JP2005271212A - Support for recording material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a support for a recording material suitable as various recording materials such as photographic printing paper, electrophotographic image receiving paper, thermal recording paper, ink jet recording paper and the like and excellent in flatness and water resistance. <P>SOLUTION: The support for the recording material is constituted by providing a water-resistant resin coating layer at least on one side of raw paper. A coating layer containing a hydrophilic binder is provided between the raw paper and the water-resistant resin coating layer. The hydrophilic binder is crosslinked. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a recording material support, and more particularly to a recording material support excellent in water resistance suitable for various recording materials such as photographic printing paper, electrophotographic image receiving paper, thermal recording paper, and ink jet recording paper.

Conventionally, as a support used for recording materials such as silver halide photographic printing paper, ink jet recording paper, and thermal transfer recording image receiving sheet, a resin-coated support whose base paper surface is coated with a resin capable of forming a film is well known. ing. Recording materials such as silver halide photographic printing paper, ink jet recording paper, and thermal transfer recording image receiving sheet are required to have high surface smoothness (hereinafter also referred to as “flatness”) and glossiness. Resin-coated supports are also required to have high surface smoothness and gloss.
In addition, the support used for the recording material is required to have excellent water resistance, in particular, when it is used for photographic printing paper, it is difficult to be peeled off from a developing solution and a fixing solution at the time of development and fixing. Is done.

As a support that satisfies the above requirements, a synthetic resin-coated sheet coated with a pigment having a specific particle size on the surface of a base paper has been proposed, but its water resistance is insufficient, surface smoothness, and glossiness. Was not satisfactory (for example, see Patent Document 1).
In addition, a synthetic resin-coated sheet in which a specific amount of filler is added to a pulp slurry and a base paper obtained by making a paper is coated with a synthetic resin has been proposed, but further improvements in surface smoothness and gloss are desired (for example, (See Patent Document 2).
Furthermore, a support for image material using a coated paper having a specific glossiness and a specific surface roughness has been proposed. Although the surface smoothness is excellent, further improvement in water resistance is desired. (For example, refer to Patent Document 3).
On the other hand, a synthetic resin-coated sheet in which a specific amount or less of clay is applied to a base paper has been proposed. However, although the surface smoothness is excellent, further improvement in water resistance is desired (for example, see Patent Document 4). .)
JP 2001-334750 A JP-A-10-104790 JP 2001-301098 A JP 11-338105 A

  The object of the present invention is to solve the above-mentioned problems of the prior art, and is suitable for various recording materials such as photographic printing paper, electrophotographic image receiving paper, thermal recording paper, and ink jet recording paper, and has excellent flatness and water resistance. It is an object of the present invention to provide a recording material support.

The object has been achieved by the following means. That is,
<1> A support for a recording material having a water-resistant resin coating layer on at least one surface of a base paper, having a coating layer containing a hydrophilic binder between the base paper and the water-proof coating layer, and A support for recording material, wherein the hydrophilic binder is crosslinked.
<2> The recording material support according to <1>, wherein the hydrophilic binder contains one or more selected from polyvinyl alcohol and gelatin.

<3> The recording material support according to <2>, wherein the polyvinyl alcohol is acetoacetyl-modified polyvinyl alcohol.
<4> The support for a recording material according to any one of <1> to <3>, wherein the coating layer further contains a water-soluble fluorescent brightening agent.

<5> The support for a recording material according to any one of <1> to <4>, wherein the coating layer further contains an inorganic pigment.
<6> The above <1> to <1>, wherein the water resistant resin coating layer is composed of one or more selected from polyethylene and polypropylene, and the water resistant resin coating layer is produced by a melt extrusion laminating method. <5> The recording material support according to any one of <5>.

<7> A recording material support according to any one of <1> to <6>, wherein the recording material support is for a silver halide photographic light-sensitive material.

  The present invention is suitable for various recording materials such as photographic printing paper, electrophotographic image receiving paper, heat-sensitive recording paper, and ink jet recording paper, and can provide a recording material support excellent in flatness and water resistance.

