JPH11119445A - Original film setting device for photomechanical process - Google Patents

Abstract

PROBLEM TO BE SOLVED: To facilitate the formation of a film attraction peripheral groove for attracting the original film on a glass plate in an original film setting device for photomechanical process. SOLUTION: This device is constituted by integrating the glass plate 15 with a hollow section of a frame body 11 being hollowly formed, and providing the film attraction peripheral groove 17 in an endless shape for attracting the original film 18 between an outer circumferential edge section of the glass plate 15 and the inner circumferential edge section of the frame body 11. The device is provided with an elastic sealing rubber 22 for retaining the attraction force on the frame body 11 at the peripheral side of the film attraction peripheral groove 17. The device is allowed to expose by holding the sealing rubber 22 in close contact with the original film 18, and moreover holding the original film 18 in close contact with a photosensitive surface on a PS plate kept in standby state on the lower side.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an original film setting device in photolithography.

[0002]

2. Description of the Related Art For example, when producing a printing plate used for offset printing of a newspaper or the like, a presensitized plate (hereinafter referred to as a presensitized plate) having a photosensitive film formed by applying a photosensitive liquid on a plate material in advance. This plate is called a “PS plate”), and a photoengraving technique is used in which an original film is brought into close contact with the photosensitive film of the PS plate and exposed, and an image including characters and the like is printed to create a printing plate. Have been.

As shown in FIG. 7, conventionally, a film suction peripheral groove 2 is provided along the periphery of a transparent glass plate 1 on the lower surface thereof in an endless manner. The original film 3 is held by suction on the lower surface of 1,
The original film 3 of the transparent glass plate 1 is placed on the photosensitive surface of the PS plate 5 placed on the upper surface of the elastic mat 4 located below.
Is lowered to contact the photosensitive film of the PS plate 5 through the original film 3 by a light source (not shown) located above the transparent glass plate 1.

[0004]

It is not easy to form the film suction peripheral groove 2 along the peripheral edge of the transparent glass plate 1 as in the prior art.

[0005] Furthermore, on the elastic mat 4,
When the PS plate 5 is loaded and unloaded, the PS plate 5 is
And the PS plate 5 is difficult to move.

On the other hand, when the PS plate 5 is supported by a hard plate, the adhesion between the original film 3 and the PS plate 5 which is adsorbed to the transparent glass plate 1 by the film-adsorbing circumferential groove 2 is ensured. difficult.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to facilitate the formation of a film suction circumferential groove for sucking an original film, and to further support a printing material on a hard printing plate. It is an object of the present invention to ensure that the adhesion between the original film and the plate material can be ensured even in such a case.

[0008]

According to the first aspect of the present invention, an original film is brought into close contact with a photosensitive surface of a plate material on which a photosensitive film is formed, exposed to light, and an image is printed to form a printing plate. In photoengraving, a hollow frame, a transparent plate integrated into the hollow portion of the frame, and an endless portion provided between the outer peripheral edge of the transparent plate and the inner peripheral edge of the frame. And a film adsorbing peripheral groove for adsorbing the original film.

In the exposure process, the original film is suction-held from the transparent plate to the frame by a film suction peripheral groove between the outer peripheral edge of the transparent plate and the inner peripheral edge of the frame.

According to a second aspect of the present invention, there is provided an original film setting apparatus for photoengraving according to the first aspect, wherein the original film is provided endlessly on a frame at an outer peripheral side of the film suction peripheral groove. And a sticking force holding seal material having elasticity to hold the holding force.

When the original film is attracted to the transparent plate by the film-adsorbing peripheral groove, the invasion of air from the outside into the film-adsorbing peripheral groove is prevented by a sealing material for retaining the adsorbing force, and the original film is attached to the transparent plate. Securely hold by suction.

According to a third aspect of the present invention, there is provided an original film setting apparatus for photoengraving according to the first or second aspect, wherein a hard plate supporting a plate material on a side opposite to the original film; A plate surface film suction groove is provided on the surface of the plate opposite to the original film protruding from the plate material and is adapted to suck the original film.

