A method for processing a combination of a beibei paint and a piano paint

Abstract

The application discloses a kind of beibei lacquer and piano lacquer composite processing method, belong to plate coating process technical field.For solving the problem that small defect of bottom lacquer surface is easily amplified by beibei lacquer and piano lacquer in existing plate coating process technology, the application fills the plate defect with batch ash polishing process;Relies on double-layer intermediate lacquer to cover fine trace;Standardized paint preparation standardizes construction process;Segmented maintenance releases lacquer film stress, gradient grinding removes sand mark particles.The application obtains mirror surface effect of considering three-dimensional pearl and clean high-brightness piano lacquer by multilayer protective system, layer by layer blocks defect exposure, improves lacquer film adhesion and lacquer film durability, and is suitable for UV furniture door plate, cabinet plate coating.

Description

Technical Field

[0001] This invention belongs to the field of sheet coating technology, specifically relating to a composite processing method of mother-of-pearl lacquer and piano lacquer. Background Technology

[0002] UV-coated sheets use fiberboard and MDF as base materials, offering advantages such as lightweight and resistance to deformation. Mother-of-pearl paint contains mica pearlescent powder, high-transparency resin, and functional additives, resulting in a three-dimensional gloss and pearlescent texture after curing. Currently, the application process for mother-of-pearl paint on UV-coated sheets largely relies on the experience of the operators. Because mother-of-pearl paint is extremely sensitive to the smoothness of the substrate, the fineness of the paint surface, and the curing environment, traditional application methods can easily damage the optical structure of the mica powder and the film-forming stability of the resin, affecting the product quality of the mother-of-pearl paint sheets.

[0003] Because mother-of-pearl paint is a high-transparency artistic paint, even minor defects in the underlying paint layer are easily visible through the paint layer, directly destroying the overall three-dimensional pearlescent and uniform refractive effect of the mother-of-pearl paint. The transparent effect of piano lacquer mirror varnish further magnifies these minor defects. In traditional processes, the application of each step is often arbitrary. During substrate preparation, defects such as holes, unevenness, and burrs remain, leading to uneven paint adhesion and subsequent peeling and delamination. Furthermore, the mixing ratio of mother-of-pearl paint and the choice of thinner will affect the cured effect. The precise ratio of mother-of-pearl color paint to the main agent directly determines the film thickness, pearlescent concentration, and degree of cross-linking and curing. An excessively high ratio of color paint to main agent will result in excessive pearlescent concentration, causing accumulation and whitening; an excessively low ratio will result in a dull finish. Different types of thinners have significant differences in solubility, evaporation rate, and polarity. Using an unsuitable thinner will not only fail to aid in paint leveling but will also damage the structure of the pearlescent powder and the resin film-forming system within the mother-of-pearl paint.

[0004] Since both mother-of-pearl lacquer and piano lacquer are thick-film high-gloss lacquer, the internal stress of the multi-layered film is large. Without a special transition topcoat to buffer the stress, the interface between the mother-of-pearl lacquer and the surface piano lacquer is weak. Insufficient maintenance or insufficient cross-linking of the lacquer layers can lead to easy peeling and cracking of the lacquer surface.

[0005] Patent CN105667190B discloses a method for producing matte decorative panels. The process involves sequentially sanding the raw blank, repairing the surface of the raw blank, sanding the repaired areas again, applying a primer to form a colored layer and sanding it again, and then applying a topcoat. A matte film is then applied over the topcoat using a laminating machine, cured, and finally removed to obtain the matte paint layer. Products produced using this method have a good surface finish and fewer impurities; however, the matte texture obtained relies on the transfer and replication of the matte film carrier, and the surface texture and matte effect are limited by the specifications of the matte film itself, only achieving a standard matte finish.

[0006] In summary, to address the issue that minor defects in the base coat of existing sheet metal coating processes are easily amplified by both mother-of-pearl lacquer and piano lacquer, a composite processing method combining mother-of-pearl lacquer and piano lacquer is proposed. Summary of the Invention

[0007] The purpose of this invention is to provide a composite processing method for mother-of-pearl lacquer and piano lacquer to solve the problems mentioned in the background art.

