Claims Analysis
Total Claims: 10
Claim 1
Independent Claim
107 words
A polymeric insulating material having a high dielectric breakdown voltage, comprising polypropylene which has been obtained in a yield of at least 300,000 g/g-Ti based on titanium in a catalyst upon polymerization, contains ash in an amount not greater than 40 ppm by weight when analyzed by completely burning the polypropylene in air, said ash containing titanium in an amount not greater than 1 ppm by weight based on the weight of the polypropylene, and also contains chlorine in an amount not greater than 2 ppm by weight and boiling n-heptane soluble matter in an amount not smaller than 1 wt.% but not greater than 10 wt.%.
Claim 2
Dependent Claim
55 words
A polymeric insulating material of claim 1, wherein the material comprises high-purity polypropylene containing, per cubic centimeter, not more than 6,000 foreign particles of from 1 µm to 10 µm, both inclusive, not more than 1,000 foreign particles of from 5 µm to 10 µm, both inclusive, and no foreign particles greater than 10 µm.
Claim 3
Dependent Claim
39 words
A polymeric insulating material of claim 1, wherein the polypropylene includes at least one additive selected from an inorganic oxide, an inorganic hydroxide, an organopolysilane, a maleic-anhydride-grafted polypropylene and a silane compound containing at least one organic polyether group.
Claim 4
Dependent Claim
76 words
A polymeric insulating material of claim 3, wherein the inorganic oxide or hydroxide is added as the additive in an amount not smaller than 1 ppm by weight but not greater than 10% by weight, and for example the inorganic oxide or hydroxide is the oxide or hydroxide of magnesium, aluminum or iron, which is free of particles of 10 µm and greater in diameter and has an average particle size not greater than 1 µm.
Claim 5
Dependent Claim
48 words
A polymeric insulating material of claim 3, wherein the additive is present in an amount not smaller than 50 ppm by weight but not greater than 10% by weight, and is the organopolysilane or the maleicanhydride-grafted polypropylene, or the silane compound containing at least one organic polyether group.
Claim 6
Dependent Claim
68 words
A polymeric insulating material of claim 1, wherein the polypropylene has been obtained by polymerizing propylene in the presence of a polymerization catalyst which comprises a solid titanium catalyst component containing titanium, magnesium, a halogen and an electron-donating compound (an internal electron-donating compound), an organometal compound containing a metal selected from Groups 1, 2 and 3 of the Periodic Table and another electron-donating compound (an external electron-donating compound).
Claim 7
Dependent Claim
33 words
A polymeric insulating material of claim 6, wherein the propylene has been subjected to dehalogenation treatment, for example has first been subjected to washing with an inert hydrocarbon, and then to dehalogenation treatment.
Claim 8
Dependent Claim
32 words
A formed polypropylene article having high electrical insulating property, said article having been obtained by stretching the polymeric insulating material of any of claims 1 to 5 in at least one direction.
Claim 9
Dependent Claim
20 words
An electrical insulating film obtained by biaxially stretching the polymeric insulating material of any one of claims 1 to 7.
Claim 10
Dependent Claim
28 words
An electrical insulating film having a thickness of 1 to 6 µm obtained by biaxially stretching the polymeric insulating material of any one of claims 1 to 7.