JPH05323494A - Supporting body for photographic printing paper - Google Patents

Abstract

(57) [Summary] (Modified) [Purpose] To improve the adhesion between layers in a photographic paper support having a surface resin coating layer of a multilayer structure composed of a cured product of a resin that is cured by electron beam irradiation. And suppresses yellowing in the developing process. [Structure] The resin coating layer provided on the surface of the sheet-shaped substrate 11 is a resin coating layer having a multilayer structure composed of a cured body of a resin that is cured by electron beam irradiation, and the outermost layer of the resin coating layer is a molding substrate. On the 5th surface, an electron beam is irradiated in an atmosphere having an oxygen concentration of 600 ppm or more to cure and form.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION The present invention relates to a photographic paper support. More specifically, the present invention is
The present invention relates to a photographic printing paper support having a multi-layered surface resin coating layer made of a cured product of a resin that is cured by being irradiated with an electron beam (hereinafter referred to as an electron beam curable resin). The adhesion between the layers of the support is improved, and yellowing that occurs during the development process is prevented.

[0002]

2. Description of the Related Art Conventionally, so-called baryta paper has been used as a support for photographic printing paper, which is coated with a white pigment such as barium sulfate on both sides of paper which has been given strong size and high strength. It is manufactured by However, in recent years, instead of the baryta paper, a polyolefin resin-coated support produced by coating both surfaces of a substrate made of paper with a polyolefin resin has been widely used. In such a support, since the polyolefin coating layer is hydrophobic, the processing liquid is less likely to penetrate into the support during the developing and fixing process as compared with the baryta paper, and thus the washing time and the drying time are significantly increased. Since it has the advantage of being shortened, and since the treatment liquid does not penetrate into the paper substrate, it has advantages such as expansion and contraction of the support itself and excellent dimensional stability.

However, in order to improve the hiding power or resolution, it is necessary to mix an inorganic white pigment such as titanium dioxide in the polyolefin resin coating layer of such a support. However, there is a problem in that the dispersibility in the resin is poor, and the volatile components contained in the pigment foam in the melt extrusion process, causing film cracking in the resin coating layer. For this reason, there is a limit to the amount of pigment that can be added to the resin coating layer. Generally, when titanium dioxide is used, it is difficult to add a large amount of pigment, exceeding about 20% by weight. The photographic printing paper obtained by using such a conventional photographic printing paper support cannot be said to be sufficiently satisfactory in image sharpness.

In recent years, a support for photographic printing paper has been proposed which has an electron beam curable resin coating layer obtained by coating an electron beam curable resin on a support and irradiating it with an electron beam for curing. (For example, Japanese Patent Publication No. 60-17104, Japanese Patent Publication No. 60
-17105, JP-A-57-49946, etc.). According to this method, it is not necessary to heat the resin composition to a high temperature when forming the resin coating layer, and the pigment content is 20 to 8
The image sharpness of photographic papers obtained with such supports can be increased up to 0% by weight.
Compared with polyolefin resin coated photographic printing paper, it is significantly improved.

However, in a photographic printing paper produced by providing a photographic emulsion layer on the electron beam-curable resin coating layer as described above, development processing chemicals are adsorbed on the resin coating layer and remain in the photographic developing process. , Phenomenon of yellowing after development, that is, yellowing occurs, and if it is developed after being stored for a long period of time, fog occurs to a degree that cannot be ignored as a product, or the sensitivity changes. It turns out that there is a case to do.

Various improvement methods have been proposed in order to solve these problems. For example, Japanese Patent Publication No. 1-21495 discloses a method for suppressing a change in sensitivity during storage of an electron beam curable resin coating layer. A method of providing a polyethylene resin coating layer on the above is disclosed. However, in this method, the effect of reducing fog is not recognized unless the thickness of the polyethylene resin coating layer is increased, and the polyethylene resin coating layer containing a relatively small amount of pigment covers the surface of the electron beam curable resin coating layer. Therefore, there is a problem in that the improvement in image sharpness, which is one of the merits when using the electron beam curable resin, must be sacrificed.

Further, Japanese Patent Application Laid-Open No. 60-144736 discloses that
A method has been proposed in which a shielding layer is provided between the base paper and the electron beam curable resin coating layer to suppress changes in photographic sensitivity that occur during storage. However, the materials proposed here as the material for forming the shielding layer are still insufficient in terms of preventing fog during long-term storage.

