Preparation system for high-matte polyester film

Abstract

The utility model discloses a preparation system for a high-matte-degree polyester film. The high-matte-degree polyester film is composed of a base material layer A, a surface matte layer B and a matte coating C, the preparation system can be used for efficiently and continuously preparing the low-matte polyester film and comprises a first mixer, a second mixer, a PET raw material tank, a silicon dioxide raw material tank, a polytetrafluoroethylene raw material tank, a polyethylene glycol raw material tank and a polymethyl methacrylate raw material tank, the first mixer is respectively connected with a PET raw material tank and a silicon dioxide raw material tank, and the second mixer is respectively connected with the PET raw material tank, a polytetrafluoroethylene raw material tank, a polyethylene glycol raw material tank and a polymethyl methacrylate raw material tank; the first mixer is connected with the main extruder, the second mixer is connected with the auxiliary extruder, the main extruder and the auxiliary extruder are connected with the thick sheet cooling mechanism, and the thick sheet cooling mechanism is connected with the longitudinal stretching mechanism and the transverse stretching mechanism; and a spraying mechanism, an ultraviolet irradiation mechanism, a heat setting mechanism and a winding mechanism are arranged at the downstream of the transverse stretching mechanism.

Description

TECHNICAL FIELD

[0001] The utility model relates to a kind of preparation system for high-matt polyester film. BACKGROUND

[0002] Matt film has great demand in packaging, label, decoration, printing and other fields. Generally, the reflectivity of film surface below 10% is considered to be matt; the reflectivity between 10% and 30% is considered to be semi-matt; and the reflectivity above 30% is generally considered to be glossy. The degree of matt is usually represented by glossiness, which is usually in the range of 0% to 100%. 0% represents complete dullness (such as matt surface), and 100% represents maximum glossiness (such as mirror surface). Glossiness is usually measured by a gloss meter. High-matt film generally refers to a surface glossiness below 10%, which has almost no gloss. Medium-matt film generally refers to a glossiness between 10% and 30%, which has a certain gloss but still maintains relatively low reflectivity. Low-matt film has a glossiness between 30% and 50%, which is relatively smooth and has obvious gloss but does not belong to the high-gloss category.

[0003] CN 114619745 B discloses a multi-layer structure matt polyester film, which includes a base film and a matt film. The intermediate layer is the base film, and the matt film is on both sides of the base film, obtained by co-extrusion technology. The raw material of the matt film includes a matt additive, which is a polymer grafted modified silica microsphere and a polystyrene microsphere. The polymer grafted modified monomer is (meth) acrylate and isobornyl acrylate.

[0004] The above-mentioned prior art matt film forms scattering of light inside the film layer by adding inorganic solid particles, reduces the direct reflection of the film layer to light of the same angle of incidence, and obtains a certain matt effect. While the solid particles scatter light, they also hinder the projection of light, thereby reducing the light transmission performance of the film. At the same time, although there is scattering of solid particles inside the film layer, the impact on the surface of the film is limited, and the roughness of the film surface is difficult to effectively reduce, and the smooth surface is difficult to reduce the light reflectivity. In addition, in order to obtain sufficient matt effect, the particle size of the added solid particles needs to reach a certain degree, and a sufficient amount is also needed. The addition of too many large-diameter solid particles will form cavities inside the matt layer during film stretching, reducing the density and strength of the matt layer, thereby causing the tear resistance of the outer matt layer to be insufficient and easily broken and cracked. Moreover, due to the porosity of the stretched film layer, it is easy for colorants to penetrate and present patches, and the texture of the outer surface will quickly decrease.

[0005] CN 110157032 A discloses a preparation method of high-matte matte polyester film. First, a polyester film is prepared and stretched, then acrylamide is coated on the surface, and the film surface is grafted and copolymerized with acrylamide by ultraviolet irradiation. Then, polyurethane paint and polyacrylate paint are coated on the surface of the matte polyester film, and the refractive index of the double-sided coating layer increases the light transmittance of the matte polyester film.

[0006] However, it is known that acrylamide (Acrylamide, referred to as AA) has good hydrophilicity. If acrylamide is polymerized with the polyester film under ultraviolet irradiation, the film surface should have better wetting performance, reduce the surface contact angle, make the liquid more easily spread on the film surface, and the film surface should become smoother and more difficult to become rough. In addition, the polymer chain of acrylamide forms a smooth and uniform coating on the surface of the PET film, which can fill the small recesses on the surface, so that the overall surface becomes smoother.

