Anti-oxidation black papermaking coating and method for preparing anti-oxidation black paperboard by using anti-oxidation black papermaking coating

Abstract

The invention belongs to the field of papermaking, and provides an antioxidant black papermaking coating and a method for preparing antioxidant black paperboard by using the antioxidant black papermaking coating. The antioxidant black papermaking coating is prepared from the following components in parts by weight: 10-20 parts of black pigment, 2-8 parts of a dispersing agent, 2.5-7.5 parts of an adhesive, 1 part of a defoaming agent, 2-8 parts of a water repellent agent, 1-20 parts of latex, 2.5-7.5 parts of an antioxidant and 200 parts of water. The invention also provides a method for preparing antioxidant black cardboard by using the antioxidant black papermaking coating, and the antioxidant black cardboard prepared by the method has a good antioxidant effect.

Description

Technical Field

[0001] The invention relates to the technical field of papermaking, in particular to an anti-oxidation black papermaking coating and a method for preparing anti-oxidation black card paper by using the same. Background Art

[0002] Black cardboard is a thick black cardboard with a large basis weight, small difference between the two sides, and high opacity. It is usually used for high-end products with high quality requirements, such as high-end gift boxes, mobile phone packaging boxes, clothing tags, high-end handbags, etc. The dyeing process in the production process of black cardboard usually consists of two parts: pulp dyeing and surface coating. Its black pigment components usually contain carbon black, iron black and other substances. It is very easy to undergo oxidation reactions during post-processing such as printing and hot stamping, resulting in discoloration, fading, and fading. In order to avoid the above problems, the industry usually coats the paper with a film or applies an antioxidant varnish before post-processing to delay oxidation. However, the above methods are usually easy to change the surface properties of black cardboard, affecting the use of paper, and there is also the problem of high cost. Summary of the invention

[0003] In order to overcome the shortcomings and deficiencies in the prior art, the present invention solves the problem of easy oxidation and fading of black cardboard during post-processing by adding an antioxidant in the surface coating process, replacing the existing method of laminating or coating with antioxidant varnish. The present invention provides an antioxidant black papermaking coating for surface coating, the coating is added with an alkali metal antioxidant, the antioxidant can react with oxidizing substances in the post-processing process, reduce the oxidation of black pigments by oxidizing substances, and thus achieve the purpose of delaying fading.

[0004] The technical solution adopted by the present invention is:

[0005] An anti-oxidation black papermaking paint is prepared by mixing the following components in parts by weight: 10-20 parts of black pigment, 2-8 parts of dispersant, 2.5-7.5 parts of adhesive, 1 part of defoamer, 2-8 parts of water repellent, 1-20 parts of latex, 2.5-7.5 parts of antioxidant and 200 parts of water.

[0006] Among them, the black pigment is one or a combination of graphite, carbon black, and iron black, the defoamer is a polyether defoamer, the adhesive is one or a combination of sodium carboxymethyl cellulose, oxidized starch, and native starch, the dispersant is sodium polyacrylate, the water repellent is polyamide polyurea resin, and the antioxidant is one or a combination of alkali metal salts such as sodium carbonate, sodium sulfite, and potassium sulfite.

[0007] A method for preparing the above-mentioned antioxidant papermaking black coating comprises the following steps:

[0008] (1) The above-mentioned black pigment, dispersant and water are stirred at 3000 RPM using a high-speed disperser, and heated to 95° C. for 15 minutes to fully disperse the black pigment;

[0009] (2) After the black pigment is dispersed, the above-mentioned weight parts of adhesive, defoamer, water repellent, and latex are added in sequence, the temperature is maintained at 95° C., and stirred at a speed of 1000 RPM for 30 min using a high-speed disperser;

[0010] (3) cooling to 45° C., adding the above-mentioned antioxidant in parts by weight, stirring at a speed of 200 RPM for 15 min, cooling to room temperature, and preparing an antioxidant papermaking black coating;

[0011] A method for preparing antioxidant black cardboard using the antioxidant black papermaking coating: after the pulp is put on the screen, formed, pressed and dried by a papermaking machine, the antioxidant black papermaking coating is applied to the formed base paper by a single-side scraper, and the coating amount is 8-15g / m 2 The coated paper is dried, calendered and rolled up to obtain an antioxidant black cardboard product.

