JP3433353B2 - Orientation material printing plate - Google Patents

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an alignment material printing plate used for transfer printing of an alignment material on an electrode formation surface of a liquid crystal element substrate.

[0002]

2. Description of the Related Art A liquid crystal element is one in which a liquid crystal is sandwiched between a pair of transparent substrates made of glass or the like, and transparent display electrodes are formed on the surfaces of the pair of substrates facing each other. At the same time, an alignment film for aligning liquid crystal molecules in a predetermined alignment state is provided thereon.

In this liquid crystal element, generally, a pair of substrates each having a display electrode and an alignment film formed thereon are joined together through a frame-shaped sealing material, and a region surrounded by the sealing material between the both substrates. Is filled with liquid crystal, and the alignment films provided on both substrates are formed in the regions surrounded by the sealing material.

The above-mentioned alignment film is formed by printing an alignment material made of polyimide or the like on the electrode formation surface of the substrate. Generally, the alignment material is printed on the surface of the alignment material supply body with a liquid alignment material. It is carried out by a transfer printing device which is applied in a thickness and transfers the alignment material onto a substrate by using a printing plate.

FIG. 9 is a side view showing an example of the transfer printing apparatus. FIG. 9A shows a state when an alignment material is being applied to the surface of the alignment material supply body, and FIG. 9B is a state where it is applied to the surface of the alignment material supply body. The state when the alignment material is attached to the printing plate, (c) shows the state where the alignment material is printed on the substrate.

This transfer printing apparatus uses a flat plate (hereinafter referred to as an orientation material supply plate) 2 whose surface is finished to be smooth as an orientation material supply body, and the orientation material supply plate 2 is horizontal. It is fixed on one end side of the base 1.

The upper surface of the base 1 on the other end side serves as a substrate mounting portion, and the liquid crystal element substrate 10 has the orientation material printing surface (electrode formation surface) facing upward. The substrate is placed on the substrate mounting part of (1), and the alignment material printing surface thereof is positioned and fixed so that it is flush with the top surface of the alignment material supply plate 2.

An orientation material printing roller 3 is horizontally provided above the base 1 in a state of being orthogonal to the length direction of the base 1, and the peripheral surface of the printing roller 3 is provided. An orienting material printing plate 4 is provided in.

The printing roller 3 has a roller driving mechanism (not shown) in which the orientation material printing plate 4 attached to the circumferential surface of the roller is very small with respect to the upper surface of the orientation material supply plate 2 and the orientation material printing surface of the substrate 10. It is supported so as to come into contact with the contact pressure, is rotated in both directions, and is moved laterally in the longitudinal direction of the base 1 in synchronization with the rotation.

The orientation material printing plate 4 provided on the circumferential surface of the printing roller 3 is made of a flexible resin sheet, and the orientation surface adhered to the printing surface (front surface) of the orientation material is applied to the printing surface. Minute protrusions for holding are provided at close intervals.

That is, FIG. 11 is a plan view of a conventional orientation material printing plate in a developed state, (a) is an overall view,
(B) is an enlarged view of a part of the printing plate. 12 is shown in FIG.
FIG. 9 is a sectional view taken along line XII-XII in FIG.

The orientation material printing plate 4 is a plate surface having a size (area) corresponding to the orientation material printing region of the substrate 10 and microprotrusions 4a of the same size provided at equal intervals over the entire area. The projection 5 has a cylindrical shape.
The diameter and height of the protrusions 5 are about 10 μm, and the distance between the protrusions 5 and 5 is about 10 μm.
It is supposed to be m.

Then, as shown in FIG. 9, the orienting material printing plate 4 is wound around almost half of the peripheral surface of the printing roller 3, and is adhered to the roller peripheral surface by a double-sided adhesive tape or the like.

A liquid crystal element substrate 1 formed by the above transfer printing apparatus.
The printing of the alignment material on 0 is performed as follows. First, as shown in FIG. 9A, an appropriate amount of liquid alignment material a is dropped on one end of the alignment material supply plate 2,
By uniformly spreading the orientation material a with a squeegee 6, the orientation material a is applied to the surface of the orientation material supply plate 2 to a constant thickness over an area equal to or larger than the plate surface of the orientation material printing plate 4. To do.

Next, as shown in FIG. 9B, while rotating the alignment material printing roller 3 in the direction of the solid line arrow, the alignment material printing roller 3 is moved laterally in the direction of the broken line arrow in synchronization with the rotation. The orientation material a on the surface of the orientation material supply plate 2 is attached to the plate surface of the orientation material printing plate 4 on the peripheral surface.

In this case, the alignment material a enters the portion between the projections 5 and 5 on the plate surface of the alignment material printing plate 4 as shown by the two-dot chain line in FIG. Held by In addition, each projection 5 on the plate surface of the alignment material printing plate 4
Since they have the same size and are provided at equal intervals over the entire plate surface, the amount of the alignment material attached to the plate surface per unit area is uniform over the entire plate surface.