[0008] The above-mentioned technical objective of the present invention is achieved through the following technical solution: a method for composite processing of mother-of-pearl lacquer and piano lacquer, characterized by comprising the following steps: S1: Cut the UV board into pieces, apply putty to the surface of the processed UV board before painting, and then sand the entire board after the putty is applied. S2: Apply primer to the treated UV board surface, sand it after the primer has fully cured, apply mixed oil topcoat to the sanded primer surface, and sand it again after the mixed oil topcoat has cured. S3: Mix the mother-of-pearl color paint and mother-of-pearl paint main agent evenly at a mass ratio of 1:0.5 to obtain the mother-of-pearl paint mixture; spray the thinner onto the paint surface simultaneously during the coating process, apply the mother-of-pearl paint topcoat, and let the UV board coated with the mother-of-pearl paint topcoat stand and cure. S4: After the UV board has been left to stand for 4 days, apply two coats of piano lacquer evenly and let it stand for curing for more than 7 days. Then, use 320-grit sandpaper to wet grind the edges and corners of the workpiece. Grind the irregular surfaces of the workpiece uniformly, and finely grind the dead corners, small steps, and gaps. Finally, grind the UY board as a whole, polish it, and perform appearance quality inspection to obtain the finished product.

[0009] Through material preparation, puttying, and overall sanding, imperfections are filled to ensure a smooth base. Two coats of primer and topcoat are applied, followed by two sanding cycles, creating a double-layered intermediate paint surface to provide a smooth support base for the mother-of-pearl lacquer. The mixing ratio of the mother-of-pearl lacquer is controlled to stabilize the pearlescent powder content. During the coating process, a thinner is sprayed onto the paint surface simultaneously to appropriately reduce the viscosity of the surface film and improve the smoothness of the mother-of-pearl lacquer. Static curing allows the resin to cross-link and form a film. Post-treatment is performed to eliminate sand marks and particles on the cured paint surface, resulting in a pearlescent finish from the mother-of-pearl lacquer. Both mother-of-pearl lacquer and piano lacquer are thick-film, high-gloss systems; multiple layers can cause significant internal stress. By first completing the cross-linking of the mother-of-pearl lacquer, then applying two layers of piano lacquer to form a film, combined with long-term constant temperature and humidity curing, the internal stress of the composite paint layer can be released.

[0010] Furthermore, in S1, the puttying treatment uses water-based wood putty with a putty thickness of 0.2~0.5mm.

[0011] Furthermore, the overall sanding is done using 240-320 grit sandpaper.

[0012] Furthermore, in S2, the primer base material is selected as polyurethane sealing primer, and the mixed oil topcoat is selected as solid color mixed oil topcoat.

[0013] Polyurethane sealing primer can seal the pores on the surface of UV-cured boards, prevent the precipitation of small molecules inside the boards, and improve interlayer adhesion; solid color mixed oil topcoat forms a dense and uniform film, which can not only cover up minor imperfections left by the primer, but also build a stress buffer intermediate film between the polyurethane sealing primer and the mother-of-pearl paint, reducing the risk of stress concentration, peeling and cracking between multiple paint layers.

[0014] Furthermore, in S2, the primer is dry-sanded with 320-grit sandpaper after it has fully cured; the mixed oil topcoat is sanded with 400-600-grit sandpaper after it has cured.

[0015] Furthermore, in S3, the mother-of-pearl paint and the mother-of-pearl paint main agent are mixed and stirred continuously for 3-5 minutes.

[0016] Furthermore, in S3, the diluent is selected from any one of propylene ester diluents, ketone reactive diluents, and butyl acetate.

[0017] Furthermore, in S3 and S4, the temperature during the static curing and maintenance stages is 18℃~28℃, and the relative humidity is 40%~70%.