Further, JP-A Nos. 62-61049 and 62-141543 propose methods for preventing fog and yellowing by using a specific polymer or monomer as an electron beam curable resin. However, even if these methods are used, sufficiently satisfactory results have not been obtained.

Among the above problems, as a method of preventing fogging, the present inventors have already proposed a method of supporting a magnesium compound on the base paper when producing the base paper for a support. There is.

As a method of preventing yellowing, a support for photographic printing paper having a laminated structure of two or more surface resin coating layers has been proposed. Such a photographic printing paper support has a resin coating layer previously cured on the surface of the molded body,
It is obtained by laminating with a resin coating layer provided on a sheet-shaped substrate, and further curing and integrating. However, although the photographic printing paper support having such a structure is effective in preventing yellowing, the cross-linking density of the resin is increased by the irradiation of the electron beam, and the structural difference between the layers of the laminated resin coating layers is increased. There is a new problem that an interface is generated and the adhesion between the layers becomes insufficient, resulting in delamination during development processing.

[0011]

SUMMARY OF THE INVENTION The present invention solves the above-mentioned drawbacks of a support for photographic printing paper provided with an electron beam-curable resin coating layer, suppresses yellowing during development processing, and has a suitable degree. Another object of the present invention is to provide a photographic paper support having excellent flexibility and good adhesion between the layers.

[0012]

DISCLOSURE OF THE INVENTION The inventors of the present invention have conducted extensive studies to solve the above problems of a support for photographic printing paper having an electron beam curable resin coating layer, and as a result, a photographic emulsion layer. The surface resin coating layer on the side provided with is formed into a multilayer structure of two or more layers, and the outermost resin coating layer in contact with the photographic emulsion layer is irradiated with an electron beam on the molding surface in an atmosphere with a relatively high oxygen concentration. The present invention has been completed by finding that a support for photographic printing paper can be obtained in which the adhesion between layers is good and the yellowing is suppressed by curing and forming.

That is, the support for photographic printing paper of the present invention comprises a sheet-shaped substrate, a surface resin coating layer formed on the surface of the sheet-shaped substrate on which the photographic emulsion layer is formed,
A backside resin coating layer formed on the other side surface of the sheet-shaped substrate, wherein the front surface resin coating layer comprises a cured body of a resin that is cured by irradiation with an electron beam. It is characterized in that it is composed of a laminate of more than one layer, and that the outermost layer thereof is cured by electron beam irradiation in an atmosphere having an oxygen concentration of 600 ppm or more on the molding surface.

[0014]

In a specific method for producing the photographic printing paper support of the present invention, first, the electron beam curable resin for forming the outermost layer of the surface resin coating layer is added to the cast surface (molding surface) of the molding substrate. Coated on top, then oxygen concentration is 600ppm
In the atmosphere described above, this is irradiated with an electron beam and cured to form the outermost resin layer.

Separately from this, an electron beam curable resin is applied on the surface of the sheet-like base material to form a coating layer, and this coating layer and
The outermost layer is laminated on the molding substrate, electron beams are again irradiated on the molding substrate to cure it, and both layers are integrated, and then, this is peeled from the molding surface. By doing so, the support for photographic printing paper of the present invention having good interlayer adhesion and improved yellowing resistance can be produced.

The support for photographic printing paper of the present invention produced by the above method has good interlayer adhesion and improved yellowing prevention property for the following reason. First, the reason why the resin coating layer turns yellow in the development processing step is that the developing agent contained in the development processing liquid is adsorbed to the resin coating layer and is oxidized and colored. Therefore, in order to prevent yellowing, the crosslinking density of the outermost resin coating layer may be increased and the adsorption of the developing agent to the outermost resin coating layer may be reduced. However, if the crosslinking density of the outermost resin coating layer is increased, the bonding force between the outermost resin coating layer and the resin layer applied on the surface of the sheet-shaped base material is lowered, and as a result, the interlayer adhesiveness is deteriorated.

When the electron beam curable resin is cured by irradiation with an electron beam, the polymerization reaction is hindered by the presence of oxygen. Therefore, nitrogen gas is generally refluxed to perform the reaction in an atmosphere with a low oxygen concentration. It is being appreciated. Therefore, when the electron dose is the same, when the oxygen concentration is high, the polymerization reaction of the electron beam curable resin is inhibited as compared with the case where the oxygen concentration is low, the crosslink density of the resin is suppressed to that low, and the bond strength between layers is reduced. Is lessened, and a resin coating layer having good adhesiveness can be obtained.

