DE60209284T2 - Ink jet recording sheet - Google Patents

Description

BACKGROUND OF THE INVENTION:

Field of the invention:

The The present invention relates to a recording material useful in Ink jet recording, wherein a liquid ink, such as a water-based ink and an oil-based ink, a solid ink which is solid at ambient temperature, which is supplied to the printing operation after reflow, or the like is used. More specifically, the present invention relates to an ink jet recording sheet with excellent ink receptivity.

Description of the state of the technique:

In Recently, in the wake of the rapid growth of the information technology industry developed various information processing systems. consequently were also recording methods and suitable for recording systems Devices developed and put into practical use.

Under The above-mentioned recording method does not become the ink-jet recording method only in the office, but also widely used in the private sector. The reason therefor can be seen in many factors, such as the possibility recording on different types of recording materials, the relative cost-effectiveness the hardware (devices), their compactness and their superiority Low noise.

Furthermore can in the course of the present Trends to high resolution in ink jet printers, a recording material is obtained, which provides high quality photographic-like images. Furthermore were with the development of hardware (devices) different types of recording sheets for the Inkjet recording developed.

in the In general, the above recording sheets for ink jet recording require several Properties. These are (1) rapid drying properties (rapid Ink absorbency); (2) adequate and even Ink dot size (Absence of bleeding); (3) good graininess; (4) excellent point health; (5) high color density; (6) high saturation (Lack of dullness); (7) good light and water resistance in the printing area; (8) high whiteness; (9) good storage stability (absence of yellowing even after long-term storage); (10) good stability without deformation (sufficient low wave formation) and (11) good propulsion properties in the Hardware. When a glossy photographic paper as a recording material for Achieving photography-like high-quality images is used the recording material must be in addition to the above Properties such as the qualities of gloss, surface smoothness and Paper-like feel similar to in silver salt photography.

to Improvement of these characteristics has become an ink jet recording sheet with a porous one Structure in its image-receiving layer with excellent ink absorbency (i.e., rapid drying) and high gloss developed and practical Application brought.

JP-A-62-178384 and JP-B-3-24905 propose a recording material containing a Image-receiving layer containing silica particles whose surfaces are treated with a silane coupling agent. Although the weather resistance with decreasing surface activity of the silica particles is improved, however, the film strength of the image-receiving Layer weakened, because the cohesive force between the silica particles is also reduced.

There the silica dispersion when mixed with a binder, such as For example, PVA, aggregated, moreover increases the viscosity at a point where it deteriorates the stability of the dispersion. This is the size the silica particles in the dispersion are large and the gloss, the coating film strength, Speed of ink absorption, water resistance, print density and the like are adversely affected. Among these adversely affected Properties in particular the print density is so influenced that it decreases drastically.

JP-A-2001-10209 proposes an ink jet recording paper containing inorganic fine pigment particles, a silane coupling agent having an ammonium structure and a cationic resin. Since such an ink jet recording sheet with inorganic fine particles with a cationic resin in one However, if the solution is coated on the surface of a support, aggregation is caused between the cationic resin and the inorganic fine particles having an anionic charge, and hence the desired properties of the ink jet recording paper can not be fully realized.

JP-A Nos. 8-39927, 2000-309159 and 2000-313164 disclose an ink jet recording sheet, in that at the time of cationic polymerization, a chain transfer agent is used. However, these use the chain transfer agent for Adjustment of the degree of polymerization and not for improvement the dispersion properties of the fine inorganic pigment particles.

JP-A Nos. 10-181190, 10-181191, 11-321079 and 11-348409 disclose one Dispersion of fine inorganic particles in the presence of a cationic Resin. However, these references mention the ends of the polymer Not.

JP-A-63-260477 discloses a recording material comprising a polyamine compound with a surface activity by introduction an alkyl group of 6-18 Carbon atoms in the end group of the compound includes. The polyamine compound is similar to the polymer used in the invention, however, it is not used as a mordant. In addition, silica is in the Recording material no necessary component.

As mentioned above, became present not an inkjet recording sheet yet with a solid image-receiving layer without cracking or the same and good ink receptivity, which is a high-resolution image delivers that highly water resistant and above beyond Bleeding over time is consistent and excellent Printing density, sharpening and gloss shows proposed.

SUMMARY OF THE INVENTION:

The The aim of the present invention is the solution of the above-mentioned conventional Problems while achieving the following goals.

One first invention The aim is to provide an ink jet recording sheet with high image density.

One second invention The aim is to provide a solid ink jet recording sheet without cracking or the like, the good ink receptivity has, a high-resolution Picture delivers and excellent gloss, water resistance and durability across from Bleeding after printing and even under light irradiation in the Sunlight, fluorescent light or the like excellent in light resistance has.

According to the invention an ink jet recording material is provided which has a carrier and an image-receiving layer comprising the inorganic fine ones Pigment particles and a cationic polymer at its end has a group selected is from an alkyl group having a total of 4-36 carbon atoms, one Aryl group and an aralkyl group contains.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS:

Ink-jet recording sheet:

An ink-jet recording sheet of the present invention comprises an image-receiving layer comprising fine inorganic pigment particles and a cationic polymer having at its end a group selected from an alkyl group having a total of 4-36 carbon atoms, an aryl group and an aralkyl group (hereinafter also referred to as "cationic polymer Polymer "). When the cationic polymer of the present invention is added to a dispersion of an inorganic pigment at the time of dispersing the inorganic pigment in the production of the image-receiving layer, the aggregation of the inorganic pigment, for example, the aggregation of the pigment at the time of mixing it with a water-soluble resin, such as For example, polyvinyl alcohol or the like can be prevented, and hence a coating solution having a low viscosity and a small dispersion particle size can be prepared. In the case of a dispersion having a low viscosity and a small particle size, the properties of the ink-jet recording sheet in which it is used, such as gloss, can prevent the formation of cracks in the image The ink layer, the ink absorption speed, the water resistance, and the bleeding-out resistance are improved over time, and an extremely high-density ink jet recording sheet can be provided.

If an inventive cationic polymer in the dispersion of fine inorganic In addition, pigment particles can be used in comparison to in the case of exclusive dispersion of fine inorganic Pigment particles using a known cationic polymer Improves the print density by adding a small amount of the polymer become. This can cause discoloration the image-receiving layer, which in the case of using a large Amount of the known cationic polymer occurs, and also the Deterioration of light resistance and the film strength of the image-receiving layer and the generation bleeding can be avoided over time.

Image-receiving layer:

First, be explains the materials contained in the image-receiving layer. The invention contains image-receiving layer at least one invention cationic polymer and fine inorganic pigment particles and contains preferably a water-soluble Resin, a crosslinking agent used to crosslink the water-soluble Resin is capable, and an organic mordant. Further, after Need to include various additives.

Cationic according to the invention Polymer:

The invention cationic polymer has at its end a group that is selected from an alkyl group of 4-36 Carbon atoms, an aryl group and an aralkyl group. The invention cationic polymer may be any of these groups at least have an end. It can have these groups at both ends, however, it is in terms of improving the dispersion property and the fluidity of the fine inorganic pigment particles prefers that the group only exists at one end. Further, the alkyl group, aryl group and aralkyl group has a branched structure or cyclic structure to have.

The total number of carbon atoms of the alkyl group is 4-36 and preferably 8-18. When the number of carbon atoms is less than 4, the aggregation of the fine inorganic pigment particles can not be prevented. If it is more than 36, the solubility of the cationic polymer in water or alcohol is lowered, and such a cationic polymer may be unsuitable for production. Examples of the alkyl group include 1-butyl group, 1-pentyl group, 1-hexyl group, 1-heptyl group, 1-octyl group, 1-nonyl group, 1-decyl group, 1-undecyl group, 1-dodecyl group, 1-tridecyl group, 1-tetradecyl group, 1-pentadecyl, 1-hexadecyl, 1-heptadecyl, 1-octadecyl, 1-nonadecyl, 1-eicosyl, 1-docosyl, 1-hexacosyl, 1-triacontyl, 1-hexatriacontyl, sec-butyl, isobutyl, tert-butyl, Neopentyl group, 2-methyl-1-butyl group, 3-methyl-1-butyl group, 2-ethyl-1-butyl group, 3,3-dimethyl-1-butyl group, 2-methyl-1 pentyl group, 3-methyl-1-pentyl group, 4-methyl-1-pentyl group, 2-propyl-1-pentyl group, 2,4,4-trimethyl-1-pentyl group, 2-ethyl 1-hexyl group, 3,5,5-trimethyl-1-hexyl group, 3,7-dimethyl-1-octyl group, 2-pentyl group, 3-pentyl group, 2-hexyl group, 3-hexyl group, 2- Heptyl group, 2-octyl group, 3-octyl group, 2-nonyl group, 2-decyl group, 4-decyl group, 2-undecyl group, 2-dodecyl group, 2 Tetradecyl group, 2-hexadecyl group, 3-methyl-2-butyl group, 3,3-dimethyl-2-butyl group, 3-methyl-2-pentyl group, 4-methyl-2-pentyl group, 2 Methyl 3-pentyl group, 4,4-dimethyl-2-pentyl group, 4,4-dimethyl-2-methyl-2-pentyl group, 2,2-dimethyl-3-pentyl group, 2 , 4-Dimethyl-3-pentyl group, 5-methyl-2-hexyl group, 2-methyl-3-hexyl group, 6-methyl-2-heptyl group, 4-methyl-3-heptyl group , 2,6-dimethyl-4-heptyl group, tert-amyl group, 2,3-dimethyl-2-butyl group, 2-methyl-2-pentyl group, 3-methyl-3-pentyl group, 3 Ethyl 3-pentyl group, 2,3-dimethyl-3-pentyl group, 3-ethyl-2,2-dimethyl-3-pentyl group, 2-methyl-2-hexyl group, 3.7 Dimethyl 3-octyl group, cyclohexyl group and the following compound (A):

The Number of carbon atoms of the aryl group is preferably 6-14 and more preferably 6-10. Examples for the Aryl group include a phenyl group, tolyl group, xylyl group, Naphthyl group, biphenyl group and alkylphenyl.

The Number of carbon atoms of the aralkyl group is preferably 7-15, further preferably 7-11. examples for the aralkyl group includes a benzyl group, phenethyl group, Diphenylmethyl group, triphenylmethyl group and α- or β-styryl group.

As the cationic polymer of the present invention, those of the following general formula (1) are particularly preferable:

In of the general formula (1), X is a single bond or a divalent one Compound and R is a straight, branched or cyclic Alkyl group with 4-36 Carbon atoms, an aryl group or an aralkyl group. A is at least one kind of repeating unit with one Cation and B is at least one kind of repetitive unit, which is copolymerizable with A. m and n each represent the mole fraction of component A or component B, and 0.2 ≦ m ≦ 1.0, 0 ≦ n ≦ 0.8 and m + n = 1.0.

The Copolymer comprising units A and B can be any of be selected from a random block and graft copolymer.

In of the general formula (1), X is a single bond or a divalent one Linking group. The divalent linking group is not very special limited, and, for example, a divalent linking group is the following general formula (8) preferred.

