阅读说明：本技术 一种功能型抗冲击单板的制备方法 (Preparation method of functional impact-resistant veneer ) 是由 程明娟 张晓伟 王俊敏 杨楠 陈凯 刘爱军 沈惠文 鲁守余 张丽 于 2019-11-20 设计创作，主要内容包括：本发明公开了一种功能型抗冲击单板的制备方法,通过染色干燥-制备树脂-浸渍树脂-干燥平衡对单板进行加工,使单板具备良好持久的抗冲击性和美观性,延长其使用寿命。具体是通过控制工艺过程单板的含水率,避免开裂,翘曲变形等问题,使单板自身强度得到保持,在此基础上通过在单板上涂覆以改性PAE为主要原料的改性树脂,结合真空浸渍工艺,提高单板的抗冲击强度、尺寸稳定性和防水性；采用阻胺类光稳定剂和双偶氮酸性染料组成的特定复配染料结合立式浸染工艺,使染色效果美观且持久,同时改性树脂隔绝环境,进一步提升单板的色牢度。(The invention discloses a preparation method of a functional impact-resistant veneer, which is characterized in that the veneer is processed through dyeing and drying, resin preparation, resin impregnation and drying balance, so that the veneer has good and lasting impact resistance and aesthetic property, and the service life of the veneer is prolonged. The method specifically comprises the steps of controlling the water content of the single board in the process, avoiding the problems of cracking, warping deformation and the like, keeping the strength of the single board, coating modified resin taking modified PAE as a main raw material on the single board, and improving the impact strength, the dimensional stability and the water resistance of the single board by combining a vacuum impregnation process; the special compound dye consisting of the amine-resistant light stabilizer and the disazo acid dye is combined with a vertical dip dyeing process, so that the dyeing effect is attractive and durable, and meanwhile, the modified resin isolates the environment, and the color fastness of the veneer is further improved.)

1. A preparation method of a functional impact-resistant veneer is characterized by comprising the following steps:

(1) taking a wood veneer as a raw material, dyeing the veneer, and drying to reduce the water content to below 10% to obtain a veneer A;

(2) dispersing hindered amine light stabilizer, antibacterial agent and tourmaline powder in environment-friendly reinforced resin to prepare modified resin;

(3) treating the veneer A with the modified resin prepared in the step (2), and preparing a veneer B by adopting a vacuum pressurization impregnation process;

(4) and (5) drying the veneer B step by step to balance the water content to 6-12%, and cutting according to the required size to obtain a functional impact-resistant veneer finished product.

2. The method for preparing a functional impact-resistant veneer according to claim 1, wherein the method comprises the following steps: the dyeing process in the step (1) is a vertical dip dyeing process, and the process flow is as follows: dissolving the dye at 65-70 ℃, simultaneously starting an air pump, introducing air into the dye liquor, stirring the dye liquor to make the concentration of the dye liquor uniform, and dissolving the dye for 40-60 min; vertically immersing the wood veneer into a dye liquor in a bath ratio of V liquor: and (3) heating the V board = (8-15): 1 at the speed of 1-3 ℃/min, heating to 90-95 ℃ for heat preservation dyeing, and carrying out dip dyeing on the wood veneer for 4-12 h.

3. The method for preparing a functional impact-resistant veneer according to claim 1, wherein the method comprises the following steps: the dyeing treatment in the step (1) adopts hindered amine light stabilizer and acid dye according to the mass ratio of (15-30): (100-300) and preparing the acid binary compound dye.

4. The method for preparing a functional impact-resistant veneer according to claim 3, wherein the method comprises the following steps: the acid dye is a disazo acid dye.

5. The method for preparing a functional impact-resistant veneer according to claim 1, wherein the method comprises the following steps: and (2) adopting a roller dryer or a mesh belt dryer for the drying process in the step (1), wherein the drying temperature is 60-100 ℃, and the drying time is 30-45 min.

6. The method for preparing a functional impact-resistant veneer according to claim 1, wherein the method comprises the following steps: the environment-friendly reinforced resin in the step (2) is modified PAE, and the content of the modified PAE in the modified resin is 80-95 wt%.

7. The method for preparing a functional impact-resistant veneer according to claim 1, wherein the method comprises the following steps: the vacuum pressurizing impregnation process in the step (3) has the vacuum degree of-0.08 to-0.1 MPa, the vacuum time of 30 to 60min, the pressurizing pressure of 0.5 to 1.5MPa and the pressurizing time of 4 to 6 hours.

8. The method for preparing a functional impact-resistant veneer according to claim 1, wherein the method comprises the following steps: the step-by-step drying process flow in the step (4) is as follows: the moisture content of the veneer is reduced to 18% -28% through a roller dryer, then the veneer enters a vacuum drying kiln to reduce the moisture content to 8% -15%, and finally the veneer enters a curing room to balance the moisture content to 6% -12%.

9. The method for preparing a functional impact-resistant veneer according to claim 1, wherein the method comprises the following steps: the wood veneer is a sliced or sawed wood veneer.

Technical Field

The invention belongs to the technical field of wood processing, and relates to a preparation method of a functional impact-resistant veneer.

Background

Along with the improvement of science and technology and the continuous improvement of living standard of people, people have higher and higher requirements on the appearance and the quality of the floor, and the high impact resistance, the comfort and the beauty become necessary performances of floor materials, while the solid wood composite floor has the characteristics of natural patterns, comfortable foot feeling, safe use and the like, and becomes a mainstream product of the current decorative floor materials due to good comprehensive performance. The solid wood composite floor is formed by laminating single boards, the single boards are generally reprocessed in order to improve the using effect of the solid wood composite floor, most commonly, the colors are enriched while natural wood grains are kept through dyeing, the visual effect is greatly improved, and the impact resistance level is improved through surface gluing.

To make the single board have good impact resistance, on one hand, the single board has good strength and dimensional stability, and on the other hand, the impact resistance is improved by gluing. However, in the processing processes of dyeing, gluing and the like, due to the change of internal water content and external conditions (such as temperature and pressure), the internal stress of the veneer can be changed or generate large difference, the problems of cracking, warping deformation and the like are easily caused, the impact strength and the dimensional stability of the veneer are obviously poor, and the production or the use of the floor are directly influenced. The gluing effect depends on the performance and quality of glue solution and whether the combination of the glue solution and the veneer is stable and firm, and the formaldehyde-containing synthetic resin is wear-resistant, waterproof and good in viscosity, and is often used as the glue solution, such as urea-formaldehyde resin and melamine-formaldehyde resin, and the use of the resin has low environmental protection level and single function.

The dyeing effect of the floor is represented by coloring uniformity and durability, and many dyed floors are easy to fade after long-term use and seriously affect the appearance, the fading of the floor is mainly caused by that ① under the irradiation of light (especially ultraviolet light), a color system of dye molecules is changed or damaged, so that the dye is decomposed to generate a color change or fading phenomenon, ② environmental factors cause fast fading, and the photo-oxidation process is accelerated by full contact of high temperature, high humidity and oxygen, so that the fading is more serious, ③ dye has poor fixation rate and is easy to separate from a plate under the action of external force.

Therefore, how to process the veneer without damaging the strength and structure of the veneer and enabling the veneer to have good and durable impact resistance and aesthetic property becomes a problem to be solved urgently.

Disclosure of Invention

Aiming at the problems, the invention provides a preparation method of a functional impact-resistant veneer, which has the excellent performances of impact resistance, gorgeous color, high color fastness, low formaldehyde release amount and the like, and also has the functions of antibiosis and anion release, and long service life.

In order to achieve the purpose, the invention adopts the following specific technical scheme:

a preparation method of a functional impact-resistant veneer comprises the following steps:

(1) taking a wood veneer as a raw material, dyeing the veneer, and drying to reduce the water content to below 10% to obtain a veneer A;

(2) dispersing hindered amine light stabilizer, antibacterial agent and tourmaline powder in environment-friendly reinforced resin to prepare modified resin;

(3) treating the veneer A with the modified resin prepared in the step (2), and preparing a veneer B by adopting a vacuum pressurization impregnation process;

(4) and (5) drying the veneer B step by step to balance the water content to 6-12%, and cutting according to the required size to obtain a functional impact-resistant veneer finished product.

Preferably, the dyeing process in the step (1) is a vertical dip dyeing process, and the process flow is as follows: dissolving the dye at 65-70 ℃, simultaneously starting an air pump, introducing air into the dye liquor, stirring the dye liquor to make the concentration of the dye liquor uniform, and dissolving the dye for 40-60 min; vertically immersing the wood veneer into a dye liquor in a bath ratio of V liquor: and (3) heating the V board = (8-15): 1 at the speed of 1-3 ℃/min, heating to 90-95 ℃ for heat preservation dyeing, and carrying out dip dyeing on the wood veneer for 4-12 h.

Preferably, the dyeing treatment in the step (1) adopts hindered amine light stabilizer and acid dye according to the mass ratio of (15-30): (100-300) and preparing the acid binary compound dye.

Further, the acid dye is a disazo acid dye, the molecular weight of the disazo acid dye is 500-600 daltons, and the molecular formula of the disazo acid dye is C₂₄H₂₂N₄O₆S₂。

Preferably, the drying process in the step (1) adopts a roller dryer or a mesh belt dryer, the drying temperature is 60-100 ℃, and the drying time is 30-45 min. The moisture content of the veneer is reduced to below 10% by the process, and the warpage and deformation degree of the dried veneer is low while the drying efficiency is ensured.

Preferably, the environment-friendly reinforced resin in the step (2) is modified PAE, and the content of the modified PAE in the modified resin is 80-95 wt%. The PAE is polyamide epichlorohydrin resin, has high strength and good viscosity, and the modified PAE reduces hydrophilic groups through chemical modification on the basis of the PAE, thereby improving the water resistance. Preferably, the vacuum pressure impregnation process in the step (3) has a vacuum degree of-0.08 to-0.1 MPa, a vacuum time of 30 to 60min, a pressure of 0.5 to 1.5MPa and a pressure time of 4 to 6 h. The vacuum degree and the pressurizing pressure are too large during impregnation, the equipment development cost is increased unnecessarily, and the quality and the performance of the veneer are not improved; too short or too long vacuum time and pressurization time can affect the performance of the veneer, and indexes such as impact resistance, color fastness, negative ion release amount and the like can not meet the requirements.

Preferably, the step-by-step drying process flow in the step (4) is as follows: the moisture content of the veneer is reduced to 18% -28% through a roller dryer, then the veneer enters a vacuum drying kiln to reduce the moisture content to 8% -15%, and finally the veneer enters a curing room to balance the moisture content to 6% -12%. The veneer dried by the process has flat surface, less cracking and high comprehensive drying efficiency.

Preferably, the wood veneer is a sliced or sawn wood veneer. The tree species can be maple, oak, rubber wood, poplar, eucalyptus, etc.

