JPH1035129A - Printing intaglio and its manufacture - Google Patents

Abstract

PROBLEM TO BE SOLVED: To form an ink layer of arc sectional shape at all times regardless of the line width and the like by forming the bottom face of a recessed section formed on a printing plate to be less deep on end section of the recessed section and deep on a central section. SOLUTION: One intermediate step section 37b having the depth D2 deeper than the depth D1 of an end section 31a and less deep than the depth D3 of a central section 31c is formed between the end section 31a and the central section 31c of a recessed section 3. As the depth D1 of the end section 31a of the recessed section 3 is less deep than the depth D3 of the central section 31c, an ink layer formed on a transparent base by filling ink by using a doctor blade or the like into the recessed section 3 and transferring the ink through a blanket or the like is almost flat with the arch sectional shape at all times regardless of the line width and the like.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printing intaglio used for intaglio printing such as intaglio offset printing.

[0002]

2. Description of the Related Art A color filter used in a liquid crystal display for full-color display includes three transparent colored layers of red (R), green (G), and blue (B), and these transparent colored layers are separated for each pixel. A light shielding layer called a black matrix is formed on a transparent substrate, and it is necessary to form a fine pattern with high accuracy. Therefore, conventionally, it has been mainly manufactured by a so-called photolithography method.

However, recently, the demand for liquid crystal displays for full-color display has increased dramatically, and it has become necessary to produce color filters simply and in large quantities. To deal with this, concave portions corresponding to print patterns have been formed. The use of a so-called intaglio offset printing method of transferring the ink filled in the indentations of the intaglio to the surface of a printing substrate (in this case, a transparent substrate) via a blanket made of a flexible material such as rubber has been studied. I have.

In the above-described intaglio offset printing method, there is an advantage that high-precision printing can be performed as compared with other printing methods by forming the intaglio by the above-described photolithography method or the like. Further, the intaglio offset printing method is superior to other printing methods (for example, a waterless flat plate offset printing method) in terms of linearity of a printing line and uniformity of an ink film thickness.

Further, since the depth of the concave portion of the intaglio plate, which is filled with ink, is large, the thickness of the ink layer necessary for the light-shielding layer can be obtained by one printing, or the depth of the concave portion is adjusted. This allows the thickness of the ink layer to be freely adjusted, which is also an advantage of the intaglio offset printing method. The above-mentioned color filter is required to be flat because it is formed on the surface of one of a pair of transparent substrates sandwiching the liquid crystal layer, which constitutes the liquid crystal display, on the liquid crystal layer side.

For this reason, conventionally, a flattening layer is further formed on the four types of ink layers of the three colors R, G and B and the light-shielding layer which are transferred onto a transparent substrate by the intaglio offset printing method. Recently, attempts have been made to omit the flattening layer in order to improve the light transmittance of the color filter and further reduce the cost. Alternatively, a liquid crystal display using a ferroelectric liquid crystal, which requires a flatter color filter than ever before, has been put into practical use.

To cope with these movements, the ink layer transferred onto the transparent substrate by the intaglio offset printing method is cured several times to ten and several times by a roller made of a material having low affinity for the ink before curing. Attempts have been made to flatten by crushing to a certain extent. Since the above-described flattening process is performed on the ink layer before curing as described above, in order to suppress a decrease in the yield of the color filter due to adhesion of dust or the like, the number of times the ink layer is crushed by the roller is It is desirable to minimize it.

In other words, it is preferable that the ink layer is easily flattened with a smaller number of squashings. For this purpose, for example, as shown in FIG. Previous studies have shown that it is ideal that the cross-sectional shape of the mountain is substantially flat itself.

[0009]

However, as shown in FIG. 4 (b), the ink layer 6 transferred onto the transparent substrate 5 by the intaglio offset printing method using a conventional intaglio has a substantially sectional shape. It has become apparent that there is a problem that the shape becomes concave, and the number of times of crushing required for flattening increases, or that flattening cannot be performed sufficiently even if it is pressed many times.

The reason why the ink layer 6 has a substantially concave cross-sectional shape is that when the ink is transferred from the intaglio to the blanket, as shown by a dashed line in FIG.
Is pressed into the concave portion 91 of the intaglio plate 9, whereby the ink layer at the end portion of the concave portion 9 l becomes thicker and the ink layer at the central portion becomes thinner. It is considered that the main cause is that the distribution of the ink is varied between the end portion and the center portion of the ink layer transferred to the blanket 7 as a result of accumulation on both sides of the blanket 7.