Thereafter, as shown in FIG. 9 (c), the orientation material printing roller 3 is rotated in the direction of the solid arrow opposite to the above, and is moved laterally in the direction of the broken arrow in synchronization with the rotation. Then, the alignment material a attached to the plate surface of the alignment material printing plate 4 is printed on the electrode formation surface of the liquid crystal element substrate 10.
When printing the alignment material a on the substrate 10, the alignment material a attached to the plate surface of the alignment material printing plate 4 is printed on the substrate 10.
The substrate 1 so that the alignment material printing area of the substrate 1 is correctly printed.
It is performed with 0 positioned.

FIG. 10 is an enlarged sectional view showing the X portion in FIG. 9C, in which the orientation material a attached to the plate surface of the orientation material printing plate 4 is rotated by the orientation material printing roller 3. Further, the printing is performed on the electrode formation surface of the substrate 10 along with the lateral movement. The substrate 10 is used, for example, in a simple matrix type liquid crystal device, and the electrodes 11 on the substrate 10 are scanning electrodes or signal electrodes.

In this case, since the alignment material a adheres to the plate surface of the alignment material printing plate 4 thickly between the projections 5 and 5 and extremely thinly on the projections 5, The printed thickness of the alignment material a on 10 is thin in the portion corresponding to the protrusion 5 and thick in other portions, but the alignment material a is liquid,
Since the flow from the thickly raised portion to the thin portion flows, the alignment material a printed on the substrate 10 becomes a film having a uniform thickness as shown on the left side of FIG.

The alignment film is formed by baking the film of the alignment material a printed on the substrate 10, and then subjected to the alignment treatment by rubbing. Further, the liquid crystal element is configured such that a pair of substrates each having an alignment film formed on the electrode formation surface are bonded together via a frame-shaped seal material surrounding the alignment film formation region and surrounded by the seal material between both substrates. It is manufactured by filling the liquid crystal in the filled area.

The transfer printing apparatus described above uses a flat plate-shaped orientation material supply plate 2 as the orientation material supply body, but a roller is used as the orientation material supply body in the orientation material transfer printing apparatus. In the transfer printing device, an alignment material is applied to the peripheral surface of the alignment material supply roller with an alignment material application roller to a certain thickness, and the alignment material is printed using the alignment material printing plate described above. Transfer printing is performed on the liquid crystal element substrate by rollers.

[0022]

By the way, in the above-mentioned conventional orientation material printing plate 4, as shown in FIGS. 11 and 12, projections 5 of the same size are provided at equal intervals over the entire area of the plate surface. Therefore, the adhesion amount per unit area of the orientation material a applied to the orientation material supply plate 2 or the orientation material supply body roller such as the orientation material supply body roller shown in FIG. Is uniform over the entire printing surface,
Therefore, the printing amount of the alignment material a printed on the substrate 10 per unit area is substantially uniform over the entire printing area of the alignment material of the substrate 10.

However, in the transfer printing of the alignment material using the alignment material printing plate 4, there is a problem that the thickness of the peripheral edge portion of the alignment film formed on the substrate becomes larger than the desired thickness. .

This is because when the liquid alignment material a is printed on the substrate 10, the peripheral edge of the printed film of the alignment material a rises due to surface tension. FIG. 13 is a cross-sectional view of the vicinity of an end portion of an alignment material film printed on a substrate 10 using a conventional alignment material printing plate 4, and the film of the alignment material a has a peripheral edge portion due to surface tension. Thus, the film thickness of the peripheral portion of the alignment film formed by firing this alignment material film becomes thicker than the desired film thickness.

If the alignment film formed on the substrate is a film having a thick peripheral edge as described above, the liquid crystal layer thickness of the manufactured liquid crystal element (the distance between the alignment film surfaces of the pair of substrates is increased). )
Is smaller in the portion corresponding to the peripheral portion of the alignment film, that is, in the peripheral portion of the display region, and therefore Δn · d (refractive index anisotropy Δn of liquid crystal and liquid crystal layer thickness d The value of (product) and becomes small in the peripheral portion of the display area, and the electro-optical characteristics of this peripheral portion deteriorate, causing display unevenness.

Since the alignment film is formed on both substrates of the liquid crystal device, the liquid crystal layer thickness at the peripheral portion of the display region is one of the alignments as compared with the liquid crystal layer thickness at the central portion of the display region. It is reduced by about twice the difference in film thickness between the peripheral portion and the central portion of the film.

An object of the present invention is to provide an alignment material printing plate capable of forming an alignment film on a liquid crystal device substrate, the film thickness of the peripheral portion of which is almost the same as the desired film thickness. Is.

[0028]

In the printing plate for an alignment material of the present invention, a liquid alignment material applied to an alignment material supply surface with a constant thickness is transferred and printed on an electrode forming surface of a substrate for a liquid crystal element. Which is used for, on the plate surface of the area corresponding to the alignment material printing area of the substrate, fine projections for holding the alignment material adhered to the plate surface are provided over the entire area at a dense interval, and The protrusions on the peripheral edge of the plate surface are provided at intervals smaller than the intervals of the protrusions on the central portion of the plate surface.

In this orientation material printing plate, the arrangement pitch of the protrusions at the peripheral portion of the plate surface may be the same as the arrangement pitch of the protrusions at the central portion of the plate surface. In this case, the diameter of the protrusions at the peripheral portion of the plate surface is It is made larger than the diameter of the protrusions in the central portion so that the protrusion interval at the peripheral portion of the plate surface is smaller than the protrusion interval at the central portion of the plate surface.