The recording material support of the present invention is a recording material support having a water-resistant resin coating layer on at least one surface of a base paper, and includes a hydrophilic binder between the base paper and the water-resistant coating layer. It has a coat layer, and the hydrophilic binder is crosslinked.
By providing a coating layer satisfying these conditions on the base paper, it is excellent in flatness and water resistance. For example, the water-resistant resin film layer against the developer during development is difficult to peel off (hereinafter also referred to as “developer resistance strength”). .) A support is obtained. Here, the flatness is caused by the unevenness of the paper surface due to the aggregate of paper fibers, generally called the formation, and also due to the unevenness of each fiber, for example, a smoothness meter, a surface roughness meter. Further, it means the degree of unevenness on the surface of the recording material support that can be measured by a gloss meter, image clarity evaluation device, and human visual evaluation.
Hereinafter, the support for recording material of the present invention will be described.

  Examples of the pulp that can be used for the base paper of the recording material support of the present invention include mechanical pulps such as crushed wood pulp (GP), refiner ground pulp (RGP), and thermomechanical pulp (TMP) made from conifers and hardwoods. (MP), chemical pulp (CP) such as sulfite pulp (SP) and kraft pulp (KP), chemi-ground pulp (CGP), semi-chemical pulp (SCP), deinked pulp (DIP) made from waste paper, etc. Can be mentioned.

A beater or refiner can be used to beat the pulp.
In the present invention, calcium pulp can be added as a filler to the pulp slurry obtained after beating the pulp, and if necessary, a dry paper strength enhancer, a wet paper strength enhancer, a sizing agent, and a fixing agent. , PH adjusting agents, other additives, and the like can be added.

  In the present invention, the addition of calcium carbonate to the pulp slurry is preferable in terms of improving the surface smoothness and glossiness of the recording material support.

In the present invention, in addition to calcium carbonate as the filler, for example, clay, kaolin, white clay, talc, titanium oxide, diatomaceous earth, barium sulfate, aluminum hydroxide, magnesium hydroxide and the like can be mentioned.
The filler can be added to the pulp slurry together with the calcium carbonate.

Examples of the dry paper strength enhancer include cationized starch, cationized polyacrylamide, anionized polyacrylamide, and carboxy-modified polyvinyl alcohol.
Examples of the sizing agent include rosin derivatives such as fatty acid salts, rosin and maleated rosin, paraffin wax, alkyl ketene dimer, alkenyl succinic anhydride (ASA) and the like.
Examples of the wet paper strength enhancer include polyamine polyamide epichlorohydrin, melamine resin, urea resin, and epoxidized polyamide resin.
Examples of the fixing agent include polyvalent metal salts such as aluminum sulfate and aluminum chloride, and cationic polymers such as cationized starch.
Examples of the pH adjuster include caustic soda and sodium carbonate.

Examples of the other additives include an antifoaming agent, a dye, a slime control agent, and a fluorescent brightening agent. Moreover, you may add a softening agent as needed.
The softening agent is described in, for example, New Handbook for Paper Processing (edited by Paper Medicine Time), pages 554 to 555 (issued in 1980), and those having a molecular weight of 200 or more are particularly preferable. This softening agent is an amine salt or a quaternary ammonium salt having a hydrophobic group having 10 or more carbon atoms and self-fixing with cellulose. Specific examples of the softening agent include a reaction product of a maleic anhydride copolymer and a polyalkylene polyamine, a reaction product of a higher fatty acid and a polyalkylene polyamine, a reaction product of a urethane alcohol and an alkylating agent, Examples thereof include quaternary ammonium salts of higher fatty acids. Particularly preferred are reaction products of maleic anhydride copolymers and polyalkylene polyamines, and reaction products of urethane alcohols and alkylating agents.
The above drugs may be used alone or in combination of two or more. Moreover, as addition amount to the slurry of these said pulps, 0.1-1.0 mass% is preferable.

  As a means for paper making the slurry of the pulp, for example, a hand paper machine, a long paper machine, a round paper machine, a twin wire machine, a combination machine and the like can be used.