General formula (8):

• -YR ⁸ -

In the general formula (8), R ^{8 is} a single bond or a C _1-8 alkylene group which may have a side chain, and Y is a divalent linking group.

The Number of carbon atoms in the alkylene group is 1-8 and preferably 1-4. The Alkylene group may have a side chain. Examples of the alkylene group include methylene, ethylene, propylene, tetramethylene, hexamethylene and octamethylene. Close examples of the side chain a methyl group, ethyl group, propyl group, butyl group, phenyl group, Methoxy group, ethoxy group and phenoxy group, and a methyl group, Ethyl group and methoxy group are preferred.

Y is a divalent linking group. Close examples for this an ether, a thioether, an amine, an ester, an amide, a Thioester, an ester carbonate, a urea, a thioester carbonate, a dithioester carbonate, an aromatic ring and a heterocycle one.

The Combination wherein X is a single bond or a divalent linking group of the general formula (8) and Y is an ether, a thioether, an ester or an amide is preferred. Particularly preferred is a single bond or a divalent linking group of the general formula (8), which has an ether or an ester as Y.

specific examples for the divalent linking groups X are given below, however, the invention is not limited thereto.

In of the general formula (1), R is a linear, branched or cyclic Alkyl group with a total of 4-36 Carbon atoms, an aryl group or an aralkyl group.

The Total number of carbon atoms in the alkyl group is 4-36 and preferably 8-18. If the number of carbon atoms is less than 4, can the aggregation of the fine inorganic pigment particles is not avoided become. If they are higher than 18, the solubility becomes of the cationic polymer in water or alcohol, and such a cationic polymer may be unsuitable for production be. examples for the alkyl groups include a 1-butyl group, 1-pentyl group, 1-hexyl group, 1-heptyl group, 1-octyl group, 1-nonyl group, 1-decyl group, 1-undecyl group, 1-dodecyl group, 1-tridecyl group, 1-tetradecyl group, 1-pentadecyl group, 1-hexadecyl group, 1-heptadecyl group, 1-octadecyl group, 1-nonadecyl group, 1-eicosyl group, 1-docosyl group, 1-hexacosyl group, 1-triacontyl group, 1-hexatriacontyl group, sec-butyl group, isobutyl group, tert-butyl group, Neopentyl group, 2-methyl-1-butyl group, 3-methyl-1-butyl group, 2-ethyl-1-butyl group, 3,3-dimethyl-1-butyl group, 2-methyl-1-pentyl group, 3-methyl-1-pentyl group, 4-methyl-1-pentyl group, 2-propyl-1-pentyl group, 2,4,4-trimethyl-1-pentyl group, 2-ethyl-1-hexyl group, 3,5,5-trimethyl-1-hexyl group, 3,7-dimethyl-1-octyl group, 2-pentyl group, 3-pentyl group, 2-hexyl group, 3-hexyl group, 2-heptyl group, 2-octyl group, 3-octyl group, 2-nonyl group, 2-decyl group, 4-decyl group, 2-undecyl group, 2-dodecyl group, 2-tetradecyl group, 2-hexadecyl group, 3-methyl-2-butyl group, 3,3-dimethyl-2-butyl group, 3-methyl-2-pentyl group, 4-methyl-2-pentyl group, 2-methyl-3-pentyl group, 4,4-dimethyl-2-pentyl group, 4,4-dimethyl-2 methyl-2-pentyl group, 2,2-dimethyl-3-pentyl group, 2,4-dimethyl-3-pentyl group, 5-methyl-2-hexyl group, 2-methyl-3-hexyl group, 6-methyl-2-heptyl group, 4-methyl-3-heptyl group, 2,6-dimethyl-4-heptyl group, tert-amyl group, 2,3-dimethyl-2-butyl group, 2-methyl-2-pentyl group, 3-methyl-3-pentyl group, 3-ethyl-3-pentyl group, 2,3-dimethyl-3-pentyl group, 3-ethyl-2,2-dimethyl-3-pentyl group, 2-methyl-2-hexyl group, 3,7-dimethyl-3-octyl group, Cyclohexyl group and the above-described compound (A).

The Number of carbon atoms of the aryl group is preferably 6-14 and more preferably 6-10. Examples for the Aryl group include a phenyl group, tolyl group, xylyl group, Naphthyl group, biphenyl group and alkylphenyl group.

The Number of carbon atoms of the aralkyl group is preferably 7 to 15, and more preferably 7 to 11. Examples of the aralkyl group include a benzyl group, phenethyl group, diphenylmethyl group, Triphenylmethyl group and α- or β-styryl group one.

specific examples for R in the general formula (1) include a 1-butyl group, 1-pentyl group, 1-hexyl group, 1-heptyl group, 1-octyl group, 1-nonyl group, 1-decyl group, 1-undecyl group, 1-dodecyl group, 1-tridecyl group, 1-tetradecyl group, 1-pentadecyl group, 1-hexadecyl group, 1-heptadecyl group, 1-octadecyl group, 1-nonadecyl group, 1-eicosyl group, 1-docosyl group, 1-hexacosyl group, 1-triacontyl group, 1-hexatriacontyl group, sec-butyl group, isobutyl group, tert-butyl group, Neopentyl group, 2-methyl-1-butyl group, 3-methyl-1-butyl group, 2-ethyl-1-butyl group, 3,3-dimethyl-1-butyl group, 2-methyl-1-pentyl group, 3-methyl-1-pentyl group, 4-methyl-1-pentyl group, 2-propyl-1-pentyl group, 2,4,4-trimethyl-1-pentyl group, 2-ethyl-1-hexyl group, 3,5,5-trimethyl-1-hexyl group, 3,7-dimethyl-1-octyl group, 2-pentyl group, 3-pentyl group, 2-hexyl group, 3-hexyl group, 2-heptyl group, 2-octyl group, 3-octyl group, 2-nonyl group, 2-decyl group, 4-decyl group, 2-undecyl group, 2-dodecyl group, 2-tetradecyl group, 2-hexadecyl group, 3-methyl-2-butyl group, 3,3-dimethyl-2-butyl group, 3-methyl-2-pentyl group, 4-methyl-2-pentyl group, 2-methyl-3-pentyl group, 4,4-dimethyl-2-pentyl group, 4,4-dimethyl-2-methyl-2-pentyl group, 2,2-dimethyl-3-pentyl group, 2,4-dimethyl-3-pentyl group, 5-methyl-2-hexyl group, 2-methyl-3-hexyl group, 6-methyl-2-heptyl group, 4-methyl-3-heptyl group, 2,6-dimethyl-4-heptyl group, tert-amyl group, 2,3-dimethyl-2-butyl group, 2-methyl-2-pentyl group, 3-methyl-3-pentyl group, 3-ethyl-3-pentyl group, 2,3-dimethyl-3-pentyl group, 3-ethyl-2,2-dimethyl-3-pentyl group, 2-methyl-2-hexyl group, 3,7-dimethyl-3-octyl group, cyclohexyl group, phenyl group, naphthyl group, Tolyl group, benzyl group, phenethyl group and those described above Compound (A).

In of the general formula (1), A is at least one kind of itself repeating unit that has a cation. A is not special limited and is preferably a repeating unit of the following Formulas (I) to (IV).

(I) Repeating unit of the following general formula (2)

In the general formula (2), R ^{1 is} a hydrogen atom or an alkyl group having 1-4 carbon atoms, and R ² , R ³ and R ⁴ each independently represent a hydrogen atom or an alkyl group having 1-18 carbon atoms which may have a substituent , or which may be linked together to form a saturated or unsaturated ring, an aryl group or an aralkyl group. Z is -O- or -NH- and Y ² is a divalent linking group having a total of 1-8 carbon atoms which may contain a heteroatom. X ^- is an anion.

In the general formula (2), R ^{1 is} a hydrogen atom or an alkyl group having 1-4 carbon atoms. If the number of carbon atoms is more than 4, it may be difficult to obtain a polymer. The number of carbon atoms of the alkyl group is preferably 1-2. Examples of the alkyl group include a methyl group, ethyl group, propyl group, isobutyl group and n-butyl group. R ¹ is preferably a hydrogen atom or a methyl group.

In the general formula (2), R ² , R ³ and R ⁴ each independently represent a hydrogen atom or an alkyl group having 1-18 carbon atoms, an aryl group or an aralkyl group. The alkyl group, the aryl group and the aralkyl group may have a substituent. Examples of the substituent include a halogen atom, a hydroxyl group, an amino group, an ester group, an ether group and an amide group.

The Number of carbon atoms of the alkyl group is 1-18, preferably 1-8. If the number of carbon atoms is more than 18, the solubility becomes of the cationic polymer in water or alcohol is reduced and the desired Properties can can not be achieved. Close examples of the alkyl group a methyl group, ethyl group, propyl group, butyl group, hexyl group, Cyclohexyl group, octyl group, decyl group, dodecyl group, tetradecyl group and octadecyl group, and a methyl group, ethyl group, butyl group, Hexyl group and cyclohexyl group are preferred.

The Number of carbon atoms in the aryl group is preferably 6-14, more preferably 6-10. examples for the aryl group include a phenyl group, tolyl group, xylyl group and naphthyl group, and a phenyl group and tolyl group prefers.

The Number of carbon atoms of the aralkyl group is preferably 7-15 and more preferably 7-11. Examples for the Aralkyl group include a benzyl group, phenethyl group, diphenylmethyl group, Triphenylmethyl group and α- or β-styryl group a, and a benzyl group is preferred.

In of the general formula (2) is Z is -O- or -NH-.

In the general formula (2), Y ^{2 is} a divalent linking group having a total of 1-8 carbon atoms which may contain a hetero atom. Examples of the hetero atom include an oxygen atom, a nitrogen atom, a sulfur atom, a silicon atom and a phosphorus atom, and an oxygen atom, a nitrogen atom and a sulfur atom are preferable. The total number of carbon atoms of Y ² is preferably 2-6. Examples of the divalent linking group include a methylene group, ethylene group, propylene group, tetramethylene group, hexamethylene group, xylylene group and 3-oxapentamethylene group.

In the general formula (2), X ^{- is} an anion. The anion is not particularly limited and examples include F ^- , Cl ^- , Br ^- , I ^- , AcO ^- , NO ₃ ^- , SO ₄ ^2- , HSO ₄ ^- , MeSO ₄ ^- , PO ₄ ^3- , HPO ₄ ^{2 -} , H ₂ PO 4 ^- , TsO ^- , CH ₃ SO ₃ ^- , ClO ₄ ^- , BF ₄ ^- , PF ₄ ^- , CH ₃ CH ₂ CO ₂ ^- , Ph-CO ₂ ^- , (CO ₂ ) ₂ ^2- and a (meth) acrylate anion.

specific examples for the repeating unit of the general formula (2) are given below, however, the invention is not limited thereto.

(II) A repeating unit of the following general formula (3):

In the general formula (3), R ^{5 is} a hydrogen atom or a methyl group, and preferably a hydrogen atom. R ² , R ³ , R ⁴ and X ^- are defined as in the general formula (2).

