JPS59223428A - Manufacture of photosensitive printing plate - Google Patents

Abstract

PURPOSE:To render pasteboard slippery and hardly electrostatically chargeable and further, easily strippable and to protect the surface of a photosensitive layer from damaging by laminating the pasteboard and the photosensitive layer and sand-wiching a specified solid powder between them. CONSTITUTION:Pasteboard is inserted into a photosensitive printing plate having a photosensitive layer on a support to form a laminate. At that time, a solid powder having 100-0.5mum diameter is attached to one of the surfaces of the pasteboard and said layer by coating or spraying to insert the powder between both. The following generally used matting agents are suitable for this solid powder: fine solid powders of SiO2, silica treated to make it hydrophobic, ZnO, TiO2, alumina, corn powder, starch, polystyrene, acrylic resin, PVC, phenol resin, etc. A preferable size is 0.5-50mum, and a preferable amt. to be added is 0.1-10g/m<2>.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a novel stacking method for stacking photosensitive printing plates.

Conventionally, photosensitive printing plates have been produced by coating various supports with a photosensitive structure material, cutting them into a specified size, and printing several sheets or tens of sheets.
It has been sold as a single unit package by stacking the sheets. At this time, in order to prevent the surface of the photosensitive layer from being damaged by scratching or friction, and to ensure smooth and accurate cutting to a certain size, a so-called mount is inserted to ensure close contact. 1. Materials used as mounts include paper, nonwoven fabric/plastic sheets, paper coated with synthetic resin on one or both sides, and waterproof paper impregnated with synthetic resin, wax, fatty acids, etc. was. Recently, paper coated with a synthetic resin on one or both sides, waterproof paper impregnated with a synthetic resin, or wax has been considered particularly suitable as a mount for a photosensitive lithographic printing plate. The reason for this is that it has the advantage of being able to cut a larger number of sheets at once compared to interleaving paper that is made only of paper, and that it does not introduce moisture to the surface of the photosensitive layer.

These interleaf sheets are placed between the printing plate and in order to prevent them from shifting, a high voltage is applied to the surface of the photosensitive layer to charge it before or after cutting during the manufacturing process of the photosensitive printing plate. They were in close contact.

However, in such cases, static electricity of a dangerous voltage remains on the stacked mounts, and the user often receives an electric shock during work or when using the mounts. Furthermore, the adhesion between the photosensitive printing plate and the entire paper is too good, making it difficult to peel off easily. Because they are pressed together with rollers, etc. when stacking them, the backing paper sometimes becomes wrinkled, and if stacked as is, the wrinkles that damaged the photosensitive layer and the wrinkled pattern will be transferred to the photosensitive layer, resulting in uneven development. There were drawbacks such as.

It is also known to spray a small amount of antistatic surfactant to prevent static electricity, but in this case, moisture remains on the surface of the photosensitive layer, and photosensitive layers that are mainly composed of diazo resin have poor storage stability. However, there were drawbacks such as slow development.

This is a method in which solid powder with a diameter of 100 .mu.m to 0.5 .mu.m is included between the interleaf paper and the surface of the photosensitive layer when the printing plates are stacked together with a mount.

According to the present invention, since the solid powder exists between the surface of the photosensitive layer of the photosensitive printing plate material and the interleaf paper, the backing paper is less likely to slip, and static electricity is also likely to occur, causing the user to feel an electric shock. It disappears. In addition, the mount is not fragile, so there is no need to damage the surface of the photosensitive layer. Furthermore, when stacking several sheets or tens of sheets and cutting them to a certain size with a guillotine,
This makes it easier to align the plate materials, and this also improves dimensional accuracy.

Another advantage is that when using the photosensitive printing plate according to the present invention, even when the mount is removed, some solid powder remains on the surface of the photosensitive layer, so that the original film and the surface of the photosensitive layer come into close contact under vacuum. When the film is exposed to light, it can be brought into close contact with the photosensitive layer in a short time, and static electricity is not generated between the film and the photosensitive layer surface, allowing for smooth film imposition. It also has the advantage that () is unlikely to occur.

As the solid powder used in the present invention, commonly used matting agents are suitable, such as silicon dioxide, hydrophobically treated silica powder, zinc oxide, titanium oxide, alumina, corn flour, starch, and polystyrene. , fine solid powders of acrylic resin, vinyl chloride resin, phenol resin, etc. are preferable. There is no particular limitation on the shape, but a spherical one is preferable, and the size is preferably 100μ to 0.5μ in diameter, particularly preferably in the range of 0.5 to 50μ, and the amount of F
io, the range of i to 10 is preferable. If the thickness and quantity exceed the above ranges, this powder will slow down the development process and may scatter during work or use, resulting in poor work environment hygiene.

Moreover, if it is less than the above range, it is the same as doing nothing, and the result is not suitable for the purpose of the present invention, so it is not preferable.

In the present invention, the solid powder may be contained between the surface of the photosensitive layer of the photosensitive printing plate and the mount, such as by air spraying, electrostatic spraying, etc. The solid powder can be sprayed in liquid form by mixing it with water or a fixed-term solvent, but it can also be applied dry with a brush or puff, or it can be mixed or dissolved in water or an organic solvent and applied by roller or extrusion. ,
Examples include methods such as dip coating or gravure roll coating, followed by drying to leave a solid powder.

The spraying, atomizing, or coating process differs depending on the case in which the photosensitive printing plate is manufactured, but if the support is in the form of a coil, it is carried out after the photosensitive layer has been applied and dried, and then the mount and mount are coated. Either cut them together, or cut them out and then match them with gold paper and stack them.

Another method is to spray or apply a solid powder on the surface of the photosensitive layer at a position after coating and drying the photosensitive layer, and before or after cutting the wound coil into a specified size. 1. At this time, the interleaf paper may have already been sprayed or coated with solid powder and adhered to it.

