JPH0365948A - Photographic base - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a photographic support using paper as a substrate (hereinafter, the paper serving as the substrate is referred to as base paper), both sides of which are coated with polyolefin resin. Specifically, the present invention relates to a photographic support in which the whiteness of the resin surface on which an image is formed is improved. More specifically, the present invention uses a fluorescent agent to reduce the yellowish tendency caused by titanium oxide, especially rutile titanium oxide, contained in a high concentration in the resin layer on the image forming side of a resin-coated paper-type photographic support. The present invention relates to a photographic support whose whiteness is significantly reduced and improved by adding it to a resin layer.

From another perspective, the present invention relates to a resin-coated paper-type photographic support containing a high concentration of highly dispersed titanium oxide in the image-forming resin layer.

Furthermore, from another perspective, the present invention relates to a resin-coated paper-type photographic support that is coated with a resin composition that prevents staining of the die lip portion that occurs during extrusion processing and is free from streak-like surface damage.

The present invention relates to a resin-coated paper-type photographic support coated with a resin composition and having good surface properties.

[Prior art]

Recently, as photographic supports other than film-sensitive materials,
The mainstream is a waterproof support made of a base paper with high sizing property coated on both sides with a polyolefin resin, particularly a polyethylene resin. The reason for this is that the resin-coated waterproof support meets the demands for automation and speeding up the development process of photosensitive materials, especially photographic paper.

The polyolefin resin layer on the front side of the waterproof support, on which the image is formed, contains a titanium oxide pigment mainly for image sharpness and other photographic performance requirements, but the addition of titanium oxide to the resin layer Three major problems arose in connection with this.

The first problem is that titanium oxide pigments are not dispersed sufficiently well in polyolefins.

Since the dispersion of titanium oxide is not perfect, the resolution is insufficient when used as photographic paper.As described in Japanese Patent Publication No. 61-26650, there is a method using titanium oxide whose particle surface has been treated with alcohol amine. , Special public school 5th year
No. 8-43734, JP-A-58-14830, JP-A No. 17
433, No. 58542, and No. 75151, methods of treating particle surfaces with di- or tetrahydric alcohols have been proposed.

However, when using the proposed method, during resin coating processing, when melt extruding the resin composition into a film from a slit die, stains (referred to as die lip stains) tend to occur on the tip of the die lip, and are difficult to clean up. In particular, this die lip stain tends to grow larger and larger as the melt extrusion time passes.

If this die lip stain occurs during melt extrusion coating, streaks may appear in the vertical direction on the surface of the photographic support produced as is, or streak-like unevenness may occur due to uneven coating amount. However, sometimes dirt adheres to the film and is coated, causing foreign matter to appear. As a result, the surface quality of the produced polyolefin resin-coated paper was significantly impaired, making it completely unsuitable and without commercial value as a photographic support that requires excellent surface quality. The effect also becomes meaningless.

The second problem is that the titanium oxide pigment has a yellowish tinge, so in No. 11, the whiteness of the white background of the photographic image is insufficient.

In particular, in the case of color photographic paper, which has been widely used in recent years, faithful color reproduction and vivid colors are required, so we need to consider the support.

A clear white color with no visible coloration is required.

! In addition, while technology related to titanium oxide pigments and resins has progressed, there has been a strong demand for improved sharpness of color images and black and white images. As titanium oxide pigment concentrations tend to increase more and more, techniques for improving visual whiteness are becoming increasingly important.

Conventionally, several techniques are known for improving the whiteness of a resin layer containing titanium oxide on the image forming side of a resin-coated paper-type photographic support.

U.S. Patent No. 3,501,298 discloses that in addition to titanium oxide in the resin layer, ultramarine, which is a blue-tinted inorganic pigment, cobalt blue, and copal phosphate oxide, which is a reddish inorganic pigment (Ferrr
o Ra5pber manufactured by Co1ors Corp.
ry V-6260), containing quinacridone red which is a reddish inorganic pigment, and Uvi tex
It is known that OB (trade name manufactured by CIBAGE IGY) contains a fluorescent brightener having a (alkyl-substituted benzoxacylyl)thiophene structure. JP-A-53-19021 describes ultramarine, which is a bluish inorganic pigment;
It has been disclosed that cosmetic ultramarine powders called Daiichi Binku DP-1 and Daiichi Violet DV-1 (both manufactured by Daiichi Kasei Kogyo Bukuro), which are reddish inorganic pigments, are contained. Furthermore, Japanese Patent Publication No. 56-51336 discloses the inclusion of a fluorescent brightener having a bis(alkyl-substituted benzoxacylyl)7talene structure in a resin layer. Furthermore, as a comparative example, a technique is disclosed in which a quinacridone-based reddish organic pigment is contained in a resin.

However, each of these techniques has drawbacks.