In the present invention, a coating liquid containing a crosslinked hydrophilic binder between the base paper made by these means and dried and the water-resistant resin coating layer (hereinafter also referred to as “coating layer coating liquid”). ), And the hydrophilic binder is a crosslinked support for recording material.
By forming the coating layer, the water resistance strength of the recording material support of the present invention is improved.

  Examples of the hydrophilic binder in the coating layer coating solution include polyvinyl alcohol (PVA) [PVA, acetoacetyl-modified PVA, cation-modified PVA, anion-modified PVA, silanol-modified PVA], a cellulose resin [methyl cellulose (MC), Ethyl cellulose (EC), hydroxyethyl cellulose (HEC), carboxymethyl cellulose (CMC), hydroxypropyl cellulose (HPC), hydroxyethyl methyl cellulose (HEMC), hydroxypropyl methyl cellulose (HPMC), etc.], chitins, chitosans, starch, ether bond Resin [polyethylene oxide (PEO), polypropylene oxide (PPO), polyethylene glycol (PEG), polyvinyl ether (PVE), etc.], Resins having a rubermoyl group [polyacrylamide (PAAM), polyvinylpyrrolidone (PVP), polyacrylic acid hydrazide, etc.], resins having a carboxyl group as a dissociative group [polyacrylic acid salt, maleic acid resin, alginate, gelatin] Etc.

Among the above, PVAs and gelatins are preferable from the viewpoints of cost, ease of crosslinking, and liquid stability, and acetoacetyl-modified PVA and gelatin, particularly acetoacetyl-modified PVA are preferable.
These may be used singly or in combination of two or more, but at least the hydrophilic binder is preferably one or more selected from PVAs and gelatins. From the viewpoint of obtaining strength, the content is preferably 20% by mass or more, and more preferably 50% by mass or more, based on the solid content mass of the hydrophilic binder.

  The content of the hydrophilic binder is preferably 5 to 100% by mass and more preferably 20 to 80% by mass from the viewpoint of obtaining an appropriate liquid viscosity and film strength with respect to the total solid mass. The hydrophilic binder contained in the coating layer enhances the interlayer adhesion, and has effects such as the function as a protective colloid of the pigment, the coloring property of the fluorescent brightening agent, and the oxygen barrier property.

  The PVA as the hydrophilic binder preferably has a saponification degree of 70 to 99 mol%, and more preferably 80 to 99 mol%, from the viewpoint of water resistance.

  When the saponification degree is in the range of 70 to 99 mol%, the crystallinity of the polymer is improved, so that the water resistance tends to be improved.

  Moreover, as a polymerization degree of PVA as a hydrophilic binder, it is preferable that a polymerization degree is 300-5000, Furthermore, it is preferable that it is 500-5000 from a viewpoint of film | membrane intensity | strength and water resistance, and especially 500 It is preferably ~ 3500.

  When the polymerization degree is in the range of 300 to 3500, handleability, film strength and water resistance are improved, and the adhesiveness tends to be improved.

  Further, the hydrophilic binder needs to be cross-linked in the coat layer, and by being cross-linked, the effect of further developing high film strength and water resistance is exhibited.

Any crosslinking agent that can crosslink the hydrophilic binder can be used as long as it can crosslink the hydrophilic binder. Examples of the crosslinking agent include boric acid and boron compounds. Examples of the boron compound include borax and borates (for example, orthoborate, InBO ₃ , ScBO ₃ , YBO ₃ , LaBO ₃ , Mg ₃ (BO ₃ ) ₂ , Co ₃ (BO ₃ ) ₂ , diborate (eg, Mg ₂ B ₂ O ₅ , Co ₂ B ₂ O ₅ ), metaborate (eg, LiBO ₂ , Ca (BO ₂ ) ₂ , NaBO ₂ ) , KBO _2), tetraborate _{(eg, Na 2 B 4 O 7 ·} 10H 2 O), five borate _{(e.g., KB 5 O 8 · 4H 2} O, Ca 2 B 6 O 11 · 7H 2 O, CsB ₅ O ₅ ), etc. Aldehyde compounds such as formaldehyde, glyoxal and glutaraldehyde; Ketone compounds such as diacetyl and cyclopentanedione; Bis (2-chloroethylurea) -2-hydroxy-4, 6-jiku Active halogen compounds such as loro-1,3,5-triazine, 2,4-dichloro-6-S-triazine sodium salt; divinylsulfonic acid, 1,3-vinylsulfonyl-2-propanol, N, N′- Active vinyl compounds such as ethylenebis (vinylsulfonylacetamide) and 1,3,5-triacryloyl-hexahydro-S-triazine; N-methylol compounds such as dimethylolurea and methyloldimethylhydantoin; melamine resins (for example, Methylol melamine, alkylated methylol melamine); epoxy resin;

