JP2013148852A - Rubbing cloth material - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rubbing cloth material suited for manufacturing IPS-mode or FFS-mode liquid crystal display elements capable of achieving a low pretilt angle and strong anchoring energy by rubbing process.SOLUTION: Pile yarns including inorganic particulates are used for multiple pile yarns woven in a ground weave comprising warps and wefts. Rubbing process is performed by the pile yarns including the inorganic particulates to provide a liquid crystal display element having a low pretilt angle and large anchoring energy in an azimuth direction. Namely, a high-contrast IPS-mode or FFS-mode liquid crystal display element without burn-in can be thus provided.

Description

  The present invention relates to a cloth material for rubbing used in a liquid crystal display element manufacturing process.

  The liquid crystal display element is characterized by thinness, light weight, and low power consumption, and is indispensable in daily life such as a television, a notebook computer, a mobile phone, and an electronic book. The display quality is determined by the liquid crystal molecular arrangement in the device and the intermolecular interaction at the liquid crystal-alignment film interface.

  Current liquid crystal display methods are roughly classified into a method in which liquid crystal molecules are arranged substantially parallel to the substrate surface when no voltage is applied and a method in which liquid crystal molecules are arranged substantially vertically. The former method includes a TN (twisted nematic) mode in which the liquid crystal molecular alignment is twisted by 90 ° in the element and an electric field is applied in a direction perpendicular to the substrate surface, and an electric field parallel to the substrate surface without the liquid crystal molecular alignment being twisted. Are IPS (in-plane switching) mode and FFS (fringe field switching) mode, both of which are rubbed in the liquid crystal element manufacturing process.

  Here, the rubbing treatment is rubbing the alignment film surface in a certain direction with a pile cloth material. By this operation, the polymer chain on the alignment film surface is stretched, and the liquid crystal is aligned along the alignment direction of the polymer chain. The molecules are arranged.

  As shown in FIGS. 1 and 2, the pile fabric material has a structure in which a cut pile 3 having a pile length of about several millimeters is woven in the warp direction in the ground structure composed of the warp 1 and the weft 2. Such a pile fabric is wound around the outer periphery of the rotating roller and brought into contact with the substrate surface while being rotated. By such rubbing treatment, the surface of the alignment film on the substrate surface is stretched in a certain direction. Further, depending on the rubbing treatment conditions, fine rubbing traces in a certain direction may be formed. FIG. 1 is used when cut piles are woven into a W shape and are woven mainly with long fiber yarns. FIG. 2 is used when a cut pile is woven into a V-shape and is woven mainly with spun yarn.

  FIG. 3 schematically shows the arrangement of liquid crystal molecules on the surface of the alignment film subjected to the rubbing treatment. By the rubbing process, the liquid crystal molecules 31 are arranged in a predetermined direction with a certain inclination with respect to the substrate surface. The tilt angle θp at this time is referred to as a pretilt angle.

  When the rubbing treatment is performed using such a pile fabric material, the pile yarns have high napping properties, fineness, and degree of opening, which greatly affects the uniformity of the rubbing treatment, that is, the uniformity of the pretilt angle and the uniformity of the orientation direction. In order to influence, various measures have been taken to improve uniformity. For example, in Patent Document 1, a cut pile made of viscose rayon filament is inclined at a predetermined angle in the warp direction of the ground structure, so that the fine crease structure of the viscose rayon filament contacts the substrate surface in an inclined state. Thus, it is described that a finer alignment process is possible. Patent Document 2 describes that an improved cotton yarn from which twist of each short cotton fiber is removed by mercerization is used as a cut pile yarn. Japanese Patent Application Laid-Open No. H10-228561 describes that a viscose rayon yarn, a cupra yarn or the like is used as a pile yarn and subjected to a resin processing to perform shape stabilization processing.