The orientation material printing plate of the present invention can also be used for printing an orientation material on a substrate on which color filters of a plurality of colors are formed with different film thicknesses. Around the area where the color filter is formed on the substrate, a dummy filter having substantially the same thickness as the thick color filter of the color filters of the plurality of colors is formed, and the plate surface of the alignment material printing plate is The peripheral portion with the reduced projection interval may have a size corresponding to the dummy filter formation portion of the substrate.

In this case, among the protrusions at the central portion of the plate surface of the alignment material printing plate, the protrusions at the portions corresponding to the thin color filters are larger than the intervals of the protrusions at the portions corresponding to the thick color filters. It is desirable to provide them at large intervals.

[0032]

In other words, the orientation material printing plate of the present invention is applied to the surface of the orientation material supply body with a constant thickness by providing the minute projections at the peripheral edge of the printing surface at intervals smaller than the spacing between the projections at the center of the printing surface. The amount of the alignment material adhered to the plate surface per unit area is reduced in the peripheral portion of the plate surface, and the alignment material enters the part between the projections on the plate surface and adheres to the plate surface. The smaller the distance between the protrusions, the smaller the amount of material adhered.

When the amount of adhesion of the alignment material printing plate per unit area to the plate surface is reduced in the peripheral portion of the plate surface in this way, the alignment material printing per unit area of the substrate is printed in the alignment material printing region. Although the amount is reduced in the peripheral portion of the alignment material printing region, this shortage of the printing amount is offset by rising of the peripheral portion of the film of the printed alignment material due to surface tension, and thus the alignment in that state. By firing the material film, it is possible to form an alignment film in which the film thickness of the peripheral portion is almost the same as the desired film thickness.

When the alignment material printing plate of the present invention is used for printing an alignment material on a substrate in which color filters of a plurality of colors are formed with different thicknesses, a color filter forming region on the substrate is used. A dummy filter having substantially the same thickness as the thicker color filter of the color filters of the plurality of colors is formed around the periphery of the plate, and the plate surface of the alignment material printing plate is provided with a peripheral portion with a small protrusion interval. Is a size corresponding to the dummy filter formation portion of the substrate, the film thickness of the peripheral portion is almost the same as the desired film thickness, and the film surface of the peripheral portion is a thick film surface on the color filter. It is possible to form an alignment film at the same level as the above.

Furthermore, in this case, among the protrusions at the central portion of the plate surface of the alignment material printing plate, the protrusions at the portions corresponding to the thin color filter are separated from the protrusions at the portions corresponding to the thick color filter. If you set it at a larger interval,
Since the orientation material is printed thick on the portion above the thin color filter, and the orientation material is printed thin on the portion above the thick color filter, on the color filter formation region of the substrate, An alignment film having a substantially flat film surface and having almost no step can be formed.

[0036]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment of the present invention will be described below with reference to FIGS. The alignment material printing plate of this example is used for printing an alignment material on a liquid crystal element substrate having extremely small irregularities on the surface on which the alignment film is formed.

FIG. 1 is a plan view of the orientation material printing plate in a developed state. (A) is an overall view, (b) is an enlarged view of a part of the central part of the plate surface, and (c) is a part of the peripheral part of the plate surface. FIG. 2 is a sectional view taken along line II-II of FIG. 1, and FIG. 3 is a sectional view taken along line III-III of FIG.

The alignment material printing plate 20 has a size (area) corresponding to the alignment material printing region of the liquid crystal element substrate.
Fine projections 21a and 21b for holding the alignment material a attached to the plate surface are provided at a close interval over the entire area, and the alignment material printing plate 20 is made of a flexible resin sheet. The projections 21a and 21b are integrally formed on the surface of the resin sheet.

The projections 21a and 21b are, for example, cylindrical, and the projections 21b on the peripheral edge portion 20b of the plate surface are provided with an interval s2 smaller than the interval s1 between the projections 21a on the central portion 20a of the plate surface. In FIG. 1A, the alternate long and short dash line indicates the boundary between the central portion 20a and the peripheral edge portion 20b of the printing plate.

In this embodiment, the plate surface peripheral portion 20b is
The arrangement pitch P2 of the protrusions 21b of the plate 21 is the same as the arrangement pitch P1 of the protrusions 21b of the plate surface central portion 20a (P1 = P2), and the diameter (diameter) r2 of the protrusions 21b of the plate surface peripheral portion 20b is set to the plate central portion 20a. Larger than the diameter r1 of the protrusion 21a,
The distance s2 between the protrusions 21b on the plate surface peripheral portion 20b is smaller than the distance s1 between the protrusions 21a on the plate surface central portion 20a.
However, the height h2 of the protrusion 21b of the plate edge portion 20b is
The same as the height h1 of the protrusion 21a of the central portion 20a of the printing plate (h1
= H2).

The alignment material printing plate 20 is used by being attached to the peripheral surface of the alignment material printing roller in the same manner as the conventional alignment material printing plate, and transfer printing of the alignment material onto the liquid crystal element substrate is performed. A liquid alignment material applied to the surface of the alignment material supply plate such as the alignment material supply plate or the alignment material supply roller is adhered to the plate surface of the alignment material printing plate 20 to form a plate surface of the alignment material printing plate 20. In FIG. 2 and FIG. 3, the alignment material a attached as indicated by the chain double-dashed line is printed in the alignment material printing area of the substrate.