[0007] In addition, the prior art also lacks a special device or system for preparing high-matte polyester film, and cannot efficiently and continuously prepare low-matte polyester film. SUMMARY

[0008] The technical problem to be solved by the utility model is to provide a preparation system for high-matte polyester film to reduce or avoid the problems mentioned above.

[0009] To solve the above technical problems, the utility model provides a preparation system for high-matte polyester film, the high-matte polyester film is composed of a substrate layer A, a surface matte layer B and a matte coating C sprayed on the outer side of the surface matte layer B, the preparation system comprises a first mixer corresponding to the substrate layer A and a second mixer corresponding to the surface matte layer B, and the first mixer and the second mixer have a shared PET raw material tank; the inlet of the first mixer is connected with the PET raw material tank and a silicon dioxide raw material tank respectively, the inlet of the second mixer is connected with the PET raw material tank, a polytetrafluoroethylene raw material tank, a polyethylene glycol raw material tank and a polymethyl methacrylate raw material tank respectively; the outlet of the first mixer is connected with a main extruder, the outlet of the second mixer is connected with an auxiliary extruder, the outlets of the main extruder and the auxiliary extruder are connected with a thick sheet cooling mechanism, the outlet of the thick sheet cooling mechanism is connected with a longitudinal stretching mechanism, and the outlet of the longitudinal stretching mechanism is connected with a transverse stretching mechanism; a spraying mechanism and an ultraviolet irradiation mechanism are arranged downstream of the transverse stretching mechanism; a heat setting mechanism is arranged downstream of the ultraviolet irradiation mechanism, and a winding mechanism is arranged downstream of the heat setting mechanism.

[0010] Preferably, the inlet of the spraying mechanism is connected with a matte coating tank.

[0011] The high-matte polyester film prepared by the utility model has the advantages of anti-ultraviolet, anti-static, wear resistance and excellent matte effect, and is suitable for high-end applications such as polarizing sheet release film and optical device surface protection. The multi-layer structure and heat setting process guarantee size stability, adapt to high-temperature and high-humidity environment, and prolong service life. In addition, the utility model further provides a special system for preparing the high-matte polyester film, and the low-matte polyester film can be efficiently and continuously prepared. BRIEF DESCRIPTION OF DRAWINGS

[0012] The following drawings are only intended to illustrate and explain the present application, and do not limit the scope of the utility model.

[0013] Figure 1 The structure diagram of the high-matte polyester film according to one specific embodiment of the utility model is shown.

[0014] Figure 2 The structure diagram of the preparation system for the high-matte polyester film according to one specific embodiment of the utility model is shown. DETAILED DESCRIPTION

[0015] In order to have a clearer understanding of the technical features, purposes and effects of the utility model, the specific embodiments of the utility model will be described with reference to the drawings. In the drawings, the same components are denoted by the same reference numerals.

[0016] As shown in the drawings, Figure 1 The utility model discloses a kind of high-matte polyester films, by substrate layer A, surface matte layer B and matte coating C that is sprayed on the outside of surface matte layer B.

[0017] In one specific embodiment, the thickness of substrate layer A is 30-35 μm;The thickness of surface matte layer B is 12-15 μm;The thickness of matte coating C is 1-5 μm. Among them, when the thickness of matte coating C is preferably 1-3 μm, the matte effect of film does not significantly affect the transparency of film, and is used in the application requiring higher light transmittance. When the thickness of matte coating C is preferably 3-5 μm, it is suitable for occasions with higher requirements for low gloss, such as anti-glare purposes.

[0018] The total thickness of the high-matte polyester film of the utility model is preferably designed to be about 40-50 μm, so that the film meets the mechanical strength while maintaining flexibility and light transmittance. The thickness of matte coating C is 1-5 μm, which can ensure uniform distribution of the coating, while maintaining low gloss and wear resistance, without excessive impact on the mechanical properties of the substrate.

[0019] In another embodiment, the substrate layer A is composed of 79.5-80.5% by mass of polyethylene terephthalate (PET) and 19.5-20.5% by mass of silica (Si02) nanoparticles.

[0020] Further, the polyethylene terephthalate preferably uses optical grade PET particles or chips, preferably raw material products with a melting point of about 255°C, such as high-purity optical grade PET provided by Toray, DuPont, etc., with a light transmittance of more than 90%. The silica nanoparticles preferably use products with a particle size of 50-100 nm, such as Aerosil series of Evonik, such as Aerosil 200, or Cab-O-Sil series of Cabot.

[0021] In another embodiment, the surface matte layer B is composed of 78.5-82.5% by mass of polyethylene terephthalate (PET), 2.5-3.5% by mass of polytetrafluoroethylene (PTFE), 9.5-10.5% by mass of polyethylene glycol (PEG), and 4.5-8.5% by mass of polymethyl methacrylate (PMMA).

