Excimer UV skin-touch paint and paint film preparation method thereof

Abstract

The invention relates to the technical field of skin-touch coatings, in particular to an excimer UV skin-touch coating which comprises a phase A, wherein the phase A comprises the following components in percentage by mass: 30%-90% of resin, 5%-40% of a monomer, 0.01%-10% of a photoinitiator and 0.01%-10% of an auxiliary agent; the prepared paint film is soft and smooth in surface, low in glossiness, good in wear-resistant effect and good in chemical resistance, the uneven structure formed by the difference of curing of the surface layer and the inner layer of the paint and the effect of microcosmic wrinkles caused by shrinkage of the surface layer achieves the effects that the surface glossiness is low, and the glossiness is lower than 10 degrees when the incident angle is tested to be 60 degrees; and the generated wrinkles are very fine and are naturally generated radians, so that the hand feeling is very smooth, the dynamic friction coefficient of the surface is very low, and the wrinkles on the surface of the coating are caused because the surface curing speed and the bottom curing speed are different, the surface shrinkage is large and the inside shrinkage is small.

Description

Technical Field

[0001] The present invention relates to the technical field of skin-feel coatings, and in particular to an excimer UV skin-feel coating and a method for preparing a coating film thereof. Background Art

[0002] Skin-feel coatings are favored by consumers for their delicate, soft, smooth feel and skin-like effect. At the same time, skin-feel coatings do not contain any toxic substances and will not harm people's health. They are mainly used in the 3C mobile phone back cover field.

[0003] Skin-feel matte paint is generally made by mixing some feel additives or matte powder into the previously used UV high-gloss paint to form the surface bumps to achieve the matte effect. The surface is formed and the touch is changed by changing the particle size and hardness of the matte powder. The surface unevenness is completely determined by the size of the externally added particles. The uniformity of the coating is difficult to control, and the wrinkle structure and feel of the paint film cannot be guaranteed.

[0004] Therefore, in order to solve the above-mentioned problem that the uniformity of the coating cannot be well controlled by changing the particle size and hardness of the matte powder, a quasi-molecular UV skin-feel coating and a method for preparing the coating film thereof can be designed. Summary of the invention

[0005] In order to overcome the problem of poor control of coating uniformity.

[0006] The technical solution of the present invention is: an excimer UV skin-feel coating, comprising a phase A, wherein the phase A comprises the following components in percentage by mass: resin: 30% to 90%, monomer: 5% to 40%, photoinitiator: 0.01% to 10%, and auxiliary agent: 0.01% to 10%;

[0007] The paint film preparation method is as follows:

[0008] Step 1: Apply phase A coating on the substrate and pre-cure with LED with a wavelength of 395nm. The energy required for curing is 1000-4000mJ / cm 2 , light intensity is 500~4000mW / cm 2 , use 172nm, 185nm or 254nm ultraviolet light for curing in nitrogen, or use 254nm ultraviolet light for curing in air;

[0009] Step 2: The coating surface has wrinkles in the thickness range of 1 to 3 μm due to shrinkage caused by curing. The glossiness is tested at an incident angle of 60 degrees. The wrinkles on the surface cause the glossiness of the coating to drop sharply. When the glossiness drops directly from 100 to 1 to 20, the UVC energy required for surface curing is 50 to 400 mJ / cm 2 , light intensity is 5~20mW / cm 2;

[0010] Step 3: Full curing with high pressure mercury lamp, UVA energy is 1000~2000mJ / cm 2 , UVA light intensity is 50~500mW / cm 2 The third curing is carried out. Under the action of the UVC band, the surface 1-3μm of the coating is quickly cured within 10-120s, while the bottom layer has not yet been cured, forming a wrinkled structure to obtain a paint film, and then the middle and bottom of the coating are fully cured by UVA.

[0011] Preferably, the coating further comprises a phase B, which is a diluent, and the mass percentage of the diluent in the coating is 0% to 90%.

[0012] Preferably, the resin is any one or more combinations of modified acrylate resin, polyester acrylate, polyurethane acrylate, epoxy acrylate, silicon-modified acrylate and fluorine-modified acrylate.

[0013] Preferably, the monomer is any one or more combinations of monofunctional monomers, difunctional monomers, trifunctional monomers and multifunctional monomers.

[0014] Preferably, the photoinitiator includes a type I free radical photoinitiator and a type II free radical photoinitiator.

[0015] Preferably, the auxiliary agent includes any one or more combinations of a leveling agent, a defoaming agent and a nucleating agent.