In this case, the orienting material printing plate 20 has the protrusion 21b of the peripheral edge portion 20b of the plate surface, and the central portion 20a of the plate surface.
Since the protrusions 21a are provided with a spacing s2 smaller than the spacing s1, the amount of the alignment material applied to the plate surface per unit area on the plate surface is equal to the center portion of the plate surface. 20a is uniform over the entire area, but the amount of adhesion per unit area of the peripheral edge portion 20b of the plate surface is smaller than the amount of adhesion at the central portion 20a of the plate surface.

This is because the alignment material a enters and adheres to the plate surface of the printing plate 20 between the projections of the plate surface, and therefore the amount of the alignment material a adhered per unit area is large. Is smaller as the protrusion spacing is smaller.

The orientation material printing plate 20 has a smaller amount of adhesion per unit area to the printing plate surface at the peripheral portion 20b of the printing plate surface, so that the orientation material printing area of the substrate is aligned. The printing amount of the material a per unit area is reduced in the peripheral portion of the alignment material printing region, but the insufficient printing amount is offset by the rise of the peripheral portion of the printed film of the alignment material a due to surface tension. To be done.

That is, when the liquid alignment material a is printed on the substrate, the peripheral portion of the printed alignment material film rises due to surface tension, but the peripheral portion of this alignment material film is a portion where the printing amount of the alignment material a is small. Since this portion rises due to the surface tension, the film thickness of this peripheral portion is almost the same as the film thickness of the central portion of the alignment material film.

FIG. 4 is a cross-sectional view of an alignment material film printed on the substrate 10 using the alignment material printing plate 20 in the vicinity of an end portion thereof. The film of the alignment material a is substantially uniform over the entire area. It is a film thickness.

The substrate 10 shown in FIG. 4 is used, for example, in a simple matrix type liquid crystal element, and the display electrodes 11 on the substrate 10 are scanning electrodes or signal electrodes. The electrode 10 is formed on the upper surface of the substrate 10, that is, on the surface on which the alignment film is formed. However, since the thickness of the electrode 11 is extremely thin, the unevenness on the surface on which the alignment film is formed is extremely small, and therefore, The film surface of the alignment material film printed on the substrate 10 becomes substantially flat over the entire area.

The diameter r1 and height h1 of the protrusion 21a and the protrusion interval s1 of the plate surface central portion 20a of the alignment material printing plate 20 are necessary to form an alignment film having a predetermined thickness on the substrate 10. The protrusion 21b of the plate edge portion 20b has the same height h2 as the protrusion height h1 of the plate central portion 20a. The diameter r2 and the projection interval s2 may be set according to the diameter r1 and the projection interval s1 of the projection 21a of the plate surface central portion 20a.

As an example, for example, the diameter r1 and the height h1 of the protrusion 21a and the protrusion 21 of the central portion 20a of the plate surface are shown.
When the spacing s1 between the a and the 21a is r1 = 10 .mu.m h1 = 10 .mu.m s1 = 10 .mu.m, the diameter r2 of the projection 21b of the plate surface peripheral portion 20b is r2.
And the height h2 and the interval s2 between the protrusions 21b, 21b may be set to r2 = 15 .mu.m h2 = 10 .mu.m s2 = 5 .mu.m.

Further, the width w (see FIG. 1) of the peripheral edge portion 20b having a reduced projection distance on the plate surface is sufficient to be about 1 to 5 mm, and the peripheral edge portion 2 of the plate surface 2 extends over this width w.
If the protrusion interval of 0b is made small, the film thickness of the peripheral portion of the alignment material film printed on the substrate 10 becomes almost the same as the film thickness of the central portion of the alignment material film.

The alignment film is formed by firing the alignment material film printed on the substrate 10, and the alignment material film printed on the substrate 10 using the alignment material printing plate 20 is Since the film thickness is substantially uniform over the entire area, it is possible to form an alignment film in which the film thickness of the peripheral portion is almost the same as the desired film thickness.

The alignment film formed on the substrate 10 is
The alignment treatment is performed by rubbing the film surface in a predetermined direction. Since the film surface of the alignment film is almost flat over the entire area, the alignment treatment can be performed well.

Further, the alignment film formed on the substrate 10 is
If the film thickness of the peripheral part as described above is almost the same as the desired film thickness, the film surface of this film becomes almost flat over the entire alignment film. The (distance between the alignment film surfaces of the pair of substrates) is substantially the same over the entire display region, and therefore the value of Δn · d of the liquid crystal element is substantially uniform, so that a liquid crystal element with good display quality without display unevenness is obtained. Can be obtained.

Since the alignment film must be formed over at least the display region of the liquid crystal element, that is, the electrode formation region of the substrate 10, the plate surface of the alignment material printing plate 20 is the electrode formation region of the substrate 10. Although it is necessary to increase the area to some extent, the area of the plate surface may be such that the entire area of the peripheral edge portion 20b having a small protrusion interval corresponds to the outside of the electrode formation area of the substrate 10, or The portion 20b may have a size corresponding to the electrode forming region except for the outer edge portion thereof, and in any case, it is possible to form an alignment film in which the film thickness of the peripheral portion is almost the same as the desired film thickness. it can.