That is, inorganic! We have developed a new technology that improves visual whiteness by neutralizing the yellowish tendency caused by high concentrations of titanium oxide pigments by adding organic coloring pigments. Because it makes it white,
The problem is that the brightness decreases and clear whiteness cannot be obtained.

! Furthermore, in the case of inorganic color pigments, they generally tend to contain a large amount of water, and thus bring a large amount of water into the resin composition. If the water content in the resin composition increases, a problem arises in that the resin film is more likely to crack due to water vapor blowing out during melt extrusion coating. Furthermore, ultramarine and cobalt-based inorganic coloring pigments deteriorate the heat resistance of the resin due to their chemical activity, and degraded resin compositions adhere to and accumulate at the die lip opening of the extrusion coating machine, causing icicle-like formation. Encourage the tendency to grow. When this icicle-like adhered deposit is generated, there is a problem in that it causes streak-like scratches on the resin film and significantly impairs the commercial value of the resin-coated paper-type photographic support. Regarding the technique of improving whiteness by adding a fluorescent brightener such as bis(alkyl-substituted benzoxacylyl)thiophene into a resin composition, a photographic material using the coated paper as a support is coated with an acid hardening fixer. When processed, there was a problem in that the whiteness did not improve, but instead turned yellow.

Further, as a result of the inventor's studies, it has been found that a fluorescent agent, particularly a bis(benzoxasilyl)7talene fluorescent agent or a bis(benzooxacylyl)stilbene fluorescent agent, and titanium oxide,
In particular, when a polyolefin resin composition containing an inorganic-treated titanium oxide pigment is melt-extruded onto a substrate from a slit die in the form of a film, the occurrence of die lip stains is promoted.
Furthermore, it has been found that when the resin composition contains an inorganic or organic coloring pigment or coloring dye, particularly a blue coloring pigment or coloring dye, there is a problem in that the occurrence of die lip staining is further promoted. did.

The third problem is that of die lip stains.

Even without organic surface treatment or combined use with a fluorescent agent, the inclusion of a titanium oxide pigment in polyethylene at a high concentration itself causes die lip staining, which is a major operational problem.

As a way to solve such problems,
No. 734 discloses that the physical property value n of a resin composition measured at 200° C. 10008-1 is 5 or less.

However, if the physical property value n is set to 5 or less according to this method, the separation between the cooling roll and the resin surface tends to be incomplete during the production of resin-coated paper, and there is a problem in that fine avatar-like scratches occur especially when processed at high speed.

[Purpose of the invention]

Therefore, the purpose of the present invention is to ensure high sharpness as a photographic paper with high titanium oxide dispersibility, high whiteness, no unevenness due to streaky thickness irregularities that occur during processing, and no apter-like scratches. It is an object of the present invention to provide a resin-coated paper-type photographic support free of oxidation.

[#g of the present invention]

The object of the present invention is to provide a photographic support made of paper as a substrate and coated with polyolefin on both sides, on the side on which an image is to be provided a polyethylene resin layer containing a) a fluorescent agent and a) organic surface-treated titanium oxide. This can be achieved by using a photographic support which has the following characteristics and whose physical property value n of the resin composition determined by the method described below is 4.0 or less at 200° C. and a shear rate of 1000/sec.

The physical property value n referred to in this specification is defined as follows.

Using a stock cylinder part 8 with a diameter (di) of 10 mm and a diameter meter, these parts are kept at a constant temperature and the stock cylinder 8 is filled with the resin composition.

By lowering the descending beam 1 at a constant speed, pressure is applied to the resin composition through the load cell 2, plunger 3, and spacer 4 that is in close contact with the inner wall of the stock cylinder, and the resin composition is extruded at a constant shear rate by the capillary 9, which generates pressure at a constant shear rate. A load cell detects the resistance force.

This measurement was performed using capillary length (L) of 10 mm and 20 mm.
mm.

The measurements were carried out on three types of 30 mm capillaries, and the obtained measurement values were plotted against L/D (Figure 3), and the line from the intersection of the L/D axis and the straight line found by the least squares method connecting them to the origin was The value expressed in units of interval = iL/D is defined as the physical property value n.

The physical property value n is the physical property value described above, but when it comes to the physical property value n, it is
PHYSIC8: Vol 28, A5: 1
May 957 issue: pages 624-627.

As a result of intensive studies, the inventors of the present invention found that it is a polyethylene resin composition containing a) a fluorescent agent and a) organic surface-treated titanium oxide, and its physical property value n measured at 200°C and a shear rate of 1000/sec is 4. A photographic support made by melt-extrusion coating a resin composition of . It has been found that there is no occurrence of uneven coating amount and no occurrence of apter-like scratches.

Individual elements of the structure of the present invention are already known,
Although it was possible to predict to some extent the effects of each combination, the degree of influence on items other than the original purpose of each technology was completely unknown. The effect on apex-like scratches was first clarified through studies conducted by the present inventors.

