FR2661356A1 - TRANSPARENT IMPREGNATION AGENT FOR WOOD AND METHOD FOR MANUFACTURING THE SAME - Google Patents

Abstract

The invention relates to an impregnating agent for wood, in liquid form, containing a solvent and a biocide. The invention extends to a process for the manufacture of this agent. The problem to be solved is to create a transparent impregnating agent free of water, which can be applied by painting, penetrates well into the wood and gives a natural color finish. The impregnating agent is characterized in that it contains, as the main component of the drying substance, isocyanate-modified linseed oil and, in addition, a drying mixture, and that the solvent consists mainly of aliphatic liquids free from hydrocarbons. The process consists in adding to the solvent while stirring, and in order, the linseed oil modified with isocyanate, the drying mixture, the biocide and optionally the agent against the formation of a skin. The invention applies to the protection of wood.

Description

Transparent impregnating agent for wood and

process for its manufacture.

  The subject of the present invention is a liquid and transparent impregnating agent for wood. It also relates to a process for the manufacture of this agent.

  liquid form; it contains a solvent and a biocide.

  Wood impregnating agents are already known They are used to protect the wood against harmful actions of the environment as well as to prolong its life. In particular, we strive to protect against the attack of fungi and bacteria from putrefaction, algae and animals such as insects As a rule, the impregnating agents are systems

  liquids, which may also contain water.

  An ideal wood preservative must have a lasting toxic action against pests, yet not toxic to humans and domestic animals. It must not attack metals; it must also penetrate as easily as possible, even in previously untreated wood. It must not be washed off under the action of rain and the like and must be as economical as possible. An important difficulty is to penetrate the agent into the wood. As a result, pressure vessel processes are currently used in which the pre-dried wood is alternately subjected to overpressures and depressions in a closed vessel containing the pressure. impregnating agent. These methods are not applicable, or are very expensive, to finished wooden objects and in particular to wooden articles of civil engineering Painting processes which are also already known, have the disadvantage that wooden objects must firstly, to receive a printing layer before an impregnating agent, to be dried for a long time, then to be provided with another surface layer. To this is added the fact that the carbolineum, previously used as an agent for effective impregnation, can no longer be used today because of its toxicity. The problems described above and the drawbacks of current solutions in the wood preservation sector are dealt with in detail in the "Chemie-Lexikon" (chemistry lexicon) of RÈmpp, for example in the sixth edition of 1966,

Volume II, p 2758 to 2762.

  The problem of the invention was to create a wood impregnating agent water-free, acting in particular as a fungicide and algicide, which can be applied by painting, penetrating better into the wood than known agents, but acting at the same time to give a surface finish, that is to say making superfluous the application of a varnish, a lacquer or a surface layer In addition, this agent must better protect the wood against the action of water, ultraviolet rays, solar radiation and cold It must also be compatible with the environment, including

included during its manufacture.

  To this end, the invention relates to an impregnating agent of the above type, characterized in that it contains, as the main component of the drying substance, isocyanate-modified linseed oil and, in addition, , a siccative mixture, and in that the solvent consists mainly of

  aliphatic liquids free of hydrocarbons.

  Particular embodiments are

described below.

  As was furthermore noted with surprise, the order of addition of the components of the wood impregnating agent according to the invention during manufacture is decisive in that the best results are obtained for a given order. Accordingly, the invention furthermore relates to a method for producing the wood impregnating agent, which process is characterized in that by stirring the previously deposited solvent, one after the other is order the following components: 25 parts isocyanate-modified linseed oil, 60% white spirit, 0.04 to 0.12 parts by weight of drying mixture, relating to the metal, 0, 5 to 1.2 parts of biocide, 0.3 to 0.8 parts of a component

against the formation of a skin.

  We will now identify more precisely the individual constituents of the agent

  impregnation according to the invention.

  The main component ("body") of the solvent-free phase of the agent is a drying chemical based on linseed oil, which is normally known only for surface layers. An especially suitable product is an "URADUR F 77" which is supplied as a 60% solution in white spirit by the company DMS.

Resins.

  To ensure a better hardening of this product, which dries well in the air but whose hardening must take place by itself inside the wood where the air can not arrive, we add the known drying metal salts following:

  naphthenate, octoate, linoleate, resinate and the like.

  A product which has proved to be particularly suitable is a mixture of manganese, calcium and zirconium compounds, this mixture being new and causing a surprisingly good and rapid drying. Suitable driers of this group, ie say the different metal derivatives, can be obtained under the commercial designation "Nuodex" at

  URAI Spa Company, Assago, Italy.

  As solvents, the impregnating agent for wood according to the invention contains, apart from the white spirit of the modified linseed oil, only aliphatic compounds containing oxygen. The solvents chosen seem to be responsible for the good penetration of the agent according to the invention in the wood In addition, they are much more compatible with the environment than hydrocarbons A mixture of a lower glycol ether whose boiling point is between 100 and 150 C with an alcoholic ester whose boiling point is between 180 and 260 ° C is proven It may be a mixture comprising a glycol monoester as the main constituent of the mixture, and a glycol monoether as a secondary constituent of such glycol ethers are, for example, the "Dowanol PM" of

  the Dow Chemical Company (propylene glycol

  monomethyl ether) as well as ethylene glycol methyl ether and ethylene glycol ethyl ether as well as in particular butyldiglycol ether (butylcarbitol). The alcoholic esters are, for example, monoformate and glycol acetate. The "Texanol" product of Eastman

  Chemical Company has a proven track record.