[0022] Further, the polyethylene terephthalate preferably uses optical grade PET particles or chips, preferably raw material products with a melting point of about 255°C, such as high-purity optical grade PET provided by Toray, DuPont, etc., with a light transmittance of more than 90%. The polytetrafluoroethylene preferably uses micropowder particles with a particle size of ≤1 μm, such as Dyneon TM PTFE of 3M or Solvay PTFE series. The polyethylene glycol preferably uses products with a molecular weight range of 2000-6000, such as PEG products produced by Merck or Sigma-Aldrich, etc. The polymethyl methacrylate preferably uses PMMA series products provided by Evonik (such as ), or PMMA products of LG Chemical.

[0023] In another embodiment, the matte coating layer C is composed of the following raw materials with the following mass fractions: 59.5-60.5% of polyurethane acrylate (PUA), 19.5-20.5% of silicone silica microparticles, 16.5-17.5% of tripropyloxy triethylene glycol acrylate (TMPTA), 1.5-2.5% of benzophenone (BP), 0.45-0.55% of polyether siloxane, and 0.45-0.55% of polydimethylsiloxane, which is cured by ultraviolet light.

[0024] Further specifically, the polyurethane acrylate (PUA) preferably adopts a product with a viscosity range of 3000-5000 cps, such as the polyurethane acrylate resin provided by BASF, Mitsubishi Chemical and the like; further preferably, the PUA suitable for UV curing coating, such as the Laromer series of Merck KGaA (Germany Merck Company). The silicone silica microparticle preferably adopts a product with a particle size of 3-5 μm, such as the Sipernat series of Degussa, or the Syloid series of Grace. The tripropoxy acrylate of triethylene glycol preferably adopts a product with a purity of greater than or equal to 98%, such as the high-purity TMPTA supplied by Sigma-Aldrich or Allnex. The benzophenone preferably has a spectral range of about 365 nm, with a purity of ≥ 99%. For example, the UV curing series product of IGM Resins or BASF. Both the polyether siloxane and the polydimethylsiloxane can adopt the products of BYK Chemical Company, such as the polyether siloxane can adopt BYK-333, and the polydimethylsiloxane can adopt BYK-016.

[0025] Further specifically, the coating material constituting the matte coating C can be prepared by the following process. For example, the polyurethane acrylate and TMPTA are mixed according to the mass ratio, and stirred at room temperature until completely dissolved, forming a uniform solution. The silicone silica microparticle is added to the above-mentioned solution, and stirred for 10-15 minutes to ensure uniform dispersion. The use of high-speed stirring equipment (about 1000 rpm) is better. The benzophenone, polyether siloxane, and polydimethylsiloxane are added in proportion, and slowly stirred for 5 minutes to completely dissolve each component. The solution is filtered with a 100-mesh filter screen to remove undispersed particles or impurities, ensuring the uniformity and transparency of the coating.

[0026] The matte coating material of the utility model adds the silicone silica microparticle and forms the surface rough structure, makes the glossiness of coating significantly reduce, reaches high matte effect. The crosslinking structure of PUA matrix resin and TMPTA improves the hardness and wear resistance of the coating. The composite structure of the silicone silica microparticle and PUA not only reduces the gloss, but also has the function of resisting ultraviolet rays, prolongs the service life of the film. The design and process of the coating material help to form a uniform and stable matte layer on the surface, ensure the low gloss effect, and at the same time enhance the durability of the film.

[0027] Further, the high-matte polyester film of the utility model can be prepared by the following process.

[0028] The raw materials constituting the substrate layer A and the surface matte layer B are weighed and respectively put into the respective mixing machines for melt blending, and the melting temperature is controlled at 250-270 DEG C.

[0029] The base material layer A is melt-extruded by a main extruder at 250-260℃, and the cooling roller temperature is 20℃. The surface matte layer B is melt-extruded by an auxiliary extruder at a temperature of 260-270℃, and the cooling roller temperature is 15℃. The two extruded film layers are simultaneously introduced into a cooling system to form a double-layer thick piece, and the cooling temperature of the thick piece is set to 15-20℃.

[0030] The double-layer thick piece is subjected to 3 times of longitudinal stretching at 85-90℃, and then subjected to 3.5 times of transverse stretching at 110-120℃.

[0031] The coating material forming the matte coating layer C is uniformly sprayed on the surface of the surface matte layer B, and the coating thickness is controlled to be 5-10μm. Then, the coating is treated by ultraviolet light initiation, the wavelength of the ultraviolet light is 365nm, the irradiation intensity is 300mW / cm 2 , the time is controlled to be 3 minutes, and the coating is cooled to room temperature to form the matte coating layer C.

