JPH07120873A - Substrate for photographic printing paper and its production - Google Patents

Abstract

PURPOSE:To provide a substrate for photographic printing paper into which the infiltration of a developer is reduced at the time of development by incorporating cationic starch, polyamidopolyamine epichlorohydrin and carboxymethyl cellulose. CONSTITUTION:Both sides of a base paper is coated with a film formable resin to constitute the substrate for photographic printing paper. Cationic starch, polyamidopolyamine epichlorohydrin and carboxymethyl cellulose are incorporated into the base paper as a dry paper reinforcing agent. A starch produced from corn, tapioca, potato, etc., and modified with a tertiary or quaternary cation is used as the cationic starch. The amt. of the starch to be added is preferably controlled to 0.05-3.0wt.%, based on the pulp, and that of carboxymethyl cellulose to 0.01-1.0wt.%.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a photographic printing paper support, and more particularly to a photographic printing paper support having both sides of a base paper coated with a resin capable of forming a film.

[0002]

2. Description of the Related Art In recent years, as a support for photographic printing paper, polyethylene is used on both sides of the base paper in order to prevent permeation of the processing liquid in the development and fixing processing of photographs and to shorten the time spent for washing and drying. A water-resistant photographic printing paper support coated with a polyolefin such as the above is preferably used.

On the other hand, with respect to the base paper, an inexpensive sizing agent, an anionic strength enhancer, and an inexpensive aluminum salt are added to the paper stock for the purpose of fixing these anionic chemicals to the pulp in the papermaking process. So-called acid paper, which shows acidity as a result, has been conventionally used. However, in recent years, neutral paper, which is advantageous in terms of improving the preservability of the base paper, closing white water in the paper making process, and preventing corrosion of equipment, has been widely used in general paper in recent years.

By the way, the base paper of the support for photographic paper needs to be strong size paper in order to prevent the permeation of the developing solution from the cut surface of the support during the development processing. Therefore, when a neutral paper is used as a base paper for a photographic paper support, a self-fixing alkyl ketene dimer must be used as a sizing agent and a cationic polyacrylamide must be used as a paper strength agent. . In this case, the neutral range (stock pH = 6.0 or more, 8.5
Papermaking in the following) is in the acidic range (stock pH = 3.5 or more,
(Less than 6.0) causes less water drainage on the wire and increases the drying load, and also causes roll stains such as press rolls because the alkyl ketene dimer is used as a sizing agent. However, it has a drawback that the surface of the base paper thus made becomes slippery.

These drawbacks are ameliorated by using a cationic polyacrylamide having a specific molecular weight and a specific cation value, which is obtained by copolymerization of acrylamide and a cationic monomer.
No. 31843). It has also been found that it is preferable to use anionic polyacrylamide together with the epoxidized higher fatty acid amide in the above system.

Therefore, as a result of further studies on the paper strength agent, the present inventors have found that cationic starch and polyamide polyamine epichlorohydrin, which have not been thought to give particularly good results when used individually, have been studied. When carboxymethyl cellulose and carboxymethyl cellulose are simultaneously used as a paper-strengthening agent, it is possible to easily prevent the generation of process stains in the neutral range, and for photographic paper in which both sides of the obtained base paper are coated with a polyolefin resin. It was found that the permeation of the developing solution from the cut surface of the support can be significantly reduced, and the present invention has been completed.

[0007]

SUMMARY OF THE INVENTION It is, therefore, a first object of the present invention to provide a support for photographic printing paper, in which a developing solution penetrates less during development. A second object of the present invention is that the manufacturing is easy and the manufacturing environment can be improved.
An object is to provide a support for photographic printing paper. A third object of the present invention is to provide a support for photographic printing paper, which has good drainage of the stock on the wire in the papermaking process and does not cause roll stains. A fourth object of the present invention is to provide a method for producing a base paper for a photographic printing paper, in which a developing solution hardly penetrates during development.

[0008]

The above objects of the present invention are to provide a support for photographic printing paper, which comprises a base paper coated with a resin capable of forming a film on both sides, wherein the base paper is a cationic starch or a polyamide polyamine epichlorohydrin. And a carboxymethylcellulose-containing support for photographic paper and a method for producing the same.

The resin capable of forming a film in the present invention includes polyolefin resins such as polyethylene and polypropylene, as well as polybutene, polystyrene, polyvinyl chloride, polyvinylidene chloride, polycarbonate, polyethylene terephthalate, polyamide, polyacrylic acid ester and the like. However, among these, from the viewpoint of melt extrusion suitability when coating the base paper and adhesiveness with the base paper,
It is particularly preferable to use polyethylene.

