NO843487L - WATER-DELIVERABLE CONCENTRATE, WATER AGENT AND PROCEDURE FOR TREATMENT OF TREE - Google Patents

Abstract

1. A water-dilutable concentrate or an aqueous composition for treating wood, containing - an organic binder which dries in air with the aid of a siccative, which is rendered water-soluble with the aid of a salt-former and the macromolecules of which are based on an unsaponifiable hydrocarbon chain, - optionally one or more water-insoluble, organic woodprotecting agents and/or one or more water-soluble woodprotecting agents, and - optionally additives conventional in the impregnation and coating industries, pore-closing additives being excluded, characterised in that - the binder is one or more carboxylated 1,3-(cyclo)diene polymers having an acid number of 50 to 250 [mg KOH/g], an (average) content of olefinic double bonds corresponding to an iodine number of >= 200 [g iodine/100g] and a relative molecular weight (Mn ) of 500 to 5000, provided that if more than one polymer is present none of them has an iodine number of < 100, and - the carboxyl groups of the binder are partially or completely neutralised with the aid of a base selected from alkali metal hydroxides, alkali metal carbonates, alkali metal bicarbonates, ammonia, lower molecular weight water-soluble monoamines which do not inhibit air drying, and their mixtures, so that the pH value of the treating composition is 6 to 11.5, the strength and amount of base (degree of neutralisation) on the one hand and the structural parameters governing the water-solubility on the other hand being so related to one another that the binder is water-soluble or is present in dissolved form, as the case may be.

Description

The application concerns a water-dilutable concentrate, an aqueous agent and a method for treating wood according to the preamble in claim 1 or 3.

By wood is meant all species of wood and wood materials such as

has an open-pore structure that is available for the application methods used in the impregnation technique. Wood materials are e.g. plywood, furniture boards and chipboards.

Wood preservatives are wood-protecting biocides that do not inhibit air drying, primarily those with insecticidal and/or fungicidal action.

The invention relates to impregnation technology and related techniques. The aim is to achieve effective and lasting tree protection. In this context, it is considered important to transport the binder or the binder and the wood preservative in sufficient concentration into the parts of the wood to be protected (penetration), and to fix the agents in this place. Under certain circumstances, a decorative effect can also be achieved in the surface of the wood.

The invention does not relate to varnishing techniques for wood.

When varnishing, the aim is to have a decorative function in the wooden surface and in any case no depth effect (coating agents for application to the surface of wood).

The state of the art in the area of the invention belongs

what is known from DE-C 28 38 930 and the Norwegian generally available patent applications 81 2295 and 83 0081 (in the area of the invention there is also a Norwegian patent application no. 83 1346). Wood that has been treated with the agents described there, and that contains common drying agents (siccatives), exhibits a drying behavior during air drying that does not always satisfy the requirements set in practice. The drying has usually only progressed sufficiently after 24 hours for impregnated wood to be stored in the open and exposed to the prevailing weather conditions without having to count on washing out the binder or binder and wood preservative.

The invention is based on the task of overcoming this deficiency and obtaining a water-dilutable concentrate, an aqueous agent and a method for treating wood which allows the person skilled in the art to significantly reduce the drying time by air drying. This task is surprisingly solved in the manner indicated in the patent claims.

I. The polymers to be used according to the invention,

can be copolymers of (a) one or more 1,3-(cyclo)dienes such as 1,3-butadiene and cyclopentadiene or (b) one or more I,3-(cyclo)dienes and one or more copolymerizable alkenes such as styrene or (c) the monomers according to (a) or (b)

and furthermore one or more (di)esters of o,ft-alkenically unsaturated (di)carboxylic acids on the one hand and one or more cx,ft-alkenically unsaturated (di)carboxylic acids and/or one or more of the half-esters of the dicarboxylic acids on the other hand.

The carboxylic acids are e.g. acrylic and methacrylic acid. The dicarboxylic acids are e.g. maleic and fumaric acid. Preferred alcohol components in the esters are monovalent C₁-C₂-alkanols which optionally contain ether groups, or mixtures of such alkanols.

The polymers are known in principle and can be produced

according to known methods.

II. The polymers are preferably adducts of the base polymers indicated below and an acid component from the group consisting of 0(,(1-alkenically unsaturated dicarboxylic acids, their anhydrides and half-esters and mixtures and optionally one or more diesters of the dicarboxylic acids.

