JP2009294544A - Method for manufacturing liquid crystal device, and liquid crystal device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a liquid crystal device, in which a liquid crystal device having good contrast characteristics and preventing generation of disclination or the like is obtained and the manufacturing process is further simplified. <P>SOLUTION: The method includes steps of: forming a polymer film in a vertical alignment region A1, the film containing a Si skeleton having a random atomic structure containing a siloxane bond (Si-O), and containing a leaving group coupled to the Si skeleton; allowing the leaving group to leave from the Si skeleton by adding energy to the polymer film; forming long-chain alkyl chains on the surface of the polymer film to obtain a vertical alignment layer 41; forming short-chain alkyl chains in a horizontal alignment region A2 to obtain a horizontal alignment layer 42; and rubbing the surface in one direction where the long-chain alkyl chains and the short-chain alkyl chains are formed. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a method for manufacturing a liquid crystal device and a liquid crystal device.

  There is a liquid crystal projector as a device for displaying an image on a large screen using a liquid crystal device. Projectors are required to have high brightness and high contrast, and in that respect, a vertical alignment type liquid crystal device is capable of high-contrast display, and has recently been adopted as a liquid crystal alignment method in liquid crystal devices for projectors.

  However, in the vertical alignment type liquid crystal device, the liquid crystal stands perpendicular to the substrate surface, and the interaction in the azimuth direction that falls when a voltage is applied is weak. Further, when a pixel potential is applied, a horizontal electric field is generated from the end of the pixel electrode, and the liquid crystal is tilted in various directions due to the horizontal electric field, thereby causing disclination.

  Such disclination is visually recognized as display defects such as unevenness of brightness and darkness, a decrease in contrast, and an afterimage. Therefore, it is necessary to prevent the occurrence thereof. Therefore, liquid crystal is aligned vertically in the pixel area to ensure good contrast characteristics, while liquid crystal is horizontally aligned in the non-display area around the pixel area to regulate the alignment of the liquid crystal and generate disclination. A method for preventing the above has been proposed (see, for example, Patent Documents 1 and 2).

  Specifically, in the liquid crystal device disclosed in Patent Document 1, an inorganic alignment film is formed by oblique vapor deposition, and the thickness of the inorganic alignment film is changed to control the alignment angle of the inorganic alignment film, thereby liquid crystal on the alignment film. The azimuth angle is controlled.

In addition, in the liquid crystal device disclosed in Patent Document 2, the vertical alignment restriction region is provided in the pixel region and the horizontal alignment restriction region is provided outside the pixel region, so that the liquid crystal molecules inside the pixel are made uniform when a voltage is applied. Oriented in the direction.
JP 2005-107373 A JP 2001-343651 A

  However, in the above invention, in order to form an oblique vapor deposition layer having a different thickness, two vacuum processes are required, and the process burden increases, so it is difficult to say that the production efficiency and cost are excellent. . In addition, “the pretilt angle of the pixel display area is smaller than the surrounding pretilt angle”, and the vertical direction with respect to the substrate plane is not strongly regulated, so it is said that the contrast is excellent. hard. In Patent Document 2, UV light is irradiated to the vertical alignment film in order to form a horizontal alignment regulating region outside the pixel region. However, the cut alkyl group remains and burns in. May cause problems.

  The present invention has been proposed in view of such conventional circumstances, and provides a liquid crystal device that has good contrast characteristics and prevents the occurrence of disclination and the like, and further improves the manufacturing process. It is an object to provide a method for manufacturing a liquid crystal device that can be simplified.

  In order to achieve the above object, a method of manufacturing a liquid crystal device according to the present invention includes a first substrate having a plurality of pixel electrodes, a second substrate disposed opposite to the first substrate, a first substrate, A liquid crystal layer sandwiched between the two substrates, and vertically aligns the liquid crystal molecules of the liquid crystal layer in a portion corresponding to the display region of the plurality of pixel electrodes on at least the surface of the first substrate facing the liquid crystal layer And a horizontal alignment film that horizontally aligns liquid crystal molecules in a liquid crystal layer in a portion corresponding to a non-display area between the display areas. Si skeleton having a random atomic structure including a siloxane bond (Si—O) in a portion corresponding to a display region when a vertical alignment film and a horizontal alignment film are formed on the surface of the substrate facing the liquid crystal layer. And debonding bonded to this Si skeleton. Forming a polymer film including a group, applying energy to the polymer film to remove the leaving group from the Si skeleton, and forming a long alkyl chain on the surface of the polymer film to form a vertical alignment film; A step of forming a long alkyl chain, forming a short alkyl chain in a non-display region to form a horizontal alignment film, and a surface on which the long alkyl chain and the short alkyl chain are formed in a fixed orientation. And a rubbing process in the direction.

  In the method for manufacturing a liquid crystal device according to the present invention, when the vertical alignment film and the horizontal alignment film are formed on the surface of the first substrate facing the liquid crystal layer, a plurality of pixel electrodes can be displayed without using a resist or the like. A vertical alignment film in which a long chain alkyl chain is bonded to a portion corresponding to a region via a polymer film, and a horizontal alignment film in which a short chain alkyl chain is bonded to a portion corresponding to a non-display region existing between display regions Can be formed with high accuracy. Further, since no resist or the like is used, the manufacturing process can be simplified.

  In the liquid crystal device manufactured by the method of the present invention, when no voltage is applied, the liquid crystal molecules in the liquid crystal layer are vertically aligned by long-chain alkyl chains (vertical alignment films) formed in portions corresponding to the display regions of the plurality of pixel electrodes. By aligning, the short-chain alkyl chain (horizontal alignment film) formed in the portion corresponding to the non-display area existing between the display areas ensures a good contrast characteristic, and the liquid crystal molecules of the liquid crystal layer are oriented in a certain direction. By horizontally aligning in the direction, it is possible to prevent the occurrence of disclination and the like because the liquid crystal molecules in the liquid crystal layer are aligned in a certain azimuth direction while suppressing the influence of the lateral electric field when a voltage is applied.

