CN-122011656-A - Photosensitive resin for embossed film based on photo-curing 3D printing, embossed film and preparation method

CN122011656ACN 122011656 ACN122011656 ACN 122011656ACN-122011656-A

Abstract

The invention discloses a photo-sensitive resin for a photo-curing 3D printing embossed film, the embossed film and a preparation method thereof, wherein the photo-sensitive resin comprises 30% -80% of polyurethane acrylic ester, 10% -60% of reactive diluent, 0.5% -10% of photo-sensitive resin, 0.01% -0.3% of polymerization inhibitor, 0.05% -0.5% of release agent and 0.05% -3% of defoaming agent. The embossing film comprises a microstructure layer which is cured by photosensitive resin, and a micro-scale regularly arranged pattern which is printed after being designed by a photo-curing 3D printing technology through a pre-micro-structure pattern model. According to the invention, by adopting a photocuring 3D printing technology, personalized customization of embossed films with different microstructure patterns can be realized rapidly, and meanwhile, the formula of photosensitive resin is adjusted, so that the embossed film with excellent mechanical properties and lower tearing and releasing force is realized.

Inventors

ZHENG SIYAO
LIU RUILIN
SHEN YANG
Luo Yiwan
FENG YUPU
SHI YING
XIA MENG

Assignees

武汉瑞普赛技术有限公司

Dates

Publication Date: 20260512
Application Date: 20260105

Claims (10)

1. The photo-sensitive resin for the photo-curing 3D printing embossed film is characterized by comprising 30-80% of polyurethane acrylic ester, 10-60% of active diluent, 0.5-10% of photo-sensitive resin, 0.01-0.3% of polymerization inhibitor, 0.05-0.5% of release agent and 0.05-3% of defoaming agent.
2. The photosensitive resin for a photo-curing 3D printing embossed film according to claim 1, wherein the urethane acrylate is polyester urethane acrylate or polyether urethane acrylate, and the mass ratio of the urethane acrylate to the photosensitive resin is 45% -70%.
3. The photosensitive resin for the photo-curing 3D printing embossed film according to claim 1, wherein the reactive diluent is one or more of hydroxyethyl acrylate, isobornyl acrylate, 1, 6-hexanediol diacrylate, trimethylolpropane triacrylate, lauryl acrylate, lauryl methacrylate and isodecyl acrylate, the mass ratio of the reactive diluent to the photosensitive resin is 25% -50%, the photoinitiator is a cracking free radical initiator, and the mass ratio of the photoinitiator to the photosensitive resin is 0.5% -5%.
4. The photosensitive resin for the photo-curing 3D printing embossed film according to claim 1, wherein the polymerization inhibitor is one or two of hydroquinone, p-methoxyphenol, 2, 6-di-tert-butyl-p-cresol, p-benzoquinone, 2, 6-tetramethylpiperidine-1-oxygen free radical, xanthone and p-hydroxyanisole, the polymerization inhibitor accounts for 0.01% -0.1% of the mass of the photosensitive resin, the release agent is one of polydimethylsiloxane, modified organosilicon, perfluoropolyether, fluorine surfactant, zinc stearate and calcium stearate, the release agent accounts for 0.05% -0.1% of the mass of the photosensitive resin, the defoamer is one of modified organosilicon, polyether modified polymer and fluorine modified polyacrylate, and the defoamer accounts for 0.05% -2% of the mass of the photosensitive resin.
5. The embossed film for light-cured 3D printing is characterized by comprising a base material layer, an undercoat layer, a microstructure layer and a protective film layer which are sequentially arranged from bottom to top, wherein the microstructure layer is formed by curing the photosensitive resin according to any one of claims 1 to 4.
6. The photo-curable 3D printed embossed film according to claim 5, wherein the micro-structured layer is a micro-sized regularly arranged pattern printed by a photo-curable 3D printing technique after design by a pre-micro-structured pattern model.
7. The photo-curing 3D printing embossing film according to claim 6, wherein the pattern of the microstructure layer is a pattern with regular geometric arrangement, the thickness of the microstructure pattern layer is 20-80 μm, the diameter of the microstructure pattern is 20-80 μm, the depth is 5-35 μm, the number of arrangement lines is 320-1300, the arrangement included angle is 60 ° or 45 ° or 30 °, and the dimensional accuracy of the microstructure features is not more than 2 μm.
8. The photo-curing 3D printing embossing film according to claim 5, wherein the substrate layer is a plastic substrate or a metal substrate, the substrate layer is a corona PET substrate with a thickness of 100-300 μm, the primer layer is a polyester primer with a thickness of 1-5 μm, and the protective film is a polyethylene protective film with a thickness of 30-60 μm.
9. The preparation method of the 3D printing embossed film based on photo-curing is characterized by comprising the following steps of: Firstly, preparing photosensitive resin, namely weighing polyurethane acrylic ester, an active diluent, a photoinitiator, a polymerization inhibitor, a release agent and a defoaming agent according to a formula, uniformly mixing at a set temperature, a set stirring speed and a set time to form a photosensitive resin mixture, and then filtering, heating and defoaming the photosensitive resin mixture to ensure that the resin viscosity of the photosensitive resin mixture is 200-1500 mPas (25 ℃); Step two, converting the planar design of the microstructure layer into a 3D stereoscopic model, slicing, and setting the conditions of thickness, exposure time, power and ultraviolet wavelength of a printing layer; Filling the photosensitive resin in the first step into a resin groove of the 3D printing equipment, printing a designed microstructure pattern on the base material layer with the bottom coating, and circularly printing according to preset parameters and a model until the model is completely presented to form an embossed film; and fourthly, coating a layer of protective film on the surface of the embossed film.
10. The method for preparing a patterned film according to claim 9, wherein the method further comprises performing ultrasonic cleaning to remove micro-supporting structures generated during printing according to a set ultrasonic power and time, and performing secondary ultraviolet exposure of the patterned film according to a set ultraviolet wavelength and time.