Specific examples of the repeating unit of the general formula (3) are as follows but the invention is not limited thereto.

(III) A repeating unit of the following general formula (4) or (5)

In the general formulas (4) and (5), R ^2, R ³ and X ^- is as defined in the general formula (2).

specific examples for the repeating unit of the general formula (4) or (5) are given below, but the invention is not hereto limited.

(IV) A repeating unit of the following general formula (6) or (7):

In the general formulas (6) and (7), n is 0 or 1, preferably 1, and R ² , R ³ , R ⁴ and X ^- are as defined in the general formula (2).

specific examples for the repeating unit of the general formula (6) or (7) are given below, but the invention is not hereto limited.

In the general formula (1), B is at least one kind of a repeating unit which is copolymerizable with A. B is not particularly limited, and examples thereof include an aromatic vinyl compound (such as styrene, α-methylstyrene, p-hydroxystyrene, chloromethylstyrene and vinyltoluene), an alkyl (meth) acrylate (e.g., methyl (meth) acrylate, ethyl (meth) acrylate , n-butyl (meth) acrylate, isobutyl (meth) acrylate and 2-ethylhexyl (meth) acrylate), an alkylaryl (meth) acrylate (such as benzyl (meth) acrylate), a substituted alkyl (meth) acrylate (for example, glycidyl (meth) acrylate, 2-hydroxyethyl (meth) acrylate, dimethylaminoethyl (meth) acrylate and dimethylaminopropyl (meth) acrylate), an alkyl (meth) acrylamide (such as (meth) acrylamide, dimethyl (meth) acrylamide, N-isopropyl ( meth) acrylamide, n-butyl (meth) acrylamide, tert-butyl (meth) acrylamide and tert-octyl (meth) acrylamide), a substituted alkyl (meth) acrylamide (such as dimethylaminoethyl (meth) acrylamide and dimethylaminopropyl (meth) acrylamide ), a vinyl cyanide (such as (meth) acrylonitrile and α-chloro racrylonitrile), a vinyl carboxylate (such as vinyl acetate, vinyl benzoate and vinyl formate), an aliphatic conjugated diene (such as 1,3-butadiene and isoprene) and a polymerizable oligomer (such as a polyme methyl methacrylate oligomer having a methacryloyl group at one end thereof, a polystyrene oligomer having a methacryloyl group at one end thereof, and polyethylene glycol having a methacryloyl group at one end thereof).

In represent the general formula (1) m and n are each the molar fraction of component A and the component B, and 0.2 ≦ m ≦ 1.0 and 0 ≦ n ≦ 0, 8, wherein m + n = 1.0. The relationship of m: n is preferably 0.4: 0.6-1.0: 0 and more preferred 0.5: 0.5-1.0: 0th

The Number average molecular weight of the inventive cationic Polymer is preferably 1,000-20,000, more preferably 1,000-10,000, and more preferably 1,500-10,000. When the molecular weight is less than 1,000 or more than 20,000 is, can not aggregation of fine inorganic pigment particles be prevented.

The mass ratio the fine inorganic pigment particles and the cationic polymer according to the invention in the image-receiving layer is preferably 1: 0.001-1: 0.2, more preferably 1: 0.1, and more preferably 1: 0.005-0.05. If the amount of the inventive cationic polymer less than 0.001 wt.% Based on the amount of fine inorganic pigment particles, the aggregation of fine inorganic pigment particles can not be avoided. If it is more than 0.2% by weight, can not aggregation of fine inorganic pigment particles avoided or a thick coating solution is obtained, which is unsuitable for coating.

The invention cationic polymer can be obtained by radical (co) polymerization of a Monomer containing a cationic group with a monomer, the copolymerizable in the presence of a chain transfer agent with an alkyl group having a total of 4-36 carbon atoms and a Mercapto. examples for the chain transfer agent include 1-butylmercaptan, 1-pentylmercaptan, 1-hexylmercaptan, 1-heptylmercaptan, 1-octylmercaptan, 1-nonylmercaptan, 1-decylmercaptan, 1-undecylmercaptan, 1-dodecylmercaptan, 1-tridecylmercaptan, 1-tetradecylmercaptan, 1-pentadecylmercaptan, 1-hexadecylmercaptan, 1-heptadecylmercaptan, 1-octadecylmercaptan, 1-nonadecylmercaptan, 1-eicosylmercaptan, 1-docosylmercaptan, 1-hexacosylmercaptan, 1-triacontylmercaptan, 1-hexatriacontylmercaptan, sec-butylmercaptan, isobutylmercaptan, tert-butylmercaptan, neopentylmercaptan, 2-methyl-1-butylmercaptan, 3-methyl-1-butylmercaptan, 2-ethyl-1-butylmercaptan, 3,3-dimethyl-1-butylmercaptan, 2-methyl-1-pentylmercaptan, 3-methyl-1-pentylmercaptan, 4-methyl-1-pentylmercaptan, 2-propyl-1-pentylmercaptan, 2,4,4-trimethyl-1-pentylmercaptan, 2-ethyl-1-hexyl, 3,5,5-trimethyl-1-hexylmercaptan, 3,7-dimethyl-1-octylmercaptan, 2-pentylmercaptan, 3-pentylmercaptan, 2-hexylmercaptan, 3-hexylmercaptan, 2-heptylmercaptan, 2-octylmercaptan, 3-octylmercaptan, 2-nonylmercaptan, 2-decylmercaptan, 4-decylmercaptan, 2-undecylmercaptan, 2-dodecylmercaptan, 2-tetradecylmercaptan, 2-hexadecylmercaptan, 3-methyl-2-butylmercaptan, 3,3-dimethyl-2-butylmercaptan, 3-methyl-2-pentylmercaptan, 4-methyl-2-pentylmercaptan, 2-methyl-3-pentylmercaptan, 4,4-dimethyl-2-pentylmercaptan, 4,4-dimethyl-2-methyl-2-pentyl mercaptan, 2,2-dimethyl-3-pentyl mercaptan, 2,4-dimethyl-3-pentylmercaptan, 5-methyl-2-hexylmercaptan, 2-methyl-3-hexylmercaptan, 6-methyl-2-heptyl mercaptan, 4-methyl-3-heptylmercaptan, 2,6-dimethyl-4-heptylmercaptan, tert-amylmercaptan, 2,3-dimethyl-2-butyl, 2-methyl-2-pentylmercaptan, 3-methyl-3-pentylmercaptan, 3-ethyl-3-pentylmercaptan, 2,3-dimethyl-3-pentylmercaptan, 3-ethyl-2,2-dimethyl-3-pentylmercaptan, 2-methyl-2-hexylmercaptan, 3,7-dimethyl-3-octylmercaptan, cyclohexylmercaptan, phenylmercaptan, Naphthylmercaptan, tolylmercaptan, bentylmercaptan, phenethylmercaptan, 1-octylthioglycolate, 1-decylthioglycolate, 1-octadecylthioglycolate, 2-ethylhexyl thioglycolate, isooctyl thioglycolate, 1-octylmercaptopropionate, 1-decylmercaptopropionate, 1-octadecylmercaptopropionate, 2-ethylhexylmercaptopropionate, Isooctylmercaptopropionate, octyloxyethylmercaptan, octyloxyethylthioglycolate, Octyloxyethylmercaptopropionate and the following compounds (B) to (D).

specific examples for the cationic polymers (cationic polymers 1 to 45) are given below, however, the invention is not limited thereto.

Cationic Polymer 1

Cationic Polymer 2

Cationic Polymer 3

Cationic Polymer 4

Cationic polymer 5

Cationic polymer 6

Cationic polymer 7

Cationic polymer 8

Cationic polymer 9

Cationic polymer 10

Cationic polymer 11

Cationic Polymer 12

Cationic polymer 13

Cationic polymer 14

Cationic polymer 15

Cationic polymer 16

Cationic polymer 17

Cationic polymer 18

Cationic polymer 19

Cationic polymer 20

Cationic polymer 21

Cationic polymer 22

Cationic polymer 23

Cationic polymer 24

Cationic polymer 25

Cationic polymer 26

Cationic Polymer 27

Cationic Polymer 28

Cationic polymer 29

Cationic Polymer 30

Cationic Polymer 31

Cationic Polymer 32

Cationic polymer 33

Cationic Polymer 34

Cationic Polymer 35

Cationic Polymer 36

Cationic polymer 37

Cationic Polymer 38

Cationic Polymer 39

Cationic Polymer 40

Cationic polymer 41

Cationic Polymer 42

Cationic Polymer 43

Cationic polymer 44

Cationic polymer 45

Fine inorganic pigment particle

Examples for the fine inorganic pigment particles close fine silica particles, colloidal silica, titanium dioxide, barium sulfate, calcium silicate, zeolite, Kaolinite, halloysite, mica, talc, calcium carbonate, magnesium carbonate, Calcium sulfate, boehmite and quasi-boehmite. Among these compounds For example, fine silica particles and quasi-boehmite are particularly preferred.

The fine silica particles have a high ink absorbing ability and retention efficiency because of their particularly large specific surface area. Further, since they have a low refractive index, they can impart transparency to the image-receiving layer by dispersing them in an appropriate particle size, whereby a high color density and a good color-forming property can be achieved. The transparency of the image-receiving layer is not only in applications where transparency is required, such as OHP, but also in a recording sheet such as Fo, in view of achieving high color density and good color-forming property Glossy paper, of importance.

The average primary particle size of fine inorganic pigment particles is preferably 20 nm or less, more preferably 10 nm, and more preferably 3-10 nm.

There the fine silica particles have a silanol group on their surface and the particles easily by hydrogen bonding of the silanol group can cling to each other, can they provide a structure with a high void fraction when their average primary particle size 10 nm or less. Thereby For example, the ink receiving property of the sheet can be effectively improved. Furthermore, can the fine silica particles generally based on the manufacturing process in particles produced by the wet process, and Particles made by a dry process are classified become.

When Wet method is widely used a method of manufacturing of a silica hydrate to produce an active silica acid decomposition of a silicate, suitable polymerization of the active Silicas, aggregation and precipitation of the resulting product. In contrast, as Dry method, a method widely used under high temperature gas phase hydrolysis a silicon halide (flame hydrolysis method) and a method to produce a silica anhydride by heating, reduction and gasification of silica sand and coke by Bogenwärmung in an electric furnace and acidification by Air (arc method) applied.

Since the silica hydrates and silica anhydrides obtained by these methods are different in the concentration of the surface silanol groups, the presence or absence of holes or the like, they have different properties. In particular, silica anhydride is preferable because it can easily form a three-dimensional high void structure. Although the reason for this is not known, the silanol group concentration on the surface of the fine particles in the case of silica hydrate is 5-8 groups / nm ² , so that the fine silica particles can easily densely aggregate. In contrast, due to the fact that the silanol group concentration on the surface of the 2-3 group / nm ² fine particles is low, silica anhydride does not provide dense flocculation. As a result, silica anhydride is believed to provide a high void structure.

