JPH09146218A - Support for imaging materials - Google Patents

Abstract

(57) [Abstract] [PROBLEMS] To provide an image material having a high apparent glossiness and a good curl property and a print thereof, and yet to form a resin composition without forming pores on the surface of the resin-coated paper. To provide a support for a resin-coated paper type image material, which has good processability and can be produced at high speed and stably. In a support for an image material in which a base paper surface on the image forming layer side is coated with at least two resin layers, at least one of the resin layers has a density of 0.945 g / cm ³ or more,
MFR 9 to 30 g / 10 min Polyethylene resin (A) specific ratio and density less than 0.945 g / cm ³ , MFR 1 to 10 g /
Contains a specific proportion of polyethylene resin (B) for 10 minutes,
Further, the problem is solved by the total physical property value of the polyethylene resin component in the at least one layer being within a specific range.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention uses a paper mainly composed of natural pulp as a substrate, and one of the paper substrates (hereinafter sometimes abbreviated as base paper) on which an image forming layer is provided is the uppermost layer. The present invention relates to a support for an image material coated with at least two resin layers consisting of a resin and a lowermost layer, and an image material having a high appearance glossiness and a good curl property, and a print thereof, especially a silver halide photograph. Photographic paper and its prints (silver halide photographic paper prints may be abbreviated as photographic prints hereinafter) can be provided, and there are no crater-like pores and excellent smoothness without surface defects. Further, the present invention relates to a support for an image material which can be produced at high speed and stably.

[0002]

2. Description of the Related Art Usually, an image material is composed of a support for an image material and an image forming layer provided on the support. For example, a silver halide photographic material, an ink jet recording material, a heat transfer type thermal transfer recording image receiving material, a heat sensitive recording material and a light and heat sensitive recording material are a silver halide photographic constituent layer, an ink image receiving layer, a heat receiving layer and a heat sensitive recording layer, respectively. An image forming layer such as a transfer type thermal transfer recording image-receiving layer, a thermosensitive coloring layer, a photothermosensitive coloring layer, and an undercoat layer, a protective layer, etc. are coated, if necessary. In particular, the silver halide photographic constituting layer includes a silver halide photographic emulsion layer, a protective layer, an undercoat layer, an intermediate layer or an anti-color-mixing layer, an antihalation layer, or a filter layer, an ultraviolet absorbing layer, and a combination thereof. It is composed of For example, a single silver halide photographic material has a silver halide photographic emulsion layer and a protective layer provided on a photographic material support. Further, a multilayer silver halide color photographic material comprises an undercoat layer, a blue-sensitive silver halide photographic emulsion layer and an intermediate layer, a green-sensitive silver halide photographic emulsion layer and an ultraviolet absorbing layer, A silver halide photographic emulsion layer and a silver halide color photographic constituting layer such as a protective layer are provided in this order and are arranged in multiple layers.

Conventionally, a resin-coated paper type support having a base paper surface coated with a resin capable of forming a film for a support for an image material is well known. As a support for photographic materials for use in silver halide photographic materials, for example, JP-B-55-125
No. 84 discloses a technique for a support for a photographic material in which a base paper is coated with a resin capable of forming a film, preferably a polyolefin resin. US Patent 3,50
Japanese Patent No. 1,298 discloses a technique for a photographic material support in which both sides of a base paper are coated with a polyolefin resin. Further, since the rapid photographic development processing method of silver halide photographic materials was applied, supports for photographic materials in which both sides of a base paper were coated with a polyethylene resin have been mainly put to practical use for photographic printing paper. If necessary, the resin layer on the side on which one of the image forming layers is provided usually contains a titanium dioxide pigment for imparting sharpness.

Further, in US Pat. No. 4,774,224, the surface roughness of the resin coating is 7.5 microinch-AA.
There has been proposed a thermal transfer recording image receiving element having, as a support, the following resin-coated paper, particularly a polyethylene resin-coated paper in which the surface of a base paper is coated with a polyethylene resin. Further, Japanese Patent Application Laid-Open No. 63-307979 discloses a technique relating to an inkjet recording sheet having a resin-coated paper as a support.

However, a support for a resin-coated paper type image material in which the surface of the base paper, particularly the base paper mainly composed of natural pulp, on which the image forming layer is provided is coated with a resin layer is still serious. In reality, it has problems and has not yet obtained satisfactory results.

First, the side on which the image forming layer of the base paper is provided (hereinafter, the side on which the image forming layer is provided is the front side, the resin layer coated on the front side is the front resin layer, the opposite side is the back side, and the back side is the back side. Resin-coated paper for use as a support for image materials, in which at least the surface of the resin layer is sometimes referred to as a back resin layer) is coated with a resin layer containing at least a film-forming resin, particularly a resin layer containing a polyethylene resin. Using a melt extruder, the polyethylene resin composition is cast on the base paper to be cast into a film form from its slit die, coated, pressed between a pressure roll and a cooling roll, and separated from the roll after cooling. It is manufactured in a series of steps. At that time, in the case of producing a resin-coated paper for image materials for glossy use, as a cooling roll, a cooling roll having a mirror surface or a glossy surface or a finely rough surface described in Japanese Patent Publication No. 62-19732 and having an extremely smooth surface. Is used. Thus, the surface resin layer of the resin-coated paper is pressed against a cooling roll having an extremely smooth surface in its molten state so that it is processed into a surface having a smooth surface. Therefore, an image material using the resin-coated paper as a support and a print thereof. Then, it should be possible to obtain a product with a high glossy appearance. However,
With an image material and a print thereof using a resin-coated paper actually manufactured as a support, it was not possible to obtain a material having a sufficiently high glossiness in appearance. In particular, in the case of photographic printing paper using a resin-coated paper as a support, it was not possible to obtain a photographic printing paper and a photographic print having sufficiently high glossiness in appearance.

The inventors of the present invention have conducted various studies on the factors of the apparent glossiness of the image material and its print, and found that factors affecting the apparent glossiness include resin-coated paper as a support, an image forming layer, Although there are various factors such as an image forming method such as a development process, it has been found that the apparent glossiness of the image material and its print is greatly affected by the factors of the resin-coated paper as the support. Thus, the present inventors further conducted various studies on the factors of the resin-coated paper that affect the apparent glossiness. As a result, the apparent glossiness of the image material and the print thereof depended on the factors of the resin layer, and mainly the natural pulp. Factors such as the type and properties of the base paper used as components, such as the type of natural pulp, fiber length, stock slurry conditions such as paper additives to be included in stock slurry, papermaking speed, strain press, machine calender conditions Post-processing conditions such as papermaking conditions, size press, tab size press, etc.
It turned out that it depends on various factors such as the surface roughness of the base paper. Further, as the thickness of the surface resin layer of the resin-coated paper becomes thinner, particularly in the case of 31 μm or less, the image material having the resin-coated paper as a support and the apparent glossiness of the print become more remarkable. It turned out to drop. In particular, photographic materials for glossy use require a high degree of glossiness in photographic prints, and photographic materials with inferior glossiness in photographic prints are completely unsuitable for glossy use. There was a problem that the product had no commercial value.