[0032] Finally, the film forming the matte coating layer is heat-set at 200-210℃ for 5-10 seconds to ensure the stability of the layered structure and enhance the dimensional stability and durability of the film.

[0033] Corresponding to the above preparation process, the utility model also proposes a preparation system for preparing the above high-matte polyester film, as Figure 2 shown.

[0034] The preparation system of the utility model includes a first mixer 100 corresponding to the base material layer A and a second mixer 200 corresponding to the surface matte layer B, and the first mixer 100 and the second mixer 200 have a shared PET raw material tank 10; the inlet of the first mixer 100 is connected to the PET raw material tank 10 and a silicon dioxide raw material tank 11 respectively, and the inlet of the second mixer 200 is connected to the PET raw material tank 10, a polytetrafluoroethylene raw material tank 12, a polyethylene glycol raw material tank 13 and a polymethyl methacrylate raw material tank 14 respectively. By sharing the PET raw material tank 10, the number of equipment and the types of raw materials can be significantly reduced, which is beneficial to obtain a film layer with uniform quality.

[0035] The first mixer 100 corresponding to the base material layer A and the second mixer 200 corresponding to the surface matte layer B melt-blend the input raw materials; and then extrude respectively.

[0036] Further, the outlet of the first mixer 100 is connected to the main extruder 101, the outlet of the second mixer 200 is connected to the auxiliary extruder 201, and the outlets of the main extruder 101 and the auxiliary extruder 201 are connected to the thick sheet cooling mechanism 300. The base material layer A is extruded by the main extruder 101, the surface matte layer B is extruded by the auxiliary extruder 201, and then enters the thick sheet cooling mechanism 300 for cooling. The cooled thick sheet is then sequentially subjected to longitudinal stretching and transverse stretching.

[0037] The outlet of the thick sheet cooling mechanism 300 is connected to the longitudinal stretching mechanism 400, the outlet of the longitudinal stretching mechanism 400 is connected to the transverse stretching mechanism 500, and the downstream of the transverse stretching mechanism 500 is provided with the spraying mechanism 601 and the ultraviolet light irradiation mechanism 602.

[0038] The spraying mechanism 601 sprays matte paint on the surface of the surface matte layer B, and then the ultraviolet light irradiation mechanism 602 is used for irradiation treatment.

[0039] Further, the inlet of the spraying mechanism 601 can also be connected to the matte paint tank 600, which is used to continuously supply matte paint to the spraying mechanism 601 through the matte paint tank 600, so as to obtain the effect of high-quality continuous production.

[0040] The downstream of the ultraviolet light irradiation mechanism 602 is provided with the heat setting mechanism 701, and the downstream of the heat setting mechanism 701 is provided with the winding mechanism 700.

[0041] The polyester film prepared is subjected to performance test. Among them, the gloss, haze, and light transmittance of the film are tested by using BYK or HunterLab gloss meter and haze meter. The tensile strength and elongation at break are tested by using Instron tensile testing machine according to the ASTM standard specification. The ultraviolet aging performance is tested by using Q-SUN or UV test box of Atlas of Q-Lab, and setting for 500 hours of weather resistance.

[0042] The measurement standards of the related performance parameters are shown as follows.

[0043] Gloss test standard: ASTM D523, measured with 60° gloss meter. Haze test standard: ASTM D1003, measured with haze meter, tested the scattering effect, anti-glare performance of the film. Light transmittance test standard: ASTM D1003, measured with light transmittance tester, tested the light transmittance of the film under the effect of matte. Tensile strength test standard: ASTM D882, tested the durability of the film in machine direction (MD) and transverse direction (TD) using tensile tester. Elongation at break test standard: ASTM D882, characterized the flexibility and durability of the film. Coefficient of friction (COF) test standard: ASTM D1894, measured by coefficient of friction tester, tested the surface smoothness of the film. Surface hardness test standard: ASTM D3363, pencil hardness test, evaluated the scratch resistance of the coating, tested the wear resistance of the film during use. Anti-UV performance: maintained at least 90% above of light transmittance and gloss after 500 hours of exposure to ultraviolet light, tested whether the change rate exceeded 10%. Test standard: ASTM G154, ultraviolet aging test, simulated the stability under long-term exposure. Chemical resistance: resisted wiping with common chemical solvents such as ethanol, isopropanol, etc., whether there was obvious damage to the surface. Test standard: ASTM D5402, coating chemical resistance test, tested the stability of the surface matte layer. Matte coating adhesion test standard: ASTM D3359, tested the adhesion of the coating to the substrate using crosshatch method, tested the stability of the matte coating during use.