Therefore, it is preferable in the invention to use a silica (fine silica particles) having 2-3 silanol groups per nm ^{2 of} the surface of the fine particles.

When fine inorganic pigment particles is a quasi-boehmite as well prefers. Quasi-boehmite is a colloidal crystal agglomerate of boehmite (whose composition is AlOOH) and preferably contains a binder. In terms of its pore properties is the average pore radius preferably 1-10 nm, more preferably 3-10 nm, and the pore volume is preferably 0.5-1.0 ml / g.

The coating amount of the quasi-boehmite is preferably 5-30 g / m ² . If the coating amount is less than 5 g / m ² , the ink absorbency is lowered or the gloss may be degraded by the influence of the roughness of the support. If the coating amount is more than 30 g / m ² , not only wasteful manner quasi-boehmite is consumed but also the strength of the quasi-boehmite can be reduced.

Regarding the The composition of the quasi-boehmite coating solution may preferably be one to be used, the 5-50 Parts by weight of a binder per 100 parts by weight of the quasi-boehmite solid component used, the total solids content being 5-30% by weight. is. The solvent of coating solution is preferably in terms of handling properties Water-based. As a binder can preferably an organic binder, a starch or a modified product thereof, a polyvinyl alcohol or a modified one Product thereof, a polymer compound such as SBR latex, NBR latex, a carboxymethyl cellulose, a hydroxymethyl cellulose and a Polyvinylpyrrolidone and the like can be used.

water-soluble Resin:

It is preferable that the image-receiving layer is prepared by coating a dispersion containing fine inorganic pigment particles and a water-soluble resin on a support. Examples of the water-soluble resin include a resin having a hydroxyl group as a hydrophilic structural unit, such as a polyvinyl alcohol (PVA), a cation-modified polyvinyl alcohol, an anion-modified polyvinyl alcohol, a silanol-modified polyvinyl alcohol, a polyvinyl acetal, a cellulose resin [such as a methylcellulose (MC), an ethylcellulose (EC), a hydroxyethylcellulose (HEC) and a carboxymethylcellulose (CMC)], chitins, chitosans and starch; a resin having an ether bond, such as a polyethylene oxide (PEO), a polypropylene oxide (PPO), a polyethylene glycol (PEG) and a polyvinyl ether (PVE); a resin having an amide group or an amide bond, such as a polyacrylamide (PAAM) and a polyvinylpyrrolidone (PVP).

Furthermore can be considered water soluble Resin of one having a carboxyl group used as the dissociating group such as a polyacrylic acid salt, a maleic acid resin, an alginic acid salt and gelatins.

Under In the above examples, polyvinyl alcohols are particularly preferred.

Of the Content of the water-soluble Resin is preferably 9-40 Wt.%, Based on the total weight of the solid components of image-receiving layer, more preferably 16-33% by weight.

If the content of the water-soluble Resin is less than 9% by weight, the film strength is reduced so that at the time of drying easily cracking occurs. If it is more than 40%, the Samples are easily clogged by the resin, so the ink absorbency may be reduced by reducing the void fraction.

Either the fine inorganic pigment particles as well as the water-soluble resin, the main ones The image-receiving layer can be constructed as a single material or provided as a mixture of multiple materials.

Furthermore is in terms of transparency the nature of the combination with of the fine inorganic pigment particles used in the resin of Importance. When silica anhydride is used, it is the water-soluble resin preferably a polyvinyl alcohol (PVA), more preferably a PVA with a saponification degree of 70-99%, and more preferred a PVA with a degree of saponification of 70-90%.

Of the PVA has a hydroxyl group in the structural unit. The hydroxyl group and the silanol group on the surface of the fine silica particles form a hydrogen bond, thereby forming a three-dimensional Lattice structure with one of the secondary particles of the fine silica particles constructed chain structures is facilitated. It is believed, that with the formation of the three-dimensional lattice structure a Image-receiving layer with a porous structure with high void content can be generated.

at The ink jet recording absorbs a porous image-receiving Layer obtained as described above, an ink quickly through the capillary phenomenon, thus forming points with good roundness without ink bleeding become.

Salary ratio of fine inorganic pigment particles to water-soluble resin:

The content ratio of the fine inorganic pigment particles (preferably fine silica particles or Quasi-boehmite; (i)) to water-soluble Resin (p) [PB ratio (i: p), Mass of all fine inorganic pigment particles with respect to 1 Part by weight of the water-soluble Resin] has a significant influence on the layer structure the image-receiving layer. That means, with a big PB ratio the void ratio, the pore volume and the surface (per unit mass) large.

More accurate is the PB ratio (i: p) preferably 1.5: 1-10: 1. If the PB ratio is more than 10: 1, i. if the PB ratio is too large, the Film strength, so that at the time of drying easily a Cracking occurs. In contrast, then, if less than 1.5: 1, i.e. if the PB ratio too small, pores are easily clogged by the resin, so that the ink absorbency can be lowered by reducing the void fraction.

If an ink jet recording sheet by a propulsion system in an inkjet printer is passed, may be applied to the recording sheet exerted a tension and therefore the image-receiving layer should have a sufficient Have film strength. When the recording material cut into sheets is, should the image-receiving layer further in terms of the prevention of cracking, peeling of the image-receiving layer or the like, have sufficient film strength.

In In this case, the PB ratio preferably 5: 1 or less. With regard to ensuring a high speed of ink absorbency in the inkjet printer it is preferably 2: 1 or more.

For example, when a coating solution obtained by dispersing fine inorganic pigment particles having an average primary particle size of 20 nm or less and a water-soluble resin in an aqueous solution in a PB ratio of 2: 1-5: 1 is coated on a support and dried is formed, a three-dimensional lattice structure with a chain unit composed of secondary particles of the inorganic fine pigment particles, so that easily a translucent porous film having an average pore size of 30 nm or less, a void content of 50-80%, a pore volume of 0.5 mm / g or more and a specific surface area of 100 m ² / g or more.

Crosslinking agent:

It It is preferable that an image-receiving layer of an ink jet recording sheet of the present invention Preferably, a coating layer (porous layer) which is a crosslinking agent, the for crosslinking a water-soluble Resin is capable, in addition to fine inorganic pigment particles and the water-soluble Contains resin and by the crosslinking reaction of the crosslinking agent with the water-soluble Hardened resin becomes.

The Crosslinking agent is preferably simultaneously with the lamination the coating solution (first Coating Solution) for the production of the porous image receiving layer is added to the sheet or is second coating solution added to the sheet before the coating layer, which has been coated by the first coating solution is formed, showing a decreasing rate of drying. By doing so, the generation of cracking during the Drying the coating layer can be efficiently prevented. That is, the crosslinker solution penetrates into the coating layer and rapidly with the water-soluble resin in the coating layer implemented, which makes the water-soluble Resin while adding it with the coating solution coating or before the coating layer has a decreasing rate of drying shows gelled (hardened becomes). Thereby, the film strength of the coating layer immediately dramatically improved. The crosslinking agent may be included in the first and / or second coating solution or may become a coating solution other than the first or second coating solution be added.

The crosslinking agent capable of crosslinking the water-soluble resin may be optionally selected depending on the water-soluble resin used in the image-receiving layer. In particular, it is a boron compound due to its rapid cross-linking reaction. Examples of the boron compound include borax, a boric acid, a borate [such as orthoborate, InBO ₃ , ScBO ₃ , YBO ₃ , LaBO ₃ , Mg ₃ (BO ₃ ) ₂ and Co ₃ (BO ₃ ) ₂ ], a diborate [e.g. for example, Mg ₂ B ₂ O ₅ and Co ₂ B ₂ O ₅ ], a metaborate [such as LiBO ₂ , Ca (BO ₂ ) ₂ , NaBO ₂ and KBO ₂ ], a tetraborate (such as Na ₂ B ₄ O ₇ · 10H ₂ O] and a pentaborate [such as KB ₅ O ₈ .4H ₂ O, Ca ₂ B ₄ O ₁₁ .7H ₂ O and CsB ₅ O ₅ ] In addition, a glyoxal, a melamine formaldehyde (such as Methylol melamine and an alkylated methylol melamine), a methylol urea, a resole resin, a polyisocyanate, an epoxy resin or the like can be used as the crosslinking agent, in particular, borax, a boric acid and a borate are preferable because of their rapid crosslinking reaction, moreover, they are preferably used in combination with a polyvinyl alcohol used as a water-soluble resin.

When a gelatin is used as the water-soluble resin, the following crosslinking agents known as gelatin film hardeners can be used. More specifically, examples include an aldehyde compound such as formaldehyde, glyoxal and glutaraldehyde; a ketone compound such as diacetyl and cyclopentanedione; an active halogen compound such as bis (2-chloroethylurea) -2-hydroxy-4,6-dichloro-1,3,5-triazine and a sodium salt of 2,4-dichloro-6-S-triazine; an active vinyl compound such as divinylsulfonic acid, 1,3-vinylsulfonyl-2-propanol, N, N'-ethylenebis (vinylsulfonylacetamide) and 1,3,5-triacryloylhexahydro-S-triazine; an N-methylol compound such as dimethylolurea and methyloldimethylhydantoin; an isocyanate compound such as 1,6-hexamethylene diisocyanate; an aziridine compound disclosed in U.S. Patents 3,017,280 and 2,983,611; a carboxyimide compound disclosed in U.S. Patent No. 3,100,704; an epoxy compound such as glycerol triglycidyl ether; an ethyleneimino compound such as 1,6-hexamethylene-N, N'-bisethyleneurea; a halogenated carboxyaldehyde compound such as mucochloric acid and mucophenoxychloric acid; a dioxane compound such as 2,3-dihydroxydioxane; and Chromalum, a potassium alum, a zirconium sul fat and a chromium acetate.

The Crosslinking agents can used singly or in a combination of two or more species. The crosslinker solution can be prepared by dissolving a crosslinking agent in water and / or an organic solvent. The concentration the crosslinking agent in the crosslinking agent solution is preferably 0.05-10% by weight, based on the weight of the crosslinking agent solution, more preferably 0.1-7 wt.%.

The solvent the crosslinker solution is preferably water, and further, a mixture may be used the water and a water-miscible solvent contains.

It Optionally, any organic solvent may be used as long as it can dissolve the crosslinker. Close examples for this an alcohol such as methanol, ethanol, isopropyl alcohol and glycerin; a ketone such as acetone and methyl ethyl ketone; an ester such as methyl acetate and ethyl acetate; one aromatic solvent, such as toluene; an ether such as tetrahydrofuran; and a halogenated hydrocarbon solvent, such as dichloromethane.

Organic mordant:

It is according to the invention to further improve the water resistance of the formed image and the resistance Bleeding over time is preferred in the image-receiving Layer an organic pickling agent (hereinafter also simplified to be included as "pickling agent").

The Mordant is preferably a cationic polymer (cationic Mordant). The mordant added to the image-receiving layer can with a liquid Ink having an anionic dye as the colorant, the colorant stabilize and water resistance and the resistance across from Improve bleeding over time.

If the mordant directly to the first coating solution for Generation of the image-receiving layer is added, can between the mordant and the fine inorganic pigment particles with anionic charge may aggregate, however, when in Form of another solution as the first coating solution is added, such aggregation does not occur. Therefore, will according to the invention Mordant to the second coating solution containing no inorganic fine Contains pigment particles added and used in it.

The cationic mordant is preferably a polymer mordant a primary to tertiary Amino group or a quaternary Ammonium salt as a cationic group, but it can also be a cationic non-polymeric mordant be used.

The polymeric mordant is preferably a homopolymer of a monomer (Mordant monomer) having a primary to tertiary amino group or a salt thereof or a quaternary ammonium salt, or a Copolymer or a condensation polymer of the mordant with another monomer (hereinafter referred to as "non-mordant monomer"). Furthermore can these polymer mordants in the form of either a water-soluble Polymer or latex particles which can be dispersed in water become.

Examples of the monomer (mordant monomer) include trimethyl-p-vinylbenzylammonium chloride, trimethyl-m-vinylbenzylammonium chloride, triethyl-p-vinylbenzylammonium chloride, triethyl-m-vinylbenzylammonium chloride, N, N-dimethyl-N-ethyl-Np-vinylbenzylammonium chloride, N, N- Diethyl-N-methyl-Np-vinylbenzylammonium chloride, N, N-dimethyl-Nn-propyl-Np-vinylbenzylammonium chloride, N, N-dimethyl-Nn-octyl-Np-vinylbenzylammonium chloride, N, N-dimethyl-N-benzyl-Np- vinylbenzylammonium chloride, N, N-diethyl-N-benzyl-Np-vinylbenzylammonium chloride, N, N-dimethyl-N- (4-methyl) benzyl-Np-vinylbenzylammonium chloride, N, N-dimethyl-N-phenyl-Np-vinylbenzylammonium chloride, trimethyl p-vinylbenzylammonium bromide, trimethyl-m-vinylbenzylammonium bromide, trimethyl-p-vinylbenzylammonium sulfonate, trimethyl-m-vinylbenzylammonium sulfonate, trimethyl-p-vinylbenzylammonium acetate, trimethyl-m-vinylbenzylammonium acetate, N, N-triethyl-N-2- (4- vinylphenyl) ethylammonium chloride, N, N, N-triethyl-N-2- (3-vinylphenyl) ethylammonium chloride, N , N-diethyl-N-methyl-N-2- (4-vinylphenyl) ethylammonium chloride, N, N-diethyl-N-methyl-N-2- (4-vinylphenyl) ethylammonium acetate, N, N-dimethylaminoethyl (meth) acrylate , N, N-diethylaminoethyl (meth) acrylate, N, N-dimethylaminopropyl (meth) acrylate, N, N-diethylaminopropyl (meth) acrylate; a quater nes product of N, N-dimethylaminoethyl (meth) acrylamide, N, N-diethylaminoethyl (meth) acrylamide, N, N-dimethylaminopropyl (meth) acrylamide and N, N-diethylaminopropyl (meth) acrylamide due to methyl chloride, ethyl chloride, methyl bromide, Ethyl bromide, methyl iodide or ethyl iodide; and a sulfonate, an alkylsulfonate, an acetate and an alkylcarboxylate whose anion is substituted.

Especially can Monomethyldiallylammonium chloride, trimethyl-2- (methacryloyloxy) ethylammonium chloride, Triethyl-2- (methacryloyloxy) ethylammonium chloride, Trimethyl-2- (acryloyloxy) ethylammonium chloride, Triethyl-2- (acryloyloxy) ethylammonium chloride, Trimethyl-3- (methacryloyloxy) propylammonium chloride, triethyl-3- (methacryloyloxy) propylammonium chloride, Trimethyl-2- (methacryloylamino) ethylammonium chloride, triethyl 2- (methacryloylamino) ethylammonium chloride, Trimethyl-2- (acryloylamino) ethylammonium chloride, triethyl 2- (acryloylamino) ethylammonium chloride, Trimethyl 3- (methacryloylamino) propylammonium chloride, triethyl 3- (methacryloylamino) propylammonium chloride, Trimethyl-3- (acryloylamino) propylammonium chloride, triethyl-3- (acryloylamino) propylammonium chloride, N, N-dimethyl-N-ethyl-2- (methacryloyloxy) ethylammonium chloride, N, N-diethyl-N-methyl-2- (methacryloyloxy) ethylammonium chloride, N, N-dimethyl-N-ethyl-3- (acryloylamino) propylammonium chloride, Trimethyl-2- (methacryloyloxy) ethylammonium bromide, Trimethyl-3- (acryloylamino) propylammonium bromide, Trimethyl-2- (methacryloyloxy) ethylammonium, Trimethyl-3- (acryloylamino) propylammonium acetate and the like can be used as a mordanting monomer.

Furthermore can N-vinylimidazole, N-vinyl-2-methylimidazole and the like can be used as a copolymerizable monomer.

The Non-mordant monomer denotes a monomer that is not basic or cationic region, such as a primary to tertiary amino group or a salt thereof and a quaternary ammonium salt and the like and not with a dye in an inkjet ink interacts or has a substantially minor interaction with it shows.

Examples for the Non-mordant monomers include an alkyl (meth) acrylate; a cycloalkyl (meth) acrylate, such as cyclohexyl (meth) acrylate; an aryl (meth) acrylate, such as phenyl (meth) acrylate; an aralkyl ester, such as benzyl (meth) acrylate; aromatic vinyl compounds, such as styrene, vinyl toluene and α-methylstyrene; Vinyl ester, like for example, vinyl acetate, vinyl propionate and vinyl barbate; allyl ester, such as allyl acetate; a halogen-containing monomer, such as for example, vinylidene chloride and vinyl chloride; a vinyl cyanide, such as (meth) acrylonitrile; and olefins, such as Ethylene and propylene, a.

The Alkyl (meth) acrylate preferably has 1-18 carbon atoms in the Alkyl group. Close examples for this Methyl (meth) acrylate, ethyl (meth) acrylate, propyl (meth) acrylate, isopropyl (meth) acrylate, n-butyl (meth) acrylate, isobutyl (meth) acrylate, t-butyl (meth) acrylate, Hexyl (meth) acrylate, octyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, Lauryl (meth) acrylate and stearyl (meth) acrylate.

Under these compounds are methyl acrylate, ethyl acrylate, methyl methacrylate, Ethyl methacrylate and hydroxyethyl methacrylate are preferred.

The Non-mordant monomers can used singly or in a combination of two or more species become.

Furthermore preferred examples of the polymer mordant include polydiallyldimethylammonium chloride, Polymethacryloyloxyethyl-β-hydroxyethyldimethylammonium, a polyethyleneimine, a polyallylamine and a modified product thereof, a polyallylamine hydrochloride, a polyamide-polyamine resin, a cationic starch, a condensed product of dicyandiamide formalin, a polymer of dimethyl 2-hydroxypropyl ammonium salt, a polyamidine and a polyvinylamine. A polyallylamine and a derivative thereof is particularly preferred.

The Polyallylamine derivative is a product obtained by addition of acrylonitrile, chloromethylstyrene, TEMPO, epoxyhexane, sorbic acid or the like to a polyallylamine in an amount of 2-50 mol%. Preferably, it is an adduct wherein 5-10 mol% of acrylonitrile or Chloromethylstyrene are added to a polyallylamine. Especially is an adduct with respect to avoiding ozone discoloration from polyallylamine and 5-10 mol% acrylonitrile is preferred.

The weight average molecular weight of the mordant is preferably 5,000-200,000. When the molecular weight is 5,000-200,000, the water resistance and the resistance to be improved over bleeding over time.

Other components:

The The image-receiving layer may include the following components as needed lock in.

To the Purpose of the restriction of the colorant degradation can various types of decolorizing agents, such as a UV absorber, an antioxidant and a singlet oxygen quencher.

Examples for the UV absorbers include a cinnamic acid derivative, a benzophenone derivative, a benzotriazole phenol derivative and the like. Close examples for this Butyl-α-cyano-phenyl cinnamate, o-benzotriazole phenol, o-Benzotriazole p-chlorophenol, o-benzotriazole-2,4-di-t-butylphenol and o-benzotriazole-2,4-di-t-octylphenol one. As the UV absorber, a hindered phenol compound be used. More specifically, a phenol derivative wherein at least one, selected from the 2-position and the 6-position, with a branched alkyl group is substituted, preferred.

Furthermore can also a benzotriazole UV absorber, a salicylic acid UV absorber, a cyanoacrylate UV absorber, an oxalic acid anilide UV absorber and the like can be used. These are disclosed, for example in JP-A Nos. 47-10437, 58-111942, 58-212844, 59-19945, 59-46646, 59-109055, 63-53544, JP-B Nos. 36-10466, 42-26187, 48-30492, 48-31255, 48-41572, 48-54965, 50-10726, U.S. Patents 2,719,086, 3,707,375, 3,754,919, 4,220,711 and the like.

When UV absorber can also use a fluorescent brightener become. Close examples for this a coumarin brightener. More specifically, this compound is disclosed in JP-B Nos. 45-4699, 54-5324 and the like.

Examples for the Antioxidants include those described in EP Nos. 223,739, 309 401, 309 402, 310 551, 310 552, 459 416, DE-PS 34 35 443, JP-A Nos. 54-48535, 60-107384, 60-107383, 60-125470, 60-125471, 60-125472, 60-287485, 60-287486, 60-287487, 60-287488, 61-160287, 61-185483, 61-211079, 62-146678, 62-146680, 62-146679, 62-282885, 62-262047, 63-051174, 63-89877, 63-88380, 66-88381, 63-113536, 63-163351, 63-203372, 63-224989, 63-251282, 63-267594, 63-182484, 1-239282, 2-262654, 2-71262, 3-121449, 4-291685, 4-291684, 5-61166, 5-119449, 5-188687, 5-188686, 5-110490, 5-1108437, 5-170361, JP-8 Nos. 48-43295, 48-33212 and U.S. Patents 4,814,262 and 4,980,275.

More accurate close concrete examples of this 6-ethoxy-1-phenyl-2,2,4-trimethyl-1,2-dihydroquinoline, 6-ethoxy-1-octyl-2,2,4-trimethyl-1,2-dihydroquinoline, 6-ethoxy-1-phenyl 2,2,4-trimethyl-1,2,3,4-tetrahydroquinoline, 6-ethoxy-1-octyl-2,2,4-trimethyl-1,2,3,4-tetrahydroquinoline, Nickel cyclohexanoate, 2,2-bis (4-hydroxyphenyl) propane, 1,1-bis (4-hydroxyphenyl) -2-ethylhexane, 2-methyl-4-methoxydiphenylamine and 1-methyl-2-phenylindole one.

The Entfärbungsverhinderungsmittel can used singly or as a combination of two or more species become. The decolorization preventing agents can as water-soluble Product, be used as a dispersion or emulsion, or they can contained in microcapsules.

The Amount of decolorization agent is preferably 0.01-10 % By weight, based on the coating solution for the image-receiving layer.

