Yellowing-resistant high-hardness TPU mobile phone protective film and preparation method thereof

Abstract

The invention discloses an anti-yellowing high-hardness TPU mobile phone protective film and a preparation method thereof, the protective film is prepared from the following raw materials by weight: 100 parts of a TPU material, 2-6 parts of an anti-yellowing agent ESC SA-PQ35, 3-5 parts of an organosilicon polymer, 0.5-2 parts of a fluorine-containing polymer and 1-2 parts of polyethylene wax PE-WAX, the TPU material is a mixture of polycaprolactone type TPU and polycarbonate type TPU according to a mass ratio of 1: 1-3, and the TPU material is a mixture of polycaprolactone type TPU and polycarbonate type TPU according to a mass ratio of 1: 1-3. And the organic silicon polymer is an FT-653 hardening wear-resistant auxiliary agent. The anti-yellowing high-hardness TPU mobile phone protective film has the advantages that the anti-yellowing performance, the hardness and the wear resistance of the protective film are improved through the synergistic interaction among the components, the protective film has better mechanical property and light transmittance, and the large-scale production of the anti-yellowing high-hardness TPU mobile phone protective film product is realized.

Description

Technical Field

[0001] The invention relates to the technical field of TPU materials, and more specifically to a yellowing-resistant high-hardness TPU mobile phone protective film and a preparation method thereof. Background Art

[0002] There are four main types of mobile phone screen protectors: PP, PVC, PET and TPU. PP films are relatively soft and have poor light transmittance. They cannot prevent scratches or abrasion, but can only prevent dust. Due to poor effects, they have been eliminated from the market. PVC screen protectors are relatively soft, easy to stick, and inexpensive. They have slightly better protective effects than PP, but they have poor light transmittance and clarity, and the surface haze will increase after a period of use, affecting the display effect of the mobile phone screen. They are rarely used at present. PET protective film is the mainstream mobile phone protective film in China. It has high light transmittance, no residual glue after tearing it off, and it is not easy to have small bubbles in the middle of the film. However, this kind of film has a high reflectivity, which will cause users to not be able to see the words on the screen clearly. At the same time, it is easy to leave fingerprints and other traces on the surface. If it is used on curved or folding screen mobile phones, it is easy to cause problems such as warping and creases. TPU mobile phone protective film has good wear resistance and scratch resistance. At the same time, products made of this material have no bubbles after application and have good light transmittance. They will not leave any traces after being torn off. They are increasingly attracting the attention and recognition of mobile phone manufacturers and ordinary consumers. However, TPU mobile phone protective films currently still have problems such as insufficient hardness, easy yellowing, and "nail marks", which greatly limit the development of TPU mobile phone films. Summary of the invention

[0003] The purpose of the present invention is to overcome the deficiencies of the above-mentioned prior art and provide a yellowing-resistant high-hardness TPU mobile phone protective film and a preparation method thereof, which improves the yellowing resistance, hardness and wear resistance of the protective film through the synergistic effect between components, and has good mechanical properties and light transmittance, thereby realizing the large-scale production of yellowing-resistant high-hardness TPU mobile phone protective film products.

[0004] In order to achieve the above object, the present invention adopts the following technical solution:

[0005] A yellowing-resistant high-hardness TPU mobile phone protective film is made of the following raw materials in parts by mass: 100 parts of TPU material, 3.3 parts of anti-yellowing agent ESC SA-PQ35, 3.5 parts of FT-653 hardening and wear-resistant additive, 0.8 parts of fluorine-containing polymer and 1.6 parts of polyethylene wax PE-WAX, wherein the TPU material is a mixture of polycaprolactone TPU and polycarbonate TPU in a mass ratio of 1:1.7.

[0006] Furthermore, the fluorine-containing polymer is at least one of polytetrafluoroethylene, ethylene-tetrafluoroethylene copolymer, perfluoroalkoxy resin, and ethylene-chlorotrifluoroethylene copolymer.

[0007] Furthermore, the protective film is made of the following raw materials in parts by weight: 100 parts of TPU material, 2-6 parts of anti-yellowing agent ESCSA-PQ35, 3-5 parts of silicone polymer, 0.5-2 parts of fluorine-containing polymer and 1-2 parts of polyethylene wax PE-WAX, the TPU material is a mixture of polycaprolactone TPU and polycarbonate TPU in a mass ratio of 1:1-3, and the silicone polymer is FT-653 hardening and wear-resistant additive.

[0008] Furthermore, it is made of the following raw materials in parts by mass: 100 parts of TPU material, 3.3 parts of anti-yellowing agent ESC SA-PQ35, 5.1 parts of FT-653 hardening and wear-resistant additive, 1.5 parts of fluorine-containing polymer and 1 part of polyethylene wax PE-WAX. The TPU material is a mixture of polycaprolactone TPU and polycarbonate TPU in a mass ratio of 1:1.7.

