SE189268C1

SE189268C1 -

Info

Publication number: SE189268C1
Authority: SE
Publication date: 1963-01-01

Description

Prioritet begard iron den 11 jnli 1959 (osterrike) Som eldskyddsmedel for impregnering eller malning av tra, vavnader eller andra bra.nnbara ainnen anvandas som bekant metallsalter, I. ex. kalcium-, zink- eller ammoniumklorid och ammoniumfosfat i form ax losningar. Aven liar man framstallt eldskyddsmedel genom csemensam pulverisering av enskilda blamlningar av sadana metallsalter till en enhetlig, fast massa, som hi. a. aven innehatter borsyrapulver. Denna blandning anvOndes sedan i en losning av 10-%. Priority begard iron on 11 jnli 1959 (Austria) As a fire protection agent for impregnation or grinding of wood, fabrics or other combustible ainnen is used as known metal salts, I. ex. calcium, zinc or ammonium chloride and ammonium phosphate in the form of solutions. Fire retardants are also prepared by co-pulverizing individual mixtures of such metal salts into a uniform, solid mass, such as hi. a. aven contains boric acid powder. This mixture was then used in a 10% solution.

Forsok aLL anvanda det kanda, eldsakra sekundara eller primara ammoniumfosfatet som impregneringsmedel for trafiberplattor ha icke givit tillfredsstallande resultat, eftersom genom dylika tillsatser plattornas kvalitet avsevart forsamras utan att darigenom i saimna utstrackning flagon eldhammande verkan erhalles. Verkan av detta ammoniumfosfat är soul bekant beroende pa att delta salt vid hogre temperaturer sOnderdelas i ammoniak, vatten och fosforpentoxid, varigenom den frigjorda, icke brannbara ammoniakgasen hammar fOrbranningen. En markbar verkan av delta salt upptrader emellertid forst vid tillsats av c:a 5-10 % av spanvikten. Anvander man emellertid sa stora mangder, kommer ammoniakutvecklingen vid presstemperaturen, vilken uppga till c:a 150°C, att bli sa stor, att plattorna gd solider. Genom den alkaliska reaktionen av ammoniak hindras dessutom hardningen av bindemedlet. Av denna kemikalie kan sdlunda anvdndas endast mangder av app till 2-3 %, men dal.- igenom erhalles icke flagon eldskyddsverkan. Attempts to use the known, fire-resistant secondary or primary ammonium phosphate as an impregnating agent for fibrous plates have not given satisfactory results, since by such additives the quality of the plates is considerably degraded without thereby achieving the same flame retardant effect. The effect of this ammonium phosphate is well known due to the participation of salt at higher temperatures decomposed into ammonia, water and phosphorus pentoxide, whereby the liberated, non-combustible ammonia gas inhibits the combustion. However, a noticeable effect of delta salt only occurs when about 5-10% of the span weight is added. However, if such large amounts are used, the evolution of ammonia at the press temperature, which amounts to about 150 ° C, will be so great that the plates become solid. In addition, the alkaline reaction of ammonia prevents the curing of the binder. Of this chemical, thus, only quantities of app up to 2-3% can be used, but dal.- through which the flake fire protection effect is not obtained.

De ovriga av de namnda salterna, sasom zink- eller kalciumklorid, kunna icke komma till anvandning vid sphnplattor, eftersom de aro hygroskopiska. Ej better ammoniumklorid kan komma till anvandning, eftersomn den genom sin for kraftigt sura reaktion skulle medfOra en alit for snabb hardning av de som bindemedel anvanda urinamnes-, melamin- eller fenolhartserna. Vidare alstras genom dessa foreningar skadliga gaser, eftersom ktorvate och ammoniak friges. The rest of the salts mentioned, such as zinc or calcium chloride, cannot be used in chipboard because they are hygroscopic. No better ammonium chloride can be used, as it would, due to its excessively acidic reaction, lead to an alit for rapid curing of the urinary, melamine or phenolic resins used as binders. Furthermore, through these compounds harmful gases are generated, as ktorvate and ammonia are released.

