JPH07120874A - Substrate for photographic printing paper - 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 by incorporating a copolymer of the acrylamide compd. and diallylamine salt into the base paper. CONSTITUTION:Both sides of a base paper are coated with a film formable resin to constitute the substrate for photographic printing paper. A copolymer of the acrylamide compd. and diallylamine salt is incorporated into the base paper, and an acrylamide or a methacrylamide is used as the acrylamide compd. of the copolymer. The hydrochloride, sulfate, phosphate, formate, acetate and propionate of the diallyamine are used as the diallylamine salt. The amt. of the copolymer to be added is controlled to 0.01-2.0wt.%, based on the pulp. Further, the epoxide of a higher fatty acid amide or a alkylketene dimer can be added to the paper for producing the base paper in addition to the copolymer to obtain a strong sized paper.

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 for a support for photographic paper needs to be a 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 printing paper, a self-fixing alkyl ketene dimer is used as a sizing agent, and a cationic polyacrylamide must be used as a paper strength agent.
In this case, since the alkyl ketene dimer is used as a sizing agent, roll stains such as a press roll occur,
It has a drawback that the surface of the raw 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.

As a result of further studies on the paper strength agent, the present inventors have found that a copolymer of an acrylamide compound and a diallylamine salt, which has not been thought to give good results, is extremely useful. , By using this as a paper-strengthening agent, the penetration of the developer from the cut surface of the support for printing paper in which both sides of the obtained base paper are coated with polyolefin resin is significantly reduced. The inventors have found that it is also possible to reduce the above, and have completed the present invention.

[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 to provide a support for photographic printing paper which is easy to manufacture and can improve the manufacturing environment. Third of the present invention
It is an object of the present invention to provide a support for photographic printing paper which can reduce the amount of sizing agent added and can reduce stains in the paper making and laminating steps.

[0008]

The above objects of the present invention are to provide a support for a photographic printing paper, which comprises a base paper coated on both sides with a resin capable of forming a film, wherein the base paper contains an acrylamide compound and a diallylamine salt. It was achieved by a photographic paper support characterized by containing a copolymer of

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 the 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 in the extrusion coated coating layer, but it is usually 20. , 000-200,
Those having a molecular weight in the range of 000 are used. The thickness of the resin coating layer is not particularly limited and can be determined according to the thickness of the conventional resin layer for a photographic paper support, but the thickness is generally 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.

As the acrylamide compound in the copolymer of the acrylamide compound and the diallylamine salt used in the present invention, acrylamide or methylmethacrylamide is used, and as the diallylamine salt,
An inorganic acid salt of diallylamine such as hydrochloric acid, sulfuric acid or phosphoric acid or an organic acid salt such as formic acid, acetic acid or propionic acid is used. The molar ratio of this acrylamide compound and diallylamine salt is preferably in the range of 1/1 to 10/1.

In addition to the above two components, if necessary, a third component
Other vinyl monomers such as acrylonitrile, vinyl acetate, acrylic acid, dimethylaminoethyl acrylate and the like can be copolymerized as a component. These copolymers have an average molecular weight of 50,000 to 100 as measured by the GPC method (gel permeation chromatography).
10,000 is preferable, and 100,000 to 500,000 is particularly preferable. The addition amount of these copolymers is preferably in the range of 0.01 to 2.0% by weight, and particularly preferably in the range of 0.05 to 0.5% by weight, based on the pulp.

In the present invention, from the viewpoint of a strong size paper that can be used as a photographic printing paper, in addition to the copolymer of the above acrylamide compound and diallylamine salt, it is further epoxidized in the stock for producing base paper. It is preferred to add higher fatty acid amides and / or alkyl ketene dimers.

The epoxidized higher fatty acid amide used in the present invention functions as a sizing agent, and specific examples thereof include, for example, Japanese Examined Patent Publication Nos. 38-20601 and 39-39.
No. 4507 and US Pat. No. 3,692,092, which are obtained by condensation of a fatty acid and a polyvalent amine, and alkenyl succinic acid as described in JP-A-51-1705. The thing obtained by reaction with a polyvalent amine can be mentioned.

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 based on the pulp,
It is particularly preferably 0.3 to 1.5% by weight.

In the present invention, in the pulp slurry,
It is preferable to add a polyvalent metal salt as a fixing agent. Examples of such polyvalent metal salts include aluminum sulfate,
Water soluble aluminum salts such as aluminum chloride are preferred. These fixing agents are contained in the paper stock in an amount of 0.1 to 1.0% by weight.
It is preferable to add. 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 8.5. 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.

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 amount added is preferably 0.1 to 3.0% by weight, and particularly preferably 0.3 to 1.5% by weight, based on the pulp.

In the present invention, it is preferable to add cation starch and polyacrylamide as a dry paper strengthening agent. Examples of the cation starch include starch made from corn, tapioca, potato or the like as a raw material, which is modified with a tertiary or quaternary cation. The degree of substitution for cation modification is preferably 0.02 to 0.06, and the addition amount thereof is preferably 0.5 to 5.0% by weight, particularly 1 to 3% by weight, based on the pulp. It is preferable.

