JPH03158841A - Close contact exposure device - Google Patents

Abstract

PURPOSE:To prevent an original and a photosensitive material from being deformed or damaged and to obtain a clear image by specifying the specific surface resistance of a shielding member to be moved from an original platen aperture part. CONSTITUTION:The close contact type exposure device having a photosensitive material tray to be relatively moved from the original platen having an aperture part and the shielding member to be moved from the original platen aperture part is constituted so that the specific surface resistance of the shielding member is <= 1.0 X 10<12>OMEGA.cm, preferably <= 5.0 X 10<11>OMEGA.cm, at the time of normal temperature and humidity conditions in order to prevent the generation of electrostatic charge on the original. Thereby, it is necessary to constitute at least the face being in contact with the original out of the shielding member of a conductive member. Therefore, conductivity is imparted to the whole shielding member or the surface of the shielding member or the whole surface of the shielding member is converted with a conductivity imparting sheet or the like. When the surface of the shielding member is rugged, the sliding property of the shielding member on the surface of an original film can be improved and the original film can be prevented from being deformed or damaged due to a hitch.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a contact exposure apparatus, and more specifically, it relates to a contact exposure apparatus that uses spectral exposure.
! (Place each printed color separation original film (hereinafter also simply referred to as original) accurately in a predetermined position and place it on a positive; color or negative color photosensitive material 4 for each original. This invention relates to an improvement in an exposure device, which is a technology for directly inspecting the presence or absence of abnormalities in a final document for producing a printing plate by repeatedly exposing it multiple times to produce a color image copy with the same color scheme as the print finish.

[Prior Art] Conventionally, exposure devices have two types of exposure devices: those that irradiate light from a light source onto the surface of a document and form an image on a photosensitive material using a projection lens that has the function of enlarging, reducing, or equal magnification; There is a method in which materials are overlapped and irradiated with light from a light source for close exposure.

In addition, there are scanning exposure and static exposure methods for irradiating light source light, and the former requires a small light source to create a compact exposure device, while the latter requires a fairly large light source, resulting in a large exposure device. .

In the plate inspection process, multiple originals of printing plates for color printed matter are stacked one by one on a color photosensitive material using an exposure device to check the authenticity of the originals.

The image is exposed sequentially to create an image with the same color tone as the printed material, and then inspected to see if it is as intended.

The exposure equipment used in this process uses a projection lens to take pictures, and although it is quite large, it is possible to work in a bright room.

On the other hand, the contact exposure method uses color photosensitive material.
Since the original is directly placed on the first floor and exposed, the reproducibility of one gradation is greatly improved.

However, since color photosensitive materials have a photosensitive region in the entire visible range, it is impossible to handle them in a bright room, and they are forced to grope around in a dark room.

Therefore, the work of setting the original film at a specific position on the document table is done by a person in a bright room, and the setting of the photosensitive material at a specific position on the 11 table is done automatically by a machine that creates a dark room and exposes it. A contact exposure device with improved workability that solves the above problem by automatically forming a dark room in both systems and holding the original film and photosensitive material on one plane is a product of Konica Co., Ltd. Name: Konsensux I
I) and Fuji Photo Film Co., Ltd. (Product name: FINE C
Currently available from HECKER.

These apparatuses include a document table having an opening, a photosensitive material mounting table movable relative to the document table and fitable into the opening, and a light shielding table movable with respect to the document table opening. A contact exposure device having a member, when multiple exposure is performed from a plurality of originals, when the originals are replaced, the photosensitive material! ! Position the stand so that it does not touch at least the light shielding member surface.1.
The light-shielding member is fitted between the document table and the photosensitive material mounting table to maintain the photosensitive material within the light-shielding portion, thereby making it possible to operate in a bright room.

However, in these devices, when the light-shielding member is inserted, dirt and dust are attracted to the image due to static electricity generated between the light-shielding member and the document or the cover sheet used as the adhesion assisting member. Not only does this have a negative effect, but when the static electricity is strong, the document has the disadvantage of being pulled, deformed, and even damaged.

In addition, if the light shielding member has poor slipperiness, not only the original but also
It has the disadvantage that it can catch on the photosensitive material, deform it, and even damage it.