As the fluorescent agent used in the present invention, a fluorescent agent of general formula [I] or [■] is preferably used.

(In the formula, B1, R2, R5, R4, R5, R6, R7 and 'EL4 each represent a hydrogen atom or an organic residue.

)Specifically...[XII] The content of these fluorescent agents in the resin composition should be determined based on overall properties such as whiteness, resin processability, heat resistance, bleed-out resistance, and weather resistance. From this point of view, 0.1 vq/lr? ~50-
The range is particularly preferably 0.5η/lt? ~
10119/rn” range.

However, as a method for incorporating the fluorescent agent in the resin composition in the present invention, a master patch of titanium oxide pigment is used!
Or when producing a compound, do you also include a fluorescent agent and create a master rose consisting of a titanium oxide pigment, a fluorescent agent, a polyolefin resin, and a dispersant, such as a fatty acid metal salt? Or create a compound and incorporate it into the resin composition.
2, it's clear. In addition, a master patch of a fluorescent agent in which a fluorescent agent premixed with a low molecular weight polyolefin that has a softening point lower than that of the main polyolefin resin and is solid at room temperature or/and a dispersant, such as a fatty acid metal salt, is dispersed in the main polyolefin. can be prepared and incorporated into the resin composition.

The organic surface-treated titanium oxide used in the present invention includes:
Alkanolamine-treated titanium oxide, low molecular weight polyhydric alcohol-treated titanium oxide, and the like are preferably used.

Specifically, alkanolamines such as ethanolamine, butanolamine, jetanolamine, N-methylethanolamine, triethanolamine, N,N-dibutylpropanolamine, ethylene glycol, propylene gellicol, 1° 3-dihydroxybutane, 1
．． 4-dihydroxybutane, pentamethylene glycol, 2.5-dihydroxyhexane, 2.4-dihydroxy-2-methylpentane, heptamethylene glycol,
Dodecamethylene glycol, glycerin, trimethylolethane, trimethylolpropane, 2,4-dihydroxy-3-hydroxymethylpentane, 1,2゜6-
2-4 such as hexandriol, 2,2-bis(hydroxymethyl)-3-butanol, pentaerythritol, etc.
Examples include titanium oxide whose surface has been treated with a high molecular weight alcohol.

As for the processing amount, for alkanolamines,
The preferred range is 0.1 to 5% by weight, and for low molecular weight polyhydric alcohols, 0.1 to 1.5% by weight.

The crystal form of titanium oxide may be anatase type or rutile type, but rutile type is more preferable in consideration of sharpness when used as photographic paper.

However, if the content of titanium oxide pigment in the resin composition is less than 5% by weight, the sharpness and resolving power will decrease as a photographic support, which is a problem, and if it exceeds 4% by weight, the fluidity will decrease. and undesirable.

A range of 7 to 30% by weight is preferred, and a range of 9 to 25% by weight is particularly preferred. A method for incorporating titanium oxide pigment into the resin composition of a photographic support is to prepare a so-called masterbatch in which titanium dioxide is contained in a polyolefin at a certain concentration in advance, and then dilute it with a diluent resin to the desired ratio. Usually, they are used as a mixture, or a so-called compound is prepared by containing a titanium dioxide pigment in a polyolefin in a desired composition ratio from the beginning. To create these masterbatches and compounds, Banbury mixers, kneaders, kneading extruders, two-roll kneaders, three-roll kneaders, etc. are usually used.
Banbury mixers and mixed-wire extruders are advantageously used. Further, two or more types of these various crosstalk devices may be used in combination.

Specific examples of masterbatch manufacturing methods include methods described or exemplified in, for example, JP-A-60-11841, JP-A-60-75832, and JP-A-60-181131.

In carrying out the present invention, the shear rate at 200°C is 1000/sec.
As a method for reducing the physical property value n of the resin composition to 4 or less in c., it is relatively easy to find a combination of resins in which the physical property value n of each individual resin is 4 or less. I can do it.

The pulp constituting the base paper used in the practice of the present invention includes Japanese Patent Application Laid-open Nos. 58-37642 and 60-6794.
No. 0, JP-A-60-69649, JP-A-61-354
Although it is advantageous to use appropriately selected natural pulp as described or exemplified in No. 42, synthetic pulp or synthetic fibers other than natural pulp may be used if necessary. Natural pulp is subjected to conventional bleaching treatments such as chlorine, hypochlorite, and chlorine dioxide bleaching, as well as alkali extraction or alkali treatment and, if necessary, oxidative bleaching treatment with hydrogen peroxide, oxygen, etc., and combination treatments thereof. Wood pulps such as treated softwood pulp, hardwood pulp, and softwood hardwood mixed pulp are advantageously used, and various pulps such as kraft pulp, sulfide pulp, and soda pulp can also be used.

The base paper used in the practice of the present invention can contain various sizing agents, polymer compounds, and additives at the time of preparing the paper stock slurry.

