JPH0825822A - Stencil printing plate - Google Patents

Abstract

PURPOSE:To obtain a printed matter in which a printing plate can be easily engraved without surface defect and which has excellent printing shape by using a ferrite or martensite stainless steel plate having surface mean roughness of a specific value or less as a board. CONSTITUTION:A copper-plated layer 3 for forming ink cells 5 via an etching stop layer 2 is provided on one side surface of a ferrite or martensite stainless steel plate 1 having surface mean roughness of 0.02mumRa or less, and the surface is covered with a hard chromium plating 4. Thus, since the one side surface of the plate 1 is regulated to the surface mean roughness of 0.02mumRa or less, the layer 2 and the layer 3 are flatly formed thereon, and a stencil printing plate having no surface defect such as a protrusion, a pit is engraved. Since the stainless steel plate having small linear expansion coefficient is used as the board 1, the dimensional change due to the head of the layer 3 formed with ink cells 5 is suppressed, and the change of the entire printing plate is reduced.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a color liquid crystal display device,
The present invention relates to a structure of an intaglio printing plate used when manufacturing a color filter used for a color image input / output device such as a color video camera and a color image sensor by offset printing.

[0002]

2. Description of the Related Art As an intaglio printing plate for printing and forming the above color filter, the intaglio printing plate shown in FIG. 2 is well known. That is, in the conventional intaglio printing plate, the ballad copper plating layer 6 is formed on one surface of the steel substrate 1 to a required thickness, for example, 30 to 50 μm, and an etching stop layer of nickel is formed on the copper layer. 2 through the groove-shaped ink cell 5
The copper plating layer 3 for forming
The hard chrome plating 4 is thinly coated on the surface to increase durability.

[0003]

In the conventional intaglio plate having the above structure, since the surface of the substrate is not sufficiently smooth, even if copper or the like is plated on it, unevenness tends to remain and the plate tends to have many surface defects. Is. Since the expansion coefficient of the substrate is large, it is difficult to obtain alignment accuracy, and it is difficult to manufacture a large color filter. Since there is also a ballad copper plating layer for eliminating surface defects under the copper plating layer forming the ink cell, it is impossible to measure the depth of the ink cell with an eddy current meter which is inexpensive and easy to operate. For this reason, it may be necessary to dispose of the product as a plate depth defect after plate making. There are various problems that the substrate is easily rusted and is difficult to store for a long period of time, and it has been a problem to solve these problems.

[0004]

In order to solve the above-mentioned problems of the prior art, the present invention has a surface average roughness of 0.02 μmRa.
On one surface of the following ferritic or martensitic stainless steel sheet, through an etching stop layer made of nickel or nickel alloy formed by electrolytic plating,
It is intended to provide an intaglio printing plate in which a copper plating layer for forming groove-shaped ink cells is provided and the surface is coated with hard chrome plating.

[0005]

Since the required one surface of the substrate is adjusted to have a surface average roughness of 0.02 μmRa or less, an etching stop layer made of nickel or a nickel alloy to be electroplated thereon and a copper plating for forming an ink cell. The layer is formed flat, and an intaglio printing plate having no surface defects such as protrusions and pits is produced. For this reason, a printed matter excellent in drawing accuracy and printing shape can be obtained.

Further, since a ferrite or martensitic stainless steel plate having a linear expansion coefficient smaller than the linear expansion coefficient of 11.8 × 10 ⁻⁶ / ° C. of a conventional steel substrate by about 10% or more is used as the substrate, Large linear expansion coefficient of 16.7 × 10 ^-6 / ° C laminated on the substrate, dimensional variation due to heat of the copper plating layer forming the ink cell is effectively suppressed, and variation of the intaglio printing plate as a whole Becomes smaller. This makes it possible to perform printing with high positional accuracy and to manufacture a large color filter having a large area.

