DK160412B - Method for reducing the emission of formaldehyde from chipboards and fibreboards veneered with a superior quality layer - Google Patents
Method for reducing the emission of formaldehyde from chipboards and fibreboards veneered with a superior quality layer Download PDFInfo
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- DK160412B DK160412B DK255385A DK255385A DK160412B DK 160412 B DK160412 B DK 160412B DK 255385 A DK255385 A DK 255385A DK 255385 A DK255385 A DK 255385A DK 160412 B DK160412 B DK 160412B
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Opfindelsen angår en fremgangsmåde til formindskelse af formaldehydafgivelsen fra spån- og fiberplader, der er finerede med et lag af ædlere kvalitet, i det følgende kaldet kvalitetslag, hvor spån- eller fiberpladerne hører til emissions-5 klassen El, og hvor finerlaget er anbragt ved anvendelse af urinstofformaldehydharpiks med højt formaldehydindhold.The invention relates to a method for reducing the formaldehyde release from particle board and fiber veneer, which are veneered with a layer of higher quality, hereinafter referred to as a quality layer, where the particle board or fibreboard belongs to the emission class E1 and where the veneer layer is applied during use. of high formaldehyde urea resin.
Ved træspånplader forstås plader af træspåner, der varmpresses med et bindemiddel af et klæbestof af syntetisk harpiks. Ved 10 hjælp af spånernes størrelse, form og arrangement og mængden af andelen af syntetisk harpiks, der sædvan 1igvis ligger i intervallet fra 5 til 10%, kan træspånpladernes egenskaber varieres kraftigt. Træspånpladerne kan belægges med dekorationsfilm, grunderingsfilm og finér, f.eks. med værdifulde træsor-15 ter.Wood chipboard is meant wood chipboard which is hot pressed with a binder of a synthetic resin adhesive. By virtue of the size, shape and arrangement of the chips, the amount of synthetic resin, which is usually in the range of 5 to 10%, can greatly vary the properties of the wood chips. The wood chipboard can be coated with decorative film, primer film and veneer, e.g. with valuable wood varieties.
I Forbundsrepublikken Tyskland er forbruget af træspånplader steget kraftigt i de senere år. Mens produktionen af træspånplader i 1969 lå på 3,4 millioner kubikmeter, steg den i 1971 20 til 4,3 millioner kubikmeter og androg i 1980 allerede 6,2 millioner kubikmeter.In the Federal Republic of Germany, the consumption of wood chipboard has increased sharply in recent years. While the production of wood chipboard in 1969 was 3.4 million cubic meters, in 1971 it rose 20 to 4.3 million cubic meters and in 1980 already reached 6.2 million cubic meters.
Urinstofharpikser eller aminoplastarter er langt de mest benyttede spånpladebindemidler. De udmærker sig ved en gunstig 25 pris og en høj styrke af limningen og muliggør desuden korte presset ider. Urinstofharpikserne har imidlertid den store ulempe, at de under brug af spånpladerne afgiver formaldehyd, der ikke blot har en ubehagelig lugt, men også giver sundhedsrisiko. Derfor er anvendelsen af uri nstofharpikser som binde-30 middel underlagt bestemte begrænsninger.Urea resins or aminoplast species are by far the most commonly used chipboard binders. They are distinguished by a favorable price and high strength of the glue and also enable short pressed ideas. However, the urea resins have the great disadvantage that, when using the particle board, they release formaldehyde which not only has an unpleasant odor but also presents a health risk. Therefore, the use of urea resins as a binder is subject to certain limitations.
Det er allerede i dag muligt også at fremstille aminoplast-bundne træspånplader med en formaldehydafgivelse - målt efter perforatorfremgangsmåden (DIN EN 120, "Bestimmung von Formal-35 dehyd in Spanplatten, Perforatormethode", Beuth-Verlag, Berlin, Koln) - på under 10 mg/100 g absolut tør plade. Byggespånplader i denne emissionsklasse (El) må anvendes udækkedeIt is already possible today to also make aminoplast-bonded wood chipboard with a formaldehyde release - measured according to the perforator method (DIN EN 120, "Bestimmung von Formal-35 dehyd in Spanplatten, Perforator Method", Beuth-Verlag, Berlin, Koln) - in less than 10 mg / 100 g absolute dry plate. Construction chipboard in this emission class (E1) may be used uncovered
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2 og ubelagte og ubegrænset i beboelsesrum (jvf. ETB-Richtlinie 1980: "Richt-l inie iiber die Verwendung vor Spanplatten hin-sichtlich der Vermeidung unzumutbarer Formaldehydkonzentration in der Raumluft", April 1980 udgave, Beuth-Verlag, Berlin, 5 Koln).2 and uncoated and unrestricted in living space (cf. ETB Directive 1980: "Directly in use using the Spanplaten in view of avoidable formaldehyde concentration in the room air", April 1980 edition, Beuth-Verlag, Berlin, 5 columns) .