The above-mentioned phenomenon tends to be remarkable especially when the width of the concave portion 91 of the intaglio 9 is large. SUMMARY OF THE INVENTION An object of the present invention is to provide a novel intaglio for printing, which can always form an ink layer having a mountain-shaped cross section irrespective of a line width or the like, and a method of manufacturing the same.

[0012]

According to the present invention, there is provided an intaglio printing plate according to the present invention, wherein a bottom surface of a concave portion formed on the plate surface is shallow at an end portion of the concave portion and deep at a central portion. It is characterized by being formed in.
In the printing intaglio of the present invention having the above configuration,
As described above, since the bottom surface of the concave portion is formed to be shallow at the end portion of the concave portion and the central portion is formed deep, for example, even in the case of the concave portion corresponding to the ink layer having a wide line width, the press-fitting of the blanket causes the depression. The ink layer at the end of the concave portion does not become extremely thicker than the ink layer at the center. Not only that, by setting the ratio between the depth of the end portion and the center portion of the concave portion, the ink layer at the end portion of the concave portion and the ink layer at the center portion have the same thickness, or the ink portion at the end portion has the same thickness. The layer may be thinner than the central ink layer. This prevents the ink layer transferred on the blanket from having a variation in the ink distribution between the end portion and the central portion, thereby preventing the ink layer formed on the transparent substrate from having a substantially concave cross-sectional shape. And the ink layer is
For example, regardless of the line width and the like, it always has a mountain-shaped cross-sectional shape, and can be easily flattened with a smaller number of times of crushing.

Further, the method for manufacturing an intaglio printing for printing according to the present invention for manufacturing the intaglio printing for printing according to the present invention includes a method for manufacturing an intaglio printing for printing, the method comprising: Is formed, the step of forming a narrower concave portion on the bottom surface of the concave portion is performed once or 2 times.
By performing the process more than once, the bottom surface of the concave portion corresponding to the print pattern is formed to be shallow at the end portion of the concave portion and deep at the center portion.

According to the manufacturing method of the present invention, the printing intaglio of the present invention, which has the excellent effects as described above, can be easily and simply formed by a combination of conventional techniques such as formation of a resist film and etching. It becomes possible to manufacture efficiently.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION
This will be described with reference to the drawings showing an example of the state. See Figure 1
As described above, the intaglio 1 for printing in this example is formed on the plate surface 2.
Of the bottom surface 31 of the concave portion 3 corresponding to the printing pattern,
Depth D of end 31a of recess 3 ₁But the central part 31
c depth D_ThreeThe bottom surface 31 so that it is shallower than
It is stepped.

In the case of the example shown in the figure, the depth D ₂ is located between the end portion 3la and the central portion 31c.
Deeper than the depth D ₁ of the 1a, and the depth D of the central portion 31c
An intermediate step portion 31b of 1 level shallower than ₃ is formed.
According to the printing intaglio 1 of the above example, as described above, the recess 3
Depth D ₁ of the end portion 31a is, the depth D of the central portion 31c
_Since it is shallower than 3, the ink is filled into the concave portion 3 using a doctor blade or the like, and the ink is transferred via a blanket or the like, and the ink layer 6 formed on the transparent substrate 5 becomes, for example, As shown in FIG. 4 (a), regardless of the line width or the like, it always has a mountain-shaped cross-sectional shape and is substantially flat itself.

Accordingly, such an ink layer is, for example, shown in FIG.
(b) Compared to those having a substantially concave cross-sectional shape as shown in (b), since the number of times of crushing by a roller for flattening can be reduced, the reduction in yield due to adhesion of dust and the like is suppressed, and a color filter is formed. Etc. can be manufactured efficiently and with high productivity. In the example of the figure,
As described above, the end portion 31a and the central portion 31c of the concave portion 3 are formed.
And one intermediate step 3 having an intermediate depth between the two.
Although lb is provided, the intermediate step 31b may be omitted, or two or more steps may be provided.

Further, for example, in the case of a print pattern in which a wide portion and a narrow portion are mixed, the number of steps on the bottom surface of each concave portion, the width of each step, and the like are adjusted, or the line width is wide. The configuration of the present invention can be adopted only on the bottom surface of the concave portion corresponding to the portion. Further, in the example of the figure, the bottom surface 31 of the concave portion 3 is stepped as described above in order to make the depth between the end portion 31a and the central portion 31c of the concave portion 3 as described above. The same effect may be obtained as a curved surface or a V-shaped slope.

