US2708640A - Toxic coating composition and method of applying said composition to wood - Google Patents

Description

United States Patent TOXIC COATING COMPOSITION AND METHOD OF APPLYING SAID COMPOSITION TO WOOD Wayne K. Davis, Oakland, Calif.

No Drawing. Application September 4, 1951, Serial No. 245,085

4 Claims. (Cl. 117-149) .My invention relates to the protection of wood and wood structures against wood-destroying organisms such as termites and fungus, and more particularly to material .and method of protecting wood and wood structures against such infestation.

Many methods have been attempted or devised to employ chemicals having insecticidal or fungicidal qualities, in the treatment of wood, by applying them to Wood or wood structures at various stages of manufacture or use. Pressure treating in retorts, dipping, spraying and painting are the most common methods of application. Of the aforementioned methods, the first two, namely that of pressure treating in retorts and dipping, can satisfactorily be employed only where the wood or wood structure is not to be altered subsequent to such treatment. However, when such wood or lumber is to be nailed, sawed or otherwise mutilated, as is the case when such wood is to be employed in the fabrication of a structure such as a home, the untreated interior portions of the wood then become exposed, and the protective effect of the treatment is to a substantial degree, nullified. Also, the subsequent effect of seasoning, serves to open cracks into the untreated interior portions of the wood, thus providing access to wood-destroying organisms.

As for the procedure of treating wood by painting or spraying, such treatment is much less effective than pres sure treating in retorts or dipping, unless the procedure of painting or spraying is repeated many times.

Among the objects of the present invention are:

(1) To provide a novel and improved method for treatment of Wood and particularly structural members of a completed structure;

(2) To provide a novel and improved method of treating wood structural members, which will completely cover unexposed surfaces within joints, seams, nail holes, etc.;

(3) To provide a novel and improved method of treating wood structural members, which is simple but extremely eificient;

(4) To provide a novel and improved method of treating wood, which will produce deep penetration of protective material into the wood;

(5) To provide a novel and improved method of treating wood structural members, which method requires but a single visit on the part of the workman;

(6) To provide a novel and improved method for the teratment of structural members of wood, which method can be performed by unskilled labor;

(7) To provide a novel and improved material for treatment of wood;

(8) To provide a novel and improved material for treatment of wood, such material being in heavy paste form suflicient to be self sustaining and resist flow, when applied in layer thicknesses of an inch or so to vertical surfaces;

(9) To provide a novel and improved material for teratment of wood, which will penetrate deeply and displace moisture from wood in the process of penetration;

2,708,640 Patented May 17 1955 (10) To provide a novel and improved material for teratment of wood which will, of its own accord, penetrate joints, crevices, cracks, nail holes, etc., and impregnate the unexposed surfaces thereof;

(11) To provide a novel and improved material for treatment of Wood which when applied to a wood surface will reelase toxic material for an extended period of time;

(12) To provide a novel and improved material in paste form for treatment of wood, which material will extend its protective effect to an area substantially greater than the area of application;

(13) To provide a novel and improved material for treatment of wood, which eliminates the need for containers, wicks, or the like.

Additional objects of my invention will be brought out in the following description of the same.

The method of the present invention involves the preparation of a thick adhesive paste material incorporating therein, in releasable form, chemicalswhich' fu'nction'as fungicides and insecticides. Preferably, the material 'involved, is in the form of an emulsion of the oil-in-water type, in which the fungicidal and insecticidal chemicals are primarily carriedin solution in the oil phase. The emulsion is prepared to a sufficiently thick pasty consistency, as to be self-sustaining, even when applied to a vertical surface in a layer of the order of one-half to one inch thick.

One example of a formula for the preparation of an emulsion of this character is as follows:

Water, 2 /2 gallons Triethanolamine, 3 pints The water and triethanolamine are mixed to constitute the water phase, and following agitation thereof to ob tain a thorough mixture, the remaining ingredients constituting the oil phase, are gradually added with continued agitation until the desired consistency is attained.

A similarly usable emulsion may be prepared by mixing 2% gallons of water and 45 cubic centimeters of ammonium hydroxide with casein in the amount of 8 ounces, to constitute the water phase, and while agitating the same, adding 5% solution of pentachlorophenol in stove oil to the extent of approximately 27 gallons, to obtain the desired consistency.

In each of the foregoing preparations, the principal chemical involved is pentachlorophenol, which is effective both as a fungicide and as an insecticide. However, other toxic materials can be added or substituted in the preparation of the emulsion, to provide a wider range of eifectiveness. Likewise, the proportions of the ingredients are not critical, but may be varied to obtain special results.

