JPS61210346A - Support for photographic printing paper - Google Patents

Abstract

PURPOSE:To utilize the metallic luster of a thin metallic film as brightness on the background of a desired positive image by placing the thin metallic film at a position in a support for photographic printing paper at which the film is seen from one side of the support on which a photographic emulsion layer is formed. CONSTITUTION:A support is produced by successively forming a thermoplastic resin layer 12, a thin metallic film 13, a base 14 and a thermoplastic resin layer 15 under a photographic emulsion layer 11 to be formed. The base may be any of transparent and opaque bodies. When the base is a transparent body, a thermoplastic resin layer 22, a transparent base 24, a thin metallic film 23 and a thermoplastic resin layer 25 may be successively formed under a photographic emulsion layer 21 to be formed. The especially preferred thin metallic film is a thin Al film. A support for photographic printing paper having remarkably enhanced brightness is obtd.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a support for photographic paper, and in particular to a support for water-resistant photographic paper that exhibits excellent shine.

[Background of the Invention] Photographic paper basically consists of a substrate, a silver halide emulsion layer (
It consists of a photographic emulsion layer) and a protective gelatin layer, but when a base paper made from pulp or the like is used as a base, it is necessary to prevent development processing chemicals from penetrating inside the base paper. A commonly used method is to coat both sides of a base paper with a polyolefin resin such as polyethylene to form a waterproof layer. Coating with this polyolefin resin is generally carried out by applying the polyolefin resin onto the surface of the base paper by melt extrusion. Note that an inorganic white pigment such as titanium dioxide is added to the surface polyolefin resin layer (the resin layer on the side where the photographic emulsion layer is provided) for the purpose of improving hiding. The fill lid is typically 7% to 15% by weight.

As mentioned above, the generally used support for photographic paper has a polyolefin resin layer containing an inorganic white pigment formed on one surface of the substrate (the surface on which the photographic emulsion layer is provided). On the other surface, a waterproof resin layer such as a simple polyolefin resin layer or a white pigment-containing polyolefin resin layer as described above is formed.

The photographic paper supports conventionally used as described above pose no particular problem in normal use.

However, depending on the purpose, a "brilliance J" may be required in the background of the positive image as it is formed on the surface of the photographic paper, and for such purposes, the photographic paper support having the above structure is not suitable. do not have.

[Object of the Invention] The main object of the present invention is to provide a new water-resistant photographic paper support that exhibits excellent brightness.

[Summary of the Invention] As an aspect of the invention, the present invention comprises a transparent substrate, a thermoplastic resin layer provided on the side of the substrate to which the photographic emulsion layer is attached, and a thermoplastic resin layer provided on the opposite side. Provided is a support for photographic paper comprising the following: at least one of the thermoplastic resin layers is provided on a substrate via a metal thin film layer.

In another aspect, the present invention includes an opaque substrate, a thermoplastic resin layer provided on the side of the substrate to which a photographic emulsion layer is attached,
and a thermoplastic resin layer provided on the opposite side thereof, the thermoplastic resin layer on the side to which the photographic emulsion layer is attached is provided on the substrate via a metal thin film layer. Provided is a support for photographic paper characterized by the following.

That is, the present invention provides a method for producing a positive image with the metallic luster exhibited by the metal thin film layer by arranging the metal thin film layer in a device comprising the side of the photographic paper support on which the photographic emulsion layer is provided. Its feature is that it can be used as a "reflection in the background".

[Effect of the Invention J The support for photographic paper of the present invention is a support for photographic paper with particularly markedly improved brightness, and the commercial value of photographic paper using this support is high.

[Detailed Description of the Invention 1 The photographic paper support of the present invention has the following basic configurations:
It has a structure consisting of a substrate having a two-gold thin film layer on at least one surface and thermoplastic resin layers provided on both surfaces of the substrate.

The substrate used in the present invention can be selected from known substrate materials for supports. Examples include polyester films such as polyethylene terephthalate and polybutylene terephthalate, cellulose triacetate films,
Transparent substrates such as polystyrene film, polypropylene film, and films of polyolefins such as polyethylene, base paper and cloth, and the aforementioned polymer films, polymer films with both sides of base paper or cloth coated with molten polyolefin, and polyolefin-coated paper, etc. Mention may be made of opaque substrates. The material for the above-mentioned base paper can be selected from known raw materials for supports. An example of this is paper made from natural pulp.