Medelst talrika forsifok liar det nu kturnat faststallas, att en tillsats av borsyra, i form av granulat eller pulver till traspan efter dessas torkning fore eller efter deras limning ger en icke antandbar spanplatta, nar man i plattan infOr mangder, som uppga till Oretradesvis 3-15 % av traets i tramassan vikt. Verkan av borsyran är att se dart, att denna vid en lemperatur av Over 100°C sOnderfaller i vatten och bortrioxid. Denna bortrioxid smatter vid en ytterligare apphettning redan. vid 294°C. Den smalta bortrioxiden uppsuges av traspanen, varigenom dessa impregneras av den glasliknande bortrioxidsmaltan och icke langre kunna antRndas. En besprutning av traspdnen med small borsyra leder till samma resultat. By means of numerous precursors it has now been established that an addition of boric acid, in the form of granules or powder to the grating after their drying before or after their gluing gives a non-flammable chipboard, when in the plate infor quantities, which amount to Oretradesvis 3- 15% of the traets in the tramass weight. The effect of boric acid is to see dart, which at a temperature of Over 100 ° C decomposes in water and dioxin. This off-oxide slams on a further heating already. at 294 ° C. The narrow boron trioxide is absorbed by the crates, whereby these are impregnated with the glass-like boron trioxide malt and can no longer be ignited. A spraying of the threshing powder with small boric acid leads to the same result.

I och for sig skulle borsyran kunna tillsattas de torkade traspanen aven efter dessas limning. Denna form av borsyratillsats ãr emellertid mycket ogynnsammare, eftersom borsyrapulvret da kommer att anbringas pa limskiktet, varigenom limmets bindekraft icke langre blir fullt verksam. Darigenom att boysyrapulvret kommer att bli belaget mellan de spanytor, som skola limmas samman, erhalles en samre forbindelse mellan de enskilda spanen, vilket emellertid liven det har till foljd en forsamring av spanplattornas mekaniska egenskaper. Salunda uppgar t. ex. vid samma spankvalilet, samma limningsgrad resp. samma halt av fast harts och samma, specifika vikt hos plattorna draghdllfastheten. i tvarriktningen hos desamma vid borsyra- — — tillsats efter sphnens limning till 4,8 kg/cm2 och vid tillsats av borsyra fore limningen till 6,0 kg`cm2. Skulle man emellertid vid en tillsats av borsyra efter spanens limning vilja uppna samma kvalitet has plattorna som vid tillsats av borsyra for plattornas limning, skulle vid den forstnamnda tillsatsen erfordras en avsevart mycket hi5gre tillsats av bindemedel an vid den sistnamnda limningen f8r framstallning av plattorna. Denna Okade bindemedelsatgang skulle emellertid medfOra en fiirdyrning av plattorna. Pa sâ satt impregnerade plattor motsta eld atminstone dubbelt sh lange som normala plattor utan tillsats. Borsyran utvecklar ej heller skadliga gaser, sasom exempelvis klorvate eller ammoniak. Vidare har borsyran en fordelaktig verkan pa spanplattans kvalitet sa till vida, som den minskar vattenabsorptionen och darigenom svallningen av plattorna, vilket uppnits genom en battre hardning av vanliga plastbindemedel, t. ex. urinamne-, melamin- och fenolhartser. Denna bathe hardning beframjas av den svagt sura reaktionen has borsyra (pH-vardet är c:a 5). As such, the boric acid could be added to the dried rags even after gluing them. However, this form of boric acid additive is much more unfavorable, since the boric acid powder will then be applied to the adhesive layer, whereby the bonding force of the adhesive will no longer be fully effective. Because the boy acid powder will be coated between the chip surfaces which are to be glued together, a common connection is obtained between the individual chips, which, however, results in a tightening of the mechanical properties of the chipboards. Salunda states e.g. at the same chip quality, the same degree of gluing resp. the same solid resin content and the same specific gravity of the plates tensile strength. in the transverse direction of the same in the case of boric acid - - - addition after bonding of the sphen to 4.8 kg / cm2 and in the case of addition of boric acid before gluing to 6.0 kg`cm2. However, if an addition of boric acid after gluing the chips were to achieve the same quality as the plates as with the addition of boric acid for the gluing of the plates, the former addition would require a considerably higher addition of binder than the latter gluing to produce the plates. However, this increased binder access would result in an increase in the cost of the plates. In this way, impregnated tiles withstand fire at least twice as long as normal tiles without additives. Boric acid also does not emit harmful gases, such as hydrogen chloride or ammonia. Furthermore, the boric acid has a beneficial effect on the quality of the chipboard to the extent that it reduces the water absorption and thereby the swelling of the plates, which is achieved by a better hardening of ordinary plastic binders, e.g. urea, melamine and phenolic resins. This bath hardening is promoted by the weakly acidic reaction of boric acid (the pH value is about 5).