[0016] Preferably, the diluent is any one or more of ethanol, isopropanol, ethyl ester, butyl ester, PM, PMA, MIBK and butanone.

[0017] Preferably, the coating can be applied by roller coating, flow coating or printing.

[0018] The beneficial effects of the present invention are as follows: the prepared paint film has a smooth surface, low gloss, good wear resistance and good chemical resistance. Due to the difference in curing of the surface layer and the inner layer of the coating itself, the surface layer shrinks to create a microscopic wrinkle effect, and the uneven structure formed achieves a low surface gloss, with the gloss tested at an incident angle of 60 degrees being less than 10 degrees. Moreover, the wrinkles generated are very fine and are naturally generated curvatures, so the hand feels very smooth. The dynamic friction coefficient of the surface is very low, with the friction coefficient being less than 0.1. The coating is not formed by adding matte powder or additives, so there is no problem of poor uniformity control. During the curing process of the coating, because the surface curing speed is different from the bottom curing speed, the surface shrinks more and the inside shrinks less, resulting in wrinkles on the coating surface. The obtained paint film has good adhesion to the paint material, high hardness and good chemical resistance. DETAILED DESCRIPTION

[0019] The present invention will be further described below in conjunction with the embodiments.

[0020] Example 1

[0021] The present invention provides an embodiment: an excimer UV skin-feel coating, comprising the following components in percentage by mass:

[0022] Resin (B-241): 51.2%

[0023] Monomer (9EOTMPTA): 15.7%

[0024] Photoinitiator (TPO): 0.4%

[0025] Photoinitiator (MBF): 0.8%

[0026] Leveling agent (AFCONA3777): 0.4%

[0027] Diluent (butyl ester): 31.5%;

[0028] The preparation method of the excimer UV skin-feel paint film comprises the following steps: adjusting the paint to a density of 0.995 with butyl ester and coating it on the acrylic surface of the composite board (PMMA / PC), drying it at room temperature for 1 minute, drying it in an oven at 50 degrees for 1 minute, baking it at high temperature, and then using a 395nm LED lamp with a light intensity of 2200mW / cm 2 , energy 2600mJ / cm 2 Pre-curing, using 254nm UV lamp at 9mW / cm 2 Light intensity, energy 100mJ / cm 2 After surface curing, use 1800mJ / cm 2 Energy UV mercury lamp, light intensity is 240mW / cm 2 , obtaining a coating with a matte surface effect.

[0029] Example 2

[0030] The present invention provides an embodiment: an excimer UV skin-feel coating, comprising the following components in percentage by mass:

[0031] Resin (B-241): 49.6%

[0032] Monomer (9EOTMPTA): 15.3%

[0033] Nucleating agent (OK520): 3.1%

[0034] Photoinitiator (TPO): 0.4%

[0035] Photoinitiator (MBF): 0.8%

[0036] Leveling agent (AFCONA3777): 0.4%

[0037] Diluent (butyl ester): 30.4%;

[0038] The preparation method of the excimer UV skin-feel paint film comprises the following steps: adjusting the paint to a density of 0.995 with butyl ester and coating it on the acrylic surface of the composite board (PMMA / PC), drying it at room temperature for 1 minute, drying it in an oven at 50 degrees for 1 minute, baking it at high temperature, and then using a 395nm LED lamp with a light intensity of 2200mW / cm 2 , energy 2600mJ / cm 2 Pre-curing, using 254nm UV lamp at 9mW / cm 2 Light intensity, energy 100mJ / cm 2 After surface curing, use 1800mJ / cm 2 Energy UV mercury lamp, light intensity is 240mW / cm 2 , obtaining a coating with a matte surface effect.

[0039] Example 3

[0040] The present invention provides an embodiment: an excimer UV skin-feel coating, comprising the following components in percentage by mass:

[0041] Resin (luCure 5326): 50.3%

[0042] Monomer (9EOTMPTA): 15.4%

[0043] Nucleating agent (OK520): 1.6%

[0044] Photoinitiator (TPO): 0.5%

[0045] Photoinitiator (184): 0.8%

[0046] Leveling agent (AFCONA3777): 0.4%

[0047] Diluent (butyl ester): 31.0%;

[0048] The preparation method of the excimer UV skin-feel paint film comprises the following steps: adjusting the paint to a density of 0.995 with butyl ester and coating it on the acrylic surface of the composite board (PMMA / PC), drying it at room temperature for 1 minute, drying it in an oven at 50 degrees for 1 minute, baking it at high temperature, and then using a 395nm LED lamp with a light intensity of 2200mW / cm 2 , energy 2600mJ / cm 2 Pre-curing, using 254nm UV lamp at 9mW / cm 2Light intensity, energy 100mJ / cm 2 After surface curing, use 1800mJ / cm 2 Energy UV mercury lamp, light intensity is 240mW / cm 2 , obtaining a coating with a matte surface effect.

