FI91534B - Composition having anti-fouling properties, and its use - Google Patents

Abstract

A substance composition which possesses properties which prevent growth and which is suitable for use as a ship bottom tint, and which substance composition comprises dispersing agents and solvents, and possibly other substance components, such as binding agents, fillers, dyes and pigments, and also a composition in which particulate polytetrafluoroethene, which is known per se, and at least 5% by weight of Cu powder, calculated on the weight of the ready-to-use covering, and Cu compounds, such as growth-preventing substances, are present.

Description

91534

COMPOSITION OF SUBSTANCES WITH ANTI-GROWTH PROPERTIES AND ITS USE - COMPOSITION WITH BEHAVIOR-MULTIPLE EQUIPMENT

The present invention relates to a composition of matter having anti-vegetation properties and suitable for use as a primer or the like in a ship.

With respect to the features of the invention, reference is made to the claims.

The composition of matter of the invention comprises a combination of particulate polytetrafluoroethylene and an anti-growth agent or antifouling agent. Antifoulant means substances which, when combined with a coating, prevent or resist the adhesion of aquatic organisms to the coating or the growth on the coating, such as bacterial or silica sludge, algae, sawdust, mussels, tube worms, seaweeds, moss, teredos, spores, martes -20 mia, oysters, bryozoans, etc. According to the invention, this substance is combined with the coating to the extent that it is sufficient to prevent the adhesion or growth of the organism in aqueous environments such as lakes, waterways and seawater as well as e.g. pipelines and industrial installations, e.g. in heat exchangers,: in cooling towers and the like.

Polytetrafluoroethylene can be present in particulate form, with a particle size of less than e.g. 20 and often less than 10 or 15. Often the majority or 30 parts of the particles have a grain size greater than 0.1 μm or 1 μm. The usual reactor size averages about 5 pm. The density of the polytetrafluoroethylene is preferably 2.14 to 2.20, especially about 2.16. The melting point (crystalline) is suitably about 280 to 330 ° C, in particular 35 to about 300 ° C. The average molecular weight can vary within wide limits, e.g. from 1000 to 20000 or 2000 to

5000, preferably about 3700. Softening point (ASTM

91534 2 E-28-58-T) may vary e.g. from 240 to 280 ° C, e.g. about 265 ° C.

Polytetrafluoroethylene is commercially available as dispersions in a suitable dispersant, e.g. chlorinated or fluorinated hydrocarbons, such as fluorinated hydrocarbons sold under the trade name freon. One example is trichlorotrifluoroethane.

In some cases, it is also preferred that if the solvent or dispersant has a certain solubilizing effect on tetrafluoroethylene, it may dissolve e.g. 25%, or 1 to 15 *, preferably about 10%. Also lower dissolution rates, e.g. 0.1 to 1% may give a certain advantageous effect. This dissolving effect may be partial so that the polymer only swells or forms a kind of colloid.

One of the anti-growth components of the compositions of matter according to the invention is copper metal in powder form or copper oxide, e.g. Cu 2 O. Along with these, substances such as a colloidal silica gel, e.g., one prepared by flame hydrolysis from silicon compounds, can be used.

Thus, the composition according to the invention contains dispersants and solvents as well as possibly other ingredients, such as binders, fillers and pigments, as well as polytetrafluoroethylene and growth inhibitors: * antiseptics; the antitumor component is always copper metal in powder form or copper oxide.

The amount of anti-growth agents can vary within wide limits. Based on the weight of the finished surfaces, the composition may contain from 90 to 95% by weight. up to 50% by weight, and in particular up to 25% by weight. Lower concentrations, e.g. up to 5 or 10% by weight, are also suitable for certain types. The lower effective limit also varies depending on the type of substance and can be e.g. between 5-10% by weight. Lower concentrations of 91534 3, e.g. up to 1% by weight or 0.1% by weight, are also suitable.

The amount of polytetrafluoroethylene varies within wide limits depending on the amount of anti-growth agent 5 and other ingredients, e.g. binder. Based on the weight of the finished coating, the amount of polytetrafluoroethylene can increase up to 90-95% by weight, preferably up to 50% by weight and in many cases up to 25% by weight.

