JP2015011222A - Method of manufacturing alignment film - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an alignment film manufacturing method which enables effective production of an alignment film having a large alignment area formed thereon using a polymerizable material containing only one type of polymerizable compound as a material of the alignment film.SOLUTION: An alignment film manufacturing method uses a film made of a polymerizable material containing only one type of polymerizable compound which exhibits liquid crystalline properties before and/or after polymerization, and obtains an alignment film by initiating polymerization of the polymerizable material from a partial area of the film and then continuously moving a boundary of the area toward an unpolymerized area at a speed that allows the compound exhibiting the liquid crystalline properties in the film to be aligned.

Description

  The present invention relates to a method for producing an oriented film.

  Conventionally, as a method for uniformly aligning a liquid crystal compound, a method of aligning a compound using an external field such as an electric field or a magnetic field, a so-called rubbing method, oblique deposition method, microgroove method, LB film method, A method has been proposed in which anisotropy is imparted to the surface of the substrate in contact with the liquid crystal compound by a photo-alignment method, etc., so that the substrate itself has an alignment regulating force and this is used to align the liquid crystal compound. . And as a manufacturing method of a liquid crystal display element and an alignment film using a method for uniformly aligning such a liquid crystalline compound, industrially, from the viewpoint of increasing the area, processing time and processing cost. From the standpoint of superiority, a method using a rubbing method (for example, a method of rubbing an alignment film such as polyimide with a velvet cloth made of cotton, rayon or the like) has been generally used.

  However, when an oriented film is manufactured by using a rubbing method, static electricity is easily generated during the treatment process, and various problems have arisen due to the static electricity. For example, foreign matter may adhere to the surface of the orientation film due to the generation of static electricity, or orientation defects may occur, resulting in display defects when the film is used in a display device or the like. Further, when the orientation film is formed by using the rubbing method, there are problems such as generation of dust and scratches during rubbing. Further, in the field of liquid crystal display elements, higher definition has been promoted, and since higher pixel density is required, uniformity of the rubbing process is also required, and alignment using the rubbing method is required. In the case of producing a conductive film, the above problem has been decreasing the production yield. Therefore, in recent years, the advent of a method capable of efficiently producing a large-area oriented film by a method other than the rubbing method is desired.

  On the other hand, as one method for producing an oriented film, Chem. In the paper “Photoinduced Opposite Diffusion of Nematic and Isotropic Monomers during Patterned Photopolymerization” (Non-patent Document 1) of Cornelus F. van Nostrum et al. Described on pages 135 to 145 of Mater (Vol. 10, No. 1). Fills a cell containing two opposed glass slides that have been rubbed with a mixture containing two monomers and exposes a portion of the mixture layer using a grid-like photomask. A method for orienting a polymer in the exposed area is disclosed.

  In addition, a paper by Atsushi Shishido “Light of liquid crystal polymer” described in the proceedings of Polymer Society of Japan (Polymer Preprints, vol.61, No.2, page: ROMBUNNO.1L05) published on September 5, 2012. In “Development of Orientation Control and Soft Matter Mechanics (Non-Patent Document 2)”, 4- (6-acryloyloxyhexyloxy) -4′-cyanobiphenyl (A6CB) or 4-acryloyloxy-4′-cyanobiphenyl (A0CB) ) And ethylene glycol dimethacrylate as a monomer are introduced into a cell, and a photomask is applied to irradiate light to perform photopolymerization, whereby a film having optical anisotropy at the boundary portion of the photomask Is disclosed.

Cornelus F. van Nostrum et al. Chem. Mater. , “Photoinduced Opposite Diffusion of Nematic and Isotropic Monomers during Patterned Photopolymerization”, Vol. 10, No. 1, 1998, pages 135-145 Atsushi Shishido, “Control of Photo-Orientation of Liquid Crystalline Polymers and Development of Soft Matter Mechanics”, Proceedings of Polymer Society (Polymer Preprints: CD-ROM), vol. 2, Issued on September 5, 2012, page: ROMBUNNO. 1L05

  However, first, in the method described in Non-Patent Document 1, a polymer is partially formed using a lattice photomask, and the obtained film has a narrow orientation region. It was. That is, the method disclosed in Non-Patent Document 1 is merely a method for producing a partially oriented film, and a technical method for producing an oriented film in which orientation is continuously formed in a large area. The above idea was not described in Non-Patent Document 1 at all. Moreover, in the manufacturing method actually used in the said nonpatent literature 1, the board | substrate (glass slide) which performed the rubbing process is used. Thus, the conventional method as disclosed in Non-Patent Document 1 is not a method that can efficiently produce a large-area oriented film.

  In addition, the conventional methods as described in Non-Patent Documents 1 and 2 above all use a combination of two or more monomers, and the mechanism for forming the orientation is the monomer at the time of photopolymerization. The use of molecular diffusion is explained. As described above, all of the conventional methods described in Non-Patent Documents 1 and 2 above use molecular diffusion of two or more monomers, and use two or more monomers as essential components. It is a method to do. On the other hand, none of the above Non-Patent Documents 1 and 2 describes or suggests that only one type of compound is used as a compound (monomer) exhibiting polymerizability.

  The present invention has been made in view of the above-described problems of the prior art. As a polymerizable compound, a polymerizable material containing only one kind of compound is used as a material for an oriented film, and a large area is aligned. It aims at providing the manufacturing method of the orientation film which makes it possible to manufacture the orientation film in which this was formed efficiently.

  As a result of intensive studies to achieve the above object, the inventors of the present invention are composed of a polymerizable material containing only one polymerizable compound exhibiting liquid crystallinity before and / or after polymerization as the polymerizable compound. Surprisingly, polymerization is initiated by using the membrane to move the boundary of the region continuously toward the unpolymerized region after starting the polymerization of the polymerizable material from a partial region of the membrane. Compound exhibiting liquid crystallinity existing in the film in the region (compound that is at least one of the polymerizable compound before polymerization and the compound obtained after polymerizing the polymerizable compound and exhibits liquid crystallinity) Even when a substrate or cell that has not been rubbed is used, the alignment region can be efficiently formed in a large area while moving the polymerization region. As a polymerizable compound, it is possible to efficiently produce an oriented film in which an oriented region is formed in a large area while using a polymerizable material containing only one kind of compound as the material of the oriented film. As a result, the present invention has been completed.

That is, the method for producing an oriented film of the present invention uses a film made of a polymerizable material containing only one type of polymerizable compound exhibiting liquid crystallinity before and / or after polymerization as a polymerizable compound.
After the polymerization of the polymerizable material is started from a partial region of the film, the boundary of the region is continuously directed toward the unpolymerized region at such a speed that the liquid crystalline compound existing in the film is oriented. It is the method characterized by obtaining an orientation film by moving it automatically.

  In the method for producing an oriented film of the present invention, the polymerizable material is polymerized by photopolymerization, and the boundary is continuously moved toward the unpolymerized region. It is preferable that the boundary is continuously moved toward an unirradiated region.

  Furthermore, in the method for producing an oriented film of the present invention, a boundary of the light irradiation region is obtained by using a photomask during the photopolymerization and continuously moving the photomask and / or the film. Is preferably moved continuously toward an unirradiated region of light. In addition, as such a photomask, a plurality of substantially rectangular openings are preferably formed such that the long sides of each opening are substantially parallel.

  In the method for producing an oriented film of the present invention, it is preferable to use a prepolymerized film as the film made of the polymerizable material.

Moreover, in the manufacturing method of the orientation film of the said invention, it is preferable that the speed | rate which moves the said boundary is 1 * 10 < ^-7 > -4 * 10 < ^-1 > m / s.

Furthermore, in the method for producing an oriented film of the present invention, the polymerizable compound is represented by the following general formula (1) and Z ¹ , Z ² , M ¹ , M ² , M ^{3 in the} formula: , L ¹ , L ² , p, q, and r are each preferably the following one compound selected from the group consisting of the following compounds C11 to C17.

Here, the compounds C11 to C17 that can be selected as the polymerizable compound are represented by the following general formula (1):
^{Z 1 p-M 1 -L 1} - (M 2 -L 2) q-M 3 -Z 2 r (1)
A compound represented by:
In compound C11, Z ¹ and Z ^{2 in} formula (1) may be the same or different, and each is a group represented by the formula: -L ³ -S ¹ -F ¹ , and F ¹ is an acrylic group Any one of a group and a methacryl group, S ¹ is any ^one of a single bond and a linear alkylene group having 1 to 12 carbon atoms, and L ³ is a single bond, an ether group, an ester group, and a carbonate group. Any one of these (more preferably an ether group), p is 1, M ¹ is a 1,4-phenylene group, and L ¹ is any ^one of a single bond and —COO— (more preferably). Is a single bond), q is 0, M ³ is a 1,4-phenylene group, and r is 1.
In the compound C12, Z ¹ and Z ² in the formula (1) may be the same or different, and each is a group represented by the formula: -L ³ -S ¹ -F ¹ , and F ¹ is acrylic Any one of a group and a methacryl group, S ¹ is either a single bond or a linear alkylene group having 1 to 12 carbon atoms, and L ³ is a single bond, an ether group, an ester group, or a carbonate group. 1 (more preferably an ether group), p is 1, M ¹ is a 1,4-phenylene group, L ¹ is —COO—, and M ² is 1,4-phenylene. A compound in which L ² is —OCO—, q is 1, M ³ is a 1,4-phenylene group, and r is 1;
In the compound C13, Z ¹ and Z ² in the formula (1) may be the same or different, and each is a group represented by the formula: -L ³ -S ¹ -F ¹ , and F ¹ is acrylic Or a methacryl group, and S ¹ is a group represented by the formula: (CH ₂ CH ₂ O) z (z is any one of 2 and 3), and L ³ Is a single bond, p is 1, M ¹ is a 1,4-phenylene group, L ¹ is either a single bond or an ester group (more preferably a single bond), and q is 0. , M ³ is a 1,4-phenylene group, and r is 1.
In compound C14, Z ¹ in formula (1) is a group represented by the formula: -L ³ -S ¹ -F ¹ , F ¹ is any one of an acryl group and a methacryl group, and S ¹ is A single bond, L ³ is a single bond, p is 1, M ¹ is a 1,4-phenylene group, L ¹ is a single bond, q is 0, M ³ is 1, 4-phenylene group, and Z ² is selected from a hydrogen atom, a halogen atom, a cyano group, a nitro group, an alkyl group having 1 to 12 carbon atoms, and an alkoxy group having 1 to 12 carbon atoms (more preferably Is a cyano group) and r is 1.
In compound C15, Z ¹ in formula (1) is a group represented by the formula: -L ³ -S ¹ -F ¹ , F ¹ is any one of an acryl group and a methacryl group, and S ¹ is A linear alkylene group having 1 to 12 carbon atoms, L ³ is an ether group, p is 1, M ¹ is a 1,4-phenylene group, L ¹ is a single bond, and q is 0 M ³ is a 1,4-phenylene group, Z ² is a hydrogen atom, a halogen atom, a cyano group, a nitro group, an alkyl group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms. A compound selected from one (more preferably a cyano group) and r is 1.
In compound C16, Z ¹ in formula (1) is a group represented by the formula: -L ³ -S ¹ -F ¹ , F ¹ is any one of an acryl group and a methacryl group, and S ¹ is A group represented by the formula: (CH ₂ CH ₂ O) z (z is 2 or 3), L ³ is a single bond, p is 1, M ¹ is a 1,4-phenylene group. L ¹ is a single bond, q is 0, M ³ is a 1,4-phenylene group, Z ² is a hydrogen atom, a halogen atom, a cyano group, a nitro group, or a carbon number of 1 to 12. A compound selected from an alkyl group and an alkoxy group having 1 to 12 carbon atoms (more preferably a cyano group), and r is 1.
In compound C17, Z ¹ is a group represented by the formula: -L ³ -S ¹ -F ¹ , F ¹ is any ^one of an acryl group and a methacryl group, and S ¹ has 1 to 12 carbon atoms A linear alkylene group, L ³ is an ether group, p is 1, M ¹ is a 1,4-phenylene group, L ¹ is —COO—, q is 0, and M ³ Is a 1,4-phenylene group, and Z ² is selected from a hydrogen atom, a halogen atom, a cyano group, a nitro group, an alkyl group having 1 to 12 carbon atoms and an alkoxy group having 1 to 12 carbon atoms (More preferably a cyano group) and r is 1.

