JPH0467177B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Technical Field of the Invention The present invention relates to a non-silver salt image forming material of the type that provides a visible image due to a physical phenomenon after exposure, and more particularly to a non-silver salt image forming material that provides a positive image due to a physical phenomenon after exposure. Relating to imaging materials.

Technical background of the invention and its problems In recent years, non-silver salt image forming materials have been reconsidered due to the limited nature of silver resources, and printed circuit boards have been put into practical use as image forming methods that utilize physical development. There are only methods for forming conductive patterns.

For example, an activated photoconductor compound such as TiO ₂ ZnO is applied to the surface of the substrate, exposed to UV light in a pattern, and then brought into contact with a metal salt solution such as PdCl ₂ , after which the metal is reduced only in the exposed areas using physical phenomena. A method for forming conductive patterns by depositing Ag, Pd
There is a method of coating a substrate with a metal halide or organic acid salt by an appropriate method, and exposing it to UV light or the like to precipitate metal particles of Ag or Pd only in the exposed areas to form an image. however,
These methods use a negative-type image forming material in which a metal image is formed in the exposed area. Therefore, when manufacturing a printed circuit board with through-hole plating using an additive method, the exposure inside the through-hole area is However, there is a problem in the reliability of exposure within this through hole. On the other hand, as a positive type image forming material that forms an image on unexposed areas, salts of metal ions (Sn ²⁺ , Ti ⁵⁺ , etc.) whose oxidation state changes by UV irradiation with a short wavelength of 300 nm or less are placed on a substrate. A method has also been reported in which metal is deposited in a pattern only on unexposed areas by coating and pattern exposure, but this method has drawbacks such as poor photosensitivity and resolution.

Further, as a positive image forming material, there is an image forming material using a diazonium salt which has been put into practical use for a long time. This material is used for blueprint copying and color proofing because of its high resolution, the ability to produce a variety of colors using couplers, and its ease of operation. However, since it is a dye image, it has the disadvantage that it is difficult to obtain high density.

Purpose and Summary of the Invention The present invention provides high density,
It is an object of the present invention to provide an image forming material which makes it possible to obtain a positive image with high resolution and comparable to an image obtained by silver salt photography.

The image forming material according to the present invention has an image forming layer on a support comprising 1 to 10 parts by weight of a metal compound which is reduced to become metal development nuclei, 0.001 to 50 parts by weight of dichromate, and 100 parts by weight of gelatin. It is characterized by the fact that it has been provided.

When obtaining an image using the image-forming material according to the present invention, the image-forming layer is pattern-exposed to deactivate the physical phenomenon effect in the exposed area, and the image-forming layer is treated with a reducing liquid and a physical phenomenon liquid. Then, metal particles are grown in the unexposed areas to form an image. Therefore, the image obtained using the image forming material according to the present invention is a positive image.

DETAILED DESCRIPTION OF THE INVENTION The present invention will be described in more detail below with reference to the drawings. In the following description, “part” and “%” are
Unless otherwise specified, measurements are based on weight.

FIG. 1 is a sectional view in the thickness direction conceptually showing one embodiment of the image forming material of the present invention.

Image forming material A of the present invention as shown in FIG.
is formed by providing an image forming layer 2 on a support 1.

As the support 1, any solid material such as glass, wood, paper, plastic film, woven fabric, non-woven fabric, etc. can be used. These supports 1 may be subjected to pretreatment to improve adhesion, such as corona discharge treatment and primer treatment, if necessary. The image forming layer 2 includes a gelatin layer in which a metal compound and dichromate, which are reduced and become metal phenomenon nuclei, are dispersed.
Alternatively, it is formed by coating the support 1 with a dissolved image forming composition.

Metal compounds that are reduced to give metal development nuclei include water-soluble salts such as chlorides and nitrates of metals such as palladium, gold, silver, platinum, and copper; for example, palladium chloride contained in the activator solution for electroless plating. Water-soluble salts such as silver nitrate, gold tetrachloride, etc. are used. Among them, palladium, gold, platinum,
Water-soluble salts of copper, especially water-soluble salts of palladium, are preferably used. This metal compound is a gelatin
It is desirable to include it in an amount of preferably (1) to (10) parts per 100 parts.

The image forming layer 2 preferably contains water-soluble metal compounds as described above (a commercially available activator liquid for electroless plating can be used as is),
A dichromate is mixed with an aqueous gelatin solution to form a liquid with a viscosity of about 10 to 1000 centivoise suitable for coating, and this is coated onto the support 1 and dried to obtain a coating film with a thickness of usually 0.05 to 30μ. It will be done. As the dichromate, ammonium dichromate, potassium dichromate, etc. are used, and the amount is 0.001 to 50 parts, preferably 0.01 parts to 100 parts of gelatin.
Preferably, it is included in an amount of ~10 parts.

The image forming layer is preferably subjected to hardening treatment in order to suppress elution of the binder into the developing solution during physical development, which will be described later. Hardening treatment uses Al compounds such as potash alum, Cr compounds such as chromium sulfate,
An aqueous solution of other hardening agents such as aldehydes, diketones, maleic acid copolymers, etc. may be coated on the image forming layer, or the above hardening agent may be mixed with 100 parts of gelatin in the image forming composition in advance. This is carried out by mixing the agent in an amount of, for example, 0.1 to 50 parts.