Secondly, although resin-coated papers for image materials for glossy use are required to have a high degree of smoothness, the thickness of the surface resin layer is 40 μm or less particularly when a base resin is extrusion-coated with a molten resin. In some cases, or as the production speed of the resin-coated paper becomes faster, particularly at 200 m / min or more, crater-like pores are generated on the surface resin layer surface of the resin-coated paper for image material. When the crater-shaped pores are generated, there is a problem that the appearance glossiness of the image material and the print using the resin-coated paper as a support is further deteriorated and the commercial value is remarkably reduced.

In order to eliminate and improve various problems and other kinds of defects of the resin-coated paper type image material support as described above, JP-B-49-30446, JP-A-56-62248, JP-A-59-198451, JP-A-1-03435, etc. describe or exemplify a two-layer extrusion coating method such as a co-extrusion coating method and a sequential extrusion coating method, but they are not enough to solve the above-mentioned problems. It was sufficient, and particularly, it was extremely insufficient to improve or improve the appearance glossiness of the image material and the print using the resin-coated paper as a support.

For the purpose of improving the smoothness of resin-coated paper, a pulp having a specific fiber length distribution described in JP-A-58-68037 and a specific pulp described in JP-A-60-69649. Fiber length, width, thickness pulp, softwood pulp described in JP-A-61-35442, use of specific pulp such as low-viscosity pulp described in JP-A-63-173045, JP-A-58-37642 Japanese Patent Laid-Open Publication No. Sho.
Use of a base paper having specific physical property values such as a base paper having a surface roughness of not more than a specific value described in 63-291054, JP-A-60-12639
Thermal calendering of base paper described in JP-A No.
Paper making by a paper machine having an upper dewatering mechanism described in 84762, paper making by a fourdrinier double-layer paper making machine described in JP-A-63-204250, and wet paper web described in JP-A-64-20541. Techniques such as the use of a specific papermaking method such as a tenacity press treatment are disclosed, but they are not sufficient for solving the above-mentioned problems, and in particular, an image material having a resin-coated paper as a support and a print thereof. It was extremely insufficient to improve and improve the glossy appearance.

[0011]

Accordingly, a first object of the present invention is to use paper containing natural pulp as a main component as a substrate.
A resin-coated paper in which the base paper surface on the side on which one of the image forming layers is provided is coated with a resin layer, and using the resin-coated paper as a support, the apparent glossiness is remarkably high and the curling property is good. An excellent resin-coated paper-type image material support capable of providing various image materials and prints thereof, and having no crater-like pores on the surface of the resin layer and having good smoothness without surface defects. Is. The second object of the present invention is to coat the resin layer at a production rate of 150 m / min or more, particularly 200 m / min or more, and therefore, the productivity and economy are excellent, and the resin layer surface on the side where the image forming layer is provided is provided. It is an object of the present invention to provide an excellent support for a resin-coated paper type image material, which does not have crater-like pores and which has a good moldability of the resin composition and therefore can be produced at high speed and stably.

As a result of intensive studies to solve the above-mentioned problems, the inventors of the present invention have used paper having natural pulp as a main component as a substrate, and the paper substrate surface on one side where the image forming layer is provided is the lowermost layer. In a support for image material coated with at least two resin layers consisting of an upper layer, at least one of the resin layers has a density of 0.945 g / cm ³ or more and is defined by JIS K 6760. Polyethylene resin (A) 15-having a melt flow rate of 9-30 g / 10 minutes
45% by weight (as a weight ratio to the total polyethylene resin in the at least one layer) and a density of 0.945 g / cm ^3.
Less than 85% by weight of the polyethylene resin (B) having a melt flow rate of 1.0 to 10 g / 10 minutes specified by JIS K 6760 (weight based on the total polyethylene resin in the at least one layer). As a ratio, and the total density of the polyethylene resin components in the at least one layer is 0.920 to 0.93.
It has been found that the object of the present invention can be achieved by using a melt flow rate of 4 g / cm ³ and a melt flow rate specified by JIS K 6760 of 3.0 to 10 g / 10 minutes.

It has been found that the object of the present invention is remarkably achieved by applying at least two resin layer coatings in a sequential extrusion molten resin coating system. Moreover, it has been found that the object of the present invention is effectively achieved by disposing a specific resin layer satisfying the requirements of the present invention as the lowermost layer. Further, an object of the present invention is that, as the polyethylene-based resin (A), the melt flow rate defined by JIS K 6760 (hereinafter, the melt flow rate defined by JIS K 6760 may be simply abbreviated as MFR). It has been found that (1) is significantly achieved by using 10.5 to 20 g / 10 min. It has also been found that the object of the present invention is remarkably achieved by using a polyethylene resin (B) having an MFR of 2.0 to 9.0 g / 10 min. Further, the object of the present invention is to
The present invention has been found to be synergistically achieved by using, as the base paper, a stylus type three-dimensional surface roughness of 1.4 μm or less on the side where the image forming layer is provided, which has led to the present invention. .

The polyethylene resin (A) used in the practice of the present invention has a density of 0.945 g / cm ³ or more and an MFR of 9.0 to ³⁰ g / 10 min. Various densities, MFRs, molecular weights and molecular weight distributions can be used alone or as a mixture, and polyethylene-based resins produced by polymerization using a metal polymerization catalyst, for example, produced by polymerization using the Ziegler method, Phillips method, etc. Various materials such as polyethylene-based resins, polyethylene-based resins polymerized and produced using a metallocene polymerization catalyst, copolymers of ethylene and α-olefins such as propylene and butylene, carboxy-modified polyethylene resins, and mixtures thereof can be used.

The polyethylene resin (A) used in the practice of the present invention has a density of 0.945 to 0.962 g / in terms of overall performance such as appearance glossiness and curl of the image material and its print. cm ³ is preferred and 0.
Those of 950 to 0.960 g / cm ³ are particularly preferable. That is, the curl of the image material and the print using the resin-coated paper as a support is the point of the processability by the processing equipment when making a print from the image material, the appreciation of the finished print, and the ease of sticking to the album. Therefore, it is preferable that the image material and the print are slightly minus curl (curl to the opposite side of the image forming layer) and extremely flat, and if the density is too high, plus curl (curl to the image forming layer side).
Undesirably increases. On the other hand, the density is 0.945
If it is less than g / cm ³ , the effect of improving the appearance glossiness of the image material and its print and the effect of preventing crater-like pores cannot be obtained. As the polyethylene resin (A) used in the practice of the present invention, the appearance gloss of the image material and its print, the effect of preventing crater-like pores on the surface of the resin-coated paper, and the moldability of the resin composition. From the viewpoint of overall performance such as, those having an MFR of 9.0 to 30 g / 10 minutes are useful, but those having an MFR in the range of 10.5 to 20 g / 10 minutes are preferable. If the MFR is less than 9.0 g / 10 minutes, the effect of improving the apparent glossiness cannot be obtained, and the effect of preventing crater-like pores is insufficient. On the other hand, when the MFR is more than 30 g / 10 minutes, the molding processability of the resin composition is deteriorated, and the effect of improving the apparent glossiness is lost, which is a problem.