[0044] Example 1

[0045] The high-matte polyester film of this example was composed of a 32 μm thick substrate layer A, a 14 μm thick surface matte layer B, and a 3 μm thick matte coating layer C.

[0046] The substrate layer A contained 80.0% polyethylene terephthalate and 20.0% silica; the surface matte layer B contained 80.0% PET, 3.0% polytetrafluoroethylene, 10.0% polyethylene glycol, and 7.0% polymethyl methacrylate; the matte coating layer C was composed of 60.0% polyurethane acrylate, 20.0% silicone silica microparticles, 17.0% tripropoxy triethylene glycol acrylate, 2.0% benzophenone, 0.5% polyether siloxane, and 0.5% polydimethyl siloxane.

[0047] The film of Example 1 had a gloss of 5%, a haze of 28%, a light transmittance of 85%, a tensile strength of 146 MPa, an elongation at break of 128%, a coefficient of friction of 0.5, a surface hardness of 2H, a change in light transmittance and gloss of 5% after 500 hours of ultraviolet light aging, excellent resistance to common chemical solvents, and a matte coating adhesion of 5B.

[0048] Example 2

[0049] The high-matt polyester film of this example is composed of a 30 μm thick base layer A, a 12 μm thick surface-matt layer B, and a 1 μm thick matt coating layer C.

[0050] The base layer A contains 79.5% PET and 20.5% SiO2; the surface-matt layer B contains 78.5% PET, 2.5% PTFE, 10.5% PEG, and 8.5% PMMA; and the matt coating layer C contains 59.5% PUA, 20.5% silicone-silica microparticles, 16.6% TMPTA, 2.5% BP, 0.45% polyether siloxane, and 0.45% dimethicone.

[0051] The film of Example 2 has a glossiness of 4%, a haze of 31%, and a light transmittance of 83%; a tensile strength of 152 MPa and an elongation at break of 125%; a friction coefficient of 0.4 and a surface hardness of 2H; a change in light transmittance and glossiness of 6% after 500 hours of ultraviolet light aging; excellent resistance to common chemical solvents; and a matt coating adhesion of 5B.

[0052] Example 3

[0053] The high-matt polyester film of this example is composed of a 35 μm thick base layer A, a 15 μm thick surface-matt layer B, and a 5 μm thick matt coating layer C.

[0054] The base layer A contains 80.5% PET and 19.5% SiO2; the surface-matt layer B contains 82.5% PET, 3.5% PTFE, 9.5% PEG, and 4.5% PMMA; and the matt coating layer C contains 60.5% PUA, 19.5% silicone-silica microparticles, 17.4% TMPTA, 1.5% BP, 0.55% polyether siloxane, and 0.55% dimethicone.

[0055] The film of Example 3 has a glossiness of 6%, a haze of 26%, and a light transmittance of 84%; a tensile strength of 149 MPa and an elongation at break of 130%; a friction coefficient of 0.4 and a surface hardness of H; a change in light transmittance and glossiness of 7% after 500 hours of ultraviolet light aging; excellent resistance to common chemical solvents; and a matt coating adhesion of 5B.

[0056] Comparative Example 1

[0057] The base layer A is the same as in Example 1 and contains 80.0% PET and 20.0% SiO2.

[0058] The surface-matt layer B is the same as in Example 1 and contains 80.0% PET, 3.0% PTFE, 10.0% PEG, and 7.0% PMMA.

[0059] Matte coating C: change to 60.0% PUA, 20.0% silicone silica microparticles, 17.0% TMPTA, 0.5% polyether siloxane, 0.5% polydimethylsiloxane.

[0060] Performance data: gloss 8%, haze 24%, light transmission 82%; tensile strength 146 MPa, elongation at break 128%; coefficient of friction 0.5, surface hardness 2H; change in light transmission and gloss after 500 hours of UV aging 15%; matte coating adhesion not up to standard, only 3B.

[0061] Comparative Example 1 shows that, in the absence of benzophenone, the coating is not cured enough, the UV aging performance is significantly reduced, and the adhesion is reduced.

[0062] Comparative Example 2

[0063] Substrate layer A: same as Example 1, containing 80.0% PET and 20.0% SiO2.

[0064] Surface matte layer B: change to 80.0% PET, 3.0% PTFE, 17.0% PMMA (without PEG).

[0065] Matte coating C: same as Example 1, containing 60.0% PUA, 20.0% silicone silica microparticles, 17.0% TMPTA, 2.0% BP, 0.5% polyether siloxane, 0.5% polydimethylsiloxane.