Various materials used for the intaglio, such as metal and glass, can be used as they are as the base material of the intaglio 1 for printing. Intaglio 1 for printing in the example of the above figure
2 (a) to 2 (c), 3 (a) to 3 (a)
The manufacturing method of the present invention shown in (c) is suitably employed. That is, first, as shown in FIG.
A resist film 41 corresponding to the print pattern is formed on the surface 2a serving as the plate surface 2 of the substrate la to be used.

Next, when the surface 2a of the substrate 1a is etched, a concave portion 3a corresponding to the print pattern corresponding to the shape of the resist film 41 is formed (FIG. 2 (b)).
The depth d ₁ of the concave portion 3a is the depth D ₁ of the portion 3la end of the recess 3 described above. Next, as shown in FIG. 2C, the surface 2a of the substrate 1a from which the previous resist film 41 has been removed.
Then, a resist film 42 corresponding to a pattern for forming a narrower concave portion is formed on the side surface and the bottom surface of the concave portion 3a and on the bottom surface of the concave portion 3a, and is etched.

Then, as shown in FIG.
The concave portion corresponding to the shape of the resist film 42
A concave portion 3b narrower than the bottom surface of the portion 3a is formed. This
Depth d of the concave portion 3b_TwoIs the depth d of the recess 3a.₁With
Total depth d₁+ D _TwoIs the intermediate step 3 of the recess 3 described above.
lb depth D_TwoSet to equal.

Next, on the surface 2a of the substrate 1a from which the resist film 42 has been removed, and on the side and bottom surfaces of the concave portions 3a and 3b, and on the bottom surface of the concave portion 3b, a concave portion having a smaller width than that is formed. A resist film 43 corresponding to the pattern is formed (FIG. 3B). After etching, Fig. 3 (c)
As shown in FIG. 1, a concave portion 3c having a width smaller than the bottom surface of the concave portion 3b is formed on the bottom surface of the concave portion 3b in accordance with the shape of the resist film 43. Thereafter, when the resist film 43 is removed, the printing shown in FIG. Is completed.

The depth d ₃ of the recess 3c is the total depth d ₁ + d ₂ of the depths d ₁ and d ₂ of the recesses 3a and 3b.
+ D ₃ is set to be equal to the depth D ₃ of the central portion 31c of the concave portion 3 described above. According to the manufacturing method of the present invention described above, there is an advantage that the intaglio printing plate of the present invention, which has the above-described excellent effects, can be manufactured by a combination of conventional techniques such as formation of a resist film and etching.

Each of the resist films 41 to 43 is formed by a so-called photolithography method in which a photosensitive resist agent is applied on a substrate la, dried, a printed pattern original plate is exposed, developed, and developed. This is preferable in terms of the above-described accuracy, reproducibility, mass productivity, and the like. However, a photosensitive resist agent is applied on the substrate 1a, dried, and then directly exposed by scanning with a laser beam or the like, for example, by another technique parallel to the photolithography method. 43 may be formed. Alternatively, a concave portion may be formed directly on the substrate 1a by scanning with a processing laser beam or the like without depending on the resist film and the etching.

In addition, various changes can be made without departing from the spirit of the present invention.

[0026]

The present invention will be described below with reference to examples and comparative examples. Example 1 A positive photosensitive resist was applied to the surface of a substrate la made of soda lime glass and dried, and then a line width of 110 μm was obtained.
An original plate having a m-shaped striped print pattern was overlapped, exposed, and developed to form a resist film 41 corresponding to the print pattern [FIG. 2 (a)].

Next, the substrate 1a is maintained at a constant temperature.
Immersed in an etching solution for glass
And a kneading width of 110 μm and a depth of
D ₁= 8 μm stripe-shaped recess 3a at the first stage
It was formed [FIG. 2 (b)]. Next, from the surface of the substrate 1a,
After removing the resist film 4l of the above, in the same process as above,
In the center of the bottom surface of the first-stage concave portion 3a, a line width of 50 μm
A resist film 42 for forming a concave portion is formed.
Ching, line width 50μm, depth d_Two= Second stage of 4 μm
An eye recess 3b was formed [FIGS. 2 (c) to 3 (a)].

Next, after the resist film 42 is again removed from the surface of the substrate la, a recess having a line width of 20 μm is formed at the center of the bottom surface of the second recess 3b in the same process as described above. The resist film 43 was formed and etched to form a _third -stage concave portion 3c having a line width of 20 μm and a depth d ₃ = 4 μm [FIGS. 3 (b) to 3 (c)]. The resist film 43 is removed, a recess 3 which bottom 3l becomes 3-step staircase shape as shown in FIG. L, and depth D ₁ = 8 [mu] m portion 3la end of the recess 3, an intermediate The intaglio printing plate 1 in which the depth D ₂ of the step portion 3lb was 12 μm and the depth D ₃ of the central portion 31c was 16 μm was manufactured.