Description

Photosensitive resin for embossed film based on photo-curing 3D printing, embossed film and preparation method Technical Field The invention relates to the technical field of manufacturing of alignment film printing plates. More particularly, the present invention relates to a photocurable 3D printing embossed film-based photosensitive resin for alignment film printing plate production, an embossed film and a method of producing the same. Background Alignment film printing plates are key process tools in the manufacture of Liquid Crystal Displays (LCDs) for uniformly coating alignment film materials (e.g., polyimide PI liquid) in a specific pattern on a glass substrate to form an alignment film (ALIGNMENT LAYER). Alignment films are used in LCDs to control the Alignment of liquid crystal molecules, which are aligned in a specific direction by a rubbing or photoalignment (Photo-Alignment) process, ensuring display uniformity and response speed. The flexible printing method with higher material utilization rate, lower cost and continuous printing can be adopted in the alignment film printing process of the liquid crystal display, the printing ink transfer layer of the flexible printing plate is soft and elastic crosslinked resin, and the surface of the resin is a rough surface with certain roughness for bearing the ink which needs to be transferred in the printing process, namely the alignment liquid. Publication CN111221186 (wuhan rapier technology limited) describes a method of making an alignment film printing plate ink transfer layer by an embossing transfer process. Embossed film with a pattern of differently regularly arranged microstructures is a critical material in this process to form this matte side. At present, the embossing film with different microstructure patterns is mainly manufactured by a microstructure embossing method, namely, a metal master mold with microstructure patterns is manufactured by precision machining (such as diamond turning, photoetching or laser direct writing), ultraviolet (UV) curing resin is coated on a transparent substrate (such as PET and PMMA), the resin is embossed by the metal master mold, and the mold is separated after the microstructure surface is formed by UV light irradiation curing. The process method relying on master die stamping is low in molding precision, single in pattern structure, high in personalized customization cost and long in period. 3D printing technology, also known as additive manufacturing or rapid prototyping technology, is a technology that uses Computer Aided Design (CAD) to convert digital models into entities by stacking materials layer by layer. Compared with the traditional manufacturing method (such as material reduction manufacturing and equal material manufacturing), the 3D printing technology does not need a die and a complex manufacturing flow, rapidly manufactures objects with complex shapes and structures which are difficult to realize by the traditional method, and realizes low-cost personalized customization. Photo-curing 3D printing becomes one of the most widely-studied printing technologies at present due to the characteristics of high precision, high efficiency and low energy consumption. Common photo-curing 3D printing techniques are mainly Digital Light Processing (DLP), stereolithography (SLA), surface projection micro-stereolithography (pμsl) and two-photon polymerization (2 PP). Although these 4 technologies are different in process, photosensitive resin is used as a main consumable material. Photosensitive resin is the core of photo-curing 3D printing technology, and mainly consists of photosensitive oligomer, photoinitiator and reactive diluent. The curing mechanism is that the photoinitiator absorbs light energy under the irradiation of ultraviolet light, and decomposes to generate active groups (free radicals or cations), and then the photosensitive oligomer is initiated to undergo polymerization and crosslinking reaction, and the photosensitive resin is converted from a liquid state to a solid state. The existing photosensitive resin material for 3D printing has the defects of insufficient mechanical property, limited dimensional accuracy, poor weather resistance, environmental pollution and the like, and most materials cannot meet the requirements on the functionality of products in different application occasions. Disclosure of Invention The invention aims to provide a photo-sensitive resin for an alignment film printing plate manufacturing based on photo-curing 3D printing embossed film, an embossed film and a preparation method thereof, which solve the problems of single structure of the embossed film, higher personalized customization cost, insufficient functionality of the photosensitive resin and the like in the prior art, and can rapidly realize personalized customization of the embossed film with higher precision and different microstructure patterns by adopting a photo-curing 3D printing technology, an