  In addition, although the reason that the said objective is achieved by the manufacturing method of the orientation film of the said invention is not necessarily certain, the present inventors guess as follows. Here, in order to explain the reason why the above-described object is achieved, FIGS. 1 to 4 are taken by taking as an example a preferred embodiment of the present invention when a photopolymerizable compound is used as the polymerizable compound. While referring to, the compound which shows liquid crystallinity in the manufacturing method of the orientation film of this invention (The compound which is at least 1 sort (s) of the polymeric compound before superposition | polymerization, and the compound obtained after superposition | polymerization, and shows liquid crystallinity) The principle (the principle inferred by the present inventors) that makes it possible to orient the film will be described together. In the following description and drawings, the same or corresponding elements are denoted by the same reference numerals, and redundant description is omitted.

  FIG. 1 is a schematic longitudinal sectional view schematically showing a state before starting photopolymerization on a film made of a polymerizable material containing the polymerizable compound. 2 is a schematic longitudinal sectional view schematically showing a state in which polymerization is started from a partial region of the film by irradiating light from a light source, and FIG. 3 shows the boundary of the polymerization region in FIG. FIG. 4 is a schematic longitudinal sectional view schematically showing a state after being moved toward an unpolymerized region, and FIG. 4 is a state after the boundary of the polymerized region in FIG. 3 is moved toward the unpolymerized region. It is a schematic longitudinal cross-sectional view which shows typically. In the figure, the dotted line S indicates the boundary of the overlapping region, the arrow A conceptually indicates the direction in which the boundary S of the overlapping region is moved, and the arrow L conceptually indicates the light emitted from the light source. A1 conceptually shows a region polymerized by irradiation with light L (polymerization region: exposed portion), and A2 shows an unpolymerized region not irradiated with light L (unpolymerized region: light shielding portion). ) Conceptually, and A3 conceptually indicates a region where orientation is formed.

  In the embodiment shown in FIGS. 1 to 4, when producing an orientation film by photopolymerization, first, as shown in FIG. 1, the light emitted from the light source 11 and the light source 11 is transmitted. Two substrates 12 that can be used, a film 13 made of a polymerizable material disposed between the two substrates 12, and a photomask 14 that can block light emitted from the light source 11 are prepared. Then, the light source 11 is arranged on one of the two substrates 12, and the light from the light source 11 is irradiated only on a partial region of the film 13 between the film 13 and the light source 11. In addition, a photomask 14 capable of shielding a part of the film 13 is disposed. Next, as shown in FIG. 2, the light source 11 is turned on and the light L is emitted from the light source 11. When the light L is irradiated in this manner, the reaction does not proceed and remains unpolymerized in the light shielding portion A2, but the polymerization proceeds in the exposed portion A1 where the light is irradiated. In this way, a part of the region is exposed, and the polymerization of the polymerizable material is started from a part of the film 13 (exposed portion) A1. And in the area | region (polymerization area | region: exposure part) A1 superposed | polymerized in this way, the said polymeric compound (monomer) in the said polymeric material is superposed | polymerized, and a polymer (polymer) is formed. Therefore, in the polymerization region (exposed portion) A1, polymerization proceeds and the monomer concentration decreases. Thereby, the concentration of the monomer existing in the film is biased between the polymerization region (exposed portion) A1 and the unpolymerized region (light-shielding portion) A2. In general, when an uneven concentration of a compound occurs in a film, the substance diffuses in a direction to eliminate the concentration gradient due to the substance diffusion phenomenon. Therefore, when light is irradiated as described above, the polymerized region (exposed portion) A1 and the unpolymerized region (light-shielding) are used even if a polymerizable material containing only one kind of compound as the polymerizable compound is used as the film material. Part) At the boundary S of A2, the monomer concentration is biased, and this induces the diffusion of the compound (monomer and / or polymer) in the direction of eliminating the concentration gradient. Then, a monomer flow mainly occurs from the light-shielding portion A2 that is an unpolymerized region to the exposed portion A1 that is a polymerized region, and a polymer is mainly generated from the polymerized region (exposed portion) A1 to the unpolymerized region (light-shielding portion) A2. It is inferred that this flow will occur. As the flow of such a compound, the flow of a compound having a smaller molecular weight and being easy to move tends to be larger. When a flow of the compound is generated between the unpolymerized region A2 and the polymerization region A1 in this manner, the flow causes a compound exhibiting liquid crystallinity existing in the polymerization region in the film (polymerization before polymerization existing in the polymerization region). The compound (monomer) and the compound (polymer) obtained after the polymerization, which is a compound exhibiting liquid crystallinity) are subjected to a kind of shear stress, and the compound exhibiting the liquid crystallinity is a polymerization region. Orientation is performed in a region in the vicinity of the boundary S between the (exposed portion) A1 and the unpolymerized region (light-shielding portion) A2, and an alignment region A3 is formed (induced). Note that the direction in which the flow due to the movement of such a compound occurs is substantially perpendicular to the boundary S between the polymerization region (exposure portion) A1 and the non-polymerization region (light-shielding portion) A2. In the case of a rod-like one, the average orientation direction is usually a direction substantially perpendicular to the boundary S. Here, as in the above-described prior art (Non-patent Document 1), a case where the position of the boundary S is fixed by fixing the photomask 14 at the position shown in FIG. As the internal viscosity increases, the diffusion of the compound is suppressed, the orientation region is limited to the region near the boundary, and approximately several tens to several hundreds μm in the direction perpendicular to the boundary of the light irradiation region. Only an alignment region is formed in a certain region. On the other hand, in the preferred embodiment of the present invention shown in FIGS. 1 to 4, as shown in FIGS. Is moved toward the unpolymerized region A2 (in this embodiment, the boundary S is moved toward the unpolymerized region A2 by continuously moving the photomask 14). Then, after the polymerization of the polymerizable material is started from a partial region of the film 13 (see FIG. 2), the boundary S of the polymerization region is continuously moved toward the unpolymerized region A2 (FIG. 2). -4), at the point where the boundary S moves (at a new position), the diffusion of the compound existing in the film is induced, which continuously causes photopolymerization and orientation induced by diffusion. It becomes possible. At this time, the compound exhibiting liquid crystallinity is formed at a speed at which the compound exhibiting liquid crystallinity is aligned (a kind of shear stress generated by the movement of the above-described compound (monomer and / or polymer) causes the compound exhibiting liquid crystallinity to form alignment). By continuously moving the boundary S (at such a rate that it can be applied sufficiently), it is possible to produce a diffusion-induced orientation continuously. Therefore, in the present invention, the alignment region is continuously increased by continuously moving the boundary S of the polymerization region A1 toward the unpolymerized region at a speed at which the compound exhibiting liquid crystallinity is aligned. It is possible to make it. Further, when the compound exhibiting liquid crystallinity is aligned by the shear stress, once the alignment starts, the alignment is amplified by the self-organizing ability of the liquid crystal, so that the alignment is formed more efficiently. The Rukoto. As described above, in the conventional techniques as described in Non-Patent Documents 1 and 2 above, it has been essential to use two or more monomers as the polymerizable compound. The present inventors infer that the alignment region can be continuously increased as described above, even though only one compound is used as the compound. Therefore, in the present invention, a large area is used as the polymerizable compound, although a film made of a polymerizable material containing only one type of polymerizable compound exhibiting liquid crystallinity before and / or after polymerization is used. The present inventors speculate that it is possible to efficiently produce an orientation film in which an orientation region is formed. In addition, as described above, the present invention moves the boundary S between the overlap region (exposure portion) A1 and the unpolymerization region (light-shielding portion) A2 toward the unpolymerization region A2, thereby moving the boundary S that moves. Since this is a method that allows the diffusion region to be continuously increased by sequentially causing a substance diffusion phenomenon in a nearby region, a substrate that has not been subjected to a pretreatment for providing an alignment regulating force (for example, Even in the case of using a substrate that is not subjected to rubbing treatment, etc., an orientation film can be produced efficiently. Therefore, it is possible to efficiently avoid problems such as dust generation and static electricity caused by the rubbing process, and dust adhesion and mixing on the orientation film, and in addition, the substrate and the cell are previously provided with orientation regulation power. Therefore, it can be said that it is an efficient method in terms of workability. In the examples shown in FIGS. 1 to 4, the principle of forming the alignment is described by taking the case where a photopolymerizable compound is used as the polymerizable compound as an example. (Exposure part) By utilizing the diffusion phenomenon of the substance generated by moving the boundary S between A1 and the unpolymerized area (light-shielding part) A2 toward the unpolymerized area A2, the orientation area is formed by forming an orientation in the film. The polymerizable compound is not limited to a photopolymerizable compound, and is a compound other than a photopolymerizable compound (for example, a thermopolymerizable compound) because it is a method that enables increase. May be used.

  Further, in the method for producing an oriented film of the present invention, the compound exhibiting liquid crystallinity is oriented using a compound that moves from an unpolymerized region to a polymerized region in the film after the polymerization is started. It is possible to control the direction of orientation in the direction in which the compound moves (direction approximately perpendicular to the boundary of the region). Therefore, for example, when polymerization is performed by photopolymerization, the orientation can be controlled in various directions according to the shape of the mask.

