JPH086027A - Transfer device of rugged pattern to oriented film - Google Patents

Abstract

PURPOSE:To provide a transfer device which is capable of transferring rugged patterns with lessened unevenness even in the case of forming of an oriented film on a substrate having come waving or ruggedness or inclination and does not peel a part of an oriented film prepn. layer at the time of peeling and does not generate peeling defects. CONSTITUTION:This transfer device of the rugged patterns is constituted to form the oriented film by pressing a mold member formed with the rugged patterns to the oriented film prepn. layer on a substrate, thereby transferring the rugged patterns atop the oriented film prepn. layer. The device has a press base body 11 consisting of a rigid material, an elastic member 12 arranged to face the press base body 11 and the sheet-like mold member 13 disposed on the side of the elastic member 12 where the member does not face the press base body 11.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transfer device for an uneven pattern which can be suitably used when forming an alignment film such as a liquid crystal substrate.

[Prior art]

An alignment film is formed on the inner surface of a substrate that constitutes a liquid crystal element in order to align the liquid crystal in a predetermined direction. As the alignment film, conventionally, a rubbing cloth which has been rubbed with a surface of an alignment film preparation layer (resin film) to perform a specific alignment treatment has been widely used. However, this rubbing process is a process involving dust generation, and the surface of the alignment film is easily contaminated with dust during the process.
There is a problem that the alignment property of the alignment film is impaired by this contamination.

In order to address such a problem, the present inventors have studied the formation of an alignment film by the stamping method, and have made various developments and studies. The alignment film of the liquid crystal substrate is provided on the surface of the highly rigid substrate body made of glass or the like, and is usually formed to be extremely thin such as 1 μm or less in order to reduce the driving voltage of the liquid crystal element. Therefore, there is a problem in that a good uneven pattern cannot be formed by simply pressing the mold, as in the case of forming an uneven pattern on a flexible and thick plastic film. That is, in order to form the uneven pattern on the surface of the thin alignment film, it is necessary to accurately press the mold with a uniform pressure on the resin-made alignment film preparation layer to be the alignment film. To this end, when pressing with a press machine, the surface flatness and parallelism of the die plate and die set of the press machine are increased, and the in-plane pressure distribution when pressing the die to the alignment film preparation layer is made uniform. It is necessary.

[0004]

However, as a result of investigations by the present inventors, even if the surface flatness of the mold is sufficiently enhanced and the pressing is performed, the transfer of the mold to the alignment film preparation layer is completed. It turns out that there are things that cannot be done. This is Figure 9
The transparent substrate 2 such as glass on which the alignment film preparation layer 1 shown in (a) is formed usually has fine undulations, unevenness or inclination, and may have uneven thickness. Therefore, it is caused by some undulations, unevenness or inclination remaining on the upper surface of the substrate 2 even when the surface finishing is sufficiently performed by performing a pretreatment such as polishing. That is, when pressing is performed using a transfer device including a press substrate 3 having high flatness, a sheet-shaped elastic member 4 and a plate-shaped mold member 5 attached to the press substrate 3, FIG.
As shown in (b), there is a problem in that a region where the mold member 5 cannot be pressed is generated on the alignment film preparation layer 1, and this region leads to alignment failure, causing display failure of the liquid crystal display device.

Further, when the mold member 5 is released from the alignment film preparation layer 1 after the uneven pattern is formed on the alignment film preparation layer 1 by the mold member 5, the mold member 5 and the alignment film preparation layer 1 are easily adhered to each other. In the case of using a material, there is a problem that a part of the alignment film preparation layer 1 is peeled off and adheres to the surface of the mold member 5, causing a part of the alignment film to be damaged and causing display unevenness. It was Although the alignment film is usually made of aromatic polyamide, when the mold member 5 is made of nickel, for example, such a problem of peeling of the alignment film has been remarkable.

The present invention has been made in view of the above circumstances, and even when an alignment film is formed on a substrate having some inclination, unevenness, or waviness, the unevenness pattern has a small unevenness. It is an object of the present invention to provide a transfer device capable of performing the above transfer and not causing a part of the alignment film preparation layer to be peeled off at the time of releasing the mold and causing no peeling defect.

