JP2539691Y2 - Flat net film - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flat tint film used in a flat tinting step in photolithography.

[0002]

2. Description of the Related Art In a photoengraving process, a flat halftone print of a line drawing or a character is performed by stacking a flat halftone film on a light-shielded mask plate except for a portion to be flattened. Usually, after fixing the flat netting film with an adhesive tape or the like, the flat netting film is inverted to a silver halide film to obtain a line drawing, a character, or the like, which is half-finished.

However, in the case where line drawings and characters are small and line drawings and characters etc. which are to be concealed are adjacent to each other, the flat film which is overlaid on the mask plate has a size of line drawings and characters. You have to prepare the cut piece and paste it with adhesive tape.

In this case, when the flat film is pasted with an adhesive tape, since the flat film is small as described above, the flat film is adhered to a corresponding position of a line drawing, a character or the like of the adjacent flat film. Since the tape is stuck or the amount of tape required for sticking the adhesive tape is small, there has been a problem that the sticking operation is extremely difficult.

When two or more colors are overprinted, plates corresponding to the respective colors are prepared. For example, when two colors of black and yellow are overprinted, each black plate and yellow plate are printed. In order to make it, it is necessary to carry out the work of flattening.

[0006] The flat net film to be stuck on these is
In order to prevent moiré, it is necessary to make the difference between the angles not less than 15 degrees.

[0007] Usually, a screen angle of 45 ° for a black plate and a screen angle of 30 ° for a yellow plate, or a screen angle of 45 ° for a black plate and 90 ° for a yellow plate is set, and a flat glue film is coated with an adhesive tape by a blanking operation. Paste in.

However, there is a problem in that the above-mentioned screen angle is difficult to obtain when a flat halftone film is pasted on a small portion as described above, and moire may be generated when overprinting.

An object of the present invention is to solve the above-mentioned conventional problems.

That is, it is easy to set an angle and to position when pasting on a mask plate or a negative plate. Further, no adhesive tape is required, and there is no trace of the adhesive tape on the silver halide film after reversing. Another object of the present invention is to provide a flat film which does not contain bubbles at the time of application by using an adhesive comprising small adhesive particles.

[0011]

According to the present invention, in order to solve the above problems, a removable adhesive is applied to one surface of a film substrate.

[0012]

[Function] When performing the work of concealing, the film is directly overlaid on a mask plate or a negative plate, and is adhered with an adhesive on one side of the film substrate.

[0013]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a plan view of a flat film according to the present invention.

FIG. 1 is a cross-sectional view showing an embodiment of the flat film according to the present invention.

The flat glue film 1 according to the present invention has a film substrate 2 on one side of which a removable adhesive 3 made of small adhesive particles is applied.

In the drawing, reference numeral 4 denotes a release paper.

The film substrate 2 has tints 21 formed in a diazo sensitive material layer provided on a polyester film base of 50 μm to 200 μm.

This diazo sensitive material layer is about 10 μm.

The tint 21 has a dot percentage and a screen ruling usually used in photolithography.

The dot percentage and the screen ruling are respectively
5%, 10%, 20%, 30%, 40%, 50%, 60
%, 70%, 80%, 90% and 100L, 133L,
150L and 175L.

The layer of the pressure-sensitive adhesive 3 is obtained by applying a pressure-sensitive adhesive composed of small acrylic tacky particles to a thickness of 10 μm to 30 μm.

The release paper 4 is formed by applying a release agent to one side of paper such as kraft paper or gramine paper or a film such as polyethylene terephthalate.
A thickness of 0μ is desirable.

When performing the netting work, the flat netting film 1 is directly overlaid on a mask plate or a negative plate, and is adhered with an adhesive 3 on one side of a film substrate 2.

Therefore, the flat net film 1 of this invention is
Does not require adhesive tape.

Further, since it can be directly pasted on a mask plate or a negative plate, it can be easily angled and positioned.

Further, since the pressure-sensitive adhesive 3 is composed of small-sized tacky particles, no air bubbles enter during the application.

Next, an actual example and a comparative example using a conventional method will be described in comparison.

As the flat net film 1 of the present invention, the following one was formed.

As the film substrate 2, a 10 μm diazo photosensitive material layer is provided on a 75 μm polyester film, and the diazo photosensitive material layer has a dot area of 30% and 50%.
The one having a screen ruling of 33 L was used.

On the opposite side of the film substrate 2 from the dot, an alkyl acrylate having an alkyl group having 4 to 8 carbon atoms, methyl acrylate, methyl methacrylate,
Solution polymerization of styrene vinyl acetate, vinyl propionate, etc., and then dispersing in water to form a suspension. Apply an acrylic adhesive consisting of small adhesive particles to a thickness of 20μ. Thus, a layer of the pressure-sensitive adhesive 3 was formed.

Further, as release paper 4, 100 μm of clasin paper coated with polyethylene and coated on one side with a silicone release agent was used.

Then, the layer of the pressure-sensitive adhesive 3 and the surface of the release paper 4 on the side of the silicone release agent were laminated together.

Further, this was cut into sheets to obtain two types of flat black films 1 having predetermined halftone dots of 30% and halftone dots of 50%.

Thereafter, using the flat thin film 1 of the present invention and the conventional flat thin film, a flat thinning operation described below was performed, respectively.

The characters to be concealed are katakana a and b. The size of the characters is 20 mm square and the character interval is 5 m.
m.

A film of the original is photographed to form a negative mask plate in which the characters "a" and "a" are blank. And a conventional flat laying-down operation using a flat lining film.

Printing is performed in black color, and the screen angle is 45.
°.

The character "a" has a dot of 30%, and the character "a" has a dot of 50%.

In the case of the conventional flat-blanking work using a general flat-blanked film, the required size is cut out from 30% and 50% of the flat-blanked film in accordance with the size of the character, and the above-mentioned negative is cut out. It was pasted on a mask-like plate and fixed with an adhesive tape.

However, since the character spacing is as narrow as 5 mm,
Since the adhesive tape was not sufficiently pasted, the adhesive tape was stuck on a character of a flat film, and it was difficult to set an angle. % Dot) was 52 °, and the letter A (50% dot) was 38 °.

For this reason, the mark of the adhesive tape was reflected on the character after reversing the film to the silver halide film, and no good quality was obtained.

On the other hand, since the flat net film 1 of the present invention is provided with the pressure-sensitive adhesive 3, the angle setting and the positioning were easy.

Since no adhesive tape is required, no trace of the adhesive tape appears on the silver halide film after reversing.

Further, since the pressure-sensitive adhesive 3 was composed of small pressure-sensitive adhesive particles, air bubbles did not enter when the adhesive was applied.

[0045]

As described above, according to the present invention, the work of attaching the flat halftone film in the flat halftone step is simple.

In addition, in the case of overprinting of two or more colors, it is possible to improve the accuracy of adjusting the screen angle of the flat halftone film for each plate, and to prevent the occurrence of moire.

Further, since the adhesive made of the adhesive fine particles which can be peeled off is used, it is possible to prevent the bubbles from being entangled at the time of application.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view showing one embodiment of a flat film according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF REFERENCE NUMERALS 1 flat film 2 film base material 3 adhesive

Claims (1)

(57) [Scope of request for utility model registration] 1. A flat netting film used in a flat netting step in photoengraving, wherein a removable adhesive is applied to one side of a film substrate.