Zero-VOC (volatile organic compound) quick-drying water-based roller coating varnish as well as preparation method and application thereof

Abstract

The invention discloses zero-VOC (volatile organic compound) quick-drying water-based roller coating varnish as well as a preparation method and application thereof, and relates to the technical field of water-based roller coating varnish, the zero-VOC quick-drying water-based roller coating varnish is prepared from the following raw materials in percentage by weight: 65-75% of acrylic emulsion, 5-15% of polyurethane emulsion, 0.2-0.4% of wetting agent, 0.3-0.5% of defoaming agent, 2-5% of polyurethane flatting agent, 4-8% of wax emulsion and 0.3-0.5% of flatting agent, the Tg value Tg of the acrylic emulsion is more than or equal to 65 DEG C and less than or equal to 80 DEG C, the varnish is applied to wood product roller painting, and the baking temperature during roller painting construction is 70-100 DEG C. According to the invention, a coalescing agent is not added, zero VOC can be realized, the environment-friendly effect is realized, the formula cost is reduced, after roller painting construction, off-line direct stacking can be realized, the product does not contain an organic solvent, the performance is established very quickly after baking, the production efficiency is improved, and the labor cost is reduced.

Description

Technical Field

[0001] The invention relates to the technical field of water-based roller coating clear topcoat, in particular to a zero-VOC quick-drying water-based roller coating clear topcoat and a preparation method and application thereof. Background Art

[0002] At present, after the water-based clear topcoat used for roller coating is applied, the wooden products need to be laid on their sides when they come off the production line. The hardness, anti-stickiness and anti-scratch properties are slowly established and they cannot be directly stacked, which wastes manpower and working hours.

[0003] In order to improve the roller coating production efficiency and save labor costs, the present invention provides a zero-VOC quick-drying water-based roller coating clear topcoat, which can be directly stacked off the production line after roller coating construction. Summary of the invention

[0004] The purpose of the present invention is to provide a zero-VOC quick-drying water-based roller coating clear topcoat and a preparation method and application thereof, so as to solve the problem that traditional water-based roller coating clear topcoat cannot be directly stacked off the production line after construction.

[0005] In order to solve the above technical problems, the present invention provides a zero-VOC quick-drying water-based roller coating clear topcoat, which comprises the following raw materials in weight percentage: 65-75% acrylic emulsion, 5-15% polyurethane emulsion, 0.2-0.4% wetting agent, 0.3-0.5% defoaming agent, 2-5% polyurethane leveling agent, 4-8% wax emulsion, 0.3-0.5% leveling agent, 0.5-1% thickener, and the balance water.

[0006] Furthermore, the Tg value of acrylic emulsion is 65℃≤Tg≤80℃. When the Tg value is greater than 80℃, the film-forming property is poor, which easily leads to poor film formation. When the Tg value is less than 65℃, the performance is slowly established, the hardness and anti-sticking are poor, which easily leads to re-sticking. Polyurethane is mixed to improve the flexibility and film-forming property of the product.

[0007] The present invention also provides a method for preparing a zero-VOC quick-drying water-based roller coating clear topcoat.

[0008] S1. Raw materials preparation;

[0009] S2, batching and pre-dispersion;

[0010] S3, after grinding and dispersing, the finished product is obtained.

[0011] Further, the S2 includes:

[0012] S2.1. Add the prepared raw materials into the mixer according to the formula ratio;

[0013] S2.2. Use a stirrer to perform preliminary mixing and stirring at a speed of 500-1500r / min to fully pre-disperse the pigment and filler in the resin to form a relatively uniform slurry.

[0014] Furthermore, the S3 specifically includes adding the pre-dispersed slurry into a sand mill for grinding and dispersion, so that the pigment and filler are further refined and evenly dispersed in the resin.

[0015] The invention also provides a method for roller coating wooden products with the zero-VOC quick-drying water-based roller coating clear topcoat, wherein the baking temperature during the roller coating construction is 70° C.-100° C.