The base polymers are homopolymers of 1,3-(cyclo)dienes or copolymers of 1,3-(cyclo)dienes or of one or more 1,3-(cyclo)dienes and one or more copolymerisable alkenes. They may be modified by isomerization, partial cyclization or partial hydrogenation.

The monomers which are mentioned for example in connection with the first group of polymers (see I) also apply, for example, to the base polymers and the acid components of the adducts.

The adducts containing ester groups can be obtained directly or indirectly, i.e. by subsequent partial esterification of the adducts.

Preferred alcohol components for subsequent esterification are saturated or alkenically or acetylenically unsaturated, monovalent C₁-C₆-alcohols which optionally contain ether groups, or mixtures of such alcohols. The adducts which are modified by subsequent esterification are preferred. They preferably have an acid number of 50-125 (mg KOH per g).

The polymers are known in principle and can be prepared according to known methods (DE-C 28 38 930).

Common wood preservatives can be used as wood preservatives.

Suitable non-water-soluble wood preservatives are e.g. 2,5-dimethylfuran-3-carboxylic acid-N-methoxy-N-cyclohexyl-amide, tributyltin benzoate, tributyltin naphthenate, y-hexachlorocyclohexane, pentachlorophenol, pentachlorophenol laurate, 2-mercapto-benzthiadiazole-2, 2-(methoxycarbonylamino )-benzimidazole, N,N-dimethyl-N<1->phenyl-N'-(fluorodichloromethylthio)-sulfamide, N,N-dimethyl-N'-p-toly1-N'-(fluorodichloromethylthio)-sulfamide, car- bamate, dithiocarbamate, phosphoric acid esters, phosphonic acid esters, thiophosphoric acid esters, dithiophosphoric acid esters, thiophosphoric acid esters, o-phenylphenol, hydroxyquinoline derivatives, endosulfan, pyrethroids and 3-iodo-2-propynyl-butyl-carbamate.

Suitable water-soluble wood preservatives are e.g. alkali fluorides, fluorosilicates such as MgSiF^, alkali arsenates, borates and salts of lead, tin, cadmium, nickel, cobalt, manganese, copper, mercury, zinc and chromium, as well as (C^2-C-^-alkyl)-benzyl-dimethylammonium chloride.

Common additions are e.g. pigments, anti-tan agents, stabilizers, surfactants, viscosity regulators and water-compatible solvents.

Suitable water-compatible solvents are e.g. isopropanol, butanols, diacetone alcohol, alkyl cellosolves and demethyl ethers of glycols. The solvents or mixtures thereof can be used in quantities of up to 100 parts by mass, calculated on 100 parts by mass of binder. They are preferably used in amounts of 5-50, and most preferably 10-40 parts by mass.

Pore-closing additives that should not occur are understood to mean such additives which, due to their nature and_ their concentration in the treatment agent, will lead to a closing of the wood's pores upon application and thereby significantly hinder the intended depth effect of the treatment agent.

Additives of the kind described can be mixed in

in quantities that are common in practice. The type and quantity of such additives always depend on the material to be treated at any given time, its intended use and the treatment method and are easy to determine with a few indicative tests.

As the binders to be used in the treatment agents according to the invention are air-drying, it is not usually necessary to add additional resins as cross-linking agents. Of course, additional binders can be used at the same time which (possibly during heat treatment) act as cross-linking agents, e.g. water-soluble or dispersible amino plastics or phenolic resins, provided that the effect sought by the invention is not significantly reduced.

The treatment agents according to the invention usually have a binder content of 1-40, preferably 5-30, mass percent and can be applied by all known methods according to the state of the art (see DIN 68 800, sheet 3). In this connection, the achievable protective effect - as is known to the person skilled in the art - is closely linked to the treatment method.

Particularly effective is an impregnation method where the wood, possibly under pressure or vacuum, is subjected to a full impregnation.

The following examples serve to illustrate the invention. Parts shall mean parts by mass and percentage shall mean percent by mass unless otherwise stated.

Examples

Base polymer 1

Polybutadiene with the following characteristics:

Mn (vapor pressure osmometrically determined in chlorobenzene): approx. 1700; iodine value (g iodine per 100 g) (DIN 53 241): 445;

double bond distribution (IR analysis) in percent, calculated on the total double bonds: 73 cis and 25 trans (in structural units obtained by 1,4-polymerization of 1,3-butadiene); 2 vinyl

(in structural units obtained by 1,2-polymerization of 1,3-butadiene);

viscosity (Pa.s) (DIN 53 214, 20°C): 0.8.

