JP4909166B2 - Planarizing sheet and color filter manufacturing method using the same - Google Patents

Abstract

A planar sheet having sequentially laminated layer including a mold releasing layer, a substrate layer and a elastic layer, wherein the surface tension of contacting region of the mold releasing layer (23 DEG C) is smaller than or equal to 30 mN/m and the arithmetic mean roughness of the mold releasing layer in roughness curves Ra is smaller than or equal to 20 nm. The arithmetic mean roughness of the substrate layer adjacent to the mold releasing layer Ra is smaller than or equal to 50 nm. The elastic ratio of the elastic layer (23 DEG C) is between 0. 5 MPa to 20 MPa and the thickness of the elastic layer is between 0. 1mm to 0. 5 mm. The planar sheet is used to planarize a transparent resin layer and prevent transparent ink forming the transparent resin layer from transferring back during printing such that it is difficult for the transparent resin layer to have defect du to the mixing of particles. A fabricating method for color filter using the planar sheet is also provided.

Description

  The present invention provides an outer peripheral surface of a roller used for producing a color filter by rolling on the surface of a transparent resin layer formed on a substrate and colored at least in part to flatten the surface. The present invention relates to a flattening sheet that forms a contact surface of the roller that is in direct contact with the surface of a transparent resin layer, and a method of manufacturing a color filter using the flattening sheet.

  A color filter used in a flat panel display such as a liquid crystal display (LCD) has red (R), green (G), and blue (B) pixels constituting the liquid crystal display on a transparent substrate. A stripe pattern made of transparent ink colored in each color corresponding to the above is printed by regularly arranging each pixel to form a transparent resin layer.

  However, the transparent ink colored in each color is formed by printing by various printing methods. The stripe pattern of each color has a low surface at both ends of the stripe due to the surface tension of the transparent ink. Therefore, the surface of the transparent resin layer as an aggregate of stripe patterns of each color has an uneven shape corresponding to the protruded shape of the stripe pattern, and light is diffusely reflected by the unevenness. There has been a problem that the contrast is lowered, and in the case of an LCD, for example, liquid crystal response unevenness occurs. Therefore, various technical studies have been conducted in order to flatten the surface of the transparent resin layer formed on the substrate.

  For example, in Patent Documents 1 and 2, transparent inks such as an electron beam curable type and an ultraviolet curable type are used as the transparent ink that is the basis of the stripe pattern, and each color stripe is formed using the transparent ink. In a state where the surface of the transparent resin layer is flattened by superimposing and pressing a flat pressing member such as a film or a glass substrate on the transparent resin layer formed by printing a pattern, the electron beam Alternatively, it is described that after the transparent ink is cured by irradiating ultraviolet rays, the pressing member is peeled off.

In Patent Document 3, a stripe pattern is formed with a thermosetting transparent ink and thermally cured, and a film as a pressing member is superimposed on the transparent resin layer composed of the stripe pattern of each color. In this state, the surface of the transparent resin layer is flattened by uniformly pressing the film with air pressure.
On the other hand, in Patent Document 4, a roller contact surface, which is a surface of the offset blanket, of a roller used for printing a stripe pattern on the surface of a substrate by a lithographic offset printing method and having an offset blanket wound around the outer peripheral surface. In this state, the surface of the transparent resin layer is flattened by rolling the roller on the surface of the transparent resin layer in a state where it is in contact with the surface of the transparent resin layer after printing. .

Further, in Patent Document 5, after a transparent ink not containing a colorant is printed on the transparent resin layer, a metal roller in which a peripheral surface as a contact surface is subjected to a release treatment is used, as described above. And flattening. Further, in Patent Document 6, a roller having a release treatment applied to an outer peripheral surface as a contact surface, while the transparent ink that is the basis of a stripe pattern is directly supplied to the contact surface, the roller is It is described that, by rolling on a substrate, the supplied transparent ink is printed on the surface of the substrate to form a stripe pattern, and at the same time it is flattened.
JP 62-280804 A Japanese Patent Laid-Open No. 3-156419 JP-A-3-154003 JP-A-2-297502 JP-A-8-75914 Japanese Patent Laid-Open No. 8-234013

In the method of flattening using a flat plate-shaped pressing member described in Patent Documents 1 to 3, when the pressing member is superimposed on the surface of the transparent resin layer, bubbles are likely to remain between the two. When the planarization process is performed without removing the remaining bubbles, there is a problem that the traces of the bubbles remain as defects on the surface of the transparent resin layer after the planarization.
Therefore, for example, in Patent Document 2, a procedure for superposing a glass substrate as a pressing member on the surface of the transparent resin layer is finely defined so that bubbles do not remain. There is a problem that the productivity of the color filter is lowered and the cost is increased because a dedicated apparatus such as that described in the diagram of Document 2 must be used carefully. On the other hand, in the method of flattening using a roller described in Patent Documents 4 to 6, the surface of the transparent resin layer is flattened while sequentially rolling the roller on the transparent resin layer. Therefore, the problem of defects due to remaining bubbles is less likely to occur.

  However, when a roller having the same offset blanket as that used for printing a stripe pattern by the planographic offset printing method described in Patent Document 4 is used as the roller, the offset blanket is transparent from the plate. Considering that ink can be well received and transferred to the surface of the substrate, the surface of the roller contact surface has characteristics such as wettability to transparent ink and overall flexibility. Therefore, when flattening, the transparent ink forming the transparent resin layer is reversely transferred to the surface of the offset blanket, and the transparent resin layer is likely to cause defects such as recesses or the transparent resin layer is easily destroyed. In addition, there is a problem that it is difficult to uniformly flatten the entire transparent resin layer.

