JPH04323651A - Manufacture of silver complex salt diffusion transfer image receiving material - Google Patents

Abstract

PURPOSE:To provide the silver complex diffusion transfer image receiving material high in reflection density. CONSTITUTION:A support having a rough surface is coated with an oil high in boiling point containing an emulsion dispersion of an oil-soluble fluorescent whitening agent in an amount of from its saturated solubility at 50 deg.C to 4 times as high as this and/or a coating fluid for forming an adjacent layer, and dried raising its wet-bulb temperature to >=23 deg.C until the gelatin concentration of the coating layer at latest to about 30wt.%.

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 silver complex diffusion transfer material by combining a light-sensitive material and an image-receiving material, and more particularly to a method for producing an image-receiving material.

0002

[Prior Art] The silver complex diffusion transfer method generally uses a photosensitive material in which a silver halide emulsion layer is formed on a support as a photosensitive layer, an image receiving material in which an image receiving layer containing physical development nuclei is formed on a support, and It consists of a processing solution containing a silver halide solvent. The principle of the silver complex diffusion transfer method is that the silver halide in the exposed areas of the exposed photosensitive layer is developed by a processing solution or a developing agent in the photosensitive material, and at the same time, the silver halide in the unexposed areas is developed by the halogen in the processing solution. It reacts with a silver oxide solvent to form a soluble silver complex salt, which diffuses into the image-receiving material and deposits on physical development nuclei in the image-receiving layer to form a silver image.

[0003] The silver complex diffusion transfer method based on such a principle is widely used for copying documents and as a plate material for plate-making operations. The important qualities of the image-receiving material used in the silver complex diffusion transfer method are high silver image density (reflection and transmission density), good color tone (reflection and transmission) (generally a blue-black tone is desired), and a fast diffusion transfer speed. In addition, the image-receiving layer must have sufficient film strength.

Especially silver image density (reflection and transmission density)
is an extremely important quality, and it is said that high image density is desirable in order to reproduce good image quality (fine lines and netting) when used as a printing material.

[0005] Also, the color tone of the silver image is blue-black.
It is considered to be a very important quality in recent years.

Furthermore, high whiteness is required as an important quality of the image-receiving material. The choice of use of this brightener also affects the quality of the silver image, as shown in JP-A-1-246539. Also, JP-A-60-6
As shown in Japanese Patent Application No. 3535, it is known that the drying conditions of the coating solution for forming the image-receiving layer affect the quality of the silver image in the case of a rough surface support, but when an oil-soluble optical brightener is used. There is a big difference in quality depending on the conditions of use.

As described above, there is a need for a method of using a fluorescent brightener that provides high silver image density and improves white background in the silver salt diffusion transfer method, but it is not yet sufficient at present.

[0008]

SUMMARY OF THE INVENTION An object of the present invention is to provide a method for using a fluorescent whitening agent that provides high image silver density in a silver salt diffusion transfer method and also improves the whiteness of the white background area. be.

[0009]

[Means for Solving the Problems] The purpose of the present invention is to
In a method for producing an image-receiving material, the coating solution for forming an image-receiving layer and/or an adjacent layer containing at least gelatin, physical development nuclei, and an oil-soluble fluorescent brightener emulsion dispersion is coated on a rough surface support, and dried. The emulsified dispersion of an oil-soluble optical brightener is an emulsified dispersion of an oil-soluble optical brightener that has an amount of 4.0 times or less of the saturated dissolution amount of the high boiling point oil at 50°C, and the gelatin concentration of the coating layer is This was achieved by increasing the surface wet bulb temperature to 23° C. or higher and drying until it reached about 30% by weight.

[0010] Oil-soluble optical brighteners used in the present invention include, for example, substituted stilbenes and substituted coumarins described in British Patent No. 786,234, and US Pat.
Substituted thiophenes described in No. 5,762 are useful;
Optical brighteners such as those disclosed in No. 732 can be used with particular advantage. Typically useful optical brighteners will have one of the structural formulas below.