Sizing agents that can be advantageously contained in the base paper used in the present invention include fatty acid metal salts and/or fatty acids, alkyl ketene dimers, alkenyl or alkyl succinic anhydrides, and the epoxy resin described in JP-A-54-147211. Chemical higher fatty acid amide, JP-A-56-1093
Examples include organic fluoro compounds described in No. 43.

Examples of sizing agents that can be advantageously included in the base paper used in the practice of the present invention include aluminum chloride, sulfuric acid,
Fatty acid metal salts in an embodiment fixed to the pulp with a water-soluble aluminum salt such as polyaluminum chloride and/or an alkyl ketene dimer in an embodiment fixed to the pulp with or without a fatty acid, a water-soluble aluminum salt. Alternatively, a sizing agent that is a combination of an alkyl ketene dimer and an epoxidized higher fatty acid amide can be used. The fatty acid metal salt and/or fatty acid preferably have 12 to 22 carbon atoms, and the amount added is preferably in the range of 0.5 to 4.01 per absolute dry weight of pulp. In addition, the amount of water-soluble aluminum salt added as needed is in the range of 1/20 to 4/l based on the solid weight of the sizing agent.
A range of 1/1 to 1/1 is preferable. Further, as the alkyl ketene dimer, those in which the alkyl group has 8 to 30 carbon atoms, preferably 12 to 18 carbon atoms are preferred. Alkyl ketene dimer is usually commercially available as an emulsion.
There are 0XC, etc. The amount added is 0.2 to 4.0 as alkyl ketene dimer per absolute dry weight of pulp.
The weight range is good.

Examples of polymer compounds that can be advantageously incorporated into the base paper used in the present invention during the preparation of the paper stock slurry include cationic wet strength agents, cationic, anionic or amphoteric strength agents.

As the cationic wet paper strength enhancer, polyamine polyamide shrimp chlorohydrin resin is preferable, and the amount added is in the range of 0.05 to 4.0% by weight, particularly 0.15 to 4.0% by weight, based on the dry weight of the pulp. A range of 1.5% by weight is preferred.

Specific examples include Kaimen 557H and Kaimen 5-25 manufactured by Dick Percules ■. Evinox P-
130 etc.

Examples of cationic, anionic or amphoteric paper strength enhancers include ionized starch described or exemplified in Japanese Patent Publication No. 60-47103, cationic polyvinyl alcohol described or exemplified in Japanese Patent Application No. 62-49699, % cationic polyacrylamide described or exemplified in JP-A-57-185432 and JP-A-57-197539;
Anionic polyacrylamide described or exemplified in Japanese Patent Publication No. 62-23119%,
Examples include amphoteric polyacrylamide percentage described or exemplified in Japanese Patent Publication No. 61-37613 and Japanese Patent Application Laid-open No. 59-31949, and vegetable galactomannan described or exemplified in JP-A-59-125731. The amount of these additives added is preferably in the range of 0.05 to 8 weights, particularly 0.15 to 4 weights, based on the dry weight of the pulp.

! Furthermore, the base paper used in the practice of the present invention may contain various additives during the preparation of the paper stock slurry. As fillers, clay, kaolin, calcium carbonate, barium sulfate, magnesium silicate, titanium oxide, etc.
As an H regulator, caustic soda, soda carbonate, etc., as a coloring pigment, a coloring dye, as a fluorescent whitening agent, JP-A-54-147
No. 033, Patent Application No. 1983-37555, % Application No. 1983-9
The materials described or exemplified in No. 6516 may be contained in appropriate combinations.

Various water-soluble polymers, antistatic agents, and additives can be added to the base paper used in the practice of the present invention by spraying or tab size press. Examples of water-soluble polymers include leprosy-based polymers, polyvinyl alcohol-based polymers, gelatin-based polymers, polyacrylamide-based polymers, cellulose-based polymers, etc. as described or exemplified in Japanese Patent Application No. 63-965:16; Alkali metal salts such as sodium chloride and potassium chloride, alkaline earth metal salts such as calcium chloride and barium chloride, colloidal metal oxides such as colloidal silica, as described or exemplified in No. 63-965i6;
-82242 or exemplified organic antistatic agents, latex, emulsion/L/thin, petroleum resin emulsion, styrene-acrylic acid-acrylic acid ester copolymer, styrene-acrylic acid -Butadiene copolymer.

Latex such as ethylene-vinyl acetate copolymer, styrene-maleic acid-acrylic acid ester copolymer, pigments such as clay, kaolin, Merck, barium sulfate, titanium oxide, etc., and pH regulators such as hydrochloric acid, phosphoric acid, citric acid, etc. It is advantageous to contain acid, caustic soda, soda carbonate, and other additives such as the above-mentioned colored pigments, colored dyes, and optical brighteners in appropriate combinations.

