JPS60450A - Photographing method - Google Patents

Abstract

PURPOSE:To obtain a negative or positive image by using the same original and the same film for photoengraving by combining a transmission type film for photoengraving having a metallic image and a negative-positive (or positive-positive type) photosensitive film and specifying respectively an exposing method. CONSTITUTION:A metal vapor-deposited film 2 and a photosensitive resin layer 3 are provided to a polyester film 1 and a film 6 for a positive metallic image type photoengraving or a film 7 for a negative metallic image type photoengraving is obtd. from the same original by using a transparent negative original. For example, the film 6 is used to expose the transmitted light from a light source 8 on a negative-positive type photosensitive film 10 thereby obtaining a negative- positive image. A diffusion plate having 1/5-1/10 degree of diffusion is placed on the film 6 and the reflected light is irradiated to the film 10 in the case of exposing said photosensitive film by using light sources 8, 8' and irradiating the reflected light of 45 deg. angle relative with the respective optical axis thereto and obtaining a positive-positive image. The negative or positive image is thus obtd. by using the same original 6 and the same film 10.

Description

[Detailed description of the invention] The present invention relates to a photographing method, and in particular, it is possible to freely obtain a negative image or a positive image in a plate-making film by using the same original and the same plate-making film during photoengraving. The purpose is to provide photography methods.

Conventionally, lithium film with silver halide as a photosensitive nucleus has been used as a manuscript for making printing plates. Lith film usually turns black in the areas exposed to light, while there are various formats for producing original film for printing. When converting from a positive image to a positive image or from a negative image to a negative image, a positive-positive type is used.

In this case, it is necessary to use different films, which is complicated.

The present invention was made in view of these drawbacks, and uses the same original with a metal image and the same plate-making film,
By changing only the exposure method, it is possible to obtain a positive image from a negative original using transmitted light illumination, and a negative image using reflected light illumination.Conversely, it is possible to obtain a positive image from a negative original using transmitted light and a negative image using reflected light; It concerns a photographic method that made it possible to obtain negative images.

That is, in the present invention, when image information of a document placed on a document rack is photographed by a plate-making camera, a transparent metal image type plate-making film having a metal image is placed on the document rack, and a film mounting plate is placed on a film mounting plate. After setting each negative-positive type (or positive-positive type) photosensitive film, if you want to record image information that has a negative-positive (or positive-positive) relationship with the image in the original on the photosensitive film, the original is exposed to transmitted light. If you want to record image information on the photosensitive film in a positive-positive (or negative-positive) relationship with the image in the original by exposing the photosensitive film through a photographing lens, A diffuser plate with a diffusivity of 115 to 1/10 is placed on top of the film, and then reflected light is irradiated to image-expose the photosensitive film through a photographic lens to impart desired image information to the photosensitive film. It consists in a photographing method characterized by recording.

The present invention will be described in detail below with reference to the drawings.

FIG. 1 shows an example of the structure of a metal-based image plate making film. This film consists of a transparent polyester film (1) with a thickness of 100 μm, a metal vapor deposition layer (2) with a thickness of 1000 μm and few pinholes, and a layer of metal vapor deposited with a thickness of 2 μm to
This is a metal image plate making film (4) provided with a 5μ transparent photosensitive resin layer (3).

The metal image plate making film (4) having such a structure is exposed in close contact with a transparent negative original (5) as shown in FIG. Here, the transparent original (5) has a halftone image output from a color separation scanner, or has a character image obtained by photographing phototypesetting characters printed on photographic paper, or It has a line image obtained by photographing a mount, and is not particularly limited.

Next, the image-exposed metal image plate making film (4) is developed, but if the photosensitive resin constituting the photosensitive resin layer (3) is a photocurable type, after development, the image will be as shown in Figure 3. In the case of a photodegradable type, the parts exposed to light become resist and potash, and after development, the areas not exposed to light become resist, as shown in Figure 4.

Next, the resist is removed by development and the exposed portion of the metal vapor deposited layer is etched to remove the metal vapor deposited layer. 5 and 6 each show the state of the metal image plate making film after the etching process, and FIG. 5 shows the state of the metal image plate making film. When this plate-making processed metal image type plate-making film (6) is viewed with reflected light, the metal vapor deposited layer (
A positive image is visible due to the reflection of 2), and when viewed under transmitted light, the metal vapor deposited layer (2) is a light-shielding layer, and a high contrast negative image with a transmission density of 4.0 or more is visible. In addition, plate-making processed metal image type plate-making film (when the power is viewed with reflected light or transmitted light, the negative and positive are reversed from the case of overwriting.

Next, place the metal image-type plate-making film (6) on which the metal image has been formed in this way on the document rack of the plate-making camera, and place the negative-positive type photosensitive film on the film mounting plate. , take a photo.Metal image plate making film (
6) Or (If you want to record image information that has a negative/positive relationship with the metal image in the photosensitive film, use a processed metal image platemaking film (6) in the same way as for normal photography as shown in Figure 7. Or (place the light source (8) after the force and use the photographic lens (
Photographing is performed on a negative-positive type photosensitive film (10) via a film (9). In this way, image information having a negative/positive relationship with the image in the document is well recorded on the photosensitive film a0. The only transparent part of the processed metal image plate making film that serves as the manuscript is a polyester film, and compared to the commonly used silver salt lithium film, since there is no gelatin layer, the transparency is better and the exposure time is about 20% shorter. Yo().