[0011]

[Chemical formula 1]

0012

[Case 2]

[0013]

[Chemical formula 3]

[0014]

[C4]

Here, Y1 and Y2 are alkyl groups, Z
1 and Z2 are hydrogen or an alkyl group, n is 1 or 2
, R1, R2, R3, R4, R5 and R6 are aryl, alkyl, alkoxy, aryloxy, hydroxyl, amino, cyano, carboxyl, amide, ester, alkylcarbonyl, alkylsulfo, or dialkylsulfonyl groups or hydrogen atoms. R7 and R
8 is a hydrogen atom, an alkyl group such as a methyl group or an ethyl group, or a cyano group. R9 is a phenyl group, a halogen atom, or an alkyl-substituted phenyl group. R10 is an amino group or an organic primary or secondary amine.

Next, specific examples of the water-insoluble optical brightener used in the present invention will be given.

[0017]

[C5]

[0018]

[C6]

[0019]

[C7]

[0020]

[Chemical formula 8]

[0021]

[Chemical formula 9]

[0022]

[Chemical formula 10]

[0023]

[Chemical formula 11]

[0024]

[Chemical formula 12]

[0025]

[Chemical formula 13]

[0026]

[Chemical formula 14]

[0027]

[Chemical formula 15]

[0028]

[Chemical formula 16]

[0029]

[Chemical formula 17]

[0030]

[Chemical formula 18]

[0031]

[Chemical formula 19]

[0032]

[C20]

[0033]

[C21]

[0034]

[C22]

[0035]

[C23]

[0036]

[C24]

[0037]

[C25]

[0038]

[C26]

[0039]

[Chemical formula 27] A method for preparing an emulsion of these water-insoluble optical brighteners is to dissolve the optical brightener in a high-boiling organic solvent as exemplified in British Patent No. 1,072,915, and add gelatin to the emulsion. There is a method of emulsifying and dispersing it together with a surfactant in a hydrophilic colloid such as. As a high boiling point organic solvent, U.S. Patent Nos. 2 and 32
2,027, 3,676, 137, 3,779
, No. 765, West German Patent No. 1, 152, 610, British Patent No. 1, 272, 561, JP 53-1520, JP 55-25057, JP 45-37376, etc. Although phthalate esters and phosphate esters such as
The amide compounds disclosed in No. 3, benzoic acid esters, and substituted paraffins can also be advantageously used.

If the amount of fluorescent whitening agent used is too small, the whiteness improvement effect will not be sufficient, and if it is too large, a bluish tinge will be added to areas with high image density, resulting in so-called blooming (
(eggplant color), resulting in a decrease in apparent image density. The luminous efficiency of fluorescence cannot be expressed uniformly because it varies depending on the type of fluorescent whitening agent, the type and concentration of oil used for emulsification, the coexistence of various quenching substances, the coexistence of other ultraviolet absorbing substances, etc. The amount of optical brightener used is 3 mg ~
Most preferably, it is used in a range of 300 mg/m2.

[0041] As a result of careful study on the ratio of high boiling point oil to fluorescent whitening agent, the amount of fluorescent brightening agent should be 2.5 times or less than the saturated amount dissolved in the high boiling point oil used at 50°C. good. If it is less than the saturated dissolution amount at 50° C. or more than 4.0 times, there will be disadvantages such as poor running properties, a decrease in transfer density, and a decrease in fine line reproducibility.

Examples of the high boiling point oil according to the present invention include US Pat. No. 2,322,027, US Pat. No. 3,676,137, US Pat.
No. 0, British Patent No. 1, 272, 561, Japanese Unexamined Patent Publication No. 53-1
No. 520, Japanese Patent Publication No. 55-25057, Special Publication No. 45-3
Phthalate esters and phosphate esters such as those described in U.S. Pat.
, 923, benzoic acid esters, substituted paraffins, and the like can also be advantageously used. Preferably, gelatin accounts for about 1/2 or more, more preferably about 2/3 or more of the total amount of binder in the image-receiving layer. The coating solution for forming the image-receiving layer or adjacent layer is generally preferably an aqueous solution containing a binder concentration in the range of about 2 to about 10% by weight.