The molecular weight of these resin capable of forming a film is not particularly limited as long as it is possible to add a white pigment, a coloring pigment or a fluorescent whitening agent to the coating layer formed by extrusion coating. Usually 20,000
Those having a molecular weight in the range of up to 200,000 are used.
There is no particular limitation on the thickness of the resin coating layer, and the conventional
The thickness can be determined according to the thickness of the resin layer for the printing paper support, but generally the thickness is 15 to 50 μm.

Addition of stabilizers such as white pigments, coloring pigments or fluorescent whitening agents, phenols, bisphenols, thiobisphenols, amines, benzophenones, salicylates, benzotriazoles and organometallic compounds to the resin coating layer. You can In particular, it is preferable to add a white pigment and a coloring pigment to the resin coating layer on the side on which the photographic emulsion is coated. As the extrusion coating equipment for extrusion coating the resin, an ordinary polyolefin extruder and a laminator are used.

In the present invention, cationic starch is added as a dry paper strengthening agent. Examples of the cation starch include corn, tapioca, potato, and the like, which are obtained by modifying the starch with a tertiary or quaternary cation. The degree of substitution for cation modification is 0.02 to 0.
No. 06 is preferable, and the addition amount thereof is 0.
It is preferably 5 to 5.0% by weight, and particularly preferably 1 to 3% by weight.

Further, in the present invention, it is preferable to add polyacrylamide as a dry paper strengthening agent other than the cationic starch. Examples of this polyacrylamide include anionic polyacrylamide, cationic polyacrylamide, and amphoteric polyacrylamide. Among these, in particular, amphoteric polyacrylamide is an amphoteric copolymer obtained by copolymerizing an anion monomer and a cation monomer while using acrylamide or methacrylamide as a main monomer component.
The average molecular weight measured by the PC method (gel permeation chromatography) is preferably 2,000,000 to 5,000,000, and particularly preferably 2,000,000 to 3.5,000,000. The amount of the amphoteric polyacrylamide used is preferably in the range of 0.01 to 5.0% by weight, and particularly preferably in the range of 0.1 to 1.0% by weight, based on the pulp.

In the present invention, polyamide polyamine epichlorohydrin is further added as a wet strength agent. The addition amount of this polyamide polyamine epichlorohydrin is preferably in the range of 0.05 to 3.0% by weight, and particularly preferably in the range of 0.2 to 1.0% by weight, based on the pulp. .

The carboxymethyl cellulose used in the present invention is one in which a carboxymethyl group is ether-bonded to the hydroxyl group of cellulose, and in the present invention,
Particularly, its sodium salt is preferably used. The degree of etherification of this carboxymethyl cellulose is 0.5 to
It is preferably 0.8 and the average degree of polymerization is 300.
It is preferably about 500. The amount of carboxymethyl cellulose added is preferably in the range of 0.01 to 1.0 wt% with respect to the pulp, and particularly 0.05 to 0.
It is preferably in the range of 5% by weight.

In the present invention, it is preferable to further use an epoxidized higher fatty acid amide and / or an alkyl ketene dimer. The epoxidized higher fatty acid amide used in the present invention acts as a sizing agent, and specific examples thereof include Japanese Patent Publication Nos. 38-20601 and 39-4507 and U.S. Pat. No. 3,692,092. Those obtained by condensation of fatty acids and polyvalent amines as described, those obtained by reaction of alkenyl succinic acid and polyvalent amines as described in JP-A-51-1705, and the like are mentioned. You can

In the present invention, among the above fatty acids, higher aliphatic monocarboxylic acids and polyvalent carboxylic acids having 8 to 30 carbon atoms are preferable, and those having 12 to 25 carbon atoms are particularly preferable. Specific examples of such an aliphatic carboxylic acid include, for example, stearic acid, oleic acid, lauric acid, palmitic acid, arachidic acid, behenic acid, tall oil fatty acid,
Examples thereof include alkyl succinic acid and alkenyl succinic acid, and among these, behenic acid is particularly preferable.
Two or more kinds of fatty acids may be used in combination.

As the polyvalent amine, polyalkylene polyamines are preferable, and those having 2 to 3 methylene groups between amino groups are preferable. Specific examples include diethylenetriamine, triethylenetetramine,
Examples include tetraethylenepentamine, pentaethylenehexamine, dipropylenetriamine, tripropylenetetramine, aminoethylethanolamine and the like.

In the present invention, it is preferable to use a reaction product of an aliphatic carboxylic acid and a polyvalent amine as a quaternary salt with epichlorohydrin so that the sizing agent does not fall off from the pulp by mechanical stirring. . The amount of the epoxidized higher aliphatic amide used in the present invention is preferably 0.1 to 3.0% by weight, and particularly preferably 0.3 to 1.5% by weight, based on the pulp.

The alkyl ketene dimer used in the present invention is preferably one having a higher fatty acid having 8 to 30 carbon atoms, and particularly preferably an alkyl ketene dimer having behenic acid. The addition amount is preferably 0.1 to 3.0% by weight, and particularly preferably 0.3 to 1.5%, relative to the pulp.

