CN112848608A

CN112848608A - Novel plate warping prevention process

Info

Publication number: CN112848608A
Application number: CN202110061852.1A
Authority: CN
Inventors: 李哲; 曹长林
Original assignee: Sky Win Technology Co ltd; Fujian Normal University
Current assignee: Sky Win Technology Co ltd; Fujian Normal University
Priority date: 2021-01-18
Filing date: 2021-01-18
Publication date: 2021-05-28

Abstract

The invention discloses a novel plate warping prevention process, belongs to the technical field of decorative plate processing processes, and comprises the following steps: in the process of cooling and solidifying the base material, the shrinkage allowance is reserved downwards in advance, and reverse buckling deformation is reserved in the moment of attaching the wrapper to the base material plate, so that the problem of product buckling is solved. The purposes of reducing production procedures, reducing energy consumption and saving cost are achieved.

Description

Novel plate warping prevention process

Technical Field

The invention belongs to the technical field of decorative plate processing technologies, and particularly relates to a novel plate warping prevention technology.

Background

WPC, halogen-free board, LVT and SPC floor are all novel decorative floor on the market in recent years. The main raw materials are polyvinyl chloride, calcium powder and the like. The floor is light, thin, wear-resistant, good in elasticity, fireproof, flame-retardant, water-absorbing, moisture-proof, sound-absorbing and noise-preventing, and is particularly simple, convenient and pollution-free in installation. Through development of few years, the technology has been developed from the single marble-imitated effect for manufacturing hard floors to the manufacturing of various soft and hard floors with various wall thicknesses, wood-proof floors, foamed light floors, environment-friendly methane-free plastic wood grain floors and the like. Has been generally accepted in large and medium cities at home and abroad, and has wide application.

The process of floor production can be summarized as follows: the mixed plastic material is heated and sheared to reach flow state and has excellent plasticity, referred to as plasticizing. And then the sheet-shaped substrate is formed and extruded by a die, and is cooled and formed by related equipment, such as a calender or a forming plate, under the condition of hot state. Meanwhile, the face is covered with a face skin (the face skin consists of a wear-resistant layer, a color film, an LVT backing material and the like). And performing wear-resistant protection treatment on the surface of the UV paint coating production line. And then the substrate is subjected to the sectional slotting treatment by a slotting machine, and finally the finished product is packed.

Because the substrate is amorphous, it has no fixed shape and a fixed melting point, and is isotropic. The product is softened gradually during heating, and enters a plastic state and a high-viscosity state from a brittle state to a melt, and the viscosity is continuously changed. Melting and solidification are reversible. We can view the substrate in its unsolidified state as a solid state that retains glass-like properties, i.e., a glassy state.

The shape of the substrate changes under the influence of a slight external force during the cooling of the substrate. Floor conforming is the process of conforming while the substrate is in a plastic state (solid melt) and then cooling down to gradually enter the glass state. In the cooling process of the base material, because the peripheral cooling speed is higher than the intermediate cooling speed, a temperature drop difference is generated, and meanwhile, the material of the wrapper attached to the upper surface of the base material is different from that of the base material, and the shrinkage rate during cooling is also different (the shrinkage rate of the wrapper is greater than that of the base material). Therefore, the finished plate can be warped upwards around after being cooled to normal temperature, and the use and the appearance are affected. Although the hot-pressing laminating process of the SPC floor and the cold-pressing laminating process of the WPC floor meet the national standards, the WPC floor still has slight deformation and warpage, and the grade and the attractiveness of products are affected.

In order to solve the warpage problem, the prior art generally attaches bottom skins such as a silencing pad (XPE material), a wear-resistant layer or an LVT layer on the back surface of a substrate, so that the balance and the stability of the substrate reach the best state. The existing process has the disadvantages of complicated procedures, high processing cost and high energy consumption. Is not beneficial to the sustainable development of the industry.

Disclosure of Invention

The invention aims to solve the technical problems of easy warpage and poor product performance in the cooling process of a plate in the prior art, and provides a method and a novel plate warpage prevention process which are simple and do not influence the product performance.

The novel plate warping prevention process is characterized by comprising the following steps: and in the process of cooling and solidifying the base material, reserving shrinkage allowance downwards in advance.