In the present invention, although the reaction mechanism during image formation is not necessarily clear, there is almost no difference in the permeability of the processing liquid to the exposed and unexposed areas of the image forming layer. It is assumed that the plating suppressing effect is not due to the hardness of the image forming layer, but rather that metal particles such as PdCl ₂ , which are plating nuclei, lose their ability as development nuclei due to a photoreaction in the image forming layer due to exposure. be done.

An image can be formed from the obtained image forming material in the following manner.

In the first method, as shown in FIG. 2, the image forming layer is exposed in a pattern through a mask 3, and then the image forming layer is brought into contact with a reducing agent to remove the metal in the exposed areas 2A of the image forming layer. The first step is to deactivate the development nuclei.
The image forming layer is brought into contact with a physical developer containing reducible metal ions and a reducing agent, and the metal development nuclei are precipitated and grown in the non-exposed area 2B by reduction of the reducible metal ions. This is a method of implementing a second development step of forming an image made of metal particles. The first development step and the second development step can also be carried out simultaneously by using a relatively strong reducing agent in the physical developer used.

In the second method, a reducing agent is brought into contact with the image forming layer to form metal development nuclei in the image forming layer, followed by pattern exposure, and a developing solution containing reducible metal ions and a reducing agent. exposure section 2
In this method, the metal development nuclei of A are deactivated and an image is formed in the non-exposed area 2B by metal particles deposited and grown by reduction of the reducible metal ions.

The positive image according to the present invention obtained by the above method has a transmission density of 4 or more, high resolution,
An image that can be substituted for an image obtained by silver halide photography can be obtained. In addition, since the obtained positive image is a metal image, it can be corrected using a reducing fluid such as Farmer reducing fluid or Kodak R-4, and it can also be used as a positive lithographic film, mask material, etc. be. Furthermore, when the physical development is performed using nickel plating, for example, the image area has conductivity, and it has the possibility of being applied to printed circuit boards.

The present invention will be explained in more detail with reference to Examples below.

Example 1 Gelatin (Nitta Gelatin #150 8% aqueous solution)
12.5 parts ammonium dichromate (5% aqueous solution) 5.0 parts N-N'-dimethylolurea (5% aqueous solution)
1.0 part PdCl _2- acid solution (10x Redshumer solution manufactured by Nippon Kanigen) 7.0x The above components were thoroughly mixed and dissolved, and the resulting composition for the image forming layer was subjected to plasma treatment in advance using Miyabur #30. It was coated on a polyester film (Lumirror T/100, manufactured by Toray Industries, Ltd., thickness: 100 μm).

Then, it was left to stand at room temperature for 1 hour, and further aged in an oven at 40°C for 3 hours.

The dry film thickness of the resulting image-forming layer coating was 3 μm. This image forming layer is coated with an ultra-high pressure mercury lamp (3kw, 1
pattern exposure was carried out for 30 seconds using a distance of m.

Next, it was immersed for 20 seconds in a reduction bath (Shiba Nikkel manufactured by Okuno Pharmaceutical) at 20°C, and then immersed for 60 seconds in a physical phenomenon liquid (TMP Chemical Nickel A/B = 1/1 manufactured by Okuno Pharmaceutical) at 20°C having the following composition. However, a positive image was obtained that reproduced 150-line 95-5% halftone dots without causing any fogging.

Physical developer (A/B=1/1) Solution A Copper sulfate Nickel sulfate Hydrazine sulfate 60g/l 15g/l 45g/l Solution B Sodium hydroxide Potassium tartrate Sodium carbonate 45g/l 180g/l 15g/l Examples 2 Gelatin (Nitta Gelatin #150) 8% aqueous solution
12.5 parts Potassium dichromate 5% aqueous solution 4.0 parts Cahadas (C-5S manufactured by Nippon Carlito) 5% aqueous solution 0.1 part PdCl _{dihydrochloric} acid solution (10 times solution of Red Shumer manufactured by Nippon Kanigen) 7.0 parts Substituted for ammonium dichromate in Example 1 An image forming material was prepared in the same manner as in Example 1 except that 4 parts of a 5% aqueous solution of potassium dichromate was used, and image formation was performed.
A positive image reproducing 5% halftone dots was obtained.

[Brief explanation of the drawing]

FIG. 1 is a schematic cross-sectional view in the thickness direction showing the laminated structure of the image forming material of the present invention, and FIGS. 2 and 3 show intermediate steps of the image forming method of the present invention using the image forming material shown in FIG. FIG. 1...Support, 2...Image forming layer (2A...Exposed area, 2B...Visible image), 3...Transparent original, A...
...Image forming material.

Claims (1)

[Claims] 1 Metal compound 1 that is reduced and becomes a metal development nucleus
An image forming material for obtaining a non-reflective positive image, characterized in that an image forming layer consisting of 10 parts by weight, 0.001 to 50 parts by weight of dichromate, and 100 parts by weight of gelatin is provided on a support. .