JPH0782696A - Production of support for photograph - Google Patents

Abstract

PURPOSE:To obtain a support for photograph printing paper hardly occurring slime and having good photographing properties in raw paper making process of a support for photograph. CONSTITUTION:In a raw paper making process, 5-500ppm (W/W) of 1,5- pentanedial is added to head box slurry to reduce occurrence of slime and stain of foil. Further, a support for photography, capable of providing photograph printing paper free from any dot or fogging and having excellent photographing properties is obtained thereby.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a photographic support, and more particularly to a method for producing slime in the step of producing a base paper for a photographic support.

[0002]

2. Description of the Related Art A photographic printing paper is a photographic printing paper coated with a silver halide emulsion layer using baryta paper as a support.
Recently, a photographic paper has been used in which a silver halide emulsion layer is coated on a water-resistant support in which both sides of the paper are coated with a polyolefin resin.

When manufacturing these photographic supports,
First of all, there is a step of papermaking the base paper.
In this step, pulp fibers are dispersed in water together with various chemicals, and the suspension (pulp slurry) is made into paper by a Fourdrinier or cylinder paper machine and dried to form a web. During such a papermaking process, since the temperature is moderate and the nutrients are abundant, the microorganisms easily propagate, and the microorganisms and metabolites thereof are aggregated to form so-called slime, which is a viscous mud. If such slime becomes a certain size and is peeled from the attached wire part, chest, wall of the pipe, etc. and mixed into the pulp slurry, stains and holes may be generated in the papermaking base paper, and Causes problems such as paper scraps, stains on the device, and a bad odor, and seriously affects quality and operation.

Generally, a photographic support is required to have a stricter required quality than general paper and to have almost no defects in the base paper. For that purpose, it is necessary to prevent slime generation in the papermaking process as much as possible. Is. As a method for preventing slime in the papermaking process, it is known to add a bactericidal agent called a slime control agent to the pulp slurry to kill bacteria that cause slime or prevent its growth.

As the slime control agent, there are organic mercury agents, organic nitrogen agents, organic bromine agents, and the like. When these slime control agents are applied as they are, they have the effect of preventing slime, but the photograph However, there is a bad influence on the property, and spots and fogs are generated on the photographic paper after development, and the quality as a product is remarkably impaired, or the requirements cannot be sufficiently satisfied. Therefore, as a slime control agent suitable for photography, JP-A-59-1
In Japanese Patent No. 28537, a morpholine slime control agent is proposed. Also, JP-A-59-1319
In JP-A-29-29, 5-chloro-2-methyl-4-isothiazoline or the like is proposed as a thiazoline-based slime control agent, but it was not sufficient in terms of the effect on photographic properties and the effect of preventing slime.

[0006]

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for producing a photographic support which is capable of sufficiently preventing the generation of slime in the base paper making process of the photographic support, and having few spots and perforations. To do. Furthermore, it is to provide a method for producing a photographic support that does not adversely affect the photographic emulsion.

[0007]

Means for Solving the Problems As a result of intensive studies to solve the above-mentioned problems, the present inventors have found that 1,5-pentanedial is added to the papermaking process of the base paper of the photographic support. As a result, they have found that the object is achieved, and have completed the present invention.

1,5-Pentanedial is registered as an existing chemical substance, belongs to an organic chain low molecular weight compound, and has a code number of 2-509.

[0009]

[Chemical 1]

As a standard for measuring the generation of slime in the papermaking process of the base paper, there is a method of measuring the viable cell count in the pulp slurry. The viable cell count by this measurement method is generally 10
It is preferably ⁴ cells / ml or less, more preferably 10 ³ cells / ml or less. The viable cell count is 10 ⁷ / m
When it is more than 1, the slime becomes a certain size and peels off from the adhered wire part, chest, wall of the pipe, etc., and is mixed into pulp slurry, and stains and bad odors are generated in the papermaking process. It will be easier.