Preferably, the method for reserving the shrinkage allowance downwards in advance is to manufacture a structure so that the prefabricated plate is bent downwards to be approximately spherical.

Preferably, the method comprises the following steps: and placing the plate in the structure with the downward bending direction for cooling and solidification.

Preferably, the downward curvature of the structure during cooling varies as the shape of the sheet changes during cooling.

By adopting the technical means, the technical effects are as follows:

in the process of cooling and solidifying the base material from the glass state, the invention reserves shrinkage allowance downwards in advance, thereby solving the problem of product warpage and achieving the purposes of reducing production procedures, reducing energy consumption and saving cost.

Drawings

FIG. 1 is a schematic view of the structure of the plate material in the example;

FIG. 2 is a schematic view showing a warping direction of a sheet prepared by a conventional process;

FIG. 3 is a schematic structural view of the substrate with a reserved reverse buckling deformation amount before the lamination of the wrapper;

FIG. 4 is a schematic structural view of a product after cooling and forming;

in the figure: 1. a substrate board; 2. grid cloth or glass fiber borers; 3. an LVT layer; 4. PVT color film layer; 5. a transparent sheet wear layer; 6. a sound damping pad or a transparent sheet abrasion resistant layer.

Detailed Description

The following detailed description of the embodiments of the present invention is provided in conjunction with the accompanying drawings, and is not intended to limit the scope of the invention. It is to be understood that in the description of the present invention, the terms "front", "back", "left", "right", "up", "down", and the like, indicate orientations or positional relationships based on the orientations or positional relationships shown in the drawings, and are only for convenience in describing the present invention and simplifying the description, but do not indicate or imply that the referred device or element must have a specific orientation, be constructed in a specific orientation, and be operated. The shapes, colors and patterns in the drawings are only used for convenience of description or for better showing of the layered structure of the existing common boards, and do not indicate or imply that the process of the invention is only suitable for boards with the layers or materials as shown in the drawings. And therefore should not be construed as limiting the invention.

The novel plate warping prevention process is characterized by comprising the following steps: and in the process of cooling and solidifying the base material, reserving shrinkage allowance downwards in advance. The method for reserving shrinkage allowance downwards in advance is to manufacture a structure so that a plate prepared in advance is bent downwards to be approximately spherical, and comprises the following steps: and placing the plate in the structure with the downward bending direction for cooling and solidification. The downward curvature of the structure during cooling varies with the shape of the sheet as it cools.

Fig. 1 is the schematic diagram of the structure of the existing plate, the surface of the substrate 1 is covered with a skin, the skin is sequentially a mesh cloth or a glass fiber 2, a LVT layer 3, a PVC color film layer 4 and a transparent sheet wear layer 5 from inside to outside, in order to solve the problem of plate warping, a mute pad or a transparent sheet wear layer 5 is attached to the back of the substrate 1, or bottom skins such as a LVT layer are attached to the back of the substrate, wherein the mute pad is made of XPE material, so that the balance and stability of the mute pad reach the best state.

As shown in fig. 2, the warpage direction of the existing three-layer board (or multi-layer board); as shown in fig. 3, the direction of the reserved reverse buckling deformation amount is performed at the instant when the base material plate is attached to the wrapper; as a result, as shown in fig. 4, the finished board reserved for reverse warping is cooled and formed to obtain a flat product, and the problem of board warping is simply, conveniently and quickly solved.

The above embodiments are only used to illustrate the present invention and do not limit the technical solutions described in the present invention; thus, although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted; all such modifications and variations are intended to be included herein within the scope of this disclosure and the present invention and protected by the following claims.

Claims

1. The novel plate warping prevention process is characterized by comprising the following steps: and in the process of cooling and solidifying the base material, reserving shrinkage allowance downwards in advance.

2. The novel board warping prevention process as claimed in claim 1, wherein the method for reserving shrinkage allowance downwards in advance is to make a structure so that the prefabricated board is bent downwards to approximate a spherical surface.

3. The novel board warping prevention process as claimed in claim 2, characterized by comprising the following steps: and placing the plate in the structure with the downward bending direction for cooling and solidification.

4. The novel process of preventing sheet warpage as claimed in claim 3, wherein the downward curvature of the structure during cooling varies with the shape of the sheet as it cools.