JPH09265155A - Supporting body for image material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an image material having good curling property and cutting property and good processing property for forming and the like, and to provide a resin-coated paper type supporting body for an image material which can be used for printing. SOLUTION: This supporting body for an image material consists of a paper essentially comprising natural pulp as a substrate. The surface of the paper substrate where an image forming layer is to be formed is coated with a resin coating layer (A) having a film forming ability, and the opposite surface of the paper substrate is coated with a resin layer (B) essentially comprising a polyethylene resin. In this case, the Taber's rigidity specified by JIS P8125 in the paper making direction of the paper substrate is 12 gf.cm to 20 gf.cm. The IR dichroic ratio (D value) of the resin layer (B) specified by the following is <=0.85, and the coating amt. of the resin layer (B) is 10g/m<2> to 27g/m2 .

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention In the present invention, a paper containing natural pulp as a main component is used as a substrate, and one of the paper substrates provided with an image forming layer (hereinafter sometimes referred to as base paper) has a film forming ability. The present invention relates to a resin-coated support for paper-type image material, which is coated with a resin layer (A) containing a certain resin, and the paper substrate on the opposite side is coated with a resin layer (B) containing a polyethylene-based resin. The present invention relates to an image material having excellent curl properties and cuttability, excellent moldability and the like, and a resin-coated paper-type image material support capable of providing a print thereof.

[0002]

2. Description of the Related Art Conventionally, a resin-coated paper type support having a base paper surface coated with a resin capable of forming a film has been well known. For example, Japanese Patent Publication No. 55-12584 discloses a technique for a photographic support in which a base paper is coated with a resin capable of forming a film, preferably a polyolefin resin. U.S. Pat. No. 3,501,298 discloses a technique for a photographic support in which both sides of a base paper are coated with a polyolefin resin. In addition, since the rapid photographic development method of silver halide light-sensitive materials was applied, a photographic support in which both sides of a base paper are coated with a polyethylene resin has been mainly put into practical use for photographic printing paper, If necessary, one resin layer on the image forming side usually contains a titanium dioxide pigment in order to impart sharpness.

US Pat. No. 4,774,224 supports resin-coated paper having a surface roughness of resin coating of 7.5 microinch-AA or less, particularly polyethylene resin-coated paper having a base paper surface coated with polyethylene resin. A thermal transfer recording image receiving element having a body has been proposed. In addition, JP-A-63-307
Japanese Patent Publication 979 discloses a technique relating to an ink jet recording sheet having a resin-coated paper as a support.

However, the resin-coated paper-type image material support based on paper containing natural pulp as a main component still has serious problems in terms of quality, and still satisfactory results have been obtained. The reality is not.

The curl of the image material obtained by coating the image forming layer and the auxiliary functional layer on the resin-coated paper-type support and the curl of the print are as follows. From the standpoint of print appreciation and ease of sticking to an album or the like, it is desired that the image material and the print thereof have a slightly negative curl (curl to the back side opposite to the image forming layer) and are extremely flat.

However, when the image forming layer is provided, the contracting force of the binder contained in the image forming layer and the auxiliary functional layer causes a pulling force toward the image forming layer side, and the image material and its print are curled positively. (Curling toward the image forming layer side) occurs. This problem is particularly pronounced in silver halide photographic materials and photographic prints that use gelatin, which has a large shrinkage force, as the main binder, and is even more pronounced in low humidity environments.

In order to prevent the occurrence of the positive curl of this image material and its print, the back resin layer of the resin-coated paper used as a support is made thicker and pulled in advance to the back side opposite to the image forming layer. Is often done. However, the resin-coated paper having a thick backing resin layer, the image material using the paper as a support, and the print thereof have a problem that the cutting property is deteriorated. That is, the support for the image material or the image material having the support for the image material is a guillotine cutter or a precision print cutter.
Although it is cut to a desired size with a cutter such as a (precision print cutter), the support for image material is not cut accurately at this time, and a whisker-like object is generated from the cut surface of the support for image material. The problem of reducing the commercial value often occurred.

Therefore, there have been proposed techniques relating to several back resin layers for the purpose of improving the curling property or cutting property of a resin-coated paper type photographic support. Japanese Patent Publication 48-9963
The publication discloses a photographic support having good curl physical properties, which is obtained by coating a base paper with a resin composition consisting of low density polyethylene resin: high density polyethylene resin = 1: 1. Further, in JP-A-58-95732, the density is 0.9
More than 45g / cm ³ and melt index is 15g / 10
40 to 75 parts by weight of a high-density polyethylene resin having a density of 40 to 10 g / min and a density of 0.930 g / cm ³ or less,
A base material coated with a polyethylene resin composition comprising 60 parts by weight to 25 parts by weight of a low-density polyethylene resin having a melt index of 1 g / 10 min to 40 g / 10 min, and a photographic support having good cuttability and curl properties. There is disclosure about the body. Further, JP-A-5-40327 has a density of 0.935 g / cm ^3.
Below, melt index 0.2g / 10min-4g /
95 parts by weight of a low-density polyethylene resin having a density of 0.945 g / cm ³ or more and a melt index of 18.5 g / 10 minutes-50 g / 10 minutes with 5 to 25 parts by weight of a low-density polyethylene resin of 10 minutes. There is a disclosure of a photographic support in which a base paper is coated with a polyethylene resin composition consisting of 1 part to 75 parts by weight and which has good cuttability, curl physical properties and molding processability. Furthermore, JP-A-6-230517 and JP-A-6-2660.
No. 46, JP-A 7-36147, the critical shear rate is coated with a resin composition consisting of a high-density polyethylene resin and a low-density polyethylene resin whose critical shear rate is less than a specific value, cutability and There is a disclosure of a support for image materials which has good curl properties and does not generate gel.

However, even if a resin-coated paper obtained by coating a base paper with a resin composition comprising a low-density polyethylene resin and a high-density polyethylene resin disclosed in these prior arts is used as a support, those problems can be sufficiently improved. There wasn't.

[0010]

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to use a paper mainly composed of natural pulp as a substrate, and one of the paper substrates on which an image forming layer is provided (hereinafter referred to as a base paper. A) is coated with a resin layer (A) containing a resin capable of forming a film, and the paper substrate on the opposite side is coated with a resin layer (B) containing polyethylene resin as a main component. Since it is a support, it has very good curl properties and cuttability, therefore there is no problem of processability by processing equipment when making prints from image materials, and the appreciation of finished prints and albums etc. An object of the present invention is to provide a support for a resin-coated paper-type image material, which is excellent in quality such as ease of sticking and can be formed into a good image material and a print thereof. Other objects of the present invention are:
It will be apparent from the description below.

[0011]

In order to solve the above-mentioned problems, the inventors of the present invention have made earnest studies and as a result, as a result, paper having natural pulp as a main component is used as a base, and an image forming layer of the paper base is provided. The resin layer (A) on the side of which the paper substrate surface is capable of forming a film
Then, in a support for an image material in which a paper base surface on the opposite side is covered with a resin layer (B) containing a polyethylene resin as a main component, the Taber stiffness defined by JIS P 8125 in the paper making direction of the paper base is The resin layer (B) has an infrared dichroic ratio (D) of 12 gf · cm to 20 gf · cm.
Value) is 0.85 or less, and the image material support the coating amount of the resin layer (B) is characterized in that it is a ^{10g / m 2 ~27g / m 2} , the purpose is achieved of the present invention Turned out to be.