  As described above, the liquid crystal display characteristics greatly depend on the liquid crystal molecular arrangement in the device and the intermolecular interaction at the liquid crystal-alignment film interface, which are defined by the pretilt angle and the anchoring energy. The pretilt angle is the tilt angle of the liquid crystal molecules from the substrate surface, and the anchoring energy is the energy required to move the liquid crystal molecules 41 at the initial pretilt angle as shown in FIG. For the sake of convenience, this anchoring energy includes energy Aθ (polar anchoring energy) necessary for moving in the normal direction of the substrate and energy Aφ (anchoring in the azimuth direction) necessary for moving in a direction parallel to the substrate surface. (Ring energy).

  Of the display modes in which liquid crystal molecules are aligned by rubbing, the IPS (in-plane switching) mode and the FFS (fringe field switching) mode have good viewing angle characteristics and display image distortion due to pressing is small. Many liquid crystal display devices have been adopted.

  However, these display modes have a problem that a high contrast ratio cannot be obtained due to thermal disturbance or difficulty in rubbing the electrode wiring. Further, there is a problem that the response when the applied voltage is lowered or removed, that is, the falling response becomes an afterimage and is recognized as burn-in.

Registered Utility Model No. 3032820 Registered Utility Model No. 3045464 JP 2002-148628 A

IEICE Transactions C Vol. J83-C No. 2 pp. 151-159 February 2000

  It is effective to reduce the pretilt angle of liquid crystal molecules to suppress light leakage in the oblique direction and light leakage in the vicinity of the electrode wiring, and to obtain a high contrast ratio, and to reduce image sticking, It is already known that it is effective to increase the anchoring energy and speed up the fall response, and the development of alignment film materials has been actively promoted so far. An alignment film surface that realizes directional anchoring energy has not yet been obtained.

  The pretilt angle and anchoring energy of a liquid crystal material are determined by the intermolecular interaction between the liquid crystal material and the alignment film material in the vicinity of the interface, and are largely dependent on the molecular structure and polarity of the liquid crystal material or alignment film material used. It depends. In that sense, the research and development so far has mainly been the development of liquid crystal materials or alignment film materials. For example, Ishihara et al. Reported the dependence of the pretilt angle and anchoring energy on the liquid crystal / alignment film molecular structure (Non-Patent Document 1).

  On the other hand, as shown in FIG. 5, the liquid crystal molecules 51 enter the alignment film molecular chains 52 at the liquid crystal-alignment film interface, and the pretilt angle and anchoring energy vary depending on the alignment and density of the alignment film molecular chains 52. change. That is, the pretilt angle and anchoring energy also change depending on the rubbing conditions.

  Conventionally, much research and development has been made on the liquid crystal-alignment film interface, but there has been no idea of controlling the pretilt angle and anchoring energy with a rubbing cloth material. As a result of diligent research focusing on the rubbing cloth material, the present inventors have been able to form an alignment film interface that has a low pretilt angle and a large anchoring energy in the azimuth angle direction. The material was developed.

  The rubbing cloth material according to the present invention is a rubbing cloth material comprising a ground structure woven by warps and wefts and a large number of pile yarns woven into the ground structure and protruding from the ground structure. Is a cut pile yarn containing inorganic fine particles.

  The rubbing cloth material of the present invention is a rubbing cloth material using pile yarn containing inorganic fine particles, which can lower the pretilt angle of liquid crystal molecules, and further increase anchoring energy in the azimuth direction. Since it can be enlarged, it is most suitable for a rubbing cloth material used in a manufacturing process of an IPS mode or FFS mode liquid crystal display element that switches horizontally aligned liquid crystal molecules within a substrate surface. That is, by using the rubbing cloth material of the present invention, the contrast ratio of the IPS mode or FFS mode liquid crystal display element can be increased, and the image sticking phenomenon that is a display problem can be greatly reduced. Target value is extremely high.