  Further, in the method for manufacturing a liquid crystal device according to the present invention, when the energy for releasing the leaving group from the Si skeleton is applied to the polymerized film, the surface facing the liquid crystal layer of the first substrate using a photomask is used. Light that imparts the energy can be selectively irradiated.

  In this case, a vertical alignment film in which a long-chain alkyl chain is bonded to a portion corresponding to the display region of a plurality of pixel electrodes via a polymer film, and a short chain in a portion corresponding to the non-display region existing between the display regions. A horizontal alignment film to which an alkyl chain is bonded can be formed with high accuracy.

  In the method for manufacturing a liquid crystal device according to the present invention, when the polymer film is provided with energy for releasing the leaving group from the Si skeleton, the pixel electrode is provided on the surface of the first substrate facing the liquid crystal layer. A light-shielding film that shields a portion corresponding to the non-display area is provided before formation, and light for applying the energy can be irradiated from the surface opposite to the surface facing the liquid crystal layer of the first substrate. .

  In this case, the self-alignment using the light-shielding film as a mask exists between the display region and the vertical alignment film in which the long-chain alkyl chain is bonded to the portion corresponding to the display region of the plurality of pixel electrodes via the polymer film. A horizontal alignment film in which a short alkyl chain is bonded to a portion corresponding to the non-display area can be formed with high accuracy.

  In the method for producing a liquid crystal device according to the present invention, a long chain alkyl chain is formed by reacting a silane coupling agent containing a long chain alkyl group by a gas phase treatment, and the short chain alkyl chain is formed by a short chain alkyl group. It is preferable to form by reacting a silane coupling agent containing

  Thereby, a long-chain alkyl chain and a short-chain alkyl chain can be appropriately formed in the display region and the non-display region, respectively.

  In the method for manufacturing a liquid crystal device according to the present invention, it is preferable that the number of carbon atoms in the long chain alkyl chain is 11 to 20 and the number of carbon atoms in the short chain alkyl chain is 5 to 10.

  Thereby, a long-chain alkyl chain having a length suitable for the vertical alignment film and a short-chain alkyl chain having a length suitable for the horizontal alignment film can be appropriately formed.

  The liquid crystal device according to the present invention is sandwiched between a first substrate having a plurality of pixel electrodes, a second substrate disposed opposite to the first substrate, and the first substrate and the second substrate. A vertical alignment film that vertically aligns liquid crystal molecules of the liquid crystal layer in a portion corresponding to the display region of the plurality of pixel electrodes on at least a surface of the first substrate facing the liquid crystal layer; A liquid crystal device having a horizontal alignment film for horizontally aligning liquid crystal molecules of a liquid crystal layer in a certain azimuth direction in a portion corresponding to a non-display area existing between the vertical alignment films corresponding to the display area of the pixel electrode The horizontal alignment film is mainly formed of short-chain alkyl chains that are bonded to the non-display area while the long-chain alkyl chains are formed. It is characterized by being.

  In the liquid crystal device according to the present invention, the long alkyl chain (vertical alignment film) formed in the portion corresponding to the display area of the plurality of pixel electrodes vertically aligns the liquid crystal molecules of the liquid crystal layer, thereby providing good contrast characteristics. A short-chain alkyl chain (horizontal alignment film) formed in the portion corresponding to the non-display area existing between the display areas while ensuring the voltage application by horizontally aligning the liquid crystal molecules of the liquid crystal layer in a certain azimuth direction Occasionally, the influence of the lateral electric field is suppressed, and the liquid crystal molecules in the liquid crystal layer are aligned in a certain azimuth direction, so that the occurrence of disclination can be prevented.

  In the liquid crystal device according to the present invention, the polymer film preferably includes a Si skeleton including a siloxane bond (Si—O) and having a random atomic structure.

  Thereby, it can be set as the structure where the long-chain alkyl chain was firmly couple | bonded through the polymer film to the part corresponding to the display area of a some pixel electrode.

Hereinafter, a manufacturing method of a liquid crystal device to which the present invention is applied will be described in detail with reference to the drawings.
In addition, in the drawings used in the following description, in order to make the features easy to understand, there are cases where the portions that become the features are enlarged for the sake of convenience, and the dimensional ratios of the respective components are not always the same as the actual ones. Absent.

[Liquid Crystal Device]
First, a liquid crystal device 1 shown in FIG. 1 will be described as an embodiment of the present invention.
As shown in FIG. 1, the liquid crystal device 1 includes an active matrix type liquid crystal panel 58 using TFT (Thin-Film Transistor) elements. The liquid crystal panel 58 includes a first substrate 10, a second substrate 20 disposed to face the first substrate 10, and a liquid crystal layer 50 sandwiched between the first substrate 10 and the second substrate 20. It is composed of

  The first substrate 10 includes a transparent substrate body 10A such as glass, a light shielding film 13 formed on the substrate body 10A, an interlayer insulating layer 14 formed so as to cover the light shielding film 13, and this interlayer insulation. A plurality of pixel electrodes 9 formed on the layer 14 and a first alignment film 11 formed so as to cover the plurality of pixel electrodes 9 are formed. Further, on the light shielding film 13, a TFT element (not shown) as a switching element, various wirings (not shown), and the like are formed.

