← Back to Patent Explorer
US4364892A Expired / Lapsed US ⏱️ 0.0 years remaining

Process for surface treatment of foamed sheets

Assignee: Cellofoam Deutschland GmbH
•
Filing: 1979-07-20
•
Granted: 1982-12-21
•
Expires: 1999-07-20
📄 Original PDF 🌐 Google Patents 🔄 Sync Now

Abstract

Abstract A process for the continuous modification of the surface portion only of a foamed plastic web to impart high mechanical resistance with retention of air permeability and elasticity comprises preheating the web to a temperature below its melting point, passing the preheated web through the nip of a calendar and withdrawing the web from the calender under tension. The calendar comprises a pressure roller heated to a temperature above the melting point of the web and a backing roller which is not heated.

Inventors

  • 👤 Helmut Rehlen
  • 👤 Jurgen Roellinghoff

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-30 03:28
CPC Classifications
B; B29; B29C; B29C59/00; B29C59/02; B29C59/04; B29C43/00; B29C43/22; B29C43/30; B29C43/305; B29C44/00; B29C44/34; B29C44/56; Y; Y10; Y10T; Y10T156/00; Y10T156/10; Y10T156/1002; Y10T156/1007; Y10T156/1023; Y10T156/1052; Y10T156/1084; Y10T156/1085; Y10T156/1087; Y10T428/00; Y10T428/24; Y10T428/24942; Y10T428/24992; Y10T428/249921; Y10T428/249953; Y10T428/249961; Y10T428/249975; Y10T428/249981; Y10T428/31

Claims Analysis

Total Claims: 5
Claim 1
Independent Claim 157 words
A process for the continuous modification of the surface portion only of a foamed plastic web to impart high mechanical resistance with retention of air permeability and elasticity, which comprises preheating the web to a temperature below its melting point, then subjecting the preheated web to shock heating by means of a device disposed at a distance of 5 to 10 mm from the web and at a temperature of from 150° C. to 300° C., and then passing the preheated and shock heated web through the nip of a calender comprising a pressure roller and a backing roller, the pressure roller being heated to a predetermined temperature above the melting point of the web and up to 500° C., the web being fed to the calender nip in such a way that it is looped around the pressure roller through an angle of at least 30° and is then withdrawn from the calender and wound up.
Claim 2
Dependent Claim 157 words
A process for the continuous modification of the surface portion only of a foamed plastic web to impart high mechanical resistance with retention of air permeability and elasticity, which comprises preheating the web to a temperature below its melting point, then subjecting the preheated web to shock heating by means of a device disposed at a distance of 5 to 10 mm from the web and at a temperature of from 150° C. to 300° C., and then passing the preheated and shock heated web through the nip of a calender comprising a pressure roller and a backing roller, the pressure roller being heated to a predetermined temperature above the melting point of the web and up to 500° C., the web being fed to the calender nip in such a way that it is looped around the pressure roller through an angle of at least 30° and is then withdrawn from the calender and wound up.
Claim 3
Dependent Claim 30 words
A process as claimed in claim 1, wherein the web, after preheating and shock heating, and before entering the calender nip, is compressed by means of a pair of rollers.
Claim 4
Dependent Claim 32 words
A process as claimed in claim 2, wherein the web, after being preheated, shock heated and compressed, and before entering the calender nip, is exposed to the action of an auxiliary heater.
Claim 5
Dependent Claim 23 words
A process as claimed in claim 1, wherein the pressure roller is heated from the interior and is additionally heated from the exterior.

References Cited (Backward Citations)

US3062698A Cited
US3239399A Cited
US3205120A Cited
US3422172A Cited
US3582430A Cited
US3890414A Cited
US3998683A Cited
US4091154A Cited
US4070435A Cited
US4280978A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1985-12-20 1986-06-21 1986-12-21 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1989-12-20 1990-06-21 1990-12-21 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1993-12-20 1994-06-21 1994-12-21 $7700.00 Window Closed / Lapsed

Assigned Categories & Tags

No categories assigned to this patent yet.

Assign Category Tag