For the production of the base paper used in the practice of the present invention, commonly used paper machines such as Fourdrinier paper machines and circular wire paper machines are used, but I! #Kokai No. 58-37642, JP-A No. 61-260
It is advantageous to employ suitable papermaking methods, such as those described or exemplified in No. 240 and JP-A-61-284762. There are no particular restrictions on the thickness of the base paper, but after making the base paper, JP-A Nos. 58-37642 and 6
Preferably, the base paper is calendered as described or exemplified in No. 0-126397, and its basis weight is preferably 40 f/vl to 250 f/rl.

Polyolefin resins used in the practice of the present invention include homopolymers of olefins such as low-density polyethylene, high-density polyethylene, polypropylene, polybutene, and polybentene, or copolymers of two or more olefins such as ethylene-propylene copolymers. Polymers and mixtures thereof, having various densities and melt viscosity indexes, can be used alone or in combination. In addition, when the resin has a multilayer structure, the outermost layer resin has a melt index (hereinafter abbreviated as MI) of 5 to 20, and the lower layer resin has a melt index (MI) of 5 to 20, for example.
It is also possible to use resins of other properties, such as those of 10.

In the present invention, the resin layer on the image forming side of the photographic support contains 7 to 30% by weight of titanium dioxide pigment, but in the case of a multilayer resin coating, the lower resin layer contains may or may not contain a titanium dioxide pigment. In addition, polyolefin resins contain white pigments such as zinc oxide, Merck and calcium carbonate, fatty acid amides such as stearic acid amide and alaxic acid amide,
Fatty acid metal salts such as zinc stearate, calcium stearate, aluminum stearate, magnesium stearate, zirconium octylate, sodium palmitate, calcium palmitate, sodium laurate, tetrakis[methylene-3(3,5- g tcr
Antioxidants such as t-butyl-4-hydroxyphenyl)propionate comethane, 2,6-tert-butyl-4-methylphenol, cobalt blue, navy blue,
Blue pigments and dyes such as ultramarine, cerulean blue, and phthalocyanine blue, magenta pigments and dyes such as cobalt violet, 7 asto violet, and manganese violet, Tinuvin 320% Tenuvin 326, Tinuvin 328 (
It is preferable to add an appropriate combination of various additives such as ultraviolet absorbers such as those listed above (trade name of Ciba Geigy).

The photographic support produced according to the present invention is produced by a so-called extrusion coating method in which heated and melted polyolefin resin is cast onto a running base paper, and both sides of the support are coated with the resin. At that time, in the case of a multilayer structure, the outermost resin layer on the front side of the photographic support and the inner resin layer are sequentially formed. or continuously, using the so-called Mendem extrusion coating system, or the so-called co-extrusion coating system, in which the outermost resin layer and the inner resin layer are simultaneously extrusion coated in multiple layers. Bx is good. Furthermore, before coating the base paper with the polyolefin resin, it is preferable to subject the base paper to an activation treatment such as a corona discharge treatment or a flame treatment. The surface of the emulsion side of the photographic support is a glossy surface or JP-A-55-2 which does not affect the gloss of the surface of the photographic paper when it is made into photographic paper.
It has a finely rough surface, a matte surface, a silky surface, etc. as described in No. 6507, and the back surface is usually a matte surface, and if necessary, the front surface or both the front and back surfaces are subjected to activation treatment such as corona discharge treatment or flame treatment. can be administered. Further, after the activation process, a subbing process as described in JP-A-61-84643 can be performed. The thickness of the resin layer on the front and back sides of the resin-coated paper is not particularly limited, but is generally 10μ to 50μ.
Advantageously, extrusion coatings are applied to a certain thickness.

The photographic support used in the present invention can be coated with various back coat layers for antistatic purposes, curl prevention, and the like. In addition, in the bank coat layer,
No. 20, Special Publication No. 57-9059, Special Publication No. 57-539
No. 40, Japanese Patent Publication No. 58-56859, Japanese Patent Publication No. 59-21
Inorganic antistatic agents, organic antistatic agents, hydrophilic binders, latexes, curing agents, pigments, surfactants, etc. described or exemplified in No. 4849, JP-A No. 58-184144, etc. can be contained in appropriate combinations. .

The photographic support according to the present invention is coated with various photographic constituent layers and is used for color photographic paper, black and white photographic paper, typesetting photographic paper, copying photographic paper, reversal photographic material, silver salt diffusion. It can be used for various purposes such as transfer method negatives and positives, printing materials, etc. For example, silver chloride, silver bromide, silver chlorobromide, silver iodobromide, and silver chloroiodobromide emulsion layers can be provided. A color coupler is contained in the silver halide photographic emulsion layer,
Multiple silver halide constituent layers can be provided.