[0007]

In order to solve the above-mentioned problems, according to the first aspect of the present invention, a mold member having a concavo-convex pattern is pressed against an alignment film preparation layer on a substrate to form an upper surface of the alignment film preparation layer. In an uneven pattern transfer device for forming an alignment film by transferring an uneven pattern, a press base made of a rigid body, an elastic member arranged to face the press base, and the elastic member not facing the press base. A sheet-shaped mold member is provided on the side.

According to a second aspect of the present invention, in order to solve the above problems, the elastic member according to the first aspect is attached to the surface of a press base, and the mold member is attached to the surface of the elastic member. Is.

According to a third aspect of the present invention, in order to solve the above problems, the press substrate according to the first or second aspect is formed into a flat plate shape.

According to a fourth aspect of the present invention, in order to solve the above problems, the press substrate according to the first or second aspect is formed into a roller shape.

In order to solve the above-mentioned problems, the invention according to claim 5 provides the mold member according to claim 1, 2, 3 or 4.
It is formed with a thickness in the range of 0.001 mm or more and 0.2 mm or less.

In order to solve the above-mentioned problems, the invention according to claim 6 covers the surface of the mold member according to claim 1, 2, 3, 4 or 5 with a coating layer made of gold or a gold alloy, or copper or a copper alloy. Is formed.

[0013]

Since the thin die member is attached to the press base through the elastic member, when the die member is pressed against the alignment film preparation layer to transfer the concave-convex pattern, the alignment film preparation layer slightly moves to the press base. Even if it is inclined, the elastic member can be deformed in accordance with this inclination, so that the uneven pattern of the mold member is surely pressed against the entire surface of the alignment film preparation layer. Furthermore, when a die member having a thickness of 0.001 to 0.2 mm is used, the basic alignment film preparation layer has some undulations, irregularities or inclinations due to the fine undulations or irregularities or inclinations of the substrate. However, since the elastic member and the mold member are surely deformed and follow the waviness, the unevenness, or the inclination, the uneven pattern of the mold member is reliably pressed against the entire surface of the alignment film preparation layer. That is, when a die member having a thickness of 0.2 mm or less is used, the elastic member and the die member sufficiently follow each other according to the fine waviness, unevenness or inclination of the substrate or the alignment film preparation layer. Further, if the thickness is 0.001 mm or more, there is no problem of breakage in handling.

Further, when a coating layer of gold or copper is formed on the surface of the mold member, the alignment film preparation is performed when the mold member is released from the alignment film preparation layer by transferring the uneven pattern to the alignment film preparation layer. No problem of adhesion of the layers to the mold parts occurs. The press base may be a flat plate or a roller. A flat press substrate with an elastic member and a mold member attached can transfer the uneven shape by a single pressing operation. With a roller substrate, the substrate is an alignment film preparation layer. The uneven pattern can be transferred by pressing while rotating along.

[0015]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 shows a first embodiment of a transfer device according to the present invention. A transfer device 10 of this example is a press substrate 1
1 and a sheet-like elastic member 12 attached to the lower surface thereof
And a sheet-shaped mold member 13 attached to the lower surface thereof.

The press substrate 11 is made of a metal material having high rigidity, and the flatness of its lower surface is sufficiently enhanced by means such as polishing. The surface roughness of the press substrate 11 is preferably adjusted to, for example, about ± 10 μm. The elastic member 12 is made of a resin layer having a thickness of about 0.8 to several mm, and it is preferable to use silicon rubber or the like as its constituent material. The mold member 13 is made of a material such as nickel, gold and copper, and preferably has a thickness of 0.1.
It is formed to have a thickness of 001 mm or more and 0.2 mm or less, and has a concavo-convex pattern formed on the surface of a flat plate-shaped substrate. The surface of the mold member 13 is covered with a coating layer made of gold or gold alloy, or copper or copper alloy. This coating layer is formed by coating the concavo-convex pattern with a film forming means such as vapor deposition or sputtering and has a thickness of 0.1 to 0.5 μm.

In FIG. 1, reference numeral 15 is a transparent substrate made of glass or the like, and 16 is an alignment film preparation layer made of aromatic polyamide and coated on the upper surface of the substrate 15. Although the undulations of the substrate 15 are emphasized in the drawings, the warpage and unevenness of the substrate 15 are actually on the order of microns or less.

