A production process of a paint door by a processing mode of a paint-free door

Abstract

The application discloses a kind of paint door production processes of processing mode of improving paint door, belong to wooden paint product technical field.The application improves traditional paint door production process in combination with paint product processing method, first pretreatment is carried out to core material, density board, wood skin, then wood skin is adhered with polypropylene fiber cloth, composite wood skin is made, subsequently composite wood skin is glued with density board and is hot-pressed and is attached, UV roll coating is carried out to the obtained skinned density board, paint panel is obtained, take paint panel and core material and are cold-pressed and assembled to obtain semi-finished product, finally cut, edge sealing, unlocking, packaging are obtained skinned paint wood door.The application first uses panel to paint well and then carries out assembly, and the processing procedure of traditional ten or so is significantly shortened, and the whole production cycle is shortened by 8-10 days compared with the last one, and the labor intensity of workers is greatly reduced, the product quality is linearly increased, the yield is greatly improved, and has good market competitiveness.

Description

TECHNICAL FIELD

[0001] The application belongs to the technical field of wood paint products, and particularly relates to a paint door production process for improving a paint-free door processing method. BACKGROUND

[0002] At present, paint products in the industry are generally first made into components, and then painted on the surface after the product is assembled and formed. The paint-free product is directly assembled with other components to form a product by using a treated surface veneer, and therefore the production efficiency, quality stability and cost performance of the paint-free product are higher than those of the paint product. However, compared with the paint-free product, the paint product has many high-quality performances such as brighter color, stronger visual impact, better surface smoothness, easy to wash, better moisture resistance and the like. Even though the paint-free product has obvious advantages in production efficiency and the like, the paint product is still mainly used in many scenes at present.

[0003] Based on the above, simplifying and shortening the production process of the paint product is the research focus in the industry at present. Taking a veneer paint wooden door as an example, the traditional production process is very complicated, and the process includes: material preparation-cold pressing-sanding-hot pressing veneer-edge punching-edge sealing-lock hole opening-polishing-rolling coating-door inspection-packaging. The process has obvious defects such as many production processes, long cycle, low efficiency, low product qualification rate and high labor intensity of workers. A more prominent problem is that the wooden product will shrink or expand due to the change of humidity in the air during the production process, which significantly reduces the qualification rate of the product at the paint end, and the labor cost sharply rises in the whole manufacturing process due to the continuous assembly of parts.

[0004] Therefore, it is of great significance to improve the production process of the veneer paint wooden door to improve product quality, improve production efficiency and reduce labor intensity of workers. SUMMARY

[0005] In view of the complicated traditional production process, the purpose of the present application is to provide a paint door production process for improving a paint-free door processing method. The present application combines the processing method of the paint-free product, uses a special modified white latex to bond the wood veneer and the polypropylene fiber cloth as a composite wood veneer, then further hot-presses and bonds the composite wood veneer with the density board, and then performs UV rolling coating to obtain a paint veneer, and finally directly assembles and presses the paint veneer and the core material to manufacture a door leaf. The new process provided by the present application shortens the whole production cycle by 8-10 days compared with the traditional production process of the veneer paint wooden door, can significantly reduce the labor intensity of workers, and can improve the qualification rate of the paint end from 75% to 99%, so that the product quality is directly improved and the product has good market competitiveness.

[0006] To achieve the above purpose, the present application specifically adopts the following scheme:

[0007] The application provides a paint door production process of a paint door processing mode, comprising the following steps:

[0008] Step one: selecting core material, density board and wood skin without obvious defects, and spraying and drying the selected raw materials for standby;

[0009] Step two: taking the wood skin obtained in step one, bonding the wood skin with polypropylene fiber cloth to prepare a composite wood skin, and then hot pressing and bonding the composite wood skin with the density board to obtain a skinned density board;

[0010] Step three: UV roll coating the skinned density board obtained in step two to obtain a paint panel;

[0011] Step four: taking the paint panel obtained in step three and the core material, and cold pressing and assembling to obtain a semi-finished product;

[0012] Step five: cutting, edge sealing, locking and packaging the semi-finished product in sequence to obtain a skinned paint wood door.

[0013] As preferred, the core material in step one is selected from solid wood or solid wood framework plus filler; the density board is selected from high-density fiber board or medium-density fiber board, and the density is 0.7-0.9 g / cm 3 ; the wood skin material is selected from black walnut or cherry wood, and the thickness is 0.08-0.12 mm; the spraying and drying control the water content to be 10%-12%.

