JPS59198444A - Method for accelerating hardening of photographic layer - Google Patents

Abstract

PURPOSE:To uniformly raise film strength of a photographic layer in a short period by irradiating microwaves on a layer obtained by applying a fluid contg. a protective colloid and its hardening agent to a support and drying it. CONSTITUTION:A fluid composed of a protective colloid and its hardening agent is applied to a support and dried to obtain a photographic layer, and it is irradiated with microwaves to accelerate its hardening.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of accelerating the curing of a protective colloid layer containing a curing agent, and more particularly to a method of accelerating the curing of a photographic layer of a photographic material.

Various photographic layers forming a photographic material, such as a silver halide emulsion layer, an antihalation layer, a banking layer, a filter layer, an intermediate layer, an undercoat layer, a protective layer, an image-receiving layer used in the silver complex diffusion transfer method, etc. Generally, various hydrophilic colloids such as gelatin, polyvinyl alcohol, and polyacrylamide are used as protective colloids.

A silver image or a pigment surface pattern can be obtained on a photographic material having these photographic layers on a support through a process, but these photographic processes are performed using a high pII liquid, a low pII liquid, Alternatively, it may be carried out by immersing the photographic material in a high temperature liquid or the like. It is well known that photographic materials need to have increased physical strength so that the photographic layers are not easily damaged during processing or other handling.

As a method of increasing the film strength of the photographic layer, it is common practice to incorporate a hardening agent (also referred to as a hardening agent) for the protective colloid forming the photographic layer into the protective colloid. Hardeners include aldehyde hardeners such as formaldehyde and glyoxal, vinyl sulfone hardeners, Epoquine hardeners, aziridine hardeners, active rogen hardeners, and incyanate hardeners. Various agents are known. These hardeners are usually added to the coating solution before coating the photographic layer system on the support, and at least when the coating layer is coated, dried, and wound up on the core. The membrane strength has been reached to the extent that it can withstand the pressure and tension applied to the photographic layer. However, in photographic coatings immediately after coating and drying, the hardening agent usually remains in an unreacted state with the binder, and the film strength is not sufficient to withstand photographic processing. These unreacted hardeners will continue to react, albeit gradually, even after the photographic layer is coated and dried, so if the photographic material is left for a long period of time before being shipped, the film will have the strength to withstand photographic processing. However, such long-term open W not only reduces productivity, but also requires a huge amount of storage space, makes it impossible to control the reaction of the hardening agent, and causes deterioration of photographic properties over time. There is.

As a method to eliminate all of these disadvantages, photographic materials that should normally be stored at a cold temperature can be stored for a short period of time at a high
A method of accelerating the reaction between the unreacted hardener and the protective colloid in the photographic layer by raising the temperature of the photographic layer by placing it under an appropriate temperature and humidity of 0 to 50°C and 40 to 70% RJ-1. There is. This method has the advantage of eliminating the above-mentioned disadvantages and increasing the film strength of the photographic layer to a certain practical level in a short period of time.

However, this method has the following drawbacks. Part 1
First, in order to raise the temperature of the photographic layer, if the photographic material is placed in a semi-finished state (so-called mill roll state) after coating and drying, or in a packaged state under high temperature, It takes a long time for all the photographic layers in one packaging unit to reach a certain temperature level, and during this time the reaction of the hardening agent occurs between the photographic layers whose temperature rose earlier and the photographic layers whose temperature rose later. A phenomenon occurs in which there are differences in degree and film strength. For example, in the case of roll products, the outside and inside of the roll, in the packaged state, the parts with different heat absorption capacities for each packaging unit, and whether a large amount of products are rolled or packaged, are exposed to high temperatures at the same time. When placed, the result is that the film strength differs depending on the arrangement state.

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for accelerating curing that can uniformly cure a photographic layer formed on a support in a short period of time.

Another object of the present invention is to provide a method for accelerating curing, which allows a photographic layer formed on a support to have a uniform and high film strength in a short period of time.