  As shown in FIG. 2, the first substrate 10 corresponds to a plurality of pixel electrodes 9 arranged in a matrix in the plane (the outer peripheral portion is 9a and the peripheral portion is 9b). The pixel area (display area) P provided on the inner side and a light shielding area (non-display area) BM that shields light between the pixel areas P are configured.

  The pixel electrode 9 is made of a transparent conductive film such as ITO (indium tin oxide). The light shielding film 13 is made of, for example, a light shielding material such as Cr, and shields the G between the pixel electrodes 9 and the peripheral portion 9b. Therefore, the light incident from the substrate body 10A side is transmitted through the pixel region P as a pixel opening section partitioned by the light shielding region BM.

  As shown in FIG. 1, the first alignment film 11 includes a vertical alignment film 41 that vertically aligns the liquid crystal molecules 51 of the liquid crystal layer 50 in portions corresponding to the pixel regions P of the plurality of pixel electrodes 9, and a light shielding region BM. In a corresponding portion, the liquid crystal layer 50 includes a horizontal alignment film 42 that horizontally aligns the liquid crystal molecules 52 in a certain azimuth direction. Thereby, as shown in FIG. 2, the vertical alignment region A1 including at least the entire pixel region P is formed in the surface of the first substrate 10, and the vertical alignment region A1 corresponds to the light shielding region BM. A horizontal alignment region A2 is formed so as to surround. Further, in the first substrate 10, as shown in FIG. 1, when the width of the light shielding region BM is a, the width of the horizontal alignment region A2 is b, and the width of the G between the pixel electrodes 9 is c, these relationships are a > B> c. Thus, the width (b) of the horizontal alignment region A2 is set larger than the width (c) of the G between the pixel electrodes 9, and the horizontal alignment film 42 is formed on the peripheral edge 9b of the pixel electrode 9. Some are arranged. In the first substrate 10, the width (a) of the light shielding region BM and the width (b) of the horizontal alignment region A2 may be equal.

  On the other hand, as shown in FIG. 1, the second substrate 20 includes a transparent substrate body 20A made of glass or the like, a common electrode 21 formed on the substrate body 20A, and a second alignment film made of a vertical alignment film. 22. The common electrode 21 and the second alignment film 22 are provided over at least the entire display region on the second substrate 20 side without being partitioned for each pixel region P.

  The liquid crystal layer 50 is formed by sandwiching a liquid crystal having negative dielectric anisotropy between the first alignment film 11 of the first substrate 10 and the second alignment film 22 of the second substrate 20. Has been. Moreover, the edge part of the 1st board | substrate 10 and the 2nd board | substrate 20 which are mutually opposingly arranged is sealed with the sealing material (not shown).

  The liquid crystal device includes a pair of quarter-wave plates 81 and 82 disposed on both sides of the liquid crystal panel 58 and a pair of polarizing plates 71 disposed outside the pair of quarter-wave plates 81 and 82. , 72. Specifically, on the outside of the first substrate 10 and the second substrate 20, quarter-wave plates 81 and 82 are arranged so that their optical axes are orthogonal to each other. Further, the polarizing plates 71 and 72 form an angle of about 45 ° with respect to the optical axes of the quarter-wave plates 81 and 82 having the polarization axes arranged inside, and the polarization axes are orthogonal to each other. Are arranged to be. A light source unit (not shown) is disposed below the polarizing plate 71.

  By the way, out of the vertical alignment film 41 and the horizontal alignment film 42 constituting the first alignment film 11, the vertical alignment film 41 has a polymer film 43 on the surface of the pixel electrode 9 corresponding to the vertical alignment region A1. Is formed. The polymer film 43 includes a Si skeleton including a siloxane bond (Si—O) and a random atomic structure. Before the long-chain alkyl chain 28A of the vertical alignment film 41 described later is bonded, a siloxane bond ( It has a Si skeleton having a random atomic structure including Si—O) and a leaving group bonded to the Si skeleton. Such a polymerized film 43 exhibits adhesiveness by detaching the leaving group from the Si skeleton, and has a function of firmly bonding the vertical alignment film 41 to the surface of the pixel electrode 9.

  As schematically shown in FIG. 3, the vertical alignment film 41 is mainly composed of a long-chain alkyl chain 28A having 11 to 20 carbon atoms, and the long-chain alkyl chain 28A includes a long-chain alkyl group. It is formed by chemically modifying the surface of the pixel electrode 9 corresponding to the vertical alignment region A1 (the polymer film 43 is omitted in FIG. 3) using a silane coupling agent. The long alkyl chain 28A is bonded in a state where the straight chain stands up substantially perpendicular to the substrate surface, thereby having a vertical alignment ability.

  On the other hand, the horizontal alignment film 42 is mainly composed of a short-chain alkyl chain 28B having 5 to 10 carbon atoms, and this short-chain alkyl chain 28B uses a silane coupling agent containing a short-chain alkyl group, The peripheral edge 9b of the pixel electrode 9 corresponding to the horizontal alignment region A2 and the exposed surface of the interlayer insulating layer 14 are chemically modified. The short alkyl chain 28B is in a state in which the straight chain is tilted in one direction with respect to the substrate surface (the direction of the substrate), whereby the horizontal alignment ability (alignment regulation in one direction). Power).

  In addition, the pretilt angle at which the liquid crystal molecules 52 of the liquid crystal layer 50 are aligned by the horizontal alignment film 42 is preferably 1 ° to 20 ° with respect to the substrate surface, and more preferably 10 ° or less. As a result, it is possible to obtain an alignment regulating force that can suppress the influence of the lateral electric field generated when a voltage is applied.