[0066] Performance data: gloss 12%, haze 20%, light transmission 80%; tensile strength 140 MPa, elongation at break 110%; coefficient of friction 0.6, surface hardness 2H; change in light transmission and gloss after 500 hours of UV aging 10%; matte coating adhesion 5B.

[0067] Comparative Example 2 shows that, by removing PEG, the flexibility of the surface matte layer is reduced, and the gloss and friction performance are deteriorated.

[0068] Comparative Example 3

[0069] Substrate layer A: change to 90.0% PET and 10.0% SiO2.

[0070] Surface matte layer B: same as Example 1, containing 80.0% PET, 3.0% PTFE, 10.0% PEG, 7.0% PMMA.

[0071] Matte coating C: same as Example 1, containing 60.0% PUA, 20.0% silicone silica microparticles, 17.0% TMPTA, 2.0% BP, 0.5% polyether siloxane, 0.5% polydimethylsiloxane.

[0072] Performance data: gloss 10%, haze 18%, light transmission 88%; tensile strength 144 MPa, elongation at break 120%; friction coefficient 0.5, surface hardness 2H; UV aging 500 hours light transmission and gloss change 7%; matte coating adhesion 5B.

[0073] Comparative Example 3 shows that insufficient silica content in the substrate layer results in a decrease in haze and matte properties, and cannot effectively achieve high matte characteristics.

[0074] Comparative Example 4

[0075] Substrate layer A: changed to 85.0% PET and 15.0% SiO2.

[0076] Surface matte layer B: same as Example 2, containing 78.5% PET, 2.5% PTFE, 10.5% PEG, 8.5% PMMA.

[0077] Matte coating C: same as Example 2, containing 59.5% PUA, 20.5% silicone silica microparticles, 16.6% TMPTA, 2.5% BP, 0.45% polyether siloxane, 0.45% polydimethylsiloxane.

[0078] Performance data: gloss 6%, haze 28%, light transmission 84%; tensile strength 140 MPa, elongation at break 115%; friction coefficient 0.4, surface hardness 2H; UV aging 500 hours light transmission and gloss change 9%; matte coating adhesion 5B.

[0079] Comparative Example 4 shows that reducing the content of silica results in a decrease in mechanical strength and optical effect.

[0080] Comparative Example 5

[0081] Substrate layer A: same as Example 2, containing 79.5% PET, 20.5% SiO2.

[0082] Surface matte layer B: changed to 80.5% PET, 5.5% PTFE, 13.0% PEG (PMMA removed).

[0083] Matte coating C: same as Example 2, containing 59.5% PUA, 20.5% silicone silica microparticles, 16.6% TMPTA, 2.5% BP, 0.45% polyether siloxane, 0.45% polydimethylsiloxane.

[0084] Performance data: gloss 5%, haze 35%, transmission 81%; tensile strength 148 MPa, elongation at break 110%; coefficient of friction 0.6, surface hardness 2H; UV aging 500 hours, transmission and gloss change 10%; matte coating adhesion 5B.

[0085] Comparative Example 5 shows that removing PMMA and increasing PTFE improves abrasion resistance but results in insufficient flexibility and reduced optical effect.

[0086] Comparative Example 6

[0087] Substrate layer A: same as Example 2, containing 79.5% PET, 20.5% Si02.

[0088] Surface matte layer B: containing 78.5% PET, 2.5% PTFE, 13.5% PEG, 5.5% PMMA.

[0089] Matte coating C: same as Example 2, containing 59.5% PUA, 20.5% silicone silica microparticles, 16.6% TMPTA, 2.5% BP, 0.45% polyether siloxane, 0.45% polydimethylsiloxane.

[0090] Performance data: gloss 7%, haze 30%, transmission 82%; tensile strength 140 MPa, elongation at break 120%; coefficient of friction 0.5, surface hardness 2H; UV aging 500 hours, transmission and gloss change 8%; matte coating adhesion 5B.

[0091] Comparative Example 6: increasing PEG content improves flexibility but causes compromise in gloss and haze, overall effect is not as good as Example 2.

[0092] Comparative Example 7

[0093] Substrate layer A: same as Example 3, containing 80.5% PET and 19.5% Si02.

[0094] Surface matte layer B: changed to 80.0% PET, 6.5% PTFE, 9.5% PEG, 4.0% PMMA.

[0095] Matte coating C: same as Example 3, containing 60.5% PUA, 19.5% silicone silica microparticles, 17.4% TMPTA, 1.5% BP, 0.55% polyether siloxane, 0.55% polydimethylsiloxane.