The object of the present invention is achieved by coating a composition containing a protective colloid and a curing agent for the protective colloid on a support, drying the resulting photographic layer, and irradiating the resulting photographic layer with microwaves.

The microwave used in the present invention refers to electromagnetic waves with a frequency of several MHz or more in alternating current, but usually 3 to 3 MHz.
000 M I (using microwaves of z).

In the present invention, photographic layers include photosensitive layers such as silver halide emulsion layers, various non-photosensitive layers that do not contain silver halide, and physical development nuclei used in the silver complex diffusion transfer method. Refers to all forming layers provided on a support to form a photographic material, including image-receiving layers.

The retained colloids according to the present invention include ceratin, derivative gelatin, polyvinylalconope polyvinylpyrrolidone, polyacrylamide, styrene-maleic anhydride copolymer, imbutylene-maleic anhydride copolymer, methyl vinyl ether-maleic anhydride. Copolymers, polyvinyl methyl ether, carboxymethyl cellulose, hydroxyethyl cellulose, acrylic acid-ethyl acrylate copolymer, storum alginate, casein, albumin, and other protective colloids conventionally known as binders for photographic layers are used. Seratin or a warm system of seratin and other protective colloids are typically used.

The curing agent according to the present invention includes aldehyde compounds such as formaldehyde, glyoxal, and glutaraldehyde, U.S. Pat.
．． 303, British Patent No. 974.723, British Patent No. 1,167,
207, etc., ketone compounds such as diacetyl and cyclopentanedione, bis(2-chloroethylurea), ゛2
-Hydroxy-4,6-dichloro-1,3,5-triazine, divinylsulfone, 5-acetyl-1°3-diacryloyl, hexahydro-], 3,5-triazine, U.S. Patent No. 3,635,718, 3゜232,7
63, compounds with reactive olefins described in British Patent No. 994.8.09, etc., N-hydroxymethylphthalimide, and other U.S. Patent No. 2.732.3
16, N- described in 2.586.168 etc.
Methylol compounds, incyanates described in U.S. Patent No. 3,103,437, etc., U.S. Patent No. 3.0
17°280, 2,983,611, etc., U.S. Patent No. 2.725.294
, acid derivatives described in U.S. Patent No. 2.725.295, etc., carbodiimide compounds described in U.S. Patent No. 3,100,704, etc., U.S. Patent No. 3,091,53
Epoxy compounds described in U.S. Patent No. 7, etc.
, 321, 313, 3,543, 292, etc., inoxazole compounds such as mucochloric acid, dioxane derivatives such as dihydroxydioxane, dichlorodioxane, chromium alum, Examples include inorganic hardeners such as zirconium sulfate and chromium trichloride. These hardening agents may be used alone or in combination, and 1 may be used in an amount of 0.01 to 100% by weight, preferably 0.1 to 10% by weight, based on the dry weight of the protective colloid.
It is used in the range of weight-male%. The hardening agent can be added at any stage up to the application of the photographic coating solution by adding a hardening agent solution to the protective colloid-containing solution. When added to a silver halide emulsion, it is usually added after ripening and before coating.

As the microwave irradiation device used in carrying out the present invention, a batch oven type device, a conveyor type device, a meandering waveguide type device, etc. can be used.

When heating by microwave irradiation, the irradiated object itself becomes a heating element. By selecting the moisture content, frequency, output, irradiation time, etc., it is possible to uniformly raise the surface and internal temperature of the irradiated object. Even when heated, the conventional difference in the degree of dura mater progression due to the time lag in temperature rise is eliminated, and a photographic layer always having uniform film strength can be obtained.

A typical embodiment of the present invention involves raising the temperature of the photographic material briefly and uniformly by microwave irradiation to a predetermined reaction temperature, followed by conventional Al is a method of heating by radiation, convection, and conduction. When irradiating photographic materials with microwaves in the form of rolls, chips, or products, it is appropriate to use a batch oven-type device, but when irradiating microwaves while unwinding a roll-like material, a conveyor-type device or It is suitable to use a meandering waveguide type device.

