PT100707B - COMPOSITIONS FOR THE CONSERVATION OF WOOD AND OTHER CELLULOSE MATERIALS, AND PROCESS FOR THE TREATMENT OF WOODS OR CELLULAR MATERIALS USING THESE COMPOSITIONS - Google Patents

Abstract

PCT No. PCT/GB92/01427 Sec. 371 Date Apr. 4, 1994 Sec. 102(e) Date Apr. 4, 1994 PCT Filed Aug. 3, 1992 PCT Pub. No. WO93/02557 PCT Pub. Date Feb. 18, 1993The instant invention concerns a wood preservative composition comprising a synergistically effective amount of (a) a cuprammonium compound and (b) tebuconazole to preserve wood.

Description

DESCRIPTION

The present invention relates to compositions for preserving wood and other cellulosic materials.

It is already widely known to use biocidal metal ions in compositions for wood conservation. There are also many compounds containing a triazole group, which are known to have biocidal properties.

According to the present invention there are preservation compositions for wood and cellulosic products characterized by comprising a metallic compound

C.R.

biological biocide and a fungicidal compound containing a triazole group, fungicide containing the triazole group is at least 1: 2.5; the particular exceptions 1.320% by weight of copper nitrite 5H ₂ 0, 0.400% by weight of sodium heptonate, dio, surfactant mixture in xylene and 95.762% (II) the composition of formula:

in which the weight ratio of metal atom: compound with from (I) the composition (a) containing sodium, 1,190% by weight of borate acid sulfate, 0.625% in 0.390% by weight of hydroxide

0.012% by weight of tebuconazole, 0.391% by weight of (b) containing 0.00025% by weight of water, and a one-component

formulates a compound of

CHq - ch - nh - cs - s \

Zn / ch ₂ - nh - CS - s

2.525% by weight of dimethylformamide, 0.006313% by weight of an alkyl-aryl-polyglycolic ether, the rest being water.

We have found that the compositions according to the invention have advantageous properties: in particular, the metallic compound and the fungicidal compound containing the triazole group (hereinafter referred to as the triazole compound) have been found to exhibit synergistic fungicidal activity.

Note that the metal compound can be present in a form such that the metal ions are free in the solution, or they can form part of a complex. Similarly, the triazole compound can be free in solution or it can be present in the form of a salt or a complex. For example, the triazole compound could be present in the form of a complex with part of the biocidal metal ion.

The compositions according to the invention can be used for the treatment of substrates, such as wood or other cellulosic materials (such as cotton, tow, cables and rigging). For convenience, the invention will now be described with reference to wood treatment, but it should be noted that other cellulosic materials can be treated similarly.

Metallic compound can be a compound of any metal with biocidal activity, including copper, aluminum, manganese, iron, cobalt, nickel, zinc, silver, cadmium, tin, antimony, mercury, lead and bismuth. These can be used either alone or in mixtures. Preferred metals are copper and zinc, used alone, in combination with one another or with one or more of the metals listed above. The most preferred metal is copper, particularly Cu (II) ion.

The triazole compound can be any compound that contains a triazole group and that has biocidal activity. The triazole compound preferably contains the triazole group.

triazole compound is preferably chosen from the compounds of formula (A):

in which

R ^ represents an alkyl group having 1 to 5 carbon atoms, straight or branched chain (for example, t-butyl) and

R ₂ represents a phenyl group optionally substituted by one or more substituents chosen from halogen atoms (eg chlorine, fluorine or bromine) or alkoxy groups having 1 to 3 carbon atoms (eg methyl) alkoxy with 1 to 3 atoms carbon (for example, methoxy), phenyl or nitro.

A particularly preferred compound of formula (A) is tebuconazole:

alpha- [2- (4-chlorophenyl) -ethyl] -alpha- (1,1-dimethylethyl) -1H-1,2,4-triazole-1-ethanol.

As an alternative, the triazole compound is advantageously chosen from the compounds of formula (B):

in which

Rg is defined as R ₂ above, and

R ₄ represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, straight or branched chain (for example, n-propyl).

Particularly preferred compounds of formula (B) are:

propiconazole (1 - [[2- (2,4-dichlorophenyl) -4-propyl-1,3-dioxolane-2-yl] -methyl] -1H-1,2,4-triazole) and azaconazole (l- [ [-2,4-dichlorophenyl) -1,3-dioxolane-2-yl] -methyl] -1H-1,2,4-triazole).

hexaconazole and diphenaconazole are examples of other triazole compounds that can be used in the compositions according to the invention.

