SE189934C1

SE189934C1 -

Info

Publication number: SE189934C1
Authority: SE
Publication date: 1964-01-01

Description

Uppfinnare: V W Mantere Prioritet begard frail den 5 mars 1958 (FOrlmndsrepubliken Tuskland) Shdana forfaranden dro redan kanda, vid vilka faner gores sa brandhardigt som mojligt genom att detsamma behandlas i vakuumtryckimpregneringsanordningar med losningar av kanda oorganiska salter. Detta impregneringsforfarande är dock otillrackligt for tjoekare finer, ofta t. o. m. oläuipligt, da de talrika sammanhindande limskikten forhindra losningens intrangande i faneret. Inventor: V W Mantere Priority requested from 5 March 1958 (Federal Republic of Tuscany) These procedures were already known, in which veneers are made as fireproof as possible by treating them in vacuum pressure impregnating devices with solutions of known inorganic salts. However, this impregnation process is insufficient for thicker veneers, often even unsuitable, as the numerous cohesive adhesive layers prevent the penetration of the solution into the veneer.

I enlighet med ett annat kant forfarande impregneras de enskilda tunna fanerskikten fore hoplimningen pa i och for sig kant salt. Far att vid delta fOrfarande uppna_ en fullstandig impregnering av de enskilda fanerskikten, är man tvungen att anvanda hogkoneentrerade saltlosningar. Harigenom uppstar dock den nackdelen, att vid torkningen av faneret en del av saltet respektive salterna utkristalliseras pa fanerets yta. Ph de delar ay fanerytan som tackas ay kristaller kommer limskiktet endast att utbildas svagt eller ofullstandigt. En ytterligare nackdel som vid- detta forfarande bestar i att ett med vattenlOsliga salter impregnerat faner inte ãr fuktbestandigt och att redan fuktig hilt kan astadkomma att de vid fastandet av faneret anvanda spikarna rosta. In accordance with another edge method, the individual thin veneer layers are impregnated before gluing together per se edge salt. In order to achieve a complete impregnation of the individual veneer layers during the delta process, highly concentrated salt solutions must be used. This has the disadvantage, however, that during the drying of the veneer a part of the salt or the salts is crystallized out on the surface of the veneer. If the parts of the veneer surface which are covered with crystals, the adhesive layer will only form weakly or incompletely. A further disadvantage which in this process consists in that a veneer impregnated with water-soluble salts is not moisture-resistant and that already moist hilt can cause the nails used in the fastening of the veneer to rust.

Uppfinningen har till andamal att eliminera dessa nackdelar och den bestar dari, att for impregneringen anvandes en losning, som dels innehaller substanser med aminohartsers reaktionskomponenter, alltsa aminer, sarskilt sadana med mer an en N112-grupp, dels aldehyder, sarskilt formaldehyd eller formaldehyd avspjalkande foreningar, vidare ammonium-salter och slutligen i och for sig kanda impregneringsmedel, varvid de ovannamnda oorganiska salterna valjas sd, att desamma eller en del av dem pa i och for sig Hut salt yerka som katalysatorer vid en efterfoljande varmebehandling, att fanerskikten fore hop- Dupl. kl. 38 h: 2/01 limningen behandlas enskilt med denna impregneringslosning, darefter underkastas en preliminar varmebehandling sa, att darvid atminstone delvis kondenserbara aminohartser uppsth, att darefter de enskilda fanerskikten forses med skikt av Ern pa aminohartsbas och hopfogas och slutligen underkastas en varmebehandling for definitiv kondensation aven av aminohartserna i det inre av faneret. The invention has for its object to eliminate these disadvantages and it consists in that for the impregnation a solution is used which partly contains substances with amino resin reactants, i.e. amines, especially those with more than one N112 group, partly aldehydes, especially formaldehyde or formaldehyde dispersants , further ammonium salts and finally per se known impregnating agents, wherein the above-mentioned inorganic salts are selected so that the same or a part of them per se Hut salt act as catalysts in a subsequent heat treatment, that the veneer layers for hop- Dupl . at 38 h: 2/01 the bonding is treated individually with this impregnation solution, then subjected to a preliminary heat treatment so that at least partially condensable amino resins arise, then the individual veneer layers are provided with layers of Ern on an amino resin base and joined together and finally subjected to a heat treatment for final condensation of the amino resins in the interior of the veneer.