The polyethylene resin (B) used in the practice of the present invention has a density of less than 0.945 g / cm ³ and an MFR of 1.0 to 10 g / 10 min. Various densities, MFRs, molecular weights, and molecular weight distributions can be used alone or as a mixture, and polyethylene resins polymerized by a high pressure method, for example, using an autoclave type reactor, a tubular type reactor, etc. Various polyethylene-based resins having long-chain branching by a high-pressure production method under atmospheric pressure, polyethylene-based resins polymerized and produced using a metallocene polymerization catalyst, copolymers of ethylene and propylene, α-olefins such as butylene, and carboxy. Various materials such as modified polyethylene resin and mixtures thereof can be used.

The polyethylene resin (B) used in the practice of the present invention has a density of 0.925 g / cm ³ or less from the viewpoint of overall glossiness of the image material and its print, curl property and the like. It is preferably 0.921 g / cm ³ or less, and particularly preferably 0.921 g / cm ³ or less. As the polyethylene resin (B) used in the practice of the present invention, the glossiness of the visual appearance of the image material and its print, the effect of preventing crater-like pores on the surface of the resin-coated paper, the moldability of the resin composition. From the viewpoint of overall performance such as, those having an MFR of 1.0 to 10 g / 10 minutes are useful, but those having an MFR in the range of 2.0 to 9.0 g / 10 minutes are preferable. If the MFR is less than 1.0 g / 10 minutes, the effect of improving the apparent glossiness cannot be obtained, and the effect of preventing crater-like pores is insufficient. On the other hand, MFR is 10g / 10
If it is larger than this, the number of crater-shaped pores increases,
The effect of improving the apparent glossiness is extremely insufficient, and the molding processability of the resin composition is poor, which is a problem.

The content ratios of the polyethylene resin (A) and the polyethylene resin (B) in the resin layer used in the practice of the present invention are the glossiness and the curl of the image material and its print. From the viewpoint of total performance such as properties, the content ratio (as a weight ratio to the total polyethylene resin in the resin layer) is polyethylene resin (A) 1
5 to 45% by weight, and polyethylene resin (B) 85 to
The range of 15% by weight is useful, and the range of 20 to 40% by weight of the polyethylene resin (A) and the range of 80 to 60% by weight of the polyethylene resin (B) are preferable. If the content of the polyethylene resin (A) is too low and the content of the polyethylene resin (B) is too high, the effect of improving the appearance glossiness cannot be obtained, and the crater-like pores on the surface of the resin-coated paper cannot be obtained. Preventive effect becomes insufficient. On the other hand, if the content ratio of the polyethylene resin (A) is too high and the content ratio of the polyethylene resin (B) is too low, the curling properties of the image material and the print are deteriorated, and the moldability of the resin composition is poor. It is enough and it is a problem.

The total density and MFR of the polyethylene-based resin component in the resin layer containing the polyethylene-based resin (A) and the polyethylene-based resin (B) used in the practice of the present invention are as follows. From the viewpoint of overall performance such as the appearance glossiness and curl of the print,
A density of 0.920 to 0.934 g / cm ³ is useful, and an MFR of 3.0 to 10 g / 10 min is useful. If the density is too low, the effect of improving the apparent glossiness cannot be obtained, and if it is too high, the curling property deteriorates, which is a problem. Further, if the MFR is too low, the effect of improving the apparent glossiness cannot be obtained, and if it is too high, the molding processability of the resin composition is deteriorated, which is a problem.

The constitution and arrangement of at least two resin layers, which are the lowermost layer and the uppermost layer, used in the practice of the present invention are advantageous in terms of the present invention, in particular, the glossiness of the image material and its print. From the viewpoint of the improvement effect of 1., the lowermost resin layer is preferably a resin layer satisfying the requirements of the present invention, and all the resin layers are particularly preferably resin layers satisfying the requirements of the present invention. Further, in the resin layer, in addition to the polyethylene-based resins (A) and (B), other polyethylene-based resins, polypropylene, polybutene, polypentene, etc. may be used as long as the effects of the present invention are not impaired. A homopolymer, a copolymer composed of two or more α-olefins such as an ethylene-butylene copolymer, and a polyester resin may be contained.

The polyethylene-based resin (A) and the polyethylene-based resin (B) used in the practice of the present invention, and other resins which may be contained as necessary, are used by simply adding them to a melt extruder. However, it is preferable to use a compound resin prepared by melting and mixing these resins in advance, in terms of molding processability and film uniformity, and preventing uneven resin solidification called resin gel. Is preferred. Various methods can be used for preparing the compound resin by previously melting and mixing.
For example, using a kneading extruder, a heating roll kneader, a Banbury mixer, a pressure kneader, or the like, a predetermined amount of the polyethylene resin (A) and the polyethylene resin (B), and other resins used in combination as necessary. A method in which additives such as an antioxidant, a lubricant, etc. are added and melted and mixed, and then the mixture is pelletized is advantageously used.

The back side of the base paper of the image material support of the present invention is preferably coated with a resin capable of forming a film. As those film-forming resins,
Thermoplastic resins such as polyolefin resins, polycarbonate resins, polyester resins, and polyamide resins are preferred. Among them, polyolefin resins are more preferred from the viewpoint of melt extrusion coating properties, and polyethylene resins are particularly preferred. Further, it may be coated with an electron beam curing resin described or exemplified in JP-B-60-17104.

The resin layer on the front side of the image material support in the present invention may have a multilayer structure of two layers or more, but the two-layer structure is effective for achieving the object of the present invention. preferable. Further, the support for an image material in the present invention is produced by a so-called melt extrusion coating method in which a heated and melted resin composition is cast and coated on a running base paper. At that time, a so-called coextrusion coating method may be used in which the upper resin layer on the front side of the support for image materials and the resin layer of the lowermost layer are simultaneously extrusion-coated, or the so-called coextrusion coating method may be used. A so-called sequential extrusion coating method may be used in which the resin layers are sequentially melt-extruded and coated at separate stations. From the viewpoint of synergistically obtaining the effect of the present invention, in particular, the effect of improving the appearance glossiness of the image material and its print and the effect of preventing crater-like pores on the surface resin surface, the sequential extrusion coating method is preferable.
Further, as the successive extrusion coating method, a so-called tandem extrusion coating method in which the lowermost resin layer and the upper resin layer are successively melt-extruded by on-machine is particularly preferable.

Further, in the melt extrusion coating, the slit die is preferably a flat die such as a T die, an L die and a fishtail die, and the slit opening diameter is preferably 0.1 mm to 2 mm. Further, the type of the multilayer co-extrusion die may be any type such as a feed block type, a multi-manifold type, and a multi-slot type. Further, the temperature of the molten film is preferably 280 ° C. to 340 ° C., in which case there may be a difference in temperature between the upper layer and the lower layer. For example, the temperature of the upper layer may be lower than that of the lower layer by 5 to 10 ° C. to improve the releasability of the resin layer from the cooling roll.

