(19) United States
(12) Patent Application Publication (io) Pub. No.: US 2005/0035334 Al
Korzhenko et al. (43) Pub. Date: Feb. 17,2005
(54) PTC COMPOSITIONS BASED ON PVDF AND THEIR APPLICATIONS FOR SELF-REGULATED HEATING SYSTEMS
(76) Inventors: Alexander Korzhenko, Saint Victor
D'Epine (FR); Henri-jean Caupin,
Versailles (FR); Romain Fauque,
Harquency (FR); Anthony Bonnet,
Beaumont Le Roger (FR)
Thomas F. Roland, Esq.
Atoflna Chemicals, Inc.
2000 Market St.
Philadelphia, PA 19103 (US)
(21) Appl. No.: 10/902,545
(22) Filed: Jul. 29, 2004
Related U.S. Application Data
(60) Provisional application No. 60/523,473, filed on Nov. 19, 2003.
(30) Foreign Application Priority Data
Aug. 1, 2003 (FR) 03.09551
Oct. 6, 2003 (FR) 03.11680
(51) Int. CI.7 1101B 1 00
(52) U.S. C I 252/500
The present invention relates to a PTC composition comprising, by weight, the total being 100%:
A) 40 to 80% ol PVDF;
B) 0 to 40% (advantageously 10 to 40%) ol an acrylic or styrene polymer;
C) 0 to 40% ol an epoxy resin;
D) 0 to 60% ol at least one metal oxide;
E) 0 to 25% ol a carbonaceous conductive filler D+E being equal to at least 10%.
To prepare the composition ol the invention, the various constituents are blended in such a way that (A) is in the melt state, then the product obtained is extruded, moulded or injection-moulded or else deposited on a substrate. Once the composition has been converted into an article, for example into a sheet or bar, it is provided with at least two electrodes that serve as the power lead-in and return, respectively. The composition may also be placed between two conducting plates that serve as the power lead-in and return, respectively.