[0049] Example 4

[0050] The present invention provides an embodiment: an excimer UV skin-feel coating, comprising the following components in percentage by mass:

[0051] Resin (luCure 5326): 51.1%

[0052] Monomer (9EOTMPTA): 15.6%

[0053] Nucleating agent (OK520): 0.1%

[0054] Photoinitiator (TPO): 0.4%

[0055] Photoinitiator (184): 0.8%

[0056] Leveling agent (AFCONA3777): 0.4%

[0057] Diluent (butyl ester): 31.4%;

[0058] The preparation method of the excimer UV skin-feel paint film comprises the following steps: adjusting the paint to a density of 0.995 with butyl ester and coating it on the acrylic surface of the composite board (PMMA / PC), drying it at room temperature for 1 minute, drying it in an oven at 50 degrees for 1 minute, baking it at high temperature, and then using a 395nm LED lamp with a light intensity of 2200mW / cm 2 , energy 2600mJ / cm 2 Pre-curing, using 254nm UV lamp at 9mW / cm 2 Light intensity, energy 100mJ / cm 2 After surface curing, use 1800mJ / cm 2 Energy UV mercury lamp, light intensity is 240mW / cm 2 , obtaining a coating with a matte surface effect.

[0059] Example 5

[0060] The present invention provides an embodiment: an excimer UV skin-feel coating, comprising the following components in percentage by mass:

[0061] Resin (luCure5326): 49.8%

[0062] Monomer (9EOTMPTA): 15.3%

[0063] Nucleating agent (OK520): 0.8%

[0064] Photoinitiator (TPO): 0.8%

[0065] Photoinitiator (184): 2.3%

[0066] Leveling agent (AFCONA3777): 0.4%

[0067] Diluent (butyl ester): 30.6%;

[0068] The preparation method of the excimer UV skin-feel paint film comprises the following steps: adjusting the paint to a density of 0.995 with butyl ester and coating it on the acrylic surface of the composite board (PMMA / PC), drying it at room temperature for 1 minute, drying it in an oven at 50 degrees for 1 minute, baking it at high temperature, and then using a 395nm LED lamp with a light intensity of 2200mW / cm 2 , energy 2600mJ / cm 2 Pre-curing, using 254nm UV lamp at 9mW / cm 2 Light intensity, energy 100mJ / cm 2 After surface curing, use 1800mJ / cm 2 Energy UV mercury lamp, light intensity is 240mW / cm 2 , obtaining a coating with a matte surface effect.

[0069] In the present invention, the purpose of high temperature hot air or infrared baking is mainly to volatilize the diluent. Curing can only be carried out after the diluent is volatilized, otherwise it cannot be dried even after the final UV curing. When the diluent is 0%, high temperature baking is not required.

[0070] Comparative Example 1

[0071] The coating includes the following components:

[0072] Resin (6145): 49.6%

[0073] Monomer (9EOTMPTA): 15.3%

[0074] Matt powder (OK500): 3.1%

[0075] Photoinitiator (TPO): 0.4%

[0076] Photoinitiator (184): 0.8%

[0077] Leveling agent (AFCONA3777): 0.4%

[0078] Diluent (butyl ester): 30.4%;

[0079] Preparation of paint film: The coating was adjusted to a density of 0.995 with butyl ester and then coated on the acrylic surface of the composite board (PMMA / PC). It was dried at room temperature for 1 minute, dried in an oven at 80 degrees for 1 minute, and then placed at room temperature for 1 minute. It was then exposed to UV mercury lamp with an energy of 800mJ / cm 2 , obtaining a coating with a matte surface effect.