[0096] Performance data: gloss 5%, haze 33%, transmission 80%; tensile strength 150 MPa, elongation at break 110%; coefficient of friction 0.7, surface hardness 3H; change in transmission and gloss after 500 hours of UV light aging 12%; matte coating adhesion 5B.

[0097] Comparative Example 7 shows that increasing PTFE improves hardness and abrasion resistance, but affects flexibility and optical properties.

[0098] Comparative Example 8

[0099] Substrate layer A: changed to 85.0% PET and 15.0% SiO2.

[0100] Surface matte layer B: same as Example 3, containing 82.5% PET, 3.5% PTFE, 9.5% PEG, 4.5% PMMA.

[0101] Matte coating C: same as Example 3, containing 60.5% PUA, 19.5% silicone silica microparticles, 17.4% TMPTA, 1.5% BP, 0.55% polyether siloxane, 0.55% polydimethylsiloxane.

[0102] Performance data: gloss 6%, haze 28%, transmission 86%; tensile strength 145 MPa, elongation at break 120%; coefficient of friction 0.5, surface hardness 2H; change in transmission and gloss after 500 hours of UV light aging 9%; matte coating adhesion 5B.

[0103] Comparative Example 8 shows that reducing silica increases transparency, but reduces scratch resistance, resulting in a slight decrease in optical effect.

[0104] Comparative Example 9

[0105] Substrate layer A: same as Example 3, containing 80.5% PET and 19.5% SiO2.

[0106] Surface matte layer B: changed to 79.5% PET, 2.5% PTFE, 14.5% PEG, 3.5% PMMA.

[0107] Matte coating C: same as Example 3, containing 60.5% PUA, 19.5% silicone silica microparticles, 17.4% TMPTA, 1.5% BP, 0.55% polyether siloxane, 0.55% polydimethylsiloxane.

[0108] Performance data: gloss 8%, haze 25%, light transmission 82%; tensile strength 145 MPa, elongation at break 125%; friction coefficient 0.4, surface hardness 2H; UV aging for 500 hours, light transmission and gloss change 10%; matte coating adhesion 5B.

[0109] Comparative Example 9 shows that increasing PEG improves flexibility, but the matte effect is weak, affecting the overall performance of the film.

[0110] In the structure of the high-matte polyester film, the SiO2 particles in the substrate layer A can significantly increase the surface roughness of the substrate, form a microstructure, and enhance the mechanical bonding force between the coating and the substrate. The addition of SiO2 not only improves the scratch resistance of the film, but also optimizes the optical properties of the film, effectively prolonging the service life of the film. In addition, the high thermal stability and structural integrity of SiO2 help to improve the thermal stability of the substrate, ensuring the performance stability of the film in high-temperature environments. By enhancing the interfacial bonding force between the substrate layer A and the surface matte layer B, a better adhesion foundation can be provided for the matte coating C, thereby improving the wear resistance, stability and service life of the coating.

[0111] The polytetrafluoroethylene (PTFE) in the surface matte layer B has excellent slipperiness and low friction performance, which can significantly reduce the surface friction coefficient of the film, reduce interlayer friction and the accumulation of static electricity between film layers, thereby protecting the substrate layer A from mechanical damage and environmental impact, and having an antistatic effect. The addition of PTFE not only improves the overall wear resistance of the matte coating C, making the surface more durable, but also improves the stain resistance of the film, reduces the adhesion of pollutants, and keeps the film surface clean for a long time. In this layer, the addition of polyethylene glycol (PEG) helps to improve the flexibility of the film, reduce the surface tension, and maintain excellent performance of the film in low-temperature or high-humidity environments. PEG can also enhance the water resistance of the coating, reducing the damage of water to the film. The addition of PMMA not only improves the hardness, wear resistance and light scattering properties of the film, but also further enhances the ultraviolet resistance and anti-pollution performance of the film. It works together with other ingredients (such as PTFE, PEG and SiO2, etc.) to make the film have high matte effect while still maintaining excellent mechanical properties and environmental stability.

