TWI298340B - Manufacturing method of an optical film - Google Patents

Description

1298340 IX. Description of the Invention: [Technical Field] The present invention relates to an optical film and a mixed optical polymer for the preparation of the above optical film, in particular to a PMMA (Polymethyl Methacrylate) optical film and a solvent casting film technique A method of preparing the above PMMA optical film. [Prior Art]

The substrate of the conventional optical film is generally based on triacetate (TAC: triacetate), PC (polycarbonate), and COP. The typical TAC film can be further used as a protective and supporting film for the optical film. Therefore, in addition to the required optical properties, the general TAC film must have a certain strength and have high temperature resistance and moisture resistance to achieve optical. The use of the film is required to provide an effect of protecting the optical film composed of the TAC film (refer to the following patents: JP4342202, TW499573, JP2000-324055, JP2001-235625, JP2003-195048, EP 1-285742, EP 1-331245). In addition, U.S. Patent No. 6,652,926 B1 discloses the addition of 0.04% to 0.3% of silica particles in TAC, which increases the toughness of the TAC film on the one hand and decreases the film thickness of TAC on the other hand. Further, the production of a substrate or a protective film is disclosed in U.S. Patent Publication No. 2004/0086721 A1, which discloses a PVDF (polyvinylidene fluoride) of 20 to 40% and a PMMA of 40 to 60%. (Polymethyl Methacrylate) and 5 to 18% of acrylic elastomer (polypropylene elastomer) are melt-blended to form a substrate or a protective film. European Patent No. 1298340 EPl 154005 A1 discloses a PET film having a fineness of less than 5 micrometers (um) in a PET film to achieve a center thickness of 20 to 600 nanometers (nm). In addition, Japanese Patent Laid-Open No. Hei 7-56017 mentions that a film of 80% (um) is molded by PC80%+PMMA (Kuraray C-16) 20%, and 75% of PMMA (MMA97%+BA3%) material is mixed. A 500 micron (um) film cast with 25% PEA.

Disadvantages of the above-mentioned prior art include: the TAC film has a large water absorption and moisture permeability. Therefore, when used under high temperature and high humidity conditions, the optical properties of the optical film are affected due to deformation or stress generated by the external environment. 'Also caused the optical film to be unusable. And the value of b of TAC is too high, it can be seen in appearance, it is easy to cause visual obstacles. In addition, COP films (e.g., Zeonor, Arton) have too little water absorption and moisture permeability, poor adhesion properties, and have a problem that the materials are too brittle. Although the fine particles in the European Patent No. EP1154005A1 can reduce the surface roughness, the glass transition temperature of the pET used is low (75. 〇, which cannot meet the heat resistance requirements of the existing optical film. Japanese Patent Laid-Open No. 7_56〇17 The material of the PMMA/PC blended material is too brittle, and the PMMA/PEA blended material has a thickness of up to 500 micrometers (um). Compared with the existing optical film, the applicability is insufficient in view of the above disadvantages, and in order to avoid melting The invention is capable of solving the above-mentioned shortcomings by improving the heat resistance, moisture resistance and mechanical properties of the optical film by melt blending or thermoplastic processing, and effectively solving the problem of stability of the optical film. The invention relates to an optical film using a solvent cast film technology and a manufacturing method thereof, and the PMMA is soluble in a solvent such as toluene which does not have a shoulder 1298340, which can be avoided. A further use of dichloromethane in the TAC process may cause harm to the human body and the environment. A further object of the present invention is to provide a moderate suction Water and moisture permeability can effectively solve the problem of optical properties of optical films.

Still another object of the present invention is to provide a heat resistance, moderate mechanical properties, low photoelastic coefficient, and good optical properties such as low haze, low yellowing index, high Abbe number, and visible light range (wavelength 4 〇). 〇~700 nm) optical film with high penetration (>90%) and uniform film properties (such as thickness, surface roughness, etc.), and materials due to melt blending or thermoplastic processing Unstable phenomenon. The optical film disclosed in the present invention comprises: at least one PMMA, a PMMA or a PMMA blended with a substituted functional group; and a solvent, the PMMA, the PMMA or the PMMA blended with the substituted functional group can be uniformly distributed in an arbitrary ratio according to a desired property. The mixture is mixed in the above solvent to form a mixed solution comprising 20 to 40% by weight of PMMA after heat treatment to form an optical film. The above functional group is a fluorenyl group, and the PMMA of the above substituted functional group includes ethyl, propyl, isopropyl, n-butyl, isobutyl, neobutyl, n-hexyl, isohexyl, cyclohexyl, etc. The functional group replaces the PMMA of the thiol group. The above blending includes at least one polymer, small molecule, plasticizer, UV absorber, antidegradant or nanoparticle blending. The above solvent includes at least one aromatic, naphthenic, etheric, ester or ketone. The above aromatics include toluene, o-, m- or p-nonylene (Xylene), cycloalkanes include cyclohexane, and ethers include diethyl ether (Diehtyl Ether) and tetrahydrofuran (Tetrahydrofuran · 7