There are various types of paper such as paper made from synthetic pulp made of plastic materials such as polyethylene and polypropylene, paper made by mixing natural pulp and synthetic pulp, or paper made by combining natural pulp and synthetic pulp. .

Since the flatness of photographic paper is largely controlled by the flatness of the substrate, it is necessary to improve the flatness of the substrate. Therefore, for example, when using base paper made from short Fi&m valves as a substrate, it is preferable to use one that has been smoothed by thermal calendering or the like.

There is no particular limit to the thickness of the base, but it is between 30 and 300 mm.
JLm, preferably about 70 to 200 gm.

In the present invention, a metal thin film layer is provided on the surface of the substrate in order to enhance the brightness of the photographic paper. Examples of metals used for forming the metal thin film layer include Japanese Patent Application Laid-Open No. 50-1397
Metals mainly composed of aluminum as detailed in Publication No. 20, and JP-A-48-65927 and JP-A-48-6592.
Tellurium, molybdenum, boronium, cobalt, as described in Publications No. 8 and No. 50-2925,
Examples include metals and alloys such as zinc, copper, aluminum, iron, tin, vanadium, germanium, silver and silver emulsions, chromium, titanium, and the like. Among these, a particularly preferred metal thin film layer for the purposes of the present invention is an aluminum metal thin film layer.

The metal thin film layer may be formed by using a known method for forming a thin film, such as vacuum deposition, sputtering, ion blasting, or electrodeposition. Moreover, the metal thin film layer may be a single layer or a multilayer of two or more layers.

During the production of metal thin film layers - silicon oxide, silicon dioxide, silicon oxide, aluminum oxide, magnesium oxide, tantalum oxide, poron silicon oxide (
Oxidation of the metal thin film layer can be prevented by vacuum co-deposition of inorganic oxides such as borosilicate) and titanium oxide.

The thickness of the metal thin film layer is preferably in the range of 20 to 4000 angstroms, particularly preferably 50 to 50 angstroms.
The value is in the range of 0 angstroms.

Note that it is also possible to use a substrate on which a metal thin film layer is formed in advance, such as a metallized polyester film or metallized paper.

In the present invention, a thermoplastic resin coating layer is formed on both sides of a substrate having a metal thin film layer.

A substrate according to the present invention, a metal thin film layer provided on the substrate,
A typical embodiment of the structure of a support for photographic paper comprising thermoplastic resin layers provided on both sides of a substrate is schematically shown in the accompanying drawings.

FIG. 1 shows the structure of a support for photographic paper to which a photographic emulsion layer 11 is attached, and in order from the photographic emulsion layer 11, a thermoplastic resin layer 12, a metal thin film layer 13, a substrate 14, and a thermoplastic resin The structure of the support body formed by laminating the layer 15 is shown.

In the configuration shown in FIG. 1, the substrate may be transparent or opaque.

When the substrate is particularly transparent (when a polyethylene terephthalate sheet or the like is used as the substrate), as shown in FIG.
2. A configuration consisting of a transparent substrate 24, a metal thin film layer 23, and a thermoplastic resin layer 25 can also be adopted.

Examples of the thermoplastic resin in the present invention include α-olefin homopolymers such as polyethylene and polypropylene;
Mention may be made, for example, of copolymers of these α-olefins, polyolefins such as mixtures of these various polymers, polystyrene, and vinyl chloride. Among these, polyethylene is particularly preferred in terms of cost and properties.

The molecular weight of the thermoplastic resin is not particularly limited as long as extrusion coating is possible, and is usually 10,000 to 20,000.
It is in the range of 0. When polyethylene is used as the thermoplastic resin, the polyethylene layer to which the photographic emulsion layer is attached is generally formed using low-density polyethylene, but in order to improve the heat resistance of the substrate, It is preferable to use a blend of low density polyethylene and high density polyethylene.