However, since the pair of substrates forming the liquid crystal element are bonded to each other through the frame-shaped sealing material surrounding the alignment film forming region, in order to reduce the size of these substrates, the substrates are moved outside the electrode forming region. It is desirable to minimize the protrusion width of the alignment film of 1.
As shown in FIG. 1A by enclosing the electrode forming area A of the substrate 10 by a chain double-dashed line, the peripheral area 20b of the plate surface is the electrode forming area A except for the outer edge thereof. It is preferable that the size corresponds to.

The orientation material printing plate 20 is not limited to a substrate having a surface on which an orientation film is formed with extremely small irregularities, and for example, a substrate having color filters of a plurality of colors formed in different thicknesses from each other. It can also be used for printing alignment materials.

FIG. 5 is a cross-sectional view in the vicinity of an end portion of an alignment material film printed by using the alignment material printing plate 20 on a substrate 12 in which color filters of a plurality of colors are formed with different thicknesses. is there.

The substrate 12 is used, for example, in a simple matrix type color liquid crystal element, and a transparent display electrode 13 is provided on the substrate 12 and a region where the electrode 13 is formed (liquid crystal element). Display area), and color filters of a plurality of colors, for example, red, green and blue color filters 14R, 14G,
14B are alternately arranged.

The display electrodes 13 formed on the substrate 12 are signal electrodes, and color filters 14R,
14G and 14B are formed in stripes corresponding to the respective signal electrodes 13.

Some simple matrix type color liquid crystal elements are provided with color filters on the substrate on which the scanning electrodes are formed. In that case, the color filters are made to correspond to the respective signal electrodes on the other substrate. Are formed in a stripe shape, and the scanning electrodes are formed so as to be orthogonal to the length direction of the color filter.

Then, the color filters 14 for the respective colors described above.
R, 14G, and 14B have their respective film thicknesses made different from each other and their light transmittances adjusted so that the liquid crystal elements can perform color display with good color balance.

These color filters 14R, 14G, 1
The respective film thicknesses of 4B are set depending on whether the color filter is provided above or below the electrode, and as shown in FIG.
In the substrate 13 provided with 14G and 14B, the film thickness of the color filters of each color is increased in the order of the red filter 14R, the green filter 14G, and the blue filter 14B.

Further, around the color filter forming area (the same area as the transparent electrode 13 forming area) on the substrate 12, the color filter forming areas are surrounded by the color filters 14R and 14G of the respective colors. , 14B, a dummy filter 15 having substantially the same thickness as the blue filter 14B having the largest film thickness is formed.

FIG. 6 is a perspective view of a part of the dummy filter 15 formed on the substrate 12 so as to surround the color filter forming region. The dummy filter 15 is made of silicon nitride (SiN) or the like as shown in the drawing. Of the insulating film, or is formed integrally with the blue filter 14B by the same filter material as the blue filter 14B.

The color filters 14R, 14
The G and 14B and the dummy filter 15 are covered with a transparent protective film (insulating film) 16 as shown in FIG.
3 is formed on the protective film 16.

The dummy filter 15 is formed to have substantially the same width as the width w of the plate surface peripheral portion 20b of the orientation material printing plate 20. That is, in the orientation material printing plate 20 for printing the orientation material a on the substrate 12, the peripheral surface 20 b of the printing plate 20 is such that the plate portion has a small protrusion interval.
The central portion 20a of the printing plate, which corresponds to the dummy filter forming portion and has a large protrusion interval, has a size corresponding to the color filter forming region of the substrate 12.

When the alignment material a is transferred and printed on the substrate 12 by using the alignment material printing plate 20, as described above, the printing of the alignment material a per unit area to be printed in the alignment material printing region of the substrate 12 is performed. The amount becomes smaller in the peripheral portion of the alignment material printing area, and this shortage of the printing amount is offset by the rise of the peripheral portion of the printed film of the alignment material a due to the surface tension, and thus the amount shown in FIG. As described above, the thickness of the peripheral edge portion of the alignment material film printed on the substrate 12 is almost the same as the thickness of the central portion, and the peripheral edge portion of the alignment material film is formed on the dummy filter 15 above. Because of this, the film surface of this peripheral portion is also at substantially the same level as the film surface of the portion on the blue filter 14B having a large film thickness.

Therefore, if the alignment material a is printed using the alignment material printing plate 20, the color filters 14R, 14R
On the substrate 12 on which G and 14B are provided, the film thickness of the peripheral portion is almost the same as the desired film thickness, and the film surface of the peripheral portion is the film surface of the portion on the blue filter 14B having a large film thickness. It is possible to form the alignment film at almost the same level.

The substrate 12 shown in FIG. 5 has color filters 14R, 14G and 14B for the respective colors formed in stripes, but the above-mentioned alignment material printing plate 20 includes color filters for the respective colors as liquid crystal elements. It can also be used for printing an alignment material on a substrate which is arranged in a mosaic pattern so as to correspond to each pixel.