In the present invention, as described above, when forming the outermost layer, the electron beam curable resin is applied onto the molding surface, and then the applied layer is applied to the applied layer in an atmosphere having a high oxygen concentration of 600 ppm or more. It is irradiated with an electron beam and cured, whereby the outermost layer is formed. In this case, the surface of the outermost layer that is in contact with the molding surface (hereinafter referred to as the outermost layer surface) is the surface on the other side, that is, the surface that is exposed to the atmosphere with a high oxygen concentration (hereinafter, the outermost surface). Compared with the outer layer back surface), since there is an oxygen-free state, or the oxygen concentration is extremely low, a difference in crosslink density occurs between the outermost layer surface portion of the outermost layer to be formed and the outermost layer back surface portion, The outermost layer surface portion has a higher crosslink density than the outermost layer rear surface portion.

That is, the outermost layer surface of the outermost layer formed is the surface which comes into contact with the developing solution in the developing step, but since it is formed of a hard and dense resin, it does not adsorb the developing agent, Therefore, yellowing is prevented. On the other hand, the back surface of the outermost layer is a surface to be bonded to another resin coating layer, but since it is formed of a resin having a low cross-linking density, it has extremely good adhesiveness to another resin layer.

As described above, the support for photographic printing paper of the present invention has different cross-linking densities in the front and back portions of the outermost layer of the surface resin coating layer so that the interlayer adhesiveness and yellowing prevention can be prevented. It has improved both sex. Therefore,
In the present invention, as the electron beam curable resin used for forming the surface resin coating layer, it is advantageous to use a resin having many functional groups capable of obtaining a high crosslink density in the outermost layer, and other For the resin layer, it is preferable to use a resin having a small number of functional groups so as to form a resin having a low crosslink density and good flexibility.

The electron beam curable resin used for forming the surface resin coating layer of the present invention can be selected from the following compounds. (1) Aliphatic, alicyclic and araliphatic 1 to 6 valent alcohol and polyalkylene glycol acrylate compounds (2) Aliphatic, alicyclic and araliphatic 1 to 6 valent Acrylate compounds obtained by adding alkylene oxide to alcohol (3) Polyacryloylalkyl phosphates (4) Reaction products of carboxylic acid, polyol and acrylic acid (5) Isocyanate, polyol and acrylic Reaction products with acid (6) Reaction products with epoxy compound and acrylic acid (7) Reaction products with epoxy compound, polyol and acrylic acid

More specifically, the electron beam curable resin is polyoxyethylene epichlorohydrin-modified bisphenol A diacrylate, dicyclohexyl acrylate, epichlorohydrin-modified polyethylene glycol diacrylate, 1,6-hexanediol diacrylate, hydroxybivalic acid. Ester neopentyl glycol diacrylate, nonylphenoxy polyethylene glycol acrylate, ethylene oxide modified phenoxyphosphoric acid acrylate, ethylene oxide modified phthalic acid acrylate, polybutadiene acrylate,
Caprolactane-modified tetrahydrofurfuryl acrylate, tris (acryloxyethyl) isocyanurate,
Trimethylolpropane triacrylate, pentaerythritol triacrylate, pentaerythritol tetraacrylate, dipentaerythritol hexaacrylate, polyethylene glycol diacrylate,
It is preferably selected from 1,4-butadienediol diacrylate, neopentyl glycol diacrylate, neopentyl glycol-modified trimethylolpropane diacrylate, and the like.

In the present invention, these resins may be used alone, or two or more of these resins may be used in combination, but as the resin used for forming the outermost layer, It is advantageous to use a resin with 4 or more functional groups to give a high crosslink density,
A resin having 1 to 3 functional groups is preferably used for the other resin layers.

The surface resin coating layer of the present invention preferably contains a white pigment in order to improve the sharpness of an image when used as a photographic paper. Titanium dioxide is mainly used as the white pigment, but in addition to this, barium sulfate, calcium carbonate, aluminum oxide, zinc oxide,
Any of magnesium oxide and the like can be used.

The content of the white pigment is preferably 20 to 80% by weight of the total solid content of the surface resin coating layer.
If the content is less than 20% by weight, the sharpness of the photographic image on the photographic paper obtained may not be sufficient, and it is 8
When it exceeds 0% by weight, the flexibility of the obtained resin coating layer is lowered, and film cracking may occur.