[0018] Furthermore, in S4, the irregular surfaces of the workpiece are uniformly ground to 800 grit, and the dead corners, small steps, and gaps of the workpiece are finely ground to 1200-1500 grit; the fine sand is used for overall grinding to 1000 grit.

[0019] The beneficial effects of this invention are: 1. This invention addresses the issue of substrate defects being filled in through puttying and sanding during pretreatment; a two-layer intermediate system is constructed using a polyurethane sealing primer and a solid-color mixed oil topcoat; standardized paint mixing and application procedures are implemented; segmented curing releases film stress; and gradient grinding removes sanding marks and particles. Through multi-layer protection, a mirror-like effect that combines a three-dimensional pearlescent finish with a clean, high-gloss piano lacquer is achieved, effectively solving the problem in existing processes where substrate defects are easily amplified by both mother-of-pearl and piano lacquer.

[0020] 2. This invention uses a fixed ratio, standardized stirring, and diluent to ensure uniform dispersion of mica pearlescent powder in the mother-of-pearl paint, avoiding defects such as pearlescent accumulation, pinholes, and sagging caused by uneven manual mixing. After the mother-of-pearl paint has cured for 4 days, two coats of piano varnish are sprayed and the entire paint is cured for more than 7 days using layered constant temperature and humidity long-term curing, allowing the multi-layer high-gloss paint to cross-link step by step and fully release stress.

[0021] 3. The coating of this invention uses polyurethane sealing primer, solid color mixed oil topcoat, mother-of-pearl varnish, and piano varnish. The polyurethane sealing primer penetrates into the pores of the UV board to form a dense barrier layer, locking in free small molecules inside the board. The solid color mixed oil topcoat covers minor marks by relying on the high coverage of solid color paint. The mother-of-pearl varnish has excellent compatibility with the upper and lower paint layers with the matching thinner. The piano varnish creates a high-gloss effect of a high-pass lens surface, highlighting the three-dimensional pearlescent texture of the lower mother-of-pearl varnish, and filling in minor grinding marks to unify the flatness of the board surface.

[0022] Appendix Explanation Table 1 is a performance comparison table of each sample in the embodiments of the present invention. Detailed Implementation

[0023] The present invention will be further described in detail below with reference to the appendix.

[0024] This specific embodiment is merely an explanation of the present invention and is not intended to limit the invention. After reading this specification, those skilled in the art can make modifications to this embodiment without contributing any inventive step, but such modifications are protected by patent law as long as they are within the scope of the claims of the present invention.

[0025] Example 1 The UV board is cut into pieces and then coated with water-based wood putty. The putty thickness is 0.2mm. After the putty is applied, it is sanded with 240-grit sandpaper.

[0026] Apply a polyurethane sealing primer to the treated UV board surface. After the polyurethane sealing primer has fully cured, dry sand it with 320-grit sandpaper. Apply a solid color mixed oil topcoat to the sanded polyurethane sealing primer surface. After the mixed oil topcoat has cured, sand it again with 400-grit sandpaper.

[0027] Mix the mother-of-pearl color paint and mother-of-pearl paint main agent at a mass ratio of 1:0.5 until uniform. Stir continuously for 3 minutes after mixing to obtain the mother-of-pearl paint mixture. During the coating process, spray acrylic thinner onto the paint surface simultaneously to apply the mother-of-pearl paint topcoat. Control the temperature at 18℃ and the relative humidity at 40%. Allow the UV-coated boards to cure statically.

[0028] After the UV board has been left to stand for 4 days, two coats of piano lacquer are applied evenly. The temperature is controlled at 18℃ and the relative humidity at 40%. The board is left to cure for more than 7 days. The edges and corners of the workpiece are then wet-ground with 5650-grit 320-grit sandpaper. The irregular surfaces of the workpiece are ground to 800 grit. The dead corners, small steps, and gaps are finely ground to 1200 grit. Finally, the entire board is sanded to 1000 grit with 8700-grit sandpaper. Polishing and appearance inspection are then performed to obtain the finished product.