En pa detta satt hardad platta tandes icke vid behandling med laga, och ej heller glacier den efter avlagsnandet av flamman. Vid kraftigare paverkan av eldsflammor upptrader endast en forkolning. Motstandskraften mot eld är atminstone dubbelt sa star som has en normal, icke impregnerad platta. A hardened plate sitting on this is not toothed during treatment with law, nor does it glaze after the flame has been removed. With a stronger impact of flames, only a charring occurs. The resistance to fire is at least twice that of a normal, non-impregnated plate.

I det foljande skall ges en jamfOrande Over- sikten icke impregnerad platta, en med en c:a 5-procentig 18sning av ammoniumfosfat impregnerad platta och en med en c:a 10-procentig borsyralosning impregnerad spanplatta, vilka samtliga plattor paforts lika mangder av urinamnesplast som bindemedel. Eldprovet utfordes sedan ph sã salt, att alltid lika stora stycken av plattan under sanuna betingelser utsattes fOr paverkan av eld under fern minuter. The following is a comparative overview of non-impregnated plate, a plate impregnated with an approx. 5% solution of ammonium phosphate and a chipboard impregnated with an approx. as a binder. The fire sample is then challenged to such an extent that salt of equal size of the plate is always subjected to the influence of fire for four minutes under the same conditions.

Icke impregnerad platta Plaitan antandes och brinner sedan upp av sig sjalv Platta, impregnerad med c:a 5 % ammoniumfosfat i pulverform Plattan forkolades till halften. Efter avlagsning av flamman brann plattan i ytterligare 30 s och slacknade sedan Platta impregnerad tried °,10 borsyra 1 pulverf arm Plattan forkolades til en tredjedel. Efter flarnmans avlagsnande brann plattan ej vidare och gilidde ej heller Spec. vikt 0,59 0,64 0,64 Vattenabsorption efter 2 h 10,3 % 11,5 % 6,1 % Vattenabsorption efter 24 h 45,4 60,8 % 20,4% Svallning efter 2 h 2,1 % 5,6 % 0,1'7 % Svallning efter 24 h 11,1 % 27,1 % 3,3 % DraghAllfasthet i tvarriktn. 4,8 kg/cm2 1,3 kg/cm2 4,8 kg/crn2 B Oil iallfasthet 198» 142» 223» &Isom framgar av denna oversikt ar den med borsyratillsatsen impregnerade plattan icke endast eldsaker, utan den erhaller en allman kvalitetsforbattring, t. ex. med avseende pa dess vattenabsorption, dess svallning och bajhallfasthet. Non-impregnated plate Plaitan ignited and then burned by itself Plate, impregnated with about 5% ammonium phosphate in powder form The plate was charred to half. After depositing the flame, the plate burned for another 30 seconds and then the plate was impregnated with impregnated wire, boric acid and powder. The plate was charred to one third. After Flarnman's removal, the plate did not burn further and neither did Spec. weight 0.59 0.64 0.64 Water absorption after 2 hours 10.3% 11.5% 6.1% Water absorption after 24 hours 45.4 60.8% 20.4% Swelling after 2 hours 2.1% 5 .6% 0.1'7% Swelling after 24 h 11.1% 27.1% 3.3% Transverse tensile strength. 4.8 kg / cm2 1.3 kg / cm2 4.8 kg / cm2 B Oil strength 198 »142» 223 »& As can be seen from this overview, the plate impregnated with the boric acid additive is not only a fire, but it receives a general quality improvement, t ex. with respect to its water absorption, its swelling and buoyancy.

Claims

Pat entansp rã k:

1. A process for the production of a non-combustible rag board, characterized in that the rag is added to boric acid in the form of granules or powder after their drying and before their gluing. - - -

Process according to Claim 1, characterized in that boric acid was added in an amount of 3%, calculated on the dry mass. Request publications: Patent patent ter frcin Sweden 176 150.