The single board is processed through dyeing and drying, resin preparation, resin impregnation and drying balance, and the performance of the single board is improved. In order to enhance the impact resistance of the veneer, the change of the structure and the strength of the veneer is firstly reduced by controlling the moisture content of the veneer, the moisture content of the veneer is reduced to below 10% through drying after dyeing, the moisture content of the veneer is balanced to 6-12% through step-by-step drying in the drying balancing process, the moisture content of the veneer is controlled through the two drying processes, excessive expansion after dyeing and resin impregnation is avoided, particularly the step-by-step drying process, the moisture content is slowly reduced through three stages to be balanced, the problems of cracking, warping deformation and the like of the veneer caused by overlarge moisture content difference of different parts or large change of the moisture content of the same part in a short time in the drying process can be effectively avoided, the change of internal stress is reduced, the veneer surface is flat, and the strength of the veneer is well maintained. On the basis, the modified resin is selected as the coating glue to improve the impact strength of the veneer, the modified resin takes the modified PAE as the main raw material, does not contain formaldehyde, has less total volatile organic compounds, has good environmental protection, and has high strength, good waterproofness and viscosity, and the modified resin can be firmly combined with the veneer through the control of the process conditions of the vacuum pressurization impregnation process, so that the impact strength, the dimensional stability and the waterproofness of the veneer are effectively improved. In addition, the modified resin is added with hindered amine light stabilizer, antibacterial agent and tourmaline powder, so that the single board has the functions of light resistance, antibacterial and anion release.

① is dyed by acid binary compound dye prepared by hindered amine light stabilizer and acid dye according to proportion, wherein the acid dye is disazo acid dye with rich color and can effectively improve single board visual effect, the hindered amine light stabilizer captures alkyl free radical generated in photolysis, decomposes peroxide accumulated by photooxidation and quenches singlet oxygen which can cause photodegradation, thereby effectively preventing dye degradation, ② is dyed by vertical dip dyeing process, the dye uptake is improved by stage temperature rise and air stirring, the dye is uniformly distributed in the single board, thereby effectively improving the uniformity of color distribution and the fixation rate of the dye, and fully and durably playing the function of the dye, ③ is coated on the single board modified resin, thereby not only improving the impact strength of the single board, but also effectively isolating the environment, avoiding the influence of the change of factors such as temperature, humidity and oxygen on the dye, and the hindered amine light stabilizer is added in the dye and the modified resin, and the single board is not easy to fade by the combined action of the hindered amine light stabilizer in the dye, and the light fastness is obviously improved.

In conclusion, the invention has the following beneficial effects:

1. the change of the structure and the strength of the veneer is reduced by controlling the water content of the veneer in the process, particularly, the water content of the veneer is controlled by drying the veneer after dyeing and drying the veneer step by step after resin impregnation, so that the excessive expansion of the veneer is avoided, particularly, the water content is slowly reduced in three stages and finally balanced, the problems of cracking, warping deformation and the like of the veneer are effectively avoided, the change of internal stress is reduced, the surface of the veneer is flat, and the strength of the veneer is well maintained.

2. On the basis of ensuring the strength of the veneer, the impact strength of the veneer is improved by coating the modified resin on the veneer, the modified resin takes modified PAE as a main raw material, does not contain formaldehyde, has good environmental protection performance, high strength, good waterproofness and viscosity, and the modified resin is firmly combined with the veneer by combining a vacuum pressurization impregnation process, so that the impact strength, the dimensional stability and the waterproofness of the veneer are obviously improved. The impact strength of the treated veneer is improved by about 20 percent, and the water absorption thickness expansion rate is reduced by about 50 percent. In addition, hindered amine light stabilizer, antibacterial agent and tourmaline powder are added into the modified resin, so that the veneer has the functions of light resistance, antibiosis and anion release.

3. The specific compound dye consisting of the amine-resistant light stabilizer and the disazo acid dye is adopted, so that the visual effect of the veneer is improved, and the photodegradation of the dye is prevented; the vertical dip dyeing process is adopted for coloring, so that the distribution uniformity and fixation rate of the dye are improved, and the dyeing effect is attractive and lasting; and the modified resin is coated on the veneer to avoid the influence of the change of environmental factors such as temperature, humidity, oxygen and the like on the dye, and the hindered amine light stabilizer added in the modified resin and the hindered amine light stabilizer in the dye act together to remarkably improve the color fastness of the veneer, and the color fastness of the veneer can be kept to be more than 5 grades.

Detailed Description

The present invention will be further described with reference to the following examples.