A glass temporary protection LED curing paint and a preparation method thereof

Abstract

The present application relates to a kind of glass temporary protection UV coating and its preparation method: it is made of acid anhydride modified polyurethane multifunctional acrylate, polyethylene glycol di(meth)acrylate, acryloyl morpholine, dimethyl acrylamide 1, methyl acrylate phosphate, silane coupling agent, photoinitiator, leveling aid and the like.The radiation curing glass temporary protection coating provided by the present application has the following advantages: simple to use (1-2S is completed curing, forming protection), after being irradiated by certain energy ultraviolet light, the film adhesion is excellent, the coating film physical resistance is good (avoiding scratch, scratch, peeling during transportation, use, processing process), and the like is easily soaked with alkali water in later period and separated.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of temporary protective coating, in particular to a glass temporary protection UV coating with simple preparation, high hardness and easy cleaning characteristics and a preparation method thereof. BACKGROUND

[0002] Under the background of increasing environmental awareness and increasingly stringent environmental regulations, consumers' desire for environmentally friendly products is becoming stronger. UV coatings, with their significant advantage of low volatile organic compound emissions, are showing unlimited market potential, especially in the field of LED light curing, overcoming the shortcomings of short working life, potential mercury pollution, serious heating, and unstable ultraviolet light intensity output of traditional mercury lamp curing. As the primary development direction, it is the trend of the times.

[0003] Glass products are ubiquitous in daily life, such as car glass, home decoration glass, and mobile phone screen protection glass. During their daily processing, they are easily damaged and contaminated. Coating a temporary protective film on their surface is an important protective measure. The existing technology in this field has the problems of difficult film removal, long time consumption, and large labor consumption. Some solvent-based temporary protective coatings contain volatile, toxic and harmful solvents, which pose a threat to the human body and the environment. Therefore, it is an urgent need to develop a temporary protective coating that is easy to remove, efficient and environmentally friendly. Combined with the characteristics of UV radiation curing, the present application provides a preparation method of LED radiation curing coating with good adhesion to glass, high hardness and simple operation, which can be easily removed by soaking in alkaline water after protection. SUMMARY

[0004] The present application aims to overcome the above-mentioned technical defects and provides a LED curing coating with simple preparation, high efficiency, high hardness and easy removal after protection, and a preparation method thereof.

[0005] The technical solution adopted by the present application to solve the technical problems is:

[0006] A glass temporary protection LED curing coating, comprising the following components by weight fraction:

[0007] 50-70 parts of anhydride modified polyurethane multifunctional acrylate;

[0008] 10-30 parts of UV active monomer one;

[0009] 10-25 parts of UV active monomer two;

[0010] 1 part of methacrylate phosphate;

[0011] 1 part of silane coupling agent;

[0012] 3-5 parts of photoinitiator;

[0013] Leveling aid 0.3 parts.

[0014] As a preferred embodiment, the glass temporary protection LED curing coating described above, the anhydride modified polyurethane multifunctional acrylate is a resin with the following structure, n≥0. According to the actual performance required, the actual value of n is preferably 4.

[0015]

[0016] As a preferred embodiment, the preparation method of the anhydride modified polyurethane multifunctional acrylate described in the present application comprises the following steps:

[0017] (1) In the pentaerythritol triacrylate, isophorone diisocyanate (IPDI) is added, dibutyltin dilaurate is used as a catalyst, and p-hydroxyanisole is used as a polymerization inhibitor, and the reaction is carried out at 80-90°C for 2 hours. When the NCO reaches the theoretical value, the first step intermediate product A is prepared;

[0018] (2) The intermediate product A prepared in the first step is cooled to 40-50°C, tetraethylene glycol is added, and dibutyltin dilaurate catalyst is added, and the reaction is carried out at 80-90°C for 2 hours. When the NCO theoretical value is reached, the second step intermediate product B is prepared;

[0019] (3) The intermediate product B prepared in the second step is cooled to 40-50°C, trimellitic anhydride is added, and triphenylphosphine is used as a catalyst, and the reaction is carried out at 110-120°C for 3 hours. When the acid value reaches the theoretical value, the anhydride modified polyurethane multifunctional acrylate is prepared.

[0020] As a preferred embodiment, the glass temporary protection LED curing coating described above, the UV active monomer one is a bifunctional active monomer PEG200DA (polyethylene glycol diacrylate).

[0021] As a preferred embodiment, the glass temporary protection LED curing coating described above, the monomer two is one or a combination of the two of monofunctional active monomers dimethyl acrylamide (DMAA) and acryloyl morpholine (ACMO).

[0022] As a preferred embodiment, the methacrylate phosphate described above is 2-hydroxyethyl methacrylate phosphate. The methacrylic acid phosphate is produced by Changxing Company in Taiwan, China, and the product model is EM39.

[0023] As a preferred embodiment, the photoinitiator described is 2,4,6-trimethylbenzoyl-diphenyl phosphine oxide. It is produced by Tianjin Jiurixincai, and the code is TPO.

[0024] As a preferred solution, the silane coupling agent is 3-methacryloxypropyltrimethoxysilane, produced by Japan Shin-Etsu Company, and the code is KBM-503.