  Here, the control of the orientation direction will be briefly described with reference to another embodiment suitable for the present invention shown in FIG. FIG. 5A shows the relationship before starting photopolymerization between the photomask 14 and the substrate 12 (before moving the boundary S of the light irradiation region) when viewed from the light source side (the optical axis direction of the light to be irradiated). 5 (b) is a schematic plan view schematically showing the relationship between the photomask 14 and the substrate 12 after photopolymerization when viewed from the light source side (the boundary S of the light irradiation region). It is the schematic plan view which shows typically the state moved to the direction of arrow A). In FIG. 5, the boundary S of the overlapping region A1 is perpendicular to the two sides of the substrate 12, and when the boundary S is moved as schematically shown in FIGS. Is a flow of the compound substantially perpendicular to the boundary S, and the orientation direction is controlled substantially perpendicular to the boundary S (the arrow P in the figure conceptually indicates the direction perpendicular to the boundary S). It is assumed that the flow of the compound occurs in substantially the same direction as the arrow P and / or in the direction 180 ° opposite to that). On the other hand, when the edge of the mask 14 is inclined and the boundary S is moved so that the boundary S is in contact with the two sides of the substrate 12 at an angle other than perpendicular, the mask S 14 is moved with respect to the oblique boundary S. When the moving speed of the boundary S is almost vertical or the moving speed of the boundary S is high, the orientation direction is controlled in the direction of the vector sum of the vector of the moving direction of the boundary S and the vector perpendicular to the boundary S. The control of the alignment direction when the edge of the mask 14 is inclined in this way will be described in more detail with reference to another embodiment suitable for the present invention shown in FIG. FIG. 6 is a schematic plan view schematically showing the relationship between the photomask 14 and the substrate 12 when viewed from the light source side (the optical axis direction of light to be irradiated). The photomask 14 shown in FIG. 6 is formed so that the edges are formed obliquely and the boundary S is in contact with the two sides of the substrate 12 at an angle other than perpendicular. Then, when photopolymerization is performed while continuously moving such a boundary S in the direction of arrow A in the drawing (for example, photopolymerization is performed while continuously moving the mask 14 in the direction of arrow A). Basically, the compound flows in a direction substantially perpendicular to the boundary S of the mask due to the diffusion induction of the compound (monomer and / or polymer) in the film (the arrow P in the figure indicates the boundary). The direction perpendicular to S is shown for conceptual description, and the compound flow is presumed to occur in substantially the same direction as the arrow P and / or in the direction opposite to 180 ° thereof). Therefore, when photopolymerization is performed while continuously moving such a boundary S in the direction of the arrow A in the figure, the direction substantially perpendicular to the oblique boundary S (the same direction as the arrow P) ), The orientation direction is controlled. As described above, when the moving speed of the boundary S is high, the vector of the moving direction of the boundary S (the direction indicated by the arrow A) and the vector perpendicular to the boundary S (the direction indicated by the arrow P) The orientation direction is controlled in the direction of the vector sum.

  Therefore, the boundary S is moved when the boundary S is moved as schematically shown in FIGS. 5A and 5B, and the edge of the mask 14 is inclined as schematically shown in FIG. In some cases, the orientation direction is controlled in different directions. Thus, in the case of employing photopolymerization, it is possible to obtain films having different orientation directions depending on the shape of the edge of the mask 14.

  As described above, the present invention is a method that allows the orientation region to be increased by utilizing the diffusion phenomenon of the substance while moving the boundary of the polymerization region, thereby increasing the orientation region. The present inventors speculate that it is possible to efficiently produce an orientation film having a property and having an orientation region formed in a large area.

  According to the present invention, while using a polymerizable material containing only one compound as the polymerizable compound as the material for the oriented film, an oriented film having an oriented region formed on a large area can be efficiently produced. It becomes possible to provide the manufacturing method of the orientation film which enables this.

It is a schematic longitudinal cross-sectional view which shows typically the state before starting photopolymerization with respect to the film | membrane which consists of polymeric materials. It is a schematic longitudinal cross-sectional view which shows typically the state which irradiated the light from the light source and started superposition | polymerization from the one part area | region of the film | membrane. It is a schematic longitudinal cross-sectional view which shows typically the state after moving the boundary of the superposition | polymerization area | region in FIG. 2 toward the unpolymerization area | region. It is a schematic longitudinal cross-sectional view which shows typically the state after moving the boundary of the superposition | polymerization area | region in FIG. 3 toward the unpolymerization area | region. FIG. 5 (a) is a schematic plan view schematically showing a relationship before starting photopolymerization between the photomask and the substrate when viewed from the light source side (state before moving the boundary of the light irradiation region), FIG. 5B is a schematic plan view schematically showing a relationship after starting photopolymerization between the photomask and the substrate (a state where the boundary of the light irradiation region is moved) when viewed from the light source side. It is a schematic plan view which shows typically the relationship before the photoinitiation of the photomask and substrate which formed the edge diagonally when it sees from the light source side. It is a schematic plan view which shows typically the relationship before the photopolymerization start of the photomask which has a some rectangular opening part, and a board | substrate when it sees from the light source side. It is a schematic plan view which shows typically the relationship before the photopolymerization start of the photomask which has a some rectangular opening part, and a board | substrate when it sees from the light source side.

  Hereinafter, the present invention will be described in detail with reference to preferred embodiments thereof.

The method for producing an oriented film of the present invention uses, as a polymerizable compound, a film made of a polymerizable material containing only one type of polymerizable compound exhibiting liquid crystallinity before and / or after polymerization.
After the polymerization of the polymerizable material is started from a partial region of the film, the boundary of the region is continuously directed toward the unpolymerized region at such a speed that the liquid crystalline compound existing in the film is oriented. It is the method characterized by obtaining an orientation film by moving it automatically.

  Such a polymerizable material contains only one polymerizable compound exhibiting liquid crystallinity before and / or after polymerization as a polymerizable compound. As described above, in the present invention, an oriented film in which a sufficiently uniform orientation is formed in a large area while utilizing a film made of a polymerizable material using only one kind of compound as the polymerizable compound. Makes it possible to obtain

  As such a polymerizable compound, those having one or more (more preferably 1 to 6) polymerizable functional groups are preferable. If the number of such polymerizable functional groups is less than the lower limit, polymerization does not occur, and thus an orientation film can be formed by orientation utilizing diffusion of a compound resulting from a change in the concentration of the polymerizable compound (monomer). It becomes difficult. Further, if the number of such polymerizable functional groups exceeds the upper limit, the polymerization proceeds faster than the diffusion of the compound, so that it tends to be difficult to form an orientation associated with the diffusion.

  In addition, such a polymerizable functional group is not particularly limited, and a known functional group can be appropriately used. For example, a vinyl group, an allyl group, a vinyl ether group, an acrylic group, a methacryl group, an oxetane group, an epoxy group. , Cinnamoyl group, chalcone group, coumarin group and the like. Among them, vinyl ether group, acryl group, methacryl group, oxetane group, epoxy group, cinnamoyl group, chalcone group from the viewpoint of ease of synthesis of compound, handling property, etc. Are preferable, and an acrylic group, a methacryl group, an oxetane group, and an epoxy group are more preferable.

  Furthermore, in the present invention, from the viewpoint of amplifying the alignment by the self-organization ability of the liquid crystal, the polymerizable compound needs to be a compound exhibiting liquid crystallinity before and / or after polymerization (at least after polymerization). The component derived from the polymerizable compound present in the film (the polymerizable compound itself, a polymer of the polymerizable compound) needs to exhibit liquid crystallinity). As used herein, “a compound exhibiting liquid crystallinity after polymerization” means that a compound obtained by polymerizing the polymerizable compound exhibits liquid crystallinity (a homopolymer of a polymerizable compound ( Polymer) is a compound exhibiting liquid crystallinity). Further, the “compound exhibiting liquid crystallinity” mentioned here is preferably a compound exhibiting liquid crystallinity in a predetermined temperature range (so-called thermotropic liquid crystal compound). Note that such a thermotropic liquid crystal compound is an enantiotropic liquid crystal compound that exhibits liquid crystallinity in both the temperature rising process and the temperature lowering process when the behavior of the liquid crystal phase is confirmed when the temperature is raised and lowered. Alternatively, it may be a monotropic liquid crystal compound exhibiting liquid crystallinity only in one of the temperature raising process and the temperature lowering process. In the present invention, at least one of the polymerizable compound (monomer) before polymerization and the compound (polymer: polymer) obtained by polymerizing the polymerizable compound is a compound exhibiting liquid crystallinity (liquid crystal If the diffusion of the compound (monomer and / or polymer) in the film is excited by the start of polymerization, a shear stress is applied to the compound exhibiting liquid crystallinity. Thus, once the alignment of the compound having liquid crystallinity is started, the alignment is amplified by the self-organizing ability of the liquid crystal, so that the alignment can be formed efficiently.

Moreover, as said polymeric compound, following General formula (1):
^{Z 1 p-M 1 -L 1} - (M 2 -L 2) q-M 3 -Z 2 r (1)
[Wherein, Z ¹ and Z ² are each independently a hydrogen atom; a halogen atom (more preferably F, Cl, Br); CN; NO ₂ ; OCF ₃ ; a linear or branched group having 1 to 18 carbon atoms. Alkyl group {in addition, the alkyl group is an oxygen atom, —COO—, —OCO—, —OCOO—, —CONR ¹ —, in which one or a plurality of carbons are not continuously bonded. , —NR ¹ CO—, —OCO—NR ¹ —, or —NR ¹ COO— may be substituted (wherein R ¹ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms). . }; Alkoxy group having 1 to 18 carbon atoms; and the ^formula: -L 3 ^-S 1 -F ¹
{In the formula: F ¹ represents the following formulas (F-1) to (F-20):

(Wherein R ² represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms),
Any one of the groups represented by
S ¹ is a single bond, a linear or branched alkylene group having 1 to 18 carbon atoms (in the alkylene group, one or a plurality of carbons in the alkylene group are not continuously bonded). oxygen atom, -COO -, - OCO -, - OCOO -, - CONR 3 -, - NR 3 CO -, - OCO-NR 3 -, or ^-NR 3 may be substituted with COO- (wherein, R ³ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms)).
L ³ represents a single _{bond, -O -, - S -,} - OCH 2 -, - CH 2 O -, - CO -, - CH 2 -CH 2 -, - CF 2 -CF 2 -, - COO-, ^{-OCO -, - OCOO -, -} CONR 4 -, - NR 4 CO -, - OCO-NR 4 -, - NR 4 COO -, - CH = CH -, - CF = CF -, - CH = CH-COO -, -OCO-CH = CH-, or -C≡C- (wherein, R ⁴ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms). }
Any one of the groups represented by
L ^{1, L 2} are each independently a single _{bond, -O -, - S -,} - OCH 2 -, - CH 2 O -, - CO -, - CH 2 -CH 2 -, - CF 2 -CF _{^{2 -, - COO -, -}} OCO -, - CONR 4 -, - NR 4 CO -, - OCO-NR 4 -, - NR 4 COO -, - CH = CH -, - CF = CF -, - CH = CH—COO—, —OCO—CH═CH—, or —C≡C— (wherein R ⁴ represents a hydrogen atom or an alkyl group having 1 to 6 carbon atoms),
M ¹ and M ³ are each independently 1,4-phenylene group, 1,4-cyclohexylene group, pyridine-2,5-diyl group, pyrimidine-2,5-diyl group, naphthalene-2,6. -Diyl group, naphthalene-1,4-diyl group, 1,3-dioxane-2,6-diyl group, 1,3,4-benzenetoluyl group, 1,3,5-benzenetoluyl group, 1,3,3 4,5-benzenetetrayl group, M ² is 1,4-phenylene group, 1,4-cyclohexylene group, pyridine-2,5-diyl group, pyrimidine-2,5-diyl group, naphthalene- Represents a 2,6-diyl group, a naphthalene-1,4-diyl group or a 1,3-dioxane-2,6-diyl group;
The hydrogen atoms contained in the groups selected as M ¹ , M ² and M ³ may each independently be substituted with an alkyl group, a halogenated alkyl group, an alkoxy group, a halogen group, a cyano group or a nitro group. ,
p and r each independently represent 1, 2, or 3;
q represents 0, 1, or 2;
When there are a plurality of Z ¹ and / or Z ² , they may be the same or different. ]
The compound represented by these is preferable.