Infrared dichroic ratio (D value): The resin layer (B) coated on the side opposite to the side on which the image forming layer is provided without the back layer is the aqueous solution of sodium hypochlorite. Peeled from the paper substrate by, the infrared absorption spectrum of the peeled film is measured by the infrared light polarized by the polarizing plate,
72 derived from the lateral vibration of CH ₂ of the polyethylene molecule
0 cm ^-1 Request peak intensity of 720 cm ^-1 towards the front and rear in the two infrared absorption peaks of before and after the 730 cm ^-1 before and after. The peak intensity of absorbance was determined smallest point and the line connecting the absorbance in the 725cm ^-1 ~775cm ^-1 of the most absorbance small point in the 675cm ^-1 ~725cm ^-1 as a baseline It is a value. At this time, the peak intensity A (=) around 720 cm ⁻¹ by infrared light polarized parallel to the traveling direction (longitudinal direction) at the time of melt extrusion and the infrared light polarized vertically The peak intensity A (+) around 720 cm ^-1 was obtained, and the ratio of A (=) / A (+) was calculated by the infrared dichroic ratio (D
Value).

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION To measure the above infrared dichroic ratio (D value) of a resin layer (B) having a back layer in the present invention, for example, the back layer on the surface of the resin layer is completely removed. You can do it. Further, depending on the constitution of the back layer, the binder in the back layer may be dissolved by using an aqueous solution of sodium hypochlorite or the like so as not to affect the physical properties of the resin layer, so that the binder can be completely removed and measured. At this time, it is possible to determine whether or not it is completely removed by measuring infrared absorption and the like.

The object of the present invention is to use only a base paper having a Taber stiffness of 12 gf · cm to 20 gf · cm in the papermaking direction or a infrared ray as a resin layer (B) containing a polyethylene resin as a main component. dichroic ratio and the (D value) of 0.85 or less, it can not be sufficiently achieved only by using a material obtained by coating amount of ^{10g / m 2 ~27g / m 2} , by a combination thereof, synergistically achieved The present invention has been accomplished by finding out what is done.

The base paper used in the practice of the present invention includes:
Taber stiffness in the papermaking direction of the base paper is 12 gf ・ cm to 20 gf ・ cm
Is used. If a base paper with a Taber stiffness in the papermaking direction of less than 12 gf · cm is used, the image material and its prints tend to curl, especially in a low humidity environment. And the ease of sticking to albums, etc.
If it is larger than 20 gf · cm, curling curl of the rolled image material becomes large, and the curl property of the print is deteriorated, which is a problem.

The base paper having a Taber stiffness of 12 gf · cm to 20 gf · cm in the papermaking direction of the base paper used for carrying out the present invention is (1) selection of pulp grade, (2) selection of pulp beating conditions,
(3) Selection of type and amount of added chemicals (particularly paper strength enhancer),
(4) It can be obtained by adjusting the thickness and density,
In order to obtain an image material having good surface quality and excellent smoothness, it is preferable that the thickness unevenness index Rpy in the papermaking direction of the base paper defined below is 250 mV or less.
It is more preferably 00 mV or less, most preferably 150 mV or less. The film thickness unevenness index Rpy referred to here is
Using a film thickness measuring instrument that runs a sample between two spherical stylus and measures the thickness variation of the sample as an electric signal through an electronic micrometer, the sensitivity range of the electronic micrometer is ± 15 μm / ± 3 V Then, the thickness variation in the papermaking direction of the sample was measured by scanning at a constant speed of 1.5 m / min in the papermaking direction of the sample after the zero point adjustment, and the obtained measurement signal value was measured using an FFT analyzer. Fast Fourier transform using a Hanning window for the window, and the power spectrum (unit: m
It is a value (unit: mV) obtained by obtaining V ² ) and summing the power values in the frequency range of ² Hz to 25 Hz and multiplying by 2/3.

As a method for producing a base paper which is preferably used in the practice of the present invention and has a Taber stiffness of 12 gf · cm to 20 gf · cm in the paper making direction and a thickness unevenness index Rpy of 250 mV or less, Is 30% by weight or more, preferably 50% by weight or more of hardwood pulp which is short fiber and easily smooth, and is beaten with a beater so that the long fiber content is reduced as much as possible. For example, beating of the pulp is preferably such that the length-weighted average fiber length of the beating pulp is 0.4 mm to 0.75 mm. Next, an appropriate papermaking method was applied to the stock slurry added with the internal additive chemicals selected to have an appropriate Taber stiffness (especially the type and amount of the paper strengthening agent influences the stiffness). It is preferable to use a fourdrinier paper machine to fabricate the base paper so that a uniform texture is obtained. Specifically, for example, using a Fourdrinier paper machine having an appropriate upper dewatering mechanism as described or exemplified in JP-A-61-284762, which gives an appropriate turbulence to a stock slurry, wet part As a press, a multi-stage wet press, preferably a wet press with three or more stages, and a smoothing crawl at the final stage of the press part are combined so that a uniform texture can be obtained by combining appropriate papermaking methods. Papermaking, and after papermaking, calendering is performed using a machine calender, super calender, thermal calender, etc. to obtain a density of 0.95 g / cm ^{3 to} 1.1.
By setting the range to be 5 g / cm ³ , it is possible to produce a base paper having a Taber stiffness of 12 gf · cm to 20 gf · cm in the paper making direction and a thickness unevenness index Rpy of 250 mV or less. If the density is less than 0.95 g / cm ³ or larger than 1.15 g / cm ³ , the film thickness unevenness index Rpy tends to be larger than 250 mV.

The base paper used in the practice of the present invention is preferably natural pulp paper with an appropriately selected natural pulp,
It may be a mixed paper made of natural pulp, synthetic pulp and synthetic fiber. Natural pulp was subjected to usual bleaching treatment such as chlorine, hypochlorite, chlorine dioxide bleaching, alkali extraction or alkali treatment and, if necessary, oxidative bleaching treatment with hydrogen peroxide, oxygen, etc., and a combination thereof. Wood pulp of softwood pulp, hardwood pulp, mixed wood of hardwood and hardwood is advantageously used, and various types of recycled pulp (waste paper pulp) other than kraft pulp, sulfite pulp, soda pulp and the like can be used. .

The base paper containing natural pulp as a main component, which is preferably used in the practice of the present invention, preferably contains an appropriate amount of various additives appropriately selected at the time of preparing the stock slurry. As a sizing agent, fatty acid metal salt or fatty acid, alkyl ketene dimer emulsion or epoxidized higher fatty acid amide, alkenyl or alkyl succinic anhydride emulsion, rosin derivative, etc. described in Japanese Patent Publication No. 62-7534, dry paper, etc. As a strength enhancer, anionic, cationic or amphoteric polyacrylamide, polyvinyl alcohol, cationized starch, vegetable galactomannan, etc., as a wet paper strength enhancer, polyamine polyamide epichlorohydrin resin, etc., as a filler, clay,
Kaolin, calcium carbonate, titanium oxide, etc., as a fixing agent, water-soluble aluminum salts such as aluminum chloride, vanadium sulfate, etc., and as a pH adjusting agent, caustic soda, sodium carbonate, etc.
Da, sulfuric acid, etc., JP-A-63-204251, JP-A 1-2
It is advantageous to incorporate the coloring pigments, coloring dyes, fluorescent whitening agents and the like described or exemplified in JP-A-66537 or the like in an appropriate combination.

