CN1883893A - Method for producing Eo-level wood-slice decorative veneer - Google Patents

Abstract

The invention provides a production method of E ₀ grade veneer decorative veneer, the key of which is to use a formaldehyde-free high-adhesive concealer when applying the concealer on the substrate, and use an E ₀ grade Urea-formaldehyde resin adhesive, and the production site is separated from the production and stacking sites of ordinary veneers, creating a production environment without and with little formaldehyde. The present invention is compatible with the production equipment and process flow system of the existing environment-friendly veneer veneer veneer, and the E ₀ grade veneer veneer produced according to the production method of the present invention is compared with the E ₂ level environment-friendly veneer veneer , the surface bonding strength is higher than 50%, and the formaldehyde emission is as low as 0.3mg/L, which meets the requirements of the E ₀ standard, and further solves the problem of high formaldehyde emission of veneers.

Description

A kind of production method of E0 grade veneer veneer

technical field

The invention relates to a veneer decorative veneer, in particular to a production method of an E ₀ grade veneer veneer with ultra-low formaldehyde emission.

Background technique

The manufacturing process of existing veneer decorative veneer generally is that log is peeled and cut into veneer and promptly becomes plywood through drying, billeting, gluing, cold pressing, hot pressing, sanding. This plywood will serve as a base for the veneer veneer. Then slice the logs of precious tree species with beautiful wood grain and color into veneers, and cut off the raw edges of the veneers with a cutting machine to form veneers of different widths. Then, apply a concealer on the substrate, and after drying, use a glue applicator to apply an adhesive on the substrate, and then manually stick the veneer on the substrate in order to form a veneer blank, which is sent to a cold press for cold pressing. In order to speed up the initial bonding of the veneer and the substrate, generally after 1-2 hours, it can be sent out for cold sanding to deal with the artificial overlapping seams in the veneer veneer, and then manual inspection is required to further repair the veneer and For the seam defects that appear in the sanding process, the base plate is then sent to the hot-pressing process, and the base plate is dried under pressure with a hot press, so that the glue is thermally cured and reaches the standard bonding strength. At this time, the base plate becomes The decorative veneer is finished. Since the traditional urea-formaldehyde resin adhesive is used in production, the decorative veneer produced by the above method has a higher formaldehyde emission.

With the development of social economy, countries all over the world are paying more and more attention to environmental quality, and my country is no exception. In view of the serious impact of formaldehyde on the environment and human health, the country has made strict regulations on the amount of formaldehyde released in wood-based panel products. On January 1, 2002, the GB18580-2001 mandatory standard "Limits of formaldehyde release in wood-based panels and their products for interior decoration materials" was promulgated. Since July 1, 2002, the market has stopped selling products that do not meet the national standards. The limit of formaldehyde is divided into two standards, namely E ₁ and E ₂ , the requirement for _E1 level is ≤1.5mg/L; the requirement for E2 level is ≤5.0mg/L. The promulgation and enforcement of this standard will gradually withdraw products with high formaldehyde release from the market. But even the release of formaldehyde in E ₁ and E ₂ wood-based panel products that meet the standards will have a certain impact on human health. Therefore, developed countries such as Japan and Europe have proposed and implemented a higher standard E ₀ level (ie ≤0.5mg/L). However, this level of wood-based panels has a high technical content and is difficult to manufacture, so there are no products available in China at present.

Contents of the invention

The purpose of the present invention is to provide a kind of E ₀ grade veneer veneer veneer and production method thereof with ultra-low formaldehyde emission (ie≤0.5mg/L).

The present invention is achieved in the following way: a formaldehyde-free high-adhesive concealer is used when smearing the concealer on the substrate, and an E ₀ grade urea-formaldehyde resin adhesive is used when gluing, and the production site is the same as the production of ordinary veneers. , Isolate the stacking place, and create an aldehyde-free and low-aldehyde production environment. The present invention is compatible with the production equipment and process flow system of the existing environment-friendly veneer veneer veneer, and the E ₀ grade veneer veneer produced according to the production method of the present invention is compared with the E ₂ level environment-friendly veneer veneer , the surface bonding strength is higher than 50%, and the formaldehyde emission is as low as 0.3mg/L, which meets the requirements of the E ₀ standard, and further solves the problem of high formaldehyde emission of veneers. E ₀ -grade thin wood decorative veneer is a green and environmentally friendly building decoration material. Its promotion and application is of great significance to reduce the harm of formaldehyde to people's health, build green and healthy homes, create a healthy living environment, and improve people's quality of life. It is The replacement product of the common thin wood decorative veneer widely produced and used in the market at present has a bright market prospect.