The image-receiving layer is coated in the production of the image-receiving material of the present invention by a commonly used coating method (eg, air knife method, extrusion method, curtain method, etc.). The amount applied can vary as desired, but generally between about 1 and
It is preferable to apply it in an amount of about 5 g. The applied image-receiving layer is first cooled and then dried with hot air while gradually increasing the temperature, and drying is completed when substantially no water evaporates. Today, the time from application to complete drying is less than 10 minutes or less than 5 minutes. However, even with such short drying times, it has been avoided as much as possible to increase the drying temperature for the amount of gelatin coated because a uniform coating film cannot be obtained. In fact, the drying temperature of an image-receiving layer coated on a smooth support, such as a polyethylene resin coating film that has not been roughened, is increased during the drying process so that the surface wet bulb temperature is 23°C or higher. If this is increased, the maximum reflection density of the silver image is obviously lower than that of an image-receiving material that is completely dried while its surface wet bulb temperature remains below 23°C. Despite this,
No. 0-63535 discloses that the gelatin concentration in the image-receiving layer is gradually reduced during the drying process so that the surface wet bulb temperature of the image-receiving layer coated on a rough surface support is 23°C or higher. Although it has been stated that the maximum density of the silver image is higher if the drying is completed by the time when the emulsified dispersion of an oil-soluble optical brightener is This is not necessarily the case when the image-receiving layer forming liquid and/or the adjacent layer forming liquid contained therein are applied and dried.

[0044] In addition to the results of intensive studies, the present inventors found that when the amount of oil-soluble fluorescent brightener is 4.0 times or less than the saturated dissolution amount of high boiling point oil at 50°C, the reflection density increases, but other In this case, we found that the reflection density actually decreased.

Physical development nuclei used in the image-receiving layer of the image-receiving material according to the present invention include noble metals such as silver, gold, platinum, palladium, copper, cadmium, lead, cobalt, and nickel, their sulfides, selenium compounds, etc. It can be used.

In addition to gelatin, binders for the image-receiving layer include phthalated gelatin, acylated gelatin, phenylcarbamylated gelatin, carboxymethyl cellulose, hydroxyethyl cellulose, sodium alginate, polyvinyl alcohol, partially saponified polyvinyl alcohol, and polyvinyl alcohol. and maleic anhydride copolymer (
For example, heat processed products with styrene-maleic anhydride, ethylene maleic anhydride, etc.), polyacrylamide, poly-N-vinylpyrrolidone, latexes (for example, polyacrylic ester, polymethacrylic ester, polystyrene, polybutadiene, etc.) (single or copolymer of)
These water-soluble polymer compounds can be used alone or in combination.

The image-receiving layer can be hardened with a suitable hardening agent, and specific examples of the hardening agent include formaldehyde, formaldehyde,
Aldehyde compounds such as glutaraldehyde, ketone compounds such as diacetylcyclopentanedione, bis(2-chloroethylurea), 2-hydroxy-4,6-
Dichloro-1,3,5 triazine, U.S. Pat. No. 3,28
8,775, divinyl sulfone, U.S. Pat. No. 3,635,718.
compounds with reactive olefins as described in US Pat. No. 2,732,316, isocyanates as described in US Pat. No. 3,103,437, US Pat. No. 3,017 , No. 280, No. 2,
aziridine compounds as described in US Pat. No. 983,611, carbodiimide compounds as described in US Pat. No. 3,100,704, epoxy compounds as described in US Pat. No. 3,091,537, and halogenocarboxaldehydes such as mucochloric acid. , dioxane derivatives such as dihydroxydioxane, inorganic hardeners such as chromium alum, potassium alum, and zirconium sulfate, and these may be used alone or in combination of two or more.

The image-receiving layer contains a surfactant (for example, a natural surfactant such as saponin, a nonionic surfactant such as an alkylene oxide type, a glycerin type, or a glycidol type, higher alkylamines, quaternary ammonium salts, pyridine, etc.). Heterocycles, cationic surfactants such as sulfoniums, anionic surfactants containing acidic groups such as carboxylic acids, sulfonic acids, phosphoric acids, sulfate ester groups, phosphoric ester groups, amino acids, aminosulfonic acids, amino alcohols, etc. amphoteric surfactants such as sulfuric acid or phosphoric acid esters, fluorine-based anions, amphoteric surfactants, etc.), matting agents, discoloration inhibitors, color toning agents (typical examples include 1-phenyl-5-mercaptotetrazole, and other focal agents) Color toning agent described in Photographic Silver Halide Diffusion Process, page 61, published by Press)
, developing agents (e.g., hydroquinone and its derivatives, 1-phenyl-3-pyrazolidone and its derivatives, etc.), silver halide solvents (e.g., sodium thiosulfate,
ammonium thiosulfate, sodium thiocyanate, potassium thiocyanate, etc.). The layers adjacent to the image-receiving layer according to the present invention include, for example, an over layer, a neutralization layer, a timing layer, and a subbing layer.