  In addition, in the case where a metal roller or the like whose contact surface is released as described in Patent Documents 5 and 6 is used, the metal roller or the like is conversely too hard, resulting in variations in the thickness of the transparent resin layer. Since it cannot respond flexibly, there is a problem that it is difficult to uniformly flatten the entire transparent resin layer. In addition, the metal roller or the like has to be replaced when the release process of the contact surface is deteriorated and the transparent ink forming the transparent resin layer is easily reverse-transferred to the contact surface. There was also a problem.

Therefore, the inventor configures the contact surface of the roller, and the contact surface is excellent in the property of preventing the reverse transfer of the transparent ink forming the transparent resin layer, and the transparent resin layer is formed as a whole. It was examined that a flattened sheet having an appropriate flexibility suitable for flattening is wound around the outer peripheral surface of the roller in a replaceable manner and used for flattening.
However, the flattening sheet has the same configuration as that of the conventional offset blanket, and only finely adjusts the characteristics such as the wettability with respect to the transparent ink and the flexibility as a whole of the surface serving as the contact surface of the roller. In particular, when a flattened sheet is wound around and fixed to the outer peripheral surface of the roller, when the foreign object is sandwiched between the two, the shape of the foreign object is changed to the surface of the flattened sheet. It has been found that defects such as recesses corresponding to the protrusions are likely to occur in the transparent resin layer that has been manifested and flattened as protrusions.

  The object of the present invention is to uniformly flatten the entire transparent resin layer, to prevent the transparent ink forming the transparent resin layer from being reversely transferred, and to prevent defects in the transparent resin layer due to the inclusion of foreign matter. An object of the present invention is to provide a flattened sheet that is less likely to cause the problem. Moreover, the objective of this invention is providing the manufacturing method of the color filter using the said planarization sheet | seat.

The planarizing sheet of the present invention integrally forms a release layer, a base material layer, and an elastic layer in order from the outer surface constituting the contact surface of the roller to the inner surface contacting the outer peripheral surface of the roller. The release layer of the base material layer has a surface tension (23 ° C.) of 30 mN / m or less and an arithmetic mean roughness Ra of the roughness curve of 20 nm or less. The arithmetic mean roughness Ra of the roughness curve of the side surface is 50 nm or less, and the elastic modulus (23 ° C.) of the elastic layer is in the range of 0.5 to 20 MPa and the thickness is in the range of 0.1 to 5 mm. It is characterized by this.

According to the present invention, of the layers stacked in order from the outer surface constituting the contact surface of the roller to the inner surface contacting the outer peripheral surface of the roller, the surface of the release layer of the surface that becomes the contact surface of the roller By setting the surface tension (23 ° C.) within the above range, it is possible to prevent reverse transfer of the transparent ink forming the transparent resin layer. Further, the substrate layer, a surface of the release layer side, an arithmetic mean roughness R _a of a roughness curve, as well as the above range, the release layer formed on the surface, the contact surface of the roller and a surface formed, the arithmetic mean roughness R _a of a roughness curve, by the above range, to improve the surface smoothness of the releasing layer, the surface of the transparent resin layer is planarized, Smoothness can be improved.

  Moreover, according to the present invention, by setting the elastic modulus (23 ° C.) and thickness of the elastic layer within the above-mentioned ranges, the appropriate level suitable for flattening the transparent resin layer on the entire flattening sheet. When a flattening sheet is wound around and fixed to the outer peripheral surface of the roller and the foreign matter is caught between the two, the shape of the foreign matter is absorbed and flattened. It is possible to prevent the surface of the sheet from appearing as protrusions and to prevent defects such as recesses corresponding to the protrusions from occurring in the flattened transparent resin layer.

The release layer preferably has a thickness of 30 μm or less. If the thickness of the release layer is within the above range, the effect of imparting appropriate flexibility suitable for flattening the transparent resin layer to the entire flattening sheet can be further improved. The base material layer preferably has a tensile modulus (23 ° C.) of 100 MPa or more and a thickness of 50 to 500 μm.
If the tensile elastic modulus (23 ° C.) of the base material layer is within the above range, the tensile strength in the surface direction of the flattened sheet is improved, and the flattened sheet is applied to the outer peripheral surface of the roller with a certain tension. It is possible to prevent the release layer from peeling off without being able to follow the elongation in the surface direction or causing a crack when being wound and fixed while applying. Further, if the thickness of the base material layer is within the above range, the flattening sheet can be provided with an appropriate followability for winding around the outer peripheral surface of the roller and an appropriate stiffness for not easily bending. it can.

  The method for producing a color filter of the present invention includes a step of forming a transparent resin layer colored at least partially on a substrate, and a roller around which the flattened sheet according to any one of claims 1 to 3 is wound, And a step of flattening the surface by rolling the roller on the surface in a state where a contact surface constituted by the surface of the flattening sheet is in contact with the surface of the transparent resin layer. It is characterized by this.

  According to the present invention, in order to flatten the transparent resin layer, a roller having a contact surface wound around the flattened sheet of the present invention and brought into contact with the surface of the transparent resin layer formed on the substrate is used. Therefore, the entire transparent resin layer can be uniformly flattened without causing reverse transfer of the transparent ink forming the transparent resin layer or causing a defect in the transparent resin layer due to foreign matters. Therefore, it is possible to manufacture a color filter having a transparent resin layer having a smooth surface and free from the defects.

