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US4414261A Expired / Lapsed US ⏱️ 0.0 years remaining

Adhesive tape

Assignee: Mitsubishi Chemical Corp
•
Filing: 1982-09-14
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Granted: 1983-11-08
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Expires: 2002-09-14
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Abstract

Abstract An adhesive tape comprises a base sheet and an adhesive layer coated on one side of the base sheet, characterized in that said base sheet comprises an intermediate layer made of a crystalline polypropylene containing from 25 to 35% by weight of a petroleum resin and outer layers made of a crystalline polypropylene laminated on both sides of the intermediate layer, said intermediate layer having a thickness within a range of from 60 to 90% of the total thickness of the base sheet and the layers of the base sheet being biaxially oriented so that the orientation in the longitudinal direction is greater than the orientation in the transverse direction.

Inventors

  • 👤 Kazuhiko Nanbu

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-28 21:46
CPC Classifications
C; C09; C09J; C09J7/00; C09J7/20; C09J7/29; C09J2301/00; C09J2301/10; C09J2301/16; C09J2301/162; Y; Y10; Y10T; Y10T428/00; Y10T428/24; Y10T428/24942; Y10T428/2495; Y10T428/24959; Y10T428/24967; Y10T428/24975; Y10T428/28; Y10T428/2843; Y10T428/2848; Y10T428/31504; Y10T428/31855; Y10T428/31909; Y10T428/31913; Y10T428/31928

Claims Analysis

Total Claims: 14
Claim 1
Independent Claim 111 words
An adhesive tape which comprises a base sheet and an adhesive layer coated on one side of the base sheet, characterized in that said base sheet comprises an intermediate layer made of a crystalline polypropylene containing from 25 to 35% by weight of a petroleum resin and outer layers made of a crystalline polypropylene laminated on both sides of the intermediate layer, said intermediate layer having a thickness within a range of from 60 to 90% of the total thickness of the base sheet and the layers of the base sheet being biaxially oriented so that the orientation in the longitudinal direction is greater than the orientation in the transverse direction.
Claim 2
Dependent Claim 111 words
An adhesive tape which comprises a base sheet and an adhesive layer coated on one side of the base sheet, characterized in that said base sheet comprises an intermediate layer made of a crystalline polypropylene containing from 25 to 35% by weight of a petroleum resin and outer layers made of a crystalline polypropylene laminated on both sides of the intermediate layer, said intermediate layer having a thickness within a range of from 60 to 90% of the total thickness of the base sheet and the layers of the base sheet being biaxially oriented so that the orientation in the longitudinal direction is greater than the orientation in the transverse direction.
Claim 3
Dependent Claim 44 words
The adhesive tape according to claim 1 wherein the crystalline polypropylene in the intermediate layer and outer layers of the base sheet is an isotactic polypropylene having an isotactic index of from 90 to 97% and a melt index of from 0.5 to 4.0.
Claim 4
Dependent Claim 31 words
The adhesive tape according to claim 1 wherein the petroleum resin is selected from the group consisting of an aliphatic petroleum resin, an alicyclic petroleum resin and an aromatic petroleum resin.
Claim 5
Dependent Claim 18 words
The adhesive tape according to claim 1 wherein the petroleum resin is a fully hydrogenated alicyclic petroleum resin.
Claim 6
Dependent Claim 52 words
The adhesive tape according to claim 1 wherein the ratio of the thickness of the crystalline polypropylene layer laminated on one side of the intermediate layer to the thickness of the crystalline polypropylene layer laminated on the other side of the intermediate layer, is within a range of from 1.5:1 to 1:1.5.
Claim 7
Dependent Claim 31 words
The adhesive tape according to claim 1 wherein the base sheet has a thickness of from 30 to 40μ and the adhesive layer has a thickness of from 15 to 25μ.
Claim 8
Dependent Claim 23 words
The adhesive tape according to claim 1 which is subjected to an electron beam irradiation of about 10 Mrad after the biaxial orientation.
Claim 9
Dependent Claim 19 words
The adhesive tape according to claim 1 wherein the intermediate layer contains a small amount of an ethylene-α-olefin copolymer.
Claim 10
Dependent Claim 19 words
The adhesive tape according to claim 8 wherein the ethylene-α-olefin copolymer is an ethylene-propylene copolymer or an ethylene-butene-1 copolymer.
Claim 11
Dependent Claim 19 words
The adhesive tape according to claim 1 wherein the adhesive layer is made of an acrylic acid ester adhesive.
Claim 12
Dependent Claim 32 words
The adhesive tape according to claim 10 wherein a polypropylene modified with a small amount of a carboxylic acid or its derivative, is provided between the base sheet and the adhesive layer.
Claim 13
Dependent Claim 51 words
The adhesive tape according to claim 1 wherein the layers of the base sheet are biaxialy stretched for orientation with a transverse stretching rate of at least 6 times and the product of the longitudinal and transverse stretching rate being within a range of at least 42 and less than 72.
Claim 14
Dependent Claim 22 words
The adhesive tape according to claim 12 wherein the stretching orientation is conducted at a temperature of from 150° to 160° C.

References Cited (Backward Citations)

US4137362A Cited
US4173676A Cited
US4335171A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1986-11-07 1987-05-09 1987-11-08 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1990-11-07 1991-05-09 1991-11-08 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1994-11-07 1995-05-09 1995-11-08 $7700.00 Window Closed / Lapsed

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