[0080] Comparative Example 2

[0081] The coating includes the following components:

[0082] Resin (6145): 50.0%

[0083] Monomer (9EOTMPTA): 15.4%

[0084] Matt powder (OK500): 2.3%

[0085] Photoinitiator (TPO): 0.4%

[0086] Photoinitiator (184): 0.8%

[0087] Leveling agent (AFCONA3777): 0.4%

[0088] Diluent (butyl ester): 30.7%;

[0089] Preparation of paint film: The coating was adjusted to a density of 0.995 with butyl ester and then coated on the acrylic surface of the composite board (PMMA / PC). It was dried at room temperature for 1 minute, dried in an oven at 80 degrees for 1 minute, and then placed at room temperature for 1 minute. It was then exposed to UV mercury lamp with an energy of 800mJ / cm 2 , obtaining a coating with a matte surface effect.

[0090] Comparative Example 3

[0091] The coating includes the following components:

[0092] Resin (6145): 50.3%

[0093] Monomer (9EOTMPTA): 15.5%

[0094] Matt powder (OK500): 1.6%

[0095] Photoinitiator (TPO): 0.4%

[0096] Photoinitiator (184): 0.8%

[0097] Leveling agent (AFCONA3777): 0.4%

[0098] Diluent (butyl ester): 31.0%;

[0099] Preparation of paint film: The coating was adjusted to a density of 0.995 with butyl ester and then coated on the acrylic surface of the composite board (PMMA / PC). It was dried at room temperature for 1 minute, dried in an oven at 80 degrees for 1 minute, and then placed at room temperature for 1 minute. It was then exposed to UV mercury lamp with an energy of 800mJ / cm 2 , obtaining a coating with a matte surface effect.

[0100] Comparative Example 4

[0101] The coating includes the following components:

[0102] Resin (luCure5326): 22.9%

[0103] Monomer (9EOTMPTA): 24.1%

[0104] Matt powder (OK500): 4.8%

[0105] Leveling agent (AFCONA3777): 0.6%

[0106] Diluent (butyl ester): 47.6%;

[0107] Preparation of paint film: The coating was adjusted to a density of 0.995 with butyl ester and then coated on the acrylic surface of the composite board (PMMA / PC). It was dried at room temperature for 1 minute, dried in an oven at 80 degrees for 1 minute, and then placed at room temperature for 1 minute. It was then exposed to UV mercury lamp with an energy of 800mJ / cm 2 , obtaining a coating with a matte surface effect.

[0108] Test Example 1

[0109] Examples 1-5 and Comparative Examples 1-4 were tested, and the test contents and methods were as follows:

[0110]

[0111]

[0112] The test results are as follows:

[0113]

[0114]

[0115] Example 6

[0116] The coating in Example 1 was adjusted to a density of 0.995 and then coated on the acrylic surface of the composite board (PMMA / PC), dried at room temperature for 1 minute, dried in an oven at 50 degrees for 1 minute, pre-cured with a 395nm LED light intensity and energy (see Table 1), and then surface cured with a 254nm ultraviolet lamp at a certain light intensity and energy (see Table 1). Then, a third irradiation curing was performed with a UV mercury lamp with different light intensities and energies (see Table 1). The properties of the obtained paint films are shown in Table 2.

[0117] Table 1 is a table of lighting conditions and energy conditions.

[0118]

[0119] Table 1

[0120] Table 2 is the paint film performance table.

[0121]

[0122]

[0123] Table 2

[0124] Example 7

[0125] Comparative Example 1 and Example 1 were cured according to the following aspects to prepare coatings, and the properties were tested and obtained as shown in Table 3.

[0126] 1. The coating in comparative example 1 was adjusted to a density of 0.925 and then coated on the acrylic surface of the composite board (PMMA / PC). The coating was dried at room temperature for 1 minute, dried in an oven at 80 degrees for 1 minute, and then placed at room temperature for 1 minute. The coating was then exposed to a UV mercury lamp with an energy of 800mJ / cm 2 , obtaining a coating A with a matte surface effect;

[0127] 2. The coating in Example 1 was adjusted to a density of 0.925 and then coated on the acrylic surface of the composite board (PMMA / PC). The coating was dried at room temperature for 1 minute, dried in an oven at 80 degrees for 1 minute, and then placed at room temperature for 1 minute. The coating was then exposed to a UV mercury lamp with an energy of 800 mJ / cm 2 , a coating B with a matte surface effect is obtained;

[0128] 3. The coating in comparative example 1 was adjusted to a density of 0.995 and then coated on the acrylic surface of the composite board (PMMA / PC). After drying at room temperature for 1 minute and in an oven at 50 degrees for 1 minute, a 395nm LED lamp with a light intensity of 2200mW / cm 2 , energy 2600mJ / cm 2 Pre-curing, using 254nm UV lamp at 9mW / cm 2 Light intensity, energy 100mJ / cm2 After surface curing, use 1800mJ / cm 2 Energy UV mercury lamp, light intensity is 240mW / cm 2 , obtaining a coating C with a matte surface effect;