In the present invention, it is preferable to add a polyvalent metal salt as a fixing agent to the pulp slurry. As such a polyvalent metal salt, water-soluble aluminum salts such as aluminum sulfate and aluminum chloride are particularly preferable. These fixing agents are preferably added to the paper material in an amount of 0.1 to 1.0% by weight. When the pH of the pulp slurry becomes acidic due to the addition of these polyvalent metal salts, for example, an alkaline substance such as sodium hydroxide or sodium aluminate is added to adjust the pH to 6.0 to 7.5. It is preferable to control to the range of nature in order to improve the storability of the base paper and thus the storability of the photographic paper support.

In the present invention, the zeta potential of the pulp slurry thus obtained is preferably in the range of -10 to +5 mV, and particularly preferably in the range of -5 to +1 mV. If the zeta potential is less than -10 mV or exceeds +5 mV, the depth of penetration of the developing solution from the cut end face of the photographic paper at the time of development becomes large, and a photographic photographic paper that can be used cannot be obtained.

The zeta potential of the pulp slurry can be adjusted by adding an anionic substance to the pulp slurry. This is because pulp is generally an anion, but paper strength agents, sizing agents, etc., which are added to obtain the properties necessary for the neutral base paper for photographic paper, are preferably kaoth and also have a large addition amount. This is because the pulp slurry after adding the chemicals is usually khaotin. As the zeta-potential regulator, carboxymethyl cellulose is preferable, and its sodium salt is particularly preferable, but carboxy-modified polyvinyl alcohol, sodium polyacrylate, etc. can be used in combination.

In the present invention, clay, if necessary,
Filler such as talc, kaolin, calcium carbonate, titanium oxide or urea resin fine particles; sizing agent such as rosin, higher fatty acid salt, paraffin wax, alkenyl succinic anhydride, styrene acrylic acid copolymer; paper strength agent such as gelatin Wet paper strength agents such as melamine formalin condensates; other dyes, optical brighteners, defoaming agents and the like may be added.

The alkaline substance is added while adjusting the final pH of the stock to be 6.0 to 8.5. The epoxidized higher fatty acid amide and the alkyl ketene dimer show good sizing properties in any addition order, but it is preferable to add them in the first half of the above addition order because the dispersion is better and the sizing property is good.

A liquid containing various water-soluble additives may be impregnated and applied to the above-mentioned base paper substrate with a size press, a tab size or a gate roll coater. Examples of such water-soluble additives include starch, polyvinyl alcohol,
There are polymer compounds such as carboxy-modified polyvinyl alcohol, carboxymethyl cellulose, hydroxyethyl cellulose, sodium alginate, cellulose sulfate, gelatin and casein, and metal salts such as calcium chloride, sodium chloride and sodium sulfate.

In the liquid containing the above water-soluble additive, hygroscopic substances such as glycerin and polyethylene glycol; coloring and whitening substances such as dyes and fluorescent whitening agents; caustic soda, ammonium water, hydrochloric acid, sulfuric acid, A pH control agent such as sodium carbonate may be added. In addition, a pigment or the like can be added to the aqueous solution, if necessary.

The type and thickness of the base paper substrate are not particularly limited, but the basis weight is 50 g / m ² to 250.
g / m ² is desirable, and from the viewpoint of the flatness of the photographic printing paper, a base paper excellent in surface smoothness and flatness is desirable,
Surface treatment is preferably performed by applying heat and pressure with a machine calender, a super calender, or the like. The support for photographic printing paper of the present invention is coated with a photographic emulsion layer on its glossy surface and dried to give a photographic printing paper.
Various modes are possible, such as the provision of the print storage layer disclosed in No. 6256.

[0029]

The photographic paper support of the present invention comprises a cation starch, a polyamide polyamine epichlorohydrin and carboxymethyl cellulose, and optionally an epoxidized higher fatty acid amide and / or an alkyl ketene dimer in a neutral region. Using the base paper made in, the both sides are coated with a resin capable of forming a film, so that not only the permeation of the developer from the end of the cut surface can be significantly reduced, but also stains in the paper making process It can be reduced.

[0030]

The present invention will be described in more detail with reference to the following examples, but the present invention is not limited thereto.

Example 1 Wood pulp having a LBKP / LBSP weight ratio of 70/30 was beaten to obtain a pulp slurry having a Canadian freeness of 250 ml. While stirring the obtained pulp slurry, with respect to 100 parts by weight of pulp,
2 parts by weight of cation starch, 0.2 part by weight of epoxidized behenic acid amide, 0.7 part by weight of polyamide polyamine epichlorohydrin, 0.4 part by weight of alkyl ketene dimer composed of behenic acid, and 0.2 part by weight of carboxymethyl cellulose. After each addition, the pH is 7.
Sodium hydroxide was added so that it became 5.

