioned polyester resin, and has a sodium group substituted by an alkaline earth metal.

The polyvinylpyrrolidone may be a homopolymer of vinylpyrrolidone or a copolymer of vinylpyrrolidone and a copolymerizable vinyl monomer. Examples of the vinyl monomer include the above-mentioned vinyl monomers, and the copolymerization ratio is preferably 40 mol% or less in the copolymer for the same reason as described above.

When the amount of polyvinylpyrrolidone is reduced, the ink absorbency is reduced, and when the amount is increased, the water resistance is reduced.
300 parts by weight.

In the receiving material for ink-jet printing according to claim 1 or 2, if free alkaline earth metal ions are present, the aqueous ink of the pigment type is hardly permeated with the pigment-based aqueous ink, so that it is difficult to penetrate the image. Therefore, it is preferable that the alkaline earth metal is added in an equivalent amount to the sodium group, but when the alkaline earth metal is excessively added or when polyvinyl chloride containing a metal soap-based stabilizer is used as the base material Preferably, zeolite particles are added to capture alkaline earth metal ions.

[0027] If the particle size of the zeolite particles is large, streaks are easily formed when the receiving layer is formed, so that the zeolite particles are preferably 3 µm or less. Further, when the addition amount is small, the alkaline earth metal ions cannot be sufficiently captured, and when the addition amount is large, the formability of the receiving layer is reduced. Therefore, based on 100 parts by weight of the receiving material for inkjet printing according to claim 1 or 2, 0.5-2
00 parts by weight is preferred.

The receiving material for ink-jet printing of the present invention may further contain, if necessary, a resin component such as an epoxy resin, an amino resin, an acrylic resin, or a urethane resin; a crosslinking agent such as an isocyanate compound and a silane coupling agent; Known additives such as a film assistant, a thickener, a leveling agent, an antistatic agent, an ultraviolet absorber, and an antioxidant may be added.

In order to obtain a recording paper for ink-jet printing by applying the ink-receiving material for ink-jet printing of the present invention to a substrate and forming an ink-receiving layer, for example, the ink-receiving material for ink-jet printing and, if necessary, the above additives Is dissolved or dispersed in water or water and a water-soluble organic solvent to obtain a solution or dispersion, and the solution or dispersion is applied to one or both surfaces of the substrate by a coating apparatus such as a roll coater, a gravure coater, a bar coater, or a knife coater. And drying.

Examples of the substrate include plastic films such as polyester, polyethylene, polypropylene, polyvinyl chloride, polystyrene, nylon, cellophane, and cellulose acetate; synthetic paper; plain paper;

The solid concentration of the above solution or dispersion is 1
0 to 50% by weight is preferable, and the thickness of the ink receiving layer is 1 to
30 μm is preferred.

[0032]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, the present invention will be described specifically with reference to examples.

Example 1, Comparative Example 1 50 mol of diethylene glycol, 46 mol of dimethyl terephthalate, 4 mol of dimethyl 5-sodium sulfoisophthalate, zinc acetate and antimony trioxide were supplied to a reaction vessel, and the mixture was heated at 170 to 220 ° C. for 3 hours. After the transesterification reaction, the polycondensation was carried out under reduced pressure while increasing the temperature to 260 ° C. to obtain a polyester resin having a weight average molecular weight of 11,000.

After adding and dissolving 20 parts by weight of the obtained polyester resin in 80 parts by weight of water, the temperature is raised to 80 ° C., and under a nitrogen atmosphere, with stirring, 20 parts by weight of vinylpyrrolidone, 3 parts by weight of methyl methacrylate and ammonium persulfate. 0.05 parts by weight was added and the mixture was polymerized for 3 hours to obtain a receiving material composition for inkjet printing of Comparative Example 1.

To the obtained receiving material composition for ink-jet printing of Comparative Example 1, an equivalent amount of calcium chloride to sodium contained was added to obtain a receiving material composition for ink-jet printing of Example 1.

The obtained ink-receiving material composition for ink jet printing is applied to a 100 μm-thick polyethylene terephthalate film with a bar coater so that the ink-receiving layer after drying has a thickness of 10 μm, and dried at 100 ° C. for 5 minutes. Thus, a recording paper for inkjet printing was obtained.

Example 2 The polyester resin 2 obtained in Example 1 was added to 80 parts by weight of water.
After adding and dissolving 0 parts by weight and 20 parts by weight of polyvinylpyrrolidone having a weight average molecular weight of 80,000, an equivalent amount of calcium chloride to sodium contained in the polyester resin is added to obtain the receiving material composition for inkjet printing of Example 1. Obtained.

Using the obtained receiving material composition for ink jet printing, a recording paper for ink jet printing was obtained in the same manner as in Example 1.

Example 3 To the receiving material composition for ink jet printing obtained in Comparative Example 1, 1.5 equivalents of calcium chloride contained in sodium was added to obtain a receiving material composition for ink jet printing. Using the obtained receiving material composition for inkjet printing, a recording paper for inkjet printing was obtained in the same manner as in Example 1.

Example 4 To the receiving material composition for ink jet printing obtained in Example 3, 10 parts by weight of zeolite particles having an average particle size of 2.56 μm were added to obtain a receiving material composition for ink jet printing. Using the obtained receiving material composition for inkjet printing, a recording paper for inkjet printing was obtained in the same manner as in Example 1.