[0014] As preferred, the bonding of the wood skin with the polypropylene fiber cloth in step two and the hot pressing and bonding of the composite wood skin with the density board both adopt modified white latex, and the preparation method of the modified white latex is as follows: adding chitosan into a polyvinyl alcohol solution and mixing to serve as an emulsifier system, slowly adding vinyl acetate ethylene, tertiary carbon acid ethylene and initiator solution into the diluted emulsifier system under the condition of 75-85 ℃, continuing to heat and fully polymerize after the dropping is completed, then adding dibutyl phthalate and octanol and mixing to obtain an emulsion, and finally adding melamine formaldehyde resin into the obtained emulsion and fully dispersing to obtain the modified white latex.

[0015] As preferred, the preparation raw materials of the modified white latex are as follows in terms of weight fraction: polyvinyl alcohol 3-9 parts, chitosan 0.5-2 parts, vinyl acetate ethylene 45-68 parts, tertiary carbon acid ethylene 7-14 parts, initiator (ammonium persulfate) 0.2-0.5 parts, dibutyl phthalate 2-6 parts, octanol 1-3 parts, melamine formaldehyde resin 6-12 parts, and water is sufficient.

[0016] The application adopts natural wood skin and polypropylene fiber cloth to make composite wood skin, which not only retains the appearance, touch and texture of the surface wood skin, but also reduces the thickness of the wood skin and the cost; the polypropylene fiber cloth has high tensile strength and elastic modulus, which can effectively enhance the strength of the wood skin and improve the overall stability of the door leaf. For the bonding between the wood skin, the polypropylene fiber cloth and the density board, the application prepares modified white latex with ethylene-vinyl acetate as the main monomer and vinyl versatate as the crosslinking monomer, which can greatly improve the adhesive force and water resistance of the glue, and chitosan and melamine formaldehyde resin can further enhance the bonding strength and heat resistance, so that the prepared high-performance modified white latex can provide good stability and strong bonding force for the composite wood skin and the skinned density board.

[0017] As preferred, the thickness of the composite wood skin in step two is 0.16-0.2 mm, and the hot-pressing and bonding refers to bonding the side of the composite wood skin with the polypropylene fiber cloth to the density board.

[0018] As preferred, the parameters of the hot-pressing and bonding are: temperature 120-135℃, pressure 5-6 MPa, and time 10-15 min.

[0019] As preferred, the hardness of the paint used in the UV roll coating in step three is not less than 3H.

[0020] As preferred, the two-component spliced board glue is used for cold pressing of the paint panel and the core material in step four.

[0021] As preferred, the parameters of the cold pressing in step four are: pressure 7.4-8 MPa and processing time 10-14 h.

[0022] Compared with the prior art, the application has the following beneficial effects:

[0023] The present application combines the processing technology of paint-free products, and a new production process is improved for the complicated production process of the veneer paint wooden door. The new process is: material preparation-hot pressing veneer-rolling-cooling- new line (edge punching-sealing-unlocking connection)-door inspection-packaging. The present application bonds the veneer with polypropylene fiber cloth to make a composite veneer, and at the same time, a modified white latex is used to make the composite veneer and the density board into a veneer density board with good stability; the polypropylene fiber cloth cooperates with the veneer to significantly improve the mechanical properties and processability of the woodworking assembly, while reducing the thickness of the veneer used and reducing the cost. The present application first paints the panel well and then assembles, which significantly shortens the traditional processing procedure of more than ten procedures, and the whole production cycle is shortened by 8-10 days compared with the previous process; at the same time, the veneer process is changed from the whole door into the pressing machine to the panel into the pressing machine, which greatly reduces the labor intensity of workers, and the paint end qualification rate is also improved from 75% of the traditional process to 99%. The present application has low process turnover, the product quality is straight up, the good product rate is greatly improved, and the quality of the product is further guaranteed. DETAILED DESCRIPTION

[0024] In order to make the purpose, technical scheme and advantages of the present application clearer, the technical scheme of the present application will be described clearly and completely below in combination with examples. If the specific conditions are not specified in the examples, the conventional conditions or the conditions recommended by the manufacturer are used. If the manufacturers of the reagents or instruments are not specified, they are all conventional products that can be purchased on the market.

