US4037352A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Electrical device which emits insecticidal vapors
Assignee: Reckitt and Colman North America Inc
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Filing: 1976-09-23
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Granted: 1977-07-26
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Expires: 1996-09-23
Abstract
Abstract A device intended to emit vapors emitted by an active substance, in particular an insecticidal substance, which comprises, in a rigid assembly A. a reservoir intended to contain the active substance and having an evaporation surface for the emission of the active vapors, B. an electrical resistance associated with the said reservoir in such a way as to heat at least the part of the said reservoir which comprises, or is close to, the said evaporation surface, and C. a system for connecting the resistance to a source of electric current: the said reservoir comprises I. a system of two plates of a porous or fibrous material, one of the large faces of one of the plates facing one of the large faces of the other, and a frame for the plates, which separates the space between the two plates from the exterior while leaving entirely or partially free at least one of the two large external faces of the two plates, which can thus serve as an evaporation surface, and Ii. a pyrethrinoid insecticidal substance having a vapor pressure, at 25° C, of between 1 × 10 - 6 and 1.5 × 10 - 4 mbar, with which the two plates are impregnated, The total evaporation surface of the two plates being at least 20 cm 2 , the amount of active substance being sufficient to give efficient evaporation, at 90° C for a period of at least 10 hours, and the thickness of the plates being sufficient to absorb the said amount of active substance: The said resistance is enclosed within the said system and is so constructed as to heat the large internal faces of the two plates to a temperature not exceeding 90° C.
Inventors
- 👤 Claude Hennart
- 👤 Rene Blanc
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 22:49
CPC Classifications
A; A01; A01M; A01M1/00; A01M1/20; A01M1/2022; A01M1/2061; A01M1/2077; Y; Y10; Y10S; Y10S428/00; Y10S428/905
Claims Analysis
Total Claims: 18
Claim 1
Independent Claim
291 words
A device destined for the emission of vapours of an active substance, in particular an insecticidal substance, which comprises, in a rigid assembly, a. a reservoir containing the active substance and having an evaporation surface for the emission of the active vapours, said reservoir comprising i. a system of two plates of a porous fibrous material, one of the large faces of one of the plates facing one of the large faces of the other, and a frame for the plates, which separates the space between the two plates from the exterior whilst leaving entirely or partially free at least one of the two large external faces of the two plates, which can thus serve as an evaporation surface, and ii. an insecticidal pyrethrinoid substance having a vapour pressure, at 25° C., of between 1 × 10 - 6 and 2 × 10 - 4 mbar, said two plates being impregnated, with said substance or substances, the total evaporation surface of the two plates being at least 10 cm 2 , the amount of active substance in said reservoir being sufficient to give effective evaporation, at 90° C. for a period of at least 10 hours, and the thickness of the plates being sufficient to absorb the said amount of active substance, b. an electrical resistance associated with the said reservoir in such a way as to heat at least the part of the said reservoir which comprises, or is close to, the said evaporation surface, said resistance being enclosed within the said system and being so constructed as to heat the large internal faces of the two plates to a temperature of up to 90° C., and c. a system for connecting the resistance to a source of electric current.
Claim 2
Independent Claim
291 words
A device destined for the emission of vapours of an active substance, in particular an insecticidal substance, which comprises, in a rigid assembly, a. a reservoir containing the active substance and having an evaporation surface for the emission of the active vapours, said reservoir comprising i. a system of two plates of a porous fibrous material, one of the large faces of one of the plates facing one of the large faces of the other, and a frame for the plates, which separates the space between the two plates from the exterior whilst leaving entirely or partially free at least one of the two large external faces of the two plates, which can thus serve as an evaporation surface, and ii. an insecticidal pyrethrinoid substance having a vapour pressure, at 25° C., of between 1 × 10 - 6 and 2 × 10 - 4 mbar, said two plates being impregnated, with said substance or substances, the total evaporation surface of the two plates being at least 10 cm 2 , the amount of active substance in said reservoir being sufficient to give effective evaporation, at 90° C. for a period of at least 10 hours, and the thickness of the plates being sufficient to absorb the said amount of active substance, b. an electrical resistance associated with the said reservoir in such a way as to heat at least the part of the said reservoir which comprises, or is close to, the said evaporation surface, said resistance being enclosed within the said system and being so constructed as to heat the large internal faces of the two plates to a temperature of up to 90° C., and c. a system for connecting the resistance to a source of electric current.