To disperse the white pigment in the electron beam curable resin as described above, a three-roll mill (three-roll mill), a two-roll mill (two-roll mill), a cowles dissolver, a homomixer, a sand grinder, a planetar. Lee mixer, ultrasonic disperser and the like can be used.

As the method for applying the resin composition to the molding surface or the surface of the sheet-shaped substrate, for example, bar coating method, air doctor coating method, blade coating method, squeeze coating method, air knife coating method, roll coating Method, gravure coat method and transfer coat method can be used. For this purpose, a fountain coater or slit die coater system can be used. Especially when using the surface of the metal cylindrical rotating body as the surface of the molding substrate, a roll coating method using a rubber roll or an offset gravure coating method is used in consideration of preventing damage to the molding surface. Further, a non-contact type fountain coater, a slit die coater method or the like is also advantageously used.

The coating amount of the surface resin coating layer of the present invention is preferably adjusted so that the coating amount after curing is ² to 60 g / m ² .

In the present invention, the electron beam accelerator used for electron beam irradiation may be any one of a van de Graaff type scanning system, a double scanning system and a curtain beam system, but a curtain beam which is relatively inexpensive and has a large output. The system is advantageously used. The acceleration voltage during electron beam irradiation is preferably 100 to 300 kv, and the absorbed dose is 0.1 to 6 Mr.
It is preferably ad, and particularly preferably 0.2 to 4 Mrad. However, since it is not necessary to consider deterioration of the sheet-shaped substrate for curing the outermost layer formed on the molding surface, it is possible to use a higher dose.

In the present invention, when the outermost layer of the surface resin coating layer is formed, the coating layer is irradiated with an electron beam in an atmosphere having an oxygen concentration of 600 ppm or more, preferably 1000 ppm or more to form an electron beam curable resin. Cure. In this case, the type and concentration of the coexisting gas, the temperature and the humidity of the atmosphere are not particularly limited, and coexisting with an inert gas such as nitrogen is acceptable.

Next, an apparatus used for forming the surface resin coating layer of the present invention will be described with reference to the accompanying drawings.

In FIG. 1, the electron beam curable resin composition 3 for forming the outermost layer is formed from a paint container 2 using a coater 4a, 4b such as an offset gravure coater to form a molding base 5 made of a metal drum. It is applied on the surface and cured by an electron beam emitted from the first electron beam irradiation device 6 to form a cured film 7. At this time, the electron beam irradiation in the first electron beam irradiation device 6 is performed in an atmosphere having an oxygen concentration of 600 ppm or more, preferably 1000 ppm or more. On the other hand, the electron beam curable resin composition 9 in the container 8 is
The coater 10a, 10b, 10c is used to coat the sheet-shaped substrate 11 to form a coating layer 12. Then
The coating layer 12 is guided by the guide roll 13 onto the molding substrate 5 made of a metal drum and bonded to the cured film 7, and is cured and combined by electron beam irradiation from the second electron beam irradiation device 14. As a result, a surface resin coating layer is formed, and thereafter, the support 16 for photographic printing paper produced in the above process is separated from the molding base 5 via the guide roll 15.

FIG. 2 shows an embodiment in which a film is used as a molding substrate. In the product of FIG. 2, instead of the metal drum 5, the surface of a polymer film 17 such as a polyester film is used as a molding surface. Also in this case, as in the case of FIG. 1, the first electron beam irradiation is performed in an atmosphere of high oxygen concentration, that is, 600 pp.
It is carried out in an atmosphere having an oxygen concentration of m or more, preferably 1000 ppm or more. Further, the second electron beam irradiation may be applied through the molding film 17 as shown in FIG. 2, or may be applied from the back surface of the sheet-shaped substrate 11 on the side opposite to the molding film 17. Good. Although the molding film 17 is repeatedly used after being wound up, it may have an endless belt shape. The molding film 17 is not necessarily a polymer film, and may be a belt-shaped metal film, and the metal film may be an endless belt.

In both cases of FIG. 1 and FIG. 2, the outermost layer, the cured film 7, is irradiated twice with the electron beam, so that the crosslink density of the film is increased and the yellowing in the developing process is suppressed. Furthermore, water resistance and gloss are imparted.

The backside resin coating layer of the present invention is advantageously formed of a film-forming synthetic resin such as a polyolefin resin which has been conventionally used for producing a support for photographic printing paper. Further, it may be formed of the above-mentioned electron beam curable resin or the like.

