Skin-touch wood lacquer as well as preparation, application and use method thereof

Abstract

The invention discloses skin-feeling wood lacquer as well as preparation, application and a use method thereof, and belongs to the technical field of wood coatings. The wood lacquer is prepared from the following components in parts by weight: a polyurethane acrylate prepolymer, an acrylate monomer, hydroxyl modified resin, a first dispersing agent, a second dispersing agent, a photoinitiator, matting powder, a defoaming agent, an anti-yellowing auxiliary agent and a flatting agent, the photoinitiator, the matting powder and the flatting agent are specifically compounded and combined. The wood lacquer is subjected to forward and reverse roller coating construction and is radiated by 254nm ultraviolet light, so that excellent matte gloss and fine skin feeling can be obtained, meanwhile, the wood lacquer has high hardness, excellent flexibility and bending resistance and good yellowing resistance, and the coating requirements of bent parts such as corrugated edges and lock hole edges of wooden doors can be met.

Description

Technical Field

[0001] This invention relates to the field of wood coating technology, specifically to a skin-feel wood coating and its preparation, application and usage methods. Background Technology

[0002] Traditionally, spraying is widely used for coating wooden doors. However, this process suffers from low efficiency, high technical requirements, low paint utilization, and high emissions of volatile organic compounds (VOCs). Roller coating, especially forward and reverse roller coating, offers a highly efficient alternative that significantly improves production efficiency and reduces VOC emissions. However, commonly available UV roller coatings often sacrifice flexibility in pursuit of high hardness, resulting in brittle films that cannot meet the bending requirements of wooden doors at edges such as hinges and keyholes. This can lead to cracking and paint peeling during bending.

[0003] In the prior art, Chinese invention patent application CN106433275A discloses a solvent-free UV roller-coated transparent wood putty, using bisphenol A epoxy acrylate and polyester acrylate oligomers as base materials, compounded with anhydrous transparent powder, talc powder and other fillers, as well as dispersants, photoinitiators and other additives, suitable for a fully sealed process of base coloring and top color correction. However, using only bifunctional oligomers results in insufficient film flexibility, making it unsuitable for bending wooden doors; the photoinitiator's compounding system and wavelength compatibility are not clearly defined, limiting curing efficiency and potentially posing a yellowing risk.

[0004] Therefore, there is an urgent need in this field to develop a UV roller coating wood coating that combines high hardness, excellent flexibility, matte finish, and good resistance to yellowing, and is suitable for rapid curing with a 254nm excimer light source. Summary of the Invention

[0005] The purpose of this invention is to provide a skin-feel wood coating and its preparation, application and use methods, to solve the defects of existing spraying processes and the problems of insufficient flexibility, poor skin feel and poor yellowing resistance of traditional roller-coated UV wood coatings, and to achieve high-quality coating of bent parts such as the edges of wooden doors and keyholes.

[0006] To achieve the above objectives, in a first aspect, the present invention provides a skin-feel wood coating, comprising, by weight, the following components: 55-65 parts of polyurethane acrylate prepolymer, 15-18 parts of acrylate monomers, 10-14 parts of hydroxyl-modified resin, 1-2 parts of dispersant, 2.5-4 parts of photoinitiator, 4-6 parts of matting agent, 0.1-0.3 parts of defoamer, 0.2-0.4 parts of anti-yellowing agent, and 0.5-1 parts of leveling agent; wherein the polyurethane acrylate prepolymer comprises trifunctional aliphatic polyurethane acrylate and difunctional aromatic polyurethane acrylate.

[0007] Preferably, the mass ratio of the trifunctional aliphatic polyurethane acrylate to the difunctional aromatic polyurethane acrylate is 1:(0.8-1.2).

[0008] This invention discovers that by compounding trifunctional aliphatic polyurethane acrylate and difunctional aromatic polyurethane acrylate prepolymers in a 1:(0.8-1.2) ratio, a balance between the "rigidity" and "flexibility" of the coating film is cleverly achieved, resolving the technical contradiction of simultaneously achieving high hardness and high flexibility. The likely reason is that the difunctional aromatic polyurethane acrylate provides long-chain flexibility, which is key to the bending resistance of the coating film; while the trifunctional aliphatic polyurethane acrylate provides a higher crosslinking density, contributing to the hardness and abrasion resistance of the coating film.

[0009] Preferably, the acrylate monomers include one or more of pentaerythritol triacrylate, dipropylene glycol diacrylate, and 1,6-hexanediol diacrylate.

[0010] More preferably, the acrylate monomer is 1,6-hexanediol diacrylate.