  As a biocidal substance, the wood impregnating agent according to the invention preferably contains a sulfamide derivative active against fungi, algae, of the penicillium type, resistant to light, nonvolatil, and not impeding the drying of the Derivative oil derivative N, N-diaryl N'-aryl N '- (trihalogenomethylthio) sulphamide is preferably used. As dyestuff, the materials of the range are used under the best conditions.

"Sicoflush" (BASF).

  The impregnating agent for wood according to the invention contains as a rule, but not necessarily, a leveling product, for example aldoxines or ketoximes to prevent the formation of a skin Suitable oximes are, for example, butyraldoxime Methyl ethyl ketoxime and cyclohexanone oxime Other suitable additives are rheological additives such as, for example, layered and modified organic silicates ("Bentone SD 1" from Kronos Titan GmbH, Leverkusen, Germany) as well as other usual additives. such as wetting agents and dispersing agents, flavorings etc. The particularly suitable wood impregnating agent composition is as follows, indicated by parts by weight: Isocyanate-modified linseed oil: (at 60% in the white spirit) Drying mixture (each time referred to metal): Biocide: Solvents, ethers and alcohol esters including 1 to 5 parts of glycol ether, the rest being alcohols oliques: In addition, if desired: Agent against the formation of a skin at 35

0.04 to 0.12

0.5 to 1.2

at 75

0.3 to 0.8

  For the practice of the process according to the invention, the solvent is first available in a stirring tank, the dissolution of

  the modified linseed oil and add the siccatives

  As well as the biocide Among the additives chosen, the agent is added to the formation of a skin immediately after the drying agents. During the formation, the stirring is of course carried out constantly. The best work is carried out at the normal room temperature; a load of about 100 kg is complete

in about 20 to 30 minutes.

  The impregnating agent is further distinguished by an increased shelf life, generally from about 8 to 12 months. For the application, the surface of the mechanically cleaned wood is coated or sprayed with the liquid agent, allowed to dry, for example for 24 hours and the surface is provided with a second layer of the same agent. A third layer is very rarely needed The wood is then impregnated for its preservation and also has its natural color, for example walnut, larch, mahogany, teak etc without another additional layer such as dyeing

etc. is necessary.

  An example will explain more

clearly the invention.

Example

  In an agitator vessel equipped with a venting vent and having a useful capacity of about liters, 3 kg of "Dowanol PM" (propylene glycol methyl ether, boiling point 120 ° C.) and 64.5 kg of " Texanol "(alcohol ester, boiling point 2440 ° C.) With stirring, the following products are added progressively: 30 kg of" Uradur F-77 "(at 60% in the white spirit), 0.2 kg of drying agent at manganese (6% Mn), 0.6 kg of calcium scavenger (4% Ca), 0.4 kg of zirconium scavenger (12% Zr), 0.5 kg of Exkin 2 (methyl ethyl ketoxime) and 0 , 8 kg of

biocide.

  After stirring for 30 minutes, a transparent impregnating agent having the properties described above is obtained, this agent penetrating very well into

wood.

  As already mentioned, an additional surface treatment of the impregnated wood is not necessary. This treatment can, however, be carried out if desired. The impregnation described above does not harm different or similar layers or coatings.

Claims (5)

  1) Transparent impregnating agent in the form of a wood liquid, containing a solvent and a biocide, characterized in that it contains, as the main component of the drying substance, linseed oil modified with the isocyanate and, further, a drying mixture, and in that the solvent consists mainly of aliphatic liquids free of hydrocarbons. 2) impregnating agent according to claim 1, characterized in that the siccative mixture is a mixture based on   manganese, calcium and zirconium.   3) Impregnating agent according to one   any of claims 1 and 2, characterized in that   it also contains an agent based on oximes against the formation of a skin.   4) Impregnating agent according to one   any of claims 1 to 3, characterized in that   that it contains as a biocide an N, N-diaryl   N'-aryl N '- (trihalogenomethylthio) sulfamide.   ) Impregnating agent according to claim 4, characterized in that its composition, by parts by weight, is the following: a) 25 to 35 parts of isocyanate-modified linseed oil, 60% in white spirit , b) 0.04 to 0.12 parts of the drying mixture relative to the metal, c) 0.3 to 0.8 parts of agent against the formation of a skin, d) 0.5 to 1.2 parts of biocide, e) 55 to 75 parts of solvent.   6) Impregnating agent according to one   any of claims 1 to 5, characterized in that   that the solvent is a mixture of alcoholic esters and glycol ethers.   7) Impregnating agent according to claim 6, characterized in that the main constituent of the mixture is a glycol monoester and the secondary constituent element is a glycol monoether. 8) Process for the manufacture of the impregnating agent according to claim 5, characterized in that stirring the component (e) placed beforehand is added one after the other and in the order indicated in claim 5 components (a) to (d) and dissolve or disperse them before adding the next component.