JPH05224206A - Orientation treatment device and method for oriented film for liquid crystal - Google Patents

Abstract

PURPOSE:To prevent the process defect and nonuniformity by fiber scrap by constituting the above device and method in such a manner that a parallel spot-like UV ray is reflected by a mirror to arrive at a liquid crystal oriented film and forms an oriented surface having an oriented groove by the rotation of the mirror. CONSTITUTION:The UV laser 2 outputted from a UV laser generator 1 is converged by lenses 3, 4 to form the parallel spot-like UV ray 5, which is reflected by the mirror 6 to arrive at the liquid crystal oriented film 7 on a substrate 8. The part irradiated in the spot form on this liquid crystal oriented film 7 is recessed by a chemical reaction. One piece of the linear oriented groove is formed on the liquid crystal oriented film 7 when the mirror 6 is rotated around an axis 9 at this time. The second oriented groove is formed in parallel with the first groove when the mirror 6 is further rotated around the axis 9 in the state of slightly rotating the mirror around the axis 10. The surface of the liquid crystal oriented film 7 is subjected to the orientation treatment when such operation is repeated. The formation of the plural parallel oriented grooves is possible as well even if the substrate 8 is fed pitch by pitch in place of such mirror 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an alignment treatment apparatus and method for aligning liquid crystal molecules in a predetermined direction with respect to a liquid crystal display substrate.

[0002]

2. Description of the Related Art In a liquid crystal display device, it is necessary to orient the liquid crystal molecules in a specific direction in order to control the electro-optical characteristics of the liquid crystal. Generally, as shown in FIG. 8, for example, a polymer resin such as polyimide is used as the alignment film, and the surface of the polyimide alignment film 42 is specified by using a roller 40 having a woven cloth 41 on the surface. A rubbing method is used.

[0003]

In the conventional alignment treatment method, fiber scraps are generated from the woven cloth on the roller surface, which cannot be completely removed by the cleaning treatment after rubbing and remains attached on the polyimide alignment film. It causes a defective gap between the substrates. Also, if you rub with a roller that does not generate fiber scraps,
Although it is possible to perform a clean alignment treatment, it is difficult to perform minute alignment treatment on every corner because it is easily affected by the substrate surface step. In other words, the conventional alignment treatment method has a drawback that uniform and reproducible alignment treatment cannot be performed.

Therefore, an object of the present invention is to obtain an alignment treatment apparatus and method in which the process defects due to fiber waste and the nonuniformity of the alignment treatment are eliminated.

[0005]

The present invention is characterized in that an alignment treatment apparatus and method for aligning liquid crystal molecules in a predetermined direction with respect to a substrate is performed by irradiating an ultraviolet laser.

[0006]

In the surface area of the alignment film irradiated with the ultraviolet laser, the surface of the polymer resin is vaporized by oxidizing the ozone in the atmosphere generated by the irradiation of the ultraviolet laser. The surface is recessed only in the area irradiated with the ultraviolet laser. In the present invention, since the unevenness is provided on the surface of the alignment film by using a chemical reaction in a non-contact manner, it is possible to solve the problems of the process defect due to the fiber scrap of the conventional method and the nonuniformity of the alignment treatment, and the uniform and reproducible alignment It becomes possible to perform processing.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. In FIG. 1, the ultraviolet laser 2 output from the ultraviolet laser generator 1 includes a lens 3 and a lens 4.
Is squeezed by to become parallel spot-shaped UV rays 5,
It is reflected by the mirror 6 and reaches the liquid crystal alignment film 7 on the substrate 8. The spot-shaped irradiation portion on the liquid crystal alignment film 7 is recessed by a chemical reaction. Here, when the mirror 6 is rotated about the axis 9, one linear alignment groove 11 is first formed on the liquid crystal alignment film 7 as shown in FIG. further,
When the mirror 6 is rotated about the axis 10 while being slightly rotated about the axis 10, the second linear alignment groove 11 becomes 1
It is formed parallel to the main line. By repeating the same operation, the alignment treatment is performed on the liquid crystal alignment film 7. In addition,
It is possible to form a plurality of parallel alignment grooves 11 even if the substrate 8 is pitch-fed by a moving stage (not shown) instead of rotating the mirror about the axis 10.

In the present embodiment, the alignment treatment can be performed without a mask by narrowing the ultraviolet laser in a spot shape and scanning in the same direction. Next, FIG. 3 showing the second embodiment will be described. A mask 21 having substantially the same size is provided on the substrate 8. As shown in FIG. 4, the mask 21 has a plurality of slits 22 for performing an alignment treatment. The ultraviolet laser may be narrowed down like the spot 23 so that one of the slits 22 can be irradiated.
It may be narrowed to a larger size like the spot 24 so as to straddle a plurality of points.