  Similar to the vertical alignment film 41, the second alignment film 22 is mainly composed of a long-chain alkyl chain 28A having 11 to 20 carbon atoms. The long-chain alkyl chain 28A has a long-chain alkyl group. It is formed by chemically modifying the surface of the common electrode 21 using a silane coupling agent containing. The long alkyl chain 28A is bonded in a state where the straight chain stands up substantially perpendicular to the substrate surface, thereby having a vertical alignment ability.

  In the liquid crystal device having the above-described structure, the vertical alignment film 41 (long chain) formed in a portion (vertical alignment region A1) corresponding to the pixel region P in the initial alignment state (no voltage applied state) shown in FIG. The alkyl chain 28A) vertically aligns the liquid crystal molecules 51 of the liquid crystal layer 50, thereby securing a good contrast characteristic and a horizontal alignment film 42 (formed in the portion corresponding to the light shielding region BM (horizontal alignment region A2)) ( The short alkyl chain 28B) horizontally aligns the liquid crystal molecules 52 of the liquid crystal layer 50 in a fixed azimuth direction.

  Then, when a voltage is applied between the pixel electrode 9 and the common electrode 21, as shown in FIG. 4, the liquid crystal molecules 51 positioned on the vertical alignment region A1 (vertical alignment film 41) are formed on the substrate according to the voltage. Tilt from the normal direction. As a result, the light transmitted in the thickness direction of the liquid crystal panel 58 is modulated to enable gradation display. Note that the liquid crystal molecules 51 of the liquid crystal 50 that are vertically aligned on the pixel electrode 9 are affected by the lateral electric field generated from the end of the pixel electrode 9 when there is no means for regulating the tilting direction. In response, it tends to fall radially toward the inside of the pixel electrode 9. However, since the alignment directions of the liquid crystal molecules 51 oppose each other at the center of the pixel electrode 9, the liquid crystal molecules 51 near the center of the pixel electrode 9 cannot fall down, causing disclination while being vertically aligned. .

  In the present invention, the liquid crystal molecules 51 located in the vicinity of the horizontal alignment region A2 of the vertical alignment region A1 are greatly affected by the alignment of the liquid crystal molecules 52 on the peripheral edge portion 9b of the pixel electrode 9. Accordingly, the liquid crystal molecules 51 on the vertical alignment region A1 are tilted in a uniform direction when a voltage is applied, and are uniformly aligned. As a result, even if a lateral electric field is generated in the direction parallel to the first substrate 10 from the end of the pixel electrode 9 toward the common electrode 21, the influence of the lateral electric field is suppressed and the liquid crystal molecules 51 are not aligned. It is possible to prevent the occurrence of disclination due to the above.

  Since the liquid crystal molecules 52 on the peripheral edge 9b of the pixel electrode 9 are located in the light shielding region BM, they do not contribute to the transmittance of the pixel region P, and the transmittance of the pixel region P is above the vertical alignment region A1. It depends only on the liquid crystal molecules 51 located in Therefore, no light leaks from the pixel region P when no voltage is applied.

[Method of manufacturing liquid crystal device]
Next, the manufacturing process of the liquid crystal panel 58 manufactured by applying the present invention will be described.
In addition, the material etc. which are illustrated in the following description are examples, Comprising: This invention is not necessarily limited to them, It can change suitably in the range which does not change the summary.

The liquid crystal panel 58 includes a step of manufacturing the first substrate 10, a step of manufacturing the second substrate 20 in parallel with or before or after this step, and the manufactured first substrate 10 and second substrate. And a step of forming a liquid crystal layer 50 having a predetermined thickness by injecting a liquid crystal having a negative dielectric anisotropy into a space therebetween.
(First substrate manufacturing process)
As for the manufacturing process of the first substrate 10, first, as shown in FIG. 5, a light shielding film 13 made of Cr (chromium) is formed in a lattice shape on a substrate body 10 </ b> A made of glass. BM is defined, and a region surrounded by the light shielding region BM is defined as a pixel region P. Subsequently, although not shown, wiring such as TFT elements, data lines, and scanning lines is formed on the light shielding film 13, and the interlayer insulating layer 14 is formed so as to cover them. Subsequently, a plurality of pixel electrodes 9 made of ITO (Indium Tin Oxide) are arranged in a matrix on the surface flattened by the interlayer insulating layer 14 so as to protrude from the pixel region P toward the light shielding region BM. Form. In addition, there is no restriction | limiting in particular in these processes, A well-known method can be used.

  Next, as shown in FIG. 6, a polymer film 43 is formed in the vertical alignment region A1. Specifically, a mask (not shown) having an opening in a portion corresponding to the vertical alignment region A1 is disposed on the surface of the first substrate 10 on which the pixel electrode 9 is formed, and a plasma polymerization method is performed. The polymerized film 43 is formed while depositing the polymer produced in this way on the vertical alignment region A1. The polymer film 43 may be formed over the entire surface of the first substrate 10 on which the pixel electrode 9 is formed.

  For example, as schematically shown in FIG. 16A, the polymer film 43 formed in this way includes a Si skeleton 43a including a siloxane bond (Si—O) and a random atomic structure, and the Si skeleton 43a. And a leaving group 43b to be bonded. The polymer film 43 becomes a solid having no fluidity due to the influence of the Si skeleton 43a including a siloxane bond and having a random atomic structure, and a film having high dimensional accuracy is obtained.

  Moreover, as such a polymer film 43, it is particularly preferable that the total of the Si atom content and the O atom content is 10 to 90 atom% among the atoms obtained by removing H atoms from the constituent atoms. More preferably, it is 20-80 atomic%. As a result, in the polymerized film 43, Si atoms and O atoms form a strong network, and the film itself becomes strong. Further, a long-chain alkyl chain 28A of the vertical alignment film 41 described later can be firmly bonded.