  According to the present invention, the entire transparent resin layer can be uniformly flattened, and the transparent ink forming the transparent resin layer can be prevented from being reversely transferred, and a defect in the transparent resin layer due to contamination by foreign matters can be prevented. Can be provided. Moreover, according to this invention, the manufacturing method of the color filter using the said planarization sheet can be provided.

The planarization sheet of the present invention is used for producing a color filter by planarizing the surface by rolling on the surface of a transparent resin layer formed on a substrate and colored at least partially. It is wound around the outer peripheral surface of the roller to form a contact surface of the roller that directly contacts the surface of the transparent resin layer, from the outer surface constituting the contact surface to the outer peripheral surface of the roller The release layer, the base material layer, and the elastic layer are integrally formed in order toward the inner side surface that comes into contact therewith.

Of the above layers, the release layer is a layer for forming the contact surface of the roller, and the surface tension (23 ° C.) of the release layer serving as the contact surface must be 30 mN / m or less. is there. When the surface tension exceeds the above range, the release layer has a releasability from the transparent resin layer, and the transparent ink that forms the transparent resin layer at the time of flattening is the release layer . Reverse transfer to the surface causes a problem that a defect such as a concave portion is generated in the transparent resin layer or the transparent resin layer is destroyed.

In addition, while securing the adhesiveness of the release layer to the base material layer, the release layer is prevented from being lost at an early stage by peeling, and the life of the flattening sheet is extended, In consideration of more reliably preventing the occurrence of reverse transfer of the transparent resin layer, the surface tension (23 ° C.) of the release layer is 5 to 25 mN / m, particularly 10 to 20 mN / m even within the above range. Is preferred.
The surface tension γ _S (23 ° C.) of the release layer is expressed by a value obtained by the Owens and Wendt method as an extension of the Fowkes theory. That is, in a measurement environment at a temperature of 23 ° C., a surface tension γ _L , a dispersion component γ _L ^{d of the} surface tension, and a polar component γ _L ^p are known on the surface of the release layer as a measurement target. A droplet was dropped and measured using a fully automatic contact angle meter DM700 manufactured by Kyowa Interface Science Co., Ltd., the contact angle θ (°) of the solvent, the surface tension γ _L , the dispersion component γ _L ^d , And the polar component γ _L ^p , the formula (1):
γ _L (1 + Cos θ) = 2 (γ _S ^d γ _L ^d ) ^1/2 +2 (γ _S ^p γ _L ^p ) ^1/2 (1)
To determine the dispersion component γ _S ^d and the polar component γ _S ^p of the surface tension γ _{S on} the surface of the release layer, and from the dispersion component γ _S ^d and the polar component γ _S ^p , 2):
γ _S = γ _S ^d + γ _S ^p (2)
To obtain the surface tension γ _S (23 ° C.) of the release layer.

  The release layer can be formed of various materials that can form a layer that satisfies the range of the surface tension. Particularly, the release layer is formed of a resin having a small surface energy, such as a silicone resin or a fluororesin. It is preferable for improving the durability of the release layer and extending the life of the flattened sheet. The release layer is coated with a coating solution containing the resin or its precursor on one side and then dried, or when the precursor is contained, the precursor is reacted to produce a resin. It can be formed by a so-called coating method.

In addition, the release layer is stipulated in Japanese Industrial Standard JIS B0601: 2001 “Product Geometric Characteristic Specification (GPS) —Surface Properties: Contour Curve Method—Terminology, Definitions, and Surface Property Parameters” of the surface to be the contact surface of the roller been, arithmetic mean roughness R _a of a roughness curve is required to be 20nm or less. If the arithmetic mean roughness R _a exceeds the above range, since the smoothness of the surface of the release layer is lowered, the surface of the transparent resin layer is planarized by pressing the said surface, the surface shape of the release layer Is transferred, thereby causing unevenness in the thickness of the transparent resin layer. For this reason, when the color filter having the transparent resin layer is incorporated in, for example, an LCD or the like, there is a problem in that unevenness in density occurs in the display according to the unevenness in the thickness of the transparent resin layer, resulting in a reduction in image quality. Arise.

Incidentally, as small as possible unevenness of thickness of the transparent resin layer, the display quality, such as LCD, considering that further improved, the arithmetic mean roughness R _a of the surface of the release layer, 15 nm even in the above range Hereinafter, it is particularly preferably 10 nm or less. In consideration of further improving the effect, the arithmetic average roughness _Ra is preferably as small as possible, and the lower limit may include up to 0 nm.

However, the arithmetic mean roughness R _a of the surface of the release layer formed by the coating method, the subject of the substrate layer is a base, the influence of the surface state of the surface to form a releasing layer, the base layer In consideration of the fact that it is substantially difficult to finish the surface on which the release layer is formed into _a smooth surface having no roughness, the arithmetic mean roughness Ra of the roughness curve is 0 nm. arithmetic mean roughness R _a of the surface of, 3 nm or more even in the above range, and particularly preferably between 5nm or more.

