Patent · US Expired

Heat weld indicator for thermoplastic roofing membrane

US6055786A · kind A · utility

42Cited by
19References
29Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMay 30, 1996
Grant dateMay 2, 2000
Priority date
Expiry dateMay 30, 2016

Classification

  • Technology area (CPC E)Fixed Constructions
  • CPC primaryE04D5/149
  • WIPO fieldCivil engineering
  • WIPO sectorOther fields

Abstract

A roofing membrane heat seal indicator provides a positive, visually perceptible indication that a joint or seam has been raised to a sufficiently high temperature to achieve a proper seal. The heat seal indicator is applied adjacent and parallel to an edge of a roofing membrane which will be arranged on a roof to form the upper (exposed) surface of an overlapping membrane seam. As the adjacent surfaces of the overlapped membranes are heated, heat passes through the membrane to the heat seal indicator. The heat seal indicator may be a temperature sensitive ink pigmented with material that changes color upon being subjected to a temperature indicating that the membrane surface has been subjected to a sufficiently high temperature to achieve an appropriate seal. Alternatively, the indicator may be an adhered layer of a ground or flaked polymer, such as polyethylene, which is initially opaque but melts to become translucent, thereby indicating obtainment of a proper sealing temperature. This indicator may be combined with a white or colored strip which enhances the change in the polyethylene. Another alternative comprehends the combination of a group indicator and molten polyethylene …

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.