In-mold labelling a coextruded, stretched and annealed label

US5435963A · kind A · utility

Inventors

• Mitchell J. Rackovan · Mentor, US
• Kushalkumar M. Baid · Mentor, US
• Gerald G. Popely · Mentor, US
• Ronald Lloyd

Key dates

• Filing date: Sep 9, 1992
• Grant date: Jul 25, 1995
• Expiry date: Sep 9, 2012

Classification

• Technology area (CPC Y): Emerging Cross-Sectional Technologies
• CPC primary: Y10T428/249978
• WIPO field: Surface technology, coating
• WIPO sector: Chemistry

Abstract

An oriented polymeric in-mold label film includes a hot-stretched, annealed, linerless self-wound film lamina and has a face layer for printing and a base layer which includes a heat-activatable adhesive. The film may be hot-stretched and annealed at softening and annealing temperatures exceeding the temperature at which the adhesive is activated by passing the film across rolls for imparting heat to and removing heat from the film under controlled time-temperature-direction conditions to heat at least the majority of the thickness of the film to such softening and annealing temperatures without sticking of the adhesive to the rolls. The heat-shrinkability of the film is balanced thickness-wise to minimize curl and allow the film to be printed in conventional label-printing presses. An antistat may be included only in the charge for the base layer which includes the heat-activatable adhesive. In the manufacture of labelled blow-molded containers, sheets and labels formed from the film may be handled at high speeds while maintaining accurate registration and dimensional and positional integrity even in the absence of any reinforcing backing, yet the labels perform well on deformable…