The polyethylene layer on the back side is usually high density polyethylene,
Alternatively, it is formed using a blend of high-density polyethylene and low-density polyethylene.

The surface of the polyethylene layer on the side where the photographic emulsion layer is attached is 1
Molds can be formed during extrusion coating on surfaces, grains, matte surfaces, fine grain surfaces, etc.

Further, the polyethylene layer on the back side usually has a matte surface.

The thickness of the thermoplastic resin layer is usually about 10 to 1100 IL, preferably about 10 to 30 ILm.

In each of the above embodiments, the thermoplastic resin layer on the side to which the photographic emulsion layer is attached can be filled with an inorganic white pigment in a filling amount of 1 g/rn'' or less.

As the inorganic white pigment contained in the surface thermoplastic resin coating layer, those conventionally used for concealing photographic paper or those that have been proposed can be used. Examples include titanium dioxide, barium sulfate, calcium sulfate, barium chloride, calcium carbonate, lithopone, alumina white, zinc oxide, silica, antimony trioxide,
Examples include titanium phosphate. These can be used alone or in combination.

As the inorganic white pigment, titanium dioxide and zinc oxide are preferably used from the viewpoint of whiteness, dispersibility, stability, etc. Titanium dioxide is particularly preferred because it has a large hiding power.
Titanium dioxide may be of the rutile type or anatase type, and they may be used alone or in combination, and those made by the i&acid method, 11! Titanium dioxide, which may be made by a chemical method, can be treated with hydrated alumina,
Surface coating treated with inorganic substances such as hydrous silicon dioxide treatment or zinc oxide treatment, trimethylolmethane, trimethylolethane, trimethylolpropane, 2.4
-Dihydroxy-2-methylpentane or other organic substance surface coating treatment or polydimethylsiloxane or other siloxane treatment can be used as appropriate.

The loading amount of these am white pigments is Ig/r as described above.
If the loading is more than 1g/rrf'', the hiding power of the white pigment-containing resin layer will become too high, and the shine of the metal thin SS will be hidden by the resin layer, resulting in a bright support. Although it is possible to change the filling concentration of the inorganic white pigment depending on the thickness of the thermoplastic resin layer to be extrusion coated, it is usually preferably 3% or less.

The thermoplastic resin layer containing the inorganic white pigment is formed by, for example, dispersing the inorganic white pigment in a resin and applying the molten state to the surface of the substrate.

Metal soaps such as zinc stearate, aluminum stearate, and other surfactants can be used as dispersants to disperse the inorganic white pigment in the resin. Also,
It is also possible to use Ia-free colorants such as ultramarine and cobalt blue, organic colorants such as organic dyes and organic pigments, and fluorescent brighteners, which are preferable in order to increase the whiteness, that is, known photographic paper supports. Various additives used for forming the resin coating layer of the body can be arbitrarily used.

Each component for forming the thermoplastic resin coating layer can be kneaded and dispersed using a known mixing machine such as a two-roll mill, a Miki roll mill, a pressurized Negoo mixer, or a Banbury mixer.

Note that before extrusion coating the thermoplastic resin layer on the substrate, it is preferable to pre-treat the substrate by corona discharge treatment or the like in order to strengthen the adhesion between the substrate and the resin coating layer.

Further, the surface of the thermoplastic resin layer formed on the substrate surface on the side to which the photographic emulsion layer is attached may be subjected to surface treatment such as corona discharge treatment for the purpose of improving Wi adhesion with the photographic emulsion layer. Alternatively, an undercoat layer may be provided on the surface of the resin layer.

The support of the present invention can be used as a photographic paper by forming a photographic emulsion layer (silver/gelatin light-sensitive emulsion layer) thereon according to known techniques.

Next, Examples and Comparative Examples will be shown to further specifically illustrate the present invention.

[Example IJ A polyethylene terephthalate film with a thickness of 1100 JL was placed in a vacuum deposition apparatus as a substrate.

Vacuum deposition was performed under a vacuum degree of 10-'torr,
An aluminum vapor-deposited film having a thickness of 1000 angstroms was formed on the surface of the substrate.