The coating thickness of the surface resin layer of the support for image materials in the present invention is usefully in the range of 8 to 100 μm, preferably in the range of 12 to 60 μm, and 18 to 40.
The range of μm is particularly preferred. Further, as the thickness of the lowermost resin layer, from the viewpoint of the effect of improving the appearance glossiness of the image material and the effect of preventing crater-like pores on the surface resin surface, 45% of the total resin layer thickness on the surface side is used. The above thickness is preferable. Further, the base paper surface on the back side is preferably covered with a back resin layer containing a resin capable of forming a film as a main component, and the resin is preferably a polyethylene resin, and the coating thickness is a resin layer on the front side, In particular, it is preferable to appropriately set the curl balance, and the range of 8 to 100 μm is generally useful, but the range of 12 to 60 μm is preferable.

In carrying out the present invention, it is preferable that the base paper is subjected to an activation treatment such as a corona discharge treatment or a flame treatment before the base paper is coated with the front and back resin compositions. 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. In addition, the front and back resin layers are sequentially, preferably continuously, extrusion-coated, and are preferably coated on the base paper by a so-called tandem extrusion coating method. May be coated with a multilayer structure. 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.

Various additives can be contained in the front resin layer of the support for image materials of the present invention and, if necessary, in the back resin layer. For the purpose of improving the whiteness of the support and the sharpness of the image, JP-B-60-3430, JP-B-63-11655, JP-B1-38291, JP-B1-382
It is preferable to incorporate a titanium dioxide pigment described or exemplified in Japanese Patent Application Laid-Open No. 92, JP-A No. 1-105245 and the like. In addition to titanium dioxide, zinc oxide, white pigments such as talc and calcium carbonate, fatty acid amides such as stearic acid amide and arachidic acid amide, zinc stearate, calcium stearate, aluminum stearate, magnesium stearate, zinc palmitate, Fatty acid metal salts such as zinc myristate and calcium palmitate
1-105245 publication or exemplified hindered phenol, hindered amine, phosphorus-based, various antioxidants such as sulfur-based, cobalt blue, ultramarine blue, cerian blue, blue-based pigments and dyes such as phthalocyanine blue, cobalt violet, Various additives such as magenta pigments and dyes such as fast violet and manganese violet, fluorescent brightening agents and ultraviolet absorbers described or exemplified in JP-A-2-254440, and the like can be contained in an appropriate combination. The additives are preferably contained as a resin masterbatch or compound. Further, from the viewpoint of effectively improving the sharpness of prints, it is preferable that a white pigment such as titanium oxide and other additives are contained in a higher concentration in the uppermost resin layer than the lower resin layer.

The base paper used in the practice of the present invention is preferably natural pulp paper containing normal natural pulp as a main component. Further, a mixed paper made of synthetic pulp and synthetic fiber containing natural pulp as a main component may be used. Such natural pulp is described or exemplified in JP-A-58-37642, JP-A-60-67940, JP-A-60-69649, JP-A-61-35442 and the like. It is advantageous to use such appropriately selected natural pulp. 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. Softwood pulp, hardwood pulp,
Wood pulp, which is a mixed pulp of softwood and hardwood, is advantageously used, and various kinds of kraft pulp, sulfite pulp, soda pulp and the like can be used.

The base paper containing natural pulp as a main component used in the practice of the present invention may contain various additives when preparing a stock slurry. As a sizing agent, a fatty acid metal salt or fatty acid, an 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 or 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, carbonate calcium,
Fixing agents such as titanium oxide, water-soluble aluminum salts such as aluminum chloride and vanadium sulfate, etc., pH adjusting agents such as caustic soda, sodium carbonate, sulfuric acid, etc.
It is advantageous to appropriately combine a color pigment, a color dye, a fluorescent whitening agent and the like described or exemplified in JP-A-204251 and JP-A 1-266537.

A composition comprising various water-soluble polymers or hydrophilic colloids or latexes, antistatic agents, and additives in or on the base paper containing natural pulp as a main component used in the practice of the present invention. Can be contained or applied by a size press, a tab size press, or a coating such as blade coating or air knife coating. As a water-soluble polymer or a hydrophilic colloid, starch-based polymers described or exemplified in JP-A-1-266537, polyvinyl alcohol-based polymers,
Gelatin-based polymer, polyacrylamide-based polymer,
Emulsions, latexes such as cellulosic polymers, petroleum resin emulsions, at least ethylene and acrylic acid (or methacrylic acid) described or exemplified in JP-A-55-4027 and JP-A-1-180538 Emulsion or latex of copolymer, styrene-butadiene type, styrene-acrylic type, vinyl acetate-acrylic type, ethylene-vinyl acetate type, butadiene-methylmethacrylate type copolymer and emulsion of carboxy-modified copolymer thereof Alternatively, as antistatic agent such as latex, sodium chloride,
Clay and kaolin as pigments such as alkali metal salts such as potassium chloride, alkaline earth metal salts such as calcium chloride and barium chloride, colloidal metal oxides such as colloidal silica and organic antistatic agents such as polystyrene sulfonate. , Calcium carbonate, talc, barium sulfate, titanium oxide, etc. as a pH adjusting agent, hydrochloric acid, phosphoric acid, citric acid,
Advantageously, caustic soda and the like, as well as other additives such as the above-mentioned coloring pigments, coloring dyes and optical brighteners, are appropriately combined and contained.

The thickness of the base paper used for carrying out the present invention is not particularly limited, but the basis weight is 30 to 250 g /
Those of m ² are preferred.

Further, the base paper containing natural pulp as a main component used in the practice of the present invention remarkably improves the appearance glossiness of the image material and its print, and has crater-like pores on the surface resin surface. From the viewpoint of effectively preventing the generation, the center plane average roughness in the papermaking direction at the cutoff value of 0.8 mm measured using a stylus type three-dimensional surface roughness meter on the front side of the base paper is 1.4 μm. The following are preferred, those of 1.3 μm or less are more preferred, those of 1.2 μm or less are more preferred, and those of 1.1 μm or less are particularly preferred.

The center surface average roughness SRa at a cutoff value of 0.8 mm measured by using a stylus type three-dimensional surface roughness meter referred to in the present specification is defined by the equation 1.

[0034]

(Equation 1)

In Equation 1, Wx represents the length of the sample surface area in the X-axis direction (papermaking direction), Wy represents the length of the sample surface area in the Y-axis direction (direction perpendicular to the papermaking direction), and Sa Represents the area of the sample surface area.

Specifically, as a stylus type three-dimensional surface roughness meter and a three-dimensional roughness analyzer, SE-produced by Kosaka Laboratory Ltd.
Using 3AK type machine and SPA-11 type machine, cutoff value 0.8mm, Wx = 20mm, Wy = 8mm, therefore Sa = 1
It can be obtained under the condition of 60 mm ² . In the data processing in the X-axis direction, sampling was performed at 500 points, and
17 or more lines are scanned in the axial direction.

The base paper having the center surface average roughness SRa of 1.4 μm or less is specifically, by using the following methods, preferably two or more of the following methods, more preferably three or more in combination. It was clarified by the study of the present inventors that it can be obtained by using it.

(1) As the natural pulp to be used, a large amount of a sulfite pulp having a smoothness, preferably a hardwood sulfite pulp, is used. Specifically, JP 60
The hardwood sulfite pulp described or exemplified in JP-A-67940 is used in an amount of 30% by weight or more, preferably 50% by weight or more.