It is a schematic diagram of the W-shaped woven structure of the cloth material for rubbing. It is a schematic diagram of the V-shaped woven structure of the cloth material for rubbing. It is a figure for demonstrating a liquid crystal pretilt angle. It is a figure for demonstrating anchoring energy. It is a schematic diagram for demonstrating the appearance of a liquid crystal-alignment film interface. It is a figure for demonstrating a mode when the film | membrane surface state is observed by laser light scattering. Cross-sectional photograph of viscose rayon filament containing titanium dioxide of the present invention

Hereinafter, the embodiment regarding the cloth material for rubbing concerning this invention is explained in full detail.
Evaluation of the rubbing cloth material is performed by preparing a test cell using an alignment film substrate that has been subjected to alignment treatment under predetermined rubbing conditions, encapsulating p-type nematic liquid crystal, and then anchoring the liquid crystal pretilt angle and azimuth angle direction. This was done by measuring energy.

  The rubbing conditions used in the examples of the present invention were 1100 rpm for the roller rotation speed, 50 mm / second for the stage feed speed, and 0.3 mm for the push-in amount, but this does not limit the present invention.

  The test cell for measuring the pretilt angle is 6.0 μm after rubbing two glass substrates having a polyimide alignment film SE-6514 (manufactured by Nissan Chemical Industries, Ltd.) having a dry film thickness of 50 nm under predetermined rubbing conditions. This is a homogeneous cell produced by bonding via spacer beads and encapsulating p-type nematic liquid crystal MLC-3007 (manufactured by Merck) under a reduced pressure atmosphere. The pretilt angle was measured by a general-purpose ellipsometer Optipro manufactured by Shintec Corporation.

  Further, the test cell for measuring the anchoring energy in the azimuth angle direction includes two glass substrates having a polyimide alignment film SE-6514 (manufactured by Nissan Chemical Industries, Ltd.) formed with a dry film thickness of 50 nm under predetermined rubbing conditions. The two TN cells are bonded together via 5.5 μm spacer beads, and one of the TN cells is a p-type nematic liquid crystal MLC-3007 (made by Merck) that does not contain a chiral material. The other TN cell was filled with p-type nematic liquid crystal MLC-3007 (Merck) containing chiral material S-811 (Merck). The anchoring energy in the azimuth angle direction was calculated by the following equation after measuring the twist angles φ1 and φ2 of each TN cell with a general-purpose ellipsometer Optipro manufactured by Shintec Corporation.

Here, Aφ is the anchoring energy [J / m 2] in the azimuth direction, k 22 is the torsional elastic constant [N] of the used liquid crystal material MLC-3007, d is the liquid crystal cell thickness [m], and p is the chiral material S- The chiral pitch [m] of the liquid crystal material MLC-3007 to which 811 is added, φ1 is the liquid crystal twist angle “degree” of the TN cell in which the liquid crystal material MLC-3007 containing no chiral material is encapsulated, and φ2 includes the chiral material S-811 The twist angle [degree] of the TN cell in which the liquid crystal material MLC-3007 is enclosed is shown.

  When the same liquid crystal material is used, the cells can be compared even if the torsional elastic constant k22 is considered as a constant. Therefore, in this embodiment, the anchoring energy Aφ in the azimuth angle direction and the torsional elastic constant k22 of the liquid crystal material are used. The ratio of anchoring energy in the azimuth angle direction was evaluated using the ratio (Aφ / k22).

  On the other hand, even if an alignment film surface having a low pretilt angle and large anchoring energy in the azimuth angle direction can be realized, it goes without saying that it is not worthy of actual use if rubbing streaks or rubbing scratches are generated. Therefore, as a technique for evaluating the likelihood of rubbing streaks and rubbing scratches caused by improper rubbing treatment, a technique for observing the scattering of laser light guided inside the alignment film has been incorporated. Thus, the susceptibility to rubbing muscles and rubbing scratches was evaluated.