Further, in or on the base paper mainly composed of natural pulp which is preferably used in the practice of the present invention,
A composition comprising various water-soluble polymers or hydrophilic colloids or latexes, antistatic agents, and additives may be contained or applied by size press or tab size press or coating such as blade coating or air knife coating. it can. As a water-soluble polymer or hydrophilic colloid, as described in JP-A 1-266537 or exemplified starch-based polymer, polyvinyl alcohol-based polymer, gelatin-based polymer, polyacrylamide-based polymer, cellulose-based polymer, emulsion, latex, Petroleum resin emulsion, JP-A-55-4
No. 027, an emulsion or latex of a copolymer having ethylene and acrylic acid (or methacrylic acid) described or exemplified in JP-A 1-180538 at least as a constituent, styrene-butadiene-based, styrene-acrylic-based, Vinyl acetate-acrylic, ethylene-vinyl acetate-based, butadiene-methyl methacrylate-based copolymers and emulsions or latexes of carboxy-modified copolymers thereof, as antistatic agents, alkali metal salts such as sodium chloride and potassium chloride, Clay, pigments such as alkaline earth metal salts such as calcium chloride and barium chloride, colloidal metal oxides such as colloidal silica, organic antistatic agents such as polystyrene sulfonate, etc.
Kaolin, calcium carbonate, talc, barium sulfate, titanium oxide, etc., as a pH adjuster, hydrochloric acid, phosphoric acid, citric acid, caustic soda, etc., as well as the above-mentioned color pigments, coloring dyes, optical brighteners and other additives are appropriately combined. It is advantageous to include them.

Regarding the thickness of the base paper used in the practice of the present invention, the Taber stiffness in the paper making direction of the base paper is 12 gf · cm to
There is no particular limitation as long as it is 20 gf · cm, but the thickness is 12
It is preferably 0 μm to 200 μm.

Back resin layer (B) used for carrying out the present invention
If the infrared dichroic ratio (D value) is 0.85 or less, the polyethylene resin contained in
Various polyethylene resins are useful, but those having an infrared dichroic ratio (D value) of 0.75 or less are more preferable, and 0.65 or less, from the viewpoint of the effect of improving curl physical properties and cutting properties. And those having a value of 0.55 or more are particularly preferable.
When the infrared dichroic ratio (D value) is less than 0.55, the moldability of the resin composition for the back resin layer tends to deteriorate. As the polyethylene resin for the back resin layer used in the practice of the present invention, the melt flow rate specified by JIS K 6760 is 10 g / 10 min to 40 g / 10 min, and the density is 0.960 g / cm ³ or more. 90 parts by weight to 65 parts by weight of high density polyethylene resin, low density polyethylene having a melt flow rate of 0.2 g / 10 minutes to ³ g / 10 minutes and a density of 0.935 g / cm ³ or less as defined by JIS K 6760. A compound resin composition prepared by previously melting and mixing 10 parts by weight to 35 parts by weight of a resin or a medium density polyethylene resin is preferable.

The high-density polyethylene resin for the back resin layer (B) which is preferably used in the practice of the present invention has a density of 0.960 g / cm ³ or more, and JIS K 6
760 melt flow rate (hereinafter, JIS
The melt flow rate specified by K 6760 is simply M
FR) is in the range of 10 g / 10 min to 40 g / 10 min, and the infrared dichroic ratio (D value) of the resin layer (B) is 0.8.
As long as it is 5 or less, various density, MFR, molecular weight, and molecular weight distribution can be used alone or in combination, and ordinary high density polyethylene resin, ethylene and propylene, α-olefins such as butylene can be used. Various materials such as copolymers with and mixtures thereof can be used.

The MFR of the high density polyethylene resin for the back resin layer (B) preferably used in the practice of the present invention is in the range of 10 g / 10 min to 40 g / 10 min, particularly preferably 10 g / 10. The range is from minutes to 30 g / 10 minutes. If the MFR of the resin is lower than 10 g / 10 minutes, the infrared dichroic ratio (D value) tends to be large, curling properties and cuttability tend to be poor, and the adhesiveness between the base paper and the resin layer and high-speed processing If it is higher than 40 g / 10 minutes, the mixing property of the resin and the molding processability will be deteriorated, which is a problem. Also,
The density of high density polyethylene resin is 0.960g
/ Cm ³ or more, but if the density is lower than 0.960 g / cm ³ , the elastic modulus of the resin layer becomes low and curl properties, stiffness, etc. deteriorate, which is a problem, preferably 0.962 g / cm ³ or more. is there.

The low-density polyethylene resin or the medium-density polyethylene resin for the back resin layer (B) which is preferably used in the practice of the present invention has a density of 0.935 g / cm ³ or less and an MFR of 0.2 g / 10 min. ˜3 g / 10 min, and the resin layer (B) has an infrared dichroic ratio (D value) of 0.85.
Any of those having various densities, MFRs, molecular weights and molecular weight distributions can be used alone or in combination as long as they are as follows. For example, high-pressure low-density polyethylene resin (autoclave low-density polyethylene resin, tubular low-density polyethylene resin), linear low-density polyethylene resin, medium-density polyethylene resin, ethylene and propylene,
Various materials such as a copolymer with α-olefin such as butylene, a carboxy-modified polyethylene resin and a mixture thereof can be used.

The MFR of the low-density polyethylene resin or the medium-density polyethylene resin for the back resin layer (B) preferably used in the practice of the present invention is 0.2 g / 10 min.
It is in the range of 3 g / 10 minutes, but if it is less than 0.2 g / 10 minutes, the mixing property of the resin, the adhesiveness between the base paper and the resin layer, the high-speed processability and the like are deteriorated, which is a problem. If it is higher than this, the molding processability tends to be poor, the infrared dichroic ratio (D value) tends to be high, and the curl properties and cutting properties tend to be poor, which is a problem, and more preferably 0.2 g / 10 min. ˜2 g / 10 min, particularly preferably 0.2 g / 10 min to less than 1 g / 10 min.
The density of the low-density polyethylene resin or the medium-density polyethylene resin is 0.935 g / cm ³ or less,
If the density is higher than 0.935 g / cm ³ , the molding processability of the resin composition and the adhesion between the base paper and the resin layer will be deteriorated, which is a problem, and preferably 0.930 g / cm ³ or less. As for the molecular weight distribution of the resin, the fraction having a molecular weight of 500,000 or more is preferably 10% by weight or more, and particularly preferably 12% by weight or more. If the fraction of the resin having a molecular weight of 500,000 or more is less than 10% by weight, molding processability, especially neck-in becomes large, which is not preferable. Here, the molecular weight is measured by Waters 150-C (column: Tosoh GMH).
-XL HT 8mmφ × 30cm × 3, solvent: 1,2,4
-Trichlorobenzene, temperature: 135 ° C, flow rate: 1 ml / m
in) using the GPC method.