Further can for the purpose of improving the dispersing properties of the fine inorganic pigment particles, an inorganic salt and as a pH adjusting agent an acid, a base or the like may be included.

Further can for the purpose of limitation the friction charging or Abziehaufladung the surface fine Trapped metal oxide particles with electron conductivity, and for the purpose of reducing the friction characteristics of the surface a matting agent may be included.

Process for the preparation the image-receiving layer:

Next, a method for producing the image-receiving layer will be described. It is preferable that an image-receiving layer of the present invention is prepared by coating an ers A coating solution (image receiving layer coating solution) containing at least fine inorganic pigment particles and a cationic polymer of the present invention, and applying a second coating solution containing at least a crosslinking agent and an organic mordant to the coating solution (1) simultaneously with the lamination of the first Coating solution, (2) during drying of the coating layer formed by the first coating solution, and before the coating layer shows a decreasing rate of drying, or (3) after drying of the coating layer, whereby the coating layer is cured.

As mentioned above, can the water resistance the image-receiving layer can be improved by adding the Mordant to the second coating solution, together with the crosslinking agent, and Applying the second coating solution simultaneously with the lamination. That is, when the mordant is added to the first coating solution can be between the mordant, which is cationic, and the fine inorganic pigment particles having an anionic charge on the surface cause an aggregation. However, by a method is applied, after which the second coating solution containing the mordant, and the first coating solution independently can be made from each other and applied separately the selection range of the mordant be extended without that takes into account the aggregation of fine inorganic pigment particles must become.

According to the invention the first coating solution for one image-receiving layer containing at least fine organic pigment particles (such as fine silica particles), a cationic according to the invention Polymer and a water-soluble Resin (such as PVA), for example, prepared as follows become.

she can be prepared by adding fine silica particles in water (for example, in an amount of 10-20% by weight), offsetting the resulting Mixture with a solution, the one according to the invention contains cationic polymer (For example, by adding a 30% methanol solution, see that the amount of the inventive cationic polymer 0.005-0.05 Weight%, based on the amount of produced by a gas phase process Silicas), dispersing for 20 minutes (preferably 10-30 minutes) under high-speed revolution conditions of 10,000 rpm (preferably 5,000-20,000 Rpm) using a high speed colloid mill from Rotational and wet type (such as Kurea Mix, manufactured M Technique Co., Ltd.), adding an aqueous polyvinyl alcohol solution (e.g. Add PVA so that its amount is about one third of the mass corresponding to that of the silica) and dispersing under the above mentioned revolution conditions. The obtained first coating solution is a homogeneous sol, and a porous sol Image-receiving layer with a three-dimensional lattice structure can be prepared by layering and drying it on a carrier according to the following coating method.

One Surfactant, a pH adjuster, an antistatic agent or the like may further be added as needed to the first coating solution become.

The first coating solution can be coated on the carrier by a known coating method such as with an extrusion die coater, an air knife coater, a blade coater, a bar coater, a knife coater, a squeeze coater, a reverse roll coater and a Wire bar.

Of the Expression "before the coating layer has a decreasing rate of drying shows "as above mentioned, generally designates the period immediately after Apply the first coating solution for a few minutes Termination of the application of the first coating solution. During this Time, the coating layer shows a constant rate of drying, i.e. the effect that the solvent content decreases in proportion to time in the coating layer. The Time at which the coating layer has a constant rate of drying is published in Chemical Engineering Handbook (pp. 707-712) from Maruzen Co., Ltd. on October 25, 1980).

As mentioned above, becomes the coating layer after coating the first coating layer dried until the coating layer has a decreasing rate of drying shows. Drying is generally carried out at 50-180 ° C for 0.5-10 minutes (preferably 0.5-5 Minutes). Although the drying time of course from the coating amount depends the above range is suitable.

Examples of methods for applying a coating solution, which is an organic solvent (second coating solution) before the coating layer shows a decreasing rate of drying, (1) a method for coating a second coating solution on the coating layer, (2) a method of spraying the second coating solution, and (3) a method of immersing the carrier with the Coating layer in the second coating solution.

The Process for coating the second coating solution (the The above-mentioned method (1)) can be prepared by a known coating method carried out be such as with a curtain coater, a extrusion die, an air knife coater, a blade coater, a bar coater, a knife coater, a squeegee coater, a reverse roll coater and a wire rod coater. However, it is preferred to have a method without direct contact of the coater with the already trained Apply coating layer, such as with an extrusion die coater, a curtain coater or a wire rod coater. Furthermore can when coating two or more types of coating solution simultaneously to superimposed Layers are layered.

The simultaneous coating (generation of superimposed layers) can be done after a coating process in which, for example, an extrusion die coater and a curtain coater is used. The resulting Coating layer is dried after simultaneous coating. In this case, drying is usually carried out by heating the Coating layer at 40-150 ° C for 0.5-10 minutes carried out, preferably by heating at 40-100 ° C for 0.5-5 minutes.

For example it is in the case that borax and a boric acid than those in the second coating solution Crosslinking agent is used, preferably, the superimposed Layers for 5-20 minutes to heat at 60-100 ° C.

Furthermore in the case that the second coating solution after drying the coating solution is applied, the drying of the coating layer by heating at 40-150 ° C for 0.5-10 minutes, preferably by heating at 40-100 ° C for 0.5-5 minutes, carried out.

The Crosslinking agent may be any of the first and second Coating solutions added and on the carrier can be applied, or can be applied by manufacturing a solution which contains it separately from the first and second coating solutions, and Apply the solution at any time during of the coating step.

Furthermore can in any stage of coating water, an organic solvent or a mixture thereof as a solvent be used. examples for that for the coating used organic solvents include alcohols, such as methanol, ethanol, n-propanol, isopropanol and Methoxypropanol, ketones, such as acetone and methyl ethyl ketone, Tetrahydrofuran, acetonitrile, ethyl acetate and toluene.

The Surface smoothness, the Gloss level, transparency and coating film strength of image-receiving layer can can be improved by the image-receiving layer thus obtained subjected to a calendering process, wherein the image-receiving Layer under heating and pressurizing using, for example, a supercalender or a gloss calender passed through a nip roll becomes. However, since the calendering process reduces the Void fraction (i.e., the ink absorbency can be reduced), should it be carried out under conditions which hardly reduce the void fraction. In the calendering process the roll temperature is preferably 30-150 ° C, more preferably 40-100 ° C.

Furthermore is the linear pressure between the rolls in the calendering process preferably 50-400 kg / cm, more preferably 100-200 kg / cm.

Since the absorbing ability for absorbing all the liquid droplets should be provided in the case of an ink-jet recording sheet, the thickness of the image-receiving layer should be determined depending on the void content of the layer. For example, in the case of an ink amount of 8 nl / mm ² and a void content of 60%, the thickness of the layer should be about 15 μm or more.

Under consideration This point is the thickness of the image-receiving layer in the case the inkjet recording preferably 10-50 microns.

Further is the pore size (medium size) the image-receiving layer is preferably 0.005-0.030 μm, more preferably 0.01-0.025 μm.

Of the Void content and mean pore size can be measured with a mercury porosimeter (Product name: Pure Sizer 9320-PC2, manufactured by Shimadzu Corporation).

Further For example, it is preferred that the image-receiving layer be excellent Has transparency.

When Measure for this is the turbidity value the image-receiving layer formed on the transparent film support is, preferably 30% or less, more preferably 20 or less.

Of the haze value can be measured with a turbidimeter (HGM-2DP; manufactured by Suga Test Instruments Co., Ltd.).

Of the carrier can either be a transparent carrier that is a transparent one Material includes, such as a plastic, or a opaque carrier, which comprises an opaque material, such as a paper. To take advantage of the transparency of the image-receiving layer It prefers a transparent support or a high gloss opaque carrier to use.

The Material for the transparent carrier is preferably a transparent material with durability across from Radiant heat when used in an overhead projector (OHP) or backlight display) is used. Examples include a polyester such as polyethylene terephthalate (PET); a polysulfone, a polyphenylene oxide, a polyimide, a polycarbonate and a polyamide. Among these compounds, a polyester is preferable, and polyethylene terephthalate is further preferred.

The Thickness of the transparent support is not particularly limited however, it is preferable in terms of ease of handling 50-200 μm.

Of the opaque high gloss carrier is preferably one whose gloss on the surface with the image-receiving layer is 40% or more. The shine is a value which is obtained by the method disclosed in JIS P-8142 is (75 ° mirror surface gloss test method for paper and cardboard).

Especially close examples of this Glossy paper carrier such as art paper, coated paper, cast coated Paper and baryta paper as a carrier for silver salt photography used, as well as opaque glossy films containing a white pigment or the like contained in a plastic film, such as Polyesters, including polyethylene terephthalate (PET), cellulose polyesters, including nitrocellulose, cellulose acetate and cellulose acetate butyrate, a polysulfone, a polyphenylene oxide, a polyimide, a polycarbonate and a polyamide, and these opaque glossy films can one Oberflächenkalandrierungsbehandlung be subject; and a carrier with a coating layer polyolefin containing or not containing a white pigment the surface the above, various types of paper carriers, the transparent straps or the white pigment containing high gloss films.

Further can also preferably foamed Polyester films containing a white pigment can be used (such as foamed PET with cavities, which is prepared to contain fine polyolefin particles, and is aligned).

The Thickness of the opaque carrier is not particularly limited however, it is preferable in terms of ease of handling 50-300 μm.

Further can the carriers a corona discharge process, a glow discharge process, a flame process, a UV irradiation process or the like.

When next that will be in the paper carrier Used base paper described in detail. The base paper is mainly made of wood pulp and can be made as needed from a synthetic pulp, such as a polypropylene, or a synthetic fiber, such as a nylon and a polyester, in addition to the wood pulp. The wood pulp can be any one selected from LBKP, LBSP, NBKP, NBSP, LDP, NDP, LUKP, and NUKP, and it is preferred to use a large amount of LBKP, NBSP, LBSP, NDP and LDP, the have a large amount of short fibers.

Of the However, the proportion of LBSP and / or LDP is preferably 10-70% by weight.

Preferably may be a chemical pulp (a sulfate pulp and a sulfite pulp) be used with a few impurities, and further, too a pulp having a degree of whiteness improved by a bleaching process suitable.

The Base paper may include a sizing agent as needed, such as for example, a higher one fatty acid and an alkyl ketene dimer, a white pigment, such as calcium carbonate, Talc and titanium oxide, a chemical for increasing paper strength, such as a starch, a polyacrylamide and a polyvinyl alcohol, a fluorescent brightener, a water retention agent, such as polyethylene glycols, a dispersant and a plasticizer, such as quaternary ammonium.

Of the Grinding degree of for papermaking pulp, measured according to the CSF standard, is preferably 200-500 ml. Above Beyond the fiber length after hitting the sum in wt.% Of the residue component to 24 mesh and the residue component to 42 mesh as specified in JIS P-8207, preferably 30-70%. Of the % By weight of the residue component 4 mesh is preferably 20% by weight or less.