In order to transfer the concavo-convex pattern to the alignment film preparation layer 16 using the transfer device 10 having the above structure, first, the mold member 13 of the transfer device 10 is directed toward the alignment film preparation layer 16 as shown in FIG. Then, the alignment film preparation layer 16 is pressed. Board 1
Even if there are undulations and some unevenness in the mold 5, the mold member 13 is thin and excellent in flexibility, and the elastic member 12 also has elasticity and can be elastically deformed. As shown in FIG. Since the undulation and some unevenness can be absorbed by the deformation of the elastic member 12, the mold member 13 can be reliably pressed against the alignment film preparation layer 16. Further, the processing temperature at this time is 10
Range of 0 to 200 ° C, pressing force is 50 to 100 kg / c
A range of about m ² is preferable.

As a result, an uneven pattern corresponding to the uneven pattern of the mold member 13 is transferred onto the alignment film preparation layer 16, whereby the alignment film preparation layer 16 becomes an alignment film. When the transfer of the uneven pattern is completed, the mold member 13 is peeled off from the alignment film. At this time, since the mold member 13 has a coating layer made of gold, a gold alloy, copper, or a copper alloy on the surface of the mold member 13. , A part of the alignment film does not easily adhere to the mold member 13,
Since it is not peeled off to the mold member 13 side, it is possible to reliably transfer the uneven pattern. This is because the alignment film preparation layer 16 and the coating layer on the surface of the mold member 13 are difficult to adhere due to the relationship between the surface energy of the aromatic polyamide forming the alignment film preparation layer 16 and gold or copper. Thereby, the uneven pattern can be transferred without damaging a part of the alignment film preparation layer 16, and the alignment film having the uneven pattern can be manufactured.

From the relationship of the surface energy of gold or copper with respect to the alignment film preparation layer 16, it can be understood that they are basically hard to adhere to each other. However, a gold-based alloy in which other elements such as nickel are added to gold. Alternatively, the same effect can be obtained even with a copper alloy in which other element such as nickel is added to copper.

FIGS. 3 and 4 are for explaining the second embodiment of the present invention. In the transfer device 20 of this embodiment, a roller (press base) 21 and this roller 21 are provided separately. Flat elastic member 22 and the elastic member 2
2 and a mold member 23 integrated on the lower surface of the mold 2. The elastic member 22 is the elastic member 1 of the previous embodiment.
2 has the same structure as that of the mold member 23, and the mold member 23 has the same structure as the mold member 13 of the previous embodiment.

In the apparatus of this example, the mold member 13 is placed on the alignment film preparation layer 16 of the substrate 15 as shown in FIG. 3, and from this state, the roller 21 is pressed against the elastic member 22 with a predetermined pressure and the roller 21 is pressed. The substrate 15 is rotationally moved from one side to the other side. By this operation, the elastic member 22 and the mold member 2
Reference numeral 3 transfers the uneven pattern of the mold member 23 to the alignment film preparation layer 16 while deforming in accordance with the undulations and unevenness of the substrate 15. Therefore, by using the transfer device 20 of this example, the same effect as in the case of the first embodiment can be obtained.

FIGS. 5 and 6 are for explaining the third embodiment of the present invention. The transfer device 30 of this embodiment is a roller (press base) 31 and a roller 31 attached to the surface thereof. The sheet-shaped elastic member 22 and the mold member 33 attached to the surface of the elastic member 32 are provided. The elastic member 32 has the same structure as the elastic member 12 of the previous embodiment, and the mold member 33 has the same structure as the mold member 13 of the previous embodiment.

In the apparatus of this example, as shown in FIG. 6, the roller 31 is placed on the alignment film preparation layer 16 of the substrate 15, and from this state, the elastic member 32 on the roller surface is applied to the alignment film preparation layer 16 with a predetermined pressure. While pressing the roller 31 to the substrate 1
5 is rotated from one side to the other side. By this operation, the elastic member 32 and the mold member 33 are deformed according to the warp and the unevenness of the substrate 15, respectively, and the uneven pattern of the mold member 33 is transferred to the alignment film preparation layer 16. Therefore, the transfer device 30 of this example
By using, it is possible to obtain the same effect as in the case of the first embodiment.