The arithmetic mean roughness R _a of the surface of the release layer formed by a coating method, in order to adjust the range, as described above, the surface state of the surface of the release layer, the substrate layer is a base Therefore, it is important to finish the surface of the base material layer as smoothly as possible because it is affected by the surface state of the surface on which the release layer is formed. Further, when the release layer is formed by a coating method, for example, a coating film whose surface is as smooth as possible is formed, such as a bar coating method using a coating rod whose outer peripheral surface is polished and a spray coating method. It is also important to adopt a coating method that can be applied and, if necessary, to polish and finish the surface of the release layer after formation. Arithmetic mean roughness R _a of the surface of the release layer, using a color 3D laser microscope [KEYENCE manufactured VK-9700], from the results obtained by measuring non-contact 3D, previously described JIS It shall be expressed by a value calculated according to the standard.

  The thickness of the release layer is preferably 30 μm or less, particularly preferably 15 μm or less. When the thickness exceeds the above range, the entire flattening sheet becomes soft and uniform pressure cannot be applied to the transparent resin layer at the time of flattening. Can not be converted. Further, during the planarization, the release layer moves in the shearing direction, so that the smoothness of the surface is lowered, and the thickness of the transparent resin layer is uneven. There is a possibility that the transparent ink to be formed is reversely transferred to the surface of the release layer.

  Note that the thickness of the release layer is preferably 0.5 μm or more, particularly 1 μm or more, even within the above range. This is because when the thickness is less than the above range, the effect of preventing reverse transfer of the transparent ink forming the transparent resin layer due to the provision of the release layer may not be sufficiently obtained. The thickness of the release layer is a state in which a part of the release layer is melted and peeled off using acetone, and a step is formed between the part that is not peeled off, The color 3D laser microscope described above (VK-9700 manufactured by Keyence Co., Ltd.) is used to represent the values obtained by non-contact three-dimensional measurement.

  The base material layer supports the upper and lower release layers and the elastic layer to mainly improve the tensile strength in the surface direction of the entire flattened sheet, and to the flattened sheet on the outer peripheral surface of the roller. It is a layer for imparting an appropriate followability for winding and an appropriate stiffness for preventing bending easily, and the tensile elastic modulus (23 ° C.) of the base material layer is 100 MPa or more, particularly 200 MPa or more. Preferably there is.

If the tensile modulus (23 ° C.) is less than the above range, the flattened sheet has insufficient tensile strength in the surface direction, and the flattened sheet is wound around the outer peripheral surface of the roller and fixed with a constant tension. When doing so, the release layer may not be able to follow the elongation in the surface direction and may peel off or cause cracks. The upper limit of the tensile elastic modulus (23 ° C.) is not particularly limited, but the tensile elastic modulus (23 ° C.) of the base material layer is set to maintain an appropriate followability for winding around the outer peripheral surface of the roller. Even within the above range, it is preferably 10 GPa or less, particularly 5 GPa or less. The tensile elastic modulus of the base material layer is expressed as a value measured in accordance with Japanese Industrial Standard JIS K6251: 2004 “Vulcanized rubber and thermoplastic rubber-Determination of tensile properties” in a measurement environment at a temperature of 23 ° C. To do.

  The base material layer can be formed of various materials that can form a layer satisfying the range of the tensile elastic modulus (23 ° C.). As the base material layer, in particular, polyethylene terephthalate (PET) or the like can be used. A so-called engineering plastic film such as a polyester resin film, a polyamide resin film such as nylon, or a wholly aromatic polyimide resin film such as Kapton (registered trademark) is preferably used. Further, as the base material layer, a metal foil or thin plate of aluminum, nickel, stainless steel, iron, copper or the like can be used.

  The thickness of the base material layer is preferably 50 to 500 μm, particularly preferably 75 to 350 μm. If the thickness is less than the above range, the flattening sheet cannot be imparted with an appropriate stiffness to prevent bending, and if it exceeds the above range, the flattening sheet is wound around the outer peripheral surface of the roller. In any of these cases, the flatness sheet is wound around the outer peripheral surface of the roller while being fixed with a certain tension, and the handleability is lowered. There is a fear. The thickness of the base material layer is expressed by a value measured using a micrometer (for example, a waterproof digital micrometer “Coolant Proof Micrometer” manufactured by Mitutoyo Corporation).

Specified in Japanese Industrial Standard JIS B0601: 2001 “Product Geometrical Specification (GPS) —Surface Properties: Contour Curve Method—Terminology, Definitions, and Surface Property Parameters” of the surface of the release layer side of the base material layer, arithmetic mean roughness R _a of a roughness curve is required to be 50nm or less. If the arithmetic mean roughness R _a exceeds the above range, on the surface, the release layer formed by a coating method, an arithmetic mean roughness R _a of the surface comprising the contact surface of the roller, described above Since it exceeds the range of 20 nm or less, there arises a problem that the image quality of an LCD or the like is lowered.

Incidentally, the arithmetic mean roughness R _a of the surface of the release layer, considering that within the preferred range described above, the base layer, the arithmetic average roughness of the surface of the release layer side R _a is Even within the above range, it is preferably 15 nm or less, particularly 10 nm or less. Further, the arithmetic mean roughness R _a of the surface of the release layer, considering that as small as possible, the base layer, the arithmetic average roughness R _a of the surface of the release layer side, the smaller Preferably, The lower limit may include up to 0 nm.