  FIG. 6 outlines a method for evaluating rubbing streaks and rubbing scratches caused by laser light scattering. When the alignment treatment is performed uniformly (FIG. 6A), there is almost no light scattering in the optical waveguide, but when the scratches (unevenness) are formed on the alignment film surface by rubbing, or non-uniformity When the degree of stretching of the film surface varies due to rubbing (when the refractive index of the alignment film varies) (FIG. 6B), light scattering increases.

  An aqueous solution containing 20% by weight of titanium dioxide particles having an average particle diameter of 0.6 μm with respect to a 0.02% by weight sodium hydroxide aqueous solution was stirred for 30 minutes with a homogenizer to prepare a titanium dioxide dispersed aqueous solution. Thereafter, the obtained titanium dioxide-dispersed aqueous solution was added to and mixed with a viscose stock solution composed of 9.0% by weight of cellulose and 5.6% by weight of sodium hydroxide to prepare a spinning stock solution.

  The obtained spinning dope is extruded and coagulated and regenerated using a nozzle having a large number of pores in a 40 ° C. bath composed of 60 g / l of sulfuric acid, 350 g / l of sodium sulfate, 15 g / l of zinc sulfate and water. Thereafter, it was washed with water and dried to obtain viscose rayon containing 0.9% by weight of titanium dioxide. FIG. 7 shows a cross-sectional shape photograph.

  Next, the cloth material A for rubbing was produced by weaving the obtained rayon containing titanium dioxide into a ground texture woven with warps and wefts by the following method.

  A warp density of 25 d / cm, a weft density using a 135 dtex (120 denier) long fiber yarn made of cupra fiber as a warp yarn, and a 82 dtex (75 denier) long fiber yarn made of cupra fiber as a weft yarn. A ground texture woven into plain weave at 38 / cm was prepared. Next, as a pile yarn, 135 dtex (120 denier) / 50 filament long fiber yarn made of the obtained titanium dioxide-containing rayon was used, and the yarn density was set to 770 yarns / cm 2 with a known loom as shown in FIG. W-shaped as shown and woven into the ground structure.

  The produced woven fabric was cut so that the number of pile filaments per unit area was 40,000 / cm 2 and the pile length was 1.80 mm. The woven fabric thus woven was made to have the same cut pile height by shearing according to a conventional method, and then a rubbing fabric material A was obtained through a steam process, a washing process, and a raising process.

  Next, a p-type liquid crystal material MLC-3007 (manufactured by Merck & Co., Inc.) was sealed in a homogeneous cell (cell thickness 6.0 μm) subjected to alignment treatment using the rubbing cloth material A, and the pretilt angle was measured. 0.4 degrees. Further, the liquid crystal twist angle measured by sealing MLC-3007 containing no chiral material in a TN cell (cell thickness 5.3 μm) was 87.9 degrees, and MLC-3007 containing the chiral material S-811 (chiral pitch 79. The liquid crystal twist angle measured by enclosing 4 μm) is 89.2 degrees, and the ratio of the anchoring energy Aφ in the azimuth direction calculated from the above formula to the twist elastic constant k22 of the liquid crystal material used is 17.9 / It was μm.

(Comparative Example 1)
A rubbing cloth material X is prepared in exactly the same manner as in Example 1 except that it does not contain titanium dioxide, a test cell is prepared in the same manner, and anchoring energy in the pretilt angle and azimuth directions and twist of the liquid crystal material used. When the ratio of the elastic constant k22 was measured, they were 2.1 degrees and 1.6 / μm, respectively.

  As apparent from the above, the rubbing cloth material of the present invention can provide a low pretilt angle of less than 1 degree and at the same time can provide anchoring energy in a high azimuth direction, and is rubbed for IPS mode (or FFS mode). As a fabric material, its practical value is extremely high.