[0029] Example 2 The UV board is cut into pieces and then water-based wood putty is used to apply putty to the surface of the UV board. The putty thickness is 0.4mm. After the putty is applied, 280-grit sandpaper is used to sand the entire surface. Apply a polyurethane sealing primer to the treated UV board surface. After the polyurethane sealing primer has fully cured, dry sand it with 320-grit sandpaper. Apply a solid color mixed oil topcoat to the sanded polyurethane sealing primer surface. After the mixed oil topcoat has cured, sand it again with 500-grit sandpaper.

[0030] Mix the mother-of-pearl color paint and mother-of-pearl paint main agent at a mass ratio of 1:0.5 until uniform. Stir continuously for 4 minutes after mixing to obtain the mother-of-pearl paint mixture. During the coating process, spray the paint surface with a ketone-based reactive thinner simultaneously and apply the mother-of-pearl paint topcoat. Control the temperature at 24℃ and the relative humidity at 55%. Allow the UV-coated boards to cure statically.

[0031] After the UV-cured sheets have been left to stand for 4 days, two coats of piano lacquer are applied evenly. The temperature is controlled at 24℃ and the relative humidity at 55%. The sheets are left to cure for at least 7 days. The edges and corners of the workpiece are then wet-ground with 5650-grit 320-grit sandpaper. The irregular surfaces of the workpiece are then uniformly ground to 800 grit. The corners, small steps, and gaps are finely ground to 1400 grit. Finally, the entire surface is sanded to 1000 grit with 8700-grit sandpaper. Polishing and visual inspection are then performed to obtain the finished product.

[0032] Example 3 The UV board is cut and processed, and water-based wood putty is used to apply putty to the surface of the processed UV board. The putty thickness is 0.5mm. After the putty is applied, 320-grit sandpaper is used for overall sanding. Apply a polyurethane sealing primer to the treated UV board surface. After the polyurethane sealing primer has fully cured, dry sand it with 320-grit sandpaper. Apply a solid color mixed oil topcoat to the sanded polyurethane sealing primer surface. After the mixed oil topcoat has cured, sand it again with 600-grit sandpaper.

[0033] Mix the mother-of-pearl color paint and mother-of-pearl paint main agent at a mass ratio of 1:0.5 until uniform. Stir continuously for 5 minutes after mixing to obtain the mother-of-pearl paint mixture. During the coating process, spray butyl acetate onto the paint surface simultaneously to apply the mother-of-pearl paint topcoat. Control the temperature at 28℃ and the relative humidity at 70%. Allow the UV-coated board with the mother-of-pearl paint topcoat to cure statically.

[0034] After the UV-cured sheets have been left to stand for 4 days, two coats of piano lacquer are applied evenly. The temperature is controlled at 28℃ and the relative humidity at 70%. The sheets are left to cure for at least 7 days. The edges and corners of the workpiece are then wet-ground with 5650-grit 320-grit sandpaper. The irregular surfaces of the workpiece are then uniformly ground to 800 grit. The corners, small steps, and gaps are finely ground to 1500 grit. Finally, the entire surface is sanded to 1000 grit with 8700-grit sandpaper. Polishing and visual inspection are then performed to obtain the finished product.

[0035] Comparative Example 1 UV boards of the same specifications as in Example 1 were selected for cutting and processing, and 180-grit sandpaper was used for overall sanding. Apply a polyurethane sealing primer to the treated UV board surface, and dry sand it with 320-grit sandpaper 24 hours after the polyurethane sealing primer has fully cured.

[0036] Mix the mother-of-pearl color paint and mother-of-pearl paint main agent at a mass ratio of 1:0.5 until homogeneous. Stir continuously for 5 minutes after mixing to obtain the mother-of-pearl paint mixture. During the coating process, spray the paint surface with a ketone-based reactive thinner simultaneously and apply the mother-of-pearl paint topcoat. Control the temperature at 24℃ and the relative humidity at 55%. Allow the UV-coated boards to cure statically.

