Dyes suitable for coloring wood carvings

Abstract

The present invention discloses a dye suitable for coloring wood carvings. Modified particles are added to the dye, and a core-shell structure is formed by coordinating a castor oil modified layer to form a three-layer composite structure. A drying agent is used to promote air curing of ricinoleic acid. The combination can greatly increase the hardness of the formed paint film, while also improving the ultraviolet shielding performance and the protection of coated objects such as wood carvings. Acrylate is added to the dye, and the two-component structure helps reduce costs and helps improve the water resistance, weather resistance and other properties of the paint film.

Description

Technical Field

[0001] The invention relates to the technical field of dyes, and in particular to a dye suitable for coloring wood carvings. Background Art

[0002] Dongyang wood carving is a carving art that mainly uses flat relief. Its characteristics are: multi-level relief, scattered perspective composition, and retention of flat decoration, thus forming its own distinctive characteristics. It is widely used in architecture, handicrafts and furniture decoration.

[0003] In order to meet people's aesthetic needs and protect the wood carvings, modern Dongyang wood carvings are generally painted, and the most common ones are water-based polyurethane wood paints. However, the films formed by common polyurethane paints on the market have defects such as low hardness and low UV shielding performance, which need to be improved. Summary of the Invention

[0004] To solve at least one of the above technical deficiencies, the present invention provides the following technical solutions:

[0005] The present application document discloses a dye suitable for coloring wood carvings, which comprises, by mass, 45-60 parts of a mixture of diisocyanate and alcohol, 1-3 parts of modified particles, 0.3-1.5 parts of a catalyst, 0.7-2.0 parts of a chain extender, 0.1-0.3 parts of a dispersant, 0.5-1.2 parts of a thickener, 15-25 parts of an acrylate, 0.5-2 parts of a curing agent, 0.1-0.3 parts of a drying agent, 0.1-0.4 parts of a defoaming agent, and 10-25 parts of water; wherein the modified particles have nano-titanium dioxide and nano-boron carbide as a core, a lignin shell, and the lignin shell is modified with castor oil.

[0006] This dye is added with modified particles, and the core-shell is combined with the castor oil modified layer to form a three-layer composite structure. The drying agent is used to promote the air curing of ricinoleic acid. The combination can greatly increase the hardness of the formed paint film, while improving the UV shielding performance and enhancing the protection of coated objects such as wood carvings.

[0007] The addition of acrylate to this dye and its two-component structure help reduce costs and improve the water resistance and weather resistance of the paint film.

[0008] Furthermore, the modified particles are prepared as follows: nano-titanium dioxide and nano-boron carbide powders are added to deionized water and ultrasonically dispersed to form a slurry, lignin is mixed with the slurry, and the mixture is stirred at 65-85° C. under alkaline conditions until the pH value of the solution is neutral, and the separated solid particles are dried and ground to obtain solid particles with nano-titanium dioxide and nano-boron carbide as the core and lignin as the shell;

[0009] The ricinoleic acid and solid particles are mixed in a solvent, and the ricinoleic acid and the lignin at the shell of the solid particles are esterified under the catalysis of an acidic catalyst, so that the lignin shell is modified with castor oil.

[0010] In this scheme, lignin is used to coat nano-titanium dioxide and nano-boron carbide powders through physical blending, and then ricinoleic acid is esterified with lignin under the action of an acidic catalyst to form a ricinoleic acid modified layer on the lignin shell. The entire process has the advantages of being simple and easy to operate.

[0011] Furthermore, the mass ratio of nano-titanium dioxide and nano-boron carbide is 1-2:0.4-0.6, the sum of the mass ratio of lignin to nano-titanium dioxide and nano-boron carbide is 2-4:1, and the mass ratio of ricinoleic acid to solid particles is 1-2:1. Under the limited ratio, it helps to improve the performance of the dye.

[0012] Furthermore, the ricinoleic acid reacts with the lignin at the shell of the solid particles at 100-150° C. for more than 10 hours.

[0013] Furthermore, the acidic catalyst is p-toluenesulfonic acid, and the solvent is acetone.

[0014] Furthermore, the alcohol is any one of polyethylene glycol, polypropylene glycol, and polycarbonate diol; the diisocyanate is any one of hexamethylene diisocyanate, isophorone diisocyanate, and toluene diisocyanate; the catalyst is any one of dibutyltin dilaurate and triethanolamine; and the chain extender is a mixture of 1,4-butanediol and dihydroxymethylpropionic acid in a mass ratio of 1-1.5:1.

[0015] Furthermore, the dispersant is ammonium polyacrylate, the thickener is any one of polyacrylamide and polyacrylic acid, the curing agent is trimethylolpropane, and the defoaming agent is an organopolysiloxane defoaming agent.