[0011] Preferably, the hydroxyl-modified resin is purchased from Changsha Guangxin New Material Technology Co., Ltd., and its brand name is LT-408.

[0012] Preferably, the first dispersant and the second dispersant include one or more of BYK2009, BYK103, BYK164, BYK110, EFKA4010, EFKA4010, and TEGO245.

[0013] More preferably, the first dispersant is BYK103; the second dispersant is BYK2009.

[0014] Preferably, the photoinitiator comprises 2,4,6-trimethylbenzoyldiphenylphosphine oxide and 1-hydroxycyclohexylphenyl ketone.

[0015] More preferably, the mass ratio of 2,4,6-trimethylbenzoyl diphenylphosphine oxide to 1-hydroxycyclohexylphenyl ketone is 1:(25-35).

[0016] Preferably, the matting agent is a compound of at least two organic modified silica matting agents, the compound comprising a matting agent with an average particle size of 3-6 μm and a matting agent with an average particle size of 4-7 μm, wherein the mass ratio of the 3-6 μm matting agent to the 4-7 μm matting agent is 1:(1-2).

[0017] Furthermore, the 3-6μm matting agent is Evonik OK500; the 4-7μm matting agent is Grace R2105.

[0018] This invention employs a dual-particle-size matte powder compounding technology. Fine-particle matte powder is responsible for filling the microstructure of the paint film, providing basic matte finish and contributing to fineness; while coarse-particle matte powder forms a more uniform micro-rough structure on the surface, working together to achieve extremely low matte gloss and optimize skin feel and texture. Its effect is superior to that of single-particle-size matte powder.

[0019] Preferably, the defoamer includes one or more of BYK055, EFKA2022, TEGO920, Defom6500, and Defom2700.

[0020] Preferably, the anti-yellowing additive includes one or more of Tinuvin 1130, Tinuvin 234, Tinuvin 328, Tinuvin 326, Tinuvin 384, Tinuvin 171, Tinuvin 479, Tinuvin 770, Tinuvin 900, Tinuvin 400, Tinuvin 477, Tinuvin 405, Tinuvin 292, and Tinuvin 123.

[0021] More preferably, the yellowing resistance additive is Tinuvin 1130.

[0022] Preferably, the leveling agent comprises modified polysiloxane containing acrylate groups and polyurethane modified acrylate polymer, wherein the mass ratio of the modified polysiloxane containing acrylate groups to the polyurethane modified acrylate polymer is 1:(2-3).

[0023] A second aspect of the present invention provides a method for preparing the above-mentioned skin-feel wood coating, comprising the following steps: (1) Disperse the polyurethane acrylate prepolymer, acrylate monomers and hydroxyl-modified resin at a speed of 400-600 r / min for 5-10 min; (2) Then add the first dispersant, photoinitiator and matting powder in sequence, increase the rotation speed to 600-800 r / min, and disperse for 10-15 min; (3) Finally, add defoamer, anti-yellowing agent, leveling agent and second dispersant in sequence, disperse at 400-600r / min for 5-10min, adjust the viscosity at 25℃ to 1000-1400cps, and obtain wood paint.

[0024] The third aspect of this invention provides an application of skin-feel wood coating in the coating of wooden doors.

[0025] Preferably, the edge applied to the wooden door is the scalloped edge or the keyhole edge.

[0026] The fourth aspect of this invention provides a method for using a skin-feel wood coating, comprising the following steps: (1) Apply the skin-feel wood coating by forward and reverse roller coating method. The coating amount is 40-50g / m², and the leveling time is 30s-60s after coating. (2) Pre-curing is performed using LED-UV lamps; (3) Then use a 254nm excimer lamp for surface curing; (4) Finally, gallium lamp and mercury lamp are used in sequence for lamp curing.

[0027] Beneficial effects: 1. Through the compounding of specific types and proportions of polyurethane acrylate prepolymers, hydroxyl-modified resins, monomers, and additives, the paint film possesses excellent flexibility, hardness, and impact strength, presenting a high-end skin feel. It meets the bending requirements of parts such as the edges of wooden doors and keyholes, has good resistance to yellowing, is not prone to discoloration with long-term use, and has a long service life.

[0028] 2. Based on the 254nm excimer curing system, combined with a specific composite photoinitiator, the curing speed is fast and the molding efficiency is high; through the synergistic compounding of matting powder, a matte skin-feel film is formed, which has a delicate and smooth feel and enhances the texture of wooden door products.