However, the film thicknesses of the color filters 14R, 14G, and 14B of the respective colors of the substrate 12 are different from each other, whereas the film thickness of the alignment material film printed by using the alignment material printing plate 20 is different. 5 is almost uniform as shown in FIG. 5, the film surface of the alignment film formed by firing this alignment material film has the color filters 14R, 14 of the respective colors.
The surface has a step corresponding to the difference in film thickness between G and 14B.

If there is a step on the film surface of the alignment film, the alignment state of the liquid crystal molecules of the manufactured liquid crystal element is disturbed at the step of the alignment film, so that light leakage or the like occurs at the edge of each pixel. However, the display quality of the liquid crystal element deteriorates.

Therefore, when the color filters of a plurality of colors are formed in different thicknesses on the substrate on which the alignment material a is printed, the alignment material a is printed on this substrate by the following alignment. It is desirable to use a printing plate.

FIG. 7 is a plan view of an alignment material printing plate in a developed state showing a second embodiment of the present invention. (A) is an overall view, (b), (c) and (d) are plate surfaces. FIG. 3D is an enlarged view of each part of the central portion, and FIG. 3D is an enlarged view of a part of the peripheral portion of the printing plate.

The orientation material printing plate 30 of this embodiment has a color filter 14 of three colors of red, green and blue as shown in FIG.
R, 14G, and 14B are formed to have different film thicknesses, and a dummy filter having substantially the same thickness as the blue filter 14B having the largest film thickness among the color filters 14R, 14G, and 14B of each color is formed around the color filter formation region. It is used for printing the alignment material a on the substrate 12 on which 15 is formed.

The orientation material printing plate 30 is a plate surface having a size (area) corresponding to the orientation material printing area of the substrate 12, and a minute projection 31a for holding the orientation material attached to the plate surface over the entire area. , 31b are provided at close intervals, the orienting material printing plate 30 is made of a flexible resin sheet, and the projections 31a, 31b are integrally formed on the surface of the resin sheet.

The projections 31a and 31b are, for example, cylindrical, and the projections 31b on the plate peripheral portion 30b are provided at intervals s20 smaller than the intervals s11, s12, s13 of the projections 31a on the plate central portion 30a. .

The alignment material printing plate 30 is for printing the alignment material on the substrate 12 from the area where the color filters 14R, 14G and 14B are formed to the area where the dummy filter 15 is formed. The width of the peripheral edge portion 30b having a smaller width is approximately the same as the width of the dummy filter 15 on the substrate 12.

That is, in FIG. 7A, an area A'enclosed by a chain double-dashed line indicates a color filter forming area of the substrate 12, and the alignment material printing plate 30 has the center of its plate surface. The portion 30a corresponds to the color filter forming area A'of the substrate 12, and the plate surface peripheral portion 30b having a small protrusion interval corresponds to the dummy filter forming portion outside the color filter forming area A'of the substrate 12. It has become.

Further, the projection intervals s11, s12, s13 of the plate surface central portion 30a of the orientation material printing plate 30 are set to the substrate 12 described above.
The portions corresponding to the color filters 14R, 14G, and 14B of each color are different.

In FIG. 7A, the central portion 30 of the printing plate is
The portions of a corresponding to the color filters 14R, 14G, and 14B are shown separated by broken lines, R is the portion corresponding to the red filter 14R, and G is the green filter 1.
A part corresponding to 4G and a part B corresponding to the blue filter 14B.

The protrusion intervals s11, s12, s13 of the filter corresponding portions R, G, B of the plate surface central portion 30a are set according to the film thickness of the color filters 14R, 14G, 14B of the respective colors. The protrusions of the portion corresponding to the thin color filter are provided at intervals larger than the intervals of the protrusions of the portions corresponding to the thick color filters.

That is, in the substrate 12 shown in FIG. 5, the film thickness of the color filters 14R, 14G and 14B for each color is
The red filter 14R, the green filter 14G, and the blue filter 14B are made thicker in this order. Therefore, in the alignment material printing plate 30 of this embodiment, the blue color of the filter-corresponding portions R, G, B of the plate surface central portion 30a is blue. The protrusion spacing s13 of the filter corresponding portion B is minimized, and the protrusion spacing s12 of the green filter corresponding portion G is made larger than that, and
The protrusion spacing s11 of the red filter corresponding portion R is further increased.

In this embodiment, the central portion 30a of the printing plate is
All the protrusions 31a of the respective filter-corresponding portions R, G, B and the protrusions 31b of the plate surface peripheral portion 30b are arranged at the same pitch,
By changing the diameters (diameters) of the protrusions 21a and 21b of these respective portions, the protrusion intervals of the respective portions are made different from each other. However, the heights of these protrusions 21a and 21b are all the same.

Further, in this embodiment, the plate surface peripheral portion 30b is used.
The projection spacing s20 and the projection spacing s13 of the blue filter corresponding portion B of the plate surface central portion 30a are respectively the plate edge portion 30 of the printing plate 20 of the first embodiment shown in FIG.
The protrusion spacing s2 of b and the protrusion spacing s1 of the central portion 20a of the printing plate are the same (s20 = s2, s13 = s1), and the protrusion spacing s13 of the blue filter corresponding portion B and the color filter 1 of each color.
Depending on the film thickness difference between 4R, 14G, and 14B, the protrusion spacing s12 of the green filter corresponding portion G and the red filter corresponding portion R
The protrusion spacing s11 is set.