  The polymerizable compound is not particularly limited as long as it exhibits liquid crystallinity before and / or after polymerization, and therefore, other than the compound represented by the general formula (1), Alternatively, any material that exhibits liquid crystallinity after polymerization can be suitably used. Examples of compounds that can be used other than the compound represented by the general formula (1) include a structure other than the structure represented by the general formula (1), and a vinyl group, an allyl group, a vinyl ether group, A compound having a functional group such as an acryl group, a methacryl group, an oxetane group, an epoxy group, a cinnamoyl group, a chalcone group, or a coumarin group can be appropriately used. Many of the components that can be used as such a polymerizable compound (for example, various thermal polymerization compounds and photopolymerization compounds exhibiting liquid crystallinity before and / or after polymerization) are commercially available, and these are used appropriately. May be.

  Moreover, as the polymerizable compound to be contained in the polymerizable material, it is easy to control the position of the boundary between the polymerized region and the unpolymerized region at the time of polymerization, and it is possible to form a film having a desired orientation more efficiently. Since it becomes possible and working efficiency can be further improved, it is preferable to use a photopolymerizable compound. That is, in the present invention, it is preferable that the polymerizable compound is a photopolymerizable compound and the polymerizable material is polymerized by photopolymerization. In addition, the photopolymerizable compound mentioned here is a compound in which a functional group reacts due to the presence of a photoinitiator such as vinyl group, allyl group, vinyl ether group, acrylic group, methacryl group, oxetane group, and epoxy group. Alternatively, a compound in which a functional group reacts with light without a photoinitiator may be used. Examples of photopolymerizable compounds that react with functional groups without a photoinitiator include compounds having functional groups capable of photodimerization such as cinnamoyl groups, chalcone groups, and coumarin groups. it can.

Moreover, as said polymeric compound, from a viewpoint that it is a monomer which can advance superposition | polymerization more efficiently, and a viewpoint that it becomes possible to form an orientation film more efficiently, the said General formula (1) In which Z ¹ and Z ² are both groups represented by -L ³ -S ¹ -F ¹ (wherein Z ¹ and Z ² may be the same) They may be different and are preferably the same group from the viewpoint of ease of synthesis.), F ¹ is an acryl group or a methacryl group, and S ¹ is a single bond or a straight chain having 1 to 12 carbon atoms. A chain alkylene group, and L ³ is a single bond, an ether group (—O—), an ester group (—COO—, —OCO—) or a carbonate group (—OCOO—) (more preferably an ether group). ) And There is 1, a ^{M 1} is 1,4-phenylene group, a one of ^{L 1} is a single bond and -COO- (more preferably a single bond), q is 0, the ^{M 3} A compound C11 which is a 1,4-phenylene group and r is 1;
The compound represented by the general formula (1), wherein Z ¹ and Z ² are both groups represented by -L ³ -S ¹ -F ¹ (wherein Z ¹ and Z ² are They may be the same or different, and are preferably the same group from the viewpoint of ease of synthesis.), F ¹ is an acrylic group or a methacryl group, and S ¹ is a single bond or a carbon number. 1 to 12 linear alkylene groups, L ³ is any one of a single bond, an ether group, an ester group and a carbonate group (more preferably an ether group), p is 1, and M ¹ is 1 , 4-phenylene group, L ¹ is —COO—, M ² is 1,4-phenylene group, L ² is —OCO—, q is 1, M ³ is 1,4 A compound C12 which is a -phenylene group and r is 1;
The compound represented by the general formula (1), wherein both Z ¹ and Z ² are groups represented by -L ³ -S ¹ -F ¹ (wherein Z ¹ and Z ² are They may be the same or different, and are preferably the same group from the viewpoint of ease of synthesis.), F ¹ is an acrylic group or a methacryl group, and S ¹ is represented by the formula: (CH ₂ CH ₂ O) z (z is 2 or 3), L ³ is a single bond, p is 1, M ¹ is a 1,4-phenylene group, and L ¹ Is a single bond or an ester group (more preferably a single bond), q is 0, M ³ is a 1,4-phenylene group, and r is 1, Compound C13,
A compound represented by the general formula (1), wherein Z ¹ is represented by -L ³ -S ¹ -F ¹ , F ¹ is an acrylic group or a methacryl group, and S ¹ is a single group. A bond, L ³ is a single bond, p is 1, M ¹ is a 1,4-phenylene group, L ¹ is a single bond, q is 0, and M ³ is 1,4. A phenylene group, and Z ² is selected from a hydrogen atom, a halogen atom, a cyano group, a nitro group, an alkyl group having 1 to 12 carbon atoms and an alkoxy group having 1 to 12 carbon atoms (more preferably A cyano group) and r is 1, a compound C14,
A compound represented by the general formula (1), wherein Z ¹ is represented by -L ³ -S ¹ -F ¹ , F ¹ is an acryl group or a methacryl group, and S ¹ is carbon. A linear alkylene group of 1 to 12, L ³ is an ether group, p is 1, M ¹ is a 1,4-phenylene group, L ¹ is a single bond, and q is 0 Yes, M ³ is a 1,4-phenylene group, and Z ² is selected from a hydrogen atom, a halogen atom, a cyano group, a nitro group, an alkyl group having 1 to 12 carbon atoms, and an alkoxy group having 1 to 12 carbon atoms A compound C15 in which r is 1 (more preferably a cyano group) and r is 1;
A compound represented by the general formula (1), wherein Z ¹ is represented by -L ³ -S ¹ -F ¹ , F ¹ is an acrylic group or a methacryl group, and S ¹ is represented by the formula : (CH ₂ CH ₂ O) z (z is 2 or 3), L ³ is a single bond, p is 1, M ¹ is a 1,4-phenylene group. Yes, L ¹ is a single bond, q is 0, M ³ is a 1,4-phenylene group, Z ² is a hydrogen atom, a halogen atom, a cyano group, a nitro group, or an alkyl having 1 to 12 carbon atoms. A compound C16 selected from the group consisting of a group and an alkoxy group having 1 to 12 carbon atoms (more preferably a cyano group), and r is 1, and
A compound represented by the general formula (1), wherein Z ¹ is represented by -L ³ -S ¹ -F ¹ , F ¹ is an acryl group or a methacryl group, and S ¹ is carbon. A linear alkylene group of 1 to 12, L ³ is an ether group, p is 1, M ¹ is a 1,4-phenylene group, L ¹ is —COO—, and q is 0 M ³ is a 1,4-phenylene group, Z ² is a hydrogen atom, a halogen atom, a cyano group, a nitro group, an alkyl group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms. Compound C17, which is one selected (more preferably a cyano group) and r is 1.
Is more preferable.

  Examples of such compounds C11-17 include 4,4′-bis (8- (meth) acryloyloxy-3,6-dioxaoctyl-1-oxy) biphenyl, 4,4′-bis (9- (Meth) acryloyloxy) nonyloxybiphenyl, 4,4′-bis (6- (meth) acryloyloxy) hexyloxybiphenyl, 1,4-bis (6- (meth) acryloyloxyhexyloxy) methylhydroquinone, 4- (6- (meth) acryloyloxyhexyloxy) -4′-cyanobiphenyl, 4- (9- (meth) acryloyloxynonyloxy) -4′-cyanobiphenyl, 4- (5- (meth) acryloyloxy-3 -Oxapentyl-1-oxy) -4'-cyanobiphenyl, 4- (8- (meth) acryloyloxy-3,6-dioxao Chill-1-oxy) -4'-cyanobiphenyl, 4-cyanophenyl-4- (2-acryloyloxy ethoxy) benzoate are mentioned as preferred.

  Further, such a polymerizable material contains only one type of compound as the polymerizable compound (only one type of polymerizable compound exhibiting liquid crystallinity before and / or after polymerization). . In such a polymerizable material, in addition to the polymerizable compound, other components other than the compound exhibiting the polymerizable property (compound not exhibiting the polymerizable property) may be appropriately contained within a range not impairing the effects of the present invention. Other components (compounds that do not exhibit polymerizability) that can be contained in such a polymerizable material include various solvents, photopolymerization initiators, viscosity modifiers, plasticizers, polymerization inhibitors, surfactants, and the like. Can be mentioned. In addition, when other components (such as various additives) are contained in the polymerizable material as described above, the content of the polymerizable material in the polymerizable material is 70 mol% or more (more preferably). 80 mol% or more). When the content of the polymerizable material is less than the lower limit, the amount of the compound exhibiting liquid crystallinity in the polymerized film tends to be lowered, and it tends to be difficult to form an alignment.

  In addition, when the polymerizable compound in the polymerizable material is photopolymerized, it is preferable to use a photopolymerization initiator together with the polymerizable compound because the polymerization can proceed more efficiently. Such a photopolymerization initiator is not particularly limited, and known ones can be used as appropriate, and commercially available products (for example, trade name “Irgacure 651” manufactured by BASF) may be used. Further, in the case of using such a photopolymerization initiator, the amount used can be appropriately designed according to the type of polymerizable compound in the polymerizable material to be used, the light absorption wavelength, etc. It is good also as 0.1-10 mol% with respect to all the compounds in an electroconductive material. In addition, when the content ratio of such a photopolymerization initiator is less than the lower limit, the effect of using the photopolymerization initiator tends to be insufficient, and on the other hand, when the upper limit is exceeded, liquid crystallinity tends to be reduced, As a result, good orientation tends not to be obtained efficiently.

  Moreover, the form (size including thickness etc.) of such a polymerizable material is not particularly limited, and the form can be appropriately changed according to the target design. It is good also as 1-200 micrometers. In addition, the film made of such a polymerizable material may be a coating film obtained by applying the polymerizable material on a substrate, and the polymerizable material is introduced into a so-called cell and polymerized by the cell. The material may be in the form of a film, and the formation method of the film and the presence or absence of the use of the substrate during the production are not particularly limited, and known methods can be used as appropriate, and the conditions are polymerizable. It can be appropriately selected according to the kind of the polymerizable compound in the material, the polymerization method (photopolymerization or thermal polymerization), the use of the final product, and the like. Furthermore, when manufacturing the film | membrane which consists of said polymeric material on a board | substrate or in a cell, the board | substrate etc. to be used may not be horizontal.

  In addition, as a film made of such a polymerizable material, a film of the polymerizable material is disposed between the two substrates from the viewpoint of forming an orientation film while sufficiently maintaining the shape and uniformity of the film. The film is supported by the substrate (for example, a film is disposed in the cell using a cell including two substrates), or the film made of the polymerizable material is formed on one substrate, The other surface is preferably a gas phase interface. Moreover, the material of such a substrate or cell is not particularly limited, and a known material (for example, glass or plastic) can be appropriately used. Further, in the case where the polymerization is performed by photopolymerization, in the case where the substrate is in contact with the light incident surface side of the film, it is necessary to make light incident through the substrate. It is preferable to be made of a material that can transmit at least light having a wavelength used for photopolymerization.