Isocyanater er hidtil kun blevet anvendt i ringe omfang som bindemiddel for spånplader. Specielt diphenylmethandiisocyanat har imidlertid vist sig som et fremragende bindemiddel, med 10 hvilke der kan fremstilles plader med lang holdbarhed. Prisen på disse produkter har imidlertid hidtil forhindret en bredere anvendelse.Isocyanates have so far only been used to a small extent as binder for particle board. However, diphenylmethane diisocyanate in particular has proved to be an excellent binder with which long-lasting sheets can be produced. However, the prices of these products have so far prevented wider use.
I den offentliggjorte europæiske patentansøgning nr. 0 012 169 15 beskrives spån- eller fiberplader, som består af flere lag og fortrinsvis er aminoplastbundne, hvilke plader i et indre område, fortrinsvis i mellemlaget, som bindemiddel har et klæbestof, som ikke hører til gruppen af aminoplastarter, f.eks. di isocyanat, og som er karakteriserede ved, at der til dette 20 indre område kun anvendes bindemidler, hvis hærdning ikke påvirkes i negativ retning af tilstedeværelsen af yderligere formaldehydreaktive stoffer, hvorved bindemidlet blandes med disse yderligere stoffer i form af ammoniak, ammoniumcarbonat, urinstofarter, thiourinstofarter, melamin eller dicyandiamid, 25 der direkte, eventuelt også indirekte ved hjælp af spaltningsprodukter, reagerer på afbindende måde med det efter presningen af pladen stadigt tilbageværende eller fritblivende formaldehyd under fugtigheds- og/eller varmepåvirkning. 1 2 3 4 5 6Published European Patent Application No. 0 012 169 15 discloses particle or fiber sheets consisting of several layers and preferably aminoplastic bonded, which sheets in an inner region, preferably in the intermediate layer, which binder has an adhesive which does not belong to the group of aminoplast species, e.g. di isocyanate, and characterized in that for this inner region only binders are used whose curing is not adversely affected by the presence of additional formaldehyde reactants, thereby mixing the binder with these additional substances in the form of ammonia, ammonium carbonate, urea species, thiourea species, melamine or dicyandiamide, which directly, optionally also indirectly by means of cleavage products, react in a binding manner with the residual or free-standing formaldehyde remaining under moisture and / or heat after pressing the plate. 1 2 3 4 5 6
Den offentliggjorte europæiske patentansøgning nr. 0 006 486 2 angår en fremgangsmåde til formindskelse af formaldehydafgi 3 velsen fra aminoplastbundne spån- eller fiberplader, ved hvil 4 ken fremgangsmåde der på pladernes overflade i varm tilstand 5 og kort efter deres udtagelse fra varmpressen anbringes urin- 6 stofarter eller andre ammoniakfraspal tende stoffer i form af en vandig opløsning.Published European Patent Application No. 0 006 486 2 relates to a method for reducing formaldehyde release from aminoplastic bonded chipboard or fibreboard, in which method 4 is applied to the surface of the plates in hot state 5 and shortly after their removal from the hot press. substances or other ammonia-depleting substances in the form of an aqueous solution.
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Disse El-plader fineres imidlertid i krydsf i nerindustrien i mange tilfælde med kvalitetslag, f.eks. med mahogni, f.eks. til fremstilling af paneler. I krydsfinerindustrien er det til finering sædvanligt at anvende urinstof-formaldehydharpikser 5 med højt formaldehydindhold (molforhold urinstof: formaldehyd 1:1,6 til 1:1,8) som bindemiddel mellem fineringen og pladen.However, in many cases these quality panels are veneered in plywood with quality layers, e.g. with mahogany, e.g. for the manufacture of panels. In the plywood industry, it is customary to use high formaldehyde urea-formaldehyde resins 5 (molar ratio of urea: formaldehyde 1: 1.6 to 1: 1.8) as a binder between the veneer and the plate.