(2) A pressure press is used during the drying of the wet paper. Specifically, the wet paper web is subjected to a multi-stage pressure press as described or exemplified in JP-A-3-29945.

(3) Various water-soluble polymers, hydrophilic colloids or polymer latices are contained or coated in or on the base paper. Specifically, various water-soluble polymers or hydrophilic colloids or polymer latices in or on the base paper are applied as a solid coating amount by size press, tab size press, blade coating, air knife coating, etc. .2
It is preferable that g / m ² or more is contained or coated.

(4) After making the base paper, at least two or more series of calendar treatments are applied to the base paper using a machine calender, a super calender, a thermal calender, or the like. Specifically, for example, after subjecting the base paper to machine calendering and / or thermal machine calendering as the first series of calendering, and then further machine calendering as necessary as the second series of calendering and thereafter. It is preferable to perform the thermal soft calender treatment described or exemplified in JP-A-4-110939.

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 as described or exemplified in Japanese Patent Application Laid-Open No. Hei. Further, on the back resin layer surface of the image material support of the present invention, after performing an activation treatment such as a corona discharge treatment or a flame treatment, various back coat layers are applied for antistatic and the like. Can be. Further, the back coat layer has a Japanese Patent Publication No. 52-18020, Japanese Patent Publication No. 57-9059, Japanese Patent Publication No. 57-53940, Japanese Patent Publication No. 58-56859, and Japanese Patent Laid-Open No.
9-214849, JP-A-58-184144 and the like or exemplified inorganic antistatic agents, organic antistatic agents, hydrophilic binders, latexes, curing agents, pigments, surfactants and the like in appropriate combination It can be done.

The support for an image material 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, reverse photographic material, The silver salt diffusion transfer method can be used for various purposes such as 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 may contain a color coupler to provide a multilayer silver halide color photographic constituting layer. Further, a photographic component layer for a silver salt diffusion transfer method can be provided. As a binder for these photographic constituent layers, in addition to ordinary gelatin, hydrophilic high-molecular substances such as polyvinylpyrrolidone, polyvinyl alcohol and polysaccharide sulfate compounds can be used. 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. , Hardener, formalin, vinyl sulfone compound, aziridine compound, etc., coating aid, alkylbenzene sulfonate, sulfosuccinic acid ester salt, etc., anti-fouling agent, dialkyl hydroquinone compound, etc., fluorescent brightening agent, sharpness improvement Dye, antistatic agent, pH adjusting agent,
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, Photo Technology 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 support for image material in the present invention can be used as a support for various heat transfer type thermal transfer recording image receiving materials by coating various heat transfer type thermal transfer recording image receiving layers. Synthetic resins used for the heat transfer type thermal transfer recording image receiving layer include ester bonds such as polyester resin, polyacrylate resin, polycarbonate resin, polyvinyl acetate resin, polyvinyl butyral resin, styrene acrylate resin, and vinyl toluene acrylate resin. Resin having urethane bond such as polyurethane resin, resin having amide bond such as polyamide resin, resin having urea bond such as urea resin, other polycaprolactam resin, styrene resin, polyvinyl chloride resin, vinyl chloride -Vinyl acetate copolymer resin, polyacrylonitrile resin and the like. In addition to these resins,
Mixtures or copolymers of these can also be used.

In the heat transfer type thermal transfer recording image receiving layer according to the present invention, a releasing agent, a pigment or the like may be added in addition to the above synthetic resin. As the release agent, polyethylene wax, amide wax, solid wax such as Teflon powder,
Fluorine-based, phosphate ester-based surfactants, silicone oils and the like can be mentioned. Among these release agents, silicone oil is most preferred. As the above silicone oil,
An oily substance can be used, but a curable one is preferable. 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. The thickness of the image receiving layer is preferably 0.5 to 20 μm, more preferably 2 to 10 μm.

The image material support of the present invention may be coated with various ink image-receiving layers and used as various ink jet recording material supports. Various binders can be contained in the ink image receiving layer for the purpose of improving the drying property of the ink, the sharpness of the image, and the like. 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, starches such as oxidized starch, cationized starch and etherified starch, cellulose derivatives such as carboxymethyl cellulose and hydroxyethyl cellulose, polyvinylpyrrolidone, polyvinylpyridinium halide, polyacryl Acid soda, 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, synthetic polymers such as polyethyleneimine Conjugated diene copolymer latex such as styrene / butadiene copolymer, methyl methacrylate / butadiene copolymer, 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 3-2490 6, 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 image-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 Publications, color pigments or colored pigments or dyes described in JP-A 1-266537 or the like, a fluorescent whitening agent,
Sodium hydroxymethanesulfonate, sodium P-toluenesulfinate, etc., as an anti-yellowing agent, a benzotriazole compound having a hydroxy-di-alkylphenyl group at the 2-position as an ultraviolet absorber, an antioxidant, etc. As a pencil writing agent such as the polyhindered phenol compounds described or exemplified in 105245, organic or inorganic fine particles such as starch particles, barium sulfate, and silicon dioxide having a particle size of 0.2 to 5 μm, JP-B No. 4-1337. An organopolysiloxane compound described or exemplified in the publications,
As the pH adjusting agent, various additives such as caustic soda, sodium carbonate, sulfuric acid, hydrochloric acid, phosphoric acid, citric acid, octyl alcohol, and silicon-based defoaming agent can be appropriately combined and contained.

[0049]

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.

Examples 1 to 13 and Comparative Examples 1 to 6 Fiber length of pulp after beating a mixed pulp consisting of 70% by weight of hardwood bleached kraft pulp and 30% by weight of hardwood bleached sulfite pulp (JAPAN TAPPI paper pulp test method No. .52-89 (indicated by length-weighted average fiber length measured in accordance with "paper and pulp fiber length test method") was 0.60 mm, and then cation was added to 100 parts by weight of pulp. Starch 3 parts by weight, anionized polyacrylamide 0.2 parts by weight, alkylketene dimer emulsion (as ketene dimer content) 0.4 parts by weight, polyamide epichlorohydrin resin 0.4 parts by weight and a suitable amount of optical brightener, A blue dye and a red dye were added to prepare a stock slurry. Then, 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 is used for 15 to 10 minutes.
After performing a three-stage wet press in which the linear pressure was adjusted in the range of 0 kg / cm, it was treated with a smoothing roll, and in the subsequent drying part, a two-stage pressure was adjusted in the range of 30 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 of absolutely dry water, machine calendered at a linear pressure of 130 kg / cm,
Center surface average roughness SRa of basis weight 170 g / m ² is 1.30 μm
A base paper for a support for an image material that is

Next, after the base paper surface (rear surface) on the side opposite to the side on which the image forming layer is coated is subjected to corona discharge treatment, a low density polyethylene resin (density 0.924 g / cm ³ , MFR
= 1 g / 10 min) 30 parts by weight and high-density polyethylene resin (density 0.967 g / cm ³ , MFR = 15 g / 10 min) 70 parts by weight of a compound resin composition at a resin temperature of 320 ° C. and a resin thickness of 25 μm. The base paper was melt-extrusion coated at a running speed of 200 m / min. At this time, as the cooling roll, a roll having a center line average roughness Ra of 1.0 μm defined by JIS K0601 on the back resin layer surface was used. The cooling roll used was a cooling roll roughened by a liquid honing method and operated at a cooling water temperature of 12 ° C.