Even when the original film is supported by a hard plate, the original film is sucked by the plate surface film suction groove, and the original film is brought into close contact with the plate material.

According to a fourth aspect of the present invention, in the apparatus for setting an original film in photoengraving according to the third aspect, the film suction peripheral groove is moved in conjunction with the original film suction by the plate surface film suction groove, and This is to release the suction of the film.

At the time of exposure, the original film is suctioned by the plate surface film suction groove, and at the same time, the suction of the original film by the film suction circumferential groove is released.
The original film is brought into close contact with the plate material and the plate by the suction force on the plate side and the atmospheric pressure from the opposite side. At that time, the invasion of outside air into the plate surface film suction groove is prevented by the film pressure on the plate material and the plate by the suction force holding sealing material,
Ensures close contact between the original film and the plate material.

According to a fifth aspect of the present invention, there is provided an original film setting apparatus for photoengraving according to the fourth aspect, wherein the negative pressure is formed on a part of the film facing surface of the frame to maintain a negative pressure for attracting the film. A pressure maintaining region and a frame surface film suction portion provided in the negative pressure maintaining region of the frame surface for sucking the original film.

Even when the film suction peripheral groove is switched from a state in which the original film is sucked to a state in which the original film is not sucked, a part of the original film is always sucked to the frame surface by the frame surface film sucking portion in the negative pressure maintaining area. Hold to prevent misalignment of the original film.

[0018]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to FIG.
This will be described with reference to FIGS.

As shown in FIGS. 1 to 4, reference numeral 11 denotes a hollow frame made of aluminum or the like, and an inner peripheral edge of the frame 11 facing the hollow portion 12 has an upper half convex portion. 13
Are integrally formed, and a cutout recess 14 is formed in the lower half.

A peripheral edge of a glass plate 15 as a transparent plate is formed on the lower surface of the projection 13 by a chemical bonding means such as an adhesive or a mechanical connection such as a screw so as to fit into the cutout recess 14 of the frame 11. By means of a sealing means 16 such as silicon rubber filled between the inner peripheral surface of the convex portion 13 and the corner of the glass plate 15, the airtightness between the convex portion 13 and the glass plate 15 is improved. Is held.

By providing a uniform gap over the entire circumference between the outer peripheral edge of the glass plate 15 and the inner peripheral edge of the cutout recess 14 of the frame 11, a film-adsorbing peripheral groove opened downward. 17 is formed endlessly.

The film suction circumferential groove 17 is selectively connected to a vacuum pump (not shown) or the atmosphere by a pipe line and a switching valve (not shown) (not shown). The original film 18 is sucked and held by the negative pressure generated in the suction circumferential groove 17, and when connected to the atmosphere, the sucking of the original film 18 by the negative pressure is released.

On the outer peripheral side of the film suction peripheral groove 17,
A seal material fitting groove 21 having a semicircular cross section is provided on the entire lower surface of the frame body 11, and a seal rubber 22 serving as a sticking force holding seal material having a circular cross section having elasticity is provided in the seal material fitting groove 21. It is fitted. The seal rubber 22 may be a tube.

As shown in FIG. 1, one side of a seal rubber 22 arranged along four sides of the frame 11 and a lower surface of the frame 11 also arranged in parallel along the one side. A negative pressure maintaining region 24 for maintaining a negative pressure for adsorbing a film is formed on the film facing surface, that is, a part of the lower surface of the frame 11 by the seal rubber 23 fitted to the frame 11.

A pair of pins 25 for positioning and fixing the original film 18 are provided on one side and the other side of the negative pressure maintaining area 24, and these pins 25 are provided with positioning holes (see FIG. (Not shown).

As shown in FIGS. 2 and 3, a plurality of frames as a frame surface film sucking portion for constantly sucking and holding one side of the original film 18 are provided in the negative pressure maintaining region 24 on the frame surface. A body film suction groove 26 is provided, and the frame body film suction groove 26 is connected to a vacuum pump (not shown) through a pipe and a switching valve (not shown), and except when the original film 18 is removed from the glass plate 15. The negative pressure maintaining region 24 surrounded by the seal rubbers 22 and 23 on the surface of the frame is maintained at a negative pressure.