1298340 THF ), g is intended to include Methyl acetate, Ethyl acetate, and ketones include acetone (Acetone), methylethylketone (MEK), 1-methylpyrrolidone (l-methylpyrrolidone: NMP). The thickness of the above optical film is between 20 and 200 micrometers (μm); and the optical film can be applied to an optical film substrate or an optical film protective film of an LCD, an LED, an OLED or a PLED. The method for fabricating an optical film according to the present invention comprises: mixing at least one PMMA, a substituted functional group of PMMA or PMMA with a solvent to form a uniform mixed solution; and uniformly distributing the mixed solution on a substrate. And, a heat treatment is performed to obtain an optical film having a uniform surface. The mixed solution is uniformly distributed on the substrate by a solvent cast film. The above solvent casting method includes blade coating, wire bar coating, reverse or co-roll coating, air curtain coating, wheel coating, engraving coating, dip coating , spin coating, slit coating, extrusion coating or curtain coating. The substrate includes a glass substrate, a plastic substrate, a mirror steel plate, a mirror steel strip, or a synthetic polymer having a good surface uniformity. The above synthetic polymer PET (polyethylene terephthalate), PEN (polyethylene naphthalate), PES (polyethersulfone), Pl (polyimide), PAR (polyarylate), PC (polycarbonate), or natural fibers such as CA (cellulose acid), DAC (cellulose diacetate), TAC (cellulose triacetate) and the like. The mixed solution is uniformly distributed on the substrate to have a thickness of 150 μm to 1200 μm. The heat treatment is a mixed solution uniformly distributed on the substrate by UV light. The method for producing the optical film of the present invention further comprises coating a material such as a discotic liquid crystal on the optical film and exposing it via a roller or uv. The alignment is carried out in the same manner to obtain a phase difference optical film having a phase difference.

Further, in the optical film of the present invention, PMMA rubber particles formed by coating a rubber elastic material with PMMA and/or PMMA substituted with a functional group may be further added, wherein the rubber elastic material may be Select butyl acrylate and/or poly-α-chloro acrylate to PMMA Poly (methyl methacrylate) and/or styrene, and the rubber elastic material has a particle size smaller than 丨〇 The micron can even be further nanometer scale to enhance the mechanical properties of the optical film. [Embodiment] Herein, the present invention will be described in detail with some embodiments. However, it is to be understood that the invention may be embodied in a wide variety of other embodiments, and the scope of the invention is not limited to the embodiments described above. . The optical film disclosed in the present invention comprises: at least one pMMA, a PMMA or a PMMA blended with a substituted functional group; and the PMMA or PMMA blended with the above substituted PMMA' can be uniformly mixed in an arbitrary ratio according to a desired property. In the above solvent, the mixed solution is subjected to heat treatment to form a substrate of an optical film. Please refer to Fig. 1, which shows a flow chart of the optical film of the present invention. In the method for producing the optical film of the present invention, first, in step 101, a PMMA polymer and a solvent are selected, that is, one or two or more types of PMMA or a chemically/physically modified pMMA are selected, according to the number 9 1298340

The properties are required to be uniformly dissolved in the solvent in any ratio. For example, the above chemical methods include PMMA substituted with a functional group, for example, ethyl, propyl, isopropyl, n-butyl, isobutyl, neobutyl, n-hexyl, isohexyl, cyclohexyl The isofunctional group replaces the methyl group. For example, the above physical methods include PMMA blending, and the blending includes at least one polymer, small molecule, plasticizer, UV absorber, antidegradant or nanoparticle blending. In one embodiment, the above solvent comprises at least one of an aromatic, a cyclamate, an ether, an ester, a ketone, or a mixture thereof. For example, the above aromatics include toluene, o-, m- or p-xylene (Xylene), cyclohexanes include cyclohexane, ethers include diethyl ether (Diehtyl Ether), tetrahydrogen 11 Tetrahydrofuran (THF), esters include methyl acetate (Ethyl acetate), and ketones include acetone (Acetone), methyl ethylketone (MEK), 1-mercaptocyclopentanone (l -methylpyrrolidone: NMP). The above solvent selection is only an example and is not intended to limit the invention. The particle size of the above-mentioned nanoparticle particles is preferably not more than 100 nm, preferably less than 80 nm, preferably less than 50 nm. By way of an embodiment, the present invention proposes a four-part solvent cast film technique for preparing a formulation, composition and solvent of a PMMA optical film, as follows: 1. Degussa 8N 100 part, Toluene 200 part; 2 > Degussa 8N 97.5 part, Kuraray GR00100 2.5 part, Acetone 200part; 3, Degussa 8N 80part, Degussa zk5BR 2.5 part, Methyl acetate 200part; 1298340 4. Degussa 8N 50 part, Kuraray GR049402.5 part, Toluene200part. Next, in step 102, the selected PMMA polymer and the solvent are formed into a solution system by a solvent mixing technique and tested. Please refer to Figure 2 for the test results. In addition, Figure 3 shows that the various physical or chemical properties of the PMMA film after PMMA is added to a small amount of silica can be from 0.5% to 15%.