The compositions can contain more than one triazole compound, for example, they can contain tebuconazole and propiconazole, or a mixture of tebuconazole, propiconazole and azaconazole.

We have found that the biocidal metal can be advantageously incorporated into the composition in the form of inorganic salts of the metal ion, for example in the form of the carbonate, sulphate, chloride, hydroxide, borate, fluoride or metal oxide. Alternatively, the metal can be used in the form of the metal salt of a simple organic compound, for example in the form of a salt of a carboxylic acid, such as a metal acetate. Thus, it has been found that biocidal triazole compounds exhibit synergistic properties when the metal ion is present in the form of these simple salts and it is therefore not necessary to add the metal ion in the form of a salt, or complex, of a rather organic compound. more complex that itself has biocidal properties.

The optimal weight ratio of the metal ion to the triazole compound varies depending on the particular material or product to which the composition is applied, and also depending on the type of organism against which protection is sought. Preferably the weight ratio of metal to triazole compound is less than 1000: 1, for example less than 750: 1. More preferably the weight ratio of metal:

* triazole compound should be between 750: 1 and • 1: 1, particularly preferably between 500: 1 and 2: 1; much

preferably, said weight ratio is between 50: 1 and 5: 1, especially about 25: 1.

The concentration required for a conservation treatment depends on the metal-to-triazole compound ratio chosen, the metal chosen, the treatment method employed, the species of wood, the level of protection required and the nature and quantity of any other biocides present . The required levels can be quickly determined by those skilled in the art. In general the required metal level will be in the range of 0.01 to 5% and the level of the triazole compound will be in the range of 25 ppm to 1.0%. The preferred range for waterborne treatments is to have a metal concentration of 0.1 to 5% and a level of triazole compound from 50 ppm to 5000 ppm.

The compositions according to the invention can, if desired, additionally contain the nitrite ion. As an alternative, there may be advantages associated with the omission of the nitrite ion from the composition, for example, by omitting the nitrite ion, the formation of certain harmful gases is avoided.

The compositions of the present invention advantageously contain a quaternary ammonium compound or a tertiary amine salt which are active as biocides. These compounds assist in the formation of emulsions of the triazole compounds in aqueous solutions of the biocidal metal ion. Compositions containing quaternary ammonium compounds or tertiary amine salts can form microemulsions which are particularly useful in the treatment of wood. In addition, the presence of these compounds may mean that additional organic solvents are not required to solubilize the triazole compound. In addition, the quaternary ammonium compounds and the tertiary amine salts are themselves biocides and thus contribute to the overall biocidal activity of the composition. These compounds also improve the penetration of the biocidal metal ion and the triazole compound into the wood.

The composition according to the invention can contain water as a solvent, or an organic solvent or a mixture of solvents. The formulations can be prepared as concentrates to be diluted in the treatment facility, or alternatively the formulations can be prepared in the form of diluted solutions for treatment. Eventually, separate solutions of the biocidal metal ion and the triazole compound may be prepared, for example in the form of two concentrates intended to be mixed before or after dilution.

Appropriate formulations can be prepared, for example, by preparing aqueous solutions of metal ion complexes and subsequently adding an emulsified formulation of the triazole compound. Complexing agents suitable for the metal ion may, for example, be polyphosphoric acids, such as tripolyphosphoric acid, ammonia, water-soluble amines and alkanolamines capable of complexing with biocidal cations; aminocarboxylic acids such as glycine, glutamic acid, ethylenediamino-tetraacetic acid, hydroxyethylenediamino-triacetic acid, nitrilotriacetic acid and N-dihydroxyethylglycine; polymeric compounds containing groups capable of complexing with metal cations, such as polyacrylic acids; hydroxycarboxylic acids such as tartaric acid, citric acid, malic acid, lactic acid, hydroxybutyric acid, glycolic acid, gluconic acid and glucoheptonic acid; phosphonic acids, such as nitrilotrimethylene-phosphonic acid, ethylenediamino-tetra- (methylene-phosphonic) acid, hydroxyethylidene-di phosphonic acid. Whenever complexing agents are acidic in nature, they can be used either in the form of free acids or in the form of their alkali metal or ammonium salts. These complexing agents can be used either alone or in combination with each other. Suitable surfactants for triazole compounds include, for example, cationic, non-ionic, amionic or amphoteric surfactants.

Suitable formulations can also be prepared for example by adding an emulsified formulation of the triazole compound to an aqueous solution of the metal salt, such as copper sulfate or zinc acetate. For

high metal ion to azole ratios, the solubility of the azole may be sufficient to disperse the azole in the formulation using an appropriate co-solvent.

Alternatively, formulations can be prepared using only organic solvents. To prepare these formulations, a biocidal metal salt of a carboxylic acid (for example decanoic or octanoic acid) is previously prepared and it is dissolved in an appropriate organic solvent to form a concentrate. The triazole compound can then be added directly to the concentrate, or to a solution diluted with an appropriate solvent, such as an ester, alcohol, ester-alcohol, aliphatic or aromatic hydrocarbon, glycolic ether, glycol or ketone.

Concentrated formulations containing organic solvents may optionally be mixed with water to form an emulsion that can be stabilized with surfactants if necessary.

The compositions according to the invention may optionally contain other additives conventionally employed in wood preservation, such as water repellents, colored additives, viscosity modifiers or corrosion inhibitors.

The compositions according to the invention can contain other organic compounds including fungicides, insecticides and bactericides. These organic compounds include carboxylic acids, such as naphthenic acids and branched-chain aliphatic acids, and their metallic salts, such as copper and zinc naphthenates, phenols and substituted phenols, such as orthophenyl-phenol and its alkali metal salts or ammonium; polyhalogenated phenols such as pentachlorophenol or tribromophenol, and their alkali metal or ammonium salts; quaternary ammonium salts and tertiary amine salts, such as didecyl-dimethyl-ammonium chloride, octyl-decyl-dimethyl-ammonium chloride, dyl-dimethyl-benzyl-ammonium chloride, dodecyl-benzyl-trimethyl-ammonium chloride , dodecyl-dimethylamine acetate, dodecyl-dimethylamine lactate, dodecyl-dimethylamine salicylate, didodecyl-methylamine chloride;

isothiazolone derivatives, such as 4,5-dichloro-2- (n-octyl) -4-isothiazoline-3-one or 2-methyl-4-isothiazoline-3-one, 2-n-octyl-4-isothiazoline 3-one and mixtures of these compounds and other related compounds;

sulfamide derivatives, such as N, N-dimethyl-N-phenyl- (N-fluoro dichloro-methylthio) -sulfonamide, N, N-dimethyl-N-tolyl-N- (dichloro fluoro-methylthio) -sulfamide;

azois, such as imidazole;

MBT (methylene-bis-thiocyanate);

IPBC (3-iodo-2-propenyl-butyl carbamate); carbendazim and chlorothalonil;

N-nitrosophenylhydroxylamine and N-nitroso-cyclohexyl-hydroxylamine, either in the form of their metal salts or as metal chelates;

pyrethroid insecticides, chosen from the group consisting of cyano- (4-fluor-3-phenoxyphenyl) -methyl-3- (2,2-dichloroethyl) -2,2-dimethyl-cyclopropanecarboxylate, (3-phenoxyphenyl) -methyl -3- (2,2-dichloroethyl) -2,2-dimethyl-cyclopropanecarboxylate, cyano- (3-phenoxyphenyl) -methyl-2- (4-chlorophenyl) -3-methylbutyrate, and mixtures thereof;

organo-phosphorus insecticides, carbamates and organochlorines, such as lindane.

Other elements with biocidal activity, such as boron, may also be present in any form, for example as boric acid, such as boron or boron esters, and also fluorides and silicofluorides.

Particularly preferred compositions according to the invention comprise copper (II) ion, a triazole compound which is tebuconazole or propiconazole, and an alkanolamine, as well as borate ion and / or a quaternary ammonium compound or a mixture of compounds of quaternary ammonium.

According to another aspect of the invention there is disclosed a process for the treatment of a substrate of the type previously defined, which comprises the application to the substrate of a composition as defined above. Also included in the scope of the invention is a process for treating a substrate of the type previously defined, which comprises applying to the substrate the composition (b) defined above.