Base polymer 2

Polycyclopentadiene with the following characteristics:

iodine number (g iodine per 100 g): 170-180;

melting point: approx. 145°C;

color (Gardner): 5

density (g/cm 3 ): 1.1-1.2.

Preparation of binder 1

1200 parts of base polymer 1 and 300 parts of maleic anhydride (MSA) were heated in the presence of 1.5 parts of acetylacetone and 1.6 parts of the commercially available antioxidant N,N'-diphenyl-p-phenylenediamine under a nitrogen atmosphere in 1 hour at 180°C and then for 3 hours at 190°C. The MSA adduct obtained contained ^ 0.1% free MSA and had an acid number of 218 mg KOH per g. (titrated in pyridine/water.)

Production of binder 2

233 parts of base polymer 1, 58.3 parts of base polymer 2, 1.9 parts of copper naphthenate and 0.1 parts of acetylacetone were heated under a nitrogen atmosphere to 120-140°C until a homogeneous mixture was obtained. After adding 63.9 parts MSA

was heated there during 1 hour under rising temperature to 190°C, after which the reaction mixture was kept at this temperature for 3 hours. The reaction mixture was then cooled to 130°C, pre-cut with 58.7 parts of ethylene glycol monoethyl ether (ethyl glycol) and held at this temperature for 1 hour. The half-ester obtained had an acid number of 83 mg KOH per g.

Preparation of concentrate 1 and treatment agent 1

The subsequent ingredients were mixed in the order indicated at 40-60°C.

1 part of the concentrate 1 obtained as a clear solution was mixed with 4 parts of water. The treatment agent 1 obtained was a clear solution and had a pH value of 9.5. The condition of the concentrate 1 and the treatment agent 1 was almost unchanged after one month of storage in a closed container at approx. 60°C.

Preparation of treatment agent 2

The following ingredients were mixed in the order indicated at room temperature.

The treatment agent 2 obtained was a clear solution and had a pH value of 10.1 g. Its condition was almost unchanged after storage for approx. 1 month in a closed container at approx. 60°C.

The treatment agents 1 and 2 according to the invention showed a very good shelf life during storage which was not inferior to the durability of the treatment agents according to the state of the art described above.

Attempts to characterize the air drying

The drying behavior during air drying of wood treated according to the invention, compared to the state of the art, is determined by the dust drying times for coating the treatment agents on glass plates. Here, treatment agents 3 and 4 according to the invention were used and, for comparison, treatment agent A according to DE-C 28 38 930. These treatment agents had the following recipes:

The treatments were applied to the glass plates with a 100

p saliva and stored at 20°C. The dust drying times were determined in accordance with DIN 55 934 and are indicated in the table below.

Similar results are obtained if treatment agents 3, 4 and A are added with normal amounts of wood preservative.

Claims (3)

1. Water-dilutable concentrate and aqueous agent for the treatment of wood, containing - an organic binder that is air-dried with desiccants and dissolved with salt formers, which is based on macromolecules with an unsaponifiable carbon chain, - possibly one or more non-water-soluble organic wood preservatives and/or one or more water-soluble wood preservatives and - possibly in the impregnation and varnishing technique common additives, since pore-closing additives do not occur, characterized by that - the binder is one or more carboxylated 1,3-(cyclo)diene polymers with an acid number of 50-250 (mg KOH per g), an (average) content of alkenic double bonds corresponding to an iodine number of - 200 (g iodine per 100 g) and a relative molecular mass (M ) of 500-5000, none of the polymers used having an iodine number of less than 100, and - the carboxyl groups in the binder are completely or partially neutralized with a base from the group consisting of alkali hydroxides, alkali carbonates, alkali hydrogen carbonates, ammonia, low-molecular water-soluble monoamines that do not prevent air drying, and their mixtures, so that the pH value of the treatment agent is 6- 11.5, as the base strength and the amount of base (the degree of neutralization) on the one hand and the structural parameters that determine the water solubility on the other hand, are coordinated in such a way that the binder is water-soluble resp. available in solution. 2. Water-dilutable concentrate and aqueous agent for treating wood as specified in claim 1, characterized in that - the binder is one or more carboxylated 1,3-(cyclo)diene polymers that contain adjacent ester groups and have a relative molecular mass of 800-3000, and - the carboxyl groups in the binder are completely or partially neutralized with a base, so that the pH value of the treatment agent is 6.5-10.5. 3. Procedure for treating wood with an aqueous treatment agent using the known methods in impregnation technology, characterized in that an agent as stated in claim 1 or 2 is used as a treatment agent.