Claim 3
Dependent Claim
24 words
A device as described in claim 1, wherein the two plates are placed in parallel, and flat, on either side of the electrical resistance.
Claim 4
Dependent Claim
25 words
A device as described in claim 1, wherein the resistance consists of a resistance wire wound around a plate of a solid electrical insulating material.
Claim 5
Dependent Claim
40 words
A device as decribed in claim 1, wherein the electrical resistance is of a size substantially equal to that of the plates constituting the reservoir, and is separated from the plates constituting the reservoir by a means of electrical insulation.
Claim 6
Dependent Claim
33 words
A device as described in claim 4, wherein the electrical insulation is a coating chosen from amongst lacquers, paints and varnishes which are non-conductors of electricity and are inert towards the active material.
Claim 7
Dependent Claim
37 words
A device as described in claim 4, wherein the electrical insulation consists of two plates of solid electrical insulating material placed either side of the resistance, and is of a material selected from mica, asbestos and polytetrafluoroethylene.
Claim 8
Dependent Claim
59 words
A device as described in claim 1, wherein the plates which constitute the reservoir are made from at least one of the following materials: non-sized cellulose boards, boards containing asbestos, glass fibre boards, polymeric fibre boards, wool, a mixture of wool and cotton, felts, baked clay tiles, sintered alumina and porcelains which have not been subjected to biscuit baking.
Claim 9
Dependent Claim
41 words
A device as described in claim 1, wherein said frame is in the form of a case which surrounds the two plates constituting the reservoir and of which the faces superposed over the external faces of the two faces are perforated.
Claim 10
Dependent Claim
21 words
A device as described in claim 1, wherein the said frame is made of solid polyethylene, solid polypropylene or solid polyamide.
Claim 11
Dependent Claim
21 words
A device as described in claim 1, wherein the volume of the reservoir is between 4 and 400 cm 3 .
Claim 12
Dependent Claim
26 words
A device as described in claim 10, wherein the surface of one of the sides of a plate is between 20 and 400 cm 2 .
Claim 13
Dependent Claim
41 words
A device as described in claim 11, wherein the evaporation surface area of one of the large faces of a plate is between 40 and 200 cm 2 , and the thickness of a plate is between 0.2 and 6 millimeters.
Claim 14
Dependent Claim
35 words
A device as described in claim 12, wherein the resistance is such as to absorb a power of between 0.5 and 10 watts per square decimeter of external surface of the plates constituting the reservoir.
Claim 15
Dependent Claim
51 words
A device as described in claim 10, wherein the plates of the reservoir are impregnated with 0.2 to 2 times their weight of a composition which contains at least 5%, calculated relative to the weight of the said composition, of an insecticidal substance having a vapour pressure in the defined range.
Claim 16
Dependent Claim
33 words
A device as described in claim 14, wherein the said composition contains an adjuvant which is inert towards the pyrethrinoid insecticidal compounds and is chosen from amongst diluents, thickeners, stabilisers, perfumes and dyestuffs.
Claim 17
Dependent Claim
20 words
A device as described in claim 14, wherein the said composition has a melting point not exceeding about 120° C.
Claim 18
Dependent Claim
33 words
A device as described in claim 14, wherein the weight of the said composition contained in the reservoir is between 0.5 and 1.5 times the weight of the plates of the said reservoir.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1980-07-25 | 1981-01-24 | 1981-07-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1984-07-25 | 1985-01-24 | 1985-07-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1988-07-25 | 1989-01-24 | 1989-07-26 | $7700.00 | Window Closed / Lapsed |