[0029] 3. The wood coating of this invention is specially designed for forward and reverse roller coating processes, which has high construction efficiency, almost no VOC emissions, and significantly improved environmental protection.

[0030] 4. Specifically designed to solve the coating challenges of special bending areas on wooden doors, combined with wood softening technology and forward and reverse roller coating and excimer curing processes, it improves the overall coating quality of wooden doors and has broad market application prospects. Detailed Implementation

[0031] Unless otherwise specified, the experimental methods described in the following embodiments of the present invention are generally performed under conventional conditions or as recommended by the manufacturer. All commonly used chemical reagents used in the embodiments are commercially available products.

[0032] The technical solutions of the present invention will be clearly and completely described below with reference to the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0033] Example 1 One aspect provides a skin-feel wood coating, the raw materials for which, by weight, are: 30 parts of a first polyurethane acrylate, 30 parts of a second polyurethane acrylate, 16.7 parts of acrylate monomers, 12 parts of hydroxyl-modified resin, 1 part of a first dispersant, 1 part of a second dispersant, 3.1 parts of a photoinitiator, 5 parts of matting agent, 0.2 parts of defoamer, 0.3 parts of anti-yellowing agent, and 0.7 parts of leveling agent.

[0034] The first polyurethane acrylate was purchased from Guangdong Lankelu New Materials Co., Ltd., grade: L-6367-8 (3 functionalities).

[0035] The second polyurethane acrylate (2) was purchased from Tianjin Tianhong Technology Co., Ltd., brand name: CX-9340 (2 functionalities).

[0036] The acrylate monomer is 1,6-hexanediol diacrylate, purchased from Jiangsu Sanmu Chemical Co., Ltd.

[0037] The hydroxyl-modified resin was purchased from Changsha Guangxin New Material Technology Co., Ltd., brand name: LT-408.

[0038] The first dispersant is BYK103; the second dispersant is BYK2009.

[0039] The photoinitiator is 2,4,6-trimethylbenzoyldiphenylphosphine oxide and 1-hydroxycyclohexylphenyl ketone in a mass ratio of 0.1:3.

[0040] 2,4,6-Trimethylbenzoyl diphenylphosphine oxide was purchased from Hubei Gurun Technology Co., Ltd., with the brand name GR-TPO; 1-hydroxycyclohexylphenyl ketone was purchased from Hubei Gurun Technology Co., Ltd., with the brand name 184L.

[0041] The matting agent is a mixture of 2 parts OK500 and 3 parts R2105; wherein OK500 was purchased from Evonik Specialty Chemicals (Shanghai) Co., Ltd.; and R2105 was purchased from Grace Chemicals.

[0042] The defoamer was purchased from TEGO, Germany, brand name: TEGO920; The yellowing resistance additive was purchased from BASF (China) Co., Ltd., brand name: Tinuvin 1130.

[0043] The leveling agent is a mixture of 0.2 parts TEGO450 and 0.5 parts EFKA3777, wherein TEGO450 is purchased from TEGO Germany and EFKA3777 is purchased from BASF (China) Co., Ltd.

[0044] On the other hand, a method for preparing a skin-feel wood coating is provided, including the following steps: (1) The polyurethane acrylate prepolymer, acrylate monomers and hydroxyl-modified resin are dispersed sequentially at 400-600 r / min for 5-10 min; (2) Then add the first dispersant, photoinitiator and matting agent in sequence, and disperse at 600-800 r / min for 10-15 min; (3) Finally, add defoamer, anti-yellowing agent, leveling agent and second dispersant, disperse at 400-600r / min for 5-10min, adjust the viscosity at 25℃ to 1000-1400cps, and obtain wood paint.

[0045] A method for applying a skin-feel wood coating includes the following steps: (1) Apply the skin-feel wood coating by forward and reverse roller coating method. The coating amount is 40-50g / m², and the leveling time is 30s-60s after coating. (2) First, LED-UV lamps are used for pre-curing; (3) Then, surface curing is performed using a 254nm excimer lamp with a curing energy of 160 mJ / cm. 2 ; (4) Finally, gallium lamps and mercury lamps are used for curing in sequence, with a curing energy of 340 mJ / cm. 2 .

[0046] Example 2 Compared with Example 1, the first polyurethane acrylate L-6367-8 was replaced with Haohui 92295, which was purchased from Guangdong Haohui New Materials Co., Ltd.

[0047] Example 3 Compared with Example 1, the first polyurethane acrylate L-6367-8 was replaced with Haohui CR92776, which was purchased from Guangdong Haohui New Materials Co., Ltd.