[0025] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description of the application herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0026] In view of the complicated traditional process, the new process adopted by the present application is: material preparation-hot pressing veneer-rolling-cooling-new line (edge punching-sealing-unlocking connection)-door inspection-packaging. The new process of the present application combines the processing method of paint-free products, first paints the panel well and then assembles, at the same time, uses higher hardness paint, increases the intermediate section of the semi-finished product contact surface rubber strip to reduce friction, changes the plastic track and rubber wheel to solve the impression, prevents the defects such as scratch paint surface and edge collapse.

[0027] Example 1

[0028] A production process of a veneer paint wooden door, comprising:

[0029] 1. Selecting a solid wood board and a medium density fiber board (0.7 g / cm 3)、 black walnut skin (processed to 0.1 mm thick), the selected raw material is subjected to steam spraying, drying to a moisture content of 10% for standby.

[0030] 2, by weight parts of polyvinyl alcohol (PVA1799, same below) 6, chitosan 1.2, vinyl acetate 55, tertiary carbonic acid vinyl ester 11, ammonium persulfate 0.35, dibutyl phthalate 4, octanol 2, melamine formaldehyde resin 10, water enough. To the polyvinyl alcohol solution (85℃), add chitosan and mix well as emulsifier system, at 80℃, slowly add vinyl acetate, tertiary carbonic acid vinyl ester and ammonium persulfate solution to the diluted emulsifier system, after dropping, continue to heat and polymerize fully, then add dibutyl phthalate and octanol, stir well, adjust pH (7.5) and viscosity (9000 mPa·s) to get emulsion, finally add melamine formaldehyde resin to the obtained emulsion and disperse fully, to get modified white latex.

[0031] 3, take the treated wood skin, use the above modified white latex to bond (coating amount 0.02 g / cm 2 ) with polypropylene fiber cloth (fiber diameter not more than 12μm, area density 44 g / m 2 , same below) to make composite wood skin (0.18 mm thick); then evenly apply modified white latex (coating amount 0.03 g / cm 2 ) on one side surface of medium density fiberboard, bond the polypropylene fiber cloth side of the composite wood skin with the coated side of the medium density fiberboard, put into the hot press, heat press bonding at 5.5 MPa, 125℃ for 12 min to get the veneered density board.

[0032] 4, UV roll coating (use silicon modified polyurethane resin SJ-5021, Jining, Shandong) the obtained veneered density board to get the painted panel.

[0033] 5, take the obtained painted panel and solid wood board, evenly apply two-component spliced board glue (BAINIAN ZBL-A803, solid content 53%, coating amount 0.045 g / cm 2 ) on the non-wood skin side of the painted panel and both sides of the solid wood board, assemble the painted panel with the solid wood board, put the assembled workpiece into the cold press, cold press at 7.6 MPa for 12 h to make the semi-finished product.

[0034] 6, cut, edge seal, lock opening and package the semi-finished product in sequence to get the veneered painted wooden door.

[0035] Example 2

[0036] A production process of veneered painted wooden door, comprising:

[0037] 1. Selecting the solid wood board without obvious defects, medium density fiberboard (0.7 g / cm 3 ), black walnut skin (processed to 0.1 mm thick), the selected raw materials are sprayed, dried to 12% moisture content for use.

[0038] 2. The polyvinyl alcohol is 5 parts, the chitosan is 1.5 parts, the vinyl acetate is 45 parts, the tertiary carbonic acid vinyl ester is 7 parts, the ammonium persulfate is 0.2 parts, the dibutyl phthalate is 2 parts, the octanol is 1 part, the melamine formaldehyde resin is 6 parts, and the water is enough. Add chitosan to the polyvinyl alcohol solution (85℃) and mix well as an emulsifier system. At 80℃, slowly add vinyl acetate, tertiary carbonic acid vinyl ester and ammonium persulfate solution to the diluted emulsifier system. After dropping, continue to heat and polymerize fully, then add dibutyl phthalate and octanol, stir well, adjust pH (7.5) and viscosity (9000 mPa·s) to get the emulsion. Finally, add melamine formaldehyde resin to the obtained emulsion and disperse fully to get the modified white latex.