  Furthermore, in the present invention, polymerization of the polymerizable material is started from a partial region of the film using a film made of such a polymerizable material. In addition, in the “starting the polymerization of the polymerizable material from a partial region of the film” mentioned here, for example, a part of the film is set as a region for starting the polymerization from the beginning, and the polymerization is started from the region. In the case of starting (for example, in the case of photopolymerization, a part of the film is previously present in a part (exposed part) irradiated with light from the light source, and the polymerizable material is exposed from the exposed part of the film. In the case of starting polymerization from a partial region of the film while gradually forming a region for polymerization (for example, in the case of photopolymerization using a photomask), After covering the entire film and putting it in a state where all the film enters the part shielded from light by the mask, the film is gradually exposed to the light irradiation region during light irradiation, and the film is exposed. Polymerization starts from the part of the film (part of the film) If such: It should be noted that including this case, introducing the film at a rate such that the compound in the irradiated region of the light indicating the liquid crystal is oriented (exposure) is to be preferred)..

  Thus, the method for polymerizing the film made of the polymerizable material from a partial region is not particularly limited, and a known method can be appropriately employed. As a method for starting polymerization from a partial region of such a film, for example, light (X-ray, electron beam, ultraviolet ray, visible light, infrared ray (heat ray), etc.) is irradiated on a partial region, Examples thereof include a photopolymerization method in which polymerization is started from an irradiation region, and a thermal polymerization method in which heating is started from a partial region and polymerization is started from the heating region. As such a polymerization method, in part from the viewpoint of easier control of the region to be polymerized, ease of handling, ease of setting and management of irradiation intensity and irradiation energy of light to be irradiated. It is preferable to employ a photopolymerization method in which light is irradiated to the region. In such photopolymerization, when the film that is the object of photopolymerization is supported by a cell or the like, if the substrate on the light irradiation surface side is not transparent, photopolymerization is performed by using an electron beam. And the use of electron beams is useful when the substrate is not transparent.

  Furthermore, when photopolymerization is employed as the polymerization method of the polymerizable material, it is preferable to use ultraviolet rays or visible light because the polymerization reaction can proceed more efficiently. The light source for irradiating such light is not particularly limited, and a known light source that can be used for photopolymerization can be appropriately used. For example, a high-pressure mercury lamp, an ultra-high pressure mercury lamp, a low-pressure mercury lamp, a metal halide lamp, an LED A lamp or the like may be used.

  Moreover, there is no limitation in particular as the irradiation wavelength of the light utilized in such photopolymerization, What is necessary is just to consider and consider the absorption spectrum of a compound, the recommended use wavelength of a photoinitiator, etc. In addition, for example, when polymerization is performed in a state where a film made of a polymerizable material is formed on a substrate and one interface of the film is in contact with the surrounding atmospheric gas, a compound containing an acrylic group or a methacryl group is used. When a radical reaction is used, it is preferable to carry out the polymerization in an inert gas atmosphere such as nitrogen from the viewpoint that, when oxygen is present, it is difficult for the polymerization to proceed due to oxygen inhibition. In the case of a polymerizable functional group having no influence of oxygen inhibition using a cation reaction such as an oxetane group or an epoxy group, it is not necessary to perform polymerization in an inert atmosphere, and the polymerization may be performed in the air. On the other hand, when a film made of a polymerizable material using a cell or the like is not in contact with the atmospheric gas, the polymerization may be started in the air. Thus, in the present invention, the polymerization may be performed in a state where the film made of the polymerizable material is in contact with the atmospheric gas (the state where the interface of the film is in contact with the gas phase), and the film made of the polymerizable material is in the atmosphere. The polymerization may be performed in a state where it does not come into contact with the gas (a state where the interface of the film is in contact with the wall surface (solid phase) of the cell).

  In addition, when photopolymerization is employed as a polymerization method for the polymerizable material, light irradiation may be performed under heating conditions, and the heating temperature is determined depending on the type of polymerizable material used, the type of polymerization reaction, the liquid crystallinity, Although it can select suitably considering the viscosity of a polymeric material, the ease of a heating, etc., Usually, it is preferable to set it as room temperature (about 25 degreeC)-about 300 degreeC. If the heating temperature is less than the lower limit, it may be difficult to efficiently advance the polymerization reaction or the formation of the alignment film due to crystallization of the polymerizable material or one of the components, or the viscosity of the polymerizable material. However, when the upper limit is exceeded, polymerization of the entire film proceeds by heat before irradiating the polymerizable compound with light. Therefore, the orientation film cannot be obtained, or when the reaction is performed in the air, the possibility that the polymerizable compound is decomposed increases and it becomes difficult to stably obtain the orientation film.

At the time of the photopolymerization, it is preferable to irradiate light at an intensity of ^{0.1μW / cm 2 ~30mW / cm 2} , the light intensity of 0.5μW ^/ cm ² ~10mW ^/ cm 2 Irradiation is more preferable. If the illuminance of such light is less than the lower limit, the reaction rate is slow, so the transition speed of the boundary is slow, and the productivity tends to decrease. On the other hand, when the upper limit is exceeded, the polymerizable compound diffuses. When the polymerization reaction rate is too high, the compound is not sufficiently diffused, and the orientation film tends to be not obtained.

  Furthermore, the method for irradiating light from a part of the region during such photopolymerization is not particularly limited. For example, a light source that can irradiate only part of the region can be used. Alternatively, light may be irradiated from a part of the region using a photomask, but it is preferable to use a photomask because the control of the polymerized region and the unpolymerized region becomes easier.

  In the present invention, as described above, after the polymerization of the polymerizable material is started from a partial region of the film made of the polymerizable material, the compound exhibiting liquid crystallinity existing in the film (polymerization) The previous polymerizable compound (monomer) and / or the compound (polymer) obtained after polymerization of the polymerizable compound, which is a compound exhibiting liquid crystallinity) is unpolymerized at the boundary of the region at such a rate that the liquid crystallinity is aligned. Move continuously towards the area. In this way, by continuously moving the boundary between the polymerized region and the unpolymerized region toward the unpolymerized region, the polymerization is continuously performed, and the region in the vicinity of the moving boundary is in the film. The diffusion phenomenon of the compound (the monomer and / or polymer) substance can be successively and continuously caused, whereby the orientation region can be continuously increased to obtain an orientation film. As the polymerization conditions for continuously moving the boundary of the region toward the unpolymerized region in this way, the same conditions as the polymerization conditions at the start of the polymerization described above may be employed.

  Here, “the speed at which the compound exhibiting liquid crystallinity is oriented”, which is the moving speed when moving the boundary, is formed by polymerization, the type of compound exhibiting liquid crystallinity, the type of compound that diffuses and moves, and polymerization. The liquid crystallinity in the film is also exhibited depending on the type of compound (polymerized product: polymer), the type of polymerizable compound, the polymerization conditions employed during polymerization (eg, light irradiation conditions when photopolymerization is employed, etc.), etc. Since the time required to orient the compound is different, it cannot be generally stated. That is, in the present invention, due to the concentration gradient of the compound generated in the polymerized region and the unpolymerized region, the compound (mainly monomer and / or Or a polymer), causing a diffusion movement (flow) of the polymer, and applying a kind of shear stress to the compound exhibiting liquid crystallinity existing in the polymerizable material to align the compound exhibiting liquid crystallinity in the vicinity of the boundary. Therefore, the “speed at which a compound exhibiting liquid crystallinity is aligned” varies depending on the type of compound exhibiting liquid crystallinity, the type of compound that diffuses and moves, and the like. For example, when the polymerization rate of the polymerizable compound is very high, a concentration gradient of the compound (monomer and / or polymer) in the film suddenly occurs in the polymerized region and the unpolymerized region, leading to the polymerized region of the polymerizable compound. The moving speed of is very fast. In such a case, even if the moving speed of the boundary is relatively high, the shear stress generated by the movement of the polymerizable compound to the polymerization region is sufficient for the compound exhibiting liquid crystallinity existing in the polymerization region. It is possible to sufficiently align a compound exhibiting liquid crystallinity. On the other hand, for example, when the polymerization rate of the polymerizable compound is slow and a concentration gradient of the compound occurs gently in the polymerized region and the unpolymerized region, the compound exhibiting liquid crystallinity in the film is sufficient. Since it takes time to apply the shear stress, if the moving speed of the boundary is increased, it becomes difficult to orient a compound exhibiting sufficient liquid crystallinity in the vicinity of the boundary. Thus, “the speed at which a compound exhibiting liquid crystallinity is aligned” refers to the type of compound exhibiting liquid crystallinity, the type of compound that diffuses and moves, the type of compound formed by polymerization (polymerized product), and the polymerization conditions. It may be determined so that the orientation is appropriately generated according to the above, and the setting of the speed can be appropriately changed.

Moreover, it is preferable to set it as 1 * 10 < ^-7 > -4 * 10 < ^-1 > m / s as a speed | rate (moving speed which moves the said boundary) that such a compound which shows liquid crystallinity aligns, 1 *. It is more preferable to set it as 10 ^{< -6} > ^-4 * 10 ^<-2 > m / s. When such a rate is less than the lower limit, the polymerization reaction proceeds faster than the diffusion of the compound, so that the diffusion transfer of the compound is suppressed by increasing the viscosity, and the shear stress is sufficiently applied to the compound exhibiting liquid crystallinity. Tends to become difficult to orient in a wide range, and on the other hand, if the upper limit is exceeded, the speed becomes too high, and the compound can sufficiently diffuse and move in the vicinity of the boundary. It becomes difficult and it tends to be difficult to form an orientation in the polymerization region. Also, when using the one of the compounds C11~17 as the polymerizable material, the polymerization of the polymerizable material, employing a photopolymerization method for irradiating an intensity of 0.1μW ^/ cm ² ~30mW ^/ cm 2 In some cases, the speed at which the compound exhibiting liquid crystallinity is aligned (moving speed for moving the boundary) is 1 × 10 ⁻⁷ to from the viewpoint that an alignment film can be efficiently formed. It is preferable to set to 4 × 10 ⁻¹ m / s.

  In addition, the method of continuously moving the boundary of the region toward the unpolymerized region is not particularly limited. For example, when the polymerization method is thermal polymerization, the heating region is continuously connected to the unpolymerized region. It is only necessary to adopt a method that can be moved in an appropriate manner, and when the polymerization method is photopolymerization, the light irradiation region may be continuously moved to an unirradiated region. Any possible method may be adopted as appropriate.

  In addition, as a method of continuously moving the boundary of such a region toward an unpolymerized region, the moving speed of the boundary can be controlled more easily, and an alignment region can be formed more efficiently. From the above, in order to perform polymerization of the polymerizable material by photopolymerization, and to continuously move the boundary toward the unpolymerized region, the boundary of the light irradiation region is directed toward the unirradiated region of light. It is preferable to employ a method of continuous movement. Further, the method of continuously moving the boundary of the light irradiation region toward the non-irradiated region is not particularly limited as long as it is a method capable of moving the boundary. A method of continuously moving a light source itself that can irradiate light only to a part of a region made of a material, or a film of the polymerizable material continuously while fixing the light source A method of moving, a method of continuously moving a photomask using a photomask, and a method of continuously moving a film of the polymerizable material while fixing the photomask using a photomask May be.

  Further, among the methods of continuously moving the boundary of the light irradiation region toward the light non-irradiation region, using the photomask during the photopolymerization, the photomask and / or the A method of continuously moving the film (for example, using a photomask and continuously moving the photomask, or using a photomask and fixing the photomask while continuously coating the polymerizable material film) It is preferable to adopt a method such as a moving method. In this way, by adopting photopolymerization for the polymerization of the polymerizable material, by using a photomask, it is possible to continuously move the boundary of the light irradiation region toward the light non-irradiated region, It can be achieved more easily.