[0009] Furthermore, the protective film has a thickness of 0.1-0.5 mm.

[0010] A method for preparing a yellowing-resistant high-hardness TPU mobile phone protective film comprises the following steps:

[0011] (1) Mixing the TPU material with the silicone polymer, and then adding the anti-yellowing agent ESC SA-PQ35, the fluorine-containing polymer, and the polyethylene wax PE-WAX and continuing to mix evenly to obtain a premix;

[0012] (2) The premix is ​​fed into a screw extruder for melt extrusion, and then subjected to film casting, stretching, heat treatment, and cutting to obtain a yellowing-resistant and high-hardness TPU mobile phone protective film.

[0013] Furthermore, in step (1), the mixing temperature of the entire mixing process is 40-50°C.

[0014] Furthermore, in step (2), the feeding section temperature of the screw extruder is 110-130°C, the mixing section temperature is 145-175°C, the extrusion section temperature is 175-185°C, and the die head temperature is 155-160°C.

[0015] The beneficial effects of the present invention are:

[0016] Polycaprolactone TPU and polycarbonate TPU are compounded and blended, and modified with anti-yellowing agent ESC SA-PQ35, FT-653 hardening and wear-resistant additives, and fluorinated polymers. The yellowing resistance of the TPU protective film is improved by adding an anti-yellowing agent, and the hardening and wear-resistant agent is added to improve the hardness and wear resistance of the product. The compounding of polycaprolactone TPU, polycarbonate TPU, anti-yellowing agent ESC SA-PQ35, and FT-653 hardening and wear-resistant additives can play a synergistic role, greatly improving the yellowing resistance of the product, thereby realizing the large-scale production of yellowing-resistant and high-hardness TPU mobile phone protective film products. DETAILED DESCRIPTION

[0017] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0018] The method for preparing the yellowing-resistant high-hardness TPU mobile phone protective film of the present invention comprises the following steps:

[0019] (1) preparing the following raw materials in parts by weight: 100 parts of TPU material, 2-6 parts of anti-yellowing agent ESC SA-PQ35, 3-5 parts of silicone polymer (preferably FT-653 hardening and wear-resistant additive, purchased from Jinan Hongtu New Materials Co., Ltd.), 0.5-2 parts of fluorine-containing polymer (preferably at least one of polytetrafluoroethylene, ethylene-tetrafluoroethylene copolymer, perfluoroalkoxy resin, ethylene-chlorotrifluoroethylene copolymer) and 1-2 parts of polyethylene wax PE-WAX, wherein the TPU material is a mixture of polycaprolactone TPU (preferably Pearbond DIPP 119 polycaprolactone TPU purchased from Lubrizol or A95K4977 polycaprolactone TPU purchased from Huntsman) and polycarbonate TPU (preferably A95BK4922 polycarbonate TPU purchased from Huntsman or Bayer TPU786E polycarbonate TPU) in a mass ratio of 1:1-3;

[0020] (2) at 40-50° C., the TPU material and the silicone polymer are mixed, and then the anti-yellowing agent ESC SA-PQ35, the fluorine-containing polymer, and the polyethylene wax PE-WAX are added and mixed evenly to obtain a premix;

[0021] (3) The premix is ​​fed into a screw extruder for melt extrusion (the feeding section temperature of the screw extruder is 110-130° C., the mixing section temperature is 145-175° C., the extrusion section temperature is 175-185° C., and the die head temperature is 155-160° C.), and after cast film, stretching, heat treatment, and cutting, a yellowing-resistant high-hardness TPU mobile phone protective film with a thickness of 0.1-0.5 mm is obtained.

[0022] Example 1

[0023] (1) Prepare the following raw materials in parts by weight: 100 parts of TPU material (mixed by Lubrizol Pearbond DIPP 119 polycaprolactone TPU and Huntsman A95BK4922 polycarbonate TPU in a mass ratio of 1:1.7), 3.3 parts of anti-yellowing agent ESCSA-PQ35, 3.5 parts of FT-653 hardening and wear-resistant additive, 0.8 parts of polytetrafluoroethylene and 1.6 parts of polyethylene wax PE-WAX;

[0024] (2) At 40° C., the TPU material was mixed with the FT-653 hardening and wear-resistant additive, and then the anti-yellowing agent ESC SA-PQ35, polytetrafluoroethylene, and polyethylene wax PE-WAX were added and continued to mix evenly to obtain a premix;

[0025] (3) The premix is ​​fed into a screw extruder for melt extrusion (the feeding section temperature of the screw extruder is 120°C, the mixing section temperature is 170°C, the extrusion section temperature is 170°C, and the die head temperature is 160°C), and after cast film, stretching, heat treatment, and cutting, a yellowing-resistant and high-hardness TPU mobile phone protective film with a thickness of 0.1 mm is obtained.