It should be noted that a porous sintered metal may be buried in the lower surface of the frame 11 and connected to a vacuum pump instead of the frame-surface film suction groove 26 as the frame-surface film suction portion.

As shown in FIGS. 3 (B) and 4 (B), reference numeral 31 denotes a plate material on which a photosensitive liquid is applied in advance to form a photosensitive film, that is, a presensitized plate (hereinafter referred to as a presensitized plate). Plate is referred to as “PS plate”).
The S plate 31 is supported by a hard metal plate 32 located on the side opposite to the original film 18, that is, on the lower side.

The surface of the plate 32 facing the original film 18 protruding from the PS plate 31 is placed on the upper surface of the plate 32.
The plate surface film suction groove 33 for suctioning the printing plate is provided.
On the upper surface of the plate 32 surrounded by the plate surface film suction groove 33, a PS plate support surface 34 having a suction groove (not shown) for sucking and fixing the PS plate 31 is formed.

The plate surface film suction groove 33 is selectively communicated with a vacuum pump (not shown) or the atmosphere by a pipe line and a switching valve (not shown). When the communication is established, the negative pressure is released.

The seal rubber 22 is in close contact with the original film 18 so that when the film suction circumferential groove 17 is made to have a negative pressure, the sealing force is maintained by the negative pressure and the original film 18
When the plate is brought into close contact with the plate 32 and the plate surface film suction groove 33 is set to a negative pressure, the suction force by the negative pressure is maintained.

As shown in FIGS. 5 and 6, the plate surface film suction groove 33 is formed so as to surround the PS plate 31 formed in a long length. It has a surface 31A and another exposure surface 31B.

On the other hand, the endless seal rubber 22
Since the original film 18 is pressed against the PS plate 31 at an intermediate position of the PS plate 31 which cannot be surrounded by the plate surface film suction groove 33, the adhesion between the original film 18 and the PS plate 31 can be secured. By maintaining the airtightness during that time, air suction by the plate surface film suction groove 33 can be efficiently performed in a short time.

As shown in FIGS. 3B and 4B, the film suction peripheral groove 17 is
The communication destination is switched from the vacuum pump to the atmosphere by a switching valve (not shown) in conjunction with the suction of the original film 18 by the, and the original film 18 is brought into close contact with the PS plate 31 and the plate 32 by the air.

Next, the operation of the illustrated embodiment will be described.

As shown in FIGS. 3A and 4A, the film suction circumferential groove 17 formed between the outer peripheral edge of the glass plate 15 and the inner peripheral edge of the frame 11 is connected to a switching valve. To the vacuum pump, and the film suction circumferential groove 17
The original film 18 is held by suction on the lower surface of the document 15.

At this time, invasion of air from the outside into the film suction peripheral groove 17 is prevented by the close contact between the frame 11 and the original film 18, but is more reliably prevented by the close contact between the seal rubber 22 and the original film 18. Thus, the original film 18 can be reliably held on the glass plate 15 by the negative pressure of the film suction circumferential groove 17.

On the other hand, on the lower side, the plate surface film suction groove 33
The PS plate 31 is carried into the PS plate support surface 34 of the plate 32 surrounded by.

Then, by lowering the frame 11 or raising the plate 32, as shown in FIGS. 3 (B) and 4 (B), the PS plate 31 having the photosensitive film formed thereon is exposed to light. The original film 18 is brought into contact with the surface.

At this time, the communication destination of the plate surface film suction groove 33 is switched from the atmosphere to the vacuum pump by the switching valve, and the original film 18 is sucked to the photosensitive surface of the PS plate 31 by the plate surface film suction groove 33.