[0039] 3. Take the treated wood skin and use the modified white latex to bond it with polypropylene fiber cloth (glue amount 0.02 g / cm 2 ). Make composite wood skin (0.18 mm thick). Then evenly apply modified white latex (glue amount 0.03 g / cm 2 ) on one side of the medium density fiberboard. Bond the composite wood skin polypropylene fiber cloth side with the medium density fiberboard glue side. Put it into the hot press and heat press at 6 MPa, 120℃ for 15 min to get the skinned density board.

[0040] 4. UV roll coating (use silicon modified polyurethane resin SJ-5021, Jining, Shandong) the obtained skinned density board to get the painted panel.

[0041] 5. Take the obtained painted panel and solid wood board. Evenly apply two-component panel glue (BAINIAN ZBL-A803, solid content 53%, glue amount 0.045 g / cm 2 ) on the non-wood skin side of the painted panel and both sides of the solid wood board. Assemble the painted panel with glue on one side with the solid wood board. Put the assembled workpiece into the cold press and cold press at 7.4 MPa for 14 h to make the semi-finished product.

[0042] 6. Cut, edge seal, lock and package the semi-finished product in sequence to get the skinned painted wood door.

[0043] Example 3

[0044] A production process of skinned painted wood door, comprising:

[0045] 1. Selecting the wood board without obvious defects, medium density fiberboard (0.8 g / cm 3 ), black walnut skin (processed to 0.12 mm thick), the selected raw materials are sprayed, dried to 10% moisture content for standby.

[0046] 2. The polyvinyl alcohol 6 parts, chitosan 1 part, vinyl acetate 68 parts, tertiary carbonic acid ethylene 14 parts, ammonium persulfate 0.5 parts, dibutyl phthalate 6 parts, octanol 3 parts, melamine formaldehyde resin 12 parts, water is enough. Add chitosan to the polyvinyl alcohol solution (85℃) and mix well as an emulsifier system, slowly add vinyl acetate, tertiary carbonic acid ethylene and ammonium persulfate solution to the diluted emulsifier system at 80℃, continue to polymerize after dropping, then add dibutyl phthalate and octanol, stir well, adjust pH (7.5) and viscosity (9500 mPa·s) to get the emulsion, finally add melamine formaldehyde resin to the obtained emulsion and disperse well, to get the modified white latex.

[0047] 3. Take the treated wood skin, use the above modified white latex to bond it with polypropylene fiber cloth (glue amount 0.02 g / cm 2 ), to make composite wood skin (0.2 mm thick); then evenly apply modified white latex (glue amount 0.03 g / cm 2 ) on one side surface of the medium density fiberboard, bond the composite wood skin polypropylene fiber cloth side with the medium density fiberboard glue side, put it into the hot press, hot press bonding at 5 MPa, 130℃ for 10 min, to get the skinned density board.

[0048] 4. UV roll coating (using silicon modified polyurethane resin SJ-5021, Jining, Shandong) is performed on the obtained skinned density board to get the painted panel.

[0049] 5. Take the obtained painted panel and wood board, evenly apply two-component spliced board glue (BAINIAN ZBL-A803, solid content 53%, glue amount 0.045 g / cm 2 ) on the non-wood skin side of the painted panel and both sides of the wood board, assemble the painted panel with glue on one side with the wood board, put the assembled workpiece into the cold press, cold press at 8 MPa for 10 h to make the semi-finished product.

[0050] 6. The semi-finished product is cut, edge sealed, unlocked and packaged in sequence to get the skinned painted wood door.

[0051] Comparative Example 1

[0052] Refer to the step parameters of Example 1, the difference is that the white latex prepared by using the following raw materials is used instead of the adhesive to prepare the composite wood skin and hot press bonding to prepare the skinned density board.

[0053] Without adding tert-butyl ethylene carbonate, the raw materials for preparation are: 6 parts polyvinyl alcohol, 1.2 parts chitosan, 55 parts vinyl vinyl acetate, 0.35 parts ammonium persulfate, 4 parts dibutyl phthalate, 2 parts octanol, 10 parts melamine-formaldehyde resin, and sufficient water.

[0054] Comparative Example 2

[0055] Referring to the steps and parameters of Example 1, the difference lies in the use of white latex prepared from the following raw materials to replace adhesives in the preparation of composite wood veneer and hot-press bonding to prepare veneer MDF.

[0056] Without adding chitosan and melamine-formaldehyde resin, the raw materials for preparation are: 6 parts polyvinyl alcohol, 55 parts vinyl acetate, 11 parts tert-carbonate, 0.35 parts ammonium persulfate, 4 parts dibutyl phthalate, 2 parts octanol, and sufficient water.

