Preparation method of 3D film

Abstract

The invention provides a preparation method of a 3D film, and relates to the technical field of optical film preparation, and the preparation method comprises the following steps: S1, coating a liquid crystal material; s2, photo-orientation curing is carried out; s3, preparing a 1 / 2 phase difference film; and step S4, transfer printing. Patterning preparation of the phase difference film is achieved through the synergistic effect of light orientation curing and hot-pressing stripping, so that the 1 / 2 wave plate manufacturing process is optimized, and the preparation efficiency and quality are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of optical film preparation, and in particular to a method for preparing a 3D optical film by preparing a patterned phase difference film through photo-orientation and imprint peeling technology. Background Art

[0002] Among the current mainstream 3D display technologies, polarized 3D technology holds a prominent position due to its superior overall performance. This technology leverages the "vibration direction" of light to create stereoscopic vision. Its core principle is to decompose the original image into two components: vertically polarized light and horizontally polarized light. The left and right lenses of the 3D glasses, each with its own polarization orientation, receive the corresponding images, ultimately synthesizing a three-dimensional image in the brain. This technical solution excels in color reproduction with minimal color loss, accurately reproducing the original image's colors almost identical to their original values, providing viewers with a realistic and detailed visual experience. Furthermore, its stereoscopic effect is outstanding, with a wide viewing angle range, ensuring a stable 3D experience even from off-center viewing angles. Importantly, the accompanying passive polarized glasses are inexpensive, comfortable to wear, contain no electronic components, and generate no radiation, significantly enhancing user comfort and safety. As a result, this technology has become a mainstream technology in the current market, finding widespread application in television, film projection, education, and other fields.

[0003] However, in the actual application of polarized 3D technology, there are many problems that need to be solved in the preparation process of its key component 1 / 2 phase difference film. At present, the preparation of 1 / 2 phase difference film mainly adopts the method of full-plate coating and then mechanically cutting the stripes with specific dot pitch. This process first requires the entire surface of the substrate to be coated. After the coating material is solidified, the required specific dot pitch stripes are obtained by mechanical cutting. In this process, since cutting can only obtain stripes of specific shapes and sizes, a large amount of uncut parts becomes waste, resulting in serious material loss, which not only causes a huge waste of resources, but also significantly increases production costs. From the perspective of processing efficiency, the traditional scribing process has obvious limitations. Mechanical cutting requires processing the coated material piece by piece, and the cutting of each piece requires precise alignment and operation, which makes the processing efficiency low and difficult to meet the needs of large-scale mass production. In large-scale production, this low efficiency directly leads to the extension of the production cycle and the inability to quickly respond to changes in market demand. In addition, the traditional scribing process also has many defects in processing quality. During the mechanical cutting process, due to the contact and friction between the tool and the material, the edges of the stripes are prone to curling. This edge defect will seriously affect the optical properties of the phase difference film. Edge curling will cause polarized light to scatter or refract when passing through the film, destroying the integrity of the polarization state, thereby affecting the display effect of 3D images, and may cause problems such as blurred images and ghosting. At the same time, these defects will also reduce the qualification rate of the product, requiring additional testing and screening processes, further increasing manpower and time costs. In summary, the existing 1 / 2 phase difference film preparation process has obvious deficiencies in terms of material utilization, processing efficiency and product quality, resulting in a large waste of manpower and resources, making production costs high, and restricting the further development and application of polarization 3D technology.

[0004] Therefore, developing a method for preparing 3D films that can solve the above problems is of great practical significance. Summary of the Invention

[0005] The main purpose of the present invention is to provide a method for preparing a 3D film, which realizes the one-piece molding of a patterned phase difference film through the innovation of precise temperature control imprinting and self-peeling process. This one-piece molding process does not require mechanical cutting after full-plate coating, which fundamentally avoids the loss of a large amount of material. At the same time, it simplifies the production process, eliminates multiple links such as cutting and screening, greatly improves processing efficiency, and helps to achieve large-scale mass production. Moreover, due to the use of precise temperature control and self-peeling process, the edge quality of the film can be effectively guaranteed, avoiding the generation of defects such as edge curling in the traditional slicing process, while maintaining the integrity of the polarization state, reducing production costs, and providing strong technical support for the further promotion and application of polarization 3D technology.