  Examples of the leaving group 43b include an alkyl group such as a methyl group and an ethyl group, an alkenyl group such as a vinyl group and an allyl group, an aldehyde group, a ketone group, a carboxyl group, an amino group, an amide group, a nitro group, and a halogen. Alkyl group, mercapto group, sulfonic acid group, cyano group, isocyanate group and the like. Of these, the leaving group 43b is particularly preferably an alkyl group. Since the alkyl group has high chemical stability, the polymer film 43 containing the alkyl group as the leaving group 43b has excellent weather resistance and chemical resistance.

  Specific examples of the constituent material of the polymer film 43 include a polymer combined with a siloxane bond such as polyorganosiloxane. The polymer film 43 made of polyorganosiloxane itself has excellent mechanical properties. In addition, it exhibits particularly excellent adhesion to many materials. Polyorganosiloxane usually exhibits water repellency (non-adhesiveness) due to the action of an alkyl group, but when it is given energy, it desorbs an organic group and changes its hydrophilicity, thereby exhibiting adhesiveness. The non-adhesiveness and adhesiveness can be controlled easily and reliably.

  In addition, among the polyorganosiloxanes, the polymer film 43 mainly composed of octamethyltrisiloxane is excellent in adhesiveness. Moreover, since the raw material which has octamethyltrisiloxane as a main component is liquid at normal temperature and has an appropriate viscosity, there is also an advantage that it can be easily attached.

  As a method for forming the polymer film 43, the above-described plasma polymerization method is suitable for efficiently forming a dense and uniform polymer film 43. In addition, since the polymer film 43 formed by the plasma polymerization method is kept activated for a relatively long time by applying energy, the manufacturing process can be simplified and improved in efficiency. it can. The film formation method of the polymer film 43 is not limited to such a plasma polymerization method, and various vapor phase film formation methods such as a CVD method and a PVD method, and various liquid phase film formation methods may be used. it can.

  The average thickness of the polymer film 43 is preferably 1-1000 nm, more preferably 2-800 nm. Thereby, the long-chain alkyl chain 28A of the vertical alignment film 41 to be described later can be firmly bonded while preventing the dimensional accuracy from being significantly lowered.

  Next, as shown in FIG. 7, energy is applied to the polymer film 43 to desorb the leaving group 43b from the Si skeleton 43a. As schematically shown in FIG. 16B, the polymer film 43 is provided with such energy, and when the leaving group 43b is detached from the Si skeleton 43a, active hands 43c are generated on the surface or inside thereof. Activated. Thereby, adhesiveness is developed on the surface of the polymer film 43.

  Here, “activate” the polymerized film 43 means that the surface of the polymerized film 43 or the leaving group 43b on the inside of the polymerized film 43 is detached, and a bond not terminated in the Si skeleton 43a (hereinafter referred to as “unbonded hand”). Or “dangling bond”) refers to a state where 43c is generated, a state where this dangling bond is terminated by a hydroxyl group (OH group), or a state where these states are mixed. The active hand 43a refers to an unbonded hand (dangling bond) or an unbonded hand terminated by a hydroxyl group (OH group), and the presence of such an active hand 43a causes the surface of the polymer film 43 to be activated. Adhesiveness will be developed.

  Here, the energy applied to the polymer film 43 is, for example, a method of irradiating energy rays, a method of heating the polymer film 43, a method of applying a compressive force (physical energy) to the polymer film 43, or exposure to plasma ( The method of applying plasma energy), the method of exposing to ozone gas (applying chemical energy), and the like can be mentioned. Among them, the method of irradiating energy rays is relatively simple and efficiently applying energy. Suitable because it can.

  Examples of energy rays include ultraviolet rays, laser beams, X-rays, γ-rays, electron beams, particle beams such as ion beams, or combinations thereof, among which, in particular, the wavelength is 150. It is preferable to use an ultraviolet ray of ˜300 nm, more preferably 160 to 200 nm. When such ultraviolet rays are used, the amount of energy applied to the polymer film 43 is optimized, and the Si skeleton 43a and the leaving group 43b are prevented from being destroyed more than necessary. The bond between can be selectively broken. Thereby, adhesiveness can be expressed in the polymer film 43 while preventing the characteristics (mechanical characteristics, chemical characteristics, etc.) of the polymer film 43 from deteriorating.

In addition, since ultraviolet rays can be processed over a wide range in a short time without unevenness, the leaving group 43b can be efficiently removed. Furthermore, ultraviolet rays also have the advantage that they can be generated with simple equipment such as UV lamps. In the case of using a UV lamp, although different depending on the area of the polymerization film 43, it is preferable to set the output ^{1mW / cm 2 ~1W / cm 2} . Further, the distance between the UV lamp and the polymer film 43 is preferably 3 to 3000 mm, more preferably 10 to 1000 mm.

  In addition, the time for irradiating the ultraviolet rays is set to a time that allows the leaving groups 43b near the surface of the polymer film 43 to be released, that is, a time that does not allow a large amount of the leaving groups 43b inside the polymer film 43 to be released. Is preferred. Specifically, it is preferably 0.5 to 30 minutes, more preferably 1 to 10 minutes, although it varies slightly depending on the amount of ultraviolet light, the constituent material of the polymer film 43, and the like. Further, the ultraviolet light may be irradiated continuously in time or intermittently (pulsed).

On the other hand, examples of the laser light include an excimer laser (femtosecond laser), an Nd—YAG laser, an Ar laser, a CO ₂ laser, and a He—Ne laser.