Isocyanate compounds such as 1,6-hexamethylene diisocyanate; aziridine compounds described in US Pat. Nos. 3,017,280 and 2,983611; carboximide compounds described in US Pat. No. 3,100,704; glycerol triglycidyl Epoxy compounds such as ether; Ethyleneimino compounds such as 1,6-hexamethylene-N, N′-bisethyleneurea; Halogenated carboxaldehyde compounds such as mucochloric acid and mucophenoxycyclolic acid; 2,3-dihydroxy Dioxane compounds such as dioxane and 3-dihydroxy-6-methyl-1,4-dioxane; metal-containing compounds such as titanium lactate, aluminum sulfate, chromium alum, potash alum, zirconyl acetate, chromium acetate, tetraethylenepentamine Polyamine etc. Compounds, hydrazide compounds such as adipic acid dihydrazide, low molecular or polymer containing two or more oxazoline groups, triazine compounds such as 2,6-dichloro-4-hydroxy-triazine sodium alcoholate, etc. From the viewpoint of crosslinkability, dioxane compounds and triazine compounds are preferable. Specifically, 2,6-dichloro-4-hydroxy-triazine sodium alcoholate, 2,3-dihydroxy-6-methyl-1,4- Dioxane is preferred. These may be used alone or in combination of two or more.

These crosslinking agents can be produced by a known method and are not particularly limited. As long as the above conditions are satisfied, any of them can be used, and a commercially available crosslinking agent may be used.
By using these cross-linking agents, the mechanical strength and water resistance strength of the coating film can be improved, and the adhesive strength in Dry / Wet can be improved.

  As the addition amount of the cross-linking agent, it is used in an amount of 0.1% by mass to 20% by mass with respect to the mass of the hydrophilic binder as necessary. Among them, from the viewpoint of obtaining a sufficient cross-linking density, 1% by mass to 20 mass% is preferable, and 1 mass%-10 mass% are especially preferable.

  When the addition amount of the crosslinking agent is in the range of 1% by mass to 20% by mass, a sufficient crosslinking density can be obtained, and since it is a residual crosslinking agent, it can be suppressed, and the film strength and water resistance are improved. It is a tendency to become possible.

  The crosslinking agent may be added together with the water, the hydrophilic binder and other additives when preparing the coating layer coating solution, but is not particularly limited, and may be added by various methods as necessary. Can do.

The coating layer preferably contains a water-soluble fluorescent whitening agent.
Examples of the water-soluble fluorescent brightener include stilbene-based brighteners having a water-soluble group as described in, for example, US Pat. No. 2,933,390, Japanese Patent Publication No. 48-30495, and Japanese Patent Publication No. 55-135833. Among them, a white agent is mentioned, and among them, a compound that causes little bleeding out of the water-soluble fluorescent whitening agent from the coating layer is particularly preferable.
In particular, a water-soluble diaminostilbene compound is preferable, and it is even better if it has a sulfone group as the water-soluble group.
These may be used singly or in combination of two or more different types.

There is no restriction | limiting in particular as a manufacturing method of the said water-soluble fluorescent whitening agent, It can manufacture by a conventionally well-known method. In particular, water-soluble fluorescent whitening agents including 4,4′-diaminostilbene disulfonic acid derivatives are described in, for example, “Fluorescent whitening agent” (published in August, 1976) edited by Chemical Industry Association. It can be synthesized by ordinary methods.
In the present invention, a commercially available water-soluble fluorescent whitening agent can also be used.