Then, after the surface of the base paper was subjected to corona discharge treatment, a polyethylene resin composition shown in Table 3 having a thickness of 15 μm as a lower resin layer and a resin layer having a thickness of 15 μm as an upper layer were formed on the surface. The polyethylene resin composition described in 3 is used at a resin temperature of 315 ° C. and the running speed of the base paper is 2
Using a melt extruder at a station of 00 m / min, a lower layer and then an upper layer in that order, melt-extrusion coating was sequentially performed at a linear pressure of 40 kg / cm on a mirror-like cooling roll and a press roll. The titanium dioxide pigment master batch was contained in the upper layer so that the titanium dioxide pigment concentration was 13% by weight. Titanium dioxide pigment masterbatch
Polyethylene resin composition 4 used as the upper layer in Table 3
7.5% by weight, 50% by weight of anatase type titanium dioxide pigment surface-treated with hydrous aluminum oxide (0.75% by weight as Al ₂ O ₃ content based on titanium dioxide) and 2.5% by weight of zinc stearate, and Tetrakis [methylene-3
(3,5-di-tert-butyl-4-hydroxyphenyl) propionate] methane 150 ppm. The melt extrusion coating of the front and back resin compositions was performed by a so-called tandem method in which the back resin layer, the lower front resin layer and the upper front resin layer were sequentially extrusion coated.

Further, after the corona discharge treatment on the back resin layer surface of the resin-coated paper, the following back coating liquid was applied on-machine. As dry weight, colloidal silica: styrene
Acrylate copolymer latex = 1: 1
Further, a back coat coating liquid containing 0.021 g / m ² of sodium polystyrene sulfonate and an appropriate amount of a coating aid and the like is applied at a coating amount of 0.21 g / m ² as a latex content (calculated by solid weight). A support for image material was obtained.

Molding processability of the polyethylene resin composition for the surface resin layer at the time of producing the resin-coated paper type image material support and the surface resin layer surface of the obtained image material support As a method for evaluating the degree of crater-shaped pores generated, the following method was evaluated.

As a method for evaluating the moldability of the polyethylene resin composition for the surface resin layer at the time of manufacturing the support for image materials, the lateral length of the resin coating portion on the surface is measured to determine the degree of neck-in. In addition to the evaluation, the degree of streaking of the molten resin film, the presence or absence of film breakage depending on the degree of drawdown property, and the molding processability such as flow instability due to surging or draw resonance were evaluated comprehensively. As the evaluation criteria, ◯: extremely good, □: good, Δ: slightly bad but practically no problem, x: bad and practically problematic to some extent.

As a method for evaluating the degree of crater-like pores generated on the surface resin surface of the support for image materials, the surface resin is measured according to the method for measuring the center surface average roughness SRa defined in the present specification. 1 μm from the surface roughness diagram (Z-direction magnification: 2000 times) obtained by drawing the 16-line surface roughness diagram with the XY plotter while measuring the center surface average roughness SRa of the layer surface.
The above-mentioned depressions were used as crater-shaped pores for the assay.
As the evaluation criteria, ○: crater-shaped pores are not generated at all or □, crater-shaped pores are slightly generated, △: crater-shaped pores are generated, but it is a practical problem. Indicates that there are not many, there are many pores on the crater, and there are some problems in practical use.

Next, the following methods were used to evaluate the glossiness and curl properties of the photographic prints using the resin-coated paper as a support.

After applying the back coat coating solution and before winding the resin-coated paper, the resin surface on the front side was subjected to corona discharge treatment, 0.75 g of lime-treated gelatin, low molecular weight gelatin (manufactured by Nitta Gelatin Co., Ltd.). , P-3226) 0.75
g, 0.3 g of a 10 wt% methanol solution of butyl paraoxybenzoate and a 5 wt% mixed solution of methanol and water of sulfosuccinic acid-2-ethylhexyl ester salt 0.4
A subbing coating solution containing 5 g and adjusted to 100 g with water was uniformly applied on-machine to a gelatin coating amount of 0.06 g / m ² to obtain a support for an image material having an undercoat layer. Obtained.

Next, a blue-sensitive emulsion layer containing a yellow color-forming coupler, an intermediate layer containing a color-mixing inhibitor, and a green-sensitive emulsion layer containing a magenta color-forming coupler are provided in this order on the undercoat layer of the support for image materials. , A UV-absorbing layer containing a UV-absorbing agent, a red-sensitive emulsion layer containing a cyan color coupler and a protective layer for multilayer coating E
A color photographic paper having a total amount of gelatin of 7 g / m ² was prepared by coating with a bar. Each color-sensitive emulsion layer is silver nitrate 0.6 g /
It comprises silver chlorobromide corresponding to m ^2, and more generation of silver halide, other gelatin required dispersion and film formation, an appropriate amount of antifoggants, sensitizing dyes, coating aids, hardening agents, thickening It contains an agent and an appropriate amount of filter dye. Next, the color photographic paper prepared was stored at 35 ° C. and normal humidity for 5 days, and after color development, the curl state of a color print of 8.2 cm × 11.7 cm at 20 ° C. and 50% RH was set. evaluated. The evaluation criteria are: ○; slightly negative curl (curl to back coat layer side) and extremely flat, and very good curl physical properties, □; slightly positive curl (curl to emulsion layer side), but curl physical property Good, Δ: There is a plus curl, but there is no problem in practical use, and ×: A large plus curl, there is a problem in practical use to some extent.

The color photographic paper thus prepared was stored at 35 ° C. under normal humidity for 5 days, and then the group photograph was baked, developed, bleached / fixed, washed with water, and dried to prepare a photographic print. Separately, baking samples of white solid (unexposed) and black solid (black coloring) were prepared. In addition, a series of processes of exposure, development, and drying were performed by an automatic printer and an automatic developing machine. The color development processing is the color development (1
Min 30 sec) → bleach-fix (1 min 30 sec) → stable (1 min 30)
Second) → drying procedure.

With respect to the obtained group photograph, white solid and black solid photographic prints, the visual glossiness of the photographic prints was visually evaluated comprehensively by 10 monitors.

The evaluation criteria for the appearance glossiness of photographic prints are as follows. A: Very high glossiness in appearance. 〜 To ○: Appearance of glossiness is considerably high. ◯: The glossy appearance is high. □: The glossy appearance is slightly high. Δ: Appearance of gloss is slightly low, but practical use is possible. X: The appearance has a low glossiness, and there is a practical problem.

The obtained results are shown in Table 3.

[0064]

[Table 1]

[0065]

[Table 2]

[0066]

[Table 3]

[Note 1] in Table 2 and (Note 2) in Table 3 are as follows. (Note 1) It has the same meaning as the type of polyethylene resin in Table 1. (Note 2) It has the same meaning as the type of compound resin in Table 2.