[0016] Compared with the prior art, the present invention has the following beneficial effects:

[0017] 1. The traditional water-based roller coating clear topcoat needs to add 3-6% of film-forming aids, which produces VOC. The present invention does not need to add film-forming aids, can achieve zero VOC, is environmentally friendly and reduces the formulation cost.

[0018] 2. The conventional water-based roller coating clear topcoat cannot be stacked directly after construction. The film-forming aid required by the product is slowly cross-linked during the volatilization process, and the performance is slowly established. The roller coating of the present invention can be stacked directly after construction. The product does not contain organic solvents, and the performance is established very quickly after baking, which improves production efficiency while reducing labor costs. DETAILED DESCRIPTION

[0019] The technical solutions in the embodiments of the present invention are described clearly and completely below. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of them. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0020] Embodiment 1

[0021] Raw materials:

[0022] Prepare the following raw materials in weight percentage: 65% acrylic emulsion, 15% polyurethane emulsion, 0.2% wetting agent, 0.3% defoaming agent, 2% polyurethane leveling agent, 4% wax emulsion, 0.3% leveling agent, 0.5% thickener, and the balance is water.

[0023] Preparation method:

[0024] Add the prepared raw materials into the agitator according to the formula ratio, and stir at a speed of 500-1500r / min to fully pre-disperse the pigment and filler in the resin to form a relatively uniform slurry.

[0025] The pre-dispersed slurry is added to a sand mill for grinding and dispersion, so that the pigment and filler are further refined and evenly dispersed in the resin to obtain a finished product 1.

[0026] Embodiment 2

[0027] Prepare the following raw materials in weight percentage: 70% acrylic emulsion, 10% polyurethane emulsion, 0.3% wetting agent, 0.4% defoaming agent, 3.5% polyurethane leveling agent, 6% wax emulsion, 0.4% leveling agent, 0.7% thickener, and the balance is water.

[0028] The finished product 2 was obtained according to the preparation method of Example 1.

[0029] Embodiment 3

[0030] Prepare the following raw materials in weight percentage: 75% acrylic emulsion, 5% polyurethane emulsion, 0.4% wetting agent, 0.5% defoaming agent, 5% polyurethane leveling agent, 8% wax emulsion, 0.5% leveling agent, 1% thickener, and the balance is water.

[0031] The finished product 3 was obtained according to the preparation method of Example 1.

[0032] Comparative Example 1

[0033] Prepare the following raw materials in weight percentage: 65% acrylic emulsion, 15% polyurethane emulsion, 0.2% wetting agent, 0.3% defoaming agent, 2% polyurethane leveling agent, 4% wax emulsion, 0.3% leveling agent, 0.5% thickener and 5% dipropylene glycol methyl ether, and the balance is water.

[0034] Comparative product 1 was obtained according to the preparation method of Example 1.

[0035] Comparative Example 2

[0036] Prepare the following raw materials in weight percentage: prepare the following raw materials in weight percentage: 70% acrylic emulsion, 10% polyurethane emulsion, 0.3% wetting agent, 0.4% defoaming agent, 3.5% polyurethane leveling agent, 6% wax emulsion, 0.4% leveling agent, 0.7% thickener and 5% dipropylene glycol methyl ether, and the balance is water.

[0037] Comparative product 2 was obtained according to the preparation method of Example 1.

[0038] Comparative Example 3

[0039] Prepare the following raw materials in weight percentage: 75% acrylic emulsion, 5% polyurethane emulsion, 0.4% wetting agent, 0.5% defoaming agent, 5% polyurethane leveling agent, 8% wax emulsion, 0.5% leveling agent, 0.7% thickener and 6% dipropylene glycol butyl ether, and the balance is water.

[0040] Comparative product 3 was obtained according to the preparation method of Example 1.