In the present invention, the polyolefin resin for forming the backside resin coating layer is ethylene,
Alternatively, it can be selected from α-olefins, for example, homopolymers of propylene and the like, copolymers of at least two of the above ethylene and α-olefin, and a mixture of at least two of these various polymers. Particularly preferred polyolefin resins are low density polyethylene, high density polyethylene, linear low density polyethylene, and mixtures thereof. The molecular weight of the polyolefin resin is not particularly limited, but one having a molecular weight of 20,000 to 200,000 is usually used. These resins are coated by a usual melt extrusion coating method to form a backside resin coating layer.
Moreover, a small amount of an antioxidant and a lubricant may be added to the polyolefin resin, if necessary.

When an electron beam-curable unsaturated organic compound is used for forming the backside resin coating layer, all the compounds used for forming the frontside resin coating layer can be used. Further, the method of forming the back surface resin coating layer is the same as in the case of the above-mentioned front surface resin coating layer. The weight of the backside resin coating layer is not particularly limited, but is usually preferably in the range of 10 to 40 g / m ² .

The sheet-like base material used in the present invention is a base paper generally used for the production of a photographic support, that is, a base paper having natural pulp as a main component and having a high whiteness and a smooth surface. Advantageously used.

As the natural pulp for forming the base paper, generally, those containing, as a main component, softwood pulp, hardwood pulp, softwood mixed hardwood pulp, etc. are advantageously used. Further, the base paper may contain additives such as a sizing agent, a fixing agent, a paper strengthening agent, a filler, an antistatic agent, a pH adjusting agent, a pigment and a dye, which are generally used in papermaking. Further, a surface sizing agent, a surface paper strength agent, an antistatic agent, etc. may be appropriately applied to the surface. In addition, a magnesium compound may be supported for the purpose of preventing fog that occurs during long-term storage when used as photographic paper.

Further, in the present invention, a plastic film or so-called synthetic paper may be used as the sheet-shaped substrate without any problem. For example, a film formed by a melt extrusion method of a thermoplastic resin composition containing a polyolefin resin such as polypropylene resin or polyethylene resin can also be used. In addition, for plastic films and synthetic papers used as sheet-shaped substrates, pigments such as clay, talc, kaolin, calcium carbonate, titanium dioxide and magnesium hydroxide, metallic soaps such as zinc stearate and various surfactants, etc. The dispersant, colored pigment, etc. may be included.

[0041]

The present invention will be described in more detail with reference to the following examples, which should not be construed as limiting the invention thereto.

Example 1 A base paper having a basis weight of 180 g / m ² was used as a sheet-like base material, and one side thereof was subjected to an activation treatment by corona discharge, and then a polyethylene resin was applied thereto at a coating amount of 30 g. / M
^Then, the backside resin coating layer was formed by coating by extrusion coating so as to be ² .

Next, an outermost layer-forming electron beam-curable resin composition having the following composition was coated with a paint conditioner 1
After being mixed and dispersed for a period of time, this composition was applied onto the surface of a molding substrate made of a chromium-plated metal plate,
Apply with a wire bar so that the coating amount after curing is 5 g / m ² , and the oxygen concentration is 600 pp in this coating layer.
m atmosphere, accelerating voltage: 165 kv, absorbed dose: 3
The outermost layer was formed by irradiating an electron beam under the condition of Mrad to cure it.

The outermost layer forming the electron beam curing resin composition Ingredient weight pentaerythritol oligomer 80 parts by weight (trademark: Beam Set 700, Arakawa Chemical Industries, Ltd.) Titanium dioxide (trademark: A220, manufactured by Ishihara Sangyo Kaisha) 20 parts by weight

Separately from this, an electron beam curable resin composition having the following composition was prepared by mixing and dispersing for 1 hour with a paint conditioner, and then this composition was applied to the side of the base paper on which the backside resin coating layer was not provided. Is coated on the surface of the above with a wire bar so that the coating amount after curing becomes 20 g / m ² , and this coating layer is applied onto the surface of the above-mentioned metal plate-forming substrate and laminated to the outermost layer cured. The coating layer was cured by irradiating it with an electron beam from the back side of the base paper under the conditions of an accelerating voltage of 175 kv and an absorbed dose of 1.5 Mrad to form a surface resin coating layer united with the outermost layer. The photographic printing paper support was peeled off from the surface of the metal plate forming substrate.

