阅读说明：本技术 一种高温热处理板材及其降醛工艺 (High-temperature heat treatment plate and aldehyde reduction process thereof ) 是由 张焕兵 叶昌海 于 2020-04-29 设计创作，主要内容包括：本发明属于人造板加工技术领域,提供了一种高温热处理板材及其降醛工艺。该高温热处理板材降醛工艺包括：(1)将平衡层浸胶后,与基材进行第一次热压得到第一板材层；对第一板材层进行第一次温控除醛；(2)将装饰层浸胶后,与第一板材层进行第二次热压得到第二板材层；对第二板材层进行第二次温控除醛；(3)将耐磨层浸胶后,与第二板材层进行第三次热压得到第三板材层；对第三板材层进行第三次温控除醛。该高温热处理板材降醛工艺具有优异的除醛效果,且具有良好的节能效果,所制得的高温热处理板材的含醛率低,能够达到E0级,绿色环保。(The invention belongs to the technical field of artificial board processing, and provides a high-temperature heat treatment board and an aldehyde reduction process thereof. The high-temperature heat treatment plate aldehyde reduction process comprises the following steps: (1) after gum dipping of the balance layer, carrying out first hot pressing on the balance layer and the base material to obtain a first plate layer; performing first temperature control and aldehyde removal on the first plate layer; (2) after the decorative layer is dipped, carrying out secondary hot pressing on the decorative layer and the first plate layer to obtain a second plate layer; performing secondary temperature control and aldehyde removal on the second plate layer; (3) after the wear-resistant layer is dipped, carrying out third hot pressing on the wear-resistant layer and the second plate layer to obtain a third plate layer; and carrying out third temperature control aldehyde removal on the third plate layer. The aldehyde reduction process for the high-temperature heat treatment plate has an excellent aldehyde removal effect and a good energy-saving effect, and the prepared high-temperature heat treatment plate is low in aldehyde content, can reach E0 level, and is green and environment-friendly.)

1. The high-temperature heat treatment plate aldehyde reduction process is characterized by comprising the following steps: the method comprises the following steps: (1) after gum dipping of the balance layer, carrying out first hot pressing on the balance layer and the base material to obtain a first plate layer; then, performing first temperature control aldehyde removal on the first plate layer; (2) after the decorative layer is dipped, carrying out secondary hot pressing on the decorative layer and the first plate layer to obtain a second plate layer; then, performing secondary temperature control and aldehyde removal on the second plate; (3) after the wear-resistant layer is dipped, carrying out third hot pressing on the wear-resistant layer and the second plate layer to obtain a third plate layer; and then carrying out third temperature control aldehyde removal on the third plate.

2. The high-temperature heat treatment plate aldehyde reduction process according to claim 1, characterized in that:

the first temperature control aldehyde removal in the step (1) comprises the following steps: the first plate layer sequentially passes through a preheating section, an aldehyde reducing section and a cooling section of the heat treatment kiln; the temperature of the preheating section is 90-100 ℃, and the first plate layer stays for 20-30 min; the temperature of the aldehyde reduction section is 110-120 ℃, and the first plate layer stays for 30-40 min;

the second temperature-controlled aldehyde removal in the step (2) comprises the following steps: the second plate layer sequentially passes through the preheating section, the aldehyde reducing section and the cooling section; the temperature of the preheating section is 100-110 ℃, and the second plate layer stays for 20-30 min; the temperature of the aldehyde reduction section is 120-130 ℃, and the second plate layer stays for 30-40 min;

the third temperature-controlled aldehyde removal in the step (3) comprises the following steps: the third plate layer sequentially passes through the preheating section, the aldehyde reducing section and the cooling section; the temperature of the preheating section is 110-120 ℃, and the third plate layer stays for 20-30 min; the temperature of the aldehyde reduction section is 130-140 ℃, and the third plate layer stays for 30-40 min.

3. The high-temperature heat treatment plate aldehyde reduction process according to claim 2, characterized in that: in the step (1), the heat of the preheating section is derived from the waste heat of the first hot pressing and the cooling section; in the step (2), the heat of the preheating section is derived from the waste heat of the second hot pressing and the cooling section; in the step (3), the heat of the preheating section comes from the residual heat of the third hot pressing and the cooling section.

4. The high-temperature heat treatment plate aldehyde reduction process according to claim 1, characterized in that: in the step (1), the pressure of the first hot pressing is 2.5-2.8Mpa, the temperature is 150-160 ℃, and the first plate layer is hot pressed until the water content of the first plate layer is 10-12%.

5. The high-temperature heat treatment plate aldehyde reduction process according to claim 2, characterized in that: in the step (1), the temperature of the cooling section is 50-60 ℃, and the first plate layer stays in the cooling section for 20-30 min.

