JPS589758B2 - recording material - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a new heat-sensitive recording material and a method for producing the same, and in particular to a heat-sensitive recording material in which a water-soluble high molecular weight protein compound is contained in a heat-recording layer and film-forming properties are improved. and its manufacturing method.

In the field of thermosensitive recording, the recording layer is selectively thermally changed by applying a thermal pattern to form a latent image, and either the thermally changed portion or the unchanged portion of the recording layer is removed to form a relief recorded image. A number of thermal recording materials have been proposed that obtain the following.

JP-A-52-82431 and JP-A-52-1233
No. 1 proposes a new thermal recording material using the low molecular weight protein albumin.

According to this proposal, xenon is applied to a heat-sensitive recording material obtained by mixing albumin dissolved in water and a photothermal conversion substance dispersed or dissolved in water, coating the mixture on a suitable support and drying it, through a heat-cutting mask. 1 using a light source such as a flash
When exposure is carried out with an exposure time of 0-2 seconds or less, the contained photothermal conversion substance generates heat, making the recording layer thermally insoluble, and the unaltered portion can be easily removed with running water, resulting in an extremely high quality relief recorded image. .

However, albumin, which has a relatively low molecular weight and is easily soluble in water, has poor film-forming properties, and therefore a layer can only be formed by adding glycerin which has a plasticizing effect.

Since the addition of glycerin has a large effect on the drying properties of the layer, winding suitability, etc., the amount added is limited.

Unlike the above-mentioned albumin, high molecular weight proteins such as globulin, prolamin and glutelin are hydrophilic due to their high molecular weight, but are insoluble in water, so they have not been considered a problem as recording materials until now.

However, these water-insoluble protein compounds can be treated with dilute aqueous solutions of acids, alkalis, or neutral salts, or with denaturing agents.
It is known that it can be dissolved in water by coexisting with urea, known as urea, and its derivatives.

Furthermore, the inventors have discovered that water-soluble organic compounds having -NH2 groups or >NH groups can be used for the same purpose.

Specific examples of water-soluble compounds having -NH2 groups or >NH groups include guanidine salt compounds such as guanidine hydrochloride and guanidine phosphate, hydrazine salt compounds such as hydrazine hydrochloride and hydrazine sulfate, and 2,4-diamino-6-methyl - triazine derivatives such as 5-triazine, triazole derivatives such as benzotriazole, 3-amino-1,2,4-triazole, water-soluble linear nitrogen-containing organic compounds such as acetoamide, thioacetamide or caprolactam; Examples include cyclic nitrogen-containing organic compounds.

The aqueous solution of the high molecular weight protein compound thus solubilized in water is coated on a suitable support such as polyethylene, terephthalate, or film and dried to obtain a thermal recording material.

The present inventors have completed this invention by discovering that the recording layer of the obtained recording material has good film formability and can form a coating film with high strength because of the high molecular weight protein compound.

The object of the present invention is to provide a thermal recording material that makes a water-insoluble high molecular weight protein compound soluble in water and forms a coating film with good film forming properties and high strength based on the high molecular weight. To provide a manufacturing method.

The present invention is characterized in that a thermal recording layer containing one or more water-soluble high molecular weight protein compounds selected from globulin, prolamin, and glutelin is provided on a support. Provide recording materials for

The present invention also provides a support in which one or more high molecular weight protein compounds selected from globilin, prolamin, and glutelin are made soluble in water with a dilute aqueous solution of acid, alkali, or neutral salts and are contained in the thermal recording layer. A method for producing a recording material is provided.

Further, the present invention is characterized in that one or more high molecular weight protein compounds selected from glopurins, prolamins, and glutelins are rendered soluble in water using a denaturing agent and contained in the thermal recording layer, which is then provided on the support. A method for producing a recording material is provided.

High molecular weight protein compounds that can be used in the thermal recording material of this invention include isolated simple proteins such as globulin prolamin and glutelin, as well as globulin produced on an industrial scale as a vegetable protein. Soybean protein, wheat protein mainly composed of prolamin and glutelin, corn protein (Zein) mainly composed of prolamin, etc. can also be used.

The recording material of the invention comprises a substance or substance mixture o5C in the recording layer which generates heat by absorbing electromagnetic radiation.
Either it exists or it does not exist (therefore it can be divided into two quibs).