However, as described above, the substrate layer, a surface forming a release layer, the arithmetic average roughness R _a of 0nm of the roughness curve, to finish the no irregularities smooth surface, the substrate layer In view of the productivity and the like, it is substantially difficult, and in consideration of the productivity and the like, the arithmetic average roughness _Ra is preferably 3 nm or more, particularly 5 nm or more even within the above range. Of the base layer, the arithmetic average roughness R _a of the surface forming the release layer, in order to adjust within the range, for example, if the base layer is a foil or thin sheet like metals, The surface may be polished to a smooth finish. In addition, when the base material layer is a so-called engineering plastic film, for example, the conditions in each step of manufacturing the film, such as extrusion molding or stretching, are adjusted, or the surface of the manufactured film is polished. Then, it may be finished smoothly. Of the base layer, the arithmetic average roughness R _a of the surface forming a release layer, by using a color 3D laser microscope as described previously [KEYENCE manufactured VK-9700], measured non-contact 3D From the results obtained in this way, it is expressed by a value calculated according to the JIS standard described above.

  The elastic layer, as a cushion layer, applied uniform pressure to the transparent resin layer during flattening, and when the flattened sheet was wrapped around and fixed to the outer peripheral surface of the roller, foreign matter was sandwiched between them. In this case, the shape of the foreign matter is absorbed and the surface of the flattening sheet is suppressed from appearing as a protrusion, and a defect such as a recess corresponding to the protrusion is generated in the transparent resin layer to be flattened. The elastic modulus (23 ° C.) needs to be within a range of 0.5 to 20 MPa and a thickness of 0.1 to 5 mm.

  If the elastic modulus (23 ° C.) of the elastic layer is less than the above range, or if the thickness exceeds the above range, the entire flattening sheet becomes too soft, and the flattening resin layer becomes Since the uniform pressure cannot be applied, the transparent resin layer cannot be flattened uniformly. On the other hand, when the elastic modulus (23 ° C.) exceeds the above range or the thickness is less than the above range, when a foreign object is caught between the two when the flattened sheet is wound around and fixed to the outer peripheral surface of the roller. In addition, the shape of the foreign matter cannot be sufficiently absorbed, and the shape of the foreign matter is manifested as a protrusion on the surface of the flattening sheet, and the flattened transparent resin layer has a recess or the like corresponding to the protrusion. Defects occur.

  It should be noted that appropriate flexibility is imparted to the entire flattening sheet, and when the flattening, uniform pressure is applied to the transparent resin layer, and when the foreign matter is caught, the shape of the foreign matter is sufficiently Taking into account the balance between absorbing and suppressing the appearance of protrusions on the surface of the flattened sheet, considering forming a transparent resin layer that is flat and uniformly free of defects, The elastic modulus (23 ° C.) of the elastic layer is preferably 0.8 to 15 MPa and the thickness is preferably 0.125 to 0.35 mm even within the range described above.

  The elastic layer can be formed of various materials that satisfy the above characteristics, and is particularly preferably formed of foamed or non-foamed rubber or soft resin. The elastic modulus of the elastic layer is a value measured in accordance with the Japanese Industrial Standard JIS K6251: 2004 “Vulcanized rubber and thermoplastic rubber-Determination of tensile properties” described above in a measurement environment at a temperature of 23 ° C. Let's represent. The thickness is expressed by a value measured using a micrometer (for example, a waterproof digital micrometer “Coolant Proof Micrometer” manufactured by Mitutoyo Co., Ltd.) described above.

The planarizing sheet of the present invention may be formed of only three layers of the release layer, the base material layer, and the elastic layer, but an adhesive layer or the like may be interposed between the layers. In addition, each of the release layer, the base material layer, and the elastic layer may be formed in a laminated structure including two or more layers that satisfy the above-described characteristics. The flattened sheet consisting of only the three layers, for example, after applying the coating liquid that becomes the release layer on one surface of the base material layer, the release layer is dried or reacted as described above. Applying and drying a liquid or paste-like paste that dissolves rubber or soft resin in a solvent, which is the base of the elastic layer, on the opposite surface of the base material layer , and further if necessary It is manufactured by forming a resilient layer through a curing reaction.

  1 and 2 are cross-sectional views showing an example of steps in the method for producing a color filter of the present invention using the flattened sheet of the present invention. Referring to FIG. 1, in the manufacturing method of this example, first, the respective colors corresponding to the red (R), green (G), and blue (B) pixels are formed on a substrate 1 such as a glass substrate. Stripe patterns 2 to 4 made of colored transparent ink are regularly arranged and printed for each pixel to form the transparent resin layer 5. Next, referring to FIG. 2, the contact surface of the roller 7, which is the surface of the flattening sheet 6, of the roller 7 in which the flattening sheet 6 of the present invention is wound around the outer circumferential surface is printed on the transparent resin layer 5 The surface of the transparent resin layer 5 is rolled by rolling the roller 7 on the surface of the transparent resin layer 5 as indicated by solid arrows and white arrows in the figure. Is flattened, a color filter is manufactured.

  In the process of FIG. 1, as printing methods for printing the stripe patterns 2 to 4 on the substrate 1, various conventionally known printing methods such as an intaglio offset printing method, a lithographic offset printing method, and a screen printing method are used. However, both can be employed, and intaglio offset printing is particularly preferably employed. In the intaglio offset printing method, an intaglio offset printing machine including an intaglio having a recess corresponding to the shape of the stripe pattern and a roller having an offset blanket wound around the outer peripheral surface thereof is used.