  Moreover, the irradiation of the energy beam to the polymer film 43 is not particularly limited in the atmosphere at the time of the irradiation. For example, the atmosphere, an oxidizing gas atmosphere containing oxygen, or a reducing gas atmosphere containing hydrogen An inert gas atmosphere such as nitrogen or argon, or a reduced pressure (vacuum) atmosphere obtained by reducing these atmospheres. Among these, it is preferable to irradiate energy rays in an air atmosphere. This eliminates the need for labor and cost for controlling the atmosphere and simplifies the process.

  In the present embodiment, as shown in FIG. 7, an excimer having a wavelength of 172 nm from the surface facing the liquid crystal layer 50 of the first substrate 10 using a photomask M having an opening in a portion corresponding to the vertical alignment region A1. Irradiation with ultraviolet light (UV light) by a laser is performed to remove a leaving group (for example, methyl group) 43b from the Si skeleton 43a. Thereby, active hands 43a are generated on the surface of the polymerized film 43, and adhesiveness is developed.

  Next, as shown in FIG. 8, the activated surface of the polymer film 43 is reacted with a silane coupling agent having a long chain alkyl group by a gas phase treatment to form the long chain alkyl to be the vertical alignment film 41. Group 28A is formed.

  The long-chain alkyl group 28A is left in a sealed container together with a container having a silane coupling agent having a long-chain alkyl group having 11 to 20 carbon atoms, and the vapor of the silane coupling agent is heated to the substrate while the container is heated. By contacting the surface of the main body 10 </ b> A on which the pixel electrode 9 is formed, it is selectively bonded to the activated surface of the polymerized film 43.

  Here, the silane coupling agent has an organic functional group and a hydrolyzable group in one molecule, thereby linking the inorganic substance and the organic substance, and improving the physical strength, durability, adhesion, etc. of the material. Is possible. Specifically, a silicon atom (Si) has one organic functional group and a functional group that reacts with a few inorganic substances, and is represented by the following formula.

The silane coupling agent to be used is not particularly limited as long as the organic functional group has good water repellency and good light resistance. Specifically, the organic functional group in the compound formula What (Y) is an alkyl group is used suitably. Although there is no particular limitation on hydrolyzable group, such as methoxy group _(-O-CH 3), an ethoxy group _(-O-C 2 _{H 5)} are preferred.

  In this embodiment, as schematically shown in FIG. 9, after activating the surface of the polymer film 43, the substrate body 10 </ b> A has, for example, a silane coupling having a long-chain alkyl group having 18 carbon atoms in the side chain. Together with a container having an agent (ODS: octadecyltriethoxysilane), left in a closed container. Then, the container is allowed to stand for 2 hours while being heated at a temperature of 180 ° C., and the vapor of the silane coupling agent is brought into contact with the surface on which the pixel electrode 9 of the substrate body 10A is formed. Here, the long-chain alkyl group has a silanol group (Si—OH), so that the long-chain alkyl group is firmly bonded to the active hand 43 c of the polymerized film 43. Therefore, the long-chain alkyl group 28A can be formed on the vertical alignment region A1 of the pixel electrode 9 via the polymer film 43.

  Next, as shown in FIG. 10, a horizontal alignment region A2 surrounding the vertical alignment region A1 of the first substrate 10 is reacted with a silane coupling agent having a short-chain alkyl group by a gas phase treatment, so that the horizontal alignment film is formed. A short-chain alkyl group 28B to be 42 is formed.

  The short-chain alkyl group 28B is left in a sealed container together with a container having a silane coupling agent having a short-chain alkyl group having 5 to 10 carbon atoms, and the vapor of the silane coupling agent is heated while the container is heated. By making contact with the surface of the main body 10 </ b> A facing the liquid crystal layer 50, it is selectively coupled to the horizontal alignment region A <b> 2 exposed from between the vertical alignment films 41.

  The short-chain alkyl chain 28B is, for example, a pentyl group (C5), hexyl group (C6), heptyl group (C7), octyl group (C8), nonyl as trimethoxysilane having an alkyl group having 5 to 10 carbon atoms. Examples thereof include a group (C9) and a decyl group (C10).

  In this embodiment, as schematically shown in FIG. 11, after forming the long chain alkyl chain 28 </ b> A to be the vertical alignment film 41, the substrate body 10 </ b> A has, for example, a short chain alkyl group having 6 carbon atoms as a side chain. The container having the silane coupling agent is heated at a temperature of 120 ° C. and left in the sealed container for 2 hours to bring the silane coupling agent vapor into contact with the surface of the substrate body 10A on which the pixel electrodes 9 are formed. . Here, since the short-chain alkyl group has a silanol group (Si—OH), the interlayer insulation exposed between the peripheral edge portion 9b of the pixel electrode exposed between the vertical alignment films 41 and the pixel electrode 9 is used. It is selectively bonded to layer 14. Thereby, the short chain alkyl group 28B can be formed on the horizontal alignment region A2.

  Next, as shown in FIG. 12, the surface on which the long chain alkyl chain 28A and the short chain alkyl chain 28B are formed is rubbed in a fixed azimuth direction using a rubbing treatment device 55 in which a rubbing cloth is wound around a roller. . Here, the short alkyl chain 28B having a short chain length is easy to tilt with respect to the substrate surface, and by performing such rubbing treatment, most of them are uniformly tilted (tilted) along the rubbing direction. Will do. Note that the long chain alkyl group 28A having a long chain length hardly aligns in the horizontal direction even when rubbed, and maintains the vertical alignment state.

  As described above, the first substrate 10 provided with the vertical alignment film 41 in the vertical alignment region A1 and the horizontal alignment film 42 in the horizontal alignment region A2 can be manufactured.