[0025] As a preferred solution, the polyether modified silicone leveling agent mentioned above is the type 333 leveling agent of BYK Company.

[0026] The application provides a preparation method of a glass temporary protection LED curing paint.

[0027] As a more preferred solution, the application provides a preparation method of a UV wear-resistant skin-feeling paint, comprising the following steps:

[0028] (1) first, the UV active monomer one and the active monomer two are put into a dispersion cylinder, 800-1200 revolutions per minute, 30 minutes, dissolved and stirred uniformly;

[0029] (2) the methyl methacrylate phosphate and the silane coupling agent are put into the dispersion cylinder of step 1, and dispersed for another 30 minutes;

[0030] (3) the leveling agent is slowly added, and high-speed dispersion is performed for 20 minutes;

[0031] (4) the anhydride modified polyurethane multifunctional acrylate is put into the dispersion cylinder of step 3, and high-speed dispersion is performed for 60 minutes;

[0032] (5) finally, the mixture obtained in step 4 is vacuum degassed, filtered through a 300-mesh screen, and packaged, so that the glass temporary protection LED curing paint is obtained.

[0033] The application has the following advantages and beneficial effects:

[0034] 1. The glass temporary protection LED curing paint provided by the application has the advantages that the paint can be rapidly cured under LED irradiation, and only 1-2 seconds are needed to form a film, the finished paint does not contain volatile organic solvents, and the paint meets the environmental protection concept.

[0035] 2. The glass temporary protection LED curing paint provided by the application has high hardness, and can protect the glass from being scratched during processing and transportation.

[0036] 3. The temporary protective LED curing coating for glass provided by this invention, due to the introduction of a variety of effective components and their reasonable proportions, forms a film with extremely strong adhesion on the glass surface. It has good protective performance during processing, does not peel off, does not break during cutting, and is resistant to cutting fluid corrosion.

[0037] 4. The temporary protective LED curing coating for glass provided by this invention has the advantage of fast film removal speed after processing, which can be completed in 1 minute. Attached Figure Description

[0038] Figure 1 This is a schematic diagram of the structure of anhydride-modified polyurethane multifunctional acrylate. Detailed Implementation

[0039] The present invention will be further described in detail below through embodiments. These embodiments are only used to illustrate the present invention and do not limit the scope of the present invention.

[0040] 1. The anhydride-modified polyurethane multifunctional acrylate described in the following examples has the following structure:

[0041]

[0042] Anhydride-modified polyurethane multifunctional acrylate is prepared by the following method:

[0043] (1) At room temperature, in a four-necked flask, 1 mole of isophorone diisocyanate (IPDI), 0.2 g of dibutyltin dilaurate as catalyst, and 2 g of p-hydroxyanisole as polymerization inhibitor as substrate, 1 mole of pentaerythritol triacrylate was slowly added dropwise over half an hour. The addition process was exothermic, and the temperature was controlled below 80°C. Then, the reaction was carried out at 80-90°C for 2 hours. When NCO ≤ 8.3%, the first step intermediate product A was obtained.

[0044] (2) Cool the intermediate product A obtained in the first step to 40-50℃, then add 1 mole of tetraethylene glycol dropwise. After the addition is complete, add 0.2 g of dibutyltin dilaurate catalyst and keep warm at 80-90℃ for 2 hours. When NCO ≤ 0.3%, the intermediate product B of the second step is obtained.

[0045] (3) Cool the intermediate product B obtained in the second step to 40-50℃, add 1 mole of trimellitic anhydride, use 3g of triphenylphosphine as catalyst, react at 110-120℃ for 3 hours, keep warm for 1 hour, and when the acid value is ≤125mg KOH / g, the acid anhydride modified polyurethane multifunctional acrylate is obtained.

[0046] 2. Prepare a glass temporary protective LED curing coating according to the raw material ratios in Table 1 below.

[0047] Table 1

[0048]

[0049]

[0050] The above coating of Examples 1-3 and Comparative Examples 1-3 was coated on a mirror glass standard plate (Guangzhou Biao Ge Da BGD2604) at a coating amount of 10 g / m 2 (General film thickness of the obtained paint is about 10 μm), and after roller coating, far infrared leveling was performed for 10 seconds, and irradiation was performed under an LED lamp (395 nm wavelength) under an energy of 1000 mj / cm 2 with oxygen curing.

[0051] After UV curing, the test sample plate was allowed to stabilize for 60 min in a constant temperature and humidity chamber (temperature 21-25°C, humidity 45-55%), and then performance detection was performed on Examples 1-3 and Comparative Examples 1-3 (all results were measured in a constant temperature and humidity laboratory). The performance test method is shown in Table 2.