That is, the first type of recording material consists of a support (which may be provided with an undercoat layer) and a recording layer, and this recording layer mainly consists of the protein compound described above.

There are two recording methods: one is to bring the thermal pattern into direct contact with the original and perform selective thermal insolubilization, and the other is to selectively (thermal insolubilize) by receiving the heat generated and accumulated during exposure in the heat ray absorption area of the document using a reflective exposure method. There are cases where this is done.

In order to reduce the lateral diffusion of heat in the recording material in order to improve the quality of the recorded image, it is necessary to keep the contact time and exposure time of the thermal pattern as short as possible.

In particular, it is preferable that the exposure time is no longer than 10-1 sec, and optimal results are obtained with exposure of 10-2 sec or less, for example 10-2 to 10-5 sec.

The second type of recording material consists of a support (optionally provided with a subbing layer) and a recording layer consisting of the protein compound and a substance that absorbs electromagnetic radiation and generates heat (photothermal converter). material) or a mixture of these substances.

This photothermal conversion material can be present in the recording layer in dissolved or also dispersed form.

Examples of the photothermal conversion substance include carbon black, graphite, fine powder of metals having an atomic weight of 45 to 210, fine powders of oxides or sulfides of these heavy metals, black or dark-colored dyes, or organic pigments.

The recording layer has an optical density of 2.0 or more in transmitted light and 1.0 in reflected light.
It is necessary in the graphic arts field that the value is 0 or more, and particularly preferably 3.0 or more for transmitted light and 1.5 or more for reflected light.

Therefore, it is preferable to contain the photothermal conversion substance in an amount that exhibits these values.

Recording methods include direct contact with a thermal pattern to selectively insolubilize the recording layer, and exposure through a mask to selectively apply electromagnetic radiation to insolubilize the recording layer with heat generated by a photothermal conversion substance. There is.

In order to reduce the lateral thermal diffusion in the recording material in order to improve the quality of the recorded image, the contact time or exposure time of the thermal pattern needs to be as short as possible.

In particular, the exposure time is 10-1 sec or less, and more preferably 10-1 sec or less.
Exposure for 2 to 10-5 seconds is preferred.

Next, examples will be shown.

Percentages are by weight unless otherwise noted.

Example 1 Soybean protein powder (Solpy 200, manufactured by Nisshin Oil Co., Ltd.) 10
g, 12 g of urea (1st grade reagent, manufactured by Wako Pure Chemical Industries, Ltd.) were added to 78 g of water, left overnight, and stirred well to form a uniform solution.

The above solution was applied to a 100 μm thick polyester film using a wire bar and dried with warm air at about 40° C. to obtain a recording film.

The above-mentioned recording film was as good as or better than the one using albumin.

The recording layer described above was brought into close contact with a reflective original having a black positive image, and exposed from the support side with the dial of a xenon flash printer (Resoze Sofax FX-150 manufactured by Riso Kagaku Kogyo Co., Ltd.) set to TX-0. The recording film was treated with running water at room temperature to obtain a positive and relief image.

Further, in order to visualize the image, the recording film was immersed in an alcohol solution containing 5% methylene blue, then washed with water and dried to obtain a clear blue image.

Example 2 10 g of wheat gluten (reagent, manufactured by Wako Pure Chemical Industries, Ltd.),
Add 15 g of thiourea (grade 1 reagent, manufactured by Wako Pure Chemical Industries, Ltd.) to 75 g of water, let stand overnight, and stir well to form a uniform solution.

The above solution was applied to a polyester film having a thickness of 100 μm using a wire bar and dried with warm air at about 40° C. to obtain a recording film.

Using the recording film described above, image recording was carried out in the same manner as in Example 1, and similar results were obtained.

Example 3 10 g of zein (reagent, manufactured by Wako Pure Chemical Industries, Ltd.) and 2 g of ε-caprolactam are added to 88 g of 70% hydrous alcohol and stirred thoroughly to form a uniform solution.

The above solution was applied to a polyester film having a thickness of 100 μm using a wire bar and dried with warm air at about 40° C. to obtain a recording film.

Using the recording film described above, image recording was performed in the same manner as in Example 1, and similar results were obtained.

Example 4 Add 10 g of soybean protein powder (Solpeace 00) to 9 og of water, add aqueous ammonia, adjust to pH 10, and leave overnight.