  Then, after filling the concave portions of the intaglio with the transparent ink colored in each color, the roller is the surface of the offset blanket, the roller contact surface is in contact with the surface of the intaglio, The transparent ink in the recesses is transferred as a stripe pattern to the surface of the offset blanket by rolling on the surface, and then the roller is placed in the state where the surface is in contact with the surface of the substrate. When the stripe pattern is transferred onto the surface of the substrate by rolling on the surface of the substrate, a stripe pattern corresponding to the concave portion of the intaglio can be printed on the surface of the substrate.

  According to the intaglio offset printing method, a stripe pattern made of transparent ink corresponding to a high-precision pattern formed on the surface of the intaglio plate, for example, by a photolithographic method can be printed on the surface of the substrate with good reproducibility. There are advantages. In order to flatten the transparent resin layer after printing using the intaglio offset printing press and the flattening sheet of the present invention, in addition to the roller around which the offset blanket is wound, the flattening is performed. A roller around which a sheet is wound may be mounted, and the printing process using the former roller and the flattening process using the latter roller may be alternately performed. Further, the number of rollers may be only one, and the flattening step may be performed by winding the flattening sheet of the present invention around the roller after the printing step instead of the offset blanket.

Example 1
As a base layer, the both sides, an arithmetic mean roughness R _a of a roughness curve is 11.5 nm, the tensile modulus (23 ° C.) is 210 MPa, PET film thickness of 100μm [Toray Co., Ltd. T60] Prepared. Next, the PET film is cut into a rectangular shape having a length of 300 mm and a width of 400 mm, a mending tape is attached to each of the two long side edges of the rectangle, and the PET film is Bar coating method using a coating rod made of stainless steel having a diameter of 12 mm and having an outer peripheral surface polished, using the above-mentioned mending tape as a thickness guide while being fixed on a flat plate According to the above, on one side, a silicone resin-based coating liquid [registered trademark SEPA-COAT manufactured by Shin-Etsu Chemical Co., Ltd., surface tension of single cured product (23 ° C.): 16 mN / m] After coating, the coating liquid was dried in a clean oven at 100 ° C. for 10 minutes and the silicone resin was cured to form a release layer. Of the releasing layer, the surface tension of the surface (23 ° C.) is 16 mN / m, an arithmetic mean roughness R _a of a roughness curve is 8.7 nm, the thickness was 1 [mu] m.

  Next, the PET film was placed on a flat plate with the surface opposite to the side on which the release layer was formed facing up, and stainless steel bars were placed on the edges of the four sides of the rectangle, respectively, and the height was 500 μm. In addition to forming a bank, and using a stainless steel rod having a thickness of 12 mm and a polished outer peripheral surface, the stainless steel rod is used as a thickness guide while the PET film is fixed on a flat plate. Then, by the bar coating method, the casting urethane resin [KU-5550-9 manufactured by Hitachi Chemical Co., Ltd., the elastic modulus of the single cured product (23 ° C.): 5.3 MPa] was applied, followed by heating at 40 ° C. for 5 minutes in a clean oven to cure the urethane resin to form an elastic layer, and the flattened sheet of Example 1 was manufactured. The elastic layer had an elastic modulus (23 ° C.) of 5.3 MPa and a thickness of 0.65 mm.

Example 2
As a silicone resin-based coating solution for the release layer, Shin-Etsu Chemical Co., Ltd. registered trademark SEPA-COAT and KS-830 manufactured by the same company (surface tension of single cured product (23 ° C.): 38 mN / M) was used in the same manner as in Example 1 except that a blending ratio of 40:60 by weight ratio was used, and a planarized sheet of Example 2 was produced. Of the releasing layer, the surface tension of the surface (23 ° C.) is 28 mN / m, an arithmetic mean roughness R _a of a roughness curve is 8.7 nm, the thickness was 1 [mu] m.

<< Comparative Example 1 >>
As a silicone resin-based coating solution for the release layer, the registered trademark SEPA-COAT manufactured by Shin-Etsu Chemical Co., Ltd. and KS-830 manufactured by the same company are blended in a weight ratio of 20:80. A flattened sheet of Comparative Example 1 was produced in the same manner as in Example 1 except that the above was used. Of the releasing layer, the surface tension of the surface (23 ° C.) is 32 mN / m, an arithmetic mean roughness R _a of a roughness curve is 8.7 nm, the thickness was 1 [mu] m.

<< Comparative Example 2 >>
A flattened sheet of Comparative Example 2 was produced in the same manner as in Example 1 except that KS-830 manufactured by Shin-Etsu Chemical Co., Ltd. was used as the silicone resin-based coating solution for the release layer. did. Of the releasing layer, the surface tension of the surface (23 ° C.) is 38 mN / m, an arithmetic mean roughness R _a of a roughness curve is 10.5 nm, the thickness was 1 [mu] m.

Example 3
As a silicone resin-based coating solution for the release layer, the registered trademark SEPA-COAT manufactured by Shin-Etsu Chemical Co., Ltd. and KS-837 manufactured by the same company (surface tension (23 ° C.) of single cured product: 16 mN) / M) was used in the same manner as in Example 1 except that a blending ratio of 80:20 by weight was used, and a planarized sheet of Example 3 was produced. Of the releasing layer, the surface tension of the surface (23 ° C.) is 16 mN / m, an arithmetic mean roughness R _a of a roughness curve is 18 nm, the thickness was 1 [mu] m.

<< Comparative Example 3 >>
As a base layer, the both sides, an arithmetic mean roughness R _a of a roughness curve is 66.8Nm, tensile modulus (23 ° C.) is 230 MPa, a thickness of 100 [mu] m PET film [Teijin DuPont Films Co. Ltd. A flattened sheet of Comparative Example 3 was produced in the same manner as in Example 1 except that the registered trademark Melinex S] was used. The PET film on the surface of the formed release layer, the arithmetic average roughness R _a of a roughness curve was 39 nm.