The aforementioned Kuraray GR series can select GR04940, GR04970, GR00100, GR01240, GR01270, GR1000H24, GR1000H42 and GR1000H60, and can also use Degussa's zk3BR, zk4BR, zk5BR, zk6BR, zk4HC, zk5HC, k6HC, zk5HT, zk6HT, zkHF, Substituting any of zk6HF, zk20, zk30, zk40, and zk50. Preferably, the solids content of PMMA in the solution is between 20 and 40%. Then, in step 103, the solution is uniformly distributed on a substrate by solvent casting. For example, the substrate includes, but is not limited to, a glass substrate, a plastic substrate, a mirror steel plate, a mirror steel strip, or a composite having a good surface uniformity. Synthesis T^^^^i: PET (polyethylene terephthalate), PEN (polyethyleneeenaphthalate), PES (polyethersulfone), Pl (polyimide), PAR (polyarylate), PC (polycarbonate), or natural fiber such as CA (cellulose acid), DAC (cellulose diacetate), TAC (cellulose triacetate) and the like. In the step i3, the present invention coats the mixed solution on the glass substrate by using a doctor blade. For example, the gap (Gap) of the knife includes, but is not limited to, 550 micrometers, 650 micrometers, and 400. Micron (μηι). In addition, the manner of the above solvent cast film includes, but is not limited to, entanglement π

1298340 Bar coating, reverse or co-roller coating, so ±.,,.. air curtain coating, wheel coating 'carving coating, dip coating-V ^ Γ -, 靛 transfer coating, slit coating, leaking cloth or ke- cloth; the method of learning film can be used. In the manner of the above-mentioned solvent cast film, in addition to various coating methods, it can also be formed by extrusion molding or injection molding of a mirror mold to form an optical film. The film containing the solvent formed after coating is called a wet film, and the thickness of the wet film can be determined depending on the needs. Preferably, the thickness of the wet film may be from 150 micrometers to 1200 micrometers ((4). Then step 1〇4' is performed in this step through the oven (four) segment or continuous temperature rise (for example: irradiation with UV light) The method of 'drying the film by the above method. In the preferred case, the drying to the stage where the residual amount of the solvent is not more than 1%' can form an optical film having good optical properties and a uniform film surface (relative to the wet film) The thickness of the optical enthalpy can be controlled by the proportion of the solvent and the heating time and temperature, and the dry film can be improved in the solution by surface chemical treatment. The purpose is to enhance the formation. The degree of heat resistance of the film does not affect the optical uniformity of the dry film. The present invention utilizes a one-stage heating method for drying, for example, heating the solvent in the formulation and composition of the above-mentioned enamel optical film to 9 (rc, and vigorously stirring Stir at this temperature for one hour, after the particles are completely dissolved, remove the heat source and maintain stirring to room temperature, then let stand for 35 um (um) gauze and let stand for a while. The mixture was poured onto a glass substrate, and the excess coating liquid was scraped off with a 550 μm gap. Then, it was placed in an oven for 10 minutes, heated to 80 ° C and maintained for 2 minutes. , warm up every 12 1298340 by 20 ° C and maintain 20 minutes, until 16 〇 it, and maintain for 30 minutes. Finally, heat to 18 〇〇 c and maintain for 2 hours. As a result, the obtained film The solvent residue is 01%, and the film thickness is 94 microns (called ^), and optical test and mechanical strength test are performed. Among them, the optical test can be penetration, Haze, b value, etc., and the mechanical strength can be the elongation rate (%) ), tensile strength (MPa), tensile modulus (1^1^), etc. Further, the above pMMA film may be extended by heating, coated with a disk-like liquid crystal or the like, and subjected to roller rubbing or UV exposure, etc. The alignment is performed to obtain a phase difference film p having a phase difference. In addition, the optical film (dry film) obtained by the above method has good optical properties such as low haze, low yellowness index, and visible light. Range (wavelength 400~700 nm) with high light penetration Degree (>9〇%) and high Abbe number (ie low wavelength dependence), so it can be directly applied as an optical film substrate or an optical film. In other words, the functional optical film of the present invention can be applied. The photoelectric plane displays $, for example, above LCD, (4), OLED or PLED. The optical film prepared by mixing PMMA with solvent casting film technology of the invention has many advantages: 1. good heat resistance, moderate mechanical properties, low photoelasticity = Coefficient with good optical properties f, for example: low haze, low yellowing index, South Abbe number, high penetration in the visible range (wavelength 4〇〇~7〇〇N) (>90% ) and optical film with uniform film surface properties (such as thickness, surface roughness, etc.); 2) can avoid material instability caused by melt blending or thermoplastic processing; 3 · water absorption and transparency of the towel Can effectively solve the problem of optical film optical properties variation; 4 • Easy process. In the optical film of the present invention, PMMA rubber particles formed by coating a rubber elastic material with PMMA and/or 1298340 or a substituted functional group of PMMA and/or PMMA may be further added, wherein the rubber elastic material may be Select butyl acrylate and/or polymethyl α methacrylate PMMA P〇ly (methyl methacrylate) and/or styrene, and the rubber elastic material has a particle size smaller than i 〇 Micron can even be further nanometer scale. Further, the amount of the PMMA rubber particles added is 2·5 to 50%. Therefore, the mechanical properties of the optical film can be enhanced, including properties such as improved elongation.