The zeta potential of the obtained pulp slurry was measured by a zeta potential measuring device MO manufactured by Penken.
It was +1 mV as measured by DEL501. Then 180 g / m ² from this pulp slurry
A size liquid having the composition shown in Table 1 below is size-pressed onto the surface of the base paper obtained by paper-making so that the adhesion amount of the liquid is 30 g /
It was attached so as to be m ² .

[0033]

[Table 1] ─────────────────────────────────── Polyvinyl alcohol: 5.0 wt% Calcium chloride: 4.0 wt% Optical brightener: 0.5 wt% Antifoaming agent: 0.005 wt% Water: 90.495 wt% ──────────────────── ────────────────

The thickness of the obtained size liquid-adhered paper was adjusted to 173 μm using a machine calendar, the back surface was subjected to corona discharge treatment, and then polyethylene having a density of 0.980 g / m ² was coated to about 30 μm. After further corona discharge treatment on the front surface (photographic emulsion coated side),
Density containing 10 wt% titanium oxide 0.960 g /
m ² of polyethylene was coated to a thickness of about 30 μm to obtain a support for photographic printing paper. The color photographic paper obtained by applying a color emulsion to the obtained photographic paper support was developed using an automatic processor, and the depth of penetration of the processing liquid from the edges was measured for the processed photographic paper. As a result of measurement, the penetration depth was as small as 0.43 mm and it was a very good photographic printing paper.

Example 2. Except that the additive of carboxymethyl cellulose used in Example 1 was 0.35 parts by weight,
A paper stock was obtained in exactly the same manner as in Example 1. The penetration depth of the obtained printing paper measured in exactly the same manner as in Example 1 was 0.39 mm, which was a very small photographic printing paper. Moreover, when the zeta potential was measured, it was -5 mV.
Met.

Comparative Example 1. A paper stock was obtained in exactly the same manner as in Example 1 except that carboxymethyl cellulose was not added. The penetration depth of the obtained printing paper measured in exactly the same manner as in Example 1 was 0.67 mm, which was too large to be used. The zeta potential was measured and found to be +23 mV.

Example 3 A pulp slurry was obtained in the same manner as in Example 1, and while stirring the slurry, 2 parts by weight of cationic starch, 0.2 part by weight of epoxidized behenic acid amide, and polyamide were used with respect to 100 parts by weight of pulp. Polyamine epichlorohydrin 0.
4 parts by weight, 0.7 parts by weight of alkyl ketene dimer composed of behenic acid, and 0.2 parts by weight of carboxymethyl cellulose were added, and then sodium hydroxide was added so that the pH became 7. When the penetration depth of the obtained paper material was measured, the penetration depth was as small as 0.38 mm,
It was a very good photographic printing paper. The zeta potential was -3 mV.

Comparative Example 2. A paper stock was obtained in exactly the same manner as in Example 3 except that carboxymethyl cellulose was not added. The penetration depth of the obtained printing paper measured in exactly the same manner as in Example 1 was as large as 0.61 mm, and it was not usable. The zeta potential was measured and found to be +12 mV.

Comparative Example 3. A paper stock was obtained in exactly the same manner as in Example 1 except that the cationic starch was not added. The penetration depth of the obtained photographic paper, measured in exactly the same manner as in Example 1, was as large as 1.21 mm, and it was not usable. Also, when the zeta potential was measured,
It was −12 mV.

Comparative Example 4. A paper stock was obtained in exactly the same manner as in Example 1 except that the polyamide polyamine epichlorohydrin was not added. The penetration depth of the obtained printing paper measured in exactly the same manner as in Example 1 was as large as 1.02 mm, and it was not usable. The zeta potential was measured and found to be -30 mV.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Office reference number FI Technical display location D21H 17/25 17/28 17/46 27/00 7199-3B D21H 3/28 7199-3B 3 / 48 7199-3B 5/00 Z

Claims (3)

[Claims] 1. A photographic printing paper support comprising both sides of a base paper coated with a resin capable of forming a film, wherein the base paper contains cation starch, polyamide polyamine epichlorohydrin and carboxymethyl cellulose. Support for paper. 2. The base paper further contains an epoxidized higher fatty acid amide and / or an alkyl ketene dimer, and is produced in a neutral range where the pH of the stock is 6.5 to 8.5. The support for photographic printing paper according to 1. 3. A method for producing a support for photographic paper, which comprises coating a resin having film-forming ability on both sides of a base paper made from a pulp slurry containing at least cationic starch, polyamide polyamine epichlorohydrin and carboxymethyl cellulose, When making the base paper, the zeta potential of the pulp slurry is -10 to +5 m.
A method for producing a support for photographic printing paper, which comprises adjusting the range to V.