When the spot 23 or the spot 24 is scanned over the entire area of the mask, the ultraviolet rays 5 reach the liquid crystal alignment film 7 only in the slits 22, so that a chemical reaction is performed to form a slit-like alignment treatment. Next, FIG. 5 showing the third embodiment will be described. A mask 31 having a small size is provided on the substrate 8 to divide the substrate area into a plurality of areas. The mask 31 has a plurality of slits 32 for performing an alignment treatment as shown in FIG. The ultraviolet laser squeezes the slit 32 of the mask 31 into a large spot like the spot 30 so that the slit 32 can be collectively irradiated. It should be noted that the ultraviolet lasers that are collectively irradiated do not have to be circular like the spot 30, and a shaping lens (not shown) is used instead of the lenses 3 and 4 so that the slit 32 in the mask 31 can be irradiated without waste. The irradiation shape may be rectangular or the like. When the mask 31 is irradiated with the ultraviolet laser like the spot 30 all together for a certain period of time, the ultraviolet rays reach the liquid crystal alignment film 7 only in the slits 32, so that they are recessed in a slit shape by a chemical reaction, and they are directly below the mask 31. Only the orientation process is performed.

Subsequently, the substrate 8 and the mask 31 are relatively moved by the size of the mask 31. For example, the substrate 8 may be moved by a moving table (not shown). Mask 31
If the mask 31 is collectively irradiated with ultraviolet rays for a certain period of time while moving relative to the substrate 8, a portion adjacent to the previously-aligned region is aligned. If the above operation is performed on the entire surface of the substrate by step-and-repeat, the entire surface of the substrate can be oriented.

FIG. 7 is a sectional view of a liquid crystal display device which has been subjected to the alignment treatment according to the present invention. A glass substrate 33 in which a transparent electrode 34 and a polyimide alignment film 35 are laminated, and a glass substrate 3 in which an active element layer 38 and a polyimide alignment film 37 are laminated
The liquid crystal 36 is enclosed by 9 and.

[0012]

As described above, according to the present invention, since the alignment treatment is carried out by utilizing the chemical reaction by the ultraviolet laser, there is no generation of fiber scraps and it is possible to reduce the display defects caused by the foreign matters. Further, there is an effect that cleaning after the alignment treatment is unnecessary and the process can be simplified.

Further, there is an effect that fine alignment processing can be realized uniformly and with good reproducibility in every corner without being affected by the steps on the substrate surface.

[Brief description of drawings]

FIG. 1 is an explanatory diagram of an example of the present invention.

FIG. 2 is an explanatory diagram for supplementing FIG.

FIG. 3 is an explanatory diagram of a second embodiment of the present invention.

FIG. 4 is an explanatory diagram for supplementing FIG.

FIG. 5 is an explanatory diagram of a third embodiment of the present invention.

6 is an explanatory diagram for supplementing FIG.

FIG. 7 is a cross-sectional view of a liquid crystal display device manufactured according to the present invention.

FIG. 8 is an explanatory diagram showing a conventional orientation method.

[Explanation of symbols]

 1 Ultraviolet Laser Generator 2 Ultraviolet 3 Lens 4 Lens 5 Parallel Spot-shaped Ultraviolet 6 Mirror 7 Liquid Crystal Alignment Film 8 Substrate 9 Axis 10 Axis 11 Alignment Groove 21 Mask 22 Slit 23 Spot 24 Spot 30 Spot 31 Mask 32 Slit 33 Glass Substrate 34 Transparent Electrode 35 Polyimide Alignment Film 36 Liquid Crystal 37 Polyimide Alignment Film 38 Active Element Layer 39 Glass Substrate 40 Roller 41 Woven Cloth 42 Polyimide Alignment Film 43 Transparent Electrode 44 Glass Substrate

 ─────────────────────────────────────────────────── ─── Continued front page (72) Inventor Yoshimi Kuroda 6-31-1, Kameido, Koto-ku, Tokyo Seiko Electronics Co., Ltd. (72) Hiroshi Ishijima 6-31-1, Kameido, Koto-ku, Tokyo No. Seiko Electronics Industry Co., Ltd. (72) Inventor Masataka Shinogi 6-31-1, Kameido, Koto-ku, Tokyo Within Seiko Electronics Industry Co., Ltd.

Claims (4)

[Claims] 1. An alignment treatment device for aligning liquid crystal molecules in a predetermined direction with respect to a substrate, comprising: an ultraviolet laser generator; and a lens for shaping the ultraviolet laser emitted from the ultraviolet laser generator into a spot shape. And a scanning mirror for linearly irradiating the entire surface of the liquid crystal alignment film on the substrate with the ultraviolet laser in the same direction. 2. An alignment method comprising forming an alignment surface by irradiating a liquid crystal alignment film with an ultraviolet laser in the form of a spot, irradiating the liquid crystal alignment film and scanning in the same direction. 3. A mask having substantially the same dimensions is provided on a substrate, and the mask has a slit for performing an alignment treatment, and an ultraviolet laser is irradiated onto the mask to scan the mask to form an alignment surface. And the orientation method. 4. A substrate is provided with a mask having a small size that divides a substrate area into a plurality of areas, and the mask has slits for performing an alignment treatment, and the ultraviolet laser collectively irradiates the mask for a predetermined time. An orienting method characterized in that a part of the substrate is orientated, the substrate and the mask are subsequently moved relative to each other, and the adjacent part is orientated over the entire surface of the substrate.