JPH06340053A - Printing plate and printing method - Google Patents

Abstract

PURPOSE:To eliminate the pinhole like defect in an ink pattern formed by printing, to make film thickness sufficient, to make a surface smooth and to enhance etching resistance by forming the bottom surface of an ink receiving part from a silicone resin. CONSTITUTION:The silicone resin 3 becoming the bottom surface of an ink receiving part 10 is arranged by a method wherein hydrophilizing treatment is applied to the exposed part 1a of an alumnum substrate 1 not coated with a photosensitive resin 2 and an uncured silicone resin 3a compounded with a curing agent is uniformly applied to the surface of a roll 4 and this roll 4 is pressed to the moistened photosensitive resin 2 on the substrate 1 under rotation to form an uncured silicone resin layer 3b only on the surface of the photosensltive resin 2. The uncured silicone resin layer 3b is polymerized by heating to obtain a printing plate P1. The printing plate P1 is wetted with water and ink is applied to the moistened printing plate at a speed of 100mm/sec or less and transferred to perform printing.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a technique for printing and forming a fine pattern, and more specifically, for forming an electric circuit or the like on a printed wiring board, a TFT substrate, an IC substrate, etc. by an etching method. The present invention relates to a printing plate and a printing method for creating a fine resist pattern and the like.

[0002]

2. Description of the Related Art As a technique of this kind, an offset printing method using a planographic printing plate or a relief printing plate has already been industrialized. Since the electric circuit must not have defects such as disconnection and short circuit, the resist pattern used for forming the electric circuit is required to have high accuracy in width and thickness. For those requiring high resolution, for example, a presensitized plate (hereinafter referred to as PS plate) in which a photosensitive resin is applied to a surface of a grained aluminum substrate and dried, is used. Further, when it is required to print the ink pattern formed by printing without defects such as pinholes, the resin relief printing plate is used.

As a printing plate using the PS plate, as shown in FIG. 9, a photosensitive resin 2 is exposed and developed in a desired pattern on one surface of an aluminum substrate 1 to leave it, and a printing plate P4 is formed. There is something I did. In this type of printing plate, the exposed portion 1a of the aluminum substrate 1 becomes hydrophilic, and the photosensitive resin 2 left in a pattern form serves as an oleophilic ink receiving portion 10 to function as a printing plate.

That is, when a required ink (not shown) is inked on the printing plate P4 moistened with water, the ink does not ride on the water-exposed exposed portion 1a of the aluminum substrate 1,
Since a relatively thin film is formed only on the photosensitive resin 2, a desired ink pattern is formed by printing by transferring this to a material to be printed (not shown). When the ink on the resin 2 is transferred in a fluid state, the ink and the photosensitive resin 2 have a high affinity and the ink film splits on the way, so the total amount of the ink on the plate is covered. It cannot be transferred to the side of the printed matter.

Therefore, even if the ink film on the printing plate has no defects such as pinholes, the ink pattern transferred to the printing object has numerous pinhole-shaped defects, or the surface is uneven and the ink is uneven. Since the film thickness is thin, there is a problem that the etching resistance is lowered.

As a preventive measure against the above-mentioned defects, there is a method of thickening the ink film by performing printing 2 to 5 times instead of once, but even in this case, the surface of the ink pattern is smoothed. However, the etching resistance of the recessed portion is still low, and the occurrence of pinhole defects has not been completely prevented.

In this method of increasing the number of printings, attention should be paid to the fact that the raised portion of the ink pattern is crushed by the pressure at the time of transfer, so that it is likely to cause a defect that the etching pattern is thickened by protruding from the preset pattern size. is necessary.

On the other hand, when the cohesive force of the ink on the plate is increased to such an extent that the ink film does not split, this time the ink having a high affinity and the plate are firmly adhered, and the ink is transferred from the printing plate to the side of the printing object. It has the drawback that it cannot be transferred to.