Også ved anbringelse af plastoverflader til møbelbygning anvendes varmhærdende, formaldehydrige urinstof-formaldehydhar-10 pikser.Also, when applying plastic surfaces to furniture building, thermosetting, formaldehyde-rich urea-formaldehyde resins are used.
Ved anvendelsen af disse bindemidler kan formaldehydafgivelsen fra de finerede eller på anden måde belagte plader alt efter belægningstype, træsort, tykkelse, skæreretning og fremstil-15 1ingsbetingelser forhøjes så meget, at de lovmæssige krav ikke længere kan opfyldes. Også afspærringens formaldehydformindskende virkning (f.eks. ved hjælp af fineringen) går tabt og bliver fuldstændig overgået (jvf. Marutzky, R., Mehlhorn, L. og Wenzel, W. , 1981: "Empfehlungen zur Verwendung vor Span-20 platten im Mobelbau", foredrag holdt i anledning af Mobil Oil AG1 s symposium i Grainau den 18. september 1981). Dette gælder især, når de finerede plader eller panelers formater er meget små (jvf. ETB-retningslinier).By using these binders, the release of formaldehyde from the veneered or otherwise coated sheets, depending on the type of coating, wood type, thickness, cutting direction and manufacturing conditions, can be increased so much that the legal requirements can no longer be met. Also, the formaldehyde-reducing effect of the barrier (for example, by means of the veneer) is lost and completely surpassed (cf. Marutzky, R., Mehlhorn, L. and Wenzel, W., 1981: "Empfehlungen zur Verwendung vor Span-20 platten im Mobelbau ", lecture given at Mobil Oil AG1's symposium in Grainau on September 18, 1981). This is especially true when the size of the veneered sheets or panels is very small (cf. ETB guidelines).
25 Formålet med den foreliggende opfindelse er således at tilvejebringe en fremgangsmåde, ved hjælp af hvilken det er muligt at formindske formaldehydafgivelsen fra spån- og fiberplader, hvorpå er anbragt kvalitetslag, hvor pladerne selv tilhører emissionsklassen El, og hvor kvalitetslagene især er værdiful-30 de finertræarter og er blevet anbragt ved anvendelse af urinstof-formaldehydharpikser med højt formaldehydindhold.Thus, the object of the present invention is to provide a method by which it is possible to reduce the release of formaldehyde from particle board and fiber sheets, to which are placed quality layers, where the sheets themselves belong to the emission class E1 and where the quality layers are especially valuable. veneer wood species and have been applied using high formaldehyde urea-formaldehyde resins.
Den i den ovennævnte europæiske patentansøgning nr. 0 006 486 beskrevne fremgangsmåde egner sig ikke til dette formål, da 35 kvalitetslagene ved påsprøjtning af urinstof eller andre ammo-niakfraspaltende stoffer i form af en vandig opløsning på de allerede finerede plader ville blive beskadiget eller stærkt misfarvet.The process described in the aforementioned European Patent Application No. 0 006 486 is not suitable for this purpose, as the quality layers by spraying urea or other ammonia-splitting substances in the form of an aqueous solution on the already veneered plates would be damaged or severely discolored. .
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Det har nu overraskende vist sig, at det ovennævnte formål kan opfyldes ved, at pladerne før fineringen behandles på i og for sig kendt måde med vandige opløsninger af urinstof og/eller andre ammoniakfraspal tende forbindelser, og at kvalitetslagene 5 efterfølgende anbringes på i og for sig kendt måde.It has now surprisingly been found that the aforementioned purpose can be achieved by treating the plates before the veneer in a manner known per se with aqueous solutions of urea and / or other ammonia-dispersing compounds, and that the quality layers 5 are subsequently applied to and for say well known way.
De ifølge opfindelsen behandlede plader fineres fortrinsvis med mahognitræ.The sheets treated according to the invention are preferably veneered with mahogany wood.