In the optical film of the present invention, silica may be further added, and the alumina may be added in the optical film process, and the convenient side is convenient.

The solvent and the alumina are mixed first, followed by the subsequent PMMA.

Mixing procedure. In addition, for the addition of alumina, it is also possible to add alumina together with pMMA in the PMMA particle blending procedure. Furthermore, it is also possible to mix the above-mentioned alumina after the PMMA mixing process. The weight percentage of the added alumina to the optical film may be a preferred range of Q5 %. The invention is described above by way of a preferred embodiment, and is not intended to limit the scope of patent rights claimed herein. The scope of patent protection shall depend on the scope of the patents attached to the second and the scope of (4). Any modification or design made by the skill of the art in the field without departing from the spirit or scope of the patent, and the invention shall be included in the following patent application. Within the scope. BRIEF DESCRIPTION OF THE DRAWINGS The above discussion, as well as the advantages of the present invention, will be readily understood by reference to the following detailed description. 1 is a flow chart showing the production of the optical film of the present invention; FIG. 2 is a graph showing the PMMA test result of the present invention; and FIG. 3 is a view showing the test of adding the PMMA film of the present invention to bauxite. Result chart.

[Explanation of main component symbols] Step 101 Select PMMA polymer and solvent Step 102 Form a solution system by solvent blending technique and carry out stability test Step 103 Scraper coating film formation Step 104 Film drying

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Claims (1)