Examples of 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, and is a GPC method (gel permeation chromatography). ), The average molecular weight is 2 to 5,000,000. The average molecular weight is preferably 2,000,000 to 3.5,000,000.

The amount of the amphoteric polyacrylamide having an average molecular weight of 2 to 5 million is 0.
It is preferably in the range of 01 to 5.0% by weight, particularly preferably in the range of 0.1 to 1.0% by weight. Further, in the present invention, it is preferable to add polyamide polyamine epichlorohydrin as a wet paper strengthening agent in an amount of 0.05 to 3% by weight, particularly 0.2 to 1.0% by weight, based on the pulp.

In the present invention, clay, if necessary,
Fillers such as talc, kaolin, calcium carbonate, titanium oxide or urea resin fine particles; sizing agents such as rosin, higher fatty acid salts, paraffin wax, alkenyl succinic anhydride, styrene acrylic acid copolymers; carboxymethyl cellulose, gelatin, casein , Carboxy-modified polyvinyl alcohol, other dyes, optical brighteners, antifoaming agents, etc. may be added.

As a method of adding each chemical to the paper stock, it is preferable to add anionic polyacrylamide, a water-soluble aluminum salt, an alkaline substance, and a copolymer of an acrylamide compound and a diallylamine salt in this order. The alkaline substance is added while adjusting the final pH of the stock to be 6.5 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. The order of addition of a wet paper strength agent such as polyamide polyamine epichlorohydrin, which is added as necessary, is arbitrary.

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. Type and thickness of the base paper substrate is not particularly limited, the basis weight is desirably ^{50g / m 2 ~250g / m 2} , also from the viewpoint of flatness of photographic paper, the surface of the A base paper excellent in smoothness and flatness is desirable, and it is preferable to apply heat and pressure with a machine calender, a super calender or the like for surface treatment. 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. On the other side, for example, a print preservation layer disclosed in JP-A-62-6256. Can be provided in various ways.

[0028]

The photographic paper support of the present invention comprises a copolymer of an acrylamide compound and a diallylamine salt and, if necessary, an epoxidized higher fatty acid amide and / or an alkyl ketene dimer in combination for neutralization. Since the base paper made in the area is coated on both sides with a resin capable of forming a film, it is possible not only to significantly reduce the permeation of the developing solution from the end of the cut surface, but also to use a sizing agent, especially alkyl. Since the addition of ketene dimer can be reduced, it is possible to reduce stains in the paper making and laminating steps.

[0029]

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 The weight ratio of LBKP / LBSP / NBSP was 70/15 /
A wood pulp of 15 was beaten to obtain a pulp slurry having a Canadian freeness of 280 ml. While stirring the obtained pulp slurry, 2 parts by weight of cation starch, 0.3 parts by weight of epoxidized behenic acid amide, 0.4 parts by weight of polyamide polyamine epichlorohydrin, and 100 parts by weight of pulp are alkyl ketene composed of behenic acid. 0.5 part by weight of dimer and 0.05 part by weight of a copolymer (molecular weight 250,000) of acrylamide / diallylamine sulfate (molar ratio: 70/30) were added. Further, NaHCO ₃ was added to adjust the pH of the stock to 8.0.

A solution having the composition shown in the following Table 1 was size-pressed onto the surface of the base paper which was made from this pulp slurry so as to have a weight of 180 g / m ^2, and was adhered so that the amount of the liquid deposited would be 30 g / m ² . .

[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 calender, 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. Furthermore, after the front surface (the side coated with the photographic emulsion) was subjected to corona discharge treatment, a density of 0.960 containing 10% by weight of titanium oxide was obtained.
A support for photographic printing paper was obtained by coating about 30 μm of polyethylene of g / m ² .

The color photographic paper obtained by applying a color emulsion to the obtained photographic paper support was developed using an automatic processor, and the processed photographic paper was permeated with the processing solution from the edges. When the depth was measured, as shown in Table 2, the penetration depth was as small as 0.43 mm and it was a very good photographic printing paper.

[Table 2]

Comparative Example 1. A paper stock was obtained in exactly the same manner as in Example 1 except that the copolymer of acrylamide / diallylamine sulfate used in Example 1 was not added. The penetration depth of the obtained printing paper measured in exactly the same manner as in Example 1 was 0.73 mm, which was too large to be used.

Examples 2-3 and Comparative Examples 2-3. A paper stock was obtained in the same manner as in Example 1 except that the chemical addition amounts shown in Table 2 were used, and the penetration depth of each stock was measured. as a result,
Examples 2 and 3 have penetration depths of 0.41 and 0.3, respectively.
Although it was as small as 8 mm, it was a very good photographic printing paper,
In Comparative Examples 2 and 3, the penetration depth was 0.61, respectively.
It was as large as 0.65 mm and could not be used.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification number Office reference number FI technical display location D21H 17/03 17/37 27/00 7199-3B D21H 5/00 Z

Claims (2)

[Claims] 1. A photographic printing paper support obtained by coating both sides of a raw paper with a resin capable of forming a film, wherein the raw paper contains a copolymer of an acrylamide compound and a diallylamine salt. Support for photographic 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.