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

[0017] 1. The present invention adds three layers of composite modified particles to the dye, which can significantly improve the hardness of the paint film with a small amount of addition. Combined with the improvement of the ultraviolet shielding function, it has excellent protective performance for wooden objects such as wood carvings to which the paint film is attached. DETAILED DESCRIPTION

[0018] The present invention will be further described below with reference to specific embodiments.

[0019] Preparation of nano-titanium dioxide and nano-boron carbide powders: Boron carbide powder was added to a mixture of Tris-HCl buffer and ethanol, where the volume ratio of buffer to ethanol was 3:1 and the mass volume ratio of boron carbide to the mixture was 1g / 0.15L, and ultrasonic treatment was performed for 30min.

[0020] Dopamine hydrochloride was added to the ultrasonicated boron carbide dispersion at a mass ratio of dopamine hydrochloride to boron carbide of 0.5:1. The pH was adjusted to 8.5 with sodium hydroxide. The mixture was stirred magnetically for 2 hours, and then centrifuged and dried to obtain polydopamine-modified nano-boron carbide.

[0021] Ethanol, water, and isopropanol were mixed in a volume ratio of 15:5:80, and tetrabutyl titanate (mass-to-volume ratio of 3g:100ml) was added to form a precursor solution. Polydopamine-modified nano-boron carbide and coupling agent KH550 were added to the precursor solution and stirred for reaction for 4h. The solid-liquid separation and drying were performed to obtain nano-titanium dioxide and nano-boron carbide powders, wherein the amount of coupling agent added was 2% of the mass of the polydopamine-modified nano-boron carbide, and the polydopamine-modified nano-boron carbide was added according to a mass ratio of boron carbide to titanium dioxide of 3:1.

[0022] Preparation of modified particles:

[0023] The nano-titanium dioxide and nano-boron carbide powders prepared above were added to deionized water (mass to volume ratio of 1:10) and ultrasonically dispersed to form a slurry. Lignin was mixed with the slurry. The amount of lignin added was 2.5 times the mass of the nano-titanium dioxide and nano-boron carbide powders. The pH was adjusted to 8.5, and the temperature was raised to 80°C and mixed and stirred until the pH value of the solution was neutral (i.e., pH 7). The separated solid particles were filtered, washed, and dried, and then ground to obtain solid particles with nano-titanium dioxide and nano-boron carbide as the core and lignin as the shell. The coating amount of lignin was found to be 10%.

[0024] The ricinoleic acid and solid particles are mixed in the solvent acetone, the mass ratio of ricinoleic acid to solid particles is 1.5:1, and the sum of the masses of the two to the mass volume of acetone is 1:4. p-Toluenesulfonic acid is used as an acidic catalyst, and its addition amount is 1% of the solid particles. The reaction is carried out at a temperature of 100°C for 10 hours. Under the catalysis of the acidic catalyst, the ricinoleic acid and the lignin at the shell of the solid particles undergo esterification reaction, and the lignin shell is modified by castor oil. The modified particles are filtered, washed and dried to obtain modified particles.

[0025] The drying agent is obtained by mixing cobalt naphthenate and calcium naphthenate in a mass ratio of 1:1.

[0026] Example 1

[0027] The preparation of a dye suitable for coloring wood carvings is as follows: 50 parts by mass of a mixture of isophorone diisocyanate and polypropylene glycol (N210) (the mass ratio of isophorone diisocyanate to polypropylene glycol is 23:8) is added to a container, followed by adding 0.8 parts of dibutyltin dilaurate and 1.2 parts of 1,4-butanediol, heating to 75°C and reacting for 1.5 hours, cooling to 65°C, adding 1 g of dihydroxymethylpropionic acid and reacting for 10 minutes, then cooling to 40°C and adding 0.2 parts of polyacrylamine and 20 parts of acrylate, adjusting the pH value to 7 with triethylamine, and then adding 0.8 parts of ammonium polyacrylate, 0.7 parts of trimethylolpropane, 0.2 parts of a drying agent obtained by mixing cobalt cyclopentane and calcium cyclopentane in a mass ratio of 1:1, 2 parts of the modified particles prepared above, and 20 parts of deionized water, stirring and emulsifying, and finally adding an organopolysiloxane for defoaming to obtain the desired dye.