Further, a silver salt diffusion transfer image-receiving layer can be provided by containing physical development nuclei. As the binder for these photographic constituent layers, in addition to ordinary gelatin, hydrophilic polymeric substances such as polyvinylpyrrolidone, polyvinyl alcohol, and polysaccharide sulfate ester compounds can be used. Also,
The photographic constituent layer described above may contain various additives.

For example, sensitizing dyes include cyanine dyes and merocyanine dyes; chemical sensitizers include water-soluble gold compounds and sulfur compounds; antifoggants and stabilizers include hydroxy-triazolopyrimidine compounds and mercapto-heterocyclic compounds. Hardeners such as formalin, vinyl sulfone compounds, aziridine compounds, etc. Coating aids, benzene sulfonates, sulfosuccinates, etc., anti-staining agents, dialkylhydroquinone compounds, etc., and other optical brighteners. , a sharpness-enhancing dye, an antistatic agent, a pH adjuster, a fogging agent, and furthermore, water-soluble iridium, water-soluble rhodium compounds, etc. can be contained in appropriate combinations during the production and dispersion of silver halide.

The silver halide photographic material according to the present invention can be exposed to light as described in "Photographic Light-sensitive Materials and Handling Methods" (Kyoritsu Shuppan, written by Gobe Miyamoto, Photographic Technology Course 2), depending on the photographic material.
Multilayer silver halide color photographic materials in which processing such as development, stopping, fixing, bleaching, stabilization, etc. are performed, especially after color development - bath bleach-fixing processing, are CD-III, CD-
It can be processed with any crude drug color developer such as (2) (compounds of 28 m above are trade names of Kodak Co.), droxychrome (trade name of May and Baker Co.), etc.

A developing solution containing such crude drugs may contain a development accelerator such as benzyl alcohol, thallium salt, and aenidone. It is also possible to process with a developer substantially free of benzyl alcohol.

〔Example〕

Next, examples will be described in order to explain the present invention more specifically.

Example 1 A mixed paper of 50 parts by weight of bleached hardwood kraft pulp and 50 parts by weight of softwood sulfide pulp was beaten to a Canadian Standard Freeness of 310d, and to 100 parts by weight, 3 parts by weight of cationized starch and anionized polyacrylamide were added. 0.2 parts by weight, 0.4 parts by weight of alkyl ketene dimer emulsion (as ketene dimer content), and 0.4 parts by weight of polyamideboriadenepichlorohydrin resin, and the basis weight was 16 Qt/W? paper was made.

The obtained wet paper was dried at 110°C, and then 3 parts by weight of carboxy-modified polyvinyl alcohol and 0°C of optical brightener were added.
5 parts by weight, blue dye 0.002 parts by weight, citric acid 0.2
25 f/d of impregnating solution consisting of 97 parts by weight and 97 parts by weight of water.
Impregnated, dried with hot air at 110℃, and further subjected to linear pressure of 90K.
After calendering with v'cm, both surfaces thereof were subjected to corona discharge treatment to produce a base paper for a photographic resin-coated paper.

Next, apply high-density polyethylene (density 0.96
f/l:d, MI=s) and low density polyethylene (density 0
．． 92f/cd, MI=5) at resin temperature 3.
It was coated to a thickness of 30 μm using a melt extrusion coater at 30°C. Next, after thoroughly mixing each of the resin compositions listed in Table 1 on the surface of the base paper, a melt extruder having a screw extruder with an extrusion opening diameter of 65 mm and a T-die with a width of 750 mm was used to extrude the resin compositions at a resin temperature of 320° C. to a thickness of 30 μm. A photographic support containing a titanium oxide pigment and the like was produced by coating to a certain thickness. At that time, the surface resin layer containing titanium oxide pigment etc. was processed into a flat glossy surface, and the back resin layer was processed into a paper-like matte surface. At this time, the upper limit coating speed at which flapping scratches did not occur on the resin surface was recorded for each resin composition. Also, coating speed 12
The number of die lip stains was recorded 2 hours after the start of melt extrusion of each resin composition under 0 m/min conditions.

Note that the numbers in the table represent parts by weight.

Table 1 ■1: Water-containing alumina surface coverage versus master consisting of 50 parts by weight of rutile titanium oxide with 0.5% by weight of titanium oxide (as At20x) and 50 parts by weight of low-density polyethylene with a density of 0.918 tied and MI 8 patch.

02: Water-containing aluminum surface coverage vs. titanium oxide 0.5 weight i
'% (as At20.) rutile type titanium oxide 50 parts by weight 1 group! 1.25 parts by weight, density 0.918η, MI
A master patch consisting of 48.75 parts by weight of low density polyethylene of No. 8.

[Phase] 3: Hydrous alumina surface coverage vs. titanium oxide 0.5
Master patch consisting of 50 parts by weight of rutile-type titanium oxide with weight To (as ALxOs), triethanol surface coverage of 0.5% by weight of titanium oxide, and 50M low-density polyethylene dome with a density of 0.918 tied and MI8.