The weight of the base paper is preferably 30-250 g, more preferably 50-200 g. The thickness of the base paper is preferably 40-250 μm. The base paper may be subjected to a calendering process during or after papermaking, thereby providing it with greater smoothness. The density of the base paper is generally 0.7-1.2 g / m ² (JIS P-8118).

Further the stiffness of the base paper is preferably 20-200 g under the conditions specified in JIS P-8143.

On the base paper surface can be a surface sizing agent be applied. The surface sizing agent may be the same as the sizing agents mentioned above be added to the base paper.

Of the pH of the base paper is preferably 5-9, measured by the hot water extraction method according to JIS P-8113.

The Polyethylene for covering the front surface and the back side surface of the base paper is mainly a low density polyethylene (LDPE) and / or a high density polyethylene (HDPE). Together with LDPE and / or HDPE can be an LLDPE, a polypropylene or the like can be used.

The Polyethylene layer on the side with the image-receiving layer contains Preferably, a rutile or anatase type of titanium oxide for improvement the opacity and whiteness, similar like a photographic print paper. The titanium oxide content is preferably 3-20 % By weight, based on the polyethylene, more preferably 4-13% by weight.

The polyethylene-coated paper is used as glossy paper or it can also be used one that has a frosted or silky surface which is obtained by a stamping process at the time of Melt extrusion and coating of the polyethylene on the base paper surface, similar to in a conventional photographic printing paper.

As previously described, the printing density of the image according to the invention without Deterioration of other ink properties can be improved. Since the image-receiving layer, the fine inorganic pigment particles contains a three-dimensional lattice structure with a void fraction of 50-80 %, may further have good ink absorbency be provided, whereby a high-resolution image is generated, and bleeding over time under conditions of high temperature and high humidity, and further the excellent ink receptivity, the picture with excellent light fastness and water resistance can be ensured.

EXAMPLES

Hereinafter, the present invention will be explained with reference to examples, but the invention is not limited to the examples. "Parts" and "%" in the examples indicate "parts by weight" and "% by weight" unless otherwise specified. A number following the expression "WM" indicates the "Ge weight average molecular weight ", and" degree of polymerization "denotes the" weight average degree of polymerization ".

SYNTHESIS EXAMPLES OF A CATIONIC INVENTION OF THE INVENTION POLYMER:

SYNTHESIS EXAMPLE 1

A 30% methanol solution of a cationic polymer 1 (cationic polymer of the general formula (1), which is a repeating unit of the general formula (2) was obtained by dissolving 30 parts of N- [2- (methacryloyloxy) ethyl] -N, N, N-trimethylammonium chloride and 1.6 parts of 2-ethylhexyl-3-mercaptopropionate in 70 parts of methanol, Heat the resulting mixture at 65 ° C in a stream of nitrogen, Addition of 0.16 part V-50 (polymerization initiator, prepared from Wako Pure Chemical Industries, Ltd.) to the mixture, and others Heat for 4 hours.

SYNTHESIS EXAMPLE 2

A 30% methanol solution a cationic polymer 2 (cationic polymer of the general formula (1), which is a repeating unit of the general formula (2) was used in the same manner as in Synthesis Example 1, except that the addition amount of 2-ethylhexyl-3-mercaptopropionate changed from 1.6 parts to 3.3 parts has been.

SYNTHESIS EXAMPLE 3

A 30% methanol solution of a cationic polymer 3 (cationic polymer of the general formula (1), which is a repeating unit of the general formula (2) was used in the same manner as in Synthesis Example 1, except that the 30 parts of N- [2- (methacryloyloxy) ethyl] -N, N, N-trimethylammonium chloride were replaced by 30 parts of N- [3- (methacryloylamino) -2-hydroxypropyl] -N, N, N-trimethylammonium chloride.

SYNTHESIS EXAMPLE 4

A 30% methanol solution a cationic polymer 4 (cationic polymer of the general formula (1), which is a repeating unit of the general formula (2) was used in the same manner as in Synthesis Example 1, except that the 30 parts of N- [2- (methacryloyloxy) ethyl] -N, N, N-trimethylammonium chloride were replaced by 30 parts of N- [2- (methacryloyloxy) ethyl] -N-benzyl-N, N-dimethylammonium chloride.

SYNTHESIS EXAMPLE 5

A 30% methanol solution a cationic polymer 5 (cationic polymer of the general formula (1), which is a repeating unit of the general formula (2) was used in the same manner as in Synthesis Example 1, except that the 30 parts of N- [2- (methacryloyloxy) ethyl] -N, N, N-trimethylammonium chloride exchanged were replaced by 20 parts of N- [2- (methacryloyloxy) ethyl] -N, N, N-trimethylammonium chloride and 10 parts of methyl acrylate.

SYNTHESIS EXAMPLE 6

A 30% methanol solution a cationic polymer 6 (cationic polymer of the general formula (1), which is a repeating unit of the general formula (2) was used in the same manner as in Synthesis Example 1, except that the 1.6 parts of 2-ethylhexyl-3-mercaptopropionate were replaced by 1.5 parts of n-dodecanethiol.

SYNTHESIS EXAMPLE 7

A 30% methanol solution a cationic polymer 7 (cationic polymer of the general formula (1), which is a repeating unit of the general formula (2) was used in the same manner as in Synthesis Example 1, except that the 1.6 parts of 2-ethylhexyl-3-mercaptopropionate were replaced by 2.1 parts of n-Octadecanthiol.

SYNTHESIS EXAMPLE 8

A 30% methanol solution a cationic polymer 8 (cationic polymer of the general formula (1), which is a repeating unit of the general formula (2) was used in the same manner as in Synthesis Example 1, except that the 1.6 parts of 2-ethylhexyl-3-mercaptopropionate were replaced by 0.84 parts of cyclohexylmercaptan.

SYNTHESIS EXAMPLE 9

A 30% methanol solution a cationic polymer 9 (cationic polymer of the general formula (1), which is a repeating unit of the general formula (2) was used in the same manner as in Synthesis Example 1, except that the 1.6 parts of 2-ethylhexyl-3-mercaptopropionate were replaced by 2.5 parts of octadecylthioglycolate.

Comparative Synthesis Example 1

A 30% methanol solution a cationic polymer 10 (cationic polymer for comparison) was obtained in the same manner as in Synthesis Example 1, except that the 1.6 parts of 2-ethylhexyl-3-mercaptopropionate are not were added.

Comparative Synthesis Example 2

A 30% methanol solution a cationic polymer 11 (cationic polymer for comparison) was obtained in the same manner as in Synthesis Example 1, except that the 1.6 parts of 2-ethylhexyl-3-mercaptopropionate exchanged were replaced by 0.45 parts of ethanethiol.

PREPARATION OF AN INK RECORDING SHEET:

EXAMPLE 1

Production of the carrier:

An art paper of 186 g / m ² as base paper (OK Kondo, manufactured by Oji Paper Co., Ltd.) was subjected to a corona discharge process and coated with a high-density polyethylene using a melt extruder so that its thickness was 19 μm, thereby forming a resin layer with a matte surface (hereinafter, the resin layer surface is referred to as the "back surface"). Subsequently, the resin layer was subjected to a corona discharge treatment, and then a dispersion in which alumina (Aluminasol 100, manufactured by Nissan Chemical Industries, Ltd.) and silica (Snow Tex O, manufactured by Nissan Chemical Industries, Ltd.) in water in a mass ratio of 1: 2 was coated on the resin layer as an antistatic agent so that the dry amount was 0.2 g / m ² .

Further became the other after applying a corona discharge process surface (Felt surface) of the base paper without the resin layer, a thermoplastic high gloss resin layer on this surface (hereinafter, the glossy surface is referred to as "front side") by a low density polyethylene with a melt flow index (MFI) of 3.8, the 10% anatase type titanium dioxide, a small amount Ultramarine and 0.01% (based on polyethylene) of a fluorescent brightener contained, melted with a melt extruder and extruded was so that its thickness is 24 microns amounted to. In this way, a carrier was obtained. On the front side of the carrier was before coating a coating solution for an image-receiving layer a corona discharge treatment was performed.

Preparation of the coating solution for an image-receiving Layer (first coating solution):

A coating solution A for an image-receiving layer (first coating solution) having the following composition was prepared by mixing (1) fine silica particles prepared by a gas phase method with (2) ion-exchanged water, adding (3) the 30% Methanol solution of the cationic polymer 1 to the resulting mixture, two-fold processing of the resulting mixture at a pressure of 500 kg / m ² using a Nanomizer LA31 (manufactured by Nanomizer Corp.), stirring for 60 minutes, adding (4) an 8% aqueous polyvinyl alcohol solution with stirring, and further adding (5) a 10% aqueous solution of Emargen 109P and (6) diethylene glycol monobutyl ether to the resulting mixture. The weight ratio of the fine silica particles and the water-soluble resin (PB ratio / (1) :( 4)) was 4.5: 1.

Preparation of the ink receptive sheet:

The image receiving layer coating solution A obtained as described above was coated on the front side of the support using an extrusion die coater (coating step) so that the coating amount became 200 ml (m ²⁾ , and the obtained layer was baked at 80 ° C. with a hot air dryer ( During this period, the coating layer showed a constant drying speed of the coating layer Immediately thereafter, the support was immersed in a crosslinking agent solution A having the following composition (second coating solution) for 30 seconds That is, the second coating solution was adhered to the coating layer, the amount being 20 g / m ² (step of applying the crosslinking agent solution), and the support was dried at 80 ° C for 10 minutes (drying step) The ink-receiving sheet (1) obtained was provided with an ink-receiving layer having a dry film thickness of 32 μm.

EVALUATION PROCEDURES:

(1) Evaluation of the coating solution for image-receiving Layer (1-1):

300 g of the coating solution A for one Image-receiving layer was placed in a 500 ml container. After 10 minutes Dipping the container in a constant temperature bath of 30 ° C, the viscosity at 60 Rpm using a B-type viscometer (manufactured by Tokimec Inc.) and to evaluate the state of dispersion the coating solution A for one image-receiving layer according to used the following standard. The results are in table 1 indicated.

Default:

• AA:

  a good state of dispersion, the for the coating is suitable, with a viscosity of less than 100 mPa.s;

  BB:

  a dispersion state with little difficulty in coating, with a viscosity of 100 to less than 1,000 mPa · s;

  CC:

  a dispersion state, with which a coating was not possible, with a viscosity of 1,000 mPa · s or more.

(1-2) Average particle size:

The mean volume standard particle size D50 of the fine particles in the coating solution A for one Image-receiving layer was measured using a light scattering diffraction type particle distribution meter (LA910, manufactured by Horiba, Ltd.). The value was as average particle size used and rated according to the following standard. The results are given in Table 1. The measurement became a refractive index of 1.10 entered as a parameter.

Default:

• AA:

  less than 0.2 μm

  BB:

  0.2 to less than 5.0 μm

  CC:

  5.0 μm and more

(1-3) Coarse particles:

This Point was determined by the proportion of the particles of 5 μm or more, as measured in the above item (2) with respect to all the particles, evaluated. The results are shown in Table 1.