[0007]

Embodiments of the present invention will now be described in more detail with reference to FIG. In addition, in order to facilitate understanding, FIG.
Also in the above, the same reference numerals are given to the portions having the same functions as the portions described in FIG.

The intaglio printing plate of the present invention illustrated in FIG. 1 (hereinafter, simply referred to as an intaglio plate) is an appropriate ferritic stainless steel polished to have a surface average roughness of 0.02 μmRa or less on a desired side, for example, On one surface of the substrate 1 made of SUS430, a copper plating layer 3 that surrounds a groove-shaped ink cell 5 via an etching stop layer 2 of a nickel alloy is provided,
This surface is thinly coated with hard chrome plating 4.

The intaglio plate having the above structure according to the present invention is formed by the following method. For example, the plate thickness is 3-10 mm
The surface average roughness of one side of commercially available SUS430 is about 0.02 μm using, for example, a nitric acid-alumina powder-based abrasive liquid (Mechanox CB-1 manufactured by Uemura Industry Co., Ltd.).
Chemical buffing is performed so as to be Ra or less.

A portion of the substrate 1 adjusted to the above properties other than the polished surface is masked with a non-conductive member such as PET film, and the composition is, for example, 300 g of nickel nitrate /
1, Nickelin (B-1) 200 ml / l, pH 1.4
Electroplating is performed under the conditions of a current density of 2 A / cm ² and a plating bath temperature of 60 ° C., and an etching stop consisting of a nickel-phosphorus alloy with a thickness of 3 μm (phosphorus 10% by weight, balance nickel). The layer 2 is formed on the smooth surface of the substrate 1.

Further, the substrate 1 having the etching stopper layer 2 formed on one side as described above is formed into a copper sulfate 200 composition.
Immersion in a plating bath of g / l, sulfuric acid 55 g / l, chlorine 70 ppm, electrolytic plating under conditions of current density of 2 A / cm ² and plating bath temperature of 25 ° C., and stopping etching of copper plating layer 3 having a thickness of 10 μm Formed on layer 2.

Then, a photosensitive resin (not shown) which is well known in the art (for example, PMER N-HC40 manufactured by Tokyo Ohka Co., Ltd.) is applied onto the copper plating layer 3, and mask exposure and development are performed. After the corrosion-resistant resist is formed in a desired pattern, ferric chloride solution (Baume concentration 40
The exposed portion of the copper plating layer 3 is etched by immersing the exposed portion of the copper plating layer 3 in a temperature of 35 ° C.) to form an intaglio ink cell 5 at a depth of 10 μm.
m to form a recess.

In the etching of the copper plating layer 3 with the ferric chloride solution, since the etching stop layer 2 made of a nickel-phosphorus alloy is disposed below the copper plating layer 3, the concave portion is formed by the copper plating layer. It is not formed deeper than 10 μm, which is the film thickness of 3.

Then, the above plate-shaped member having a groove-shaped recess on the surface is composed of chromic anhydride 250 g / l and sulfuric acid 2.5.
Immersion in g / l plating bath, current density 10A / cm
^2. Electroplating is performed under the condition of a plating bath temperature of 50 ° C., and the hard chrome plating 4 is thinly formed on the entire surface to a thickness of, for example, 3 μm to form the intaglio plate of the present invention.

In the intaglio plate having the above-mentioned structure, since the substrate 1 is made of ferritic stainless steel having a linear expansion coefficient smaller than that of the conventional carbon steel, there is an advantage that the alignment accuracy is improved.

That is, conventionally, the coefficient of linear expansion is 11.8 × 1.
0 ^-6 / ° C. of about had using carbon steel, linear expansion coefficient 1
By using SUS430, which is about 0.4 × 10 ⁻⁶ / ° C., which is about 12% smaller than that of carbon steel, the linear expansion coefficient is 16, which is laminated on the substrate 1 to surround the ink cell 5. The dimensional variation due to the heat of the copper plating layer 3, which is as large as 7 × 10 ⁻⁶ / ° C., is effectively suppressed, and the variation of the whole intaglio printing plate becomes small. This makes it possible to perform printing with high alignment accuracy and to manufacture a large-sized color filter having a larger area.