In utilizing the foregoing material for its intended purpose, the emulsion is applied as a heavy covering up to an inch or so in thickness, to the wood to be protected, and in a general way, to the area to be treated. The oil phase in the emulsion has the faculty of spreading and gradually penetrating the wood structure to a substantial depth over a period of time, during which, a film forms over the material which inhibits rapid evaporation of the material into the atmosphere and minimizes attendant odor. The gradual breakdown of the emulsion affords the material considerable time, of the order of two or three weeks, in which to become absorbed into the wood structure.

The toxic ingredient being dissolved principally in the oil phase of the emulsion, will thereby be carried over an extended surface area and deep into the wood structure. By reason of such characteristics of the material involved, the material will penetrate the adjacent joints, cracks, nail holes and the like, which would otherwise be inaccessible, and impregnate the unexposed surfaces thereof with the toxic ingredients. Inasmuch as termites, for example, seek such secluded places for their activities, the self-spreading and penetrating characteristics of the material constitute an important factor of the present invention.

It will be apparent, also, in the practice of the above described method, that no special tools or equipment are necessary, in that the material may be smeared on with a spatula or any conveniently handy thin flat piece of wood. Thus no containers or wicks need be employed, and this eliminates the necessity of a return trip on the part of a workman to retrieve such items which in the aggregate would represent an investment that could not be ignored.

It will be apparent that the invention as described above, fulfills all the objects attributable thereto, and

while I have described the same in its preferred form, the

invention is subject to some alteration or modification without departing from the underlying principles involved therein, and I accordingly do not desire to be limited in my protection to such details as I have described, except as may be necessitated by the appended claims.

I claim:

l. The method of treating wood structure as a protection against termites, fungus and the like, which comprises applying to at least a portion of the porous surfaces of the wood, a semi-stable, highly viscous, self-sustaining oil-in-water emulsion, consisting essentially of an oil soluble fungicide and insecticide, a major amount of oil, a minor amount of water, and an emulsifying agent, in a coating of the order of one-half inch thickness, whereby the emulsion will slowly break down and the fungicide l and insecticide in oil solution will be absorbed in the wood over a period of days.

2. The method of treating wood structure as a protection against termites, fungus and the like, which comprises applying to at least a portion of the porous surfaces the order of one-half inch thickness and allowed to break down over a period of days whereby the oil and oil soluble constituents are absorbed by the wood, the emulsion consisting essentially of hydrocarbon oil, present in major quantity, oil soluble fungicide and insecticide, water, and emulsifier, said emulsion being of the oil-in-water type and highly viscous, non free-flowing and self-sustaining.

4. An emulsion ready for use in treating porous wood surface wherein a viscous non-flowing self-sustaining emulsion is applied to the surface of the wood in a coating of the order of one-half inch thickness, and allowed to break down over a period of days whereby the oil and oil soluble constituents are absorbed by the wood,

the emulsion consisting essentially of hydrocarbon oil, present in major quantity, pentachlorophenol, water, and emulsifier, said emulsion being of the oil-in-water type and highly viscous, non free-flowing and self-sustaining.

UNITED STATES PATENTS 1,565,503 Henderson Dec. 15, 1925 1,809,016 Brogden June 9, 1931 2,012,975 Schmittutz Sept. 3, 1935 2,034,152 Parrish Mar. 17, 1936 2,182,081 Hatfield Dec. 5 ,1939 2,206,520 Tisdale July 2, 1940 2,209,970 Hay Aug. 6, 1940 2,296,401 Perkins Sept. 22, 1942 2,447,475 Kaberg Aug. 17, 1948

Claims (1)

1. THE METHOD OF TREATING WOOL STRUCTURE AS A PROTECTION AGAINST TERMITES, FUNGUS AND THE LIKE, WHICH COMPRISES APPLYING TO AT LEAST A PORTION OF THE POROUS SURFACES OF THE WOOD, A SEMI-STABLE, HIGHLY VISCOUS, SELF-SUSTAINING OIL-IN-WATER EMUSLION, CONSISTING ESSENTIALLY OF AN OIL SOLUBLE FUNGICIDE AND INSECTICIDE, A MAJOR AMOUNT OF OIL, A MINOR AMOUNT OF WATER, AND AN EMULSIFYING AGENT, IN A COATING OF THE ORDER OF ONE-HALF INCH THICKNESS, WHEREBY THE EMULSION WILL SLOWLY BREAK DOWN AND THE FUNGICIDE AND INSECTICIDE IN OIL SOLUTION WILL BE ABSORBED IN THE WOOD OVER A PERIOD OF DAYS.