Default:

• AA:

  less than 2

  BB:

  2 to less than 10

  CC:

  10% or more

(2) Evaluation of the ink-jet recording sheet:

(2-1) gloss:

Of the 60 ° gloss the image-receiving layer surface of a recording sheet before printing, a digital variable gloss meter (UGV-50DP, manufactured by Suga Test Instruments Co., Ltd.) and measured evaluated according to the following standard. The results are in table 2 indicated.

Default:

• AA:

  40 or more

  BB:

  30 to less than 40

  CC:

  less than 30

(2-2) Ink absorption speed:

frames in Y (yellow), M (purple), C (blue-green), K (black), B (blue), G (green) and R (red) were put on the ink jet recording sheet Using an inkjet printer (PM-900C, manufactured by Seiko Epson Corporation). Immediately thereafter became paper pressed directly against the pictures, and it was evaluated according to the following standard, whether the ink was on transfer the paper was or not. The results are shown in Table 2.

Default:

• AA:

  Transfer the ink to the Paper was not observed

  BB:

  partial transmission the ink on the paper has been observed, but to an extent that for the Practical use was without significant problems

  CC:

  Transfer of ink to paper was observed to a significant extent.

(2-3) Cracking:

The Presence or absence of cracks on the surface of the ink-receiving sheet, and the size thereof were visually observed and evaluated by the following standard. The results are shown in Table 2.

Default:

• AA:

  was on the surface no cracking observed

  BB:

  it was cracking with a length from 1-2 mm observed

  CC:

  it was cracking with a length of 3 mm or more.

(2-4) Water resistance:

The same print patterns were made using the same printer as above under (2-2) described on an ink jet recording sheet. After 3 hours Leaving the leaves were left she for 1 minute immersed in water. The extent of elution of the ink in The water was visually observed and determined by the following standards rated. The results are shown in Table 2.

Default:

• AA:

  it was not Elution of the dye observed

  BB:

  it became a partial Elution of the dye observed, whereby the color density deteriorates has been

  CC:

  the dye became largely complete eluted into the water.

(2-5) Resistance to bleeding over time:

One grid-like linear pattern (line width 0.28 mm) was under Using the same printer as described above (2-2) with a purple ink and a black ink next to each other printed on an inkjet recording paper, and the visual density thereof was prepared with an X Rite 310TR (U.S. from X-Rite). Further, the printed sheet was left to stand for 3 hours in a constant temperature and humidity vessel at 40 ° C and 90 ° C % relative humidity for Kept for 1 day. Then the visual density was measured again, and the density difference (ΔOD) was calculated and evaluated according to the following standard. One smaller value of density difference (ΔOD) indicates durability across from the production of bleeding. The results are shown in Table 2.

Default:

• AA:

  less than 0.36

  BB:

  0.36 to less than 0.5

  CC:

  0.5 or more

(2-6) light resistance:

frames in Y (yellow), M (purple), C (teal) and K (black) were added Using the same printer as described above (2-2) on an ink-jet recording sheet imprinted, and the visual density of each color was determined by X Rite 310TR (manufactured by X-Rite). Subsequently was the lamp of a xenon weathering device Ci65A (manufactured by Atlas Corp.) for 3.8 hours below 25 ° C and 32% relative humidity, and the printed images were through a film to cut off the W radiation with a wavelength of 365 nm or less exposed from the light. Then the Lamp for 1 hour off while the pictures at 20 ° C and 91% relative humidity. This cycle was over 11 days repeated. Then the visual density of each color was measured again, and the residual ratio (Density change ratio before and after the test) as the degree of decolorization of each Color was calculated and evaluated according to the following standards. The results are shown in Table 2.

Default:

• AA:

  without significant discoloration

  BB:

  slight discoloration

  CC:

  clear discoloration

(2-7) image density (print density)

AA:

2,0 oder mehr

BB:

1,8 bis weniger als 2,0

CC:

weniger als 1,8

A black frame was printed on an ink jet recording sheet using the same printer as in the above-described item (2-2). After standing for 3 hours, the reflection density of the printed surface was measured by a Macbeth reflection densitometer and evaluated according to the following standard. The results are shown in Table 2.

AA:

2.0 or more

BB:

1.8 to less than 2.0

CC:

less than 1.8

EXAMPLES 2 TO 9, COMPARATIVE EXAMPLES 1 to 5

Coating solutions B to N for An image-receiving layer was prepared in the same manner as in Example 1 except that the cationic polymer 1 of the coating solution A for one image-receiving layer and the addition amount thereof were changed to the cationic polymers and the addition levels as in Table 1, and there were inventive ink jet recording sheets and Comparative ink jet recording sheets made and evaluated. The results are shown in Table 2. In Comparative Examples 1, 2, 4 and 5 resulted in the high viscosity of the image-receiving coating solutions Layer to the fact that a layering on the carrier was impossible.

TABLE 1

Based from Table 1 it was found that the coating solutions for the image-receiving layer, those of the invention cationic polymers were added, an aggregation of fine Silica particles prepared by a gas phase process, can resist and provide a dispersion with a good flowability.

in the In contrast, the coating solutions showed J, K, M and N for an image-receiving layer, in which a cationic polymer was used, which at his End had no group selected from an alkyl group with a total of 4-36 Carbon atoms, an aryl group and an aralkyl group, or no cationic polymer (aggregation inhibitor) included (Comparative Examples 1, 2, 4 and 5) a poor result the evaluation of the viscosity, the average particle size and the coarse particles, and because of their viscosity it was impossible she on the carrier top up. About that In addition, the coating solutions L and M were image-receptive Layer in which no inventive cationic polymer used was required (Comparative Examples 3 and 4), a large amount of the cationic polymer.

Out From the results shown in Table 2, it was found that the invention Inkjet recording sheets, in those of the invention cationic polymers to the coating solutions for the image-receiving layer were added, and contain the inorganic pigment particles, in terms of gloss, ink absorption rate, cracking, water resistance, the resistance across from Bleeding over time, light resistance and print density excellent are.

in the In contrast, as in Comparative Example 3, this was not a polymer according to the invention included, over time, a bleeding caused, and furthermore, the light resistance was low. Further, in Comparative Examples 1, 2, 4 and 5, the viscosity the coating solutions for the Image-receiving layer for producing an ink-jet recording sheet too high and therefore these were not evaluated.

Claims (15)

Ink jet recording sheet comprising a support and an image-receiving layer, the inorganic fine pigment particles and a cationic polymer having a group at its end, the selected is of an alkyl group having a total of 4 to 36 carbon atoms, an aryl group and an aralkyl group, wherein the image-accepting Layer is produced by coating a dispersion containing the fine inorganic pigment particles, the cationic polymer and a water-soluble Resin contains, on the carrier, and the image-receiving layer contains a crosslinking agent, the for crosslinking the water-soluble Resin is capable. An ink-jet recording sheet according to claim 1, wherein a dispersion in which the fine inorganic pigment particles in the presence of the cationic polymer having at its end a Group, selected from an alkyl group having a total of 4 to 36 carbon atoms, an aryl group and an aralkyl group are dispersed, for the Image receiving layer is used. An ink-jet recording sheet according to claim 1, wherein the cationic polymer is represented by the following general formula (1):

wherein X is a single bond or a divalent linking group, R is a straight, branched or cyclic alkyl group having a total of 4 to 36 carbon atoms, an aryl group or an aralkyl group, A is at least one kind of repeating units having a cation, B is at least one kind of itself repeating unit which is copolymerizable with A, m and n each represent the molar fraction of component A and component B, and 0.2 ≤ m ≤ 1.0, 0 ≤ n ≤ 0.8 and m + n = 1, 0th An ink-jet recording sheet according to claim 3, wherein R in the general formula (1) is selected from an unbranched, branched or cyclic alkyl group having a total of 8 to 18 carbon atoms, an aryl group or an aralkyl group. An ink jet recording sheet according to claim 3 or 4, wherein the repeating unit A in the general formula (1) is selected from the following groups (I) to (IV): (I) a repeating unit of the following general formula (2) :

wherein R ^{1 is} hydrogen or an alkyl group having 1 to 4 carbon atoms, R ² , R ³ and R ⁴ each independently represent a hydrogen atom or an alkyl group having 1 to 18 carbon atoms which may have a substituent or which may be bonded together to form a saturated or unsaturated one May ring, represent an aryl group or an aralkyl group, Z is -O- or -NH-, Y ^{2 is} a divalent linking group having a total of 1 to 18 carbon atoms which may contain a hetero atom, and X ^{- is} an anion; (II) a repeating unit of the following general formula (3):

wherein R ⁵ is a hydrogen atom or a methyl group and R ^2, R ^3, R ⁴ and X ^- are as defined in the general formula (2); (III) A repeating unit of the following general formula (4) or (5):

wherein R, R ³ and X ^{2 -} are as defined in the general formula (2); (IV) a repeating unit of the following general formula (6) or (7)

wherein n is 0 or 1, and R ^2, R ^3, R ⁴ and X ^- are as defined in the general formula (2). Ink jet recording sheet according to at least one of the claims 1 to 5, wherein the number average molecular weight of the cationic polymer 1,000 to 20,000. Ink jet recording sheet according to at least one of the claims 1 to 6, wherein the mass ratio (x: y) of the fine inorganic pigment particles (x) to cationic Polymer (y) 1: 0.001 to 1: 0.2. Ink jet recording sheet according to at least one of the claims 1 to 7, wherein the fine inorganic pigment particles are fine silica particles with an average primary particle size of 20 nm or less or a quasi-boehmite with an average pore radius of 1 to 10 nm. Ink jet recording sheet according to at least one of the claims 1 to 8, wherein the water-soluble Resin is polyvinyl alcohol or a derivative thereof. Ink jet recording sheet according to at least one of the claims 1 to 8, wherein the crosslinking agent is a boron compound. Ink jet recording sheet according to at least one of the claims 1 to 10, wherein the image-receiving layer is an organic mordant contains. An ink-jet recording sheet according to claim 11, wherein the organic mordant is a polyallylamine min or a derivative thereof. Ink jet recording sheet according to at least one of the claims 1 to 12, wherein the image-receiving layer is a three-dimensional Mesh structure with a void fraction of 50 to 80%, and that mass ratio (i: p) of the fine inorganic pigment particles (i) to the water-soluble Resin (p) is 1.5: 1 to 10: 1. Ink jet recording sheet according to at least one of the claims 11 to 13, wherein the image-receiving layer is obtainable by coating a first coating solution, the at least the fine inorganic pigment particles and the contains cationic polymer, on the support surface, and Applying a second coating solution containing at least the organic Contains pickling agent, on the coating layer (1) simultaneously with the coating, (2) during drying the coating layer by the above Coating is made, and before the coating layer shows a decreasing rate of drying, or (3) after drying the coating layer, and by curing and drying the coating layer. An ink-jet recording sheet according to claim 14, wherein the image-receiving layer is obtainable by application of the crosslinking agent which is at least one of the first and second coating solutions is added, or by applying a coating solution, the containing the crosslinking agent separate from the first and second coating solutions.