On the other hand, when recording image information in the opposite relationship to that described above on a photosensitive film, two light sources (
8) and (8)' are used to shoot with light from two directions. However, when taking pictures using a camera for plate making, the illumination will be from an angle between 30 degrees and 60 degrees with respect to the optical axis passing through the center of the photographic lens (9), as shown in Figure S. However, since the metal image plate-making film (6) or the metal image is specularly reflected, it is reflected at an angle symmetrical to the illumination angle, and the light that enters the photographic lens (9) cannot be obtained. No image can be obtained on positive-negative silver salt film.

Therefore, the inventors of the present invention conducted extensive studies and solved the problems described above as follows.

First, a measuring device for measuring the degree of diffusivity, the configuration of which is shown schematically in FIG. 9, was assembled. This device has a photomultiplier (121) located at the position where the laser light emitted from the helium neon laser (11) reaches after specular reflection, and a photomultiplier (13) located at a 45 degree angle with respect to the incident laser light. In addition, a diffusion plate and a metal image plate making film (15) are arranged.

Next, 04 diffusion plates with different degrees of diffusion were placed in this device.
The degree of diffusion was determined by the light amount ratio (2) between Photomul (12) and Photomul Q31. In this way, a diffuser plate with different diffusivity is attached to the surface of the metal image plate making film (6) or (light source (8), (8) shown in Fig. 8).
)' was fixed at a 45 degree position, a positive negative type silver halide film α0) was placed at the (10)v') position, and photography was repeated.

Under these conditions, photographing using reflected light was possible with a degree of diffusion of 1 to τ. However, as a result of this, the fine parts of the metal image cannot be reproduced and the resolution of the image does not improve, and at the same time, the diffusion of the non-image area becomes large. The contrast with the image area has disappeared and the exposure conditions have become narrower.

Also, when the value is -0 or less, it takes too long to take a picture. It has been found that a diffusivity higher than this is appropriate and image information can be recorded satisfactorily.

Although the present invention has been described above using an example in which a negative-positive type photosensitive film is used as the photosensitive film, the present invention is not limited thereto, and a positive-type photosensitive film can also be used.

When a positive-type photosensitive film is used, the type of image information (negative or positive) obtained in the photosensitive film is, of course, opposite to that obtained when a negative-positive type photosensitive film is used. .

(Example) A photosensitive material having the following composition was applied to a thickness of 3 μm using a bar coater on Metal Me 100 manufactured by Toshi Co., Ltd. (a 600× aluminum vapor-deposited layer was formed on a 100 μm polyester film).

After drying 21.8 parts of methyl cellosolve, an aqueous solution of Gohsenol GL-0.5 manufactured by Nippon Gosei Kagaku Co., Ltd. was applied to a thickness of 2 μm using a bar coater and dried to obtain a film for metal image plate making.

Next, this metal image plate making film was brought into close contact with a positive original containing halftone dot images and character images, and exposed for 50 seconds using a 5 kW ultra-high pressure mercury lamp printer manufactured by Oak Seisakusho. The resist was developed and the aluminum deposited layer was etched by rubbing with a sponge for 1 minute and 30 seconds in a post-exposure developer to obtain a negative image.

The thus obtained treated metal image plate making film (I5) was applied to a plate making camera C-5 manufactured by Dainippon Screen Co., Ltd.
I placed it on the No. 9 manuscript shelf.

Place black paper (light-shielding paper, 16) on the text part of the metal image plate making film (15), and use Kodak Lith Film Type 3 as the photosensitive film (photographing film).
After exposing the lithographic film to transmitted light for 5 seconds, prescribed development and fixing treatments were performed to obtain a positive halftone dot image.

Next, apply the metal metal sheet from the back to the area other than the text area, and apply a diffuser plate (Nomaru Neoart (thickness 80μ) to the surface).
) (19), exposure was applied for 20 seconds from two directions at an angle of 45 degrees to the optical axis as reflected light illumination, and a negative character image was obtained by predetermined development and fixing processing.

FIGS. 6 and 4 are explanatory diagrams of a film for metal image plate making that has been subjected to development processing. FIGS. Figure 7 is an explanatory diagram of the photographing method of the present invention using transmitted light, Figure 8 is an explanatory diagram of the photographing method of the present invention using reflected light, and Figure 9 is an illustration of an apparatus for measuring the degree of diffusion of a diffuser plate. FIG. 10 is an explanatory diagram showing the arrangement of the equipment, and FIG. 10 is an explanatory diagram showing the relationship between the metal image plate-making film having a metal image, the light-shielding paper, and the diffusion plate.

Claims (1)

[Claims] (1) When photographing image information of a document placed on a document rack using a plate-making camera, a transparent metal image plate-making film with a metal image is placed on the document rack, and a negative/positive plate ( After setting each photosensitive film (or positive/positive type), if you want to record image information in a negative/positive (or positive/positive) relationship with the image in the original on the photosensitive film, irradiate the original with transmitted light. , image exposure is performed on the photosensitive film through a photographing lens, and when it is desired to record image information in a positive-positive (or negative-positive) relationship with the image in the document on the photosensitive film, it is possible to perform image exposure on the photosensitive film by diffusing it onto the document. After placing a diffuser plate with a power of 115 to 1/10, reflected light is irradiated, image exposure is performed on the photosensitive film through a photographing lens, and desired image information is recorded on the photosensitive film. A shooting method featuring