Generally, the pulp slurry concentration used during papermaking is 0.5 to 2.0 (W / W)%. In particular, it is preferably 0.9 to 1.2%. When the pulp slurry concentration is less than 0.5%, the dehydration rate on the paper machine is remarkably lowered, and the paper is dried with a high water content, so that the drying shrinkage becomes large and the surface wrinkles deteriorate and the mechanical strength decreases. . On the other hand, when a pulp slurry having a concentration of more than 2.0% is used, flocs are formed more frequently and aggregation frequently occurs, resulting in poor formation and poor surface texture.

The proper amount of the slime control agent of the present invention is 5 with respect to the headbox pulp slurry.
~ 500 ppm (W / W) is to be added. 5pp
If it is less than m, there is almost no slime control effect,
Slime is generated, which leads to defects such as paper scraps, stains on the base paper, and perforations, making it impossible to achieve the purpose. Also, 500p
When it is more than pm, the effect as a slime control agent is not improved to a certain level or higher and tends to be saturated, which is not preferable because the cost is increased and the photographic emulsion is adversely affected.

As the place of addition of 1,5-pentanedial, pulp, chemicals or the like may be added at the time of first batch charging, or may be continuously added to the pulp slurry immediately before papermaking. . As a method of addition, it is preferable to use a preparation dissolved in an appropriate amount with alcohol, water or the like, and the preparation may be diluted with water and added.

The pulp used in the present invention may be ordinary wood pulp, synthetic pulp, synthetic fiber or the like. Among these, the softwood pulp, the hardwood pulp, and the hardwood mixed pulp wood pulp are effective.

These pulps can contain various additives. For example, as a dry paper strengthening agent, cationized starch, cationized polyacrylamide,
Anionized polyacrylamide, carboxyl modified polyvinyl alcohol, gelatin and the like can be contained. As the sizing agent, fatty acid salt, rosin derivative, alkyl ketene dimer, petroleum resin emulsion,
Higher fatty acid amides and the like can be included. Further, as a pigment, kaolin, barium sulfate, titanium oxide, etc., as a wet paper strength enhancer, a urea resin, an epoxidized polyamide resin, etc., and as a fixing agent, a polyvalent metal salt such as aluminum chloride, a cationized starch, etc. A cation-modified polymer, a caustic soda, a sodium carbonate or the like as a pH adjusting agent, a salt, a sodium sulfate or the like as an inorganic electrolyte, other dyes, an optical brightening agent and the like can be appropriately combined and added.

In order to use a base paper made from this pulp slurry as a photographic support, a so-called baryta paper coated with a liquid in which barium sulfate is dispersed in gelatin may be used. Both sides of the base paper are coated with a polyolefin resin. It may be used as resin coated paper which is extrusion coated.

The photographic support of the present invention can be provided with various silver halide photographic emulsion layers. The silver halide emulsion layer can contain additives such as a sensitizing dye, a chemical sensitizer, an antifoggant, an optical brightener, a hardener and an antistatic agent. A backing layer may be provided on the back surface of the photographic support of the present invention according to the purpose, or an undercoat layer may be provided according to the purpose.

[0018]

When paper is made by adding 1,5-pentanedial as in the present invention, slime is less likely to occur, and photographic printing paper coated with a polyolefin resin on the paper thus produced is used as a paper after development. No fogging occurs.

[0019]

The present invention will be described in detail with reference to Examples. The present invention is not limited to the examples. In the following, "part" means "part by weight" and "%" means (W / W) standard%. 50 parts of hardwood bleached kraft pulp (LBKP) 50 parts of hardwood sulfite pulp (LBSP) was beaten up to 320 ml with Canadian standard freeness, and the pulp slurry was added to the pulp in weight% to -size-alkyl. Ketene dimer (AS-24 manufactured by Japan PMC) 0.5% -Strengthening agent-Polyacrylamide (Stargum-A-15 manufactured by Starlight Chemical Co., Ltd.) 0.5% Cationized starch (Neo-Tac 130 manufactured by Nissho Kako) 2.0% Polyamide 0.5% of epichlorohydrin (WS525 manufactured by Japan PMC) was added to prepare a 1% pulp slurry.