Description of drawings

Fig. 1, is the production procedure flowchart of the present invention.

Detailed ways

Combined with Figure 1, in the case of isolation from the production and storage places of ordinary veneers, the logs are cut into veneers, dried and formed, and then coated with E ₀ grade urea-formaldehyde resin adhesive. This kind of adhesive is an ultra-low formaldehyde-emitting adhesive composed of urea-formaldehyde resin as the main component and various modifiers such as melamine, thiourea and ethylene urea. Then carry out cold pressing, hot pressing and sanding to become plywood. This plywood will serve as a base for the veneer veneer. At the same time, the logs of precious tree species with beautiful wood grain and color are sliced into veneers after hydrothermal treatment, and the raw edges of the veneers are cut off with a cutting machine to form veneers of different widths. Then, apply a formaldehyde-free high-adhesive concealer on the plywood substrate to cover up the color difference on the substrate surface. Since the thickness of the veneer used for the veneer is 0.1-0.2mm (referring to the veneer attached to the surface of the conventional three-layer plywood), if the ordinary aldehyde-containing concealer is used, the formaldehyde contained in it will be released easily. Therefore, the concealer should be formaldehyde-free. of. The main components of this formaldehyde-free concealer are: 20-35% of latex white glue, 2-10% of titanium dioxide, 15-25% of lithopone, 10-15% of calcium carbonate, 0.5-2% of pigment and appropriate amount water composition. After the concealer is dry, use a glue applicator to coat the E ₀ grade urea-formaldehyde resin adhesive on the substrate, and the dosage is about 65-75g/m ² . Then, the veneer is neatly pasted on the substrate in turn by hand to form a veneer blank, which is sent to a cold press for cold pressing to speed up the initial bonding of the veneer to the substrate. Generally, after 1-2 hours, it can be sent out for cold processing. Sand, in order to deal with the artificial seam produced in the thin wood veneer, after that, manual inspection is required to further repair the seam defects that appear in the veneer and sanding, and then send the blank board to the hot pressing process, and use hot pressing The machine pressurizes and dries the slab to heat-cure the glue and reach the standard bonding strength. At this time, the slab becomes the finished product of E ₀ grade veneer veneer.

Claims (3)

1. A production method of E ₀ grade thin wood decorative veneer is that logs are rotary cut into veneers and become plywood substrates through drying, billet formation, gluing, cold pressing, hot pressing and sanding, and then, on the substrates Apply concealer, dry and then apply glue on the substrate, and then neatly paste the veneer on the substrate in order to form a veneer blank, send it to the cold press for cold pressing, and then send it out for cold sanding, hot pressing to make the glue hot Curing, characterized in that: a formaldehyde-free high-adhesive concealer is used when smearing the concealer on the substrate, and an E ₀ -grade urea-formaldehyde resin adhesive is used when the glue is applied, and the production site is the same as the production of ordinary veneers, The stacking site is isolated to create an aldehyde-free and low-aldehyde production environment. 2. according to claim 1. the production method of a kind of E ₀ grade veneer veneer veneer described in claim 1, it is characterized in that said a kind of formaldehyde-free type high-adhesive concealer is made of latex 20-35%, titanium White powder 2-10%, lithopone 15-25%, calcium carbonate 10-15%, pigment 0.5-2% and appropriate amount of water. 3. according to claim 1. the production method of a kind of E ₀ grade veneer decorative veneer described in claim 1, it is characterized in that said E ₀ grade urea-formaldehyde resin adhesive is to be main component with urea-formaldehyde resin, add melamine, thiourea, Ultra-low formaldehyde emission adhesive composed of multiple modifiers of ethylene urea.