DE231148C - - Google Patents

Description

IMPERIAL

PATENT OFFICE,

The invention relates to a method for Impairment of porous materials such as wood, Sawdust, wood pulp, cork, cotton, asbestos, (■ fiber wool, etc., and consists in that one this Slplfc only a mixture of form- ' aklchyd and phenols and causes the condensation of both components in the substances to be impregnated. According to a particular embodiment of the method

to subject the mixture of formaldehyde and. Phenols initially a partial condensation, whereupon one introduces liquid mass into the substances to be impregnated and finally the condensation ends in these.

Compared to / de.1'1 known impregnation processes, at which z. B. Resins or the like / body used for impregnation .be, the main difference is that with the known methods the impregnation material (e.g. resin) the impregnation chemically and physically

remains unchanged while. at the previous.

. A new process through synthesis.

Body is 'formed' in the pores of the 'substance to be impregnated' Achieved the advantage that not only the impregnated fabrics get essential new properties, as detailed below: .wer-, den, but that Zwjschenkonden -.- sation'ssliifett can be obtained that for certain. Cases made beneficial can be /

A method has become known in which a mixture of creosote oil and resin is used as the impregnation liquid 40

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while formaldehyde is used comes to the foul-preventing Properties of the impregnation liquid still to increase; the impregnation takes place at elevated temperature and under pressure.

The known process differs from the present process in that creosote oil is used together with resin. The resin is the main product that causes the hardening. The wood impregnated by this known method, when it is reheated, allows the impregnation material to overflow because it melts again. The wood treated according to the present method retains the impregnation material in spite of the repeated heating, because the substance produced in the fibers is insoluble and infusible . ';'/.'.""'..'.:.'■ ·

The insolubility and insolubility of the Condensation product is brought about fastest by the fact that the impregnated Body is subjected to heat and pressure at the same time.

If, for example, wood is to be "impregnated" according to the present method, then a mixture of / approximately equal parts commercial heliol and 40 percent is required. Ilntulels-.form'aldehyde solution prepared and the wood immersed in this' solution until / it has absorbed enough liquid / ^{; ί}

■ .This 'impregnation' can be achieved through the use of known aids. ^z ^ vacuum or pressure that has been established. In the event of using sawdust, small items

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Cork, bulk or fibers; the material can simply be mixed with the liquid too a homogeneous mass can be processed. In any case, the impregnated materia) then gradually up to about 120 to 150 ° C, several hours. Under these conditions the synthesis takes place, and the desired hard, insoluble, infusible Condensation product is formed inside the mass, with a corresponding The amount of water released by the following Drying can be driven off. It is known that the synthesis is carried out by. Application - of suitable amounts of so-called condensers or catalytic agents, e.g. B. by small amounts of inorganic or organic acids, salts, or better by adding basic ones Links.

Whatever condensing agent may be used, they simply can be mixed with the reaction liquids or separately during or before loading. action can be added. A block of wood e.g. B. can first with a solution of zinc chloride and then impregnated with the mixture of phenol-formaldehyde or vice versa; in either case, the contact with the zinc salt becomes the reaction between phenol and formaldehyde, which, afterwards through. Heating can be completed. This Procedure is its' economical and expedient: for the treatment of railway sleepers. Instead of using a mere mixture of phenols and aqueous formaldehyde, A mixture obtained by dissolving polymerized formaldehyde can also be used in · phenols. But it's cheaper and easier to mix ordinary phenol and formaldehyde solution so much solid. Add sodium chloride,. · That the water is removed from the mixture and a separation into two liquid layers occurs, whose; heavier mainly from saturated aqueous saline solution, and its easy--. ' tere mainly from a drained lo- ' simg out. Formaldehyde in phenol. The. amount of salt to apply is not so long of importance as a slight excess of 50% salt remains undissolved. Stir or shake.

] promotes the effect, and you can

j ■ · -. both liquids after some time, have stood, easily separate from each other.

The inventor has found that calcium chloride can also be used instead of sodium chloride, any salt in general ί Solubility sufficient to make the mixture water

{to withdraw; However, sodium chloride or calcium chloride are popular because of their wobble preferable. The dehydrated solution consisting of formaldehyde and phenol can be used for the present purpose either alone or in conjunction with suitable condensing Agents are used.