Further, as shown in FIG. 10, by disposing the silicone resin 3 on the photosensitive resin 2 as a non-image area, it is possible to prevent water from being used in lithographic printing. P5 manufactured by KK etc. is also well known. In this printing plate P5, the surface of the silicone resin 3 serves as an ink repulsion (anti-adhesion) layer, and the exposed portion 2 of the photosensitive resin 2 that appears after the silicone resin 3 has been removed by development.
a serves as the lipophilic ink receiving portion 10 and functions as a printing plate.

A technique for printing a resist pattern on a printed wiring board by using this printing plate P5 and etching a copper foil with the obtained resist pattern is disclosed in Japanese Patent Laid-Open No.
No. 0-208484.

However, this printing plate P5 also has the same drawbacks as the printing plate P4.

Further, as illustrated in FIG. 11, a resist pattern is formed using a letterpress type printing plate P6 in which the photosensitive resin 2 is left in a pattern on the substrate, and a printed wiring board or the like is processed. Things are also being done.

Also in the printing using the printing plate P6, a large number of printings are formed or the resist pattern is formed thick or hard so that defects such as pinholes do not occur in the resist pattern transferred to the printing object. Measures to increase the etching resistance of the resist pattern have been taken, and as a method of responding to the demand to increase the transfer rate of ink from the plate to the printed material, the technique of curing the ink on the plate by drying or UV irradiation is For example, it is disclosed in JP-A-55-43919.

However, this relief printing plate P6 also had the same problems as those of the above-mentioned planographic printing plates P4 and P5.

[0015]

Therefore, there has been a strong expectation for the development of a printing technique capable of easily forming a fine pattern having no pinhole-like defects or unevenness on the surface.

[0016]

The present invention has been made to solve the above-mentioned problems of the prior art, and a printing plate characterized in that the bottom surface of the ink receiving portion is formed of a silicone resin,

A printing method is provided, which comprises inking a printing plate having a bottom surface of an ink receiving portion made of a silicone resin at a speed of 100 mm / sec or less, and then transferring and printing the ink. However, the problems of the above-mentioned conventional techniques are solved.

The bottom surface of the ink receiving portion in the present invention does not mean a concave portion on the external appearance of the printing plate, but the bottom portion of the ink receiving portion, that is, a flat portion, and therefore, the relief printing plate. Then, the raised surface becomes the bottom surface of the ink receiving portion.

[0019]

Since the ink is inked at a speed of 100 mm / sec or less, the ink can be reliably supplied to the ink receiving portion whose bottom surface is formed of the silicone resin having a low affinity with the ink. Since the ink thus supplied onto the printing plate is easily peeled off from the silicone resin and transferred to the side of the printing object, the ink pattern printed on the printing object may have pinhole-like defects. Or, since the film thickness is sufficient and the surface is smooth, the etching resistance is good.

[0020]

Embodiments of the present invention will now be described in more detail with reference to the drawings.

(Embodiment 1) A printing plate P1 according to a first embodiment shown in FIG. 1 has a thickness of 0.24 mm on an aluminum substrate 1 which is grained and electropolished. The photosensitive resin 2 having a width of about 2 μm is formed in a test pattern having a line width of 30 μm, and the affinity with the ink (not shown) is lower than the affinity with the photosensitive resin on the photosensitive resin 2. The silicone resin 3 has a thickness of about 5 μm, and the portion of the silicone resin 3 is a planographic plate that functions as the ink receiving portion 10.

The photosensitive resin 2 in the form of a test pattern provided on the aluminum substrate 1 is, for example, a commercially available PS plate coated with a photosensitive resin having a thickness of about 2 μm. It is formed by development processing.

In order to dispose the silicone resin 3 on the bottom surface of the ink receiving portion 10, first, the exposed portion 1a of the aluminum substrate 1 not covered with the photosensitive resin 2 is hydrophilized (for example, Fuji Photo Film Co., Ltd. ) EU-3, GU-
After applying 7 etc. to the surface, it is washed with water) and made wet with water. Then, as shown in FIG. 2, an uncured silicone resin (for example, TSE3450 manufactured by Toshiba Silicone Co., Ltd.) containing a curing agent is uniformly attached to the surface of the rubber roll 4 to a thickness of 5 μm. Is pressed against the photosensitive resin 2 of the plate moistened with water and rotated,
An uncured silicone resin layer 3b having a thickness of 5 μm is formed only on the surface of the photosensitive resin 2.