The amount of the high-density polyethylene resin used in the compound resin composition comprising the high-density polyethylene resin and the low-density or medium-density polyethylene resin preferably used in the practice of the present invention is 90 to 65 parts by weight. And preferably in the range of 85 to 70 parts by weight. When the amount of the resin used is less than 65 parts by weight, the infrared dichroic ratio (D value) of the resin layer (B) becomes high, and the curl properties and cuttability of the image material support are deteriorated, which is a problem. However, if it is more than 90 parts by weight, resin mixing property, molding processability,
This is a problem because the adhesiveness between the base paper and the resin layer is poor.

As the polyethylene resin for the back resin layer used in the practice of the present invention, a compound resin prepared by melting and mixing in advance is preferable. As a method for preparing a compound resin by previously melting and mixing a low-density polyethylene resin or a medium-density polyethylene resin and a high-density polyethylene resin, a simple melt mixing method, a multi-stage melt mixing method, or the like can be used. For example, using an extruder, a twin-screw extruder, a heating roll mill, a Banbury mixer, a pressure kneader, and the like, a predetermined amount of low-density or medium-density polyethylene resin and high-density polyethylene resin, and if necessary, an antioxidant A method of adding various additives such as a lubricant, melting and mixing, and then pelletizing the mixture is advantageously used. When polyethylene resin is not used as a compound resin and directly added to the melt extrusion machine in the state of simple mixing and melt extrusion coating is performed, adhesion between the base paper and the resin layer, resin mixability, molding process It is a problem because the sex etc. deteriorates.

Further, the coating amount of the back resin layer (B) of the support for image materials used in the practice of the present invention is 10 g / m ^{2 to} 27 g /
m ² but selected in this range for proper curl of the image material and its prints. Coverage is 10g / m ²
If it is less than 27 g, the molding processability of the resin and the adhesiveness between the base paper and the resin layer will be deteriorated, and if it is more than 27 g / m ² , the cutting property of the support for image materials will be deteriorated, causing a problem. .

The side of the base paper of the support for image materials of the present invention on which the image forming layer is provided is covered with a resin layer (A) containing a resin capable of forming a film. As the resin capable of forming a film, a thermoplastic resin such as a polyolefin resin, a polycarbonate resin, a polyester resin, a polyamide resin and a mixture thereof is preferable, and among them, the above-mentioned polyolefin resin is more preferable from the viewpoint of melt extrusion coating property, and a polyethylene resin is preferable. Resins are particularly preferred. Further, it may be covered with a resin layer made of an electron beam curable resin described or exemplified in JP-B-60-17104.

The polyethylene resin for the surface resin layer (A) preferably used in the practice of the present invention includes low density polyethylene resin, medium density polyethylene resin, high density polyethylene resin, linear low density polyethylene resin and ethylene. Various substances such as copolymers with α-olefins such as propylene and butylene, carboxy-modified polyethylene resin and the like and mixtures thereof can be used. Also, various densities, M
FR, molecular weight and molecular weight distribution can be used, but usually, density is 0.91 g / cm ^{3 to} 0.97 g / cm ³ , MF
R1 g / 10 min to 30 g / 10 min and a molecular weight in the range of 20,000 to 250,000 can be advantageously used alone or as a mixture.

The image material support of the present invention comprises a polyethylene resin composition for a back resin layer on a running base paper, and a resin in the front resin layer is a thermoplastic resin, preferably a polyolefin resin, and particularly preferably polyethylene. In the case of a system resin, the resin composition for the surface resin layer is produced by a so-called melt extrusion coating method, in which a resin composition for the surface resin layer is cast from the slit die into a film shape and coated. Usually, using a melt extruder on the running base paper, the resin composition melted from the slit die is extruded in a film form, cast and coated, pressure-bonded between the pressure roll and the cooling roll, It is produced in a series of steps of peeling from the cooling roll. At this time, the temperature of the molten film is preferably 280 ° C to 340 ° C.
As the slit die, a flat die such as a T-type die, an L-type die, or a fishtail type die is preferable, and the slit opening diameter is desirably 0.1 mm to 2 mm. Before coating the resin composition on the base paper, the base paper is preferably subjected to an activation treatment such as a corona discharge treatment or a flame treatment. Further, as described in JP-B-61-42254, a resin layer may be coated on a running base paper after spraying an ozone-containing gas onto a molten resin composition in contact with the base paper. Also,
It is preferable that the front and back resin layers are sequentially, preferably continuously, extrusion coated, that is, the base paper is coated by a so-called tandem extrusion coating method, and if necessary, two or more front or back resin layers are coated. In a multi-layer configuration,
You may coat by a multilayer extrusion coating method. The surface resin layer surface of the image material support has a glossy surface.
It can be processed to a fine rough surface, matte surface or silk surface described in JP-19732-A, and the back resin layer is usually preferably processed to a matte surface.

The coating amount of the surface resin layer (A) of the image material support in the present invention is not particularly limited,
Range of 9g / m ² ~60g / m ² are useful, preferably 12
in the range of ^{g / m 2 ~45g / m 2} .

Various additives can be contained in the front and back resin layers of the support for image materials in the present invention. Japanese Patent Publication No. 60-3430, Japanese Patent Publication No. 63-11655, 1-382
No. 91, Japanese Examined Patent Publication No. 1-38292, and titanium oxide, zinc oxide, talc described or exemplified in each publication such as JP-A-1-105245.
White pigments such as calcium carbonate, fatty acid amides such as stearamide and arachidic amide, zinc stearate, calcium stearate, aluminum stearate, magnesium stearate, zinc palmitate, zinc myristate, and fatty acid metal salts such as calcium palmitate Hindered phenols described in or described in JP-A-1-105245, hindered amines, phosphorus, various antioxidants such as sulfur, cobalt blue, ultramarine, celian blue, blue pigments and dyes such as phthalocyanine blue,
Magenta pigments and dyes such as cobalt violet, fast violet and manganese violet.
Various additives such as a fluorescent whitening agent and an ultraviolet absorber described or exemplified in Japanese Patent No. 254440 can be appropriately combined and contained. The additives are preferably contained as a resin masterbatch or compound. In particular, as a method of incorporating these additives in the compound resin composition for the back resin layer used in the practice of the present invention, a high-density polyethylene resin and a low-density polyethylene resin or a medium-density polyethylene resin, Alternatively, it may be added at the time of preparing the compound resin, or a masterbatch added at a high concentration to the resin may be prepared in advance, and the masterbatch may be added to the resin at the time of melt extrusion coating.

The surface of the surface resin layer of the support for image materials in the present invention is subjected to activation treatment such as corona discharge treatment and flame treatment, and then, JP-A-61-84643 and JP-A-1-92740,
An undercoat layer described or exemplified in JP-A-1-102551, JP-A-1-66035 and the like can be applied.