[0026] Comparative Example 1

[0027] A TPU mobile phone protective film was prepared according to the method of Example 1, but the TPU materials were all Lubrizol Pearbond DIPP 119 polycaprolactone TPU.

[0028] Comparative Example 2

[0029] The TPU mobile phone protective film was prepared according to the method of Example 1, but the TPU material was all Huntsman's A95BK4922 polycarbonate TPU.

[0030] Comparative Example 3

[0031] A TPU mobile phone protective film was prepared according to the method of Example 1, but without adding the anti-yellowing agent ESC SA-PQ35.

[0032] Comparative Example 4

[0033] A TPU mobile phone protective film was prepared according to the method of Example 1, except that the anti-yellowing agent ESC SA-PQ35 was replaced by titanium dioxide.

[0034] Comparative Example 5

[0035] The TPU mobile phone protective film was prepared according to the method of Example 1, but without adding FT-653 hardening and wear-resistant additive.

[0036] Comparative Example 6

[0037] The TPU mobile phone protective film was prepared according to the method of Example 1, except that the FT-653 hardening and wear-resistant additive was replaced with polyethylene wax PE-WAX.

[0038] The performance tests of the TPU mobile phone protective films prepared in Example 1 and Comparative Examples 1 to 6 were respectively carried out (the yellowing test was based on the "GB / T16422.2-2022 Plastic Laboratory Light Source Exposure Test Method", and the TPU protective film was cut into 3cm*3cm samples and placed in a xenon arc lamp exposure light aging test box for 2000 hours to test the yellowness index of the sample), and the results are shown in Table 1.

[0039] Table 1

[0040]

[0041] The above is only a preferred embodiment of the present invention, and the protection scope of the present invention is not limited to the above embodiments. All technical solutions under the concept of the present invention belong to the protection scope of the present invention. It should be pointed out that for ordinary technicians in this technical field, some improvements and modifications without departing from the principle of the present invention should also be regarded as the protection scope of the present invention.

Claims

1. A yellowing-resistant high-hardness TPU mobile phone protective film, characterized in that: The protective film is made of the following raw materials in parts by weight: 100 parts of TPU material, 2-6 parts of anti-yellowing agent ESC SA-PQ35, 3-5 parts of silicone polymer, 0.5-2 parts of fluorine-containing polymer and 1-2 parts of polyethylene wax PE-WAX. The TPU material is a mixture of polycaprolactone TPU and polycarbonate TPU in a mass ratio of 1:1-3, and the silicone polymer is FT-653 hardening and wear-resistant additive.

2. According to claim 1, a yellowing-resistant high-hardness TPU mobile phone protective film is characterized in that: The fluorine-containing polymer is at least one of polytetrafluoroethylene, ethylene-tetrafluoroethylene copolymer, perfluoroalkoxy resin, and ethylene-chlorotrifluoroethylene copolymer.

3. According to claim 1, a yellowing-resistant high-hardness TPU mobile phone protective film is characterized in that: It is made of the following raw materials in parts by mass: 100 parts of TPU material, 3.3 parts of anti-yellowing agent ESC SA-PQ35, 3.5 parts of FT-653 hardening and wear-resistant additive, 0.8 parts of fluorine-containing polymer and 1.6 parts of polyethylene wax PE-WAX. The TPU material is a mixture of polycaprolactone TPU and polycarbonate TPU in a mass ratio of 1:1.

7.

4. The yellowing-resistant high-hardness TPU mobile phone protective film according to claim 1, characterized in that: The thickness of the protective film is 0.1-0.5mm.

5. A method for preparing the yellowing-resistant high-hardness TPU mobile phone protective film according to any one of claims 1 to 4, characterized in that: The following steps are involved: (1) Mixing the TPU material with the silicone polymer, and then adding the anti-yellowing agent ESC SA-PQ35, the fluorine-containing polymer, and the polyethylene wax PE-WAX and continuing to mix evenly to obtain a premix; (2) The premix is ​​fed into a screw extruder for melt extrusion, and then subjected to film casting, stretching, heat treatment, and cutting to obtain a yellowing-resistant and high-hardness TPU mobile phone protective film.

6. The method for preparing a yellowing-resistant high-hardness TPU mobile phone protective film according to claim 5, characterized in that: In step (1), the mixing temperature of the entire mixing process is 40-50°C.

7. The method for preparing a yellowing-resistant high-hardness TPU mobile phone protective film according to claim 5, characterized in that: In step (2), the feeding section temperature of the screw extruder is 110-130°C, the mixing section temperature is 145-175°C, the extrusion section temperature is 175-185°C, and the die head temperature is 155-160°C.

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