In another embodiment of the present invention, a fast-acting hardener or a fast-acting hardening system (a combination of a fast-acting protective colloid and a hardening agent), or a photograph in which high film strength is not required. In the case of layers, it is also possible to heat only by microwave irradiation instead of conventional heating methods.

Next, examples of the present invention will be shown, but the present invention is not limited thereto.

EXAMPLE One side of a support made of paper having a water content of about 7% and covered with polyethylene layers on both sides was subjected to corona discharge treatment, and then a gelatin/silver halide emulsion layer was completely coated and dried. The emulsion layer contained 0.6% by weight of formalin as a hardening agent for gelatin.

The obtained long photographic paper had an inner diameter of 76 ml and an outer diameter of 88 mL.
The cylindrical paper core has a width of 215i* and a diameter of 200cm.
It's rolled into a roll. When this roll of photographic paper (hereinafter simply referred to as one roll of photographic paper) was heated with a batch open type microwave irradiation device at both internal and external temperatures of 145°C, after 2 minutes Both the surface temperature and internal temperature reached 40°C±1.0°C. Subsequently, conventional radiation and convection heating was performed at 40°C for 3 days, and the melting point of the surface of the emulsion layer of the photographic paper and the film strength of the emulsion layer were measured, and the results are shown in the table below. When conventional heating by radiation and convection was used for 3 days without microwave irradiation, the surface temperature was 40°C ± 0.0°C.
5°C was reached, but the internal temperature was 36°C. Similarly, the measurement results of the degree of hardness are shown in the table below.

In this example, the internal temperature refers to the thickness of the long photographic paper wound around the core, that is, the temperature at the center between the surface of the photographic paper roll and the surface of the core, and at the center of the photographic paper. .

Table (Note 1) Cut out a part of the surface and inside to use as a sample, immerse the sample in a developer having the following composition, gradually heat the developer, and the temperature of the developer when the emulsion film begins to melt. was taken as the melting point (°C).

(Note 2) Immerse the above sample at 20°C for 2 minutes a L
After that, a ball point needle with a diameter of 0.5 opening was placed perpendicular to the surface of the sample membrane, and when a load was applied and the surface of the embryo material was moved in parallel at a speed of ICm 7 seconds, the load caused nif-prone on the surface of the sample membrane. (9) was taken as the film strength.

Developer water 750mJ Metol 180g Hydroquinone
4.09 Sodium sulfite
15.0.9 Sodium carbonate (monohydrate) 2
6.7jl Potassium Bromide 0.19
Add water 1. Let it be OOQmr.

As shown in the table above, when microwave irradiation is performed, uniform hardness can be obtained on both the surface and inside of the photographic paper roll, but when microwave irradiation is not performed, a difference in hardness occurs between the surface and the inside, resulting in uniform hardness. It can be seen that hardness cannot be obtained. It took 5 days for the surface and internal hardness to reach a substantially uniform state without microwave irradiation.

Similar results were obtained for color photographic paper and image-receiving materials for silver complex diffusion transfer, and similar results were obtained when heated in the form of product packaging.

Procedural Amendment (Import) 1, , Display of JY Showa 3deltail-W Permit 19f1 No. 73+OX
2. Name of the invention → -114-Nori F"l Jiri Nib Otsushi E J Rejection 3. Relationship with the case of the person making the amendments, 1 person 4 Residence of the agent 〒 100 Tokyo 1st Generation 110th Ward Marunouchi-Ra-11
4+% No. 2 Mitsubishi Paper Mills Co., Ltd. (1, Showa, Month, Day 8, Contents of amendment '1) Sekima, D + Naicha...Kai 7 on the last day.

Claims (1)

[Claims] A method in which a composition containing a protective colloid and a curing agent for the protective colloid is applied onto a support, and the resulting photographic layer is irradiated with microwaves to accelerate the curing of the photographic layer.