[0112] The polyurethane acrylate (PUA) in the matte coating C has excellent elasticity and adhesion, and can form a dense protective layer after curing, improving the wear resistance and chemical resistance of the surface matte layer B, and providing additional protection against ultraviolet light and solvent erosion. PUA not only enhances the durability of the surface matte layer B, but also protects the substrate layer A from environmental factors. The silicone silica particles in the coating not only improve the matte effect of the film, but also provide additional scratch resistance, enhancing the surface texture of the film. The silicone silica nanoparticles provide high light scattering capability, which helps to enhance the overall matte effect, while their thermal stability and light stability significantly improve the anti-aging performance of the material, reducing the change in gloss over time. Benzophenone (BP) as an ultraviolet light absorber can effectively absorb and shield ultraviolet light, slow down the damage of ultraviolet light to the material, reduce the aging rate, and prolong the service life of the material. Its addition effectively protects the substrate layer A and the surface matte layer B from changes in physical properties caused by ultraviolet light, thereby ensuring the long-term stability of the film. The addition of polyether siloxane further improves the flexibility and water resistance of the coating, enhancing the adaptability of the film in extreme environments, especially in high humidity environments. The addition of polydimethylsiloxane helps to improve the surface smoothness of the film, enhance the anti-pollution and self-cleaning ability, and avoid affecting the appearance due to dust or stain adhesion on the surface.

[0113] In summary, the high-matte polyester film of the present application has the following advantages due to its unique multi-layer structure design and precise material ratio.(1) Low gloss and matte effect: Through the composite design of nano fillers (such as silica), fluorinated polymers (such as PTFE) and surface nano structure, the surface gloss of the film is effectively reduced, ensuring excellent matte effect, suitable for high demand visual effect requirements.(2) High light transmittance: The A, B double-layer structure design enables the film to maintain high light transmittance, while reducing unnecessary light reflection based on ensuring visual clarity, suitable for precision optical equipment or display applications requiring high light transmittance.(3) Excellent UV resistance, wear resistance, anti-static and matte performance: The film has excellent UV resistance, anti-static, wear resistance and outstanding matte effect, suitable for high-end demand scenarios such as polarizer release film and optical device surface protection, effectively protecting the product from environmental damage and prolonging its service life.(4) Dimensional stability: The combination of multi-layer structure and heat setting process ensures that the film can maintain dimensional stability in complex environments, suitable for extreme environments such as high temperature or high humidity, and can maintain its excellent performance over a long period of use.(5) Enhanced anti-pollution and self-cleaning performance: The addition of polydimethylsiloxane, PTFE and polyether siloxane significantly improves the anti-pollution and self-cleaning ability of the film, keeping the film surface clean and avoiding stain adhesion, especially in complex environments with stronger stain resistance.

[0114] These advantages make high haze polyester film become the ideal choice of high-end material in electronic, optical, automotive and other fields, especially suitable for applications with high requirements on durability, stability, optical effect and environmental resistance.

[0115] Those skilled in the art should understand that, although the utility model is described in the manner of multiple embodiments, not every embodiment contains only one independent technical solution. The description in the specification is only for the sake of clarity, those skilled in the art should understand the specification as a whole and understand the technical solutions involved in each embodiment as being combined into different embodiments to understand the protection scope of the utility model.

[0116] The above is only the specific embodiment of the utility model, not to limit the scope of the utility model. Any equivalent changes, modifications and combinations made by those skilled in the art without departing from the concept and principle of the utility model shall belong to the protection scope of the utility model.

Claims

1. A system for preparing a high-matte polyester film, the high-matte polyester film comprising a substrate layer A, a surface matte layer B, and a matte coating C sprayed onto the outer side of the surface matte layer B; wherein the thickness of the substrate layer A is 30-35 μm; the thickness of the surface matte layer B is 12-15 μm; and the thickness of the matte coating C is 1-5 μm; characterized in that, The preparation system includes a first mixer (100) corresponding to the substrate layer A and a second mixer (200) corresponding to the matte surface layer B. The first mixer (100) and the second mixer (200) share a common PET raw material tank (10). The inlet of the first mixer (100) is connected to the PET raw material tank (10) and a silica raw material tank (11), respectively. The inlet of the second mixer (200) is connected to the PET raw material tank (10), a polytetrafluoroethylene raw material tank (12), a polyethylene glycol raw material tank (13), and a polymethyl methacrylate raw material tank (14), respectively. The outlet of the first mixer (100) is connected to... The outlets of the main extruder (101) and the second mixer (200) are connected to the auxiliary extruder (201). The outlets of the main extruder (101) and the auxiliary extruder (201) are connected to the sheet cooling mechanism (300). The outlet of the sheet cooling mechanism (300) is connected to the longitudinal stretching mechanism (400). The outlet of the longitudinal stretching mechanism (400) is connected to the transverse stretching mechanism (500). Downstream of the transverse stretching mechanism (500) are a spraying mechanism (601) and an ultraviolet irradiation mechanism (602). Downstream of the ultraviolet irradiation mechanism (602) is a heat setting mechanism (701). Downstream of the heat setting mechanism (701) is a winding mechanism (700).

2. The preparation system according to claim 1, characterized in that, The inlet of the spraying mechanism (601) is connected to a matte paint tank (600).

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