When the communication destination of the film suction circumferential groove 17 is switched from the vacuum pump to the atmosphere by a switching valve in conjunction with the operation of sucking the original film 18 onto the PS plate 31, the film suction circumferential groove 17 Releases adsorption of 18 and receives supply of air.

By such air pressure switching, the suction force for sucking the original film 18 downward by the plate surface film suction groove 33 and the atmospheric pressure introduced to the upper surface of the original film 18 via the film suction peripheral groove 17 And the original film 18 is PS
The plate 31 and the plate 32 can be pressed and brought into close contact with each other.

On the other hand, when the original film 18 is sucked and held on the glass plate 15 shown in FIG. 3A and FIG.
4 (B) and the exposure shown in FIG. 4 (B), a part of the original film 18 is always sucked and held on the surface of the frame so that the pins 25 and the positioning holes of the original film 18 are kept fitted. Prevent the displacement of 18.

When performing the exposure treatment, a glass plate
The photosensitive surface of the PS plate 31 is exposed through the original film 18 by a light source located above the plate 15, and an image is printed on the photosensitive surface to produce, for example, a printing plate for offset printing.

At this time, the original film 18 pressed and adhered to the upper surfaces of the PS plate 31 and the plate 32 by the seal rubber 22 and the atmospheric pressure can hold the suction force of the plate surface film suction groove 33, and the original film 18 and the PS plate Since the adhesion with the photosensitive surface of No. 31 can be ensured, it is possible to prevent defects such as "burn out" which occur when the adhesion at the time of exposure is impaired.

FIGS. 5 and 6 show a case in which the exposure is performed on one exposure surface 31A of the PS plate 31 and then on the other exposure surface 31B, and the one exposure surface 31A of the PS plate 31 is exposed. 5, the original film 18 is set at the position shown in FIG. 5 and the original film 18 is pressed from above by the seal rubber 22 positioned so as to surround one of the exposure surfaces 31A of the PS plate 31.
The original film 18 is pressed onto the plate 31 and the plate 32, and is sucked downward by the one plate surface film suction groove 33 located in the area under the seal rubber 22 under the original film 18.

When exposing the other exposure surface 31B of the PS plate 31, the original film 18 is moved to the position shown in FIG. 6 and the seal rubber 22 is positioned so as to surround the other exposure surface 31B of the PS plate 31. The original film 18 from the upper side to the PS plate 31
Press on the platen 32
The original film 18 is sucked downward by the other plate surface film suction groove 33 located in the area pressed by the seal rubber 22 below.

On the other hand, while the original film 18 is set at a fixed position and the PS plate 31 is moved,
And the positional relationship shown in FIG. 6 may be obtained.

As described above, even when the original film 18 is supported by the hard plate 32, the original film 18 is pressed from above by the seal rubber 22 and is sealed within a predetermined area in the plate surface film suction groove.
Because the film is sucked by 33, the whole original film 18 is PS plate
31 can be effectively adhered.

The film suction peripheral groove 17 not only releases the film suction at the time of exposure, but also positively supplies air under pressure by, for example, communicating with a pneumatic pump through a switching valve. The original film 18 may be pressed against the PS plate 31 and the plate 32 by the air pressure acting on the upper surface of the original film 18 from the circumferential groove 17. Air leakage at that time is prevented by the seal rubber 22.

[0051]

According to the first aspect of the present invention, since the film-adsorbing peripheral groove for adsorbing the original film is provided endlessly between the inner peripheral edge of the frame and the outer peripheral edge of the transparent plate. It is not necessary to groove the film suction peripheral groove on the transparent plate, and the film suction peripheral groove can be easily formed.

According to the second aspect of the present invention, the frame is provided with a sticking force holding sealing material having elasticity for holding the sucking force in close contact with the original film on the outer peripheral side of the film sucking peripheral groove. When the original film is attracted to the transparent plate by the film suction peripheral groove, air can be reliably prevented from entering the film suction peripheral groove from the outside by the suction force holding seal material when the original film is attracted to the transparent plate by the film suction peripheral groove. Can be reliably held by suction.