After corona discharge treatment was applied to the surface of this aluminum vapor-deposited film, low-density polyethylene (MI=7g/10min,
Density 0.923g/cc) by extrusion coating,
A polyethylene resin layer was formed to have a thickness of 30 JLm.

Next, after corona discharge treatment is applied to the other surface cap 1 of the base, high-density polyethylene (MI=8 g/10 minutes,
A polyethylene resin layer with a thickness of 304 m was formed by extrusion coating with a density of 0.950 g/cc).

After corona discharge treatment was applied to the surface of a polyethylene resin layer formed from low-density polyethylene, a gelatin undercoat was applied, and a color photographic emulsion was coated thereon to produce color photographic paper. An image was printed on this photographic paper and developed to obtain a completed color print.

The brightness of this color print was visually judged. The results are shown in Table 1.

[Examples 2 to 4, Comparative Examples 1 to 2J An aluminum vapor deposition layer was formed in the same manner as in Example 1 on a polyethylene terephthalate film having a thickness of 100 gm as a substrate.

Low density polyethylene (MI=7g/10min, 'fE degree 0
．． 923g/cc) of anatase type titanium dioxide.
A resin composition filled as shown in the table was kneaded using a kneader. This resin composition was extrusion coated onto aluminum vapor deposited film E which had been subjected to corona discharge treatment to a thickness of 30 m to form a titanium dioxide-containing polyethylene resin layer. A polyethylene resin layer containing no white pigment was formed on the back surface of the substrate in the same manner as in Example 1.

Next, the surface of the titanium dioxide-containing polyethylene resin layer was subjected to corona discharge treatment, and then a color photographic emulsion was applied in the same manner as in Example 1 to produce color photographic paper. An image was printed on this photographic paper and developed to obtain a completed color print.

The brightness of this color print was visually judged and the results are shown in Table 1.

Table 1 (wt% Cg/rrfJ) (Brightness) Example 1
0[0] Yes 2 1[0,3J
Yes 3 2[0,6] Yes 4 3[0,9] Yes Comparative Example 1
5 [1, 5] None 2 10 [3, OJ
none

[Brief explanation of the drawing]

FIG. 1 and FIG. 2 are schematic diagrams showing an example of the structure of the support for photographic paper of the present invention. 11.21: Photographic emulsion layer 12.22: Thermoplastic resin layer (or inorganic white pigment-containing thermoplastic resin layer) 13.23: Metal thin film layer 14.24: Substrate 15.25: Thermoplastic resin layer Patent applicant Fuji Photo Film Co., Ltd. Representative Patent Attorney Yasushi Yanagawa Procedural Amendment 1.4 Display of 1985 Patent Application No. 52788 2 Title of Invention Support for Photographic Paper 3 Case of Person Making Amendment Relationship with Patent applicant name (520) Fuji Photo Film Co., Ltd. 4゜ Agent

Claims (1)

[Claims] 1. A support for photographic paper having a transparent substrate, a thermoplastic resin layer provided on the side of the substrate to which the photographic emulsion layer is attached, and a thermoplastic resin layer provided on the opposite side. 1. A support for photographic paper, characterized in that at least one of the thermoplastic resin layers is provided on a substrate via a metal thin film layer. 2. Photographic paper according to claim 1, characterized in that the thermoplastic resin layer on the side of the substrate on which the photographic emulsion layer is provided contains an inorganic white pigment in an amount of 1 g/m^2 or less support. 3. The support for photographic paper according to claim 1 or 2, wherein the metal thin film layer is an aluminum metal thin film layer. 4. A support for photographic paper having an opaque substrate, a thermoplastic resin layer provided on the side of the substrate to which the photographic emulsion layer is attached, and a thermoplastic resin layer provided on the opposite side thereof, wherein the photographic emulsion 1. A support for photographic paper, characterized in that a thermoplastic resin layer on the side to which the layer is attached is provided on a substrate via a metal thin film layer. 5. Photographic paper according to claim 4, characterized in that the thermoplastic resin layer on the side of the substrate on which the photographic emulsion layer is provided contains an inorganic white pigment in an amount of 1 g/m^2 or less support. 6. The support for photographic paper according to claim 4 or 5, wherein the metal thin film layer is an aluminum metal thin film layer.