Impregneringen av fanerskikten drives sjalvfallet sa langt, att desamma icke langre aro antandliga. Forfarandet enligt uppfinningen medfor hi. a. den vasentliga fordelen, att en utkristallisering av salter pa fanerets yta forhindras, att vidare ett hallbarare och tjockare limskikt bildas ün yid hittills kanda forfaranden, emedan fanerskikten innelialla samma reaktionskomponenter som de anvanda limsorterna, varigenom mellan limfogen och sjalva fanerskikten ytterligare uppstar en kemisk bindning, att ytterligare de i det inre av faneret utbildade aminohartserna stabilisera traet och forhindra fuktens inverkan pa de yattenlosliga salterna och att slutligen det stora procentuella utskottet vid framstallning av faner enligt de kanda forfarandena vid forfarandet enligt uppfinningen kommer att bli betydligt mindre. The impregnation of the veneer layers is, of course, driven so far that they are no longer flammable. The process according to the invention involves hi. a. the essential advantage that a crystallization of salts on the surface of the veneer is prevented, that furthermore a more durable and thicker adhesive layer is formed in hitherto known processes, since the veneer layers contain the same reactants as the glues used, whereby between the adhesive joint bonding, that further the amino resins formed in the interior of the veneer stabilize the wood and prevent the effect of moisture on the surface-soluble salts and that finally the large percentage increase in the production of veneers according to the known methods of the process according to the invention will be considerably smaller.

Foretradesvis anvandes i impregneringslosningarna aven buffertar, som innehalla en svag syras, exempelvis borsyras, salt med en alkalimetall. Preferably, buffers containing a weak acid, for example boric acid, salt with an alkali metal are also used in the impregnation solutions.

Exempel. En impregneringslosning anvandes, som innehaller 18-20 viktprocent oorganiska salter. Huvuddelen bestar av ammoniumsalter, foretradesvis ammoniumfosfat Dartill kommer annu en buffertsalt, exempelvis natriumborat. Bufferten installes pa ett pH-varde, som ligger mellan 5 och 6,5. FOrhallandet mellan ammonium- och buffertsalt irtgOr ungefar 3:1. Till losningen tillsattes 2— — ung. 10 viktprocent karbarnid och dubbla molmangden formalin. Impregneringen foretages genom doppning vid rumstemperatur eller :fagot forhojd temperatur. Impregneringstiden ãr i allmanhet omkring 24 timmar. Example. An impregnation solution was used, which contained 18-20% by weight of inorganic salts. The main part consists of ammonium salts, preferably ammonium phosphate. In addition there is a buffer salt, for example sodium borate. The buffer is installed at a pH value between 5 and 6.5. The ratio of ammonium to buffer salt is approximately 3: 1. 2— - ung. 10% by weight of carbarnide and double the molar amount of formalin. The impregnation is carried out by dipping at room temperature or: bassoon elevated temperature. The impregnation time is generally around 24 hours.

Sattet och tiden for torkningen aro beroende av forefintliga anordningar. Efter torkningen foretages en varmebehandling for en forkondensering av aminohartserna, ungefar i 20 minuter vid 120-150°C. The set and time for drying depend on existing devices. After drying, a heat treatment is performed for a precondensation of the amino resins, for about 20 minutes at 120-150 ° C.

Hoplimningen av de enskilda fanerskikten genomfores sedan pa normalt salt med hjalp av karbamid- eller melaminhartslim. The gluing of the individual veneer layers is then carried out on normal salt with the aid of urea or melamine resin glue.

Claims

Patent claim:

Procedure for the production of refractory, possibly with a tack layer provided veneer by first impregnation of individual veneer layers with the aid of solutions of per se known fire-promoting inorganic salts, especially ammonium salts with an addition of a buffer salt, for example sodium borate, and subsequent gluing of the various veneer layers, characterized in that amino resins forming reactants are added to the solutions, i.e. amines, especially those with more than one NH2 group, and aldehydes, especially formaldehyde or formaldehyde cleaving compounds, the above-mentioned inorganic salts being sit, that they or some of them act on themselves as catalysts in a subsequent heat treatment, that the veneer layers are impregnated with this impregnation solution to then be subjected to a preliminary heat treatment sit, that at least some condensable amino resins arise, after which d The individual veneer layers are provided with a layer of him on an amino resin base to then be joined and finally subjected to a heat treatment and for definitive condensation of the resulting amino resins also in the hair of the veneer.

Method according to claim 1, characterized in that the surface of the veneer is provided with a protective roof layer of a thermoplastic resin.

Method according to claim 1, characterized in that a paper impregnated with synthetic resin or a laminate layer on canvas is glued to the surface of the veneer. Request publications: Patentskrifter friin Sverige 158 878; United Kingdom 334 408.