[0057] Comparative Example 3

[0058] Referring to the steps and parameters of Example 1, the difference is that black walnut veneer (processed to a thickness of 0.18 mm) is directly bonded to the glued side of the medium-density fiberboard and hot-pressed together to prepare veneer MDF.

[0059] Test case

[0060] The performance of the samples prepared in Examples 1-3 and Comparative Examples 1-3 was tested (GB / T 17657-2022 "Test Methods for Physical and Chemical Properties of Wood-based Panels and Decorative Wood-based Panels"), and the results are as follows.

[0061] Table 1

[0062]

[0063] It is evident that this invention significantly shortens the production process while substantially improving the mechanical properties and stability of the resulting product. The process of this invention significantly improves production efficiency, reduces the labor intensity of workers, and enhances product quality, demonstrating promising application prospects.

[0064] The embodiments described above are merely preferred embodiments of the present invention, and while the descriptions are specific and detailed, they are not intended to limit the present invention. It should be noted that various changes and modifications can be made to the present invention by those skilled in the art. Any modifications, equivalent substitutions, improvements, etc., made within the concept and principles of the present invention should be included within the scope of protection of the present invention.

Claims

1. A modified paint-free door manufacturing process, characterized in that, Includes the following steps: Step 1: Select core material, MDF, and wood veneer without obvious defects, and steam and dry the selected raw materials for later use; The core material is selected from solid wood or a solid wood frame with filler, and the MDF is selected from high-density fiberboard or medium-density fiberboard with a density of 0.7-0.9 g / cm³. 3 The veneer material is selected from black walnut or cherry wood, with a thickness of 0.08-0.12 mm. The moisture content is controlled to be 10%-12% through steaming and drying. Step 2: Take the wood veneer obtained in Step 1 and bond it with polypropylene fiber cloth to make composite wood veneer. Then, glue the composite wood veneer to the MDF and heat-press it to obtain veneer MDF. In this process, modified white latex is used for bonding wood veneer to polypropylene fiber cloth and hot-pressing composite wood veneer to MDF. The preparation method of the modified white latex is as follows: chitosan is added to polyvinyl alcohol solution and mixed and stirred to form an emulsifier system. At 75-85℃, vinyl acetate, ethylene tert-carbonate and initiator solution are slowly added dropwise to the diluted emulsifier system. After the addition is completed, the temperature is maintained to fully polymerize. Then, the temperature is lowered to room temperature and dibutyl phthalate and octanol are added and stirred to obtain an emulsion. Finally, melamine-formaldehyde resin is added to the obtained emulsion and fully dispersed to obtain the final product. Step 3: Apply UV roller coating to the veneer MDF obtained in Step 2 to obtain a painted panel; Step 4: Take the painted panel and core material obtained in Step 3, and assemble them by cold pressing to obtain a semi-finished product; Step 5: Cut, seal, unlock, and package the semi-finished product in sequence to obtain the veneered and painted wooden door.

2. The paint-painted door production process according to claim 1, characterized in that, The modified white latex is prepared by the following raw materials in parts by weight: 3-9 parts polyvinyl alcohol, 0.5-2 parts chitosan, 45-68 parts vinyl acetate, 7-14 parts ethylene tert-carbonate, 0.2-0.5 parts initiator, 2-6 parts dibutyl phthalate, 1-3 parts octanol, 6-12 parts melamine-formaldehyde resin, and sufficient water.

3. The paint-painted door production process according to claim 1, characterized in that, The thickness of the composite wood veneer mentioned in step two is 0.16-0.2 mm, and hot pressing refers to bonding one side of the composite wood veneer polypropylene fiber cloth to the MDF.

4. The paint-painted door production process according to claim 3, characterized in that, The parameters for hot pressing are: temperature 120-135℃, pressure 5-6 MPa, and time 10-15 min.

5. The paint-painted door production process according to claim 1, characterized in that, The hardness of the paint used for UV roller coating in step three shall not be less than 3H.

6. The paint-painted door production process according to claim 1, characterized in that, In step four, the painted panel and core material are cold-pressed using a two-component adhesive.

7. The paint-painted door production process according to claim 1, characterized in that, The parameters for cold pressing in step four are: pressure 7.4-8 MPa and processing time 10-14 h.

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