Concentrations up to 5-10% by weight are also useful. The lower concentration limit also varies depending on the other ingredients and the requirements set. A lower limit between 10 and 25% is often desirable, but lower concentrations are also useful, e.g. concentrations up to 5% by weight and up to 1% by weight.

15 In addition to polytetrafluoroethylene and anti-growth agents, the coating composition may also contain, for example, binders and pigments as well as other similar additives. Suitable binders include, for example, epoxy resins and other thermoplastic or curable binders useful in conjunction with polytetrafluoroethylenes. Many such substances are described in the literature, e.g. SE 219 806. Examples which may be mentioned are curable and non-curable plastics, such as phenolic rubbers, urea formaldehyde plastics, alkyd plastics, epoxy plastics, polyurethane plastics, alkyl silicon plastics and silicones.

With the compositions according to the invention it is also possible to coat a surface first provided with a base treatment agent 30 in some form or a primer of a type known per se, e.g. phosphate coating, chromate coating, oxalate coating or En-35 is widely known for such primers or primer compositions.

In addition to the mentioned ingredients, the material compositions according to the invention 91534 4 preferably also contain solvents which are removed after application of the material composition to the surface by evaporation or dissolution. Examples of solvents are halogenated hydrocarbons, such as time and alkene hydrocarbons, e.g. chlorinated and / or fluorinated hydrocarbons, e.g. of the methylene chloride, trichlorethylene and freon type, e.g. hydrocarbons having 1, 2, 3 or 4 carbon atoms in the chain, wherein a substantial portion of the carbon atoms are substituted with fluorine 10 and optionally chlorine, preferably at least half or all of the carbon atoms substituted with fluorine and optionally chlorine, especially trifluorotichloroethylene. Aromatic solvent type hydrocarbons can also be used. Furthermore, solvent mixtures containing said type of solvents, such as trichlorotrifluoroethylene (e.g.

50%) together with one or more toluene, n-heptane and preferably trichloroethane.

The amount of solvent and / or dispersant, based on the total weight, can increase up to 95% by weight, preferably up to 75% by weight or 50% by weight, in certain cases up to 25% by weight, but is preferably at least 10% by weight, in particular at least 20% by weight and in particular at least 40% by weight. Other polar or non-polar liquids, e.g. hydrocarbons, alcohols, ketones having 2 to 8 carbon atoms, as well as water can also be used as a solvent or dispersant for paint compositions, in which case the ingredients of the composition can be dispersed separately in water or mixed into a dispersion or solution. -30 sex in a water-soluble or water-insoluble liquid that is dispersed in water.

·: The thickness of the coating to be formed may vary. Usually a coating thickness of less than 50 μm, preferably less than 25 μm, e.g. less than 10 or less than 5 35 μπι is used. The usual lower limit for layer thickness is 1 to 5 and the preferred layer thickness range is 5 to 15. The amount of the antifouling agent, e.g. copper powder or cuprous oxide, can then increase up to e.g. 50 g / m 2, preferably up to 25 g / m 2, e.g. up to 10 or 15 g / m 2. A suitable lower limit is often between 1 and 5 g / m 2, but lower concentrations, e.g. 0.1 g / m 2, are also useful. A concentration of about 25 to 75% by weight, preferably about 50% by weight of the binder is often suitable, e.g. for copper powder and the like.

An example of a suitable pigment having special properties is pigments forming the layer crystal structure, e.g. molybdenum sulphide, MoS2 or graphite. A suitable concentration of this substance is between 0.1-5 or 10% by weight. MoS2 gives a special effect together with polytetrafluoroethylene and also contributes to a reduction in friction as well as an increase in speed. Graphite can also be used to replace MoS2 or in combination with this.