Those skilled in the art will be perfectly familiar with the various methods of treating substrates with aqueous solutions. For example, the compositions according to the invention can be applied to the wood by dipping, spraying, prolonged dipping, by brushing or by vacuum and / or by impregnation under pressure. Other types of substrates can be treated by similar methods.

The following non-limiting examples illustrate the present invention in more detail.

EXAMPLES

The compositions of examples 1 to 3 can be prepared by adding an emulsified formulation of the triazole compound to an aqueous solution of a metal complex.

Example 1 Concentrate formulation; relationship metal for azole 25: 1 % w / w basic copper carbonate 10.9 monoethanolamine 23.1 Boric acid 16.9 tebuconazole 0.24 xylene 3.76 treatment oil 4.00 anionic / non-ionic emulsifier 1.00 Water 40.10 Example 2 Ready-to-use solution; metal ratio for azole 10: 1 % w / w copper sulfate pentahydrate 1.18 lactic acid 2.13 sodium nitrite 1.31 Boric acid 0.79 Ammonium hydroxide 0.57

»<.

tebuconazole c ipermetr ina 0.03 0.05 methyl-dioxitol 0.64 anionic / non-ionic emulsifier 0.08 Water 93.22. Example 3 Ready-to-use solution; metal ratio for azole 5: 1 % w / w basic copper carbonate 0.55 Ammonium hydroxide 0.65 ammonium bicarbonate 0.33 propiconazole 0.06 naphthenic acid 0.15 anionic / non-ionic emulsifier 0.21 methyl-dioxitol 0.48 Water 97,624.

Example 4 Ready-to-use solution; metal to azole ratio 5; 1

The compositions of examples 4 and 5 can be prepared by adding an emulsified formulation of the triazole compound to the aqueous metal ion solution.

% w / w

copper acetate 0.43 zinc acetate 0.84 tebuconazole 0.06 ester-alcohol 0.03 2-ethylhexanoic acid 0.03 treatment oil 0.03 anionic / non-ionic emulsifier 0.06 Water 98.52

Example 5 Ready-to-use solution; metal to azole ratio 30: 1% w / w copper sulfate pentahydrate 1.18 azaconazole 0.01 methyl dioxide emulsifier anionic / nonionic water

98.72.

Example 6 System of two packages% w / w

Packing A: copper carbonate 14.5 monoethanolamine 30.7 Water 54.8. % w / w Packaging B: tebuconazole 10 glycolic ester 50 2-ethylhexanoic acid 10 treatment oil 10 anionic / non-ionic emulsifier 20. The copper ratio for tebuconazole resulting from the package A and package B can vary from 1: 2.5 to 750: 1 parts by weight. Separate packages are to be mixed with each other in the work installation treatment and diluted with water. The examples 7 to 11 contain organic solvents. Example 7 Concentrate % w / w zinc versatate 15.0 tebuconazole 0.5 glycolic ether 10.0 white spirit 74.5 Example 8 Concentrate % w / w copper caprylate 25.0 tebuconazole 0.05 Shellsol A 74.75 permethrin 0.2.

Example 9 Concentrate % w / w copper acypetacs 15.0 hexylene glycol biborate 10.0 cypermethrin 0.1 tebuconazole 0.1 white spirit 74.8. Example 10 Concentrate % w / w azaconazole zinc octoate glycolic ether 50.0 1.0 49.0

Solution 11 Ready to use solution% w / w

copper versatate 5.0 propiconazole 0.01 permethrin 0.1 white spirit 94.89.

The compositions of examples 12 and 13 each contain a quaternary ammonium compound with biocidal activity. These compounds stabilize the triazole compound in the treatment solution obtained by diluting the concentrated compositions.

Example 12 Concentrate% w / w monoethanolamine19.23 basic copper carbonate7.27 benzalkonium chloride (50% active) 8.0 tebuconazole0.8 boric acid11,3.

Weight ratio Cu: benzalkonic chloride: tebuconazole 5: 5: 1.

Example 12 (a)

A concentrate with the same formulation as in example 12 was prepared, except for replacing monoethanolamine with ethylenediamine.

Example 13 Concentrate% w / w monoethanolamine 30.77 basic copper carbonate 14.50 didecyl dimethylammonium methyl sulfate 8.0 (50% active) propiconazole 0.32 weight ratio Cu:

didecyl-dimethylammonium methyl sulfate:

propiconazole 2: 1: 0.08.