When this is heated and held at 130 ° C. for 3 hours, the uncured silicone resin layer 3b is polymerized to obtain the printing plate P1 having the above-mentioned structure.

After moistening the printing plate P1 with water, the printing plate P1 shown in FIG.
When the roll 5 to which the ink 6 for UV-curable offset printing is attached is rotated at a speed of, for example, 100 mm / sec and brought into contact with the surface of the printing plate P1, the ink 6 rolls the silicone resin 3 on the bottom surface. Ink receiving part 1
The ink layer 6a was transferred to the side of 0 and was formed with a smooth surface without defects such as pinholes, but the ink 6 was not transferred to the exposed portion 1a of the aluminum substrate 1 wet with water. .

When the ink layer 6a formed on the printing plate P1 is irradiated with ultraviolet rays, the polymerization proceeds to increase the cohesive force of the ink, and the affinity between the ink layer 6a and the printing plate P1 is greatly exceeded. In this state, the printing surface of the printing plate P1 is pressed against a printing material (not shown) with a predetermined printing pressure, and when the two are separated, the ink layer 6a is peeled off from the printing plate P1 without splitting and the entire amount is covered. Transferred to the print side.

The ink pattern transferred from the printing plate P4 onto the printing material in this manner has no pinhole-like defects, has a sufficient thickness, and has a smooth surface. The etching property was extremely good.

Further, when the oxidation polymerization type offset printing ink is supplied to the printing plate P1 by using the roll 5 and the plate surface is exposed to warm air of 180 ° C. for about 30 seconds, the progress of polymerization and the ink Due to the volatilization of the solvent therein, the cohesive force of the ink greatly exceeded the affinity between the plate and the ink. Therefore, in this case as well, the ink on the plate was completely peeled off from the plate without being split, and was transferred to the side of the material to be printed without causing defects.

(Embodiment 2) A printing plate P2 according to a second embodiment shown in FIG. 4 has a structure in which a silicone resin 3 is formed in a desired test pattern on one surface of an aluminum substrate 1. The exposed portion 1a of the aluminum substrate 1 surrounded by the silicone resin 3 is
It is a lithographic plate that functions as 0.

A method of manufacturing the printing plate P2 will be described with reference to FIG. First, a photosensitive resin such as a positive photoresist (AZLP-10 manufactured by Hoechst Japan Ltd .; not shown) is formed on one side of the aluminum substrate 1 having the above structure.
It is applied to a thickness of 0 μm, and based on this, a desired pattern is left and formed by the unexposed portion 2A of the photoresist by using a conventionally known exposure and development method.

Then, the unexposed portion 2A of the remaining photoresist is irradiated with ultraviolet rays, and an uncured silicone resin (for example, TSE345 manufactured by Toshiba Silicone Co., Ltd.) containing a curing agent is applied to the photoresist 2B thus exposed.
0) 3a is raised, and doctoring is performed along the surface of the photoresist 2B to remove the surplus portion of the silicone resin 3a which is raised higher than the photoresist 2B.

Subsequently, 1 part of a photoresist developing solution and 1 part of water
Immerse in a solution (not shown) consisting of 0 parts for about 30 seconds,
The uncured silicone resin 3a adhering to the surface of the photoresist 2B is removed. And after washing with water,
By allowing the silicone resin 3a to stand still until it cures, and finally removing the photoresist 2B by dissolution with a developing solution, a printing plate P2 having the configuration shown in FIG. 4 is obtained.

Also in this printing plate P2, the printing plate P
By inking in the same manner as in No. 1, the entire amount of the ink transferred on the plate was peeled off and transferred to the side of the material to be printed without splitting, and a defect-free ink pattern was formed.

