US3884742A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of making plastic book cover
Assignee: Bookwrights Inc
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Filing: 1973-03-21
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Granted: 1975-05-20
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Expires: 1993-03-21
Abstract
Abstract This method for controlling the depth, spacing and uniformity of hinge lines, when making plastic book covers, uses a laminated web or sheet. One component of the laminate is made of plastic material that is heated by exposure to a high frequency electric field and the other component of the laminate is a plastic which undergoes no consequential heating in the high frequency electric field. A tool applies pressure to the first laminate, when the first laminate is heated to a flowable temperature. The tool pressure displaces material of the first laminate down to, or close to, the interface where the laminates are bonded together; but the second laminate has substantially no change in thickness.
Inventors
- 👤 Alvin V Roberts
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 03:55
CPC Classifications
B; B32; B32B; B32B7/00; B32B7/04; B32B7/12; B29; B29C; B29C53/00; B29C53/02; B29C53/04; B29C53/06; B32B27/00; B32B27/06; B32B27/08; B32B27/30; B32B27/306; B32B27/34; B32B27/40; B42; B42C; B42C7/00; B42C7/005; B29C37/00; B29C37/0053; B29C37/0057; B29C59/00; B29C59/02; B29C59/04; B29K; B29K2023/00; B29K2023/10; B29K2023/12; B29K2027/00; B29K2027/06; B29K2027/12; B29K2027/18; B29K2067/00; B29K2075/00; Y; Y10; Y10T; Y10T156/00; Y10T156/10; Y10T156/1052; Y10T156/1082
Claims Analysis
Total Claims: 15
Claim 1
Independent Claim
210 words
THE METHOD OF MAKING A PLASTIC BOOK COVE, WITH METHOD INCLUDES FEEDING INTO A ZONE BETWEEN ELECTRODES A PLASTIC LAMINATE COMPRISING A FIRST COMPONENT LAYER OF PLASTIC, OF ASTIFFNESS SUITABLE FOR FRONT AND BACK PANELS OF A COVER FOR A BOOK AND THAT HAS THE FURTHER CHARACTERISTIC OF BECOMING HIGHLY HEATED AND FLOWABLE LOCALLY BETWEEN SAID ELECTRODES WHEN THE ELECTRODES ARE USED TO PRODUCE A HIGH FREQUENCY DIELECTRIC FIELD AT SAID ZONE, SAID FIRST LAYER BEING BONDED TO A SECOND COMPONENT LAYER OF PLASTIC HAVING SUBSTANTIALLY MORE FLEXIBILITY THAN THE FIRST LAYER AN SUITABLE FOR HINGES OF THE COVER AND HAVING THE FURTHER CHARACTERISTIC THAT SUBSTANTIALLY LESS HEAT ISGENERATED IN IT BY THE SAME HIGH FREQUENCY DIELECTRIC FIELD THATHEATS THE FIRST LAYER, HEATING THE FIRST COMPONENT OF THE LAMINATE,, BETWEEN SAID ELECTRODES BY THE HIGH FREQUENCY DIELECTRIC FIELD, TO A FLOWABLE CONDITION, EXERTING PRESSURE BY ONE OF THE ELECTRODES AGAINST THE FLOWABLE MATERIAL OF THE FIRST COMPONENT WITH SUFFICIENT PRESSURE TO DISPLACE PERMANENTLY THE FLOWABLE MATERIAL TO PRODUCE A GROOVE IN THE FIRST COMPONENT WHILE THE SECOND COMPONENT HAS LESS HEAT GENERATED THERIN BY SAID DIELECTRIC FIELD AND REMAINS BELOW FLOWABLE TEMPERATURE, AND DISPLACING SAID MATERIAL OF THE FIRST COMPONENT ALONG A HINGE OF THE COVER MADE FROM THE LAMINATE.
Claim 2
Independent Claim
210 words
THE METHOD OF MAKING A PLASTIC BOOK COVE, WITH METHOD INCLUDES FEEDING INTO A ZONE BETWEEN ELECTRODES A PLASTIC LAMINATE COMPRISING A FIRST COMPONENT LAYER OF PLASTIC, OF ASTIFFNESS SUITABLE FOR FRONT AND BACK PANELS OF A COVER FOR A BOOK AND THAT HAS THE FURTHER CHARACTERISTIC OF BECOMING HIGHLY HEATED AND FLOWABLE LOCALLY BETWEEN SAID ELECTRODES WHEN THE ELECTRODES ARE USED TO PRODUCE A HIGH FREQUENCY DIELECTRIC FIELD AT SAID ZONE, SAID FIRST LAYER BEING BONDED TO A SECOND COMPONENT LAYER OF PLASTIC HAVING SUBSTANTIALLY MORE FLEXIBILITY THAN THE FIRST LAYER AN SUITABLE FOR HINGES OF THE COVER AND HAVING THE FURTHER CHARACTERISTIC THAT SUBSTANTIALLY LESS HEAT ISGENERATED IN IT BY THE SAME HIGH FREQUENCY DIELECTRIC FIELD THATHEATS THE FIRST LAYER, HEATING THE FIRST COMPONENT OF THE LAMINATE,, BETWEEN SAID ELECTRODES BY THE HIGH FREQUENCY DIELECTRIC FIELD, TO A FLOWABLE CONDITION, EXERTING PRESSURE BY ONE OF THE ELECTRODES AGAINST THE FLOWABLE MATERIAL OF THE FIRST COMPONENT WITH SUFFICIENT PRESSURE TO DISPLACE PERMANENTLY THE FLOWABLE MATERIAL TO PRODUCE A GROOVE IN THE FIRST COMPONENT WHILE THE SECOND COMPONENT HAS LESS HEAT GENERATED THERIN BY SAID DIELECTRIC FIELD AND REMAINS BELOW FLOWABLE TEMPERATURE, AND DISPLACING SAID MATERIAL OF THE FIRST COMPONENT ALONG A HINGE OF THE COVER MADE FROM THE LAMINATE.