The electron beam-curable resin composition Ingredient weight urethane acrylate oligomer 36 parts by weight (trademark: Beam Set 550B, manufactured by Arakawa Chemical Industries) 2-functional acrylate monomer 24 parts by weight (trademark: M-220, manufactured by Toagosei ) Titanium dioxide 40 parts by weight (trademark: A220, manufactured by Ishihara Sangyo)

Example 2 By the same operation as in Example 1, a support for photographic printing paper was prepared. However, the electron beam curable resin composition for forming the outermost layer was cured in an atmosphere with an oxygen concentration of 1000 ppm.

Example 3 A photographic printing paper support was prepared in the same manner as in Example 1. However, the electron beam curable resin composition for forming the outermost layer was cured in the atmosphere.

Comparative Example 1 A photographic printing paper support was prepared in the same manner as in Example 1. However, the electron beam curable resin composition for forming the outermost layer was cured in an atmosphere with an oxygen concentration of 500 ppm.

Comparative Example 2 By the same operation as in Example 1, a support for photographic printing paper was prepared. However, the electron beam curable resin composition for forming the outermost layer was cured in an atmosphere having an oxygen concentration of 100 ppm.

Comparative Example 3 By the same procedure as in Example 1, a support for photographic printing paper was prepared. However, without curing the coating layer of the electron beam curable resin composition for forming the outermost layer, after laminating it with the resin layer coated on the base paper surface, it is irradiated with an electron beam and cured to form a metal plate. It was peeled off from the surface of the substrate to prepare a support for photographic printing paper.

Performance Test The support for photographic printing paper obtained in each of Examples 1 to 3 and Comparative Examples 1 to 3 was tested and evaluated for its adhesion and anti-yellowing property. However, the evaluation of adhesiveness and yellowing was performed as follows. 1. Adhesiveness: Cellophane tape was attached to the surface of the electron beam-curable resin coating layer of the test support, and the peeled state of the resin coating layer when the tape was peeled off was observed and evaluated. The resin coating layer was not peeled at all, and was evaluated as ◯, the case where the outermost layer was partially peeled was evaluated as Δ, and the case where the outermost layer was completely peeled was evaluated as x.

2. Yellowing due to development processing: A test support was used as a Dust automatic developing machine (trademark: RCP20, made by Dust Company).
Development processing using the TAPPI color tone before and after the development processing.
The value was measured according to the method of -T524, and the value (Δb value) obtained by subtracting the b value before the development processing from the b value after the development processing was evaluated as an index of yellowing.

The test results are shown in Table 1.

[0055]

[Table 1]

[0056]

EFFECT OF THE INVENTION The support for photographic printing paper of the present invention prevents a drawback in the case where a coating layer made of an electron beam curable resin is provided, that is, prevents the coating film from yellowing during the development process, and prevents the resin coating layer. This is because it retains the flexibility and prevents the adhesion failure between the respective layers which occurs when the resin coating layer has a multilayer structure of two or more layers, and is extremely effective in practice.

[Brief description of drawings]

FIG. 1 is a process explanatory view showing an example of a method for manufacturing a support for photographic printing paper of the present invention.

FIG. 2 is a process explanatory view showing another example of the method for producing a support for photographic printing paper of the present invention.

[Explanation of symbols]

 1 ... Coating liquid coating and curing equipment 2 ... Paint container 3 ... Electron beam curable resin composition 4 ... Coater 5 ... Molding substrate 6 ... First electron beam irradiation device 7 ... Cured film 8 ... Paint container 9 ... Electron beam curable Resin composition 10 ... Coater 11 ... Sheet-shaped substrate 12 ... Coating layer 13 ... Guide roll 14 ... Second electron beam irradiation device 15 ... Guide roll 16 ... Photographic paper support 17 ... Molding film

Continuation of front page (51) Int.Cl. ⁵ Identification number Office reference number FI technical display location D21H 19/20 25/00 27/00 7199-3B D21H 5/00 Z

Claims (1)

[Claims] 1. A sheet-shaped substrate, and the sheet-shaped substrate,
A surface resin coating layer formed on the surface on which the photographic emulsion layer is formed, and a back surface resin coating layer formed on the surface on the other side of the sheet-shaped substrate, The coating layer is
It is a laminate of at least two layers made of a cured product of a resin that is cured by irradiation with an electron beam, and its outermost layer is cured by electron beam irradiation in an atmosphere having an oxygen concentration of 600 ppm or more on the molding surface. A support for photographic printing paper, characterized in that