(Embodiment 3) FIG. 6 shows the structure of a printing plate P3 according to a third embodiment. This printing plate P3 has, for example, a thickness of 0.
3 mm of photosensitive resin 2 is formed in a test pattern with a line width of 100 μm, and silicone resin 3 of 2 μm is formed on the surface.
The silicone resin 3 is disposed in a thickness of m and is a relief plate that functions as the ink receiving portion 10.

The test-patterned photosensitive resin 2 provided on the iron base 7 is formed by a conventionally known exposure and development process. Then, as shown in FIG. 7, an uncured silicone resin (for example, YR3365 manufactured by Toshiba Silicone Co., Ltd.) containing a curing agent is uniformly attached to the surface of the rubber roll 4 to a thickness of 2 μm. Is pressed against the surface of the plate and rolled several times to form an uncured silicone resin layer 3b on the surface of the photosensitive resin 2. When this is heated and held at 100 ° C. for 3 hours to cure the silicone resin layer 3b, the printing plate P having the structure shown in FIG.
3 is obtained.

On the printing plate P3, as shown in FIG.
When the roll 5 to which the ink 6 for UV-curing type offset printing is attached is rotated at a speed of 100 mm / sec and brought into contact with the printing plate P3, the ink 6 is transferred to the ink receiving portion 10 having the silicone resin 3 as the bottom surface. Then, the ink layer 6a was formed, but since the surface of the roll 6 did not contact the exposed portion 7a of the iron base material 7, there was no transfer of the ink 6 to this portion.

Ink layer 6a formed on this printing plate P3
When ultraviolet rays are radiated on the ink, the polymerization proceeds and the cohesive force of the ink is strengthened as in the case of the first embodiment. Therefore, the ink does not split even when it is transferred to the printing material, and the entire amount is peeled off from the printing plate. , Was transferred to the printing material in a defect-free state. Also, in the case of the oxidation polymerization type ink, printing was performed in a good state as in Example 1.

Since the present invention is not limited to the above-mentioned embodiments, appropriate modifications can be made in accordance with the spirit of the claims.

For example, the silicone resin 3 can be provided not only on the bottom surface of the ink receiving portion 10 but also on the side surface thereof so that the ink is more easily transferred to the printed material side.

[0040]

As described above, according to the present invention, it is possible to easily form a fine resist pattern having no defects such as pinholes on a printed wiring board / TFT board / IC board by a printing method. Therefore, it has a remarkable effect in a manufacturing process of forming an electric circuit or the like by an etching method.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of a printing plate used in Example 1.

FIG. 2 is an explanatory view of a method for manufacturing the printing plate used in Example 1.

FIG. 3 is an explanatory diagram of a printing method according to the first embodiment.

FIG. 4 is an explanatory diagram of a printing plate used in Example 2.

FIG. 5 is an explanatory diagram of a method for manufacturing the printing plate used in Example 2.

FIG. 6 is an explanatory diagram of a printing plate used in Example 3.

FIG. 7 is an explanatory diagram of a method for manufacturing the printing plate used in Example 3.

FIG. 8 is an explanatory diagram of a printing method according to a third embodiment.

FIG. 9 is an explanatory diagram of a conventional printing plate.

FIG. 10 is an explanatory view of another conventional printing plate.

FIG. 11 is an explanatory view of another conventional printing plate.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Aluminum substrate 1a Exposed part 10 Ink receiving part 2 Photosensitive resin 2a Exposed part 2A Photoresist (unexposed part) 2B Photoresist (exposed part) 3 Silicone resin 3a Silicone resin (uncured) 3b Silicone resin layer 4/5 roll 6 Ink 6a Ink layer 7 Iron substrate 7a Exposed part P1, P2, P3, P4, P5, P6 Printing plate

Claims (2)

[Claims] 1. A printing plate comprising a bottom surface of an ink receiving portion made of a silicone resin. 2. A printing method comprising inking a printing plate having a bottom surface of an ink receiving portion made of a silicone resin at a speed of 100 mm / sec or less, and then transferring the ink for printing.