Each of the original plates of the printing pattern used in the above-mentioned three etchings was a film having a thickness of 0.1 μm sputter-deposited on the surface of a soda-lime glass substrate.
The chromium film of m was used by removing only a portion corresponding to the print pattern by laser light irradiation. The intaglio printing plate was set in an intaglio offset printing press using a blanket whose surface layer was made of silicone rubber,
Ink was printed on the transparent substrate under the conditions of a transfer speed of 10 mm / sec between the blanket and a transfer speed of 300 mm / sec between the blanket and the transparent substrate. The printing pressure was set so that the blanket nip amount was 8 mm. As the ink, a steady flow viscosity of 10 in which a pigment was finely dispersed in a polyester resin base to an average particle size of about 0.05 μm was used.
One having a poise of 00 and a yield value of 10,000 dyn / cm was used.

After the ink layer is cured,
When the cross-sectional shape was observed with a microscope, it was confirmed that the cross-sectional shape was a mountain shape as shown in FIG. The level difference on the surface of the ink layer was measured using a surface profiler [P-10 manufactured by Tencor Co., Ltd.].
It was 5 μm. Further, the ink layer before curing was crushed only once by a roller, then cured, and the level difference of the ink layer surface was measured in the same manner as above.
It was confirmed that the surface could be flattened to μm.

COMPARATIVE EXAMPLE 1 In the same process as in Example 1, a soda lime glass substrate was provided with a stripe-shaped recess having a line width of 110 μm and a depth of 10 μm and having only one step. Intaglio for printing. Using the intaglio printing plate, an ink layer was formed and cured in the same manner as in Example 1, and the cross-sectional shape was observed with a microscope. As a result, a substantially concave shape as shown in FIG. Was confirmed. Further, the level difference on the surface of the ink layer was measured using the above-mentioned surface shape measuring instrument and found to be ± 0.5 μm. Further, the ink layer before curing was crushed only once by a roller and then cured, and the level difference on the surface of the ink layer was measured in the same manner as described above. As a result, the ink layer could be flattened to only ± 0.2 μm.
Therefore, while increasing the number of times of crushing up to 15 times and increasing by 1 time, the level difference of the cured ink layer surface was measured.
Even if the squeezing is performed 15 times, the ink layer is ± 0.15μ.
m could be flattened.

[0032]

As described above in detail, according to the intaglio printing for printing of the present invention, an ink layer having a mountain-shaped cross section which can be easily flattened by crushing is always formed regardless of the line width and the like. Can be. Therefore, if the intaglio printing plate of the present invention is used, the number of times of crushing by the roller for flattening the ink layer can be reduced. It has a specific effect that it can be manufactured with productivity. Further, according to the method of manufacturing an intaglio printing plate of the present invention, it is possible to easily and efficiently manufacture the intaglio printing plate of the present invention having excellent characteristics as described above by a combination of the conventional techniques.

[Brief description of the drawings]

FIG. 1 is an enlarged sectional view showing an example of an embodiment of a printing intaglio according to the present invention.

2 (a) to 2 (c) are enlarged cross-sectional views showing steps of manufacturing the printing intaglio of FIG. 1;

3 (a) to 3 (c) are enlarged cross-sectional views showing steps of manufacturing the printing intaglio of FIG. 1;

FIGS. 4A and 4B are enlarged cross-sectional views each showing a cross-sectional shape of an ink layer formed on a substrate by an intaglio offset printing method.

FIG. 5 is an enlarged sectional view showing an example of a conventional printing intaglio.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Intaglio for printing 2 Plate surface 3 Depression 3l Bottom surface 3la Edge part 31c Central part la Substrate 2a Surface 3a, 3b, 3c Depression

Claims (2)

[Claims] An intaglio printing for intaglio printing, characterized in that the bottom surface of the recess formed in the plate surface is formed so as to be shallow at the end of the recess and deep at the center. For intaglio. 2. The method for producing an intaglio printing plate according to claim 1, wherein a concave portion corresponding to the printing pattern is formed on a surface of the substrate to be the intaglio plate, the surface being the plate surface of the intaglio plate. The step of forming a narrower concave portion on the bottom surface of the concave portion is performed once or two or more times so that the bottom surface of the concave portion corresponding to the print pattern has a shape that is shallow at the end portion of the concave portion and deep at the central portion. A method for producing an intaglio printing plate, comprising: