阅读说明：本技术 一种漂白组合物及其制备方法和橄榄木材的漂白处理方法 (Bleaching composition, preparation method thereof and bleaching treatment method of olive wood ) 是由 佘学彬 仲利涛 张念椿 杨亮庆 欧阳倩雯 于 2019-11-07 设计创作，主要内容包括：本发明适用于化工领域,提供了一种漂白组合物及其制备方法和橄榄木材的漂白处理方法,该漂白组合物采用甲苯磺酸或者半胱氨酸作为漂白剂,并搭配分散剂和缓冲剂使用,相较于传统的双氧水漂白剂,漂白剂的使用量少,在该漂白组合物体系中的质量占比低于2%,且对人体皮肤等无刺激性,配方温和无毒,安全性高；此外,采用该漂白组合物对木材进行漂白处理,漂白稳定性好,不容易变褪色,漂白效果好,可满足使用者对木材白度的需求,具有良好的市场应用前景。(The invention is suitable for the chemical field, has provided a bleaching composition and its preparation method and bleaching processing method of the olive wood, this bleaching composition adopts toluenesulfonic acid or cysteine as bleaching agent, and use of dispersant and buffer in match, compared with traditional hydrogen peroxide solution bleaching agent, the consumption of bleaching agent is small, the mass ratio in this bleaching composition system is lower than 2%, and nonirritant to human skin, etc., the formulation is mild, non-toxic, the security is high; in addition, the bleaching composition is adopted to bleach wood, so that the bleaching stability is good, the wood is not easy to fade, the bleaching effect is good, the requirement of users on the whiteness of the wood can be met, and the bleaching composition has a good market application prospect.)

1. A bleaching composition is characterized by comprising the following components in parts by mass:

0.2 ~ 1.8.8% of bleaching agent, 0.5 ~ 1% of dispersing agent, 0.5 ~ 0.9.9% of buffering agent and the balance of deionized water;

wherein the bleaching agent is toluenesulfonic acid or cysteine.

2. The bleaching composition according to claim 1 wherein said bleaching agent is a 95% pure, 8 ~ 10% strength solution in toluene sulfonic acid.

3. The bleaching composition according to claim 1 wherein the bleaching agent is a 95% pure, 8.5 ~ 10% strength cysteine solution.

4. The bleaching composition of claim 1 wherein the dispersant is a sodium lauryl sulfate solution having a purity of 98% and a concentration of 9.5 ~ 10%.

5. The bleaching composition according to claim 1 wherein the buffering agent is sodium carbonate of 99% purity and 8 ~ 10% concentration, sodium bicarbonate of 98% purity and 9 ~ 10% concentration, or sodium silicate of 97% purity and 8.5 ~ 10% concentration, or a mixture of any combination thereof.

6. The bleaching composition according to claim 1, comprising the following components in parts by mass:

1.5% of bleaching agent, 0.5% of dispersing agent, 0.5% of buffering agent and the balance of deionized water.

7. A method of preparing a bleaching composition according to any one of claims 1 ~ 6, comprising the steps of:

weighing the components according to the formulation of the bleaching composition of any of claims 1 ~ 6;

and adding the bleaching agent, the dispersing agent and the buffering agent into the deionized water, and stirring for 4 ~ 6min at the temperature of 40 ~ 70 ℃ and the rotating speed of 1000 ~ 1500 rpm/min to obtain the bleaching composition.

8. A bleaching treatment method of olive wood is characterized by comprising the following steps:

the number of times the bleaching composition according to claim 7 is sprayed per part to be sprayed is determined according to the color of the part to be sprayed of the olive wood to be bleached, wherein the spraying amount per time is 123 ~ 220g/m²。

9. A bleaching treatment method of olive wood is characterized by comprising the following steps:

drying the cut olive wood to reduce the water content to below 15%;

placing the dried olive wood in a bleaching treatment vessel, adding the bleaching composition of claim 7 to the bleaching treatment vessel;

adjusting the pH of the wood bleaching composition in the bleaching treatment vessel to 7 ~ 9 and raising the temperature to 50 ~ 60 ℃ for 3 ~ 4 hours at a pressure of 0.1 ~ 0.25.25 MPa;

and after pressure relief, taking out the olive wood, and drying to constant weight to complete the bleaching treatment of the olive wood.

10. The method for bleaching olive wood according to claim 9, wherein the step of adjusting the pH of the bleaching composition in the bleaching container to 7 ~ 9, raising the temperature to 50 ~ 60 ℃, and maintaining the pressure at 0.1 ~ 0.25MPa for 3 ~ 4 hours is specifically:

the bleaching composition in the bleaching treatment vessel was adjusted to pH 8 and heated to 50 ℃ for 4 hours at a pressure of 0.15 MPa.

Technical Field

The invention belongs to the field of chemical industry, and particularly relates to a bleaching composition, a preparation method thereof and a bleaching treatment method of olive wood.

Background

With the increasing awareness of environmental protection, more and more people tend to return to green and environment-friendly living environment. The wood as a natural material is widely applied to the aspects of buildings, civil engineering, decoration, furniture and the like, and is closely related to the life of people.

The olive wood is a preferred raw material for producing various high-quality, high-positioning and high-requirement commodity wood parts due to high density, solid wood, bright color and clear and beautiful texture. As the olives belong to the tree species with large color difference, and the color of the newly processed wood surface is easy to generate various discoloring phenomena due to exposure in air or contact with light, heat, metal or acid-base substances, the value or use value of the raw materials, semi-finished products or finished products is seriously influenced. In addition, wood furniture has a high balance requirement on color, shape, structure and the like, and discolored wood cannot be well matched with indoor environment in many cases. In order to make the wood color uniform, it is necessary to bleach the wood before the surface finish treatment.

Most of the existing wood bleaches utilize high-concentration hydrogen peroxide (also called hydrogen peroxide) and ammonia water or chloride systems to bleach the surface of wood, wherein the bleaching effect of the hydrogen peroxide is better, but the concentration of the hydrogen peroxide is too low to achieve the bleaching effect, is too high to easily damage wood fibers, increases ineffective decomposition, and the high-concentration hydrogen peroxide (the concentration of the hydrogen peroxide reaches about 30 percent) is harmful to human bodies, stimulates respiratory mucosa, can cause human hair to turn yellow after long-term contact, has strong corrosivity and is inconvenient to transport, store and use. And the bleaching of the olive wood by using the bleaching agents still can not meet the whiteness requirement required by users.

Disclosure of Invention

The embodiment of the invention provides a bleaching composition, aiming at solving the problems that the bleaching effect of the existing wood bleaching agent on wood cannot meet the whiteness requirement required by a user and the safety is not high.

The embodiment of the invention is realized by that the bleaching composition comprises the following components in percentage by mass: 0.2-1.8% of bleaching agent, 0.5-1% of dispersing agent, 0.5-0.9% of buffering agent and the balance of deionized water; wherein the bleaching agent is toluenesulfonic acid or cysteine.

The embodiment of the invention also provides a preparation method of the bleaching composition, which comprises the following steps:

weighing the components according to the formula of the bleaching composition; and adding the bleaching agent, the dispersing agent and the buffering agent into the deionized water, and stirring for 4-6 hours at the temperature of 40-70 ℃ and the rotating speed of 1200-1500 rpm to obtain the bleaching composition.

The embodiment of the invention also provides a bleaching treatment method of olive wood, which comprises the following steps:

and determining the times of spraying the bleaching composition on each part to be sprayed according to the chromaticity of the part to be sprayed of the olive wood to be bleached, wherein the spraying amount is 123-220 g/m2 each time.

The embodiment of the invention also provides another bleaching treatment method of olive wood, which comprises the following steps:

drying the cut olive wood to reduce the water content to below 15%; putting dried olive wood into a bleaching treatment container, and adding the bleaching composition into the bleaching treatment container; adjusting the pH value of the wood bleaching composition in the bleaching treatment container to 7-9, heating to 50-60 ℃, and keeping for 3-4 hours under the pressure of 0.1-0.25 MPa; and after pressure relief, taking out the olive wood, and drying to constant weight to complete the bleaching treatment of the olive wood.

According to the bleaching composition provided by the embodiment of the invention, toluenesulfonic acid or cysteine is used as a bleaching agent, and a dispersing agent and a buffering agent are matched for use, compared with a traditional hydrogen peroxide bleaching agent, the usage amount of the bleaching agent is small, the mass ratio in a system of the bleaching composition is lower than 2%, and the bleaching composition has no irritation to human skin and the like, is mild and nontoxic in formula and is high in safety; in addition, the bleaching composition is adopted to bleach wood, so that the bleaching stability is good, the wood is not easy to fade, the bleaching effect is good, the requirement of users on the whiteness of the wood can be met, and the bleaching composition has a good market application prospect.

Detailed Description

In order to make the objects, technical solutions and advantages of the present invention more apparent, the present invention is further described in detail with reference to the following embodiments. It should be understood that the specific embodiments described herein are merely illustrative of the invention and are not intended to limit the invention.

According to the bleaching composition provided by the embodiment of the invention, toluenesulfonic acid or cysteine is used as a bleaching agent, and a dispersing agent and a buffering agent are matched for use, compared with a traditional hydrogen peroxide bleaching agent, the usage amount of the bleaching agent is small, the mass ratio in a system of the bleaching composition is lower than 2%, and the bleaching composition has no irritation to human skin and the like, is mild and nontoxic in formula and is high in safety; in addition, the bleaching composition is adopted to bleach wood, so that the bleaching stability is good, the wood is not easy to fade, the bleaching effect is good, the requirement of users on the whiteness of the wood can be met, and the bleaching composition has a good market application prospect.

The embodiment of the invention provides a bleaching composition which comprises the following components in percentage by mass: 0.2-1.8% of bleaching agent, 0.5-1% of dispersing agent, 0.5-0.9% of buffering agent and the balance of deionized water; wherein the bleaching agent is toluenesulfonic acid or cysteine.

Preferably, the bleaching agent is a toluenesulfonic acid solution with the purity of 95% and the concentration of 8-10%.

Preferably, the bleaching agent is a cysteine solution with the purity of 95% and the concentration of 8.5-10%.

Preferably, the dispersing agent is a sodium dodecyl sulfate solution with the purity of 98% and the concentration of 9.5-10%.

Preferably, the buffering agent is sodium carbonate with the purity of 99% and the concentration of 8-10%, sodium bicarbonate with the purity of 98% and the concentration of 9-10%, or sodium silicate with the purity of 97% and the concentration of 8.5-10%, or a mixture of any combination of the above.

In the embodiment of the invention, under the mutual cooperation of the bleaching agent with the concentration and the purity, the dispersing agent and the buffering agent, the bleaching effect is good, the treatment time period is short, the environmental pollution is small, and the bleaching cost is low.

Preferably, the bleaching composition comprises the following components in percentage by mass: 1.5% of bleaching agent, 0.5% of dispersing agent, 0.5% of buffering agent and the balance of deionized water.

The embodiment of the invention also provides a preparation method of the bleaching composition, which comprises the following steps:

weighing the components according to the formula of the bleaching composition; and adding the bleaching agent, the dispersing agent and the buffering agent into the deionized water, and stirring for 4-6 min under the conditions that the temperature is 40-70 ℃ and the rotating speed is 1000-1500 rpm, so as to obtain the bleaching composition.

In a preferred embodiment of the present invention, the bleaching agent, the dispersant and the buffering agent are added into the deionized water, and stirred for 5min at the temperature of 60 ℃, the pH value of 8 and the rotation speed of 1000 rpm, so as to obtain the bleaching composition.

The wood color is generated by two main reasons, namely that lignin contains C ═ C bonds and carbonyl groups (C ═ C)>C ═ O), vinyl (CH)₂CHR), hydroxyl (-OH), and methoxy (-OCH)₃) And carboxyl (-COOH) groups, which make the wood absorb visible light with certain wavelength to show certain color; secondly, the wood has extract, and the pigment, tannin and resin in the extract can make the wood colored. In addition, factors that affect wood discoloration and fading are light, enzymes, heat, oxygen, biological contamination (fungi), sources of chemical contamination (e.g., metals, acids, bases, etc.), and the like.

In the embodiment of the invention, toluenesulfonic acid or cysteine is used as an active ingredient of a bleaching agent, and the toluenesulfonic acid or the cysteine can react with a colored group such as tannic acid in wood to generate a colorless group under a certain alkaline condition, namely, the bleaching agent is used for destroying carbonyl and carbon atoms in a colored component of the woodBond between valence bonds and destruction of hydroxy (-OH), methoxy (-OCH)₃) And carboxyl and other color assisting groups to realize the purpose of bleaching.

The embodiment of the invention also provides a bleaching treatment method of olive wood, which comprises the following steps: determining the times of spraying the bleaching composition on each part to be sprayed according to the chromaticity of the part to be sprayed of the olive wood to be bleached, wherein the spraying amount is 123-220 g/m²。

In the embodiment of the present invention, the parts of the wood that need to be bleached are compared by using a color plate, and then the number of times and the spraying amount of the bleaching composition need to be sprayed to each part are determined according to the color shade comparison condition of each part of the wood. For example, the number of times and the amount of spraying may be increased as appropriate for darker portions, and the amount of spraying may be decreased for lighter portions.

As an exemplary embodiment of the present invention, for the olive wood having a darker wood color (for example, the whiteness of a dark portion is 20% to 25%), in order to make the whiteness of the dark portion to be 40%, 200g/m may be sprayed on the dark portion of the surface of the olive wood²And spraying once. For wood parts that are particularly dark, e.g., less than 10% of the original whiteness, the spray application can be repeated one or more times until the desired whiteness is achieved. This allows for flexibility in practical use.

For the dark parts, the bleaching agent can be sprayed and coated again for 2 to 3 hours after each time until the bleached parts reach the whiteness required by a user.

In the embodiment of the invention, when a product (part) with a particularly dark color needs to be bleached, the proportion of the buffering agent of the invention in the bleaching composition can be adjusted and increased so that the pH value of the bleaching composition system reaches 7-9, and is optimally 8, thereby ensuring the bleaching effect and efficiency.

The embodiment of the invention also provides another bleaching treatment method of olive wood, which comprises the following steps:

drying the cut olive wood to reduce the water content to below 15%; putting dried olive wood into a bleaching treatment container, and adding the bleaching composition into the bleaching treatment container; adjusting the pH value of the wood bleaching composition in the bleaching treatment container to 7-9, heating to 50-60 ℃, and keeping for 3-4 hours under the pressure of 0.1-0.25 MPa; and after pressure relief, taking out the olive wood, and drying to constant weight to complete the bleaching treatment of the olive wood.

Under the conditions of medium and alkaline, the bleaching composition in the bleaching treatment container is heated to 50-60 ℃ and pressurized to 0.1-0.25 MPa for treatment, so that the reaction efficiency of the bleaching agent and the chromophoric groups of the olive wood can be accelerated, the bleaching efficiency is improved, and an ideal bleaching effect can be obtained.

In a preferred embodiment of the present invention, the step of adjusting the pH of the bleaching composition in the bleaching treatment container to 7 to 9, raising the temperature to 50 to 60 ℃, and maintaining the bleaching composition under a pressure of 0.1 to 0.25MPa for 3 to 4 hours specifically comprises: the bleaching composition in the bleaching treatment vessel was adjusted to pH 8 and heated to 50 ℃ for 4 hours at a pressure of 0.15 MPa.

The technical effects of the technical solution of the present invention will be further described below by specific examples.