[0037] After the UV-cured sheets have been left to stand for 4 days, two coats of piano lacquer are applied evenly. The temperature is controlled at 24℃ and the relative humidity at 55%. The sheets are left to cure for at least 7 days. The edges and corners of the workpiece are then wet-ground with 5650-grit 320-grit sandpaper. The irregular surfaces of the workpiece are then uniformly ground to 800 grit. The corners, small steps, and gaps are finely ground to 1400 grit. Finally, the entire surface is sanded to 1000 grit with 8700-grit sandpaper. Polishing and visual inspection are then performed to obtain the finished product.

[0038] Comparative Example 2 The UV board is cut into pieces and then water-based wood putty is used to apply putty to the surface of the UV board. The putty thickness is 0.4mm. After the putty is applied, 280-grit sandpaper is used to sand the entire surface. Apply a polyurethane sealing primer to the treated UV board surface. After the polyurethane sealing primer has fully cured, dry sand it with 320-grit sandpaper. Apply a solid color mixed oil topcoat to the sanded polyurethane sealing primer surface. After the mixed oil topcoat has cured, sand it again with 500-grit sandpaper.

[0039] Mix the mother-of-pearl color paint and mother-of-pearl paint main agent evenly at a mass ratio of 1:0.2~1:1 to obtain the mother-of-pearl paint mixture; during the coating process, spray the paint surface with strong banana oil simultaneously to apply the mother-of-pearl paint topcoat, and control the temperature at 24℃ and the relative humidity at 55%.

[0040] After the UV-coated boards with mother-of-pearl lacquer topcoat are left to stand for 1 day, they are sprayed with piano varnish, naturally stacked and cured at room temperature for 3 days, and then the entire board is dry sanded with 400-grit sandpaper.

[0041] The appearance was tested according to the national standard GB / T 9761-2008 "Visual colorimetric comparison of paints and varnishes".

[0042] The surface roughness of the plate is tested in accordance with the national standard GB / T 1031-2009 "Geometric Technical Specifications for Products - Surface Roughness".

[0043] The color difference of pearlescent coatings in the same batch was tested according to the national standard GB / T 11186-1989 "Method for measuring the color of coatings".

[0044] The adhesion peeling area was tested according to the national standard GB / T 9286-1998 "Cross-cut test of paint and varnish film".

[0045] The gloss decay rate was tested according to the national standard GB / T 4893.6-2013 "Tests on the physical and chemical properties of paint films on furniture surfaces - Part 6: Gloss determination method". Table 1 As shown in Table 1, the finished products obtained in Examples 1-3 have no pitted spots, sand marks, or transparent bottoms, and have a pure mirror finish; the surface roughness Ra is ≤0.4μm, and the piano lacquer mirror effect after polishing is clean and transparent; the color difference of pearlescent lacquer in the same batch is controlled within 1.2, and the three-dimensional layers are uniform; the area of ​​detachment of 2mm adhesion in the cross-cut adhesion test is <3%, and the finished boards are not easy to peel or delaminate when bumped or wiped.

[0046] Compared with the finished product of Example 2, the finished product of Comparative Example 1 has more holes and obvious defects in its appearance, and the surface roughness is 1.2μm. The puttying and leveling process and the solid color mixed oil transition topcoat process are completely omitted. Only a single layer of polyurethane sealing primer is retained. The remaining coating, curing and grinding processes are completely consistent with the Example. The substrate defects are amplified by the mother-of-pearl paint and piano paint. The 2mm adhesion peeling area accounts for as high as 12%, indicating that the single layer of sealing primer has insufficient covering power and the paint film's peel resistance is reduced.