The orientation material printing plate 30 of this embodiment is also used by being attached to the peripheral surface of the orientation material printing roller, similarly to the conventional orientation material printing plate. In the transfer printing, the liquid alignment material applied to the surface of the alignment material supply body such as the alignment material supply plate or the alignment material supply roller is applied to the plate surface of the alignment material printing plate 30 to have a certain thickness, and the alignment material printing plate is used. The printing is performed by printing the alignment material attached to the plate surface of 30 on the alignment material printing area of the substrate.

FIG. 8 shows the color filters 14 for red, green and blue.
FIG. 8 is a cross-sectional view of the vicinity of an end portion of an alignment material film printed by using the alignment material printing plate 30 of the second embodiment on the substrate 12 in which R, 14G, and 14B are formed to have different film thicknesses. In addition,
Since the substrate 12 shown in FIG. 8 is the same as the substrate shown in FIG. 5, the description of the structure will be omitted by giving the same reference numerals to the drawing.

As shown in FIG. 8, when the alignment material a is transferred and printed on the substrate 12 using the alignment material printing plate 30 of the above embodiment, the alignment material a printed on the alignment material printing area of the substrate 12 is printed. The amount of printing per unit area is reduced in the peripheral portion of the alignment material printing region, and the shortage of the printing amount is offset by the rise of the peripheral portion of the printed film of the alignment material a due to surface tension. Since the film thickness of the peripheral portion of the alignment material film printed on the substrate 12 is almost the same as the film thickness of the central portion, and the peripheral portion of the alignment material film is above the dummy filter 15. In addition, the film surface of this peripheral portion is almost at the same level as the film surface of the portion on the blue filter 14B having a large film thickness.

Moreover, in the alignment material printing plate 30, of the protrusions 31a of the central portion 30a of the plate surface, the protrusion spacing s13 of the portion B corresponding to the blue filter 14B having the largest film thickness.
And the protrusion spacing s12 of the portion G corresponding to the green filter 14G having the next largest thickness is made larger than the protrusion spacing s13 of the blue filter portion B, and a portion corresponding to the red filter 14R having the smallest thickness. R protrusion interval s
Since 11 is made larger, the alignment material a is thinly printed on the portion above the blue filter 14B having the largest film thickness.
The orientation material a is printed slightly thicker on the green filter 14G having the next thickest film, and the orientation material a is printed thicker on the portion having the thinnest red filter 14R. The film surface of the alignment material a printed on the 12 color filter forming regions also has substantially the same level over the entire region.

Therefore, the color filters 14R,
If the alignment material a is printed on the substrate 12 on which 14G and 14B are provided by using the alignment material printing plate 30 of the above embodiment,
The film thickness of the peripheral portion is almost the same as the desired film thickness, and the film surface of the peripheral portion is almost at the same level as the film surface of the portion on the blue filter 14B having a large film thickness. Also, the film surfaces of the portions on the green filters 14R and 14G are at substantially the same level as the film surfaces of the portions on the blue filter 14B, and it is possible to form an alignment film having a substantially flat film surface.

The substrate provided with the color filters is not limited to the one in which the color filters 14R, 14G, and 14B of the respective colors are formed in stripes as in the substrate 12 shown in FIG. Some filters are arranged in a mosaic pattern corresponding to each pixel of the liquid crystal element, but the central part of the printing plate is divided corresponding to the mosaic array of color filters, and the projections of the corresponding parts of each color filter. By using an alignment material printing plate that has different intervals according to the film thickness of the color filters of each color, even if the color filters of each color are arranged in a mosaic pattern on the substrate, the alignment film is almost flat over the entire film surface. Can be formed.

The substrate 12 shown in FIG. 8 has the electrodes 13 for display formed on the color filters 14R, 14G and 14B, but the alignment material printing plate 30 of the second embodiment described above is different. It can also be used for printing an alignment material on a substrate having a color filter formed on a display electrode.

In the case of a substrate having a color filter formed on the display electrodes, in order to make the liquid crystal element perform color display with a good color balance, a color filter for each color,
For example, using red, green, and blue color filters as opposed to FIG.
The blue filter, the green filter, and the red filter are formed thicker in this order, but the protrusion intervals of the respective filter-corresponding portions in the central portion of the plate surface of the orientation material printing plate 30 are reversed from those in FIG. Reduce the filter-corresponding part and the red filter-corresponding part in order,
By making the distance between the protrusions of the portion corresponding to the reddish filter having the largest film thickness among the portions corresponding to the respective filters, an alignment film having a substantially flat film surface can be formed on the substrate.

[0093]

The orientation material printing plate of the present invention is applied to the surface of the orientation material supply body with a constant thickness by providing the minute protrusions at the peripheral portion of the plate surface at intervals smaller than the spacing between the protrusions at the center of the plate surface. Since the amount of the alignment material attached to the plate surface per unit area is reduced in the peripheral portion of the plate surface,
The printing amount per unit area of the alignment material printed in the alignment material printing area of the substrate is reduced in the peripheral portion of the alignment material printing area to offset the rise of the peripheral portion of the printed alignment material film due to surface tension. Therefore, if the alignment material is transferred and printed on the substrate using this alignment material printing plate,
It is possible to form an alignment film in which the film thickness of the peripheral portion is almost the same as the desired film thickness.