Example 13fa)

A concentrate was prepared having the same formulation as in example 13, except that monoethanolamine was replaced with diethanolamine.

Synergistic action of mixtures formulated according to the invention toxic limit value for a particular biocidal compound and the concentration of the compound that is necessary to prevent the degradation (defined as> 3% mass loss) of a substrate by a target organism. Toxic limits are usually expressed by two concentrations, determined experimentally, which cover the test pass / fail point. The toxic index is the midpoint of these two values. Whenever a conservation composition contains two biocidal compounds in a given relationship, the toxic index is the minimum estimated concentration of each biocide necessary for the effective protection of the target organism's substrate. In fig. 1 of the attached drawings, points A and B are the toxic index values for the biocidal compounds Y and X, • respectively, and the straight line between two points represents the toxic index values that would be obtained if

the biocidal effects of compounds X and Y were merely additive. If for any particular relationship of X: Y, the value of the toxic index is determined to be less than the value of the straight line (for example at point C) then compounds X and Y are synergistic for that particular relationship.

A convenient method of signaling the synergistic properties of a formulation is to use a synergy index. This can be defined as:

-,. ,. . , theoretical toxic index synergism index (SI) = --------------------- actual toxic index theoretical toxic index can be calculated by interpolating the theoretical line of action. An SI value of 1 indicates that there is no synergism. As the SI value increases, so does the degree of synergism.

A) COMPOSITIONS CONTAINING TEBUCONAZOLE (I) Fungicidal effect on basidiomycetes

The fungicidal activity was measured according to the prEN113 test method. This method involves the treatment of small wooden blocks with the preserving compound and their subsequent exposure to rot fungi in a small test vessel. Using a range of treatment concentrations, behavioral estimation is performed after 12 weeks of an exposure period by measuring the weight loss of the blocks. The average values for weight loss for duplicate samples allow the determination of an estimated concentration, or load of preservative in the wood, that will be effective against the target fungus. In order to demonstrate synergism the results were obtained using tebuconazole alone, a substituted cuproammonium compound, and then both in a mixture, the constituents of which are given as example 1. The copper to tebuconazole ratio for this example was 25: 1. All tests were performed after washing with cold water,

according to the method published as EN84. Although boron was included in these formulations, this washing process is sufficient to remove all boron. There is therefore no contribution of this active ingredient to the overall effectiveness of the tests. The results are given in Tables 1 and 2 for the individual active ingredients, and in Table 3 for the mixture.

Table 1 - toxic limit values for tebuconazole determined by the EN113 method (kgm ^-3 of active ingredient).

Toxic limit toxic index Kgm ^-3 Kgm ^-3 P. placenta 0.3 - 0.5 0.4 C. Versicolor 0.2 - 0.4 0.3 C. puteana 0.05 - 0.2 0.125 Tables 2 - Toxic limit values for compounds substituted cuproammonium determined by EN113 method (Kgm ^-3 of copper) Toxic limit toxic index Kgm ^-3 Kgm ^-3 P. placenta > 4.62 estimated value 5.0 C. trabeum > 4.49  5.0 C. puteana 3.1 - 5.4 4.25

These results clearly indicate the differential behavior between tebuconazole and cuproammonium compounds. For the most aggressive fungus • - Q (Poria placenta) about 0.4 kgm of tebuconazole is necessary for effectiveness, while 16

rivers approximately 5.0 kgm ^-3 of copper to prevent rot.

Further results of the tests using a 25: 1 copper mixture for tebuconazole are shown in Table 3. Poria placenta was used since this is the most aggressive fungus in the complete EN113 test for these two compounds.

Table 3 - toxic limit values for a 25: 1 copper: tebuconazole mixture determined by the EN113 method (toxic limit values given _ as Kgm Cu)

Toxic limit toxic index Kgm ” ³ Cu Kgm ” ³ Cu P. placenta 1.4 - 2.2 1.8

These results were represented in a schematic graph, in fig. 2 of the attached drawings.