[0041] Comparative Example 4

[0042] Prepare the following raw materials in weight percentage: 47% acrylic emulsion, 8% polyurethane emulsion, 0.2% wetting agent, 0.3% defoaming agent, 20% white slurry, 3% polyurethane leveling agent, 5% wax emulsion, 0.3% leveling agent, 0.5 thickener, 3% dipropylene glycol methyl ether, 3% dipropylene glycol butyl ether, and the balance is water.

[0043] Comparative product 4 was obtained according to the preparation method of Example 1.

[0044] Construction technology of zero VOC quick-drying water-based roller coating clear topcoat

[0045] After the clear topcoats provided in the above-mentioned embodiments 1 to 3 and comparative examples 1 to 4 were dried after plate making, the clear topcoats were roller-coated on the same kind of wooden products under the same conditions. The baking temperature of the finished products 1, 2 and 3 obtained in embodiments 1 to 3 was 70°C-100°C during roller coating, and the comparative products 1, 2, 3 and 4 obtained in comparative examples 1 to 4 were all at conventional temperatures. The paint layers formed after roller coating were subjected to relevant performance tests, the leveling test was a visual scoring method, the adhesion test was based on the reference standard GB / T9286, the gloss test was based on the reference standard GB / T9754, the hardness test was based on the reference standard GB / T6739-2006, the abrasion resistance test was based on the reference standard GB / T1768, the storage stability test was based on the reference standard GB / T9274, the surface drying time was detected by the finger touch method, and the actual drying time was detected by the filter paper pressing method or the blade scraping method.

[0046] After testing, the leveling, adhesion, gloss, hardness, abrasion resistance and storage stability of the clear topcoat in Examples 1 to 3 and Comparative Examples 1 to 4 are very similar, while the surface drying time of Examples 1 to 3 is slightly shorter than that of Comparative Examples 1 to 4, and the actual drying time of Examples 1 to 3 is significantly shorter than that of Comparative Examples 1 to 4. Among Examples 1 to 3, the surface drying time of Finished Product 1, Finished Product 2 and Finished Product 3 are relatively similar, while the actual drying time of Finished Product 1 is the shortest, and Examples 1 to 3 produce no VOC.

Claims

1. A zero-VOC quick-drying water-based roller coating clear topcoat, characterized in that: The invention comprises the following raw materials in weight percentage: 65-75% of acrylic emulsion, 5-15% of polyurethane emulsion, 0.2-0.4% of wetting agent, 0.3-0.5% of defoaming agent, 2-5% of polyurethane leveling agent, 4-8% of wax emulsion, 0.3-0.5% of leveling agent, 0.5-1% of thickener and the balance of water.

2. A zero-VOC quick-drying water-based roller coating clear topcoat as claimed in claim 1, characterized in that: The Tg value of acrylic emulsion is 65℃≤Tg≤80℃.

3. A method as claimed in claim 1 2. The method for preparing the zero-VOC quick-drying water-based roller coating clear topcoat according to any one of the preceding claims, characterized in that: The following steps are involved: S1. Raw materials preparation; S2, batching and pre-dispersion; S3, after grinding and dispersing, the finished product is obtained.

4. The method for preparing a zero-VOC quick-drying water-based roller coating clear topcoat as claimed in claim 3, characterized in that: The S2 includes: S2.

1. Add the prepared raw materials into the mixer according to the formula ratio; S2.2, use a stirrer to perform preliminary mixing at a speed of 500- The mixing is carried out at 1500r / min to fully pre-disperse the pigment and filler in the resin to form a relatively uniform slurry.

5. The method for preparing a zero-VOC quick-drying water-based roller coating clear topcoat as claimed in claim 4, characterized in that: The S3 specifically includes adding the pre-dispersed slurry into a sand mill for grinding and dispersion, so that the pigment and filler are further refined and evenly dispersed in the resin.

6. A method for roller coating a wood product using the zero-VOC quick-drying water-based roller coating clear topcoat as claimed in claim 2, characterized in that: The baking temperature during the roller coating construction is 70° C.-100° C.