When the alignment material printing plate of the present invention is used for printing an alignment material on a substrate on which color filters of a plurality of colors are formed in different thicknesses, a color filter forming area on the substrate is used. A dummy filter having substantially the same thickness as the thicker color filter of the color filters of the plurality of colors is formed around the periphery of the plate, and the plate surface of the alignment material printing plate is provided with a peripheral portion with a small protrusion interval. Is a size corresponding to the dummy filter formation portion of the substrate, the film thickness of the peripheral portion is almost the same as the desired film thickness, and the film surface of the peripheral portion is a thick film surface on the color filter. It is possible to form an alignment film at the same level as the above.

Further, in this case, among the protrusions at the central portion of the plate surface of the alignment material printing plate, the protrusions at the portions corresponding to the thin color filter are separated from the protrusions at the portions corresponding to the thick color filter. If you set it at a larger interval,
Since the orientation material is printed thick on the portion above the thin color filter, and the orientation material is printed thin on the portion above the thick color filter, on the color filter formation region of the substrate, An alignment film having a substantially flat film surface and having almost no step can be formed.

[Brief description of drawings]

1A and 1B are plan views of an alignment material printing plate according to a first embodiment of the present invention in a developed state, where FIG.
Is an enlarged view of a part of the central portion of the plate surface, and FIG. 7C is an enlarged view of a part of the peripheral portion of the plate surface.

FIG. 2 is a sectional view taken along line II-II in FIG.

FIG. 3 is a sectional view taken along line III-III in FIG.

FIG. 4 is a sectional view of the vicinity of an end portion of an alignment material film printed on a substrate using the alignment material printing plate of the first embodiment.

FIG. 5 is a cross-section near the end of the alignment material film printed by using the alignment material printing plate of the first embodiment on a substrate on which red, green, and blue color filters are formed to have different film thicknesses. Fig.

FIG. 6 is a perspective view of a part of a dummy filter formed on a substrate so as to surround a color filter formation region.

FIG. 7 is a plan view of an alignment material printing plate according to a second embodiment of the present invention in a developed state, in which (a) is an overall view,
(B), (c), (d) is an enlarged view of each part of the central portion of the printing plate, and (e) is an enlarged view of a part of the peripheral portion of the printing plate.

FIG. 8 is a cross-sectional view of an edge portion of an alignment material film printed by using the alignment material printing plate of the second embodiment on a substrate on which red, green, and blue color filters are formed with different thicknesses. Fig.

FIG. 9 is a side view showing an example of a transfer printing apparatus,
(A) is a state when the alignment material is applied to the surface of the alignment material supply body, (b) is a state when the alignment material applied to the surface of the alignment material supply body is attached to the printing plate, (c) is a substrate It is a figure which shows the state in which the orientation material is printed on it.

FIG. 10 is an enlarged sectional view showing an X portion in FIG. 9C.

FIG. 11 is a plan view of a conventional alignment material printing plate in a developed state, (a) is an overall view, and (b) is an enlarged view of a part of a plate surface.

12 is a sectional view taken along line XII-XII in FIG.

FIG. 13 is a cross-sectional view near an end portion of an alignment material film printed on a substrate using a conventional alignment material printing plate.

[Explanation of symbols] 10, 12 ... Substrate 11, 13 ... Electrodes 14R ... Red filter 14G ... Green filter 14B ... Blue filter 15 ... Dummy filter 16 ... Protective film 20, 30 ... Alignment material printing plate 20a, 30a ... central part of printing plate 20b, 30b ... Plate peripheral edge 21a, 31a ... Protrusions at the center of the printing plate 20b, 30b ... Protrusions on the periphery of the printing plate

Claims (4)

(57) [Claims] 1. A printing plate used for transfer printing of a liquid alignment material applied to a surface of an alignment material supply body with a constant thickness onto an electrode formation surface of a liquid crystal element substrate, the alignment material printing of the substrate. The plate surface of a size corresponding to the region is provided with minute projections for holding the alignment material adhered to the plate surface over the entire area at close intervals, and the projections at the peripheral edge of the plate surface are the central portion of the plate surface. An alignment material printing plate, characterized in that it is provided at an interval smaller than the interval between the protrusions. 2. The orientation material printing plate according to claim 1, wherein the diameter of the protrusions at the peripheral portion of the plate surface is larger than the diameter of the protrusions at the central portion of the plate surface. 3. A substrate on which an alignment material is printed, color filters of a plurality of colors having different film thicknesses are formed, and the color filters of the plurality of colors are formed around a region where these color filters are formed. A dummy filter having substantially the same thickness as the thicker color filter is formed, and the size of the plate surface is such that the peripheral portion with a small protrusion interval corresponds to the dummy filter forming portion of the substrate. The orientation material printing plate according to claim 1 or 2, wherein 4. The protrusions in the central portion of the plate surface corresponding to the thin color filter are provided at intervals larger than the spacing of the protrusions corresponding to the thick color filter. The orientation material printing plate according to claim 3, wherein