[0012] The beneficial effects of the present invention are as follows: the antioxidant black papermaking coating of the present invention selects one or a combination of alkali metal salts such as sodium carbonate, sodium sulfite, potassium sulfite, etc. as an antioxidant, has low use cost and good antioxidant effect, effectively gives black card paper antioxidant properties, and extends the service life of black card paper. DETAILED DESCRIPTION

[0013] [Example 1]

[0014] An anti-oxidation black papermaking coating is prepared by mixing the following components in parts by weight: 20 parts of black pigment, 8 parts of dispersant, 7.5 parts of adhesive, 1 part of defoamer, 8 parts of water repellent, 20 parts of latex, 7.5 parts of antioxidant and 200 parts of water.

[0015] Among them, the black pigment is one or a combination of graphite, carbon black, and iron black, the defoaming agent is a polyether defoaming agent, the adhesive is sodium carboxymethyl cellulose, the dispersant is sodium polyacrylate, the water repellent is polyamide polyurea resin, and the antioxidant is a combination of alkali metal salts such as sodium carbonate and sodium sulfite.

[0016] A method for preparing the above-mentioned antioxidant papermaking black coating comprises the following steps:

[0017] (1) The above-mentioned black pigment, dispersant and water are stirred at 3000 RPM using a high-speed disperser, and heated to 95° C. for 15 minutes to fully disperse the black pigment;

[0018] (2) After the black pigment is dispersed, the above-mentioned weight parts of adhesive, defoamer, water repellent, and latex are added in sequence, the temperature is maintained at 95° C., and stirred at a speed of 1000 RPM for 30 min using a high-speed disperser;

[0019] (3) cooling to 45° C., adding the above-mentioned antioxidant in parts by weight, stirring at a speed of 200 RPM for 15 min, cooling to room temperature, and preparing an antioxidant papermaking black coating;

[0020] A method for preparing antioxidant black cardboard using the antioxidant black papermaking coating: after the pulp is put on the screen, formed, pressed and dried by a papermaking machine, the antioxidant black papermaking coating is applied to the formed base paper by a single-side scraper, and the coating amount is 8g / m 2 The coated paper is dried, calendered and rolled up to obtain an antioxidant black cardboard product.

[0021] [Example 2]

[0022] An anti-oxidation black papermaking paint is prepared by mixing the following components in parts by weight: 20 parts of black pigment, 8 parts of dispersant, 7.5 parts of adhesive, 1 part of defoamer, 2 parts of water repellent, 10 parts of latex, 7.5 parts of antioxidant and 200 parts of water.

[0023] Among them, the black pigment is one or a combination of graphite, carbon black, and iron black, the defoaming agent is a polyether defoaming agent, the adhesive is sodium carboxymethyl cellulose, the dispersant is sodium polyacrylate, the water repellent is polyamide polyurea resin, and the antioxidant is a combination of alkali metal salts such as sodium carbonate and potassium sulfite.

[0024] The preparation method of the antioxidant black papermaking coating is the same as that of Example 1.

[0025] A method for preparing antioxidant black cardboard using the antioxidant black papermaking coating: base paper is produced in a papermaking machine, and the antioxidant black papermaking coating is applied to the formed base paper by a single-sided scraper, with a coating amount of 8g / m 2 The coated paper is heated and dried to obtain an antioxidant black cardboard product.

[0026] [Example 3]

[0027] The invention discloses an anti-oxidation black papermaking coating, which is prepared by mixing the following components in parts by weight: 10 parts of black pigment, 2 parts of dispersant, 2.5 parts of adhesive, 1 part of defoamer, 2 parts of water repellent, 20 parts of latex, 2.5 parts of antioxidant and 200 parts of water.

[0028] Among them, the black pigment is one or a combination of graphite, carbon black, and iron black, the defoamer is a polyether defoamer, the adhesive is sodium carboxymethyl cellulose, the dispersant is sodium polyacrylate, the water repellent is polyamide polyurea resin, and the antioxidant is a combination of alkali metal salts such as sodium sulfite and potassium sulfite.

[0029] The preparation method of the antioxidant black papermaking coating is the same as that of Example 1.

[0030] A method for preparing antioxidant black cardboard using the antioxidant black papermaking coating: base paper is produced in a papermaking machine, and the antioxidant black papermaking coating is applied to the formed base paper by a single-sided scraper, with a coating amount of 15g / m 2 The coated paper is heated and dried to obtain an antioxidant black cardboard product.

[0031] [Example 4]

[0032] The invention discloses an anti-oxidation black papermaking coating, which is prepared by mixing the following components in parts by weight: 10 parts of black pigment, 2 parts of dispersant, 7.5 parts of adhesive, 1 part of defoamer, 2 parts of water repellent, 20 parts of latex, 7.5 parts of antioxidant and 200 parts of water.

[0033] The black pigment is one or a combination of graphite, carbon black and iron black, the defoamer is a polyether defoamer, the adhesive is a combination of sodium carboxymethyl cellulose and oxidized starch, the dispersant is sodium polyacrylate, the water repellent is polyamide polyurea resin, and the antioxidant is sodium carbonate.