According to the third aspect of the present invention, the original film protruding from the plate material is sucked by the plate surface film suction groove provided on the plate, and the original film can be brought into close contact with the plate material.

According to the fourth aspect of the present invention, the film suction peripheral groove releases the suction of the original film in conjunction with the suction of the original film by the plate surface film suction groove.
The original film can be securely brought into close contact with the plate material and the plate by the suction force of the plate surface film suction groove and the pressing force of the atmospheric pressure introduced on the opposite side. In particular, the original film can be securely brought into close contact with the plate material and the plate by the seal material for holding the suction force and the atmospheric pressure. Since it is possible to reliably bring the plate into close contact with the photosensitive surface of the plate material, it is possible to prevent defects such as "burn out" which occur when the adhesion at the time of exposure is impaired.

According to the fifth aspect of the invention, even when the film suction peripheral groove is switched from the original film suction state to the suction release state, a part of the original film is held by the frame surface film suction portion in the negative pressure maintaining area. Is always sucked and held on the surface of the frame, so that the displacement of the original film can be reliably prevented.

[Brief description of the drawings]

FIG. 1 is a bottom view of a frame and a transparent plate relating to an original film setting device in photolithography of the present invention.

FIG. 2 is a bottom view showing an enlarged part A of the frame and the transparent plate in FIG.

FIG. 3A is a sectional view taken along the line III-III of FIG. 1, showing a state in which the original film is attracted by the frame and the transparent plate.
(B) is a sectional view showing a state where an original film is set between the frame and the transparent plate, the plate and the PS plate.

FIG. 4A is a cross-sectional view taken along the line IV-IV of FIG. 1, showing a state in which the original film is attracted by the frame and the transparent plate.
(B) is a sectional view showing a state where an original film is set between the frame and the transparent plate, the plate and the PS plate.

FIG. 5 is a plan view showing a positional relationship among a document film, a sticking force holding sealing material, and a plate surface film suction groove when one of the exposure surfaces of the PS plate is exposed.

FIG. 6 is a plan view showing a positional relationship among a document film, a sticking force holding sealing material, and a plate surface film suction groove when the other exposure surface of the PS plate is exposed.

FIG. 7 is a cross-sectional view showing a document film setting device in a conventional photoengraving process.

[Explanation of symbols]

11 Frame 12 Hollow part 15 Glass plate as transparent plate 17 Film suction peripheral groove 18 Original film 22 Seal rubber as seal material for holding suction force 24 Negative pressure maintenance area 26 Frame body film suction groove as frame body film suction part 31 PS plate as a plate material 32 Plate plate 33 Plate surface film suction groove

Claims (5)

[Claims] 1. A photoengraving method in which an original film is brought into close contact with a photosensitive surface of a plate material on which a photosensitive film is formed, exposed to light, and an image is printed to form a printing plate. A transparent plate integrated with the hollow portion of the frame, and a film suction peripheral groove provided endlessly between the outer peripheral edge of the transparent plate and the inner peripheral edge of the frame to adsorb the original film. An apparatus for setting an original film in photoengraving. 2. A suction force holding sealing material which is provided endlessly on a frame on the outer peripheral side of the film suction peripheral groove and has elasticity to adhere to a document film and hold the suction force. 2. An apparatus for setting an original film in photoengraving according to claim 1. 3. A hard plate for supporting a plate material on the side opposite to the original film, and a plate surface film provided on a surface of the plate opposite to the original film protruding from the plate material for absorbing the original film. 3. A suction groove comprising: a suction groove;
An apparatus for setting an original film in the photoengraving described in the above. 4. The original in photolithography according to claim 3, wherein the film suction peripheral groove releases the suction of the original film in conjunction with the suction of the original film by the plate surface film suction groove. Film setting device. 5. A negative pressure maintaining region formed on a part of the film-facing surface of the frame for maintaining a negative pressure for attracting a film, and a frame provided in the negative pressure maintaining region on the surface of the frame for attracting a document film. 5. The apparatus according to claim 4, further comprising a body film suction unit.