FIG. 7 shows an example of an alignment film having a concavo-convex pattern formed by using the transfer device of the first to third embodiments. The concavo-convex pattern of the alignment film 40 in this example has a preferable shape for defining the pretilt angle of the liquid crystal. The concavo-convex pattern of this example is an aggregate shape of a large number of triangular convex portions 41 formed along the first direction and the second direction of the arrow in the figure, and the concavo-convex pattern along the first direction is formed. The pitch P ₁ is made shorter than the pitch P ₂ along the second direction. The value of the pitch P ₁ is, for example, 3.0 μm or less,
The value of the pitch P ₂ can be, for example, 50 μm or less. Further, the height (depth) d ₁ of the convex portion 41 is 0.5 μ, for example.
It can be m or less.

[Test Example 1] The structure as shown in FIG. 1 has a flat plate type substrate made of carbon tool steel (JIS standard SK4) and a sheet-like elasticity made of silicon rubber having a thickness of 0.8 mm. Member and a mold member made of nickel are integrated, and an alignment film preparation layer made of an aromatic polyamide having a thickness of 0.2 μm is formed on a glass substrate having a thickness of 1.1 mm, and an uneven pattern is formed on the glass substrate. Was tested. The pressure during transfer was 100 kg / cm ² . The concavo-convex pattern is a concavo-convex pattern having a shape as shown in FIG. 7, in which the pitch in the first direction is 0.3 μm and the pitch in the second direction is 2 μm.
m, and the height of the convex portion was 0.2 μm.

When the transfer is performed under the above conditions, the thickness is 3 mm, 1 mm, 0.5 mm, 0.2 mm, 0.05.
mm, 0.015 mm, 0.005 mm, 0.001 mm
Eight types of transfer devices were prototyped using the eight types of mold members set for each, and the transfer test of the uneven pattern was performed for each. In addition, the thickness of the uneven surface is 0.1 μm
The gold vapor deposition film is formed. The thickness is 0.001m
Attempts were made to produce mold members of less than m, but they could not be made because of insufficient strength. Table 1 shows the results of the interference light measurement test and the transfer rate measurement test performed on the obtained alignment film. In the interference light measurement test, the result of visually observing the presence or absence of interference light generated when the alignment film is irradiated with light is shown by the area. An example of this state is schematically shown in FIG. In FIG. 8A, the interfering light can be recognized in the transferred area A, and the transferred area B is not transferred.
No interfering light will be observed.

In the transfer rate measurement test, the ratio of the groove depth of the concave-convex pattern of the obtained alignment film to the groove depth of the concave portion of the concave-convex pattern of the mold member was measured as the transfer rate. The groove depth was determined as an average in-plane value by an AFM (atomic force microscope) and used as the groove depth.

[0029]

[Table 1]

As is clear from Table 1, when a die member having a thickness of 0.2 mm was used, the generation area of the interference light was almost 100%, and it was clear that the transfer was completed. However, it was revealed that the transfer rate in that case can be set to a sufficiently high value of about 90%. Further, it was found that the transfer rate was 95% when the thickness of the mold member was 0.015 mm or less.

[Test Example 2] Next, transfer using the above-mentioned mold member having a thickness of 0.05 mm and using a coating layer formed on the surface of the mold member made of any one of gold, copper and nickel A test for observing whether or not the peeled alignment film preparation layer is attached to the surface of the mold member was performed when three types of prototypes were prototyped and an uneven pattern was transferred to each of them. As a result, in the case of the nickel coating layer, the peeled portion having a diameter of 0.5 to 3 mm adheres in a spot-like shape as shown in FIG. 8B, and the adhesion region with the alignment film in this example is 30. It was found to be below%. In the transfer device using the mold member having the gold coating layer and the copper coating layer, the phenomenon that the alignment film preparation layer adhered to the mold member was not observed.