Further, after the activation treatment such as corona discharge treatment and flame treatment is applied to the back resin layer surface of the support for image material in the present invention, various back layers are coated to prevent electrification and the like. can do. Further, in the back layer, inorganic antistatic agents such as colloidal silica, colloidal alumina, hectorite clay colloids and mixtures thereof described or exemplified in JP-A-5-107688, binders, organic antistatic agents or both. JP-A-59-214 for the purpose of
A water-soluble synthetic polymer compound or a salt thereof having a carboxyl group or a sulfone group described or exemplified in 849 publication, a hydrophilic synthetic polymer colloid substance or a salt thereof, a polymer described or exemplified in JP-A-59-214849 Latex, starch described or exemplified in JP-A-58-14131, polyvinylpyrrolidone described or illustrated in JP-A-58-45248, polyvinyl alcohol described or illustrated in JP-A-62-220950, Kaisho 63-1
Polymers such as chitosan described or exemplified in 89859, curing agents described or exemplified in JP-B-58-56859, matting agents or surfactants described or exemplified in JP-A-59-21849. It may be contained in an appropriate combination.

As a device for applying the coating liquid for the back layer, an air knife coater, a roll coater, a bar coater, a blade coater, a slide hopper coater,
Examples thereof include a gravure coater, a flexo gravure coater and a combination thereof. Further, as a drying device for the applied coating liquid, there are various types such as a straight tunnel dryer, an arch dryer, an air loop dryer, a hot air dryer such as a sine curve air float dryer, an infrared heating dryer, and a dryer using a microwave or the like. A drying device can be mentioned.

The support for image materials in the present invention is coated with various photographic constituent layers and is used for color photographic printing paper, black and white photographic printing paper, typesetting photographic paper, copy photographic paper and reversal photographic material. , Silver salt diffusion transfer method, negative and positive, and printing materials. For example, silver chloride, silver bromide, silver chlorobromide, silver iodobromide, and silver chloroiodobromide emulsion layers can be provided. The silver halide photographic emulsion layer can contain a color coupler to provide a multilayer silver halide color photographic constituent layer. Further, a photographic component layer for a silver salt diffusion transfer method can be provided. As the binder for the photographic constituent layers, hydrophilic polymer substances such as polyvinylpyrrolidone, polyvinyl alcohol and sulfate compounds of polysaccharides can be used in addition to ordinary gelatin. Further, the above-mentioned photographic constituent layer can contain various additives. For example, as sensitizing dyes, cyanine dyes, merocyanine dyes, etc., as chemical sensitizers, water-soluble gold compounds, sulfur compounds, etc., as antifoggants or stabilizers, hydroxy-triazolopyrimidine compounds, mercapto-heterocyclic compounds, etc. , Hardening agents such as formalin, vinylsulfone compounds and aziridine compounds, coating aids such as alkylbenzenesulfonates and sulfosuccinate salts, etc., dialkylhydroquinone compounds etc. as antifouling agents, and other fluorescent brighteners, improving sharpness Dye, antistatic agent, pH adjuster,
A fogging agent and a water-soluble iridium compound, a water-soluble rhodium compound, and the like at the time of generation and dispersion of silver halide may be incorporated in an appropriate combination.

The photographic material according to the present invention is exposed, developed and stopped as described in "Photosensitive Material and Handling Method" (Kyoritsu Shuppan, Goro Miyamoto, Photographic Engineering Course 2) according to the photographic material. , Fixing, bleaching, stabilizing, etc. can be performed. Further, the multi-layer silver halide color photographic material may be treated with a developer containing a development accelerator such as benzyl alcohol, thallium salt, phenidone or the like, or may be treated with a developer substantially free of benzyl alcohol. it can.

The image material support of the present invention can be used as various thermal transfer recording image receiving material supports provided with various thermal transfer recording image receiving layers coated thereon. As the synthetic resin used for the thermal transfer recording image-receiving layer, a resin having an ester bond such as polyester resin, polyacrylic ester resin, polycarbonate resin, polyvinyl acetate resin, polyvinyl butyral resin, styrene acrylate resin, and vinyltoluene acrylate resin. , Resins having urethane bonds such as polyurethane resins, resins having amide bonds such as polyamide resins, resins having urea bonds such as urea resins, other polycaprolactam resins, styrene resins, polyvinyl chloride resins, vinyl chloride-vinyl acetate Examples thereof include copolymer resins and polyacrylonitrile resins. In addition to these resins, mixtures or copolymers thereof can be used.

In the thermal transfer recording image-receiving layer according to the present invention,
In addition to the above synthetic resin, a release agent, a pigment or the like may be added. Examples of the releasing agent include solid waxes such as polyethylene wax, amide wax, and Teflon powder, fluorine-based waxes,
Examples thereof include phosphate ester type surfactants and silicone oils. Among these release agents, silicone oil is most preferred. As the silicone oil, an oily substance can be used, but a curable type is preferred. Examples of the curable silicone oil include a reaction curable type, a photocurable type, and a catalyst curable type, and a reaction curable type silicone oil is particularly preferable. Examples of the reaction-curable silicone oil include an amino-modified silicone oil and an epoxy-modified silicone oil. The amount of the reactive silicone oil added is preferably 0.1 to 20 wt% in the image receiving layer. As the pigment, extender pigments such as silica, calcium carbonate, titanium oxide and zinc oxide are preferable. Further, the thickness of the image receiving layer is preferably 0.5 to 20 μm, and 2
More preferably, it is 10 μm.

The support for image materials in the present invention can be used as a support for various ink jet recording materials by coating various ink receiving layers. Various binders may be contained in these ink receiving layers for the purpose of improving the drying property of the ink and the sharpness of the image. Specific examples of these binders include lime-processed gelatin, acid-processed gelatin, enzyme-processed gelatin, gelatin derivatives, and various gelatins such as gelatin reacted with an anhydride of a dibasic acid such as phthalic acid, maleic acid and fumaric acid. , Ordinary polyvinyl alcohol with various degrees of saponification,
Carboxy-modified, cation-modified and amphoteric polyvinyl alcohols and their derivatives, oxidized starch, cationized starch, etherified starch and other starches, carboxymethyl cellulose, hydroxyethyl cellulose and other cellulose derivatives, polyvinylpyrrolidone, polyvinylpyrrolidone. Dihalide, sodium polyacrylate, acrylic acid methacrylic acid copolymer salt, polyethylene glycol, polypropylene glycol, polyvinyl ether, alkyl vinyl ether / maleic anhydride copolymer, styrene / maleic anhydride copolymer and salts thereof, polyethylene Synthetic polymers such as imines, styrene-butadiene copolymers, conjugated diene-based copolymer latex such as methylmethacrylate-butadiene copolymers, polyvinyl acetate, vinyl acetate
Vinyl acetate polymer latex such as maleic acid ester copolymer, vinyl acetate / acrylic acid ester copolymer, ethylene / vinyl acetate copolymer, acrylic acid ester polymer, methacrylic acid ester polymer, ethylene / acrylic acid ester Acrylic polymer or copolymer latex such as copolymer, styrene / acrylic acid ester copolymer, vinylidene chloride copolymer latex, etc. or a functional group-containing unit such as carboxyl group of these various polymers Functional group-modified polymer latex by body, water-based adhesive such as thermosetting synthetic resin system such as melamine resin, urea resin and polymethylmethacrylate, polyurethane resin, unsaturated polyester resin, vinyl chloride / vinyl acetate copolymer, polyvinyl butyral, Synthetic resin adhesive such as alkyd resin, Japanese Patent Publication No. 3-24906 No., JP-A-3-281383,
Inorganic binders such as alumina sols and silica sols described or exemplified in Japanese Patent Application No. 4-407725 can be used, and these can be used alone or in combination.