10 Ved fremgangsmåden ifølgfe opfindelsen anvendes som formaldehydreaktive stoffer urinstof og/eller andre ammoniakfraspal-tende forbindelser, som f.eks. ammoniumcarbonat. Disse stoffer er beskrevet i den europæiske patentansøgning nr. o 012 169. Ved fremgangsmåden ifølge opfindelsen skal formaldehyd-15 afgivelsen fra selve råpladerne ikke formindskes, da der ved fremgangsmåden ifølge opfindelsen anvendes plader i emissionsklasse El, til hvis anvendelse der ikke af byggemyndighederne kræves yderligere reduktion af formaldehydemissionen derfra. Det er muligt ifølge opfindelsen at finere plader, der næsten 20 ikke afgiver formaldehyd, under anvendelse af urinstof-form-aldehydharpikser, uden at den færdige, finerede plade afgiver utilladelige mængder formaldehyd. Spånpladen fungerer som bærer for formaldehydopfangeren. Ved hjælp af den rumligt adskillelse af urinstof-formaldehydharpiksen og formaldehydop-25 fangeren går hærdningen af harpiksen uforstyrret og nemt fra hånden, mens det frie formaldehyd opfanges i pladen.In the process of the invention, urea and / or other ammonia-depleting compounds such as, e.g. ammonium carbonate. These substances are described in European Patent Application No. 0 012 169. In the process according to the invention, the release of formaldehyde from the raw plates themselves is not to be reduced, since in the process according to the invention, plates of emission class E1 are used for which use is not required by the building authorities further. reduction of the formaldehyde emission therefrom. It is possible according to the invention to use veneered plates which do not release formaldehyde almost 20 using urea-shaped aldehyde resins without the final veneered plate delivering inadmissible amounts of formaldehyde. The particleboard acts as a carrier for the formaldehyde scavenger. By means of the spatial separation of the urea-formaldehyde resin and the formaldehyde collector, the curing of the resin goes undisturbed and easily from the hand while the free formaldehyde is captured in the plate.
Under fineringsforløbet vandrer det i fri form foreliggende formaldehyd fra overfladen af pladerne til pladernes indre, 30 hvor formaldehydopfangerne befinder sig. Der reagerer det ind-diffunderende formaldehyd med formaldehydopfangerne. På denne måde kan formaldehydafgivelsen fra de finerede plader formindskes drastisk. 1During the finishing process, the free-form formaldehyde migrates from the surface of the plates to the interior of the plates, where the formaldehyde collectors are located. There, the diffusing formaldehyde reacts with the formaldehyde scavengers. In this way, the formaldehyde release from the veneered plates can be drastically reduced. 1
Ved fremgangsmåden ifølge opfindelsen anvendes vandige opløsninger af urinstof og/eller andre ammoniakfraspal tende forbindelser. De vandige opløsninger kan have koncentrationer i in-In the process of the invention, aqueous solutions of urea and / or other ammonia dispersing compounds are used. The aqueous solutions may have concentrations in
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5 tervallet fra 5 til 60 vægt%, fortrinsvis fra 30 til 50%. De fremstilles på enkel måde ved, at man opløser de pågældende forbindelser i vand. Som ammoniakfraspaltende forbindelser kan der anvendes ammoniumcarbonat og ammoniumbicarbonat. Der an-5 vendes fortrinsvis urinstof i blanding med ammoniumcarbonat.5 ranges from 5 to 60% by weight, preferably from 30 to 50%. They are prepared simply by dissolving the compounds in water. As ammonia decomposing compounds, ammonium carbonate and ammonium bicarbonate can be used. Preferably, urea is used in admixture with ammonium carbonate.
Anvendelsesområdet for den foreliggende opfindelse er ikke begrænset til aminoplastharpiksbundne spånplader i emissionsklasse El, men fremgangsmåden ifølge opfindelsen kan med suc-10 ces anvendes på isocyanatbundne spånplader og phenolformalde-hydharpiksbundne spånplader, der i sig selv ikke afgiver noget eller næsten intet formaldehyd, men som ved finering med ami-noplastharpikser som bindemiddel får et formaldehydafgivelses-potential. Også emissionsfattige fiberplader kan behandles ved 15 fremgangsmåden.The scope of the present invention is not limited to aminoplast resin bonded particle board of emission class E1, but the process of the invention can be successfully applied to isocyanate bonded chipboard and phenol formaldehyde resin bonded particle boards which in themselves do not release any or almost no formaldehyde veneering with aminoplast resins as a binder has a formaldehyde release potential. Emission-poor fiber boards can also be treated by the method.
Det følgende eksempel belyser opfindelsen.The following example illustrates the invention.
Eksempi 20Example 20
En spånplade i emissionsklassen El (perforatorværdi på henholdsvis 8,0 mg (jodometrisk) og 6,1 mg (fotometrisk)/100 g absolut tør plade) blev bestrøget med 220 g/m2 af en 50% urinstof /formaldehyd-harpiksopløsning (molforhold 1:1,6) og derpå 25 belagt med finer (mahogni, tykkelse 0,6 mm).A particle board of emission class E1 (perforator value of 8.0 mg (iodometric) and 6.1 mg (photometric) / 100 g absolute dry plate, respectively) was coated with 220 g / m2 of a 50% urea / formaldehyde resin solution (molar ratio 1 : 1.6) and then 25 coated with veneer (mahogany, thickness 0.6 mm).