[0006] To achieve the above objectives, the present invention provides a method for preparing a 3D film, comprising the following steps: Step S1, coating liquid crystal material: placing a substrate on a transmission platform, and a liquid crystal coating machine uniformly coating the liquid crystal material on the surface of the substrate; the liquid crystal material formed on the substrate is baked in an oven unit through the transmission platform to remove the solvent in the liquid crystal solution; Step S2, photo-alignment curing: the liquid crystal material baked in step S1 is irradiated with a UV lamp in a curing unit to achieve photo-alignment curing; Step S3, Preparation of 1 / 2 Phase Difference Film: The solidified liquid crystal material is transported to an imprinting and peeling platform. The heating platform has stripes with the required heating point distance. The heating area is the edge of the heating point distance stripes, and heating rods are built in all four sides. Under appropriate heating temperature and pressure, the heated area contacts the liquid crystal film, and the adhesion between the liquid crystal in the contact area and the substrate film material is reduced. When the heating platform is lifted, the liquid crystal layer in the heated area is selectively peeled from the substrate, forming the desired patterned stripe structure, while the unheated area remains intact and attached, ultimately obtaining a high-precision 1 / 2 phase difference film. Step S4, transfer: After the heated platform peels off the liquid crystal film, it moves to the top of another roll film, which has been pre-treated and has adhesion to the liquid crystal film; after the platform descends, the liquid crystal film and the film material are attached, the adsorption holes stop adsorption, and the liquid crystal film is then transferred to the surface of the film material to form a 1 / 2 phase difference film.

[0007] Preferably, the substrate in step S1 is a coil, which is any one of PET, TAC, and PC.

[0008] Preferably, the surface of the substrate in step S1 is pre-treated so that when other adhesive objects come into contact with the surface material, the material can be easily peeled off from the surface.

[0009] Preferably, the pretreatment is coating a release agent.

[0010] Preferably, the liquid crystal material is a mixture containing monomeric liquid crystals, including monomeric liquid crystals, a chiral agent, and an organic solvent.

[0011] Preferably, the substrate is pre-coated with an alignment film having a desired orientation angle for the liquid crystal before coating the liquid crystal material.

[0012] Preferably, the coating method is any one of slit coating, gravure printing and screen printing.

[0013] Preferably, the coating thickness of the liquid crystal material is 1-10 μm.

[0014] Preferably, the baking temperature in step S1 is 70-80°C.

[0015] Preferably, the wavelength of the UV lamp in step S2 is 365 nm, and the curing time is 10-30 s.

[0016] Preferably, the heating platform in step S3 is provided with heating point distance stripes with different point pitches, and are arranged alternately with this point pitch; a slide rail is provided at the top of the heating point distance stripes, which can be adjusted accordingly according to the point pitch of the heating rod; the heating rod is a segmented structure, which can be freely extended and retracted to form different heating point pitches; the heating platform can move parallel to the cross bar; and an adsorption micropore is provided in the middle of the heating point distance stripes to facilitate the adsorption and processing of the peeled liquid crystal layer.

[0017] Preferably, the heating temperature in step S3 is 70-90°C.

[0018] Preferably, the heating point is a protruding heating module with stripes, which is moved by a built-in pulley, and insulating materials are filled between adjacent heating areas.

[0019] Preferably, the other roll film in step S4 is any one of PET, TAC, and PC.

[0020] Due to the application of the above technical solution, the present invention has the following beneficial effects: the present invention realizes the one-piece molding of the patterned phase difference film through the liquid crystal hot embossing peeling technology, while maintaining the integrity of the polarization state, compared with the traditional full-plate coating and then mechanical cutting process, it can greatly reduce material loss and improve production efficiency, solve the problems of low processing efficiency and easy curling of edges in the traditional scribing process, simplify the production process, and reduce production costs. The patterned stripes of the phase difference film prepared have high dimensional accuracy and good optical uniformity, and the process is applicable to a variety of optical substrates and liquid crystal systems. The parameters can be flexibly adjusted to adapt to different display technologies, reduce pollution, and have significant industrial application value and market prospects. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 Flow chart of the method for making a 3D film of the present invention; Figure 2 Schematic diagram of the wave plate imprinting process of the present invention; Figure 3 Schematic diagram of the hot stamping platform in Example 2; Among them, 101 is a coating device; 102 is a baking unit; 103 is a curing unit; 104 is an imprinting and peeling platform; 105 is a roll base film; 201 is a hot imprinting platform; 202 is an adsorption micropore; 203 is a heating rod; 204 is a 1 / 2 phase layer; 205 is a thermal insulation material. DETAILED DESCRIPTION

[0022] The following description is intended to disclose the present invention so that those skilled in the art can implement the present invention. The preferred embodiments described below are merely examples, and those skilled in the art may conceive of other obvious variations.