In fig. 2 the dotted line illustrates the expected concentration of the cuproammonium and tebuconazole compound that would be required in a composition containing copper and tebuconazole in a 25: 1 weight ratio if the behavior of copper and tebuconazole were merely additive (3.2 kgm ^-3 copper and 0.13 kgm ” ³ of tebuconazole). The solid line illustrates the actual concentration determined to be necessary. These concentrations are considerably lower than expected (1.8 kgm ^-3 copper and 0.072 kgm ^-3 tebuconazole), producing a synergism index of 1.78.

II) Fungicidal effect of several copper: tebuconazole ratios

Previous tests have been expanded to determine the relationship ranges in which there is synergism between cuproammonium and tebuco compounds17

nazole. A simplified version of the prEN113 trial was used: the trial duration was 6 weeks; the target fungus was C. puteana, since the growth rate of this copper-tolerant fungus is compatible with a 6-week exposure test. All blocks were washed with cold water according to the prEN84 method. The tested compositions were obtained by mixing the packages A and B described in example 6 to obtain the copper: tebuconazole ratios indicated in table 4, which also shows the toxic and synergism indices determined for these ratios.

Table 4

Formulation Toxic index toxic index index of (kgm ³ 1 theoretical (Kcrm 1 synergy Tebuconazole 0.048 there Cuprammonium Compound 4.91 Ass 1:10 0.048 there 0.048 there 1.00 25: 1 <0.48 Ass 0.95 Ass > 2.08 500: 1 <1.90 Ass 4.10 Ass > 2.10 1000: 1 4.34 Ass 4.40 Ass 1.01

N.B.Relations are given as copper: tebuconazole ai - means active ingredient.

These values clearly show the surprising differences in fungicidal activity exhibited by different Cu ratios: tebuconazole; these are shown schematically in fig. 3. While for 1:10 and 1000: 1 the fungicidal activity of copper and tebuconazole are purely additive, for 25:: 1 and 500: 1 the formulations are significantly synergistic.

ί 1

III) Fungicidal effect against putrefaction

The mixture used in the previous tests was also tested in a barn fungi test, in which the activity against putrefaction was verified. The results of this test are particularly important for determining the suitability of wood preservatives for use in contact with the soil.

Small pieces (15 x 3 x 100 mm) of beech wood were exposed to unsterilized soil, nine tenths of its length. The exposure period was 6 months. Washed samples were used. Length loss was used as the main criterion for the evaluation. 80% of the residual length was used as the level at which the toxic limits were determined.

The toxic thresholds in beech against putrefaction for the individual components and mixtures after washing are given below (in this table the toxic limit and the toxic index for the cuproammonium compound are given in Kg of copper per m ³ ).

Table 5

Toxic limit toxic index (kgm ^-3 active ingredient) (kgm ^-3 active ingredient) Tebuconazole > 9.09 > 9.09 Cuprammonium Compound > 8.44 > 8.44 Copper: Tebuconazole 25: 1 1.65 - 3.25 2.45

The interaction between copper and tebuconazole for behavior in beech wood

putrefaction is shown in fig. 4 of the attached drawings.

In fig. 4 the dotted line illustrates the expected concentrations of copper and tebuconazole required in a composition containing copper and tebuconazole in a 25: 1 weight ratio if the behavior of copper and tebuconazole were merely additive (> 8.44 kgm ^-3 copper and> 0 , 33 kgm ^-3 tebuconazole). The solid line illustrates the actual concentrations determined as necessary. These concentrations are considerably lower than expected (2.44 kgm of copper and 0.01 kgm of tebuconazole).

These results show that the copper: tebuconazole synergism index combined in a 25: 1 ratio is> 3.58 when tested against putrefaction fungi.

B) COMPOSITIONS CONTAINING OR PROPICONAZOLE, OR AZACONAZOLE

Tests were carried out to evaluate the efficacy against basidiomycetes with propiconazole and azaconazole, alone and in their mixtures with copper, using relationships within the scope of the invention. The tests were performed according to both the EN113 method and the published method as IRG / WP / 2329, and the toxic limits were identified as described above for the fungus Coniophora puteana.

The toxic limits are indicated in the table below (in this table the toxic limit and the toxic index for the cuproammonium compound are indicated in Kg of copper per m ³ ):

Table 6

Active ingredient Toxic limit _ o (Kgm ^J total active ingredient) toxic index (Kgm ” ³ total active ingredient) Cuprammonium Compound 3.1 - 5.4 4.25 Propiconazole 0.3 - 0.7 0.5 Azaconazole 0.7 - 1.3 1.0 Cu: Propiconazole 5: 1 <0.504 <0.504 Ass: Azaconazole 5: 1 1.008 - 2.04 1.52

The interaction between propiconazole and copper is illustrated in fig. 5 and the interaction for azaconazole and copper is illustrated in fig. 6.