As is clear from Table 3, the base paper is coated with at least two resin layers consisting of the lowermost layer and the uppermost layer, and at least one of the resin layers has a density of 0.945 g / cm ³ or more. And the MFR is 9 to 30 g / 10 minutes, and the polyethylene resin (A) is 15 to 45% by weight (as a weight ratio to the total polyethylene resin in the at least one layer) and the density is less than 0.945 g / cm ^3. And the MFR is 1.
0 to 10 g / 10 minutes polyethylene resin (B) 85
15% by weight (as a weight ratio with respect to the total polyethylene resin in the at least one layer), and the total density of the polyethylene resin components in the at least one layer is 0.920 to 0.934 g / cm ^3. And MF
The image material support (Examples 1 to 13) of the present invention in which R is 3.0 to 10 g / 10 minutes can provide a photographic print having a high appearance glossiness and a good curl property.
Further, it is well understood that it is an excellent support for image materials, in which crater-like pores are not generated, and further, the moldability of the resin composition at the time of production is good, and therefore stable production is possible.

From the viewpoint of the effect of improving the glossy appearance of photographic prints and overall performance, the density is 0.945 g / cm ³
As the polyethylene resin (A) described above, MFR
Is preferably in the range of 10.5 to 20 g / 10 minutes (Example 3 and Examples 11 to 12), and the density is 0.945 g / c.
As the polyethylene-based resin (B) having a size of less than m ³ , MF
It can be seen that those having R in the range of 3.0 to 8 g / 10 minutes (Example 3 and Examples 7 to 8) are preferable. Further, the density is 0.
The content ratio of the polyethylene-based resin (A) of 945 g / cm ³ or more is preferably in the range of 20 to 40% by weight (as a weight ratio to the total polyethylene-based resin in the at least one layer) (Examples 2 to 4). ) Is well understood.

On the other hand, the polyethylene resin (A) having a density of 0.945 g / cm ³ or more has an MFR of 9 to 30 g /
When a material not in the range of 10 minutes is used (Comparative Examples 5 to 6),
When the polyethylene resin (B) having a density of less than 0.945 g / cm ³ has a MFR that is not in the range of 1.0 to 10 g / 10 minutes (Comparative Examples 3 to 4) or a density of 0.9
When the content of the polyethylene resin (A) of 45 g / cm ³ or more is not within the range of 15 to 45% by weight (as a weight ratio to the total polyethylene resin in the at least one layer) (Comparative Examples 1 and 2) The support for image materials other than the present invention has a problem that the glossiness and curl physical properties of the photographic print are poor, crater-like pores are often generated, and the moldability of the resin composition is poor. I understand that there is.

Examples 14 to 17 and Comparative Example 7 In Examples 14 and 16 to 17, instead of the resin composition for the upper layer and the lower layer used in Example 3, the polyethylene resin or polyethylene described in Table 4 was used. It carried out like Example 3 except using a resin composition. The melt extrusion coating was performed by a method (sequential method) of sequentially performing melt extrusion coating in separate stations in the order of the lower layer and then the upper layer. Further, a titanium dioxide pigment masterbatch was contained in the upper layer so that the titanium dioxide pigment concentration was 13% by weight. The titanium dioxide pigment masterbatch was prepared in the same manner as in Example 3 except that the polyethylene resin or the polyethylene resin composition used in the upper layer shown in Table 4 was used.
Prepared in the same manner as

Example 15 is carried out in the same manner as in Example 3 except that the method of melt extrusion coating using a two-layer simultaneous extruder is used instead of the sequential melt extrusion coating method of Example 3 (coextrusion method). did.
Further, in Comparative Example 7, a single layer of the same resin composition was melt-extrusion coated (single system) instead of the sequential melt-extrusion coating system of Example 3, and the upper layer of Example 14 was used as a resin composition. The same procedure as in Example 3 was carried out except that the resin composition used was used and the coating thickness of the resin layer was 30 μm.

The results obtained are shown in Table 4.

[0074]

[Table 4]

[Note 3] in Table 4 is as follows. (Note 3) It has the same meaning as the type of polyethylene resin in Table 1 or the type of compound resin in Table 2.

As is clear from Table 4, the base paper is coated with at least two resin layers consisting of the lowermost layer and the uppermost layer, and at least one of the resin layers is a specific resin layer satisfying the requirements of the present invention. The support for image materials (Examples 14 to 17) in the present invention, which has a high appearance glossiness, can provide a photographic print with good curl, and has no crater-like pores. It can be clearly seen that the resin composition at the time of production has excellent moldability, and therefore can be stably produced, and is an excellent support for image materials.

From the viewpoint of the effect of improving the glossiness of the appearance of photographic prints and the overall performance, the method of coating at least two resin layers is as follows: The lower layer and the upper layer are sequentially melt-extruded and coated at separate stations. It can be clearly seen that the method is preferable (Example 14 and Examples 16 to 17). In addition, as the constitution or arrangement of the specific resin layer satisfying the requirements of the present invention, the arrangement in which the lowermost layer is the specific resin layer satisfying the requirements of the present invention (Examples 14 and 16)
It is well understood that the arrangement (Example 14) in which all layers are resin layers satisfying the requirements of the invention is particularly preferable.

On the other hand, even when a resin layer satisfying the requirements of the invention is used, a single layer of the resin layer is melt-extruded and coated by a single method. ), The glossiness of the photographic print is extremely low, and it is well understood that there are many crater-like pores and there is a problem.

Examples 18 to 29 Instead of the base paper used in Example 3, pulp was beaten to give the fiber lengths shown in Table 5, and machine calendered at the linear pressure shown in Table 5, Further, the procedure was performed in the same manner as in Example 3 except that the base paper produced by the heat calendering treatment under the condition of the temperature of 200 ° C. with the combinations shown in Table 5 was used.

The results obtained are shown in Table 5.

[0081]

[Table 5]

(Note 4) to (Note 6) in Table 5 are as follows.

(Note 4) Pulp after beating JAPA
N TAPPI Paper Pulp Test Method No. 52-89 The length-weighted average fiber length measured according to "Paper and pulp fiber length test method". The measurement is made by Kajaani FS-100.
I went with a mold machine.

(Note 5) "None" means that thermal soft calendering is not performed.

(Note 6) Indicates the center surface average roughness SRa (μm) of the base paper surface on the side on which the image forming layer is provided, measured by the method specified in this specification.

From the results shown in Table 5, the base paper used in the practice of the present invention was selected from the viewpoint of the glossiness of the appearance of photographic prints and the effect of improving the crater-like pores, and the central surface on the side where the image forming layer is provided. The average roughness SRa is preferably 1.4 μm or less, more preferably 1.3 μm or less,
It can be seen that those of 1.2 μm or less are more preferable, and those of 1.1 μm or less are particularly preferable.

Examples 30 to 41 Instead of the polyethylene resin composition for the upper and lower layers used in Example 3, the resin compositions shown in Table 6 were used, and the resin layers for the upper and lower layers shown in Table 6 were used. Was carried out in the same manner as in Example 3 except that the thickness of was set to that shown in Table 6. Also,
A titanium dioxide pigment masterbatch was contained in the upper layer so that the titanium dioxide pigment concentration was 15% by weight. A titanium dioxide pigment masterbatch was prepared in the same manner as in Example 3 except that the polyethylene resin used in the upper layer shown in Table 6 was used.