The ink receiving layer of the ink jet recording material according to the present invention may contain various additives in addition to the binder. For example, as a surfactant, an anionic surfactant such as a long-chain alkyl benzene sulfonate, a long-chain, preferably a branched alkyl sulfosuccinate, a polyalkylene oxide of a long-chain, preferably a branched alkyl group-containing phenol. Nonionic surfactants such as ethers and polyalkylene oxide ethers of long-chain alkyl alcohols, JP-B-47-9303
Silane coupling agents such as γ-aminopropyltriethoxysilane, N-β (aminoethyl) γ-aminopropyltrimethoxysilane, such as fluorinated surfactants described in US Pat. No. 3,589,906 and the like; As a polymer hardener, an active halogen compound, a vinyl sulfone compound, an aziridine compound, an epoxy compound,
As hardeners and preservatives such as acryloyl compounds and isocyanate compounds, P-hydroxybenzoic acid ester compounds, benzisothiazolone compounds, isothiazolone compounds, etc. described or exemplified in JP-A-1-102551, JP-A-63-204251 Japanese Patent Laid-Open No. 1-266537, etc., and coloring pigments, coloring dyes, fluorescent whitening agents, etc. such as sodium hydroxymethanesulfonate, sodium P-toluenesulfinate, etc. as an anti-yellowing agent, and an ultraviolet absorber , A benzotriazole compound having a hydroxy-di-alkylphenyl group at the 2-position, an antioxidant, a polyhindered phenol compound described or exemplified in JP-A-1-105245, a pencil writing agent,
Starch granules, organic or inorganic particles such as barium sulfate and silicon dioxide having a particle diameter of 0.2 to 5 μm, organopolysiloxane compounds described or exemplified in Japanese Patent Publication No. 4-1337, caustic soda, carbonic acid as a pH adjusting agent Various additives such as soda, sulfuric acid, hydrochloric acid, phosphoric acid, and citric acid, octyl alcohol, and silicon-based antifoaming agents can be appropriately combined and contained.

[0044]

EXAMPLES The present invention will be described below in detail with reference to examples, but the contents of the present invention are not limited to the examples.

Example 1 Base papers A and B were produced as follows.

(Base Paper A) Hardwood Bleached Kraft Pulp 70
Length of pulp after beating a mixture of 30 parts of hardwood sulfite pulp and 30 parts of hardwood sulfite pulp (length-weighted average fiber measured according to Japan TAPPI paper pulp test method No. 52-89 "paper and pulp fiber length test method") 0.6)
After beating to a size of 3 mm and a Canadian Standard Freeness of 330 ml, 1 part by weight of cationized starch, 0.2 part by weight of anionized polyacrylamide, and an emulsion of alkyl ketene dimer (100 parts by weight of pulp) 0.4 parts by weight (as ketene dimer content), 0.2 parts by weight of epoxidized higher fatty acid amide, 0.4 parts by weight of polyamide epichlorohydrin resin, and an appropriate amount of optical brightener, blue dye, red dye and paper stock. A slurry was prepared. After that, the stock slurry is placed on a Fourdrinier paper machine running at 200 m / min to form a web while giving an appropriate turbulence, and a wet part of 15 kg / cm to 100 kg /
After performing the three-stage wet press in which the linear pressure is adjusted in the range of cm, the strip is treated with a smoothing roll, and in the subsequent drying part, the linear pressure is adjusted in the range of 30 kg / cm to 70 kg / cm. After press pressing, it was dried. Then, in the middle of drying, 25 g of a size press liquid consisting of 4 parts by weight of carboxy-modified polyvinyl alcohol, 0.05 part by weight of optical brightener, 0.002 part by weight of blue dye, 4 parts by weight of sodium chloride and 92 parts by weight of water. m ² size press, dried so that the final water content of the base paper is 8% by weight, and machine calendered at a linear pressure of 70 kg / cm to give a thickness of 150 μm and a density of 1.04 g. A base paper A having a density of / cm ³ was produced. JIS P 8125 in the papermaking direction of this base paper A
The Taber stiffness defined by the above was 10 gf · cm, and the film thickness unevenness index RPy was 170 mV.

(Base paper B) Using a stock slurry prepared in the same manner as the base paper A except that the amount of cationized starch added was 2 parts by weight relative to 100 parts by weight of pulp, the thickness was 16
A base paper B was produced by making paper in the same manner as the base paper A except that the paper had a thickness of 7 μm and a density of 1.02 g / cm ³ . The Taber stiffness defined by JIS P 8125 in the papermaking direction of the base paper B is 1
The film thickness unevenness index RPy was 165 mV at 5 gf · cm.

Next, after the surface of the base paper opposite to the side on which the image forming layer is provided (rear surface) is subjected to corona discharge treatment, the following resin compositions (R1) to (R4) are applied to the back surface of the base paper. Of four kinds of resin are melt-extruded at a resin temperature of 315 ° C. at a running speed of the base paper of 200 m / min, and the coating amount of each resin composition is 23 g / m ² , 26 g / m ² , 29 g / m ² . It was created. The surface of the back resin layer was processed into a matte surface using a cooling roll roughened by liquid honing.

(Resin Composition R1) High Density Polyethylene Resin (Density 0.967 g / cm ³ , MFR = 6.5 g / 10 min) 5
0 parts by weight and low density polyethylene resin (density 0.926 g
/ Cm ³ , MFR = 3.5 g / 10 minutes) 50 parts by weight, which is a resin composition simply mixed and used by adding it to a melt extruder as it is.

(Resin composition R2) High-density polyethylene resin (density 0.967 g / cm ³ , MFR = 6.8 g / 10 min) 6
5 parts by weight and low density polyethylene resin (density 0.926 g
/ Cm ³ , MFR = 3.5 g / 10 min) and 35 parts by weight of the resin composition were simply mixed, and the resin composition was used by simply adding it to the melt extruder.

(Resin Composition R3) High Density Polyethylene Resin (Density 0.967 g / cm ³ , MFR = 10 g / 10 min) 65
Parts by weight and low density polyethylene resin (density 0.926 g / c
m ³ and MFR = 0.6 g / 10 minutes) 35 parts by weight was a compound resin composition prepared by melting and mixing in advance using a melt extruder and used as pellets.

(Resin Composition R4) High Density Polyethylene Resin (Density 0.967 g / cm ³ , MFR = 15 g / 10 min) 70
Parts by weight and low-density polyethylene resin (density 0.924 g / c
m ³ and MFR = 0.6 g / 10 min) 30 parts by weight was a compound resin composition prepared by melting and mixing in advance using a melt extruder, and was used as the pellet.