In fig. 5 the dotted line shows the expected concentrations of copper and propiconazole in a composition containing copper in a 5: 1 weight ratio if the behavior of copper and tebuconazole were merely additive (1.6 kgm ^J of copper and 0.3 kgm ^J of propiconazole ). The solid line shows the actual concentrations determined as necessary. These concentrations are considerably lower than expected (<0.42 kgm ' ³ of copper and <0.084 kgm' ³ of propiconazole). A synergism index of> 3.77 was calculated from these results for Cu: propiconazole combined in a 5: 1 ratio.

In fig. 6th dotted line shows the expected concentrations of copper and azaconazole needed in a composition containing copper in a 5: 1 weight ratio if the behavior of copper and azaconazole were merely additive (2.5 kgm ' ³ of copper and

0.5 kgm ^-3 of azaconazole). The solid line shows the actual concentrations determined as necessary. These concentrations are considerably lower than expected (1.26 kgm ^-3 copper and 0.25 kgm ^-3 azaconazole).

These results suggest that copper: azaconazole mixtures combined in a 5: 1 ratio are synergistic with a synergism index of 1.97.

Claims (2)

Compositions for the conservation of wood and cellulosic materials characterized by comprising a biocidal metallic compound and a fungicidal compound containing a triazole group, in which the weight ratio of metal atom: fungicidal compound containing the triazole group is at least 1: 2.5 ; with the particular exceptions of (I) a composition (a) containing 1.320% by weight of sodium nitrite 1.190% by weight of copper sulfate 5H ₂ 0, 0.400% by weight of boric acid 0.625% by weight of sodium heptonate , 0.390% by weight of sodium hydroxide, 0.012% by weight of tebuconazole, 0.391% by weight of a surfactant mixture in xylene, and 95.762% by weight of water, and (II) the composition (b) containing 0.00025 % by weight of a compound of formula: 0.025% by weight of a compound of formula CHq - CH - NH - CS - S \ Zn / CH ₂ - NH - CS - S 2.525% by weight of dimethylformamide, 0.006313% by weight of an alkyl-aryl-polyglycolic ether, the rest of the composition being water. _ ₂ A composition according to claim 1 , characterized in that the metal compound is a compound of a metal selected from: copper, aluminum, manganese, iron, cobalt, nickel, zinc, silver, cadmium, tin, antimony, mercury, lead and bismuth. _ ₃ to _ Composition according to claim 1 or 2, characterized in that the compound containing a triazole group is chosen from compounds of formula (A): OH, CH ₂ —CH ₂ —C— R _x 9 ^H 2 (A) [where R] _ represents an alkyl group with 1 to 5 carbon atoms, straight or branched chain and R ₂ represents a phenyl group optionally substituted by one or more substituents chosen from halogen atoms or alkyl or alkoxy groups containing in each case with 1 to 3 carbon atoms, phenyl or nitro groups] and compounds of formula (B): (B) in which R ₃ is defined as R ₂ above, and R ₄ represents a hydrogen atom or an alkyl group having 1 to 5 carbon atoms, straight or branched chain - 4th - Composition according to either of Claims 1 and 2, characterized in that the compound containing a triazole group is chosen from tebuconazole, propiconazole, azaconazole, hexaconazole and diphenaconazole. - 5th - Composition according to any of the preceding claims, characterized in that the weight ratio of metal to triazole compound is between 750: 1 and 1: 1. - 6th - Composition according to Claim 5, characterized in that said ratio is between 500: 1 and 5: 1. Composition according to Claim 6, characterized in that said ratio is about 25: 1. - 8th - Process for the treatment of a wooden substrate or other cellulosic material characterized in that it comprises the application to said substrate of a composition as defined in any of the preceding claims. - 9th - Process for the treatment of a wooden substrate or other cellulosic material characterized in that it comprises the application to said substrate of composition (b), as defined in claim 1. The applicant claims the priority of the English application submitted on 01-08-1991, under number 9116672.8.