Examples 5 and 6 The receiving material compositions for ink-jet printing obtained in Examples 1 and 4 were prepared using polyvinyl chloride (Panabeka Chemical Co., Ltd.
SH-100) 100 parts by weight, polyester plasticizer (P-300, manufactured by Asahi Denka Co., Ltd.) 30 parts by weight, Ba / Zn-based metal soap-based stabilizer (ZN100T, manufactured by Katsuta Kako Co., Ltd.) 5 parts by weight, benzotriazole-based ultraviolet ray A composition comprising 1 part by weight of an absorbent and 50 parts by weight of titanium oxide was applied to a 50 μm thick film formed by calendering and dried in the same manner as in Example 1 to obtain a recording paper for inkjet printing. .

Comparative Example 2 The polyester resin 2 obtained in Example 1 was added to 80 parts by weight of water.
After adding and dissolving 0 parts by weight, the temperature was raised to 80 ° C., and under a nitrogen atmosphere, 5 parts by weight of vinylpyrrolidone, 7.5 parts by weight of methyl methacrylate and 0.05 parts by weight of ammonium persulfate were added with stirring, and then 3 hours. Polymerized. Next, an equivalent amount of calcium chloride to sodium contained in the polyester resin was added to obtain a receiving material composition for inkjet printing.

Using the obtained ink-receiving material composition for ink-jet printing, a recording paper for ink-jet printing was obtained in the same manner as in Example 1.

Comparative Example 3 Polyester resin 2 obtained in Example 1 in 80 parts by weight of water
After adding and dissolving 0 parts by weight, the temperature was raised to 80 ° C., and 70 parts by weight of vinylpyrrolidone, 3 parts by weight of methyl methacrylate, and 0.1 part of ammonium persulfate were stirred with stirring in a nitrogen atmosphere.
05 parts by weight were added and polymerization was carried out for 3 hours. Next, an equivalent amount of calcium chloride to sodium contained in the polyester resin was added to obtain a receiving material composition for inkjet printing.

Using the obtained receiving material composition for ink jet printing, a recording paper for ink jet printing was obtained in the same manner as in Example 1.

The obtained recording paper for ink jet printing was printed with a dye-based water-based ink (MJIC7 (black), manufactured by Epson Corporation) and a pigment-based water-based ink (GO ink, manufactured by Graphtec) in accordance with JIS X9201. Physical properties were measured. The dye-based water-based ink was printed using an ink-jet printing machine for dye-based water-based ink (manufactured by Epson Corp., 810C), and the pigment-based water-based ink was printed using an ink-jet printing machine for pigment-based water-based ink (manufactured by Graphtec, JX1060).

(1) Ink absorbency: JIS X9201
The extent to which the ink was absorbed without bleeding in the black and dark print portion of the image identification symbol S6 of the print sample specified in the above was measured as a percentage. (2) Absorption of ink after humidification: recording paper at 30 ° C., humidity 9
The ink absorption was measured in the same manner as in the ink absorption except that the printing was carried out after standing for 24 hours under the condition of 0% RH.

(3) Ink Penetration: A filter paper was pressed against the image after printing, and the time until the ink stopped transferring to the filter paper was measured. (4) Water resistance: Drop a drop of water on the printing surface with a pipette.
0 seconds later, it was wiped off with tissue paper, and the remaining state of the film was observed.も の indicates that the coating remained, and x indicates that the coating was not dissolved.

(5) Image properties: The printed dots were visually observed, and the presence or absence of cracks of the dye in the dots was observed. Those without cracks were indicated by ○, and those with cracks were indicated by x. Table 1 shows the results when the dye-based aqueous ink was used, and Table 2 shows the results when the pigment-based aqueous ink was used.

[0050]

[Table 1]

[0051]

[Table 2]

[0052]

Since the constitution of the receiving material for ink-jet printing of the present invention is as described above, it can be easily laminated on various substrates without using a primer, and the obtained recording paper is water-based. Excellent ink absorbency and excellent water resistance of the coating. Further, the ink does not deteriorate even when stored in an environment with high humidity, and the acceptability of the aqueous ink does not decrease. Since the receiving material for ink jet printing according to the third aspect contains zeolite particles, it does not aggregate when printed with an aqueous ink (particularly, a pigment-based aqueous ink), and has good image quality.

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification code FI C09D 151/08 C09D 151/08 153/00 153/00

Claims (3)

[Claims] The weight average molecular weight of (a) 50 mol% of a diol, (b) 5 to 15 mol% of 5-sodium sulfoisophthalic acid and (c) 45 to 35 mol% of a dicarboxylic acid other than (b). 100 parts by weight of a 4,000 to 30,000 polyester resin is mixed with vinylpyrrolidone 60
A receiving material for ink-jet printing obtained by subjecting to 300 parts by weight to block polymerization and replacing a sodium group with an alkaline earth metal. 2. A composition comprising (a) 50 mol% of a diol, (b) 5 to 15 mol% of 5-sodium sulfoisophthalic acid and (c) 45 to 35 mol% of a dicarboxylic acid other than (b), wherein the sodium group is an alkali. 100 parts by weight of a polyester resin having a weight average molecular weight of 4,000 to 30,000 substituted by an earth metal and a weight average molecular weight of 40,000
2,000 to 1,200,000 polyvinylpyrrolidone 6
A receiving material for ink jet printing comprising 0 to 300 parts by weight. 3. The receiving material for ink jet printing according to claim 1, wherein 0.5 to 200 parts by weight of zeolite particles are added.