The compositions of matter according to the invention can be used in various ways, e.g. as one-component compositions of materials, but also as multi-component compositions of materials. One suitable type is a two-component composition comprising a fluid component comprising polytetrafluoroethylene dispersed in a solvent and optionally a binder and a pigment component comprising an anti-growth agent and optionally other additives and optionally a dispersant. The pigment part is preferably solid and powdery and is mixed with the liquid component before use. For example, a flowable component is preferred, containing as major constituents polytetrafluoroethylene 30 e.g. about 20-80% by weight and the remainder flowable dispersants, e.g. of the freon type, as well as about 80% by weight of other solvents, e.g. trichlorethylene or the like (e.g. CHLOROTHENE NUR sold by Dow Chemical). The flowable component may also contain other types of binders, e.g. those mentioned above. The pigment part may contain copper powder e.g. 50-90% by weight and molybdenum disulphide in an amount of 10-50% by weight, 91534 6 e.g. about 70% by weight copper powder and 25% by weight molybdenum disulphide. The weight ratio of the fluid component to the pigment component may be about 25 to 200 g of pigment per 800 to 975 g of fluid component, with a total weight of 1000 g. A suitable amount is about 875 g of a flowable component and about 125 g of pigment together with the above-mentioned assembly of a flowable polytetrafluoroethylene-containing component and a Pigment component.

The usual size of a copper powder is about 30 to 300 mesh, e.g. 50 wt% "fine" and 50 wt% "superfine". Preferably, flake-like particles with a thickness / diameter ratio of 1/10 to 1/100, preferably 1/20 to 1/50 are used, preferably at least 50% by weight and in particular at least 80% by weight of particles having a size such that the diameter is less than 10 μιη.

Coatings can be formed in various ways, e.g. by brush, rollers, spraying, dipping, casting.

The coatings can also be melted on the substrate by heating polytetrafluoroethylene, e.g. above 280 ° C, such as 300-315 ° C, for 1-20 minutes, e.g. 5-10 minutes, or by flame spraying, e.g. plasma spraying.

The compositions according to the invention can be used to coat various surfaces, e.g. steel, zinc, aluminum, stainless steel, plastic, concrete, stone, (silicate) glass, porcelain, artificial stone, brick, wood, primers or il-30. consisting of paints, varnishes, varnishes, phosphates, chromates, etc.

: Compositions may also contain corrosive ingredients such as phosphoric acid and other acidic ingredients that adhere to the substrate and improve adhesion. These ingredients may be of the Wash-primer type and may also contain, for example, zinc chromate or other chromates and polyvinyl butyral and wash-

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91534 7 primer. Other useful ingredients, eg. Water with a dispersing or containing emulgointiai-agent ainekokoomukaissa, are thermoplastic components, polyacrylates including akryylimonomee-five volumes yhteispolymeraatteja with other unsaturated monomers, polyvinyl acetate, polystyrene, vinyl chloride-vinyylideenikloridikopolymeraatti, other vinyl polymers, styreenibutadieenikopolymeraatit, chlorinated rubber, colfonium resin , linear polyesters such as polyethylene terephthalate, polybutylene terephthalate and the like.

Additional examples of pigments and fillers include anti-corrosion additives such as lead, zinc chromate, zinc metal powder, aluminum-15 metal powder, aluminum bronze powder and the like.

Silicones (organosilicon compounds) useful in accordance with the invention may be of the oil or resin type or curable or non-curable, straight or branched. Silicones are described in detail e.g.

20 in W. Noll: "Chemie und Technologie der Silicone", 2nd edition, Verlag Chemie, Weinhein, BRD, 1968, and in "Chemie und Technologie der Kunststof-fe", Band II, Akademische Verlagsgesellschaft Geest & Portig KG, Leipzig , 1963, pp. 789-858. Also suitable silanes, preferably those which can form; silicone polymers or siloxanes (polysiloxanes) may be included in the compositions of the invention.

The mole weight of the organosilicon compounds used Mole-30 can vary within wide limits, e.g. between 20 and 100,000, e.g. 100-10000.

Ί The amount of organosilicon compound (including polymers) can vary from 0 to 5% by weight, preferably from 0.01% by weight, up to 35% by weight, in particular from 0.1% by weight and in particular from 0.3% by weight, based on the weight of the solid. - from 3% to 3% by weight, in particular up to 1% by weight.

The organosilicon compounds can also partially replace polytetrafluoroethylene in the compositions of matter of the invention. The organosilicon compounds used for this purpose may consist of the above-mentioned silanes, silicones, siloxanes and the like, linear or branched polymers.