  An alcohol aqueous solution containing 20% by weight of silicon dioxide particles having an average particle size of 0.1 μm was stirred for 30 minutes with a homogenizer to prepare a silicon dioxide dispersed aqueous solution. Thereafter, the obtained aqueous solution of silicon dioxide dispersion was dissolved in an acetone solution of acetyl acetate, and dry spinning was performed according to a conventional method. The degree of acetylation of the obtained acetate fiber was 2.65, and the solid content concentration of silicon dioxide was 0.4% by weight.

  Thereafter, the obtained acetate fiber containing silicon dioxide was woven into the ground structure in a W-shape as shown in FIG. The prepared woven fabric was cut so that the number of pile filaments per unit area was 40,000 / cm 2 and the pile length was 1.80 mm. The woven fabric thus woven was made into a rubbing cloth material B through a steam process, a cleaning process, and a raised treatment process in the same manner as in Example 1.

  Next, a p-type liquid crystal material MLC-3007 (manufactured by Merck & Co., Inc.) was sealed in a homogeneous cell (cell thickness 6.0 μm) subjected to alignment treatment using the rubbing cloth material B, and a pretilt angle was measured. It was 0.6 degree. In addition, the liquid crystal twist angle measured by enclosing MLC-3007 containing no chiral material in a TN cell (cell thickness 5.5 μm) was 89.5 degrees, and MLC-3007 containing chiral material (chiral pitch 79.4 μm). The liquid crystal twist angle measured after sealing was 91.4 degrees, and the ratio of the anchoring energy Aφ in the azimuth direction calculated from the above formula to the twist elastic constant k22 of the liquid crystal material used was 12.7 / μm. It was.

  As is clear from the above, the rubbing cloth material of the present invention contains inorganic fine particles in the pile yarn, which gives the pile yarn rigidity and can efficiently stretch the alignment film surface, thereby suppressing the liquid crystal pretilt angle. I can do it. Further, it has a feature that the anchoring energy in the azimuth angle direction of the liquid crystal molecules can be increased, and is extremely effective for suppressing burn-in in the IPS mode and the FFS mode.

  The rubbing cloth materials C to J are produced in exactly the same manner as in Example 1 except that the particle diameter of titanium dioxide is different, the test cell is subjected to alignment treatment, and the pretilt angle and the azimuthal anchoring energy of the liquid crystal material The ratio to the liquid crystal twist elastic constant was measured. In addition, the ease with which rubbing streaks and rubbing scratches were generated by the laser light scattering method was also evaluated. The results are shown in Table 1.

As is clear from Table 1, the rubbing cloth material using a pile yarn containing titanium dioxide having a fine particle diameter of 0.1 μm or more and 3.0 μm or less has a low pretilt angle of less than 1 degree and anchoring in a high azimuth direction. Since energy can be realized, it is optimal as a cloth material for rubbing in IPS mode or FFS mode.
When titanium dioxide having a fine particle diameter of 3.5 μm or more is used, it is not preferable because damage to the alignment film surface is large and causes rubbing streaks in the liquid crystal display element. On the other hand, when the fine particle diameter is 0.05 μm or less, the bulk specific gravity becomes small, and workability such as dispersion mixing is remarkably deteriorated.

  In the same manner as in Example 1, titanium dioxide or silicon dioxide having a fine particle diameter of 1.0 μm was dispersed in a viscose stock solution at different dispersion concentrations. Then, it spun in accordance with the conventional method, and it woven into the same ground structure as Example 1, and was set as cloth material K-Q for rubbing.

  Using the obtained rubbing cloth materials K to Q, test cells were subjected to alignment treatment, and the ratio of the pretilt angle and the anchoring energy in the azimuth direction of the liquid crystal material to the liquid crystal twist elastic constant was measured. The results are shown in Table 2. Table 2 also shows the results of observation of the degree of waveguide laser light scattering corresponding to the likelihood of occurrence of rubbing streaks and rubbing scratches.