[0028] Example 2

[0029] The preparation of a dye suitable for coloring wood carvings is as follows: 49 parts by mass of a mixture of isophorone diisocyanate and polypropylene glycol (N210) (the mass ratio of isophorone diisocyanate to polypropylene glycol is 25:8) is added to a container, followed by adding 0.7 parts of dibutyltin dilaurate and 1.3 parts of 1,4-butanediol, heating to 75°C and reacting for 1.5 hours, cooling to 65°C, adding 1.1 g of dihydroxymethylpropionic acid and reacting for 10 minutes, then cooling to 40°C and adding 0.3 parts of polyacrylamine and 22 parts of acrylate, adjusting the pH value to 7 with triethylamine, and then adding 1.0 parts of ammonium polyacrylate, 0.6 parts of trimethylolpropane, 0.3 parts of a drying agent obtained by mixing cobalt cyclopentane and calcium cyclopentane in a mass ratio of 1:1, 2 parts of modified particles, and 20 parts of deionized water, stirring and emulsifying, and finally adding an organopolysiloxane for defoaming to obtain the desired dye.

[0030] Comparative Example 1

[0031] Compared with Example 1, the difference is that in this example, ricinoleic acid does not react with the solid particles having nano-titanium dioxide and nano-boron carbide as the core and lignin as the shell, but ricinoleic acid is directly mixed with the other components independently according to the amount added in Example 1.

[0032] Comparative Example 2

[0033] Compared with Example 1, the difference is that the modified particles in this example do not undergo the esterification and compounding process of titanium dioxide and boron carbide. Instead, commercially available nano-titanium dioxide powder and nano-boron carbide powder are directly mixed, added to deionized water, and then lignin is added.

[0034] The dyes prepared in the above examples and comparative examples were coated to form paint films, and the hardness and UV shielding properties of the paint films were tested, as shown in Table 1:

[0035] Table 1

[0036]

[0037] The UV shielding capabilities of the paint films formed in Example 1, Example 2 and Comparative Examples 1 and 2 all exceed 90%, which can better protect wood carvings and the like to which the paint films are attached. In addition, the hardness of the paint films is greatly improved, which can also improve the protection of the paint films.

[0038] In addition, other colorants may be added to the dye to impart different colors to the film layer. The colorant may be selected according to needs and will not be described in detail here.

[0039] The above are merely preferred embodiments of the present invention. The scope of protection of the present invention is not limited to the above embodiments. All technical solutions based on the principles of the present invention are within the scope of protection of the present invention. It should be noted that improvements and modifications that do not depart from the principles of the present invention are within the scope of protection of the present invention.

Claims

1. A dye suitable for coloring wood carvings, characterized in that: The invention comprises, by mass, 45-60 parts of a mixture of diisocyanate and alcohol, 1-3 parts of modified particles, 0.3-1.5 parts of a catalyst, 0.7-2.0 parts of a chain extender, 0.1-0.3 parts of a dispersant, 0.5-1.2 parts of a thickener, 15-25 parts of an acrylate, 0.5-2 parts of a curing agent, 0.1-0.3 parts of a drier, 0.1-0.4 parts of a defoamer, and 10-25 parts of water; wherein the modified particles have nano-titanium dioxide and nano-boron carbide as a core, a lignin shell, and the lignin shell is modified with castor oil; The modified particles are prepared as follows: nano-titanium dioxide and nano-boron carbide powders are added to deionized water and ultrasonically dispersed to form a slurry; lignin is mixed with the slurry; and the mixture is stirred at 65-85°C under alkaline conditions until the pH value of the solution is neutral; the separated solid particles are dried and ground to obtain solid particles with nano-titanium dioxide and nano-boron carbide as the core and lignin as the shell; The ricinoleic acid and solid particles are mixed in a solvent, and the ricinoleic acid and the lignin at the shell of the solid particles are esterified under the catalysis of an acidic catalyst, so that the lignin shell is modified with castor oil; The mass ratio of nano-titanium dioxide to nano-boron carbide is 1-2:0.4-0.6, the sum of the mass ratio of lignin to nano-titanium dioxide and nano-boron carbide is 2-4:1, and the mass ratio of ricinoleic acid to solid particles is 1-2:1; The ricinoleic acid reacts with the lignin at the shell of the solid particles at 100-150° C. for more than 10 hours; The alcohol is any one of polyethylene glycol, polypropylene glycol, and polycarbonate diol; the diisocyanate is any one of hexamethylene diisocyanate, isophorone diisocyanate, and toluene diisocyanate; the catalyst is any one of dibutyltin dilaurate and triethanolamine; and the chain extender is a mixture of 1,4-butanediol and dihydroxymethylpropionic acid in a mass ratio of 1-1.5:

1.

2. The dye suitable for coloring wood carvings according to claim 1, characterized in that: The acidic catalyst is p-toluenesulfonic acid, and the solvent is acetone.

3. The dye suitable for coloring wood carvings according to claim 1, characterized in that: The dispersant is ammonium polyacrylate, the thickener is any one of polyacrylamide and polyacrylic acid, the curing agent is trimethylolpropane, and the defoaming agent is an organopolysiloxane defoaming agent.

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