  Here, referring to FIGS. 1 to 4 for a preferred embodiment of the method for producing an oriented film of the present invention when the polymerizable material is polymerized by photopolymerization and a photomask is used for the photopolymerization. And explain briefly. In the preferred embodiment shown in FIGS. 1 to 4, first, light is shielded between the film 13 and the light source 11 so that only a part of the film 13 is irradiated with light from the light source 11. After disposing a possible photomask 14 (FIG. 1), polymerization of the polymerizable material is started from a partial area A1 of the film 13 by irradiating light from the light source 11 (see FIG. 2). By continuously moving the photomask 14 at such a speed that the compound exhibiting the property is aligned, the boundary S of the polymerization region is directed toward the unpolymerized region A2 at such a rate that the compound exhibiting the liquid crystallinity is aligned ( By moving continuously (in the direction of arrow A) (see FIGS. 3 to 4), an oriented film is obtained. Thus, when photopolymerization is used for the polymerization of the polymerizable material, the boundary S between the polymerized region and the unpolymerized region can be moved by a simple method such as a method of moving the photomask 14. It is possible to manufacture the oriented film more efficiently. In addition, although preferred embodiment of the manufacturing method of the orientation film of this invention when utilizing a photomask was described with reference to FIGS. 1-4, when the orientation film of this invention in the case of utilizing a photomask, it is. The embodiment of the manufacturing method is not limited to the above embodiment. For example, in the embodiment shown in FIGS. 1 to 4 described above, a method of moving the photomask 14 is adopted to move the boundary S between the overlapped region and the unpolymerized region. A method of moving the film 13 itself may be employed. In the embodiment shown in FIGS. 1 to 4, the polymerization of the polymerizable material is started after the light is applied to a part of the region R <b> 1 of the film 13. The polymerization method that can be employed in the method for producing an oriented film is not limited to the method employed in such an embodiment. For example, the entire film is covered with a photomask, and the liquid crystallinity is exhibited along with the start of light irradiation. The photomask or film is continuously moved at such a speed that the compound showing the orientation is aligned, and the film is introduced into the light irradiation region (exposure portion) at the speed, thereby irradiating the light. Polymerization starts from the area (partial area of the film) introduced into the area (exposed area), and the boundary of the polymerized area moves toward the unpolymerized area at such a speed that the liquid crystalline compound is oriented as it is. Let orientation The method may be employed so as to obtain the beam.

  When the polymerizable material is polymerized by photopolymerization and a photomask is used for the photopolymerization, the orientation direction can be easily controlled according to the edge shape of the photomask. Hereinafter, the control of the orientation according to the edge shape of the photomask will be briefly described with reference to the embodiments shown in FIGS. For example, when a photomask 14 as shown in FIG. 5 is used as a photomask, the compound flows in a direction substantially perpendicular to the boundary S shown in FIG. The orientation direction can be controlled. Further, when a photomask 14 having edges formed in an oblique direction as shown in FIG. 6 is used as a photomask, the flow of the compound is basically in a direction substantially perpendicular to the boundary S shown in FIG. Occurs, when the boundary S is substantially perpendicular to the oblique boundary S, or when the movement speed of the boundary S is high, a vector in the direction of movement of the boundary S (arrow A) and a vector in the direction perpendicular to the boundary S (arrow P) The orientation direction can be controlled in the direction of the vector sum. Therefore, when photopolymerization using a photomask is performed, the orientation direction can be easily controlled in a desired direction according to the edge shape of the photomask. Therefore, in order to form a desired alignment direction, it may be used while appropriately changing the edge shape of the photomask, which makes it possible to easily control the alignment direction.

  When the polymerizable material is polymerized by photopolymerization and a photomask is used for the photopolymerization, a plurality of substantially rectangular openings are used as the photomask, and the long sides of the openings are substantially the same. A photomask formed so as to be parallel can be preferably used. Hereinafter, a preferred embodiment of a photopolymerization method in the case of using a mask in which such a plurality of substantially rectangular openings are formed so that the long sides of each opening are substantially parallel will be described with reference to FIG. This will be briefly described with reference to FIG. 7 and 8 are schematic plan views schematically showing the relationship between the photomask 14 and the substrate 12 when viewed from the light source side (in the optical axis direction of the irradiated light). In these embodiments, the light source, the photomask 14 and the substrate 12 are disposed so that the film disposed on the substrate 12 can be photopolymerized by the light transmitted through the opening 14A. Yes.

  The photomask 14 shown in FIGS. 7 and 8 has a plurality of substantially rectangular openings 14A. Here, the “substantially rectangular shape” means a shape corresponding to a rectangular shape such as the opening portion 14A shown in FIG. 8 is a parallelogram shape in which the angle of the four corners is not 90 degrees as in the opening portion 14A shown in FIG. 8 (in this case, the four corners Includes arc-shaped ones and shapes in which a portion corresponding to a long side or a short side is an arc-shaped side). Thus, the substantially rectangular opening is such that the opening corresponds to a long side (which may be an arcuate side) and a short side (which may be an arcuate side), as in the case of a rectangle. It is an expression intended to be an elongated shape that is longer than the corresponding side.

Such a substantially rectangular shape (elongate shape) of the opening 14A is not particularly limited, and the long side length Y may be longer than the short side length X. In addition, the ratio (Y / X) of the long side length Y to the short side length X is preferably 2.0 or more, and is 5.0 to 2.0 × 10 ⁵ . More preferably.

  Further, the length X of the short side of the opening 14A varies depending on the substrate 12 used in the polymerization, the size of the film, and the like, and cannot be generally described, but is 1 μm to 10 mm. The average value of the length X of the short sides of the plurality of openings 14A is preferably in the same numerical range. When the length X of the short side of the opening 14A is less than the lower limit, the orientation tends to hardly occur. On the other hand, when the upper limit exceeds the upper limit, it is difficult to obtain a film having a uniform in-plane orientation. There is a tendency.

  In addition, in such an opening 14A, the long sides of the openings are arranged substantially in parallel. Thus, by arranging the opening 14A so that the long sides of each opening are substantially parallel, when forming an oriented film in a large area, the orientation direction can be controlled to be uniform. It becomes possible. Moreover, as such a mask having the openings 14A, the openings 14A are preferably formed periodically, and it is more preferable that the openings 14A having the same shape are formed periodically. Thus, when the openings 14A are formed periodically, the pitch of the openings 14A (the distance from the center of one opening to the center of the adjacent opening) is not particularly limited, It is preferably 1 μm to 10 mm, and more preferably 10 μm to 1 mm (note that the average value of the pitch of the plurality of openings 14 </ b> A is preferably in the same numerical range). When the pitch of the openings 14A is less than the lower limit, the orientation tends to be difficult to occur. On the other hand, when the pitch exceeds the upper limit, a film having a uniform in-plane orientation tends to be hardly obtained. Note that in such a photomask having a plurality of openings, the number of openings may be two or more and is not particularly limited, and the design may be changed as appropriate depending on the size of the mask and the substrate. it can.

  Using such a mask 14 having a plurality of rectangular openings formed substantially in parallel, for example, the substrate 12 is formed on the substrate while moving the substrate 12 in the direction opposite to the direction A or in the same direction. When light polymerization is performed on the film by irradiating light through the opening 14A, a boundary of a polymerization region is formed for each opening 14A, and each boundary is continuously directed toward an unpolymerized region. Thus, it is possible to form an alignment region for each opening 14A. Therefore, when using a mask 14 in which a plurality of rectangular openings are formed substantially in parallel, the mask and / or film is moved by the same length as the interval (distance) between adjacent openings, An alignment region can be formed in a large area, and an alignment film can be formed efficiently.

  Further, in the case of using the mask 14 in which such a plurality of rectangular openings are formed substantially in parallel, the orientation direction can be controlled according to the shape of the edge of the opening 14A. In the embodiment shown in FIG. 7, when the photopolymerization is performed while moving the substrate 12 on which the film (not shown) is formed in the direction opposite to the direction A (or the same direction), the orientation direction Can be controlled in a direction perpendicular to the long side of the opening 14A. Further, in the embodiment shown in FIG. 8, for example, the substrate 12 on which the film (not shown) is formed is moved in the direction opposite to the direction A (the boundary S is thereby indicated by the arrow A in the figure). When the photopolymerization is performed (while continuously moving in the direction of 2), the edge of the opening 14A is formed obliquely with respect to the two sides of the substrate 12 when viewed from the light source side. When the polymerization causes a compound flow in a direction substantially perpendicular to the long side of the opening 14A and the movement of the substrate 12 is fast or substantially perpendicular to the long side, or the movement direction of the boundary S The orientation direction can be controlled in the direction of the vector sum of the vector and the vector in the direction substantially perpendicular to the long side of the opening 14A. In addition, although the photopolymerization method which can be suitably employ | adopted for this invention was demonstrated with reference to FIGS. 7-8, the photopolymerization method which can be employ | adopted in this invention is limited to these methods. Is not to be done. For example, although the method of moving the substrate 12 has been described in the above-described embodiment, photopolymerization may be performed by appropriately adopting a method of fixing the substrate 12 and moving the mask and the light source.

  Further, in the present invention, after the polymerization of the polymerizable material is started from a partial region of the film made of the polymerizable material, the region having a liquid crystallinity existing in the film is oriented at a speed such that the region is aligned. An oriented film is manufactured by continuously moving the boundary toward an unpolymerized region, and a film subjected to pre-polymerization as a film made of a polymerizable material used for manufacturing such an oriented film. May be used. By using such a pre-polymerized film, it becomes possible to form a sufficiently oriented structure even if the speed of continuously moving the boundary of the polymerization region toward the unpolymerized region is increased. There is a tendency that an oriented film can be formed more efficiently in a large area. As used herein, “preliminary polymerization” means that the film of the polymerizable material is slightly polymerized to such an extent that the fluidity of the polymerizable compound is not impaired (for example, photopolymerization is performed for both prepolymerization and main polymerization). When using, the polymerizable compound in the film is slightly polymerized to such an extent that the fluidity is not impaired by irradiating the film of the polymerizable material with light having a lower intensity than the main polymerization. Say.

  Thus, in the present invention, from the viewpoint of forming an oriented film in as short a time as possible by increasing the speed of continuously moving the boundary of the polymerization region toward the unpolymerized region, after pre-polymerization These films can be suitably used. Such a prepolymerization method is not particularly limited. For example, when photopolymerization is employed for the prepolymerization, even if the prepolymerization is performed using a photomask, the photomask is not used. It may be a preliminary polymerization. Thus, the preliminary polymerization is, for example, preliminary polymerization by photopolymerization using a photomask in which a plurality of substantially rectangular openings are formed so that the long sides of each opening are substantially parallel. There may be.

