CS243667B1 - Method of chemomechanical leakage reduction of formaldehyde and materials bonded by means of formaldehyde resins - Google Patents

Abstract

The solution is to reduce the release of formaldehyde from materials bound by aminoformaldehyde resins; it is used for this purpose ammonia veneer containing 0.5 to 2% amine and amide 3 groups calculated on nitrogen bound to the wood mass of veneer. These groups react chemically and bind to stable the compound slowly and gradually escapes formaldehyde. Veneers approach familiar processes agglomerated materials (particle boards, bonded aminoformaldehyde resins, specifically urea-formaldehyde). This the procedure is particularly applicable in the furniture industry production and construction. Ammonia veneer at the same time it also serves as an ornamental veneer and fills as well as a mechanical barrier against leakage formaldehyde.

Description

(54) A method of chemico-chemical reduction of formaldehyde leakage from formaldehyde resin bonded materials

The invention relates to reducing formaldehyde leakage from aminoformaldehyde resin bonded materials; For this purpose, ammonia veneer is used which contains 0.5 to 2% of the amine and amide 3 groups, calculated on nitrogen, bound to the wood mass of the veneer. These groups react chemically and bind to the stable compound slowly and gradually escaping formaldehyde. Veneers are known in the art to agglomerate materials (particle boards bonded with aminoformaldehyde resins, in particular urea-formaldehyde). This process is particularly useful in furniture manufacturing and construction. Ammonia veneer also serves as a decorative veneer and also serves as a mechanical barrier against formaldehyde leakage.

The present invention relates to a method of chemico-mechanical reduction of free formaldehyde (Fd) leakage from aminoformaldehyde resin bonded materials. In particular, they are agglomerated bulk materials bonded with urea-formaldehyde adhesive (UF).

The starting material to reduce the leakage of Fd is ammonia veneer from wood, pretreated with ammonia to form amine and amide groups capable of reacting with the slow and sustained release of Fd from the UF adhesive into the wood mass, particularly the lignin component, and bind Fd to a stable compound.

To date, too many different methods are known to reduce Fd from UF resin bonded materials. They are based mostly on increasing the proportion of urea in the resin, both in the preparation of the resin itself and immediately before its use in the manufacture of agglomerated materials, or in the case of veneering and sizing.

Another group of processes uses ammonium carbonate to form a stable compound called urotropin when reacted with Fd. For example, sulphite (thickened sulphite leaches produced in the production of cellulose), melamine, phenol, dicyadiamide and many others have been proposed as formaldehyde leakage reducing agents, mainly from particle boards, where the problem is the focus of the problem.

Other procedures use different barrier materials - foils, wallpapers and the like, none of these procedures are entirely satisfactory and therefore new ways are still being sought.

The process of the present PV employs ammonia veneer as a material to chemically capture the released formaldehyde from the bonded particle board (TD) bonded with UF resin, which simultaneously serves both mechanically and as a barrier material.

Ammonia veneers contain amine and amide groups that are capable of scavenging, reacting with formaldehyde to form a stable compound, in addition ammonia veneers serve as ornamental veneers in the manufacture of furniture and other products such as wall, ceiling and the like lining. Thus, ammonia veneer is not only used for the purpose of capturing formaldehyde, but also fulfills the functions of ornamental veneer.

The advantages of the proposed process are that the use of ammonia veneer with a single operation ensures both a substantial reduction in the leakage Fd and the veneer veneer quality with a veneer.

Examples:

I. Ammonia veneer containing amine and amide groups bound in the wood mass in an amount of 0.5 to 1%, calculated on nitrogen, is used for gluing in conventional manner to TD by phenolic glue, such as Rezol F 5243, Rezol F 5245, Fenekol Resol F 101 and the like.

II. Ammonia veneer containing amine and amide groups bound in the wood mass in an amount of 0.8 to 2%, calculated on nitrogen, is used for sizing the TD using a conventional UF adhesive such as Umacol C, Umacol CMR, Dukol M, Diacol and the like.

Claims (1)

SUBJECT OF THE INVENTION Method for reducing the formaldehyde leakage from aminoformaldehyde resin bonded materials, characterized in that ammonia veneers containing amine and amide groups chemically bonded to the wood mass in an amount of 0.5 to 2% calculated on nitrogen are used to creep on the protected material.