The silver halide emulsion used in the photosensitive layer of the photosensitive material for silver complex diffusion transfer according to the present invention is preferably an emulsion containing mainly silver chloride, but is not limited to this. Commonly used emulsions, such as silver bromide and silver iodide, are sufficient as long as their silver complex salts have the ability to develop and diffuse in exposed and unexposed areas, respectively, at the speeds required for diffusion transfer. , silver chloride, silver chlorobromide, silver iodobromide,
Mention may be made of silver chloroiodide, silver chloroiodobromide and mixtures thereof.

Silver halide emulsions can be sensitized in a variety of ways when they are manufactured or coated. It may be chemically sensitized by methods well known in the art, such as with sodium thiosulfate, alkylthioureas, or with gold compounds such as rhodan gold, gold chloride, or a combination of both. In addition, commonly used spectral sensitization can be performed.

As the binder for the photosensitive layer, a polymeric substance commonly used in the production of silver halide emulsions, such as the binder described for the image-receiving layer, can be used. Further, the photosensitive layer can be hardened using a suitable hardening agent as described for the image-receiving layer. Furthermore, the photosensitive layer contains additives generally used in silver halide photosensitive materials, such as surfactants, antifoggants, matting agents, fluorescent dyes, and developing agents (e.g., hydroquinone and its derivatives, 1-phenyl-3- pyrazolidone and its derivatives). Furthermore, in addition to the photosensitive layer, auxiliary layers such as an undercoat layer, intermediate layer, protective layer, and release layer may be provided as necessary.

[0052] The support used in the present invention may be any material such as a polyolefin resin film such as polyethylene or polypropylene, or paper coated with the same, and preferably has a roughened surface. Examples of the surface roughening method include a solvent processing method, a foaming method, and a pressure molding method using a rough surface body, and any method for roughening the surface may be used. The surface roughness is preferably about 2 to about 20 μm in depth, which is the distance from the depression to the top of the surface unevenness, and about 5 to about 100 μm in size, which is the distance from peak to peak. Since the roughened resin surface is hydrophobic as it is, it is generally subjected to some kind of hydrophilic treatment such as corona discharge treatment or subbing treatment.

The processing solution for silver complex diffusion transfer in the present invention can have the composition of a conventional silver complex diffusion transfer processing solution. That is, developing agents for developing exposed silver halide, such as hydroquinone and its derivatives, 1-phenyl-3-pyrazolidone and its derivatives, solvents for undeveloped silver halide, such as sodium thiosulfate, ammonium thiosulfate, etc. , sodium thiocyanate, potassium thiocyanate, etc., sodium sulfite as a preservative, potassium bromide as a development inhibitor, additives such as 1-phenyl-5-mercaptotetrazole as a color toning agent, alkaline substances such as sodium hydroxide, Potassium hydroxide, lithium hydroxide, trisodium phosphate, thickening agents such as carboxymethyl cellulose, hydroxyethyl cellulose, etc. may be included.

[0054]

EXAMPLES The present invention will be explained in more detail below using examples.

Example 1

<Preparation of optical brightener emulsion>

[0057]
As an oil-soluble optical brightener, the compound shown in Chemical Formula 5 was mixed with n-dioctyl phthalate and ethyl acetate 2 as a cosolvent.
00 ml was mixed with 600 ml of a 6% gelatin aqueous solution containing 1.5 g of sodium di(2-ethylhexyl)succinate in solid content at about 60 degrees, and stirred vigorously using a homogenizer to prepare an emulsified dispersion. . n at 50℃
The solubility in 100g of -dioctyl phthalate is 2.
It was 5g.