[0129] 4. Adjust the coating in implementation 1 to a density of 0.995 and apply it on the acrylic surface of the composite board (PMMA / PC). Dry it at room temperature for 1 minute and in an oven at 50 degrees for 1 minute. First, use a 395nm LED lamp with a light intensity of 2200mW / cm 2 , energy 2600mJ / cm 2 Pre-curing, using 254nm UV lamp at 9mW / cm 2 Light intensity, energy 100mJ / cm 2 After surface curing, use 1800mJ / cm 2 Energy UV mercury lamp, light intensity is 240mW / cm 2 , obtaining a coating D with a matte surface effect.

[0130] Haze luster Roughness Water drop angle Dynamic friction coefficient Boiled 100g A 30 10 0.55 105 0.1 5B B 8 199 0.1 110 0.1 5B C 0.5 92 0.55 105 0.1 5B D 82 5 0.85 119 0.005 5B

[0131] Table 3

[0132] Due to the difference in curing between the surface and inner layers of the coating itself, the shrinkage of the surface creates a microscopic wrinkle effect, and the uneven structure formed achieves a low surface gloss. The glossiness tested at an incident angle of 60 degrees is less than 10 degrees, and the wrinkles produced are very delicate and are naturally generated curvatures, so the feel is very smooth, and the dynamic friction coefficient of the surface is very low, less than 0.1.

[0133] The embodiments of the present invention are described in detail above, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge scope of those skilled in the art without departing from the spirit of the present invention.

Claims

1. Excimer UV skin-feel coating, characterized in that: It comprises a phase A, wherein the phase A comprises the following components in percentage by mass: resin: 30% to 90%, monomer: 5% to 40%, photoinitiator: 0.01% to 10%, and auxiliary agent: 0.01% to 10%; The paint film preparation method is as follows: Step 1: Apply phase A coating on the substrate and pre-cure with LED with a wavelength of 395nm. The energy required for curing is 1000-4000mJ / cm 2 , light intensity is 500~4000mW / cm 2 , use 172nm, 185nm or 254nm ultraviolet light for curing in nitrogen, or use 254nm ultraviolet light for curing in air; Step 2: The coating surface has wrinkles in the thickness range of 1 to 3 μm due to shrinkage caused by curing. The glossiness is tested at an incident angle of 60 degrees. The wrinkles on the surface cause the glossiness of the coating to drop sharply. When the glossiness drops directly from 100 to 1 to 20, the UVC energy required for surface curing is 50 to 400 mJ / cm 2 , light intensity is 5~20mW / cm 2 ; Step 3: Full curing with high pressure mercury lamp, UVA energy is 1000~2000mJ / cm 2 , UVA light intensity is 50~500mW / cm 2 The third curing is carried out. Under the action of the UVC band, the surface 1-3μm of the coating is quickly cured within 10-120s, while the bottom layer has not yet been cured, forming a wrinkled structure to obtain a paint film, and then the middle and bottom of the coating are fully cured by UVA.

2. The excimer UV skin-feel coating according to claim 1, characterized in that: The coating also includes a phase B, which is a diluent, and the mass percentage of the diluent in the coating is 0% to 90%.

3. The excimer UV skin-feel coating according to claim 1, characterized in that: The resin is any one or more combinations of modified acrylate resin, polyester acrylate, polyurethane acrylate, epoxy acrylate, silicon-modified acrylate and fluorine-modified acrylate.

4. The excimer UV skin-feel coating according to claim 1, characterized in that: The monomer is any one or more combinations of monofunctional monomers, difunctional monomers, trifunctional monomers and multifunctional monomers.

5. The excimer UV skin-feel coating according to claim 1, characterized in that: The photoinitiator includes type I free radical photoinitiator and type II free radical photoinitiator.

6. The excimer UV skin-feel coating according to claim 1, characterized in that: The auxiliary agent includes any one or more combinations of leveling agents, defoaming agents and nucleating agents.

7. The excimer UV skin-feel coating according to claim 1, characterized in that: The diluent is any one or more of ethanol, isopropanol, ethyl ester, butyl ester, PM, PMA, MIBK and butanone.

8. The method for preparing the excimer UV skin-feel paint film according to claim 1, characterized in that: The coating can be applied by roller coating, flow coating or printing.

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