  As a method for adding the water-soluble optical brightener used in the present invention, it may be added to the coat layer as an aqueous solution, or it is added to the coat layer together with a water-soluble polymer such as polyvinyl alcohol as the hydrophilic binder. Is used.

The content of these water-soluble fluorescent brighteners in the coating layer is preferably 0.02 to 0.10% by mass, and more preferably 0.04 to 0.08% by mass.
By setting the content in the above range, the effect of improving the whiteness of the background (fluorescence intensity) becomes remarkable, and bleeding out of the water-soluble fluorescent whitening agent is difficult to occur.

  The coat layer may contain a thickener, a surfactant, a bluing agent and the like together with a hydrophilic binder.

The coating amount of the coating layer coating solution on at least one surface of the base paper is preferably 0.5 g / m ² or more, and more preferably 1.0 g / m ² or more. By setting the coating amount of the coating layer coating liquid on at least one surface of the base paper within the above range, it becomes easy to obtain a support having excellent flatness.

  The coating apparatus used to apply the coating layer coating solution includes a roll coater, a gravure coater, a die coater, a curtain coater, a spray coater, a blade coater, a rod coater, an impregnation coater, a cast coater, an air knife coater, and a reverse coater. A coater, lip coater, kiss coater or the like is used.

The coat layer preferably contains an inorganic pigment.
Examples of the inorganic pigment include calcium carbonate, kaolin, calcined clay, satin white, titanium dioxide, aluminum hydroxide, silica, and plastic pigment. From the viewpoint of smoothness and gloss, among others, calcium carbonate, kaolin, and calcined Clay and titanium dioxide are preferred, and calcium carbonate is more preferred.
These may be used alone or in combination.
Further, when the pigment is composed of calcium carbonate and a pigment other than calcium carbonate, the proportion of calcium carbonate in the pigment is preferably 50% by mass or more, and more preferably 70% by mass or more.

As described above, the base paper coated with the coating layer coating liquid on at least one surface is subjected to a calendar process. Specifically, a machine calendar, a soft calendar, a super calendar, and a shoe calendar are used for the calendar process. As the metal roll and the elastic roll used for the calendering process, known ones used for the production of ordinary paper are used.
Through the calendar process, the base paper on which the coating layer used for the recording material support is finally adjusted to a thickness of 50 to 250 μm. In addition, as a density of this base paper, 0.8-1.3 g / m < ³ > is preferable and 1.0-1.2 g / m < ³ > is preferable.

In the recording material support of the present invention, the surface of the above-mentioned coating layer is further coated with a water-resistant resin to form a water-resistant resin coating layer.
Examples of the water-resistant resin include polyethylene, polypropylene, polybutene, polypentene and other homopolymers, copolymers composed of two or more α-olefins such as ethylene-butylene copolymers, and mixtures thereof. Polyethylene and polypropylene are particularly preferred from the viewpoints of melt extrusion coating properties and adhesion to the base paper.
Examples of the polyethylene resin include low density polyethylene, medium density polyethylene, high density polyethylene, linear low density polyethylene, copolymers of ethylene and α-olefin such as propylene, butylene, carboxy-modified polyethylene, and the like, and mixtures thereof. Is mentioned.
The density, melt flow rate (hereinafter also referred to as “MFR”), molecular weight, and molecular weight distribution of the polyethylene resin are not particularly limited, and any one can be used, but usually the density is 0.90 to 0.97 g. / M ³ range, MFR 0.1g / 10min to 50g / 10min, preferably MFR 0.3g / 10min to 40g / 10min can be used alone or in combination. .

  Various additives can be contained in the water-resistant resin. As the various additives, it is preferable to add titanium dioxide for the purpose of increasing the resolution of the image. As titanium dioxide, various titanium dioxide pigments are used such as sulfuric acid method, chlorine method, rutile type, anatase type, surface treatment with hydrous metal oxide, surface treatment with organic compound, etc. be able to.