  As is clear from Table 2, the rubbing fabric using a pile yarn having a fine particle concentration of 0.1% by weight to 4.0% by weight is anchored in a low pretilt angle of less than 1 degree and in a high azimuth direction. Practical value is high, such as being able to realize energy. Further, if the fine particle concentration is 0.05% by weight or less, the effect of adding fine particles is not recognized, and if the fine particle concentration is 5% by weight or more, the possibility of the occurrence of rubbing stripes is increased.

In accordance with a conventional method, SnowTex-20 (trade name of colloidal silica manufactured by Nissan Chemical Industries, Ltd.), polyethylene terephthalate having a silicon dioxide content of 2.5% by weight under the following conditions, full-ultrafine yarn POY135 dtex / 50 The filament was spun. Here, the emulsion concentration was 6% by weight, and the emulsion application amount was 15% by weight.
The spinning conditions were: spin hole orifice diameter (circular): 0.17 mm, number of holes: 50, spinning temperature: 295 ° C., spinning speed: 2600 m / min.

  Thereafter, the obtained polyethylene terephthalate fiber containing silicon dioxide was woven into the ground structure in the W-shape shown in FIG. 1 in the same manner as in Example 1 so that the yarn density was 770 yarns / cm 2. The prepared woven fabric was cut so that the number of pile filaments per unit area was 40,000 / cm 2 and the pile length was 1.80 mm. The woven fabric thus woven was subjected to raising treatment to obtain a rubbing cloth material R.

  Next, the alignment treatment of the test cell was performed using the obtained rubbing cloth material R, and the ratio of the pretilt angle and the azimuthal anchoring energy and the liquid crystal torsional elastic constant of the liquid crystal material was measured. It was 8 degrees and 10.8 / μm.

  As is clear from the above, the rubbing cloth material of the present invention is a rubbing cloth material using pile yarn containing inorganic fine particles, and the pretilt angle of liquid crystal alignment is lowered by using the rubbing cloth material of the present invention. The anchoring energy in the azimuth angle direction can be increased.

  Conventionally, in the case of clothing, fibers with inorganic fine particles dispersed and spun in thermoplastic polymers for the purpose of matting have been known, but the use of these fabrics as rubbing fabrics has different purposes and is easily recalled. It is not possible.

  In the development of a conventional rubbing cloth material, it has been considered that the surface of the alignment film is strongly stretched by increasing the coefficient of friction between the cloth material and the alignment film, thereby imparting a large liquid crystal alignment ability to the alignment film. However, since most of the large frictional force is consumed as heat and is not necessarily used for stretching the alignment film, the friction coefficient and the liquid crystal alignment ability of the alignment film do not correspond to 1: 1. Since fine particles such as titanium oxide also function as a lubricant, rubbing with pile yarns containing fine particles causes less energy loss due to heat and efficiently uses the energy to stretch the alignment film, making it stronger than before. It is considered to be rubbed. That is, the pretilt angle can be further reduced.

  In addition, since the rubbing cloth material using the pile yarn containing fine particles is more rigid than the rubbing cloth material using the pile yarn not containing fine particles, the alignment film is stronger when rubbing the alignment film surface. In order to press the surface polymer chain, it seems that the polymer side chain is inclined more in the horizontal direction to the substrate surface. Therefore, the liquid crystal molecules and the polar part of the alignment film main chain can be brought closer to each other, and the anchoring energy is considered to be increased.

  The materials of the inorganic fine particles, the pile yarn, and the ground texture are not limited to the materials disclosed in the examples of the present invention. Examples of the texture of the rubbing cloth material according to the present invention include recycled fibers represented by rayon, natural fibers represented by cotton, semi-synthetic fibers such as acetate, polyester-based synthetic fibers represented by polyethylene terephthalate, and nylon. A thin or thick fabric using a typical aliphatic polyamide synthetic fiber or a mixed fiber thereof can be used. The fabric structure is not particularly limited as long as the pile yarn can be woven, but a structure as shown in FIG. 1 or 2 is preferably used.