[0032]

As described above, according to the present invention, since a thin mold member is attached to the press base through the elastic member, when the mold member is pressed against the alignment film preparation layer to transfer the uneven pattern, Even if the upper surface of the substrate is not parallel to the base but is slightly inclined, the elastic member is deformed and follows this inclination, so that the uneven pattern of the mold member can be reliably pressed against the entire surface of the alignment film preparation layer, A sufficient transfer rate can be obtained. Therefore, even when transferring the uneven pattern to the alignment film preparation layer formed on the substrate having a slight inclination,
It is possible to manufacture an alignment film having a uniform uneven pattern formed on the entire surface. Next, as a mold member, the thickness is 0.001 to 0.2.
In the case where the alignment film preparatory layer has a slight waviness, unevenness, or inclination due to the fine waviness, unevenness, or inclination of the substrate, an elastic member is used in accordance with the waviness, unevenness, or inclination. Since the mold member deforms and follows, the uneven pattern of the mold member can be surely pressed against the entire surface of the alignment film preparation layer, and a sufficient transfer rate can be obtained. Therefore, even when transferring a concavo-convex pattern to the alignment film preparation layer formed on a substrate having some undulations, concavities and convexities or inclination, a high-quality alignment film having a uniform concavo-convex pattern formed on the entire surface is manufactured. be able to.

Further, if a gold or copper coating layer is formed on the surface of the mold member, the alignment film can be released from the alignment film preparation layer by transferring an uneven pattern to the alignment film preparation layer. The preparation layer does not adhere to the mold member and peel off. Therefore,
It is possible to obtain an alignment film having no defects such as peeled portions. Further, the base may be a flat plate or a roller. With a flat plate-shaped base to which an elastic member and a mold member are attached, it is possible to transfer the uneven shape to the alignment film preparation layer by one pressing operation. With a roller-shaped base, this base is placed on the substrate. It is possible to transfer the uneven pattern of the mold member to the alignment film preparation layer on the substrate by pressing while rotating along the alignment film preparation layer.

[Brief description of drawings]

FIG. 1 is a side view showing a first embodiment of a transfer device according to the present invention.

FIG. 2 is a side view showing a state where an uneven pattern is transferred to an alignment film preparation layer on a substrate by the transfer device shown in FIG.

FIG. 3 is a side view showing a second embodiment of the transfer device according to the present invention.

FIG. 4 is a side view showing a state where an uneven pattern is being transferred to an alignment film preparation layer on a substrate by the transfer device shown in FIG.

FIG. 5 is a side view showing a third embodiment of the transfer device according to the present invention.

FIG. 6 is a side view showing a state in which an uneven pattern is transferred to the alignment film preparation layer on the substrate by the transfer device shown in FIG.

FIG. 7 is an enlarged perspective view showing an example of the obtained alignment film.

8A is a diagram showing a test result of an interference light measurement test performed in a test example, and FIG. 8B is a diagram showing a peeling test result performed in a test example.

FIG. 9A is a side view showing an example of a conventional transfer device, and FIG. 9B is a side view showing a state where transfer is being performed by the conventional transfer device.

[Explanation of symbols]

 10, 20, 30 Transfer device 11 Press base 12, 22, 32 Elastic member 13, 23, 33 Mold member 15 Substrate 16 Alignment film preparation layer 21 Roller (press base) 31 Roller (press base)

Continued Front Page (72) Inventor Mitsuru Kano 1-7 Yukiya Otsukacho, Ota-ku, Tokyo Alps Electric Co., Ltd.

Claims (6)

[Claims] 1. An uneven pattern transfer device for forming an alignment film by pressing a mold member on which an uneven pattern is formed against an alignment film preparation layer on a substrate to transfer the uneven pattern onto the upper surface of the alignment film preparation layer, A press base made of a rigid body, an elastic member arranged to face the press base, and a sheet-shaped mold member provided on a side of the elastic member not facing the press base. Transferring device for uneven pattern to the alignment film. 2. The uneven pattern of the alignment film according to claim 1, wherein the elastic member is attached to a surface of a press base, and the mold member is attached to a surface of the elastic member. Transfer device. 3. The transfer device for an uneven pattern onto an alignment film according to claim 1, wherein the press base has a flat plate shape. 4. The transfer device for an uneven pattern onto an alignment film according to claim 1, wherein the press base is roller-shaped. 5. The mold member has a length of 0.001 mm or more, and 0.01 mm or more.
The transfer device for transferring an uneven pattern to an alignment film according to claim 1, wherein the transfer device is formed to have a thickness of 2 mm or less. 6. The alignment film according to claim 1, wherein a coating layer made of gold, a gold alloy, copper or a copper alloy is formed on the surface of the mold member. Transfer device for uneven patterns against.