The antitumor agents are preferably insoluble in water.

Fillers, e.g., particles, may be added to the coating composition or coating to improve the wear resistance or durability of the coating. An organic or inorganic substance may be used, e.g. fused or sintered water-stable substances such as glass, ceramics, metals, etc. The particles may have a regular shape, e.g.

15 a spherical shape, such as glass spheres, or an irregular shape, e.g., a flake shape, a fibrous shape, a shape obtained by crushing, etc. The filler may also contain an anti-growth agent and / or a carbon fluoropolymer added to or attached to the surface of the filler particles 20. The filler may also have a pigmenting effect or may consist of a pigment.

When glass beads or synthetic resin, e.g. of the vinyl type, the acrylic type or the type of elastic, such as rubber, are used, the diameter is about 1 to 100, preferably 5 to 50 or preferably 5 to 30. Balls can be added to the composition to improve the friction properties of the coating in water.

Example 1 A coating having the following composition was prepared: 100 g of polytetrafluoroethylene having an average molecular weight of about 5,000, 100 g of copper powder 30-300 mesh, 30 g of molybdenum sulfide, dispersing 779 g of a mixture of 200 g of trifluoro-35 trichloroethylene and 570 g of trichloroethane, after which the other ingredients were dispersed in this dispersion. This composition of material was applied, film thickness approx

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91534 9 5 - 10 pm to the bottoms of ships made of plastic, aluminum and steel on top of the paint layer and without the paint layer below, giving a good long-term effect against the vegetation in the seawater.

The adhesion of the coating to the substrate can also be improved in ways known per se, e.g. a primer coating, e.g. an epoxy type, whereby the antifouling coating is applied while the primer-10 coating still provides an adhesion effect to the anti-fouling coating. In the experiment, the above-mentioned antifou-Ling agent was applied to a primer coating of amide-cured epoxy hat obtained by mixing EPON 1001 (Shell) and VERSAMID 15 (General Mills) applied to a substrate of iron, aluminum, zinc and plastic (polyester). , resulting in good performance. Further, the adhesion can be improved by adding binders, as described above. To the above composition may be added 20, calculated in said aliquots, 30 and 60 parts of a mixture of EPON 1001 and VERSAMID. This material assembly was also tested on a substrate consisting of iron, aluminum, zinc and plastic (polyester) with good results.

In further experiments, the coating was heated to sinter this on substrates of iron, aluminum and zinc.

The experiments described above were repeated using an additional 10 wt% glass beads with a mean diameter of 30 at 5. 30 pm, calculated from the solids of the material assembly.

The experiments of the example were repeated, replacing half and the whole amount of copper metal with CuO 2 to give satisfactory results.

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Claims (5)

1. Composition with antifouling properties containing antifouling agent, for use as ship bottom paint or the like, which composition contains dispersants and solvents as well as any additional ingredients, such as binder, filler, pigment and layered pigment pigment. Therefore, the composition contains at least 1% by weight of particulate polytetrafluoroethylene and at least 5, preferably at least 10% by weight of copper metal powder, preferably flake-shaped, or copper oxide, preferably Cu 2 O. 2. A composition according to claim 1, characterized in that the composition contains at least 1 and optionally at least 5 or 10% by weight of polytetrafluoroethylene, whose particle size is preferably less than 20 µm. Composition according to claim 1 or 2, characterized in that the composition contains, as dispersant and / or solvent, halogenated hydrocarbons, in particular fluorine and / or chlorine hydrocarbons having 1, 2, 3 or 4 carbon atoms in the chain, preferably with at least half or all of the hydrogen atoms are substituted with fluorine and optionally with chlorine, e.g. Freon hydrocarbons, such as trifluorotrichloroethane, trichloroethane and tricolorene, preferably in an amount of at least 10% by weight. Use as an antifouling coating of a composition according to any one of claims 1 to 3 on a surface intended to be in contact with water, in particular a bite surface. Use according to claim 4, characterized in that the coating is applied with a thickness in the dry state below 50 µm and preferably less than 25 µm.