Further, as shown in Table 1, in the case of the intaglio plate of the comparative example in which the required average surface roughness of the substrate 1 was 0.03 μmRa after polishing a little, nickel to be electroplated on this was used. Alternatively, the etching stop layer 2 made of a nickel alloy and the copper plating layer 3 forming the ink cell 5 are unevenly formed to form a printing plate having many surface defects such as protrusions and pits, and the printing state is not good, In the intaglio plate of the present invention in which one side of the substrate 1 is adjusted to have a surface average roughness of 0.01 μmRa and 0.02 μmRa, and the plate is made,
The etching stop layer 2 made of nickel or nickel alloy to be electroplated thereon and the copper plating layer 3 to form the ink cell 5 are both flatly formed to form a printing plate without surface defects such as protrusions and pits. A printed matter excellent in drawing accuracy and print shape was obtained.

[0018]

[Table 1]

Further, unlike the conventional intaglio plate shown in FIG. 2, since the copper layer is only the copper plating layer 3, the copper plating can be performed by a nondestructive inspection using an eddy current meter which is inexpensive and easy to operate. The thickness of the layer 3 can be easily and accurately confirmed before the etching process. For this reason, it becomes clear that the depth of the ink cell 5 is insufficient after the plate making, and there is no inconvenience that the ink cell 5 must be discarded.

The color filter having a fine pattern offset-printed by using the intaglio plate of the present invention having the above-mentioned structure is subjected to a smoothing treatment of the printing surface by means such as polishing and rolling as necessary as in the conventional case. After that, the liquid crystal color display is finished through the steps of disposing electrodes and enclosing the liquid crystal.

By the way, since the present invention is not limited to the above-mentioned embodiments, various modifications can be made in accordance with the spirit of the claims.

For example, the substrate 1 is a ferritic stainless steel other than SUS430, that is, SUS405 / SUS.
429 / SUS430F / SUS434 or the like, or martensite stainless steel such as SUS403 / SUS410 / SUS630.

[0023]

As described above, according to the present invention, the etching stop made of nickel or nickel alloy formed by electrolytic plating on one surface of a ferritic or martensitic stainless steel sheet having a surface average roughness of 0.02 μmRa or less. Through the layer, a copper plating layer for forming groove-shaped ink cells is provided, and since the surface is an intaglio plate coated with hard chrome plating, plate making without surface defects can be easily performed,
A printed matter having an excellent print shape can be obtained.

Further, the linear expansion coefficient of the substrate is 1 as compared with the conventional intaglio plate.
Since it is as small as 0%, it is possible to perform printing with high alignment accuracy and to manufacture a color filter having a larger area.
In addition, since the structure eliminates the ballad copper plating layer required in the conventional intaglio plate, the plate making process is simplified and
It is possible to measure the film thickness of copper plating with an eddy current meter, which is inexpensive and easy to operate, which eliminates the inconvenience of finding defective depth of ink cells after plate making. Further, it has a remarkable effect that it is easy to store because it has a structure that is difficult to rust.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of an example.

FIG. 2 is an explanatory diagram of a conventional technique.

[Explanation of symbols]

 1 Substrate 2 Etching Stop Layer 3 Copper Plating Layer 4 Hard Chrome Plating 5 Ink Cell 6 Ballad Copper Plating Layer

Claims (1)

[Claims] 1. A groove-shaped ink cell formed on one surface of a ferritic or martensitic stainless steel sheet having a surface average roughness of 0.02 μmRa or less, with an etching stopper layer made of nickel or nickel alloy formed by an electrolytic plating method interposed therebetween. An intaglio printing plate, comprising a copper plating layer for forming a film, the surface of which is coated with hard chrome plating.