Example 4
Use as a base layer, the both sides, an arithmetic mean roughness R _a is 48nm of the roughness curve, the tensile modulus (23 ° C.) is 230 MPa, a PET film [Toray Industries (Inc.) S10 manufactured] a thickness of 100μm A flattened sheet of Example 4 was produced in the same manner as Example 1 except that it was. The PET film on the surface of the formed release layer, the arithmetic average roughness R _a of a roughness curve was 8.7 nm.

<< Comparative Example 4 >>
Use as a base layer, the both sides, an arithmetic mean roughness R _a is 52nm of the roughness curve, the tensile modulus (23 ° C.) is 230 MPa, a PET film [Toray Industries (Inc.) S15 manufactured] a thickness of 100μm A flattened sheet of Comparative Example 4 was produced in the same manner as Example 1 except that it was. The PET film on the surface of the formed release layer, the arithmetic average roughness R _a of a roughness curve was 8.7 nm.

Example 5
As the urethane resin for casting used as the basis of the elastic layer, KU-7002 manufactured by Hitachi Chemical Co., Ltd. (modulus of single cured product (23 ° C.): 0.07 MPa) and KU-7008 manufactured by the same company ( The flattening of Example 5 was carried out in the same manner as in Example 1 except that a mixture of the elastic modulus of the single cured product (23 ° C .: 0.95 MPa) and a weight ratio of 50:50 was used. A sheet was produced. The elastic modulus (23 ° C.) of the elastic layer was 0.55 MPa.

<< Comparative Example 5 >>
As the urethane resin for casting, which is the basis of the elastic layer, KU-7002 made by Hitachi Chemical Co., Ltd. and KU-7008 made by the same company are blended at a weight ratio of 40:60. A flattened sheet of Comparative Example 5 was produced in the same manner as Example 1 except that it was. The elastic modulus (23 ° C.) of the elastic layer was 0.45 MPa.

<< Comparative Example 6 >>
A flattened sheet of Comparative Example 6 was produced in the same manner as in Example 1 except that KU-7002 manufactured by Hitachi Chemical Co., Ltd. was used as the urethane resin for casting used as the basis of the elastic layer. The elastic modulus (23 ° C.) of the elastic layer was 0.07 MPa.
Example 6
As the urethane resin for casting which becomes the basis of the elastic layer, KU-5550-9 manufactured by Hitachi Chemical Co., Ltd. and U-801A / B manufactured by the same company (elastic modulus (23 ° C.) of single cured product: 32 MPa) ) Was used in the same manner as in Example 1 except that a blending ratio of 55:45 by weight ratio was used, and a planarized sheet of Example 6 was produced. The elastic modulus (23 ° C.) of the elastic layer was 18 MPa.

<< Comparative Example 7 >>
Mixing KU-5550-9 manufactured by Hitachi Chemical Co., Ltd. and U-801A / B manufactured by Hitachi Chemical Co., Ltd. at a weight ratio of 45:55 A flattened sheet of Comparative Example 7 was produced in the same manner as in Example 1 except that the above was used. The elastic modulus (23 ° C.) of the elastic layer was 22 MPa.

<< Comparative Example 8 >>
Except that the elastic layer was formed using a silicone resin [SCR-1011A / B manufactured by Shin-Etsu Chemical Co., Ltd., elastic modulus of single cured product (23 ° C.): 1400 MPa], the same as in Example 1, A planarized sheet of Comparative Example 8 was produced. The elastic modulus (23 ° C.) of the elastic layer was 1400 MPa.

<< Examples 7 and 8, Comparative Examples 9 to 11 >>
The thickness of the elastic layer is 0.11 mm (Example 7), 4.8 mm (Example 8), 0.08 mm (Comparative Example 9), 5.2 mm (Comparative Example 10), and 6.5 mm (Comparative Example 11). Except that, flattened sheets of Examples 7 and 8 and Comparative Examples 9 to 11 were produced in the same manner as Example 1.
<< Comparative Example 12 >>
A planarized sheet of Comparative Example 12 was produced in the same manner as in Example 1 except that no elastic layer was formed.

"Evaluation test"
Using a flat intaglio offset printing machine (manufactured by Nakan Co., Ltd.) on the surface of a glass substrate having a length of 300 mm and a width of 400 mm, an intaglio offset printing method and a CF ink for intaglio offset with a line width of 100 μm and three colors RGB The stripe pattern was printed with a 100 μm pitch arranged in order as shown in FIG. 1 to form a transparent print layer. The intaglio plate is made of glass and has an opening width of 110 μm and a depth of 7 μm corresponding to the shape of the stripe pattern. The offset blanket is made of SRI R & D Co., Ltd. with a total thickness of 0. A 9 mm precision printing silicone blanket was used.

  Also, as CF ink for intaglio offset, melamine (registered trademark Sumimar manufactured by Sumitomo Chemical Co., Ltd.) is added to a polyester resin synthesized by blending equal amounts of adipic acid and phthalic acid at 180 ° C. In addition, a binder resin whose weight average molecular weight Mw is arbitrarily adjusted within the range of 2000 to 20000 while being heated to 200 ° C., one of the following pigments, and a dispersant [registered trademark Ajisper manufactured by Ajinomoto Co., Inc. PB821] and butyl carbitol acetate as a solvent were blended in the proportions shown in Table 1 and mixed using three rolls.