[Phase] 4: Hydrous alumina surface coverage to titanium oxide 0.5
Weight % as CAL20s), triethanolamine surface coverage vs. titanium oxide 0.5 parts by weight of rutile-type titanium oxide 50 parts by weight, group! 1.25 weight i5: parts, density 0°91
Master patch consisting of 48.75 parts by weight of low density polyethylene of 8f/d, MI8.

@5: Hydrous alumina surface coverage vs. titanium oxide 0.5!
A master patch consisting of 50 parts by weight of rutile titanium oxide of i% (as At20 s) and 50 parts by weight of low-density polyethylene with a density of 0.9181 F/F and MI9.

■6: Rutile type titanium oxide 50 of 0.5% by weight of moated titanium (as LtxOs) to surface coverage of hydrated aluminum
Parts by weight, Ultramarine 1.25 parts by weight, Density 0.918 ties
d. Master patch consisting of 48.75 parts by weight of MI9 low density polyethylene.

[Co.] 7: Hydrous alumina surface coverage vs. titanium oxide 0.5
A master patch consisting of 50 parts by weight of rutile titanium oxide with a triethanolamine surface coverage ratio of 0.5% by weight of titanium oxide, and 50 parts by weight of low-density polyethylene with a density of 0.918 f/% MI9.

[Phase] 8: Hydrous alumina surface coverage vs. titanium oxide 0.5
weight% CAt2Ch), triethanolamine surface coverage vs. titanium oxide 0.5 weight*S rutile type titanium oxide 50 parts by weight, ultramarine blue 1.25 parts by weight, density 0°918f
A, Master patch consisting of 48.75 parts by weight of MI9 low density polyethylene.

@9: The 8hepard Co1or Co
Mpany li! 10 parts by weight of s balt pruna 3,
A master patch consisting of 90 parts by weight of low-density polyethylene with a density of 0.918 f/piece and MI8.

@1o: Master patch consisting of 0.1 part by weight of Chromophthal Blue A3B (manufactured by Ciba Geigy), 0.1 part by weight of low molecular weight polyethylene, and 99.8 parts by weight of low density polyethylene with density Q, 918 tied, MI8.

@11: Structural formula [X! A master patch consisting of 2 parts by weight of fluorescent agent of l/l, 98 parts by weight of low-density polyethylene of MI8, density 0.91Bv.

■12: 0.2 parts by weight of fluorescent agent of structural formula (III), 0.2 parts by weight of low molecular weight polyethylene, density 0.918 f
/at, a master patch consisting of 99.6 parts by weight of MI8 low density polyethylene.

@13: Fluorescent agent of structural formula [■] 0.2 parts by weight, low molecular weight polyethylene 0.2 parts by weight, density 0.918 tied
, a master patch made of 99.6 parts by weight of MI9 low density polyethylene.

@14; Low density polyethylene with a density of 0.918 f/cd and MI8.

@15: Low density polyethylene with density 0.918 tied, MI 9.

A portion of each of the resulting photographic supports was made into black and white photographic paper. The remaining portion was coated with the same amount of gelatin as that contained in the black and white photographic paper.

Whitening effect evaluation method: The color tone of a sample coated with gelatin was evaluated. Evaluation criteria: white → O1, slightly yellow → Δ, yellow → × Sharpness evaluation method 2. Print a density line chart for measuring resolution on black and white photographic paper, and measure the difference in density of the density line print image using a Union Optical microphotometer. The value expressed by the following formula was defined as the resolution.

By myself.

The results are shown in Table 2.

As can be seen from Table 2, the samples containing a fluorescent agent and organic surface-treated titanium oxide (■, ■, ■, ■) have increased lip stains compared to the standard sample (■). On the other hand, samples with physical property values of 4 or less (■, ■, O) have lower upper limit coating speeds. On the other hand, the sample of the present invention, O, has no apter-like scratches even when produced at high speed, has few streaks caused by lip stains, is white, and has high resolution.

Example 2 The results shown in Table 3 were obtained in the same manner as in Example 1, except that the organic surface treatment of titanium oxide in the sample [phase] was changed to the surface treatment shown in Table 3.

It can be seen that if the amount of organic surface treatment is small, there is no effect, and if it is too large, grip stains increase.

Example 3 Sample of Example 1 @ (7) The results shown in Table 4 were obtained in the same manner as in Example 1 except that the total titanium oxide content was changed to the amount listed in Table 4.

Table 4 Table 5 It can be seen that if the titanium oxide content is too low, the resolution will be insufficient, and if it is too high, die lip stains will increase.

Example 4 The results in Table 6 were obtained in the same manner as in Example 1 except that Table 5 was used instead of Table 1.

[Co.] 16: Water-containing Alzuna surface coverage vs. titanium oxide 0.
5% by weight (as AA20 vessel), 50 parts by weight of rutile titanium oxide, 0.5 parts by weight of titanium oxide relative to triethanolamine surface coverage, 2.5 parts by weight of zinc stearate, density 0.918 t/di, Ml low density polyethylene 47
．． Master patch consisting of 5 parts by weight.