Particularly when the light shielding member is moved back and forth slowly in order to make the device more compact, it may move against the fixed end used to position the original, and catching or sticking becomes a serious problem. There is.

[Object of the Invention] Therefore, an object of the present invention is to provide a contact exposure apparatus that can prevent deformation and damage to originals and photosensitive materials, and can obtain clear images.

[Means for Solving the Problems] In order to achieve the above object, the present inventors have made extensive studies and have arrived at the present invention.

That is, the contact exposure apparatus according to the present invention includes a document table having an opening, a photosensitive material mounting table which is movable relative to the document table and can be fitted into the opening, and a photosensitive material mounting table which is movable relative to the document table and can be fitted into the opening. and a movable light shielding member, in which the surface resistivity of the light shielding member at room temperature and normal humidity is 1. It is characterized by being less than OX 1012Ω・C.

Further, in a preferred embodiment of the contact exposure apparatus according to the present invention, the surface of the light shielding member is roughened,
Preferably its surface roughness.

The surface roughness (Ra) is 0.1 to JIS-8-801.
It must be 5.0 μm.

[Structure of the Invention] In the present invention, the light shielding member is positioned so that the photosensitive material mounting table and the photosensitive material on the mounting table are placed under the dark room while the document table having the opening is under the bright room, When the document table is placed under a dark room, the dark room where the document table is located and the dark room where the photosensitive material loading table is present become one continuous space, and the original film on the document table and the photosensitive material on the photosensitive material loading table are brought into close contact with each other. Move as shown.

To this end, the light-shielding member may be installed on the document table, or it may be provided in the dark box where the photosensitive material mounting table is located so as to correspond to the opening of the document table when the document table is placed under a dark room. □ May be equipped for the opening.

The document table having the opening may be fixed to the dark box where the photosensitive material a placement table is located, or it may be movable. Of course, the opening of the dark box (equipped with a light-shielding member) where the photosensitive lumber and stand is located may be used as the opening of the document stand.

In this specification, "under dark room" or "rnIj box" means
This is a space that is shielded from light in the close-contact exposure neck device according to the present invention.

When exposure is performed, the original table and the photosensitive material plate 4 and the drafting table come close together so that the original and the photosensitive material plate 4 are in close contact with each other, and when the exposure is finished, they are separated so that a light shielding member is inserted between them. This movement is caused by the photosensitive material '1. This may be performed by moving only the LAN table, only the document table, or both.

In order to prevent electrostatic charging with the original, the surface resistivity of the light shielding member at room temperature and humidity is 1. OX 1012Ω・0m or less,
More preferably 5. Constructed with OX・1011Ω・0m or less. The normal temperature φ normal humidity here means a temperature of 23±2° C. and a humidity of 50±5%. In addition, in the one-piece configuration, at least the surface of the light shielding member that contacts the document needs to be made of a conductive member. Therefore, the entire light shielding member may be made of a conductive member, and the surface of the 1g light member may be made of a conductive member. Plastic materials or materials that may be processed to impart conductivity, or may have a conductivity imparting sheet, film, cloth, etc. applied to the entire surface.
For methods of imparting electrical conductivity, please refer to ``Prevention of static electricity in plastic films'' by Shigeyoshi Tachibana, published by Nikkan Kogyo Shimbun, ``Antistatic technology and market conditions for plastic films''.
More details can be found in literature such as New Edition of Polymer Market Research, ``New Technology for Imparting Conductivity to Polymers,'' edited by Conductive Polymer Materials Research Group 4, and Published by Chubu Business Development Center Publishing Department. In addition, specific materials include 1, for example, various rubbers kneaded with carbon black or metal powder, films processed by vapor-depositing metals on the surface or providing conductive latex layers, conductive plastic films, conductive Examples include various members in which a conductive paint is applied to the surface of a cloth woven from #a fibers.

In addition, in order to improve the sliding properties between the light shielding member and the document and reduce sticking and catching on the document, the surface of the light shielding member is roughened, and the surface roughness is JIS-1.
Based on BJOI (center line average roughness (Ra) is 0.1 to 5.
0 gm, more preferably 0.1 to 5.0 pot m,
Further, it is preferable that the maximum roughness (Rmax) is less than or equal to 1O.