(Pigment)
Red: C.I. I. Pigment Red 245 (diketopyrrolopyrrole pigment)
Green: C.I. I. Pigment Green 36 (copper halide phthalocyanine pigment)
Blue: C.I. I. Pigment Blue 15: 6 (copper phthalocyanine pigment)

  Next, the offset blanket was removed from the roller of the printing press, and instead, the flattened sheets produced in Examples and Comparative Examples were wound and fixed. After the surface of the flattening sheet is flattened by rolling the roller on the surface in a state where the contact surface of the roller is in contact with the surface of the transparent resin layer The color filter was manufactured by heating at 230 ° C. for 30 minutes to cure the transparent resin layer.

The surface of the flattened sheet after flattening was observed to confirm whether reverse ink transfer occurred. Moreover, the surface of the transparent resin layer after hardening was observed with a microscope, and the surface unevenness before and after planarization was evaluated as poor planarization. As for those flattened, the surface arithmetic mean roughness R _a of a roughness curve, stepped, surface roughness, fine shape measuring apparatus [KLA-Tencor Co. Alpha Step 500] using measured Te, those exceeding the arithmetic average roughness R _a is 20 nm, there irregularity of thickness in the transparent resin layer, the following ones without unevenness 20 nm, was evaluated as smoothness good. Furthermore, the surface of the transparent resin layer was observed with a microscope, and it was confirmed whether or not defects such as recesses were generated in the transparent resin layer. The results are shown in Tables 2 to 7.

From each table, when using the flattened sheet of Comparative Examples 1 and 2 in which the surface tension (23 ° C.) of the surface of the release layer exceeded 30 mN / m, reverse transfer of ink occurred. understood. Further, as the substrate layer, since the arithmetic mean roughness R _a of the surface was used in excess of 50 nm, Comparative Example 3 in which the arithmetic mean roughness R _a of the surface of the release layer exceeds 20nm flattened sheet when used, since the arithmetic mean roughness R _a of the surface of the transparent resin layer exceeds 20 nm, it was found that cause uneven thickness of the transparent resin layer. Although the arithmetical mean roughness R _a of the surface of the release layer was 20nm or less, as a base layer, planarization of Comparative Example 4 an arithmetic mean roughness R _a of the surface was used in excess of 50nm in the case of using the sheet, also since the arithmetic mean roughness R _a of the surface of the transparent resin layer exceeds 20 nm, it was found that cause uneven thickness of the transparent resin layer.

  Further, the flattened sheets of Comparative Examples 5 and 6 in which the elastic modulus (23 ° C.) of the elastic layer was less than 0.5 MPa, and the flattened sheets of Comparative Examples 10 and 11 in which the thickness of the elastic layer exceeded 5 mm were used. It was found that the transparent resin layer could not be flattened. Further, the flattened sheets of Comparative Examples 7 and 8 in which the elastic modulus (23 ° C.) of the elastic layer exceeded 20 MPa, the flattened sheet of Comparative Example 12 in which no elastic layer was formed, and the thickness of the elastic layer was 0.1 mm. It was found that when the flattened sheet of Comparative Example 9, which was less than the above, was used, it was not possible to prevent the occurrence of defects such as recesses in the transparent resin layer. On the other hand, when the flattened sheets of Examples 1 to 8 are used, the entire transparent resin layer can be uniformly flattened and the transparent ink forming the transparent resin layer is reversely transferred. It has been confirmed that defects such as recesses can be prevented from occurring in the transparent resin layer.

It is sectional drawing which shows an example of the process of the manufacturing method of the color filter of this invention using the planarization sheet | seat of this invention. FIG. 2 is a cross-sectional view showing an example of a continuation process of FIG. 1.

Explanation of symbols

1 Substrate 2, 3, 4 Stripe pattern 5 Transparent resin layer 6 Flattening sheet 7 Roller

Claims (4)

By rolling on the surface of the transparent resin layer formed on the substrate and colored at least partly, the surface is flattened and wound around the outer peripheral surface of a roller used for manufacturing a color filter. In the flattening step, a flattened sheet constituting the contact surface of the roller that directly contacts the surface of the transparent resin layer, the inner surface contacting the outer peripheral surface of the roller from the outer surface constituting the contact surface The release layer, the base material layer, and the elastic layer are integrally formed in order, and the surface tension (23 ° C.) of the surface of the release layer serving as the contact surface is 30 mN / m or less, and The arithmetic mean roughness Ra of the roughness curve is 20 nm or less, the arithmetic mean roughness Ra of the roughness curve of the surface of the base layer of the release layer is 50 nm or less, and the elastic modulus of the elastic layer ( 23 ° C.) is 0.5-20 MPa and the thickness is 0.1 Flattening sheet being in the range of 5 mm.   The planarization sheet according to claim 1, wherein the release layer has a thickness of 30 μm or less. The planarized sheet according to claim 1 or 2 , wherein the base material layer has a tensile elastic modulus (23 ° C) of 100 MPa or more and a thickness of 50 to 500 µm. On a substrate, constituted by at least partially forming a transparent resin layer which is colored, of claims 1 to roller wrapped with flattened sheet according to any one of 3, the surface of the flattening sheets And a step of flattening the surface by rolling the roller on the surface in a state where the contact surface is in contact with the surface of the transparent resin layer. Production method.

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