Til sammenligning blev den samme plade før fineringen besprøjtet under de samme betingelser med en 30% urinstofopløsning i en mængde på 100 g/m2 og derpå fineret som beskrevet.In comparison, the same plate before spraying was sprayed under the same conditions with a 30% urea solution in an amount of 100 g / m2 and then veneered as described.
30 I den følgende tabel er gengivet omfanget af formaldehydafgivelsen fra de finerede spånplader efter WKl-metoden (Roffael, E., 1975: "Messung der Formaldehydabgabe. Praxisnahe Methode zur Ermittlung der Formaldehydabgabe harnstoffharzgebundener 35 Spanplatten flir das Bauwesen". Holz-Zentralblatt 101, side 1403 til 1404). Omfanget af formaldehydafgivelsen fra ufinere-de plader er ligeledes taget med i visse tilfælde. Af angivel- 630 The following table shows the extent of the formaldehyde release from the veneered particleboard according to the WK1 method (Roffael, E., 1975: "Messung der Formaldehydegababe. Praxisnahe Methode zur Ermittlung der Formaldehydegab harnstoffharzgebundener 35 Spanplatten flir das Bauwesen". 101 Holz-Zentral pages 1403 to 1404). The extent of formaldehyde release from unfinished sheets is also included in some cases. Of statement- 6
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serne i tabellen ses tydeligt, at der ved behandlingen af spånpladerne med formaldehydreaktive stoffer sker en betragtelig formindskelse af formaldehydafgivelsen i forhold til de ubehandlede plader. Denne formindskelse ligger efter en prøve-5 tid på 144 timer i WKI-testen på over 30%. Omfanget af formaldehydafgivelsen blev, hvad angår de finerede spånplader, ikke bestemt efter perforatormetoden, eftersom perforatormeto-den ifølge ETB-retningsli ni erne ikke er anvendelig til belagte eller på anden måde overfladebehandlede plader.The table in the table clearly shows that the treatment of the particle boards with formaldehyde reactants significantly reduces the release of formaldehyde compared to the untreated plates. This decrease is after a trial time of 144 hours in the WKI test of over 30%. The extent of formaldehyde release for the veneered particle board was not determined by the perforator method since the perforator method according to the ETB guidelines is not applicable to coated or otherwise surface treated panels.
10 15 20 25 1 3510 15 20 25 1 35
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Claims (5)
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DK255385A DK160412C (en) | 1985-06-06 | 1985-06-06 | PROCEDURES FOR REDUCING THE PRESENT HYDRAULIC RELEASE FROM CHIP AND FIBER PLATES FINISHED WITH A LAYER OF EARLY QUALITY |
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| DK255385 | 1985-06-06 | ||
| DK255385A DK160412C (en) | 1985-06-06 | 1985-06-06 | PROCEDURES FOR REDUCING THE PRESENT HYDRAULIC RELEASE FROM CHIP AND FIBER PLATES FINISHED WITH A LAYER OF EARLY QUALITY |
Publications (4)
| Publication Number | Publication Date |
|---|---|
| DK255385D0 DK255385D0 (en) | 1985-06-06 |
| DK255385A DK255385A (en) | 1986-12-07 |
| DK160412B true DK160412B (en) | 1991-03-11 |
| DK160412C DK160412C (en) | 1991-08-19 |
Family
ID=8113164
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| DK255385A DK160412C (en) | 1985-06-06 | 1985-06-06 | PROCEDURES FOR REDUCING THE PRESENT HYDRAULIC RELEASE FROM CHIP AND FIBER PLATES FINISHED WITH A LAYER OF EARLY QUALITY |
Country Status (1)
| Country | Link |
|---|---|
| DK (1) | DK160412C (en) |
-
1985
- 1985-06-06 DK DK255385A patent/DK160412C/en not_active IP Right Cessation
Also Published As
| Publication number | Publication date |
|---|---|
| DK255385A (en) | 1986-12-07 |
| DK255385D0 (en) | 1985-06-06 |
| DK160412C (en) | 1991-08-19 |
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Legal Events
| Date | Code | Title | Description |
|---|---|---|---|
| PBP | Patent lapsed |