To roughen the surface of the light shielding member, any of electrical treatment, physical treatment, or chemical treatment may be used, and two or more of these treatments may be used in combination.

Specifically, the surface is grained, pressed, plasma irradiated, or treated with chemicals such as acid, or the constituent material contains or contains a matting agent such as polymethyl methacrylate resin or silica. or roughen the surface by molding during manufacturing of light shielding materials,
Various known methods include roughening the surface by embossing.

[Effects of the Invention] According to the present invention, the light shielding member has a surface specific resistance! ,0XIQI
By basically being composed of materials with a resistance of 2Ω/0m or less,
The sliding property between the original and the cover sheet is improved, and static electricity is significantly reduced, so that it does not affect the image.

Furthermore, if the surface of the light shielding member is roughened, it will have good sliding properties with respect to the original film, and the original film will not be caught and will not be deformed or damaged.

[Experiment example] The following is a contact exposure apparatus manufactured by Konica Corporation (product name: Ko
nsensus II) as the light shielding member,
Experiments were conducted using two types of Tetron cloth: one whose surface was coated with a nitrile rubber resin, and another whose surface was coated with a carbon black-dispersed nitrile rubber resin. Note that the conductivity changes depending on the amount of carbon black introduced into the rubber.

In addition, CRHE film manufactured by Konica was used as the original film, and 100μ-PET was used as the cover sheet.
I used the base.

The surface specific resistance of each light shielding member is RO M, R-
Measured using a 503 type super megohmmeter. Further, the surface of each light shielding member was roughened, and the surface roughness (Ra) was set to 0.61 JLm.

The results are shown in Table 1.

Each symbol in the table indicates the following.

×: The light-shielding member has poor smoothness against the original film.
Static electricity was generated, which adversely affected the image.

Δ: The light-shielding member was slightly slippery with respect to the original film, and static electricity was likely to be generated depending on the insertion conditions of the light-shielding member (speed, etc.) and environmental conditions (environmental humidity, temperature, etc.), which tended to have an adverse effect on one image.

0: The light-shielding member has good sliding properties against the original film, and no generation of static electricity is observed.

There was no effect on the image.

0: The light-shielding member had good smoothness against the original film, no static electricity was observed, and there was no effect on the image.

Table 1 From Table 1, the surface specific resistance of the light shielding member is 1. OX101
By setting the resistance to 2 Ω·cw or less, the sliding property between the 1 g optical member and the original film is improved, and the generation of static electricity when the light shielding member is inserted can be prevented.

Therefore, it can be seen that the influence on one image can be eliminated.

Next, the surface resistivity of the above experiment No. 3 is 5 x 1ol
A similar experiment was conducted by changing the surface roughness (Ra) of the light shielding member of lΩ・cm, and the surface roughness (Ra) was O, Ip.
In the case of less than a (including the case where the surface remains glossy without being roughened), the original film may stick and be pulled, deforming or being damaged. Moreover, the surface roughness (Ra) is 5. O
When ILm was exceeded, the cut edge of the original film got caught, and the slipperiness worsened.

In addition, a polyethylene terephthalate film (surface specific resistance 102Ω・
C theory or below, surface roughness (Ra) below 0.02 #L-), and polyethylene terephthalate film coated with conductive latex on the surface (surface specific resistance 2.2X 1011Ω)
-cm, surface roughness (Ra) 0.07 g■).

When pasted on the nitrile rubber of Experiment No. 011,
As expected, the original film stuck together.

Claims (1)

[Claims] 1. A document table having an opening, a photosensitive material mounting table movable relative to the document table and fitable into the opening, and movable with respect to the document table opening. A contact exposure apparatus comprising a light shielding member, wherein the surface resistivity of the light shielding member at room temperature and normal humidity is 1.0×10^1^2 Ω·cm or less. 2. The contact exposure apparatus according to claim 1, wherein the surface of the light shielding member is roughened. 3. The contact exposure apparatus according to claim 2, wherein the light shielding member has a surface roughness (Ra) of 0.1 to 5.0 μm based on JIS-B-601.