Claim 3
Dependent Claim
58 words
The method described in claim 1 characterized by exerting pressure by the electrode against the laminate while the lesser heat generated in the second layer is inconsequential, and supporting the second layer from its surface that is opposite its interface with the first layer during the displacement of the flowable material of the first layer by said electrode.
Claim 4
Dependent Claim
24 words
The method described in claim 1 characterized by making a book cover from a laminate, one of the layers of which is a plastisol.
Claim 5
Dependent Claim
100 words
The method described in claim 1 characterized by using for the first layer a plastic material from the group consisting of polyvinyl chloride; copolymers of vinyl chloride and vinylidene chloride; copolymers of vinyl chloride and vinyl acetate; polyamide (nylon); polyurethanes; homopolymers of polyvinylidene chloride; copolymers of vinylidene chloride and lesser amounts of other unsaturated compounds (Saran); and polyvinyl butyrate, and by using for the second layer a plastic from the group consisting of polypropylene; fluoroplastics; polytetrafluoroethylene (Teflon); copolymers of ethylene and propylene; polyesters such as polyethylene glycol terephthalate (Mylar); ionomer (Surlyn); and spun bonded polyolefins and other non-woven plastic materials.
Claim 6
Dependent Claim
43 words
The method described in claim 1 characterized by making the second layer out of material that is more flexible than the regions of the first layer other than the areas where material is displaced from the first layer to form the hinge lines.
Claim 7
Dependent Claim
96 words
The method described in claim 1 characterized by contacting the second layer of laminate with a buffer-covered electrode on one side of the high frequency electrode power supply, locating an electrode, that is connected to the other side of the electric power supply, close to the surface of the first layer, and supplying power to the electrodes after bringing one of them into contact with the first layer and pressing the electrode into the first layer until said electrode penetrates substantially to the interface between the two layers along the hinge line of the book cover.
Claim 8
Dependent Claim
63 words
The method described in claim 6 characterized by heating the laminate along areas that correspond with both of the hinge lines of a book cover, and displacing flowable material from the areas of two parallel hinge lines simultaneously on the side of the laminate that is made of the material that is heated to a flowable condition by the high frequency dielectric field.
Claim 9
Dependent Claim
79 words
The method described in claim 1 characterized by depressing material from the hinge line, for the full length of the desired hinge line by an electrode of the desired cross section of the depressed groove that provides the hinge line, and withdrawing the electrode from the material with the temperature of the material cool enough to prevent any substantial flowing back of material into the groove, whereby the entire length of the hinge line is made in one operation.
Claim 10
Dependent Claim
91 words
The method described in claim 8 characterized by heating the material of the first layer to a temperature at which it is flowable under pressure from the electrode, limiting the heating to a temperature that leaves the viscosity of the displaced flowable material high enough to avoid flow back by gravity into the depressed hinge line when the pressure of the electrode is removed, and withdrawing the electrode from the laminate immediately after penetration into the material to the desired hinge depth and without waiting for complete cooling of the laminate.
Claim 11
Dependent Claim
50 words
The method described in claim 1 characterized by closing the circuit of the high frequency dielectric field after pressing the electrode into contact with the first layer of laminate whereby the first layer is heated, and opening the circuit of the high frequency dielectric field after a predetermined heating period.
Claim 12
Dependent Claim
41 words
The method described in claim 10 characterized by adjusting the supply of high frequency electric power for the desired frequency, and using an automatic control for the heating period to insure uniform hinge lines for any selected frequency of power supply.
Claim 13
Dependent Claim
75 words
The method described in claim 1 characterized by forming the laminate as a continuous element with the layers bonded together at their interface, applying the high frequency dielectric field to the laminate to heat the first layer as the laminate advances with continuous motion, applying rolling pressure to the first layer with a wheel that has the desired width and cross section of the hinge line, and cutting the continuous laminate to form book covers.
Claim 14
Dependent Claim
137 words
The Method described in claim 12 characterized by the laminate being formed by bringing together with continuous motion long sheets of material for the respective first and second layers, bonding the sheets together at their areas of contact as they advance with continuous motion, passing the bonded sheets through an accumulation zone, then applying the high frequency electric field to the laminate, providing a width of laminate at least as wide as the width of an open book cover which is to be made from the laminate, passing the laminate continuously through the region of heating and then through a cooling zone, trimming the laminate progressively to the width of the book cover, and cutting lengths from the laminate to form book covers as the laminate travels beyond the cooling zone and beyond the region of trimming.
Claim 15
Dependent Claim
31 words
The method described in claim 12 characterized by making the laminate by applying one layer to the other layer, while both layers are hot enough to fusion bond to one another.
References Cited (Backward Citations)
US2734982A
Cited
US2579488A
Cited
US2638963A
Cited
US2631646A
Cited
US3168424A
Cited
US3668028A
Cited
US3790744A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1978-05-19 | 1978-11-18 | 1979-05-20 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1982-05-19 | 1982-11-18 | 1983-05-20 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1986-05-19 | 1986-11-18 | 1987-05-20 | $7700.00 | Window Closed / Lapsed |