[0034] The preparation method of the antioxidant black papermaking coating is the same as that of Example 1.

[0035] A method for preparing antioxidant black cardboard using the antioxidant black papermaking coating: base paper is produced in a papermaking machine, and the antioxidant black papermaking coating is applied to the formed base paper by a single-sided scraper, with a coating amount of 15g / m 2 The coated paper is heated and dried to obtain an antioxidant black cardboard product.

[0036] [Example 5]

[0037] An anti-oxidation black papermaking paint is prepared by mixing the following components in parts by weight: 10 parts of black pigment, 2 parts of dispersant, 5 parts of adhesive, 1 part of defoamer, 8 parts of water repellent, 1 part of latex, 5 parts of antioxidant and 200 parts of water.

[0038] Among them, the black pigment is one or a combination of graphite, carbon black, and iron black, the defoamer is a polyether defoamer, the adhesive is a combination of oxidized starch and native starch, the dispersant is sodium polyacrylate, the water repellent is polyamide polyurea resin, and the antioxidant is a combination of sodium carbonate and sodium sulfite.

[0039] The preparation method of the antioxidant black papermaking coating is the same as that of Example 1.

[0040] A method for preparing antioxidant black cardboard using the antioxidant black papermaking coating: base paper is produced in a papermaking machine, and the antioxidant black papermaking coating is applied to the formed base paper by a single-sided scraper, with a coating amount of 10 g / m 2 The coated paper is heated and dried to obtain an antioxidant black cardboard product.

[0041] The antioxidant level test of Examples 1-5 was performed using hydrogen peroxide, a strong oxidant.

[0042] Test conditions: Add 7% hydrogen peroxide to the weighing bottle until the liquid level is about 50%, cover the paper sample to be tested on the weighing bottle (completely cover the bottle mouth), and then compact the paper sample with the weighing bottle cap, and place it in a 70℃ blast drying oven. If no oxidative discoloration spots appear within the specified time, it is the current antioxidant level. The antioxidant level is shown in Table 1:

[0043] Table 1

[0044] grade 1 2 3 4 5 6 7 8 Time / min 30 60 90 120 150 180 210 240

[0045] The test results are shown in Table 2:

[0046] Table 2

[0047] sample Blank Example 1 Example 2 Example 3 Example 4 Example 5 Antioxidant Level 2 8 8 7 7 7

[0048] It can be seen from the test results that, compared with the untreated blank group black cardboard samples, the antioxidant performance of the black cardboard coated with the antioxidant black papermaking coating prepared by the present invention is significantly improved.

Claims

1. An antioxidant black papermaking coating, characterized in that: The invention is prepared by mixing the following components in parts by weight: 10-20 parts of black pigment, 2-8 parts of dispersant, 2.5-7.5 parts of adhesive, 1 part of defoamer, 2-8 parts of water repellent, 1-20 parts of latex, 2.5-7.5 parts of antioxidant, and 200 parts of water. The black pigment is one or a combination of graphite, carbon black, and iron black, the defoamer is a polyether defoamer, the adhesive is one or a combination of sodium carboxymethyl cellulose, oxidized starch, and native starch, the dispersant is sodium polyacrylate, the water repellent is polyamide polyurea resin, and the antioxidant is one or a combination of alkali metal salts such as sodium carbonate, sodium sulfite, and potassium sulfite.

2. The antioxidant black papermaking coating according to claim 1, characterized in that: The method for preparing the antioxidant black papermaking coating comprises the following steps: (1) Stir the above-mentioned black pigment, dispersant and water in a high-speed disperser at a speed of 3000 RPM, and heat to 95° C. for 15 minutes to fully disperse the black pigment; (2) After the black pigment is dispersed, add the above-mentioned adhesive, defoamer, water repellent, and latex in parts by weight in sequence, maintain the temperature at 95°C, and stir at a speed of 1000 RPM for 30 min using a high-speed disperser; (3) Cooling the mixture to 45° C., adding the above-mentioned antioxidant in parts by weight, and continuing to stir at a speed of 200 RPM for 15 min. Cooling the mixture to room temperature to obtain an antioxidant papermaking black coating.

3. A method for preparing antioxidant black cardboard using the antioxidant black papermaking coating, characterized in that: After the slurry is put on the screen, formed, pressed and dried by the paper machine, the antioxidant black papermaking coating is applied to the formed base paper by a single-sided scraper coating, with a coating amount of 8-15 g / m 2 The coated paper is dried, calendered and rolled up to obtain an antioxidant black cardboard product.