During such preliminary polymerization, when using the photopolymerization, it is preferable to irradiate light at an intensity of ^{0.001μW / cm 2 ~10mW / cm 2} , 0.05μW / cm 2 ~1mW / cm More preferably, the light is irradiated with an intensity of ² . If the illuminance of light is less than the lower limit, the reaction tends to be inadequate and the effect of prepolymerization tends to be difficult to obtain. On the other hand, when the upper limit is exceeded, polymerization of the polymerizable compound proceeds excessively, resulting in the polymerization. After the polymerization of the polymerizable material (polymerization of the polymerizable compound) is started from a partial region of the film made of the polymerizable material, the liquid crystal compound existing in the film is aligned at a speed at which the compound is aligned. Even if the boundary is continuously moved toward the unpolymerized region, the compound is not sufficiently diffused and the oriented film tends to be not obtained. In addition, when adopting photopolymerization at the time of such prepolymerization, the photopolymerization conditions are the same as the photopolymerization conditions described as the polymerization method of the polymerizable material, except for the conditions relating to the illuminance of the light. Conditions can be adopted.

  In this way, in the present invention, after the polymerization of the polymerizable material is started from a partial region of the film using the film made of the polymerizable material, the liquid crystal properties existing in the film are exhibited. By continuously moving the boundary of the region toward the unpolymerized region at such a speed that the compound is oriented, it is possible to obtain an oriented film. In the method for producing an oriented film of the present invention, a kind of shear stress generated by a compound (the monomer and / or the polymer) that moves from an unpolymerized region to a polymerized region in the film after polymerization is started is used. Since the compound (the monomer and / or the polymer) exhibiting liquid crystallinity existing in the film is aligned, basically, the compound moves in a direction (perpendicular to the boundary of the region). The orientation direction can be controlled, and when polymerization is performed by photopolymerization, the orientation can be controlled in various directions according to the shape of the mask and the pattern orientation can be changed depending on the location. . In the present invention, as the polymerizable compound, a film made of a polymerizable material containing only one type of polymerizable compound (monomer) exhibiting liquid crystallinity at least one of before polymerization and after polymerization is used. Is a method that makes it possible to obtain an orientation film by increasing the orientation region with movement while forming the orientation by moving the boundary of the polymerization region (in the case where only one kind of polymerizable compound is used). The present inventors presume that the orientation can be formed because the diffusion phenomenon of the substance can be utilized by moving the boundary of the polymerization region even if it exists.

  Further, in the present invention, after the polymerization of the polymerizable material is started from a partial region of the film made of the polymerizable material, the region having a liquid crystallinity existing in the film is oriented at a speed such that the region is aligned. The alignment film is manufactured by continuously moving the boundary of the region toward the unpolymerized region, but the boundary of the region is continuously moved toward the unpolymerized region, so that the alignment region is formed in the film. In order to complete the polymerization reaction of the polymerizable material or to fully cure the orientation film, for example, the film may be allowed to stand under a temperature condition where the polymerization further proceeds. Good. In addition, in order to more efficiently polymerize the unpolymerized component (polymerizable compound) remaining in the alignment region, light irradiation, temperature conditions, etc. are appropriately performed under conditions that can maintain the formed alignment state. For example, a process for further progressing the polymerization may be performed. As described above, in the present invention, the orientation is formed by utilizing the diffusion phenomenon of the substance while moving the boundary of the polymerization region, but it is necessary to completely polymerize the components in the film in the polymerization process accompanying the movement of the boundary. Rather, after continuously moving the boundary of the region toward the unpolymerized region, while maintaining the orientation structure, the step of further proceeding the polymerization (post-polymerization step), Finally, an oriented film having an oriented structure fixed may be obtained. The conditions for such a post-polymerization step are not particularly limited, and may be carried out while appropriately changing depending on the type of components in the polymerizable material to be used.

  Moreover, in the manufacturing method of the orientation film of this invention, it is possible to manufacture a long orientation film by a roll-to-roll by using a long board | substrate film etc. for a board | substrate.

  Thus, the orientation film obtained by the method for producing an orientation film of the present invention can be a film in which the orientation of the compound exhibiting liquid crystallinity is formed in a large area. It can be used as a retardation film for use in a display (LCD), a retardation film for use in an antireflection circularly polarizing plate of an organic EL display, or a 3D pattern retardation film.

  EXAMPLES Hereinafter, although this invention is demonstrated more concretely based on an Example, this invention is not limited to a following example.

(Synthesis Example 1: Synthesis of A6CB and its homopolymer)
<Synthesis of A6CB and its characteristic evaluation>
4- (6-acryloyloxyhexyloxy) -4′-cyanobiphenyl (A6CB) was synthesized by the method shown below. That is, 4-cyano-4′-hydroxybiphenyl (100 mmol) was dissolved in 120 mL of N, N-dimethylformamide (DMF) to obtain a solution. Next, 1-bromohexanol (110 mmol), potassium carbonate (110 mmol), and potassium iodide (amount of catalyst: 1 mmol with respect to 1 mol of calcium carbonate) were added to the solution, and the mixture was heated and stirred at 100 ° C. for 5 hours. . Next, the heating and stirring was stopped to complete the reaction, and the obtained reaction solution was extracted with ethyl acetate, and the formed organic layer was washed with 1N hydrochloric acid and saturated brine in this order. Next, the washed organic layer was dried over anhydrous magnesium sulfate, the desiccant was removed by filtration, and the solvent was distilled off under reduced pressure. Thereafter, the target product (4-cyano-4 ′-(6-hydroxyhexyloxy) biphenyl) is separated and purified by silica gel chromatography, and then recrystallized from chloroform and hexane to give a white solid compound A (4-cyano-). 21.3 g (72 mmol) of 4 ′-(6-hydroxyhexyloxy) biphenyl) was obtained.

  Next, after compound A (50 mmol), triethylamine 20.7 mL (150 mmol), and THF 30 mL were mixed in an eggplant flask, hydroquinone (amount of catalyst: ratio of 2 mmol to 1 mol of the compound) was added to obtain a mixture. The eggplant flask was submerged in a 23 ° C. water bath, and the atmosphere inside the eggplant flask was changed to a nitrogen atmosphere. Then, acryloyl chloride (150 mmol) was slowly added dropwise to the mixture with stirring in a nitrogen atmosphere. Got. After stirring in this manner for 48 hours under a nitrogen atmosphere, 300 mL of a saturated aqueous sodium hydrogen carbonate solution was added to the reaction solution, followed by further stirring for 30 minutes. Thereafter, the obtained reaction solution was extracted with chloroform, and the organic layer was washed with 1N hydrochloric acid and saturated brine in this order. Subsequently, the solvent was distilled off from the obtained organic layer under reduced pressure at room temperature, and the target product (4- (6-acryloyloxyhexyloxy) -4′-cyanobiphenyl) was separated and purified by silica gel chromatography, and then re-reacted with methanol. By crystallizing, 9.8 g (28 mmol) of 4- (6-acryloyloxyhexyloxy) -4′-cyanobiphenyl was obtained. In addition, when the structure of the compound thus obtained was confirmed by NMR and IR measurement, it was 4- (6-acryloyloxyhexyloxy) -4′-cyanobiphenyl represented by the following general formula (2). It was confirmed.

  The 4- (6-acryloyloxyhexyloxy) -4'-cyanobiphenyl thus obtained is a compound having a rigid cyanobiphenyl structure as a mesogen, as is clear from the above formula (2). Moreover, using a differential scanning calorimeter (DSC 6220 manufactured by DSC SII NanoTechnology), the temperature was raised and lowered at a rate of 1 ° C./min to give 4- (6-acryloyloxyhexyloxy) -4′-cyanobiphenyl. As a result of confirming the behavior of the liquid crystal phase, the liquid crystal phase is not shown, and the phase transition from the crystal layer to the isotropic phase is 69 ° C. during the temperature rising process, and the phase is changed from isotropic phase to crystallinity at 53 ° C. Phase transition.

<Synthesis of A6CB homopolymer and evaluation of its properties>
After adding 15 mmol of 4- (6-acryloyloxyhexyloxy) -4′-cyanobiphenyl obtained as described above into 35 mL of N, N-dimethylformamide (DMF), an additional 0.75 mmol of Azobisisobutyronitrile (AIBN) was added as a thermal polymerization initiator, and the mixture was stirred at a temperature of 70 ° C. for 6 hours to allow the reaction to proceed to obtain a polymerization solution. Next, the polymerization solution after completion of the reaction was put into 0.5 L of methanol to precipitate a polymer, washed again in 0.5 L of methanol, and then filtered to obtain a solid content. Subsequently, the obtained solid content was vacuum-dried at room temperature (25 ° C.) for 24 hours to obtain 4.7 g of a polymer (A6CB homopolymer).

  When GPC measurement was performed on the polymer thus obtained, it was confirmed that the number average molecular weight Mn of the polymer was 8000 g / mol when converted to polystyrene standards. Further, when the polymer was subjected to differential scanning calorimetry using a differential scanning calorimeter (DSC), it exhibited a glass transition temperature at 38 ° C. in the temperature rising process, liquid crystallinity at 38 to 126 ° C., and 124 to 124 in the temperature decreasing process. The liquid crystallinity was exhibited up to 29 ° C, and the glass transition temperature was exhibited at 29 ° C. From these results, it was found that 4- (6-acryloyloxyhexyloxy) -4'-cyanobiphenyl obtained in Synthesis Example 1 is a compound exhibiting liquid crystallinity after polymerization.

Example 1
First, using 4- (6-acryloyloxyhexyloxy) -4′-cyanobiphenyl (A6CB: 1 functional acrylate) obtained in Synthesis Example 1 as a polymerizable compound (monomer), the polymerizable compound is , Irgacure 651 (manufactured by BASF) as a photopolymerization initiator was added at a ratio of 1 mol%, and the resulting mixture was once dissolved in dichloromethane, and then the solvent was distilled off to obtain a polymerizable compound. A polymerizable material containing only A6CB (only one type) was prepared.

  Next, two soda glass substrates each having a size of 25 mm square and a thickness of 1.1 mm are mixed with epoxy adhesive mixed with silica particles having a diameter of 2 μm on the left and right ends (two parallel sides) of the glass substrate. A glass cell having a cell thickness of 2 μm was applied by applying and adhering them with a length of 25 mm and a width of 2.5 mm (the adhesive also functions as a spacer. The portions not applied with the adhesive were used as openings). did. The soda glass substrate used was subjected to UV ozone treatment after ultrasonic cleaning in the order of neutral detergent, ion-exchanged water, acetone and isopropanol.