(Second substrate manufacturing process)
Regarding the manufacturing process of the second substrate 20, first, as shown in FIG. 13, a common electrode 21 made of ITO is formed on a substrate body 20A made of a material made of glass, and a long-chain alkyl is formed on the common electrode 21. It is obtained by forming a second alignment film 22 made of a vertical alignment film mainly composed of the chain 28A. A known method can be used for these steps. For example, a vapor deposition method or the like is suitable for forming the common electrode 21.

The second alignment film 22 (vertical alignment film) can be formed using, for example, a silane coupling agent containing a long-chain alkyl group 28A, as with the vertical alignment film 41 described above. In this case, the second alignment film 22 is formed on the common electrode 21 corresponding to the vertical alignment region A1 and the horizontal alignment region A2 on the first substrate 10 side without being divided for each pixel region.
As described above, the second substrate 20 including the second alignment film 22 can be manufactured.

(Board bonding and liquid crystal injection process)
Next, as shown in FIG. 14, the first substrate 10 and the second substrate 20 are bonded so that the first alignment film 11 and the second alignment film 22 are inside, and as shown in FIG. The liquid crystal panel 58 is manufactured by enclosing the liquid crystal layer 50 between the first substrate 10 and the second substrate 20.

  As described above, in the manufacturing method of the present invention, when the vertical alignment film 41 and the horizontal alignment film 42 are formed on the surface of the first substrate 10 facing the liquid crystal layer 50, a plurality of resists are not used. Between the vertical alignment film 41 in which the long chain alkyl chain 28A is bonded to the portion (vertical alignment area A1) corresponding to the pixel area P (display area) of the pixel electrode 9 via the polymer film 43 and the pixel area P. The horizontal alignment film 42 in which the short-chain alkyl chain 28B is bonded to the portion (horizontal alignment region A2) corresponding to a certain light shielding region BM (non-display region) can be formed with high accuracy. Further, since no resist or the like is used, the manufacturing process can be simplified.

  In the liquid crystal panel 58 obtained by such a manufacturing method, the long-chain alkyl chain 28A (vertical alignment film 41) formed in the vertical alignment region A1 via the polymer film 43 causes the liquid crystal molecules 51 of the liquid crystal layer 50 to move. The short-chain alkyl chain 28B (horizontal alignment film 42) formed in the horizontal alignment region A2 horizontally aligns the liquid crystal molecules 52 of the liquid crystal layer 50 in a certain azimuth direction while ensuring good contrast characteristics by performing vertical alignment. As a result, the influence of the lateral electric field during voltage application is suppressed, and the liquid crystal molecules 51 and 52 of the liquid crystal layer 50 are aligned in a fixed azimuth direction, so that the occurrence of disclination can be prevented.

In addition, this invention is not necessarily limited to the thing of the said embodiment, A various change can be added in the range which does not deviate from the meaning of this invention.
For example, in the above embodiment, the light shielding film 13 is provided on the first substrate 10 side. However, the light shielding film 13 may be provided on the second substrate 20 side. Also in this case, the first alignment film 11 includes the vertical alignment film 41 in the portion corresponding to the pixel region P of the plurality of pixel electrodes 9 (vertical alignment region A1) and the portion corresponding to the light shielding region BM (horizontal alignment region A2). ), The light shielding film 13 may be formed on the surface of the second substrate 20 facing the liquid crystal layer 50 so as to surround the pixel region P corresponding to the light shielding region BM. .

  Further, in the manufacturing method of the present invention, in order to desorb the leaving group 43b from the Si skeleton 43a of the polymer film 43, a photomask having an opening in a portion corresponding to the pixel region P (vertical alignment region A1) is used. , A method of selectively irradiating light that activates the surface of the polymer film 43 from the side of the first substrate 10 facing the liquid crystal layer 50 is used, but as shown in FIG. By self-alignment using the light shielding film 13 as a mask, light (VUV) for activating the surface of the polymer film 43 can be irradiated from the surface opposite to the surface facing the liquid crystal layer 50 of the first substrate 10. It is. Also in this case, the vertical alignment film 41 in which the long chain alkyl chain 28A is bonded to the pixel region P (vertical alignment region A1) via the polymer film 43, and the short chain alkyl chain 28B in the light shielding region BM (horizontal alignment region A2). Can be formed with high precision. In this case, the pixel region P and the vertical alignment region A1 substantially coincide with each other, and the light shielding region BM and the horizontal alignment region A2 substantially coincide with each other.

[Electronics]
Next, an example of an electronic apparatus including the liquid crystal device according to the above embodiment will be described.
FIG. 18A is a perspective view showing an example of a mobile phone. In FIG. 18A, reference numeral 500 denotes a mobile phone body, and reference numeral 501 denotes a liquid crystal display unit using the liquid crystal device of the above embodiment.

  FIG. 18B is a perspective view illustrating an example of a portable information processing apparatus such as a word processor or a personal computer. In FIG. 18B, reference numeral 600 denotes an information processing apparatus, reference numeral 601 denotes an input unit such as a keyboard, reference numeral 603 denotes an information processing apparatus body, and reference numeral 602 denotes a liquid crystal display unit using the liquid crystal device of the above embodiment. .

  FIG. 18C is a perspective view illustrating an example of a wristwatch type electronic device. In FIG. 18C, reference numeral 700 denotes a watch body, and reference numeral 701 denotes a liquid crystal display unit using the liquid crystal device of the above embodiment.

  As described above, since the electronic device illustrated in FIG. 18 is obtained by applying the above-described liquid crystal device according to the present invention to the display portion, the display device has high contrast and high display quality.