  In addition, in the water-resistant resin, white pigments such as zinc oxide, talc and calcium carbonate are used as pigments, fatty acid amides such as stearic acid amide and arachidic acid amide are used as releasing agents, pigment dispersing agents and releasing agents. As an agent, fatty acid metal salts such as zinc stearate, calcium stearate, aluminum stearate, magnesium stearate, zinc palmitate, zinc myristate, calcium palmitate, and the like, hindered phenols described in JP-A-1-105245, Various antioxidants such as hindered amine, phosphorus and sulfur, blue pigments and dyes such as cobalt blue, ultramarine, ceria blue and phthalocyanine blue, magenta pigments such as cobalt violet, fast violet and manganese violet, Dye, Tokuhei 4-2 Quinacridone red pigments described in 75 JP, fluorescent whitening agents described in JP-A-2-254440, various additives such as an ultraviolet absorber can be incorporated in combination. These additives are preferably used in combination in the resin composition used in the practice of the present invention or as a separate resin masterbatch or compound.

In the present invention, the thickness of the water-resistant resin coating layer is suitably 4 μm to 100 μm, preferably 6 μm to 70 μm, particularly preferably 9 μm to 60 μm on the image forming side. Moreover, when providing a polyolefin resin coating layer on the opposite side so that it may mention later, generally the range of 4 micrometers-100 micrometers is suitable, Preferably it is the range of 6 micrometers-60 micrometers.
The resin of the resin film formed on the image forming side and the opposite side is preferably the same type.

  In the present invention, as a method of coating the water-resistant resin, a so-called melt-extrusion coating method (in which a water-resistant resin is cast and coated from a slit die onto a traveling base paper by using a melt extruder) Hereinafter, it is also preferable to coat by “melt extrusion lamination method”.

  The recording material support of the present invention described above is suitably used for various recording materials such as photographic printing paper (for example, for silver halide photographic light-sensitive materials), electrophotographic image receiving paper, heat-sensitive recording paper, and ink jet recording paper. However, the support for recording materials of the present invention can be particularly preferably used for photographic printing paper because it can sufficiently withstand processing with an alkali developing solution and fixing under acidic conditions.

  Examples of the present invention will be described below, but the present invention is not limited to these examples. In the following, “%” and “part” represent “% by mass” and “part by mass” unless otherwise specified.

<Example 1>
[Preparation of base paper]
As a pulp sample, wood pulp consisting of 100 parts by mass of LBKP was beaten to 300 ml of Canadian freeness with a double disc refiner (adjusted blade shape and clearance was adjusted as appropriate), 0.5 parts by mass of epoxidized behenamide, anion polyacrylamide 1 0.0 part by mass, 0.1 part by mass of polyamide polyamine epichlorohydrin and 0.5 part by mass of cationic polyacrylamide were added at an absolute dry weight ratio to pulp, and 15 parts by mass of calcium carbonate as a filler (content in pulp slurry) (Solid content: 12.8% by mass) was added, and paper was made using a long web paper machine to a basis weight of 150 g / m ² to obtain a base paper.

[Formation of coat layer]
On both surfaces of the obtained base paper, a coating solution composed of the following components was applied and dried in line at a solid content of 4 g / m ² to form coat layers on both sides of the base paper.

<Coating layer coating solution>
(1) Water 89.43 parts (2) Goosephimer Z-210 104.84 parts (acetoacetyl-modified polyvinyl alcohol, manufactured by Nippon Synthetic Chemical Industry Co., Ltd., 12.88%)
(3) Crosslinker A (described below, 50% aqueous solution) 1.42 parts (4) Ethylene oxide surfactant 4.30 parts (C ₁₂ H ₂₅ O (CH ₂ CH ₂ O) ₁₀ H, 1.66 % Methanol solution)

  The structural formulas of the compounds used in the examples are shown below.

[Calendar processing]
The obtained base paper on which the coating layer was formed was adjusted to a density of 1.0 g / m ³ by soft calendering and machine calendering.