[0052] Table 2

[0053] Item Index Test method Remark Pencil hardness (Mitsubishi) As required GB / T 6739-1996 Pencil hardness tester (the higher the hardness, the better) Cutting fluid resistance As required Immersion More than 120 minutes of paint film integrity without falling off Adhesion ≤ 1 level GB / T 9268-1998 Cross-cut knife (3M tape) Alkali bubble shedding As required 5% NaOH \ 60°C immersion Less than 1 minute of overall shedding (stopwatch)

[0054] Table 3

[0055]

[0056] The acid anhydride modified polyurethane multifunctional acrylate in the present application can impart strong hardness and scratch resistance to the paint film. Through effective structural design, a reasonable 4-ethoxy structure is built to achieve reasonable hydrophilicity (excessive hydrophilicity is not resistant to cutting fluid, and easy film fading in the later stage is also considered), and a terminal dicarboxylic structure is designed to quickly react in alkaline water, destroy the paint film structure, and easily fade the film. The introduction of PEG200DA (polyethylene glycol diacrylate) long-chain monomers increases the flexibility of the paint film, reduces the shrinkage of UV curing, and increases the adhesion. In addition, the introduction of ethoxylated groups makes it easier to fall off when alkaline water is bubbled. The synergistic addition of monofunctional monomers DMAA and ACMO can improve the LED photopolymerization activity of the overall coating on one hand, and on the other hand, the hydrophilic properties of the two can make it easier to fall off when alkaline water is bubbled. The synergistic addition of methacrylic acid phosphate and 3-methacryloyloxypropyl trimethoxysilane improves the adhesion of the coating on glass, and makes it difficult for the paint film to fall off when cutting. The selected 2,4,6-trimethylbenzoyl-diphenyl phosphine oxide TPO has relatively strong absorption near 395 nm wavelength, is the most representative LED photoinitiator, has high initiation efficiency, and does not yellow. Through comparison, the comprehensive performance of Examples 1-3 of the present application is better than that of Comparative Examples 1-3, and in particular, Example 2 shows the best comprehensive performance.

[0057] The above merely describes the preferred embodiments of the present application, and it should be pointed out that, for those skilled in the art, several improvements and refinements can be made without departing from the principles of the present application, and these improvements and refinements should also be considered as falling within the protection scope of the present application.

Claims

1. A temporary UV protective coating for glass, characterized in that, The ingredients comprise the following parts by weight: 50-70 parts of anhydride-modified polyurethane multifunctional acrylate; 10-30 parts of UV-active monomer; 10-25 parts of UV-active monomer II; 1-3 parts of methacrylate phosphate; 1-3 parts of silane coupling agent; 3-5 parts of photoinitiator; Leveling agent 0.3-1 part; The anhydride-modified polyurethane multifunctional acrylate has the following structure: n＝4； The UV-active monomer is polyethylene glycol di(meth)acrylate; The UV-active monomer 2 is a combination of acryloylmorpholine and dimethylacrylamide.

2. The temporary UV protective coating for glass according to claim 1, characterized in that, It is made from the following parts by weight of raw materials: 50-70 parts of anhydride-modified polyurethane multifunctional acrylate; 10-30 parts of UV-active monomer; 10-25 parts of UV-active monomer II; 1 part of methacrylate phosphate; 1 part of silane coupling agent; 3-5 parts of photoinitiator; 0.3 parts of leveling agent.

3. The temporary protective LED curing coating for glass according to claim 1, characterized in that: The preparation method of the anhydride-modified polyurethane multifunctional acrylate includes the following steps: (1) Isophorone diisocyanate was added to pentaerythritol triacrylate, with dibutyltin dilaurate as catalyst and p-hydroxyanisole as polymerization inhibitor, and the reaction was carried out at 80-90℃. When NCO reached the theoretical value, the first step intermediate product A was obtained. (2) Cool the intermediate product A obtained in the first step to 40-50℃, add tetraethylene glycol, add dibutyltin dilaurate catalyst, and react at 80-90℃. When the theoretical value of NCO is reached, the intermediate product B of the second step is obtained. (3) Cool the intermediate product B obtained in the second step to 40-50℃, add trimellitic anhydride, use triphenylphosphine as a catalyst, react at 110-120℃, keep warm, and when the acid value reaches the theoretical value, the acid anhydride modified polyurethane multifunctional acrylate is obtained.

4. The glass temporary protective LED curing coating according to claim 1, characterized in that: The methacrylate phosphate is 2-hydroxyethyl methacrylate phosphate.

5. The temporary protective LED curing coating for glass according to claim 1, characterized in that: The silane coupling agent is 3-methacryloyloxypropyltrimethoxysilane.

6. The temporary protective LED curing coating for glass according to claim 1, characterized in that: The photoinitiator is 2,4,6-trimethylbenzoyl-diphenylphosphine oxide.

7. The temporary protective LED curing coating for glass according to claim 1, characterized in that: The leveling agent is a polyether-modified organosilicon.

8. The method for preparing the glass temporary protective LED curing coating according to any one of claims 1 to 7, characterized in that: Includes the following steps: According to the formula, UV active monomer one, UV active monomer two, photoinitiator, methacrylate phosphate, silane coupling agent, and leveling agent are added to a high-speed dispersion kettle, stirred at 800-1200 rpm, and then anhydride-modified polyurethane multifunctional acrylate is added. After stirring and dispersing evenly, vacuum degassing is performed to obtain a temporary UV protective coating for glass.

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