Subsequently, the surface of the base paper was subjected to corona discharge treatment, and then a low density polyethylene resin (having a density of 0.92) was formed on the surface.
0 g / cm ³ , MFR = 8.5 g / 10 min) 47.5% by weight, hydrous aluminum oxide (against titanium dioxide to Al ₂ O ₃
50% by weight of anatase type titanium dioxide pigment surface-treated with 0.75% by weight) and 2.5% of zinc stearate.
20% by weight of a masterbatch of titanium dioxide pigment
Parts by weight, low-density polyethylene resin (density 0.920 g / c
m ^3, MFR = 4.5g / 10 min) 65 parts by weight of a high density polyethylene resin (density ^{0.970g / cm 3, MFR = 7.0g} /
10 minutes) The resin composition consisting of 15 parts by weight is added to the resin temperature 315
The running speed of the base paper is 20 so that the coating amount is 30 g / m ^{2 at} ℃.
Melt extrusion coated at 0 m / min. The melt extrusion coating of the front and back polyethylene resins was performed by a so-called tandem method in which extrusion coating was sequentially performed. At that time, the surface of the resin layer containing the titanium dioxide pigment of the resin-coated paper was processed into a glossy surface.

Further, after the front and back resin layers are processed and wound up, after the corona discharge treatment on the back resin layer surface of the resin-coated paper,
The following coating solution for the back layer was applied on-machine. As dry weight, colloidal silica: styrene latex =
The coating solution for the back layer, which is composed of 1: 1 and further contains 0.021 g / m ² of sodium polystyrene sulfonate and an appropriate amount of a coating aid and the like, has a latex content (calculated by solid weight) of 0.21.
The coating amount was g / m ² . In addition, in order to separately measure the infrared dichroic ratio (D value) of the back resin layer, a sample without a back layer was also prepared.

Further, after applying the back layer and before winding the resin-coated paper, the front side resin surface is subjected to corona discharge treatment, 1.2 g of lime-treated gelatin, low molecular weight gelatin (Nitta Gelatin Co., Ltd.). Manufactured by P-3226) 0.3 g,
0.3 g of a 10 wt% methanol solution of butyl paraoxybenzoate and a 5 wt% mixture of methanol and water of sulfosuccinic acid-2-ethylhexyl ester salt 0.45 g
Of which the total amount was adjusted to 100 g with water, was uniformly applied on-machine to give a gelatin coating amount of 0.06 g / m ² , to obtain a support for image materials.

Then, a blue-sensitive emulsion layer containing a yellow color-forming coupler, an intermediate layer containing a color mixing inhibitor, a green-sensitive emulsion layer containing a magenta color-forming coupler, and an ultraviolet absorber were formed on the undercoat layer of the support for image materials. The total amount of gelatin is 8g / g by providing an ultraviolet absorbing layer containing, a red-sensitive emulsion layer containing a cyan color forming coupler and a protective layer.
I made a color photographic paper that is m ² . Each color-sensitive emulsion layer contains silver chlorobromide equivalent to 0.6 g / m ² in terms of silver nitrate. In addition to gelatin necessary for the production, dispersion and film formation of silver halide, an appropriate amount of antifoggant and sensitizing dye. , Coating aids, hardeners, thickeners and appropriate amounts of filter dyes and the like. Next, the prepared color photographic paper is stored at 35 ° C. and normal humidity for 5 days, and after color development, 20 ° C., 20% RH and 20 ° C., 80% R
The state of curl of a color print having a size of 8.2 cm × 11.7 cm in H was evaluated. As the evaluation criteria, grade ◎: slightly negative curl (curl to the back layer side) and extremely flat, good curl physical properties, grade ○:
There is curl, but there is no problem in practical use, Δ: the curl is large, but it is at a practical limit, and x: the curl is extremely large, and there is a practical problem.

As a method for evaluating the cuttability of the image material, the roll-shaped color photographic paper having a width of 8.2 cm is used so that the blade width is 11.7 cm in the longitudinal direction with a precision print cutter. After cutting, the state of the cut surface was evaluated. As the evaluation criteria, ○: little or no beard, good cutting performance, △: slightly many beard, but practically no problem, ×: many beard and cutting performance Poor, and to some extent practically represent a problem.

Table 1 shows the results of the samples No. 1 to No. 24.

[0059]

[Table 1]

Note that (Note 1) to (Note 3) in Table 1 are as follows.

(Note 1) ○ indicates a sample according to the present invention.

(Note 2) The Taber stiffness (gf · cm) in the papermaking direction of the base paper measured by the method described in the text of the specification.

(Note 3) The infrared dichroic ratio (D value) of the back resin layer measured by the method described in the text of the specification is shown for the sample having no back layer.

Example 2 Instead of the base papers A and B of Example 1, the following base paper C,
Example 1 was repeated except that D and E were used, and the coating amount of the back resin layer was 26 g / m ² for each resin composition.

At this time, Samples No. 33 to No. 36 using the base paper E having a stiffness of more than 20 gf · cm were all roll-shaped color photographic paper stored at 35 ° C. and normal humidity for 5 days, and then wound. Curl caused by a very large. For this reason, a large amount of curl occurs in the wound direction even after the development processing, and the curl physical properties are insufficient.

(Base paper C) Fiber length of pulp after beating hardwood bleached kraft pulp (length-weighted average measured according to JAPAN TAPPPI paper pulp test method No. 52-89 "paper and pulp fiber length test method") (Displayed in fiber length) is 0.
After beating to a size of 67 mm and a Canadian Standard Freeness of 330 ml, chemicals were added in the same manner as Base Paper A except that the amount of cationized starch added was 3 parts by weight per 100 parts by weight of pulp. Using the stock slurry prepared above, the thickness is 150 μm and the density is 1.02.
A base paper C was produced by making paper in the same manner as the base paper A except for g / cm ³ . JIS P 8125 in the papermaking direction of this base paper C
The Taber stiffness defined by the above was 12 gf · cm, and the film thickness unevenness index RPy was 210 mV.

(Base paper D) Thickness is 174 μm and density is 1.
A base paper D was produced by making paper in the same manner as the base paper B except that the amount was 02 g / cm ³ . JIS P 81 in the papermaking direction of this base paper D
The Taber rigidity defined by 25 was 18 gf · cm, and the film thickness unevenness index RPy was 200 mV.

(Base paper E) The thickness is 200 μm and the density is 1.
A base paper D was produced in the same manner as the base paper C except that the amount was 00 g / cm ³ . The Taber stiffness specified by JIS P 8125 in the papermaking direction of the base paper is 24 gf · cm, and the uneven thickness index RP.
y was 210 mV.

Sample Nos. 25 to No. 3 based on the base papers C, D and E
The results of 2 are shown in Table 2.

[0070]

[Table 2]

Note that (Note 1) to (Note 3) in Table 2 have the same meanings as those in Table 1.

Example 3 Using the base paper B of Example 1, except that the back resin layer was made of the following resin compositions (R5) and (R6) so that the coating amount was only 23 g / m ^2. The same procedure as in 1 was performed.