6. The high-temperature heat treatment plate aldehyde reduction process according to claim 1, characterized in that: in the step (2), the pressure of the second hot pressing is 2.8-3.2Mpa, the temperature is 160-170 ℃, and the second plate layer is hot pressed until the water content of the second plate layer is 8-10%.

7. The high-temperature heat treatment plate aldehyde reduction process according to claim 2, characterized in that: in the step (2), the temperature of the cooling section is 60-70 ℃, and the second plate layer stays in the cooling section for 20-30 min.

8. The high-temperature heat treatment plate aldehyde reduction process according to claim 1, characterized in that: in the step (3), the pressure of the third hot pressing is 3.2-3.6Mpa, the temperature is 170-.

9. The high-temperature heat treatment plate aldehyde reduction process according to claim 2, characterized in that: in the step (3), the temperature of the cooling section is 70-80 ℃, and the third plate layer stays in the cooling section for 20-30 min.

10. A high-temperature heat treatment plate is characterized in that: the high-temperature heat-treated plate aldehyde-reducing process is prepared by adopting the high-temperature heat-treated plate aldehyde-reducing process as claimed in any one of claims 1 to 9.

Technical Field

The invention belongs to the technical field of artificial board processing, and particularly relates to a high-temperature heat treatment board and an aldehyde reduction process thereof.

Background

The construction of composite floors usually comprises a wear layer, a decorative layer, a substrate and a balancing layer. The four layers are glued together by hot pressing. The wear-resistant layer, the decorative layer and the balance layer are all gummed paper, wherein the base material is a high-density fiberboard.

The production of a composite floor usually comprises the following steps in sequence: dipping, hot pressing, plate sawing, curing and grooving. The glue dipping can block gaps of paper, the pressing cannot cause quality problems such as pinholes, whitening, white spots, foaming and the like due to air entering, and meanwhile, the surface gluing strength can be increased. However, the glue used in the impregnation step is specially formulated, and is generally a melamine-formaldehyde resin. The formaldehyde contained in the composite floor can be slowly released in the using process of the composite floor, and the health is endangered.

Patent document No. CN109249503A discloses a numerical control device for reducing formaldehyde in high-temperature heat-treated sheet material and a method for removing formaldehyde, which removes formaldehyde from sheet material by continuous heating. However, since the board is made of a plurality of layers of adhesive, it is very difficult to completely release formaldehyde from the board substrate and formaldehyde in the glue even when the formaldehyde is removed by heating.

Disclosure of Invention

In view of the above-mentioned disadvantages in the prior art, a first object of the present invention is to provide a high temperature heat treatment plate aldehyde-reducing process. The high-temperature heat treatment plate formaldehyde-reducing process has an excellent formaldehyde-removing effect, and can almost completely remove formaldehyde in the base material and glue.

In view of the above-mentioned disadvantages of the prior art, a second object of the present invention is to provide a high temperature heat-treated plate. The aldehyde content of the board is low, and the board can reach E0 level and is green and environment-friendly.

In order to achieve the above purpose, the solution adopted by the invention is as follows:

a high-temperature heat treatment plate aldehyde reduction process comprises the following steps: (1) after gum dipping of the balance layer, carrying out first hot pressing on the balance layer and the base material to obtain a first plate layer; then, performing first temperature control and aldehyde removal on the first plate layer; (2) after the decorative layer is dipped, carrying out secondary hot pressing on the decorative layer and the first plate layer to obtain a second plate layer; then, performing secondary temperature control and aldehyde removal on the second plate; (3) after the wear-resistant layer is dipped, carrying out third hot pressing on the wear-resistant layer and the second plate layer to obtain a third plate layer; and then carrying out third temperature control aldehyde removal on the third plate.

A high-temperature heat treatment plate is prepared by adopting the high-temperature heat treatment plate aldehyde reduction process.

The high-temperature heat treatment plate and the aldehyde reduction process thereof provided by the invention have the beneficial effects that: the high-temperature heat treatment plate aldehyde reduction process comprises the steps of firstly carrying out hot pressing on a balance layer and a base material, and then controlling the temperature to remove aldehyde so as to remove formaldehyde contained in the base material and formaldehyde in an adhesive between the base material and the balance layer; performing hot pressing with the decorative layer, and controlling the temperature to remove formaldehyde so as to remove formaldehyde in the adhesive between the balance layer and the decorative layer, and further remove formaldehyde in the adhesive between the base material and the balance layer which is not removed in the step (1) and formaldehyde in the base material; and (3) performing hot pressing on the decorative layer and the wear-resistant layer, and then performing temperature control to remove formaldehyde so as to remove formaldehyde in the adhesive between the decorative layer and the wear-resistant layer and formaldehyde which is not removed in the step (2). In this application, remove the aldehyde through carrying on once gluing after immediately, compare in removing the aldehyde again after gluing layer upon layer at panel, remove the aldehyde more thoroughly, avoid removing the aldehyde inadequately to panel inside.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly and completely described below. The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available commercially.