The obtained results are shown in Table 6.

[0089]

[Table 6]

[Note 7] in Table 6 is as follows. (Note 7) It has the same meaning as the type of compound resin in Table 2.

As is apparent from Table 6, the support for image material in the invention (Examples) in which the base paper was coated with at least two specific resin layers satisfying the requirements of the invention consisting of the lowermost layer and the uppermost layer (Examples) 30-41) has a high glossy appearance,
In addition, it is possible to provide a photographic print with good curl property, without the generation of crater-like pores, and with good moldability of the resin composition at the time of production, and therefore stable production, which is an excellent image material. It can be seen that it is a support. Further, it is well understood that the effect of the present invention becomes large when the resin layer containing the preferred polyethylene resin in the present invention is arranged as the lowermost layer (Examples 30 to 38 and Example 40).

Examples 42 to 45 A stock slurry was prepared in the same manner as in Example 3 except that 100% by weight of hardwood bleached kraft pulp or 100% by weight of hardwood bleached sulfite pulp was used in place of the mixed pulp used in Example 3. Was prepared. Then, using a fourdrinier paper machine having a plurality of heads, a stock slurry prepared by using 100% by weight of hardwood kraft pulp as a lower layer was dried to 119 g / m ² and 100% by weight of hardwood sulfite pulp as an upper layer. used except that 2-layer papermaking such that 51 g / m ² absolute dry paper stock slurry prepared by, center plane average roughness SRa of the basis weight of 170 g / m ² in the same manner as in example 3 is 1.12μm Was produced. Then, it carried out like Example 14-17 except using the base paper.

The obtained results are shown in Table 7.

[0094]

[Table 7]

As is clear from the comparison between Tables 7 and 4, from the viewpoint of the appearance glossiness of photographic prints and the effect of improving crater-like pores, the base paper used in the practice of the present invention has two layers. It can be clearly seen that the base paper having the above-mentioned multilayer structure is preferable.

Examples 46 to 47 and Comparative Examples 8 to 9 Instead of the silver halide color photographic constituent layers on the image material support used in Examples 3, 7 and Comparative Examples 1 and 7, An ink jet recording material was prepared by coating the following ink image receiving layer. As a result, an ink jet recording material having the image material support of the invention (those of Examples 3 and 7) (Example 46 corresponding to the support,
Example 47) had a high gloss appearance and good curl properties, while an ink jet recording material having a support for image materials (comparative examples 1 and 7) other than the present invention. (Comparative Examples 8 and 9 corresponding to the support)
Was inferior in glossiness in appearance and had a problem.

The ink image-receiving layer contained 30 g of a 10% by weight aqueous gelatin solution of an alkali-processed gelatin having a molecular weight of 70,000, sodium carboxymethyl cellulose (etherification degree of 0.7 to
0.8, viscosity of 2 wt% aqueous solution with B type viscometer is 5 cp
37.5 g of an 8 wt% aqueous solution of the following) and 5 wt% of an epoxy compound (Ner-010 manufactured by Nagase & Co., Ltd.)
Formed by applying a coating liquid consisting of 0.3 g of a methanol solution, 0.5 g of a 5 wt% mixed solution of sulfosuccinic acid-2-ethylhexyl ester salt in methanol and water, and 31.7 g of pure water at a solid content of 7 g / m ² Was done.

Examples 48 to 49 and Comparative Examples 9 to 10 Instead of the silver halide color photographic constituent layers on the support for image materials used in Examples 3, 7 and Comparative Examples 1 and 7, The following heat transfer type thermal transfer recording image receiving layer was applied to prepare a heat transfer type thermal transfer recording image receiving material. As a result, the thermal transfer type thermal transfer recording image-receiving materials (Examples 48 and 49 corresponding to the support) having the image material support (Examples 3 and 7) of the present invention were visually observed. However, the thermal transfer type thermal transfer recording image receiving material (corresponding to the support, Comparative Examples 9 and 10) had a problem in that the glossy appearance was inferior.

The heat transfer type thermal transfer recording image receiving layer is composed of a saturated polyester resin (TP-220: manufactured by Nippon Gosei Co., Ltd.) 10
5 parts by weight, amino-modified silicone (KF-393: manufactured by Shin-Etsu Chemical Co., Ltd.) 0.5 parts by weight, and a coating composition comprising 30 parts by weight of solvent (xylene / methyl ethyl ketone = 1/1), using a wire bar, the solid content is 5 g. It was formed by applying / m ² minutes.

[0100]

According to the present invention, the glossy appearance is high,
In addition, it is possible to provide an image material having a good curl property and a print thereof, and yet, there is no generation of crater-like pores, and further, the molding processability of the resin composition is good, therefore, a high-speed and stable production of a natural pulp is possible. It is possible to provide an excellent resin-coated support for paper-type image materials, which uses paper as a main component as a substrate.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI Technical display area D21H 19/20 D21H 1/34 D

Claims (8)

[Claims] 1. An image in which a paper containing natural pulp as a main component is used as a substrate, and the paper substrate side on which one of the image forming layers is provided is coated with at least two resin layers including a lowermost layer and an uppermost layer. In the support for materials, at least one of the resin layers has a density of 0.945 g / cm ³ or more, and JI
The melt flow rate specified by SK 6760 is 9 to.
Polyethylene resin (A) 15 to 45, which is 30 g / 10 minutes
% By weight (as a weight ratio with respect to the total polyethylene resin in the at least one layer) and density of less than 0.945 g / cm ³ , and a melt flow rate defined by JIS K 6760 of 1.0 to 10 g / 10 The total density of the polyethylene resin component in the at least one layer is 85 to 55% by weight (as a weight ratio to the total polyethylene resin in the at least one layer). Is 0.920 to 0.934
A support for an image material, which has a melt flow rate of 3.0 to 10 g / 10 minutes and a g / cm ³ of JIS K 6760. 2. The support for image material according to claim 1, wherein the at least one layer is the lowermost layer. 3. The JIS K of polyethylene resin (A)
6760 has a melt flow rate of 12 to 2
The support for image materials according to claim 1 or 2, which has a weight of 0 g / 10 minutes. 4. The JIS K of polyethylene resin (B)
6760 has a melt flow rate of 2.0 to
The support for image materials according to claim 1, 2 or 3, which has a weight of 9.0 g / 10 minutes. 5. The titanium dioxide pigment in the uppermost layer on the image forming layer side is 7% by weight or more (as a ratio to the weight of the uppermost layer).
The support for an image material according to claim 1, which is contained. 6. At least two of a bottom layer and a top layer
The support for image material according to claim 1, 2, 3, 4, or 5, wherein the resin layer coating of the layers is performed by a sequential extrusion molten resin coating method. 7. The substrate paper has a cut-off value of 0.8 mm, which is measured using a stylus-type three-dimensional surface roughness meter on the side where the image forming layer is provided, and has a center plane average roughness of 1. The image material support according to claim 1, which has a thickness of 4 μm or less. 8. The support for an image material according to claim 1, wherein the substrate paper has a layer structure of two or more layers.