[0048] Example 4 Compared with Example 1, the second polyurethane acrylate CX-9340 was replaced with Fengjin PU5602, which was purchased from Dongguan Fengjin New Materials Co., Ltd.

[0049] Comparative Example 1 Compared with Example 1, the second polyurethane acrylate CX-9340 was replaced with Sanmu SM6202, which was purchased from Jiangsu Sanmu Chemical Co., Ltd.

[0050] Comparative Example 2 Compared with Example 1, the second polyurethane acrylate CX-9340 was replaced with Hengzhiguang 6100D-85, which was purchased from Guangdong Hengzhiguang Environmental Protection New Materials Co., Ltd.

[0051] Comparative Example 3 Compared with Example 1, the second polyurethane acrylate CX-9340 was replaced with Ketian 4252, which was purchased from Nanxiong Ketian Chemical Co., Ltd.

[0052] Performance testing Performance tests were conducted on the products from Examples 1-4. The test standards and results are shown in the table below:

[0053] Test results show that Example 1 has good toughness and excellent resistance to yellowing; Example 2 has poor toughness and cannot be bent; Example 3 has the same toughness as Example 1, but poor resistance to yellowing.

[0054] Comparison examples 1-3 cannot achieve a matte finish.

Claims

1. A wood finish paint, characterized by, By weight parts, including the following components: polyurethane acrylate prepolymer 55-65 parts, acrylate monomer 15-18 parts, hydroxyl modified resin 10-14 parts, first dispersant 1-2 parts, second dispersant 1-2 parts, photoinitiator 2.5-4 parts, flatting powder 4-6 parts, defoaming agent 0.1-0.3 parts, anti-yellowing aid 0.2-0.4 parts, leveling agent 0.5-1 part; The polyurethane acrylate prepolymer comprises a trifunctional aliphatic polyurethane acrylate and a difunctional aromatic polyurethane acrylate.

2. The wood finish of claim 1 wherein, The mass ratio of the trifunctional aliphatic polyurethane acrylate and the difunctional aromatic polyurethane acrylate is 1:0.8-1.

2.

3. The wood finish of claim 1 wherein, The photoinitiator comprises 2,4,6-trimethylbenzoyl diphenyl phosphine oxide and 1-hydroxycyclohexyl phenyl ketone.

4. The wood finish of claim 3 wherein, The mass ratio of the 2,4,6-trimethylbenzoyl diphenyl phosphine oxide and the 1-hydroxycyclohexyl phenyl ketone is 1:25-35.

5. The wood finish of claim 1 wherein, The flatting powder is a compound of at least two kinds of organic modified silica flatting powders, the compound comprises flatting powder with an average particle size of 3-6 μm and flatting powder with an average particle size of 4-7 μm, and the mass ratio of the flatting powder with an average particle size of 3-6 μm to the flatting powder with an average particle size of 4-7 μm is 1:1-2.

6. The wood finish of claim 1 wherein, The leveling agent comprises modified polysiloxane containing acrylate groups and polyurethane modified acrylate polymer, and the mass ratio of the modified polysiloxane containing acrylate groups to the polyurethane modified acrylate polymer is 1:2-3.

7. A process for the preparation of a skin feel wood finish according to any one of claims 1 to 6, characterized in that, The method comprises the following steps: (1) dispersing the polyurethane acrylate prepolymer, the acrylate monomer and the hydroxyl modified resin at 400-600 r / min for 5-10 min; (2) then sequentially adding the first dispersant, the photoinitiator and the flatting powder, and dispersing at 600-800 r / min for 10-15 min; (3) finally sequentially adding the defoaming agent, the anti-yellowing aid, the leveling agent and the second dispersant, and dispersing at 400-600 r / min for 5-10 min, adjusting the viscosity to 1000-1400 cps at 25°C, to obtain the wood paint.

8. Application of the skin-friendly wood paint according to any one of claims 1-6 to wood door painting.

9. Use of the skin-sensitizing wood lacquer according to claim 8 in the painting of wooden doors, characterized in that, The skin-friendly wood paint is applied to the leaf edge or the lock hole edge of the wood door.

10. A method of using the skin feel device paint according to any one of claims 1-6, characterized in that, The method comprises the following steps: (1) applying the skin-friendly wood paint by using the forward and reverse roller coating mode, and the coating amount is 40-50 g / m², and the leveling time is 30-60 s; (2) pre-curing by using the LED-UV lamp; (3) then curing the surface layer by using the 254 nm excimer lamp; (4) finally sequentially curing by using the gallium lamp and the mercury lamp.

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