@17: 50 parts by weight of rutile-type titanium oxide, ultramarine 1.25 parts by weight, 0.5% by weight of titanium oxide (as 20 g of At) relative to the surface coverage of hydrous alumina, 50 parts by weight of rutile-type titanium oxide, O,Sii% of titanium oxide to the surface coverage of triethanolamine, 2.5 parts by weight of zinc stearate, density 0.918 t/all, MI
A master patch consisting of 46.25 parts by weight of low-density polyethylene No. 9.

@18: 0.2 parts by weight of fluorescent agent with structural formula [■], 0.2 parts by weight of low molecular weight polyethylene, density 0.918 fed,
MI9 low density polyethylene 99. Master patch consisting of Si quantity part.

■19: Fluorescent agent of structural formula [■] 0.2 parts by weight, low molecular weight polyethylene 0.2 parts by weight, density 8.918 t/cd
.

Master pap made of MI9 low density polyethylene.

Note zO: Density 0.960 fed, MI? (F) High density Ml IJ W tyrene.

Note 21: Low density polyethylene with a density of 0.918 fed, MI 9.

Table 6 shows that when the amount of fluorescent agent used is small, the effect of improving white discoloration is small, and when it is too large, the effect of improving white discoloration is saturated, and grip stain also tends to increase.

Example 5 The same procedure as in Example 4 was carried out except that the titanium oxide was coated with hydrated alumina, and the same results were obtained.

〔Effect of the invention〕

By carrying out the present invention, a photographic support with high titanium oxide dispersibility, high sharpness, high whiteness, no streaky thickness abnormalities, and no apter-like scratches can be obtained.

Power, The X axis is L/D.

is a graph plotting measured values. In the figure, 1 is a descending beam, 2 is a load cell, 3 is a plunger, 4 is a spacer, 5 is a cylinder block, 6 is a capillary block, 7 is a constant temperature bath, 8 is a stock cylinder, and 9 is a capillary.

The cylinder diameter d of No. 8 is 10 mm, and the capillary diameter of No. 9 is 1.5 mm. Written amendment (voluntary) August 16, 1999 1. Case description Application dated August 3, 1999 2. Invention Name photo support 3, name of address related to the case of the person making the amendment

Claims (1)

[Claims] 1) In a photographic support made of paper as a substrate and coated with polyolefin on both sides, a) on the side on which an image is provided;
A fluorescent agent (b) has a polyethylene resin layer containing organic surface-treated titanium oxide, and the physical property value n of the resin composition determined by the method described below is 200 ° C. and a shear rate of 1000 /
A photographic support having a sec value of 4.0 or less. Definition of physical property value n: There is a stock cylinder part 8 with a diameter (d) of 10 mm, a capillary part 9 with a diameter (D) of 1.5 mm, and a connecting part connecting them, and the connecting part is conical and the angle θ is 45°. Using a capillary rheometer, these parts are kept at a constant temperature and the stock cylinder 8 is filled with the resin composition. By lowering the descending beam 1 at a constant speed, pressure is applied to the resin composition through the load cell 2, plunger 3, and spacer 4 that is in close contact with the inner wall of the stock cylinder, and the resin composition is extruded from the capillary 9 at a constant shear rate, which causes the A load cell detects the resistance force. This measurement is carried out using capillary length (L) of 10 mm, 20 mm,
The measurements were carried out on three types of 30 mm capillaries, the obtained measurement values were plotted against L/D, and the distance from the intersection of the straight line connecting them with the L/D axis and the L/D axis to the origin was calculated as L/D. Let the value shown in D units be the physical property value n. 2) The photographic support according to claim 1, wherein the treating agent for the organic surface-treated titanium oxide is at least one selected from alkanolamines and low molecular weight polyhydric alcohols. 3) The photographic support according to claim 2, wherein the amount of the alcohol amine surface treated is 0.1 to 5.0% by weight based on the weight of the titanium oxide. 4) The photographic support according to claim 2, wherein the amount of the low molecular weight polyhydric alcohol surface treated is 0.1 to 1.5% by weight based on the weight of the titanium oxide. 5) The content of the organic surface-treated titanium oxide in the resin layer is 9 to 25% by weight based on the weight of the resin composition.
The photographic support according to , 3 or 4. 6) The fluorescent agent is bis-(2-benzoxazolyl)-1,
4-naphthalene type, bis-(2-benzoxazolyl)
-4,4'-Stilbene type fluorescent agent Claims 1, 2,
Photographic support according to 3, 4 or 5. 7) The photographic support according to claim 1, 2, 3, 4, 5 or 6, wherein the amount of the fluorescent agent used is 0.5 to 10 mg/m^2.