1298340 X. Patent Application Range: Announcement 1 1. An optical film manufacturing method comprising: selecting at least one PMMA, a substituted functional group of PMMA, and any of the foregoing various PMMA blends; mixing and a solvent Mixing to form a mixed solution; distributing the mixed solution on a substrate; and performing a heat treatment to form an optical film. 2. The method of producing an optical film according to the first aspect of the invention, wherein any one of PMMA, a substituted functional group of PMMA, and a PMMA blend is blended with 20 to 40% by weight. 3. The method of producing an optical film according to claim 1, wherein the heat treatment comprises the steps of: heating the mixed solution to a first temperature, and stirring at the first temperature until the mixed solution The particles are completely dissolved; φ The mixed solution is poured onto a glass substrate, and the mixed solution on the glass substrate is dried to form an optical film. 4. The method for producing an optical film according to item 3 of the patent application, wherein the residual amount of the solvent is less than 1%. 5. The method of producing an optical film according to claim 1, wherein the functional group is a methyl group. 6. The method for producing an optical film according to claim 5, wherein the PMMA substituted with a functional group is selected from the group consisting of ethyl, propyl, isopropyl, n-butyl 16 1298340, isobutyl, and neobutyl. The n-hexyl group, the isohexyl group, the cyclohexyl group, and several of the aforementioned functional groups replace the methyl group of PMMA. 7. The method of producing an optical film according to claim 1, wherein the solvent is selected from any one of toluene, acetone, and methyl acetate. 8. The method for producing an optical film according to claim 1, wherein the blending system selects a polymer, a small molecule, a plasticizer, a uv absorber, an antidegradant, and a nanoparticle blend. Any type. 9. The method for producing an optical film according to item 8 of the patent application, wherein the nano-sized particles have a particle diameter of less than 100 nm. In the method of producing an optical film according to Item 1, wherein the solvent is selected from any one of an aromatic, a naphthene, an ether, an ester, and a ketone. / U, 12, two == the first " item of optical film manufacturing method wherein the ring 13, 14, such as the application of the general line H) of the silk film manufacturing method is selected from diethyl ether and tetrahydrofuran The ether-type of the optical film of the first aspect of the invention is selected from the group consisting of methyl acetate and any ester in ethyl acetate, wherein the ether is the same as the ester of the patent. The optical film of the item is selected from the group consisting of acetone, methyl ethyl ketone and / 'where the ketone oxime is the same. A method of producing an optical film according to claim 10, wherein the thickness of the optical film is between 20 and 200 μm. 17. The method for producing an optical film according to claim 1, wherein the optical film is selected for use as an optical film substrate for an LCD, an LED, an OLED or a PLED, and a protective film for an optical film. 18. The method of producing an optical film according to claim 1, wherein the mixed solution is formed by a solvent blending technique. Φ 19. The method for producing an optical film according to the first aspect of the invention, wherein the mixed solution is distributed on the substrate by means of a solvent cast film. 20. The method for producing an optical film according to claim 19, wherein the solvent casting method is selected from the group consisting of blade coating, wire bar coating, reverse or co-roll coating, air curtain coating, Any of wheel coating, engraving coating, dip coating, spin coating, slit coating, extrusion coating, curtain coating, extrusion molding, and injection molding. 21 22 The method for producing an optical film according to Patent Application No. β, wherein the substrate is a glass substrate, a plastic substrate, a mirror steel plate, a mirror steel strip, and a material of a synthetic polymer having a good uniformity. For example, in the 21st 苜 苜 专利 , , , , , , , , 员 员 员 员 员 员 员 员 员 员 员 员 员 员 员 员 员 员 员 员 员 员 员 员 员 员 员 员 员 员 员 员 员 员 员 员 员 员 员 员 员 员 员 员'i » TAn ^ Bay' and the natural fiber system is selected from any of CA, DAC and TAC. For example, the method for preparing an optical film in which the first solution of the patent range is distributed on the substrate, wherein the mixing degree is 150 micrometers (μπι)~ΐ2〇〇(μηι) micro 18 23 1298340 24, as claimed The method for fabricating the optical film of the first aspect, further comprising coating a material such as a discotic liquid crystal on the optical film, and selecting to perform alignment by any one of roller rubbing and UV exposure, thereby obtaining a position having a phase difference. Phase difference optical film. 25. The method of producing an optical film according to claim 1, wherein the heat treatment irradiates the mixed solution on the substrate with UV light. 26. The method for producing an optical film according to claim 1, wherein a particle formed by coating a rubber elastic material with any one of PMMA, PMMA substituted with a functional group, and various #PMMA blends is further added. [27] The method for producing an optical film according to claim 26, wherein the rubber elastic material is selected from the group consisting of butyl acrylate, poly-α-chloromethyl acrylate #PMMA Poly, styrene, and the foregoing rubber elastic materials. mixture. 28. The method of producing an optical film according to claim 26, wherein the rubber elastic material has a particle size of less than 10 micrometers. #29. The method for producing an optical film according to claim 26, wherein the rubber elastic material has a particle size of less than 100 nm. 30. The method for producing an optical film according to claim 26, wherein the rubber elasticity is coated with any one of PMMA, PMMA substituted with functional group, and various PMMA blends in an amount of 2.5 to 50%. Material. 31. The method for producing an optical film according to claim 1, wherein the alumina is further added to the process, wherein the alumina is cerium oxide. The method for producing an optical film according to claim 31, wherein the amount of alumina added is selected from any one of 0.5% to 15% by weight of the optical film. 33. The method for producing an optical film according to claim 32, wherein the added alumina system is mixed with the solvent to provide a subsequent PMMA mixing process. 34. The method for producing an optical film according to claim 32, wherein the added alumina is added to the PMMA particle mixing process, and the I solvent is added together with the PMMA. 35. The method for producing an optical film according to item 32 of the patent application, wherein the added earth is mixed in the PMMA mixing process. 20