Whether the water-containing or · 'dehydrated mixture is applied, in any case, it is advantageous to use the synthesis in a suitable particular To initiate vessels rather than the whole synthetic process in or around the Fibers or cells'. It is open this way possible to bring the mixture to a point in which, although the reaction has started, the product is highly fluid or soluble, and then the porous .material to impregnate or to mix this with that mixture and then the reaction zii finish by heating until the insoluble state has occurred. It is known, that if one is in a vessel which is provided with a reflux condenser, a Mixture of roughly the same. Parts of commercial phenols or formaldehyde alone odci heated or boiled in the presence of condensing agents, liquid or viscous The mass is deposited under an aqueous layer floating above it; the moving part can then be interrupted and the. aqueous layer removed, or the water by evaporation be driven out. If heating doesn't continue for too long, go then the deposited product will still be liquid enough to allow light impregnation to allow ;. but if it has become too viscous, then it can be used for this purpose be diluted with suitable solvents'. The liquid or viscous produced in this way has liquid initial condensation product. the great advantage over the pure mixture Phenol and formaldehyde predict that its use will shorten the time during which ioo the impregnated mass must be subjected to heat in order to "harden it"; in addition, little or no water is released during the hardening process in comparison to the amount of water released when crude mixtures of phenol and formaldehyde are used will. This does not save me the subsequent drying, but a great advantage achieved in cases in which the presence of large amounts of free Water is harmful, such. B. in the manufacture of electrical equipment in which the insulating properties of the product are to be harnessed. ·

In what way also the liquid odci ■ viscous initial condensation product produced has been, the process of impregnation and hardening remains essentially the same as in the case described first. iao

Under the name »Phenol« ötler »Phenole« not just the actual phenol

Claims (4)

understood, but also the homologues. Mixtures of such phenols can also be used. . Colors or coloring agents can also be added to the reactants to change the color or appearance of the manufactured items. as well Products that change the smell can also be added. The procedure is for ίο many purposes ·· applicable, e.g. for impregnation and preservation of wood, for the production of artificial wood, cork mixtures, Insulation materials, etc. If loose, fibrous, or cellular materials - such as wood pulp, cotton, sawdust, Cork, glass wool or asbestos - should be hardened, so it may or may not be necessary it may be desirable to: subject the impregnated mass to pressure during hardening, to ensure a better connection between the parts or the finished item to give a desired shape; ' herezdjkönncn special forms are used, or the fibrous or cellular material can first brought into suitable forms, such as ' ■■ /,. B. cardboard or pressed wood pulp stands, and the substantially latter can utiSj Däi 1 / f ^ dei impregnation and curing subjected to ^'1 ^ VCR. ·, · as ( "hen the described. In the manufacture of objects. soluble, infusible Kondensätionsprodukt'- Containing phenols and formaldehyde, it is advantageous to carry out the hardening with simultaneous pressure action in order to ensure homogeneity and to avoid the formation of a porous or spongy mass during the escape of volatile products that if the product is made inside a fibrous or cellular material, one can heat at significantly higher temperatures without fear of the disadvantages mentioned and without having to use artificially increased pressure. which would be obtained at artificially increased pressure.Nevertheless, it is preferred that the impregnated materials be hardened by Er heat in closed vessels in which the pressure can be increased by any known means as desired. This achieves rapid heating and enables relatively high temperatures to be used without the risk of some of the reactants being lost through evaporation during the earlier stages of the reaction and before the conversion into the non-volatile product has occurred . 6ο patent applications: ι. Process for impregnating fully porous materials, such as wood, etc., characterized in that these substances are mixed with formaldehyde and phenols treated and the. Condensation of both components in the one to be impregnated Substances causes. 2. An "embodiment of the method. According to claim i, characterized in that that the mixture of formaldehyde · and phenols a partial condensation subjects, introduces the still liquid mass into the substances to be impregnated and then the condensation ends in these. 3. An embodiment of the method. " / jjach claims 1 and 2, characterized in that that the condensation of formaldehyde and phenols in the to be impregnated Substance is guided until the product is infusible and has become insoluble. 4. An embodiment of the method '85 according to claim 3, characterized in that the condensation of formaldehyde and phenols in the substance to be impregnated is effected with simultaneous application of heat and pressure. _go .5. An embodiment of the method of claim τ to 4, characterized in that, they are dehydrated by the addition of salts in Wassercntzichettdcr dem'Fülle be -in which used to prepare the condensation products of formaldehyde and phenols hydrous g $ Ausgangsmaterialicn. ■ Supplementary sheet to patent specification 231148 ■ CLASS 38h GROUP 2 The claim ι has been partially declared null and void by a legally binding decision of the Reich patent dated March 2 , 1916, because it has been restricted as follows: .., '.'. '■:' .. ·. · '. . ■■ '. · ■'. ' :. ·. "' Procedure for impregnating wood and other porous lumpy materials, thereby characterized that these substances with a mixture of formaldehyde and Treated phenols and the condensation of both components in the one to be impregnated Substances causes. ;.