Examples 1 to 4 A 50% preparation of 1,5-pentanedial was continuously added to this pulp slurry as a slime control agent. The amount of 1,5-pentanedial solid content added was as follows, and they were Examples 1 to 4, respectively. Example 1 1,5-pentanedial 5 ppm Example 2 〃 50 ppm Example 3 〃 100 ppm Example 4 〃 500 ppm

These slurries were weighed with a Fourdrinier paper machine at a basis weight of 17
Papermaking was carried out so as to obtain 0 g / m ² . Continuous 4 of these base papers
After daily papermaking, the viable cell count of white water was measured. The viable cell count was measured according to JIS-K0101 industrial water test method.
In addition, stains in the papermaking process such as foils and wire rolls in the wire portion of the paper machine were also observed.

A polyethylene composition in which anatase-type titanium oxide was uniformly dispersed was mixed with 100 parts by weight of low-density polyethylene having a density of 0.918 g / cm ^{3 in} the produced base paper so that the titanium pigment concentration was 10 parts, It was melted at 320 ° C., and extrusion-coated to a thickness of 30 μm. Also in the other surface, 50 parts of high density polyethylene resin of density 0.962 g / cm ^3, a mixed resin of a low density Poechiren 50 parts of a density 0.918 g / cm ^3, was melted at similarly 320 ° C. The thickness 27
Extrusion coating was performed so as to have a thickness of μm to obtain a photographic support. The surface of the layer containing titanium oxide of this support was subjected to corona treatment, and then coated with an emulsion for color photographic paper to prepare a color photographic paper. After exposing this photographic paper by the normal exposure method,
Color development processing was performed, and the degree of occurrence of spots was observed.
Further, this photographic printing paper was subjected to color development processing without being exposed to light, and the fog density was observed and compared. The results are shown in Table 1.

[Comparative Examples 1 to 4] A pulp slurry was prepared in the same manner as in Examples, Comparative Example 1 without a slime control agent, and in Comparative Examples 2 to 5, samples were prepared in the same manner as in Comparative Examples. 25-Chloro-2-methyl-4-isothiazolin-3-one 1 ppm Comparative Example 3 〃 50 ppm was continuously added. Further, Comparative Example 4 1,5-pentanedial 1 ppm and Comparative Example 5 550 ppm were continuously added. The pulp slurry after addition of the slime control agent was made into a paper by a Fourdrinier paper machine as in the example, subjected to resin coating processing, and further coated with an emulsion for color printing paper to prepare a color printing paper. Evaluation of spots and fog on color photographic paper was carried out in the same manner as in the examples. The viable cell count of the pulp slurry in papermaking was also measured in the same manner as in the example. The results are shown in Table 1.

[0024]

[Table 1]

As can be seen from Table 1, when 1,5-pentanedial is used as in Examples 1 and 2, the number of bacteria generated in the papermaking process is small and the stain in the papermaking process is small. Further, it is understood that the photographic property is also good. However,
When the slime control agent was not added as in Comparative Example 1, slime was generated, the stain in the papermaking process was severe, and the base paper thus produced had spot holes and the like. Stopped. As in Comparative Examples 2 and 3,
When 5-chloro-2-methyl-4-isothiazolin-3-one is used, when the amount added is small, the papermaking process is contaminated, and there is a problem in continuous papermaking. Was recognized. Conversely, if the addition amount is large,
Although there is little stain in the paper making process, the photographic property is very poor and a large number of spots are generated, which is a serious problem in terms of quality as a photographic printing paper, and it does not endure practical use and cannot be a product. Further, even if 1,5-pentanedial is used as in Comparative Examples 4 and 5, there is no problem in photographic properties when the amount added is small, but stains in the papermaking process pose a problem, and long-term It cannot withstand continuous papermaking. Further, when the amount of addition is large, there is no problem in terms of stains and photographic properties, but some fog is generated and it cannot be put to practical use as a photographic printing paper.

[0026]

INDUSTRIAL APPLICABILITY According to the production method of the present invention, in producing a photographic support base paper, generation of slime is suppressed and the quality and productivity of the base paper are good, and the photographic emulsion is used as a photographic support. Even when the layers were formed, a photographic printing paper was obtained which had no adverse effect as printing paper.

Claims (1)

[Claims] 1. A photographic support characterized in that, in the step of making a base paper for a photographic support, 5 to 500 ppm (W / W) of 1,5-pentanedial is added to a headbox pulp slurry. Body manufacturing method.