US4303720A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Dielectric product
Assignee: Ludlow Corp
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Filing: 1980-07-10
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Granted: 1981-12-01
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Expires: 2000-07-10
Abstract
Abstract An improved dielectric printing paper and process for making the same, characterized by excellent resolution, contrast, and feel. The paper incorporates an inorganic salt such as magnesium chloride as a conductivity-providing ingredient. The dielectric coating is formed with a high loading of inorganic fillers and is applied by a dry process to form a discontinuous dielectric coating on the conductive paper substrate.
Inventors
- 👤 Philip J. Clough
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-03 19:58
CPC Classifications
G; G03; G03G; G03G5/00; G03G5/10; G03G5/101; G03G5/02; G03G5/0202; G03G5/0205; G03G5/0208; G03G5/0217; Y; Y10; Y10T; Y10T428/00; Y10T428/24; Y10T428/24802; Y10T428/24934; Y10T428/24942; Y10T428/25; Y10T428/256; Y10T428/27; Y10T428/273; Y10T428/31504; Y10T428/31855; Y10T428/3188; Y10T428/31895; Y10T428/31899; Y10T428/31902; Y10T428/31906; Y10T428/31971; Y10T428/31993
Claims Analysis
Total Claims: 22
Claim 1
Independent Claim
116 words
A dielectric paper sheet of the type useful in dielectric printing processes, said paper sheet comprising a cellulosic paper substrate with an inorganic salt distributed therein in a quantity effective to form means to impart conductivity to said sheet when said sheet is equilibrated at 25° C. at relative humidities from 20 to 70%, the improvement wherein said substrate comprises a discontinuous dielectric printing coating on the surface thereon, said coating being formed of an organic polymer and filled with at least 40% inorganic fillers and having a minimum resistivity four orders of magnitude greater than the resistivity of said substrate, and wherein the said fillers are preferentially concentrated at the outer surface of said coating.
Claim 2
Dependent Claim
116 words
A dielectric paper sheet of the type useful in dielectric printing processes, said paper sheet comprising a cellulosic paper substrate with an inorganic salt distributed therein in a quantity effective to form means to impart conductivity to said sheet when said sheet is equilibrated at 25° C. at relative humidities from 20 to 70%, the improvement wherein said substrate comprises a discontinuous dielectric printing coating on the surface thereon, said coating being formed of an organic polymer and filled with at least 40% inorganic fillers and having a minimum resistivity four orders of magnitude greater than the resistivity of said substrate, and wherein the said fillers are preferentially concentrated at the outer surface of said coating.
Claim 3
Dependent Claim
17 words
A dielectric sheet as defined in claim 1 bearing said coating on each side of said substrate.
Claim 4
Dependent Claim
50 words
A sheet as defined in claim 1 wherein said coating is discontinuous, is coated on said paper substrate at from about 5 to 11 lbs. per 3,000 square feet, and has a 100 volt surface resistance of at least about 10 13 ohms at 50% relative humidity and 70° F.
Claim 5
Dependent Claim
14 words
A sheet product as defined in claim 1 wherein said salt is magnesium chloride.
Claim 6
Dependent Claim
50 words
A sheet as defined in claim 2 wherein said coating is discontinuous, is coated on said paper substrate at from about 5 to 11 lbs. per 3,000 square feet, and has a 100 volt surface resistance of at least about 10 13 ohms at 50% relative humidity and 70° F.
Claim 7
Dependent Claim
22 words
A sheet product as defined in claim 1 wherein said printing coating comprises at least about 30% by weight of barium sulfate.
Claim 8
Dependent Claim
15 words
A sheet product as defined in claim 1 wherein said organic polymer is a polyolefin.
Claim 9
Dependent Claim
22 words
A sheet product as defined in claim 2 wherein said inorganic filler comprises at least about 50% by weight of barium sulfate.
Claim 10
Dependent Claim
13 words
A sheet product in claim 5 wherein said organic polymer is a polyolefin.
Claim 11
Dependent Claim
22 words
A sheet product as defined in claim 3 wherein said inorganic filler comprises at least about 50% by weight of barium sulfate.
Claim 12
Dependent Claim
15 words
A sheet product as defined in claim 3 wherein said organic polymer is a polyolefin.
Claim 13
Dependent Claim
15 words
A sheet product as defined in claim 10 wherein said organic polymer is a polyolefin.
Claim 14
Dependent Claim
13 words
A sheet product as defined in claim 1 formed of a ground-wood substrate.
Claim 15
Dependent Claim
13 words
A sheet product as defined in claim 2 formed of a ground-wood substrate.
Claim 16
Dependent Claim
13 words
A sheet product as defined in claim 6 formed of a ground-wood substrate.
Claim 17
Dependent Claim
13 words
A sheet product as defined in claim 7 formed of a ground-wood substrate.
Claim 18
Dependent Claim
13 words
A sheet product as defined in claim 10 formed of a ground-wood substrate.
Claim 19
Dependent Claim
14 words
A sheet of as defined in claim 2 wherein said salt is magnesium chloride.
Claim 20
Dependent Claim
13 words
A sheet as defined in claim 3 wherein said salt is magnesium chloride.
Claim 21
Dependent Claim
23 words
A sheet as defined in claim 1, 2 or 3 wherein said resistivity of said dielectric coating is at least 10 12 ohms.
Claim 22
Dependent Claim
23 words
A sheet as defined in claims 1, 2, 3, 6, 10 or 13, wherein said organic polymer comprises a major portion of polystyrene.
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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) | 1984-11-30 | 1985-06-01 | 1985-12-01 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-11-30 | 1989-06-01 | 1989-12-01 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-11-30 | 1993-06-01 | 1993-12-01 | $7700.00 | Window Closed / Lapsed |