[Formation of water-resistant resin coating layer]
On the felt surface of the calendered base paper, after corona discharge treatment, 10 parts of high-density polyethylene containing 10 parts of anatase-type titanium oxide and a trace amount of ultramarine and 30 parts of low-density polyethylene are hot melt extruded. The film was coated to 30 μm with a machine to form a water-resistant resin coating layer having a glossy surface.

[Preparation of support for recording material]
After the corona discharge treatment is applied to the wire surface (back surface) of the base paper on which the water-resistant resin coating layer is formed on the felt surface of the base paper, high-density polyethylene is coated to a resin thickness of 35 μm, and the back surface resin layer comprising the mat surface To obtain a recording material support of the present invention.

(Evaluation)
A photosensitive material for color was applied to the felt surface of the obtained recording material support to produce a photosensitive material, and the following evaluation was performed. The results are shown in Table 1.

[Peelability of water-resistant resin coating layer]
The resulting photosensitive material is developed using Frontier 390 (Fuji Photo Film Co., Ltd.) to create a solid black image, and the visual evaluation of peeling of the water-resistant resin coating layer is performed according to the following criteria. It was.

(Evaluation criteria)
○: No peeling occurred at the end.
(Triangle | delta): Peeling has generate | occur | produced in a part of edge part.
X: The edge part has peeled off.

[Flatness]
Visuality of the flatness was evaluated.

(Evaluation criteria)
◯: Surface irregularities due to the formation of paper and fibers are hardly observed, and are sufficiently satisfactory.
Δ: Slight irregularities on the surface due to the formation of the paper and fibers are observed, but satisfactory.
X: Unevenness due to surface irregularities observed.

<Example 2>
A support for recording material was prepared in the same manner as in Example 1 except that (1) to (4) were changed as described in Table 1 below in “Formation of coat layer” in Example 1. The same evaluation was performed. The results are shown in Table 1.

<Comparative Example 1>
A support for recording material was prepared in the same manner as in Example 1 except that (1) to (4) were changed as described in Table 1 below in “Formation of coat layer” in Example 1. The same evaluation was performed. The results are shown in Table 1.

<Comparative example 2>
A support for recording material was prepared in the same manner as in Example 1 except that (1) to (4) were changed as described in Table 1 below in “Formation of coat layer” in Example 1. The same evaluation was performed. The results are shown in Table 1.

<Comparative Example 3>
A recording material support was prepared in the same manner as in Example 1 except that no coat layer was formed in “Formation of Coat Layer” in Example 1, and the same evaluation as in Example 1 was performed. The results are shown in Table 1.

  As is clear from Table 1, the photosensitive material using the recording material support of the present invention does not show peeling or infiltration of the developer, and the recording material support of the present invention has flatness and water resistance. It turns out that it is excellent. On the other hand, the photosensitive material using the recording material support of Comparative Examples 1 and 2 is peeled off at the end and discolored due to the infiltration of the developer, and the comparative recording material support is not good. I understand that. Further, it can be seen that the photosensitive material using the support for recording material of uncoated paper of Comparative Example 3 has poor planarity and is not good.

Claims (7)

  A support for recording material having a water-resistant resin coating layer on at least one surface of a base paper, having a coat layer containing a hydrophilic binder between the base paper and the water-resistant coating layer, A support for recording material, wherein the binder is crosslinked.   2. The support for recording material according to claim 1, wherein the hydrophilic binder contains one or more selected from polyvinyl alcohols and gelatins.   3. The recording material support according to claim 2, wherein the polyvinyl alcohol is acetoacetyl-modified polyvinyl alcohol.   The recording material support according to any one of claims 1 to 3, wherein the coating layer further contains a water-soluble fluorescent brightening agent.   The recording material support according to claim 1, wherein the coating layer further contains an inorganic pigment.   The water-resistant resin coating layer is made of at least one selected from polyethylene and polypropylene, and the water-resistant resin coating layer is produced by a melt extrusion laminating method. 2. A support for recording material according to item 1.   7. The recording material support according to claim 1, wherein the recording material support is for a silver halide photographic light-sensitive material.