  In the case of long fiber yarns, the warp and weft yarns used in the ground structure are preferably in the range of 33 to 167 dtex (30 to 150 denier). As long fiber yarns, for example, viscose rayon yarn and cupra yarn are used. In the case of a spun yarn, the warp and weft yarns preferably have a cotton count of 140 double yarns to 10 single yarns.

  Suitable inorganic fine particles include zinc sulfide, aluminum oxide, ruthenium oxide, magnesium oxide, titanium dioxide, silicon dioxide, aluminum silicate, barium sulfate, alumina, kaolin, calcium carbonate, sodium carbonate, calcium sulfate, and carbon nanotube. Material. Among these, titanium dioxide and silicon dioxide are more suitable materials because they can be easily obtained with high purity and homogeneity.

  Pile materials used in the present invention include polylactones such as poly (pivalolactone), poly (caprolactone) and homologous polymers; polyurethane; polycarbonate; polysulfone; polyether; polyketone; polyamide such as aliphatic polyamide and aromatic polyamide. Poly (ethylene azelate), poly (ethylene 1,5-naphthalate), poly (1,4-cyclohexanedimethylene terephthalate), poly (ethylene oxybenzoate), poly (p-hydroxybenzoate), poly (1,4 -Cyclohexylidene dimethylene terephthalate), polyethylene terephthalate, polybutylene terephthalate and homologous polymers such as polyesters; polyarylene oxides; polyarylene sulfides; polyetherimides; Polymers and copolymers thereof; ethylene-vinyl acetate copolymers and homologous polymers; acrylic polymers, polyacrylates and copolymers thereof; ethylene-acrylic acid copolymers, ethylene-vinyl alcohol copolymers , Acrylonitrile copolymer, methyl methacrylate-styrene copolymer, ethylene-ethyl acrylate copolymer, methacrylate-butadiene-styrene copolymer, ABS and homologous polymers; low density polyethylene, polypropylene, low density chlorination Polyethylene, poly (4-methyl-1-pentene), polyethylene, polystyrene and homologous polymers; polyfurans; cellulose ester plastics such as cellulose acetate, cellulose acetate butyrate, cellulose propionate and homologous polymers; silicone resins, etc. Can be mentioned. Among these, viscose rayon, polyester, and acetate resin are widely used in clothing, and their manufacturing methods are established, and are particularly suitable for pile yarns.

  In the embodiment of the present invention, the cut pile length is unified to 1.8 mm and the filament density is 40,000 pieces / cm 2, but this does not limit the present invention.

11, 21 Ground warp 12, 22 Ground weft 13, 23 Pile yarn 31, 41, 51 Liquid crystal molecules 32, 42, 62 Alignment film 33, 43 Electrode 34, 44, 63 Glass substrate 52 Alignment film polymer chain 61 Laser light 71 Fine particles of titanium dioxide 72 Rayon

Claims (7)

In a rubbing cloth material comprising a ground structure woven by warps and wefts and a large number of pile yarns woven into the ground structure and protruding from the ground structure, the pile thread contains inorganic fine particles. Rubbing fabric. The rubbing cloth material according to claim 1, wherein the pile yarn is a cut pile yarn made of viscose rayon fiber. The cloth material for rubbing according to claim 1, wherein the pile yarn is a cut pile yarn made of acetate fiber or polyethylene terephthalate fiber. The rubbing cloth material according to any one of claims 1 to 3, wherein the inorganic fine particles are titanium dioxide fine particles. The rubbing cloth material according to any one of claims 1 to 3, wherein the inorganic fine particles are silicon dioxide fine particles. The rubbing cloth material according to any one of claims 1 to 5, wherein a ratio of the inorganic fine particles contained in the pile yarn is 0.1 wt% or more and 4.0 wt% or less. The rubbing cloth material according to any one of claims 1 to 6, wherein the particle size of the inorganic fine particles is 0.1 µm or more and 3.0 µm or less.