1 is a cross-sectional view illustrating an example of a liquid crystal device to which the present invention is applied. FIG. 2 is an enlarged plan view showing a main part of a first substrate of the liquid crystal panel shown in FIG. 1. The schematic diagram which shows the structure of a vertical alignment film and a horizontal alignment film. Sectional drawing which shows the orientation state at the time of the voltage application of the liquid crystal panel shown in FIG. Sectional drawing which shows the manufacturing process of the liquid crystal panel shown in FIG. Sectional drawing which shows the manufacturing process of the liquid crystal panel shown in FIG. Sectional drawing which shows the manufacturing process of the liquid crystal panel shown in FIG. Sectional drawing which shows the manufacturing process of the liquid crystal panel shown in FIG. Sectional drawing which shows the manufacturing process of the liquid crystal panel shown in FIG. Sectional drawing which shows the manufacturing process of the liquid crystal panel shown in FIG. Sectional drawing which shows the manufacturing process of the liquid crystal panel shown in FIG. Sectional drawing which shows the manufacturing process of the liquid crystal panel shown in FIG. Sectional drawing which shows the manufacturing process of the liquid crystal panel shown in FIG. Sectional drawing which shows the manufacturing process of the liquid crystal panel shown in FIG. Sectional drawing which shows the manufacturing process of the liquid crystal panel shown in FIG. The schematic diagram which shows the state before (a) detachment | leave from a leaving group from Si skeleton of a polymer film, and (b) the state after detachment | leave. Sectional drawing which shows another manufacturing process of the liquid crystal panel shown in FIG. FIG. 11 is a perspective view illustrating an example of an electronic device including a liquid crystal device to which the invention is applied.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Liquid crystal device, 9 ... Pixel electrode, 10 ... 1st board | substrate, 11 ... 1st alignment film, 13 ... Light shielding film, 20 ... 2nd board | substrate, 21 ... Common electrode, 22 ... second alignment film, 28A ... long chain alkyl chain, 28B ... short chain alkyl chain, 41 ... vertical alignment film, 42 ... horizontal alignment film, 43 ..Polymerized film, 43a ... Si skeleton, 43b ... leaving group, 43c ... active hand, 50 ... liquid crystal layer, P ... pixel region (display region), BM ... light shielding Area (non-display area), A1 ... vertical alignment area, A2 ... horizontal alignment area

Claims (7)

A first substrate having a plurality of pixel electrodes; a second substrate disposed opposite to the first substrate; and a liquid crystal layer sandwiched between the first substrate and the second substrate, and at least A vertical alignment film for vertically aligning liquid crystal molecules of the liquid crystal layer in a portion corresponding to the display region of the plurality of pixel electrodes on a surface of the first substrate facing the liquid crystal layer, and between the display region A method for manufacturing a liquid crystal device having a horizontal alignment film that horizontally aligns liquid crystal molecules of the liquid crystal layer in a certain azimuth direction in a portion corresponding to a non-display region existing,
When forming the vertical alignment film and the horizontal alignment film on the surface of the first substrate facing the liquid crystal layer,
Forming a polymer film including a Si skeleton having a random atomic structure including a siloxane bond (Si—O) and a leaving group bonded to the Si skeleton in a portion corresponding to the display region;
Applying energy to the polymer film to desorb the leaving group from the Si skeleton;
Forming a long-chain alkyl chain on the surface of the polymerized film to form the vertical alignment film;
After forming the long alkyl chain, forming a short alkyl chain in the non-display region to form the horizontal alignment film;
And a step of rubbing the surface on which the long-chain alkyl chain and the short-chain alkyl chain are formed in the predetermined azimuth direction.   When applying energy for detaching the leaving group from the Si skeleton to the polymerized film, a light that gives the energy is selected from the side facing the liquid crystal layer of the first substrate using a photomask. The method of manufacturing a liquid crystal device according to claim 1, wherein the liquid crystal device is irradiated.   When the energy for releasing the leaving group from the Si skeleton is applied to the polymerized film, the non-display is performed before forming the pixel electrode on the surface of the first substrate facing the liquid crystal layer. 2. A light-shielding film that shields a portion corresponding to a region is provided, and light that imparts the energy is irradiated from a surface opposite to a surface facing the liquid crystal layer of the first substrate. A method for producing a liquid crystal device according to claim 1.   The long-chain alkyl chain is formed by reacting a silane coupling agent containing a long-chain alkyl group by gas phase treatment, and the short-chain alkyl chain is formed by reacting a silane coupling agent containing a short-chain alkyl group by gas-phase treatment. The method for producing a liquid crystal device according to claim 1, wherein the liquid crystal device is formed by reaction.   5. The liquid crystal device according to claim 1, wherein the long-chain alkyl chain has 11 to 20 carbon atoms and the short-chain alkyl chain has 5 to 10 carbon atoms. Manufacturing method. A first substrate having a plurality of pixel electrodes; a second substrate disposed opposite to the first substrate; and a liquid crystal layer sandwiched between the first substrate and the second substrate, and at least A vertical alignment film for vertically aligning liquid crystal molecules of the liquid crystal layer in a portion corresponding to the display region of the plurality of pixel electrodes on a surface of the first substrate facing the liquid crystal layer, and between the display region A liquid crystal device having a horizontal alignment film for horizontally aligning liquid crystal molecules of the liquid crystal layer in a certain azimuth direction in a portion corresponding to a non-display region existing,
The vertical alignment film is mainly formed of a long alkyl chain bonded to a portion corresponding to the display area of the pixel electrode through a polymer film,
The liquid crystal device according to claim 1, wherein the horizontal alignment film is mainly formed of a short-chain alkyl chain bonded to a non-display region while the long-chain alkyl chain is formed.   The liquid crystal device according to claim 6, wherein the polymer film includes a Si skeleton including a siloxane bond (Si—O) and having a random atomic structure.

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