[0047] Compared with the finished product of Example 2, the finished product of Comparative Example 2 has polishing defects in appearance. Comparative Example 2 lacks fine grinding. The uniform 400-grit dry grinding resulted in a surface roughness Ra of 1.8μm and a gloss decay rate of 25%. The adhesion peeling area of ​​2mm cross-cut adhesion was as high as 40%, indicating that the interlayer adhesion of the finished product of Comparative Example 2 was extremely poor. The pearlescent color difference of the same batch was 4.5. Due to the fluctuation of the mother-of-pearl paint ratio and the incompatibility between strong banana oil and mother-of-pearl paint, the pearlescent effect of mother-of-pearl paint was out of control. The paint film durability of the finished product of Comparative Example 2 was poor. The core process of Comparative Example 2 was substandard, resulting in multiple defects.

[0048] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and are not intended to limit it. Although the present invention has been described in detail with reference to preferred embodiments, those skilled in the art should understand that modifications or equivalent substitutions can be made to the technical solutions of the present invention without departing from the spirit and scope of the technical solutions of the present invention, and all such modifications or substitutions should be covered within the scope of the claims of the present invention.

Claims

1. A method for composite processing of mother-of-pearl lacquer and piano lacquer, characterized in that, Includes the following steps: S1: Cut the UV board into pieces, apply putty to the surface of the processed UV board before painting, and then sand the entire board after the putty is applied. S2: Apply primer to the treated UV board surface, sand it after the primer has fully cured, apply mixed oil topcoat to the sanded primer surface, and sand it again after the mixed oil topcoat has cured. S3: Mix the mother-of-pearl color paint and mother-of-pearl paint main agent evenly at a mass ratio of 1:0.5 to obtain the mother-of-pearl paint mixture; spray the thinner onto the paint surface simultaneously during the coating process, apply the mother-of-pearl paint topcoat, and let the UV board coated with the mother-of-pearl paint topcoat stand and cure. S4: After the UV board has been left to stand for 4 days, apply two coats of piano lacquer evenly and let it stand for curing for more than 7 days. Then, use 320-grit sandpaper to wet grind the edges and corners of the workpiece, grind the irregular surfaces of the workpiece uniformly, and finely grind the dead corners, small steps, and gaps of the workpiece. Finally, grind the UY board as a whole, polish it, and perform appearance quality inspection to obtain the finished product.

2. The method for composite processing of mother-of-pearl lacquer and piano lacquer according to claim 1, characterized in that, In S1, the plastering treatment uses water-based wood plaster, and the plastering thickness is 0.2~0.5mm.

3. The method for composite processing of mother-of-pearl lacquer and piano lacquer according to claim 1, characterized in that, In S1, the overall sanding is done using 240-320 grit sandpaper.

4. The method for composite processing of mother-of-pearl lacquer and piano lacquer according to claim 1, characterized in that, In S2, the primer base material is selected as polyurethane sealing primer, and the mixed oil topcoat is selected as solid color mixed oil topcoat.

5. The method for composite processing of mother-of-pearl lacquer and piano lacquer according to claim 1, characterized in that, In S2, the primer is dry-sanded with 320-grit sandpaper after it has fully cured; the mixed oil topcoat is sanded with 400-600-grit sandpaper after it has cured.

6. The method for composite processing of mother-of-pearl lacquer and piano lacquer according to claim 1, characterized in that, In step S3, the mother-of-pearl paint and the mother-of-pearl paint main agent are mixed and stirred continuously for 3-5 minutes.

7. The method for composite processing of mother-of-pearl lacquer and piano lacquer according to claim 1, characterized in that, In S3, the diluent is selected from any one of propylene ester diluents, ketone reactive diluents, and butyl acetate.

8. The method for composite processing of mother-of-pearl lacquer and piano lacquer according to claim 1, characterized in that, In S4, the temperature during the settling stage is controlled at 18℃~28℃, and the relative humidity is controlled at 40%~70%.

9. The method for composite processing of mother-of-pearl lacquer and piano lacquer according to claim 1, characterized in that, In S4, the irregular surfaces of the workpiece are uniformly ground to 800 grit, and the dead corners, small steps, and gaps of the workpiece are finely ground to 1200-1500 grit; the overall grinding is carried out to 1000 grit.

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