Next, after the glass cell was placed on a hot stage (trade names “FP-90, FP-82HT” manufactured by METTLER TOLEDO), one of the glass cells was melted while the polymerizable material was melted at 100 ° C. After injecting a polymerizable material into the glass cell by capillary action from the opening, a polymer material film (film size: length 20 mm, width 20 mm, thickness 2 μm) is maintained at 100 ° C. for 10 minutes. Obtained. Next, a photomask having a square shape with a length of 30 mm and a width of 30 mm was fixedly disposed so as to cover the entire film in the glass cell (so that the film enters the light shielding portion). In addition, the light source was arranged at a position where the entire surface of the film was irradiated with light if there was no mask. Next, light irradiation is started from a light source, and while the light is irradiated, the mask is moved at 20 μm / s to gradually form a light irradiation region on the film, thereby exposing an exposure unit (light irradiation unit). The polymerization is started from a partial region of the film introduced into (2), and the mask is continuously moved at 20 μm / s, so that the boundary between the light irradiation region and the light non-irradiation region is set to 20 μm / second. The photopolymerization was carried out under a temperature condition of 100 ° C. (heating condition) by continuing the movement at s. Here, the process of moving such a mask will be described with reference to FIG. 5. The exposure area A1 on the soda glass substrate 12 of the cell before moving the mask 14 is a rectangular area of 5 mm in length and 25 mm in width. (This region is a region of 5 mm vertically from the opening on the side where the polymerizable material is not injected, and the film does not exist in the region. The direction of movement of the mask is the direction perpendicular to the boundary S of the light irradiation area A1, as shown in FIGS. 5A to 5B (the arrow in the figure). (Direction shown in A). FIG. 5 is a schematic plan view schematically showing a state in which the substrate and the photomask are viewed from the light source side (the optical axis direction of light to be irradiated). In such photopolymerization, a high-pressure mercury lamp (trade name “SX-UI501HQ” manufactured by Ushio Inc.) is used as a light source, and a colored glass filter (manufactured by AGC Techno Glass Co., IRA-265, UV-D54C, ND) is used. (90%) and ND (40%) were used in combination and irradiated with ultraviolet light having an illuminance of 1.0 mW / cm ² (peak wavelength: 366 nm). In this way, polymerization is started from a partial region using a mask, the polymerizable material is polymerized while moving the boundary between the polymerized region and the unpolymerized region, and the entire region of the film-like polymerizable material is obtained. The photopolymerization was performed by irradiating light. Moreover, after performing such photopolymerization, the said glass cell was left still for 10 minutes on 100 degreeC temperature conditions, and superposition | polymerization of the polymeric compound in the said film | membrane was further advanced (post-polymerization process). After performing such a post-polymerization step, the glass cell was taken out from the hot stage to obtain a film (transparent uncolored, thickness after curing: 1.7 μm) formed in the glass cell.

  In order to confirm the characteristics of the film thus obtained, the glass cell was inserted between two orthogonally arranged polarizing plates and observed while rotating the glass cell. And it was confirmed that the obtained film was an orientation film oriented almost uniformly in an area of about 20 mm square. The dark field direction was parallel or perpendicular to the absorption axes of the two polarizing plates arranged orthogonally (lightness and darkness appeared every 45 ° by the rotation of the cell). Further, when the orientation state was confirmed using a polarizing microscope (trade name “BX50” manufactured by Olympus Corporation), the obtained film was uniformly oriented, and the orientation was confirmed even in a minute region.

  Next, in order to confirm the orientation direction of the compound in the obtained film, an absorption spectrum (A⊥) in a direction perpendicular to the mask edge of the photomask and an absorption spectrum in a direction parallel to the mask edge of the photomask ( A //) was measured. For the absorption spectrum measurement, an ultraviolet-visible spectrophotometer (V-650ST manufactured by JASCO Corp.) was used, and the polarization direction was adjusted using a Grand Taylor prism.

From the measurement results of the absorption spectrum, it was found that the absorption spectrum (A⊥) in the direction perpendicular to the mask edge of the photomask has a higher absorbance than the absorption spectrum (A //) in the parallel direction. Further, from the measurement result of such an absorption spectrum, the order parameter S representing the degree of orientation of the molecule is calculated by the following calculation formula (1):
S = (A⊥−A //) / (A⊥ + 2A //) (1)
[Where A⊥ represents the intensity of the absorption spectrum in the vertical direction, and A // represents the intensity of the absorption spectrum in the parallel direction. ]
As a result, the order parameter S showed a very large value of 0.22. The order parameter S was obtained from the average value after obtaining the order parameter S for each wavelength from the absorbance (A) data in increments of 1 nm between the measurement wavelengths of 330 nm and 345 nm.

  From the above results, in the film obtained in Example 1, the compound having liquid crystallinity (polymer of A6CB) was aligned in a direction perpendicular to the mask edge (boundary S in FIG. 5) of the photomask. I found out. Furthermore, when retardation Δnd was confirmed using a Belek compensator (Olympus U-CBE), Δnd for light having a wavelength of 546 nm was 130 nm. In addition, when birefringence (DELTA) n was calculated and calculated | required from the relationship with the thickness of the film after hardening, (DELTA) n with respect to the light of wavelength 546nm was 0.076. The obtained results are shown in Table 1.

  As is clear from the results as described above, in the film obtained in Example 1, it was confirmed that an orientation film uniformly oriented over almost the entire polymerization region was formed. According to the method for producing an oriented film of the invention, an oriented film in which an oriented region is formed in a large area while using a polymerizable material containing only one compound as the polymerizable compound as the oriented film material. It has been found that it is possible to produce

  As described above, according to the present invention, an orientation film in which an orientation region is formed in a large area while a polymerizable material containing only one kind of compound is used as a material for the orientation film. It becomes possible to provide the manufacturing method of the orientation film which enables it to manufacture efficiently. As described above, the method for producing an orientation film according to the present invention is a particularly excellent method in that an orientation region can be formed in a large area. For example, the orientation film can be used for a polarizing plate or a liquid crystal display (LCD). It is useful as a method for producing an alignment film for use as a retardation film, a retardation film for use in an antireflection circularly polarizing plate for organic EL displays, a 3D pattern retardation film, and the like.

  11: light source, 12: substrate, 13: film made of polymerizable material, 14: photomask, 14A: opening, X: length of short side of opening 14A, Y: length of long side of opening 14A , S: boundary of the polymerization region, A: arrow conceptually indicating the direction in which the boundary S of the polymerization region is moved, P: arrow conceptually indicating the direction perpendicular to the boundary S of the polymerization region, L: irradiated from the light source Light, A1: region irradiated with light (polymerized region: exposed portion), A2: unpolymerized region not irradiated with light (unpolymerized region: light-shielding portion), A3: orientation formed Area.

Claims (7)

As a polymerizable compound, using a film made of a polymerizable material containing only one type of polymerizable compound exhibiting liquid crystallinity before and / or after polymerization,
After the polymerization of the polymerizable material is started from a partial region of the film, the boundary of the region is continuously directed toward the unpolymerized region at such a speed that the liquid crystalline compound existing in the film is oriented. A method for producing an oriented film, characterized in that an oriented film is obtained by moving the film.   In order to perform polymerization of the polymerizable material by photopolymerization and continuously move the boundary toward the unpolymerized region, the boundary of the light irradiation region is continuously directed toward the non-irradiated region. The method for producing an oriented film according to claim 1, wherein   A photomask is used during the photopolymerization, and the photomask and / or the film is continuously moved to move the boundary of the light irradiation region toward the unirradiated region. The manufacturing method of the orientation film of Claim 2 characterized by the above-mentioned.   The orientation film according to claim 3, wherein the photomask is a mask in which a plurality of substantially rectangular openings are formed such that the long sides of each opening are substantially parallel. Method.   The method for producing an oriented film according to claim 1, wherein a prepolymerized film is used as the film made of the polymerizable material. The method for producing an oriented film according to any one of claims 1 to 5, wherein a speed of moving the boundary is 1 × 10 ⁻⁷ to 4 × 10 ⁻¹ m / s. The polymerizable compound is represented by the following general formula (1):
^{Z 1 p-M 1 -L 1} - (M 2 -L 2) q-M 3 -Z 2 r (1)
Embedded image and in the formula, Z ¹ , Z ² , M ¹ , M ² , M ³ , L ¹ , L ² , p, q, r are respectively the following compounds C11 to C17 [in compound C11: Z ¹ and Z ² in the formula (1) may be the same or different, and each is a group represented by the formula: -L ³ -S ¹ -F ¹ , and F ¹ is an acryl group and a methacryl group. Any one of the groups, S ¹ is any ^one of a single bond and a linear alkylene group having 1 to 12 carbon atoms, and L ³ is any one of a single bond, an ether group, an ester group, and a carbonate group. Any one, p is 1, M ¹ is a 1,4-phenylene group, L ¹ is any ^one of a single bond and —COO—, q is 0, and M ³ is 1 , 4-phenylene group and r is 1.
In the compound C12, Z ¹ and Z ² in the formula (1) may be the same or different, and each is a group represented by the formula: -L ³ -S ¹ -F ¹ , and F ¹ is acrylic Any one of a group and a methacryl group, S ¹ is any ^one of a single bond and a linear alkylene group having 1 to 12 carbon atoms, and L ³ is a single bond, an ether group, an ester group, and a carbonate group. P is 1, M ¹ is a 1,4-phenylene group, L ¹ is —COO—, M ² is a 1,4-phenylene group, and L ² is -OCO-, q is 1, M ³ is a 1,4-phenylene group, and r is 1.
In the compound C13, Z ¹ and Z ² in the formula (1) may be the same or different, and each is a group represented by the formula: -L ³ -S ¹ -F ¹ , and F ¹ is acrylic Or a methacryl group, S ¹ is a group represented by the formula: (CH ₂ CH ₂ O) z (z is any one of 2 and 3), and L ³ is A single bond, p is 1, M ¹ is a 1,4-phenylene group, L ¹ is either a single bond or an ester group, q is 0, and M ³ is 1,4- A phenylene group and r is 1,
In compound C14, Z ¹ in formula (1) is a group represented by the formula: -L ³ -S ¹ -F ¹ , F ¹ is ^one of an acrylic group and a methacryl group, and S ¹ is A single bond, L ³ is a single bond, p is 1, M ¹ is a 1,4-phenylene group, L ¹ is a single bond, q is 0, M ³ is 1, 4-phenylene group, Z ² is one selected from a hydrogen atom, a halogen atom, a cyano group, a nitro group, an alkyl group having 1 to 12 carbon atoms and an alkoxy group having 1 to 12 carbon atoms, And r is 1,
In compound C15, Z ¹ in formula (1) is a group represented by the formula: -L ³ -S ¹ -F ¹ , F ¹ is any one of an acryl group and a methacryl group, and S ¹ is A linear alkylene group having 1 to 12 carbon atoms, L ³ is an ether group, p is 1, M ¹ is a 1,4-phenylene group, L ¹ is a single bond, and q is 0 M ³ is a 1,4-phenylene group, Z ² is a hydrogen atom, a halogen atom, a cyano group, a nitro group, an alkyl group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms. One selected, and r is 1,
In Compound C16, Z ¹ in Formula (1) is a group represented by the formula: -L ³ -S ¹ -F ¹ , F ¹ is any one of an acryl group and a methacryl group, and S ¹ is A group represented by the formula: (CH ₂ CH ₂ O) z (z is any one of 2 and 3), L ³ is a single bond, p is 1, M ¹ is 1 , 4-phenylene group, L ¹ is a single bond, q is 0, M ³ is a 1,4-phenylene group, Z ² is a hydrogen atom, a halogen atom, a cyano group, a nitro group, carbon One selected from an alkyl group having 1 to 12 carbon atoms and an alkoxy group having 1 to 12 carbon atoms, and r is 1.
In compound C17, Z ¹ in formula (1) is a group represented by the formula: -L ³ -S ¹ -F ¹ , F ¹ is ^one of an acryl group and a methacryl group, and S ¹ is A linear alkylene group having 1 to 12 carbon atoms, L ³ is an ether group, p is 1, M ¹ is a 1,4-phenylene group, L ¹ is —COO—, and q is 0, M ³ is a 1,4-phenylene group, and Z ² is a hydrogen atom, a halogen atom, a cyano group, a nitro group, an alkyl group having 1 to 12 carbon atoms, or an alkoxy group having 1 to 12 carbon atoms. And r is 1. At least one compound selected from the group consisting of:
The manufacturing method of the orientation film as described in any one of Claims 1-6 characterized by these.