The method for reducing aldehyde in the high-temperature heat-treated plate provided by the embodiment of the invention is specifically described below.

A high-temperature heat treatment plate aldehyde reduction process comprises the following steps: (1) and after gum dipping of the balance layer, carrying out first hot pressing on the balance layer and the base material to obtain a first plate layer. Wherein, the pressure of the first hot pressing is 2.5-2.8Mpa, the temperature is 150-. In this embodiment, it should be noted that the control of the water content of the first sheet material layer is achieved by adjusting the hot pressing time, and the hot pressing time required for different water contents is different. The balance layer and the base material can be fully glued together through the hot pressing process.

And then carrying out first temperature control aldehyde removal on the first plate layer. The first temperature-controlled aldehyde removal comprises the following steps: the layers sequentially pass through a preheating section, an aldehyde reducing section and a cooling section of a heat treatment kiln; wherein the heat of the preheating section is from the waste heat of the first hot pressing and the waste heat of the cooling section.

In this embodiment, since the temperature of the hot pressing is higher than the aldehyde removal temperature, the use of the waste heat of the hot pressing as the heat of the preheating section can play a role in energy conservation and emission reduction. Meanwhile, the waste heat of the cooling section is conveyed to the preheating section to be used as partial heat of the preheating section, so that the plate of the preheating section has certain initial temperature, the heat load of the aldehyde reducing treatment section is further reduced, and the aim of energy-saving heat treatment is fulfilled. The waste heat of the cooling section is the heat generated by the heat exchange of the first plate in the cooling section due to the drop of the external temperature.

In the production process, the air flow of the cooling section and the preheating section adopts closed circulation to basically realize cold inlet and cold outlet, and the heat pollution to the environment can be further reduced while the energy-saving target is achieved.

In the embodiment, the temperature of the preheating section is 70-80 ℃, and the first plate layer stays for 20-30 min; the temperature of the aldehyde reduction section is 110-120 ℃, and the first plate layer stays for 30-40 min; the temperature of the cooling section is 50-60 ℃, and the first plate layer stays for 20-30 min.

(2) And after the decorative layer is dipped in glue, carrying out secondary hot pressing on the decorative layer and the first plate layer to obtain a second plate layer. Wherein the pressure of the second hot pressing is 2.8-3.2Mpa, the temperature is 160-170 ℃, and the second plate layer is hot pressed until the water content of the second plate layer is 8-10%. The decorative layer and the base material can be fully glued together through the hot pressing process.

And then carrying out secondary temperature control aldehyde removal on the second plate layer. The second temperature-controlled aldehyde removal comprises the following steps: the second plate layer sequentially passes through a preheating section, an aldehyde reducing section and a cooling section; the heat of the preheating section is from the waste heat of the second hot pressing and cooling section; the temperature of the preheating section is 80-90 ℃, and the second plate layer stays for 20-30 min; the temperature of the aldehyde reduction section is 120-130 ℃, and the second plate layer stays for 30-40 min; the temperature of the cooling section is 60-70 ℃, and the second plate layer stays for 20-30 min.

(3) And after the wear-resistant layer is dipped, carrying out third hot pressing on the wear-resistant layer and the second plate layer to obtain a third plate layer. Wherein the pressure of the third hot pressing is 3.2-3.6Mpa, the temperature is 170-180 ℃, and the third hot pressing is carried out until the water content of the third plate layer is 6-8%. The wear-resistant layer and the decorative layer can be fully glued together through the hot pressing process.

And then carrying out third temperature control aldehyde removal on the third plate layer. The third temperature-controlled aldehyde removal comprises the following steps: the third plate layer sequentially passes through a preheating section, an aldehyde reducing section and a cooling section; the heat of the preheating section is the waste heat of the third hot pressing and cooling section; the temperature of the preheating section is 90-100 ℃, and the third plate layer stays for 20-30 min; the temperature of the aldehyde reduction section is 130-140 ℃, and the third plate layer stays for 30-40 min; the temperature of the cooling section is 70-80 ℃, and the third plate layer stays for 20-30 min.

In each temperature control and aldehyde removal process, a curve temperature control mode of preheating, aldehyde reduction and cooling is adopted; the preheating section can play a transition role, so that the plate has a certain initial temperature, the heat load of the formaldehyde reducing section is reduced, formaldehyde molecules are gradually released from the plate and the adhesive along with the gradual rise of the temperature, and the aim of removing formaldehyde is fulfilled.

In addition, along with the gradual increase of the thickness of the plate, the temperature of each formaldehyde reduction section is increased so as to meet the requirement that formaldehyde at different depth positions of the plate can move at an accelerated speed in the heat treatment stage, and the release of free formaldehyde left in the plate to the outside is promoted.

The embodiment of the invention also provides a high-temperature heat treatment plate which is prepared by adopting the high-temperature heat treatment plate aldehyde reduction process.

The features and properties of the present invention are described in further detail below with reference to examples.