US4038445A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Coated paper
Assignee: Wiggins Teape UK PLC
•
Filing: 1975-06-26
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Granted: 1977-07-26
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Expires: 1995-06-26
Abstract
Abstract Microcapsule coated sheet material for use in pressure sensitive copying systems is produced by a method which comprises forming an aqueous coating composition containing microcapsules, particulate stilt material and a biner, foaming the coating composition, applying the foamed composition to a web of sheet material, and metering the composition on the web to a desired coating weight by means of a metering member, for example a blade which preferably is flexible, in contact with the coating composition on the web. The foamed composition is preferably applied to the web by means of a fountain applicator.
Inventors
- 👤 Neil George Douglas Robertson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 17:09
CPC Classifications
B; B41; B41M; B41M5/00; B41M5/124; B41M5/1246
Claims Analysis
Total Claims: 9
Claim 1
Independent Claim
198 words
A method of coating a web of paper with pressure sensitive microcapsules containing a color forming material, for use in pressure sensitive copying systems, which method consists essentially of the following sequential steps: a. forming in a mixing zone an aqueous coating composition containing dispersed therein said microcapsules, particulate stilt material of a size greater than that of the microcapsules and in an amount sufficient to protect said microcapsules against premature rupture, and a binder in an amount sufficient to enhance the adhesion of the microcapsules and the particulate stilt material to the web; b. foaming said composition to impart to it a gas content of at least about 25% and a gas bubble size predominantly in the range of 10 to 100 μm; c. applying said foamed composition to the web at a coating speed of at least about 250 m/min.; d. metering the foamed composition on the web by means of a mechanical metering member which is in contact with the foamed coating composition on the web and smooths it to a uniform desired coatweight; e. returning metered off coating composition to said mixing zone, and f. drying the metered foamed coating composition on the web.
Claim 2
Independent Claim
198 words
A method of coating a web of paper with pressure sensitive microcapsules containing a color forming material, for use in pressure sensitive copying systems, which method consists essentially of the following sequential steps: a. forming in a mixing zone an aqueous coating composition containing dispersed therein said microcapsules, particulate stilt material of a size greater than that of the microcapsules and in an amount sufficient to protect said microcapsules against premature rupture, and a binder in an amount sufficient to enhance the adhesion of the microcapsules and the particulate stilt material to the web; b. foaming said composition to impart to it a gas content of at least about 25% and a gas bubble size predominantly in the range of 10 to 100 μm; c. applying said foamed composition to the web at a coating speed of at least about 250 m/min.; d. metering the foamed composition on the web by means of a mechanical metering member which is in contact with the foamed coating composition on the web and smooths it to a uniform desired coatweight; e. returning metered off coating composition to said mixing zone, and f. drying the metered foamed coating composition on the web.
Claim 3
Dependent Claim
34 words
A method as claimed in claim 1 wherein the metering member is a flexible blade which flexes in the direction of the web movement such that the web runs substantially tangentially to the blade.
Claim 4
Dependent Claim
23 words
A method according to claim 1 wherein a binder and a separate foaming agent are included in the composition prior to foaming it.
Claim 5
Dependent Claim
19 words
A method according to claim 1 wherein said binder itself produces an adequate foam when the composition is foamed.
Claim 6
Dependent Claim
14 words
A method as claimed in claim 1 wherein the metering member is a blade.
Claim 7
Dependent Claim
22 words
A method as claimed in claim 2 wherein the foamed composition is applied to the web by means of a fountain applicator.
Claim 8
Dependent Claim
20 words
A method as claimed in claim 1 wherein the gas content of the foamed composition is from 45 to 70%.
Claim 9
Dependent Claim
14 words
Sheet material which has been coated by a method as claimed in claim 1.
References Cited (Backward Citations)
US3607341A
Cited
US3897578A
Cited
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 |