Even when manufacturing in sheets, the above-mentioned female opening <, when the interleaf paper is stacked, the surface of the layer may be electrocuted or! A solid powder is attached to the surface of the interleaf paper that will be adhered to the surface of the iR light layer, and then the sheets are overlapped.

The photosensitive printing plate in the present invention basically includes a photosensitive layer provided on a support, a lithographic printing plate,
Includes 11 printing plates such as letterpress printing plates and intaglio printing plates.

Supports include dimensionally stable plate-like materials conventionally used as supports for printed matter, such as paper, plastic-laminated paper, aluminum (including aluminum alloys), ), metal plates such as zinc, iron, copper, and chromium, and multilayer plates of these metals, and plastic films such as polyethylene and polypropylene;
C paper, plastic film, etc. are preferable.

The support is surface-treated if necessary. For example, in the case of photosensitive lithographic printing plates, aluminum (.

7/lzl commim alloy) plates and supports having a hyaluminum surface are often used, and in this case, known techniques such as graining, anodizing, hydrophilic treatment, etc. can be used.

There are no particular restrictions on the photosensitive composition provided on the support, and there are many types such as those based on known photosensitive diazo compounds and those based on photopolymers. There is a distinction between positive type and negative type, but both can be used to form the photosensitive layer of the printing plate material of the present invention.
1 Example 1 Thickness 0.2516. A coiled aluminum plate having a width of 1003 mb was subjected to graining, anodizing treatment, hydrophilic treatment, etc. using known techniques, and then a photosensitive composition mainly containing an orthoquinone diazide compound was applied. This width is 800
WI1. The photosensitive layer is cut to size, and then a solid powder of corn powder with a diameter of 15 to 20 μm is sprayed onto the surface of the photosensitive layer using a spray nozzle in a quantity of 1 to 2 inches. Pauno so that it becomes;
It was ringed. Next, about 1000 sheets of mount paper coated with polyethylene on one side were inserted so that the polyethylene-coated surface of the mount paper was in close contact with the powdered photosensitive layer surface. This photosensitive printing plate C I is designated as (1).

For comparison, about 1,000 sheets were stacked in the same manner, with no powdering on the surface of the photosensitive layer, and a full electric field was generated between this plate and the interleaving paper to bring them into close contact. A comparative test using (1) and (11) using this photosensitive printing plate sheet as 01) was as follows.

Sheet (1) was easy to peel off when removing the mount, did not generate static electricity, and did not receive an electric shock. Next, (9) each sheet moved easily when it was packaged one by one, so it was easy to arrange them. Also, the sheet (
When 1) was actually used, it took 6 seconds for the positive film to be vacuum-adhered and for the air to completely escape.

C) (It) felt a lot of electric shock when he touched the aluminum because there was static electricity left when he removed the interleaving paper. In addition, the mount sticks to the surface of the photosensitive layer and is difficult to remove, and if you forcefully remove the mount, static electricity will be generated there.
At this time, I also felt an electric shock. When packaging 30 sheets of MafC, each sheet did not move easily and alignment was slow. It took ω seconds to vacuum-adhere this sheet to the film.

0 Example 2 A photosensitive composition mainly composed of diazo resin was applied to an aluminum plate pretreated in the same manner as in Example 1. After cutting this, a mount (paper coated with polyethylene on both sides with polyethylene) is prepared by powdering solid powder on the surface that is in close contact with the photosensitive layer surface Z, f
A total of about 1,000 sheets were stacked. This time, the paraj'' ringed solid powder was made of silicon dioxide with a diameter of 5 to 10 μm, and was made to have a quantity of 2 to 3 f/n. This photosensitive printing plate sheet was referred to as (1).

For comparison, the same interleaf paper without powdering is about 1
000 sheets were stacked. This photosensitive printing plate sheet (V)
shall be.

A comparative test of sheet 01 [) and sheet (IV) at the time of use 1- is as follows.

C) 011) is C) As in case of (1), the interleaving paper is easy to peel off and there is no electric shock! <, The photosensitive layer was not damaged, and the plate was easy to move, making it easy to cut into small pieces. Also, the time required for the negative film to be brought into close contact with the film in vacuum is (capital) seconds. Sheet + IV), starting from the Ith sheet from the top, was so heavy that the interleaving paper stuck tightly to the surface of the photosensitive layer, making it difficult to peel off, and when I forcibly peeled it off, static electricity was generated and I received an electric shock. Further, at this time, the surface of one photosensitive layer was scratched, and the photosensitive film was peeled off to some extent. Furthermore, when cutting into smaller sizes, it was difficult to align the attachments and the work efficiency was poor. The time required to vacuum adhere the negative film was 65 minutes.
It was seconds.

As can be seen from the above comparative test results, if the stacking method of the photosensitive printing plate manufacturing method according to the present invention is used, you will not feel an electric shock due to static electricity during work or use, and there will be no damage to the photosensitive layer. The interleaving paper can be easily removed without any problems, and the attachments are easy to align. Moreover, the time required for vacuum-adhering the film and sheet could be shortened.

Claims (2)

[Claims] (1) When stacking a photosensitive printing plate that has a photosensitive layer on a support with interleaf paper, apply hard P powder with a diameter of 100μ to 0.5μ on either the backing paper or the surface of the photosensitive layer. A method for stacking photosensitive printing plates, etc., characterized by interposing solid powder between the two by spraying or spraying. (2) The scope of claims characterized in that the interleaving paper uses a plastic film sheet, paper coated with synthetic resin on one or both sides, paper impregnated with synthetic resin, wax, fatty acids, etc. The method described in paragraph 1.