[0023] Example 1: Figure 1-2 , a method for preparing a 3D film, comprising the following steps: Step 1: Place the substrate on the platform, and the coating device 101 evenly coats the liquid crystal material on the surface of the substrate with a thickness of 1-2 μm; Step 2: The liquid crystal material is transported to the baking unit 102 and baked at 70° C. for 60 seconds to remove the solvent in the liquid crystal solution; Step 3: The liquid crystal material reaches the curing unit 103 through the transmission platform and is cured by a 365nm UV lamp for 10 seconds to achieve photo-alignment. Step 4: The liquid crystal film is precisely positioned under the hot stamping platform 201 via the transfer platform. The edge of the hot stamping platform 201 is a heating area, and the heating temperature is precisely controlled at 80°C by the heating rod 203. Under the action of the stamping pressure of 0.5-1MPa, the hot stamping platform 201 maintains continuous stamping contact with the liquid crystal film for 5 seconds; Step 5: After precise temperature control and pressure, the adhesion between the liquid crystal layer and the base film in the contact area of ​​the hot embossing platform 201 is reduced. The central area of ​​the hot embossing platform 201 is provided with adsorption micropores 202. Through the rapid lifting action of the hot embossing platform 201, the liquid crystal layer under heat peeling is adsorbed, achieving selective peeling of the liquid crystal in the specified area, and ultimately forming a liquid crystal stripe pattern with precise spacing, obtaining a 1 / 2 phase layer 204 that meets the design requirements; Step 6: After the peeling is completed, the hot stamping platform 201 moves to the top of the roll base film 105. After the platform descends, it is in contact with the base film for 5 seconds. The adsorption micropores 202 stop adsorption, and the liquid crystal film is then transferred to the surface of the roll base film 105 to form a 1 / 2 phase layer.

[0024] Example 2: Figure 3 The heating area of ​​the hot stamping platform 201 is stripes arranged alternately with the same point distance, and is on the same plane as the platform, wherein the middle of each heating point and stripe is filled with heat insulation material 205.

[0025] The specific embodiments described above further illustrate the objectives, technical solutions and beneficial effects of the present invention in detail. It should be understood that the above are only specific embodiments of the present invention and are not intended to limit the present invention. Any modifications, equivalent substitutions, improvements, etc. made within the spirit and principles of the present invention should be included in the scope of protection of the present invention.

Claims

1. A method for preparing a 3D film, characterized in that: The steps include: Step S1, coating liquid crystal material: placing a substrate on a transmission platform, and a liquid crystal coating machine uniformly coating the liquid crystal material on the surface of the substrate; the liquid crystal material formed on the substrate is baked in an oven unit through the transmission platform to remove the solvent in the liquid crystal solution; Step S2, photo-alignment curing: the liquid crystal material baked in step S1 is irradiated with a UV lamp in a curing unit to achieve photo-alignment curing; Step S3, Preparation of 1 / 2 Phase Difference Film: The solidified liquid crystal material is transported to an imprinting and peeling platform. The heating platform has stripes with the required heating point distance. The heating area is the edge of the heating point distance stripes, and heating rods are built in all four sides. Under appropriate heating temperature and pressure, the heated area contacts the liquid crystal film, and the adhesion between the liquid crystal in the contact area and the substrate film material is reduced. When the heating platform is lifted, the liquid crystal layer in the heated area is selectively peeled from the substrate, forming the desired patterned stripe structure, while the unheated area remains intact and attached, ultimately obtaining a high-precision 1 / 2 phase difference film. Step S4, transfer: After the heated platform peels off the liquid crystal film, it moves to the top of another roll film, which has been pre-treated and has adhesion to the liquid crystal film; after the platform descends, the liquid crystal film and the film material are attached, the adsorption holes stop adsorption, and the liquid crystal film is then transferred to the surface of the film material to form a 1 / 2 phase difference film.

2. The method for preparing a 3D film according to claim 1, wherein: The substrate in step S1 is a coil, which is any one of PET, TAC, and PC.

3. The method for preparing a 3D film according to claim 1, wherein: In step S1, the surface of the substrate is pretreated; the pretreatment is coating a release agent.

4. The method for preparing a 3D film according to claim 1, wherein: The liquid crystal material is a mixture containing monomeric liquid crystals, including monomeric liquid crystals, a chiral agent and an organic solvent; the substrate is pre-coated with an alignment film having a desired orientation angle for the liquid crystals before coating the liquid crystal material.

5. The method for preparing a 3D film according to claim 1, wherein: The coating method is any one of slit coating, gravure printing and screen printing.

6. The method for preparing a 3D film according to claim 1, wherein: The coating thickness of the liquid crystal material is 1-10 μm.

7. The method for preparing a 3D film according to claim 1, wherein: The baking temperature in step S1 is 70-80° C.; the wavelength of the UV lamp in step S2 is 365 nm, and the curing time is 10-30 seconds.

8. The method for preparing a 3D film according to claim 1, wherein: The heating platform in step S3 is provided with heating point distance stripes with different point pitches, and are arranged alternately at this point pitch; a slide rail is provided at the top of the heating point distance stripes, which can be adjusted accordingly according to the point pitch of the heating rod; the heating rod is a segmented structure, which can be freely extended and retracted to form different heating point pitches; the heating platform can move parallel to the cross bar; adsorption micropores are provided in the middle of the heating point distance stripes, which are convenient for adsorbing and processing the peeled liquid crystal layer; the heating temperature in step S3 is 70-90°C; the heating point distance stripes are raised heating modules, which are moved by built-in pulleys, and insulating materials are filled between adjacent heating areas.

9. The method for preparing a 3D film according to claim 1, wherein: The other roll film in step S4 is any one of PET, TAC, and PC.

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