Next, stir well to obtain a homogeneous solution, and neutralize by adding 10% acetic acid aqueous solution to pH 7-8.

The above solution was applied to a 100 μm thick polyester film using a wire bar and dried with warm air at about 40° C. to obtain a recording film.

Using the recording film described above, image recording was carried out in the same manner as in Example 1, and similar results were obtained.

Example 5 10 g of carbon blank (No. 999 manufactured by Columbian Carbon), polyvinylpyrrolidone (average molecular weight 36)
0000), 10 g of a 10% solution by weight, and 1 g of polyethylene glycol (manufactured by Kanto Kagaku Co., Ltd., average molecular weight 6000).
, and 79 g of water were mixed and dispersed for 48 hours using a ball mill to prepare a dispersion containing 10% carbon black.

To 10 g of the protein compound aqueous solution prepared in the same manner as in Examples 1, 2, 3, and 4, 10 g of the carbon blank dispersion described above was added and stirred well to prepare a uniform coating solution.

Each of the above-mentioned coating liquids was applied onto a 100 μm thick polyester film using a wire bar and dried with warm air at about 40° C. to produce four types of recording films.

A transparent original having a negative image was brought into close contact with the recording layer of the above-mentioned recording film, image exposure was carried out with the dial of a xenon flash printer (Resources Sofax FX-150) set to TX-1, and the recording film was then treated with running water. A black positive image was obtained.

Example 6 Instead of carbon black in Example 5, iron black (reagent, black iron oxide Fe3O4 manufactured by Wako Pure Chemical Industries, Ltd.) or diamond black (C.I. manufactured by Daido Kasei Co., Ltd.) was used.
I. 50440), a recording film was prepared in the same manner, and similar results were obtained.

Example 7 Using a coating solution prepared in the same manner as in Example 5, a coating solution with a thickness of 13
A recording paper using 0 or 110μ white synthetic paper as a support was prepared, and the same method as in Example 5 was carried out using Resourxenofax EX-15.
0 and the dial was set to TX-O for image exposure, and then treated with running water at room temperature to obtain a clear black image.

Example 8 A 2% aqueous solution of gelatin (reagent, manufactured by Wako Pure Chemical Industries, Ltd.) was applied onto the black recording layer of four types of recording films obtained in the same manner as in Example 5 using wire bar No. 12 and dried with warm air at about 40° C. to form a protective layer.

Gakken Fax Model. Image recording was performed using GOM208M (a scanning recording device manufactured by Gakken Co., Ltd.) using a line drawing original by applying a voltage of 18 KHz and 100 V to a recording needle of 1200 μm diameter.

The recorded film was treated with running water at room temperature to obtain a black image corresponding to the original.

Comparative Example Ovalbumin (JIS, K8068, Kanto Chemical Co., Ltd.)
After adding 10g of the product to 30g of water and leaving it overnight, the temperature of the liquid was 2.
The mixture was stirred and dissolved at 0 to 30°C to prepare an approximately 25% albumin aqueous solution.

To 10 g of the above solution, 10 g of a carbon black dispersion obtained in the same manner as in Example 5 and 0.5 g of glycerin (reagent manufactured by Kanto Kagaku Co., Ltd.) were added and stirred thoroughly to prepare a uniform coating solution.

The above-mentioned coating solution was applied to a polyester film having a thickness of 100 μm using a wire bar, and dried with warm air at about 40° C. to obtain a recording film for comparison.

A bending test was conducted on the above-mentioned comparative recording film and the recording film obtained in Example 5, and the results showed that the recording layer of the comparative recording film cracked and peeled off when bent by about 90 degrees. In the recording film obtained in the above example, the recording layer did not crack or peel even when bent over 90 degrees.

Claims (1)

[Claims] 1. A thermal recording layer containing one or more water-soluble high molecular weight protein compounds selected from globuvin, prolamin, and glutelin is provided on a support. Recording material featuring. 2. One or more high molecular weight protein compounds selected from globulins, brolamins, and glutelins with acids,
1. A method for producing a recording material, which comprises making the material soluble in water with a dilute aqueous solution of an alkali or neutral salt, incorporating it into a thermal recording layer, and disposing it on a support. 3. A recording material characterized in that one or more high molecular weight protein compounds selected from globulin, brolamin and glutelin are made soluble in water with a denaturing agent, contained in a thermal recording layer, and provided on a support. Production method.