<Preparation of image receiving material>

Physical development nuclei consisting of nickel sulfide and silver sulfide were prepared in a 1% gelatin aqueous solution by reacting equimolar amounts of nickel nitrate, silver nitrate, and sodium sulfide. On one side of a 110 g/m2 paper support coated with polyethylene on both sides, a gelatin image-receiving layer containing the above oil-soluble optical brightener-containing emulsified dispersion and the above core, toning agent, surfactant, and hardening agent was coated. A liquid was prepared.

[0060] The coating amount is 2 g/m dry weight of hydrophilic colloid.
I set it to be 2.

For drying, set it to cool for 10 seconds after application, then pass through a drying zone where the temperature gradually rises, and when about 80% of the water has evaporated, the surface wet bulb temperature is set to 40°C at the maximum dry bulb temperature as shown in Table 1. Drying was completed by changing the temperature to 18°C, 21°C, 23°C, and 25°C.

[0062] The oil-soluble optical brightener emulsified dispersion was 1.9 g/
They were each added to the solution before coating in an amount of m2 and coated. The added layers are shown in Table 1.

Sample No. Image receiving material No. 3 was prepared as follows.

A physical development nucleus consisting of nickel sulfide and silver sulfide was prepared in a 1% aqueous gelatin solution in the same manner as above, and the same amount of 1-phenyl-5-mercaptotetrazole was added as above, and it was applied to one side of the same paper support as above. These gelatins were coated at a concentration of 2.1 g/m2.

<Preparation of photosensitive material>

The light-sensitive material is a polyethylene laminated paper with an undercoat layer containing carbon black as an antihalation layer, and an ortho-sensitized silver chlorobromide (silver bromide 5 A gelatin silver halide emulsion layer containing 1.5 g/m2 of gelatin (mol%) converted to silver nitrate was provided.

The silver halide emulsion layer is impregnated with a hardening agent and hardened so as not to interfere with the diffusion transfer process.

<Processing liquid>

A diffusion transfer treatment solution having the following composition was used. water

800ml sodium hydroxide

25ml anhydrous sodium sulfite
100ml
hydroquinone

20g 1-phenyl-3-pyrazolidone

1g potassium bromide

3g sodium thiosulfate

30g 1-phenyl-5
-Mercaptotetrazole
Add 0.1g water to make 1000ml.

The photosensitive material produced as described above is imagewise exposed to light, the emulsion surface of the photosensitive material and the image receiving surface of the image receiving material are overlapped, and a processor having a diaphragm roller containing a processing liquid for diffusion transfer shown below is used. Both materials were pulled off 30 seconds after passing through the squeeze roller. The image receiving material is 30
After washing with water for a second and drying, the reflection density of the black part was adjusted to Macbeth Co., Ltd. RD5.
19 reflection densitometer. In addition, the whiteness was visually confirmed.

Table 1 shows the preparation conditions for the oil-soluble optical brightener emulsion dispersion and the drying conditions for the coating solution for each sample. At the same time, Table 1 shows the maximum reflection density of the black part of the image-receiving material after processing.

[0072]

[Table 1]

Samples 4, 5, and 6 having the structure of the present invention are Comparative Examples 1, 2, 3, 7, 8, 9, 10, 11, 12, and 13.
It can be seen that the reflection density at the highest part is higher than that of samples 1 and 14.

[0074]

[Effects of the Invention] By using the present invention, it is possible to provide a method for using an oil-soluble optical brightener and a drying condition for a coating solution that increase the reflection density of the silver part of an image and improve the whiteness of the white background part. did it.

Claims (1)

[Claims] Claim 1: At least gelatin on a rough support;
In a method for producing an image-receiving material in which a coating solution for forming an image-receiving layer and/or a coating solution for forming an adjacent layer containing physical development nuclei and an emulsified dispersion of an oil-soluble fluorescent brightener is applied and dried, the oil-soluble fluorescent brightener is The whitening agent emulsified dispersion is an emulsified dispersion of an oil-soluble optical brightener with a saturated dissolution amount of high boiling point oil at 50°C or more and 4.0 times or less, and the gelatin concentration of the coating layer is about 30% by weight at the latest. 1. A method for producing an image-receiving material, which comprises drying the image-receiving material by raising its surface wet bulb temperature to 23° C. or higher until the temperature reaches 23° C.