(Resin Composition R5) High Density Polyethylene Resin (Density 0.967 g / cm ³ , MFR = 10 g / 10 min) 78
Parts by weight and low density polyethylene resin (density 0.926 g / c
m ³ and MFR = 0.6 g / 10 min) 22 parts by weight was a compound resin composition prepared by melting and mixing in advance using a melt extruder and used as pellets.

(Resin Composition R6) High Density Polyethylene Resin (Density 0.967 g / cm ³ , MFR = 15 g / 10 min) 85
Parts by weight and low density polyethylene resin (density 0.926 g / c
m ³ and MFR = 0.6 g / 10 minutes) 15 parts by weight, which was a compound resin composition prepared by previously melting and mixing with a melt extruder, and used as pellets.

The results of Samples No. 37 and No. 38 that were carried out are shown in Table 3, respectively.

[0076]

[Table 3]

Note that (Note 1) to (Note 3) in Table 3 have the same meanings as those in Table 1.

Example 4 The resin composition (R2) and (R4) were used for the back resin layer using the base paper B of Example 1 (Taber stiffness defined by JIS P 8125 in the papermaking direction is 15 gf · cm). The coating amount was 10 g / m ² , and the surface resin layer was the same resin composition as in Example 1 at 15 g / m ^2.
Three types of supports for image materials were obtained in the same manner as in Example 1 except that the coating amount was set. Then, instead of the multilayer silver halide color photographic constituent layers used in Example 1, the following inkjet image receiving layer was applied to prepare an inkjet image receiving material. Similarly, the back resin layer coverage is 8 g / m ²
When I tried to create a support so that
2) With the resin composition of (R4), a phenomenon occurs in which the film of the molten resin is cut off after leaving the die and before attaching to the base paper,
A support having a coating amount of the back resin layer of 8 g / m ² could not be prepared, and a support usable as an image material could not be obtained.

The ink jet image receiving layer is composed of a 10% by weight aqueous gelatin solution of alkali-processed gelatin having a molecular weight of 70,000.
g, 37.5 g of an 8 wt% aqueous solution of sodium carboxymethyl rose (etherification degree: 0.7 to 0.8, viscosity of a 2 wt% aqueous solution with a B type viscometer is 5 cp or less), an epoxy compound (Nagase 5 of NER-010) manufactured by Sangyo Co., Ltd.
0.3% by weight methanol solution, sulphosuccinic acid-2
A coating liquid consisting of 0.5 g of a 5% by weight mixture of ethylhexyl ester salt in methanol and water and 31.7 g of pure water was applied at a solid content of 3 g / cm ² to form a coating solution.

Sample No. in which the coating amount of the back resin was 10 g / m ² .
The evaluation results of No. 39 and No. 40 are shown in Table 4.

[0081]

[Table 4]

Note that (Note 1) to (Note 3) in Table 3 have the same meanings as those in Table 1.

As can be seen from the results of Examples 1 to 4, the infrared dichroic ratio of the backing resin layer was prepared using a base paper having a Taber stiffness in the papermaking direction of 12 gf · cm to 20 gf · cm. (D
Value) is 0.85 or less and the coating amount of the back resin layer is 1
0g / m ² ~27g image material support is / m ² (Sample No.1
6, 17, 19, 20, 22, 23, 26-28, 30
32 to 37 to 40), it is clearly understood that the image material has excellent curl properties and excellent cuttability and is an excellent support for image material. Furthermore, the infrared dichroic ratio (D
If the value) is 0.75 or less, the curl physical properties are more excellent, and if the infrared dichroic ratio (D value) is 0.65 or less, the curl physical properties are often more excellent. Recognize. In addition, a resin composition (R6) was used (Sample No.
In No. 38), the neck-in during the production of the resin-coated paper was large and the moldability was somewhat insufficient. Therefore, from the viewpoint of curl properties and molding processability, the infrared dichroic ratio (D value) of the back resin layer
Is preferably 0.75 or less, a support for an image material,
It is well understood that the support for image material having a ratio of 0.55 or more and 0.65 or less is particularly preferable.

[0084]

INDUSTRIAL APPLICABILITY According to the present invention, an excellent resin using paper as a substrate, which can provide an image material having good curl properties, good cuttability, and good molding processability and a print thereof, can be provided. It is possible to provide a support for coated paper type image materials.

Claims (5)

[Claims] 1. A paper having natural pulp as a main component is used as a base, and a paper base surface of the paper base on which an image forming layer is provided is a resin layer (A) capable of forming a film, and a paper base on the opposite side. Resin layer whose body surface is mainly composed of polyethylene resin (B)
In the support for image material coated with, the Taber stiffness defined by JIS P 8125 in the paper making direction of the paper base is 12 gf · cm to 20 gf · cm, and the infrared ray defined by the following of the resin layer (B) is used. The dichroic ratio (D value) is 0.85 or less, and the coating amount of the resin layer (B) is 10 g / m ^{2 to} 27 g /
A support for an image material, which is m ² . Infrared dichroic ratio (D value): The resin layer (B) coated on the side opposite to the side on which the image forming layer is provided without the back layer is coated on a paper substrate with an aqueous solution of sodium hypochlorite. detached from, the film peeled infrared absorption spectrum was measured with infrared light that is polarized by the polarizing plate, 720 cm ^-1 before and after the 730 cm ^-1 in the two front and rear derived from rocking vibration of CH ₂ of polyethylene molecules 720 cm in the infrared absorption peak
^-Calculate the peak intensity around ^-1 . This peak intensity is
Is the value of the obtained absorbance as the baseline the small dots and a line connecting the most absorbance in the 725cm ^-1 ~775cm ^-1 with small point of highest absorbance in the 675cm ^-1 ~725cm ^-1. At this time, the peak intensity A (=) around 720 cm ⁻¹ by infrared light polarized parallel to the running direction (longitudinal direction) at the time of melt extrusion and the infrared light polarized vertically The peak intensity A (+) around 720 cm ^-1 is determined, and the ratio of A (=) / A (+) is defined as the infrared dichroic ratio (D value). 2. The support for image materials according to claim 1, which has an infrared dichroic ratio (D value) of 0.75 or less. 3. The infrared dichroic ratio (D value) is 0.55 to 0.
The support for an image material according to claim 1, which is of 65. 4. The polyethylene-based resin of the resin layer (B) is
It contains low-density polyethylene-based resin and high-density polyethylene-based resin as main components, and the content ratio is low-density polyethylene-based resin: high-density polyethylene-based resin = 10 to 35:
90 to 65 (parts by weight), and the density of the low-density polyethylene resin is 0.935 g / cm ³ or less, JIS K
The melt flow rate specified by 6760 is 0.2 to 4.
5 g / 10 minutes, the density of the high-density polyethylene resin is 0.950 g / cm ³ or more, the melt flow rate defined by JIS K 6760 is 5-40 g / 10 minutes, and they are melted in advance. The support for image material according to claim 1, 2 or 3, which is a mixed compound resin composition. 5. The support for image materials according to claim 1, 2, 3 or 4, wherein the resin capable of forming a film in the resin layer (A) is a polyethylene resin.