The invention provides a heat-shrinkable polyester film with high mechanical strength in a width direction that is orthogonal to the main shrinking direction and high tensile rupture elongation in the film width direction after being subjected to an aging treatment in a high-temperature environment. The heat-shrinkable polyester film is made from a polyester resin containing ethylene terephthalate as the main component and a monomer component that can serve as an amorphous component in an amount of 0 mol % or more and less than 1 mol % relative to the total amount of polyester resin components.

An automotive assembly line tool system and method utilizing a heat-shrinkable bumper disposed around a portion of an assembly line tool for absorbing kinetic energy between the portion of the tool and a work-piece on an assembly line. The bumper may be a chemically cross-linked polyolefin heat-shrinkable material having a shore D hardness of 42 or less after being heat-shrunk. The bumper may be a tubular bumper that has a continuous outer surface around its circumference and a heavy wall that is highly split-resistant. The bumper may have a life term of at least one year in an automotive assembly line environment. By protecting the tools and equipment, chips and scratches on a work-piece on the assembly line may be reduced.

An object of the present invention is to provide a tube which can be easily torn and has a large heat-shrinkability at a low temperature. The tube of the present invention is a heat-shrinkable tube having tearability, including a mixture of a fluorine resin and a different kind of resin from the fluorine resin, in which an amount of change in loss energy, E loss, with change in temperature from 175 C. to 185 C. is a positive value.

The invention provides a polyester sealant film having at least one of a heat sealing layer and a heat resistant layer, wherein each layer consists of a polyester component containing ethylene terephthalate. The polyester sealant film has (1) a heat sealing strength of the heat sealing layers of 8-20 N/15 mm; (2) a difference in reversible heat capacity (Cp) for the heat sealing layer of 0.5-1.1 J/g/K; (3) a Cp for the heat resistant layer of 0.1 to less than 0.6 J/g/K; (4) a fold holding angle of 20-60 degrees; (5) a smaller curvature radius of 50-300 mm in a longitudinal or widthwise direction; and (6) a heat shrinkage ratio of 5% to 5% in both longitudinal and widthwise directions. The invention also provides a laminate comprising at least one layer of the polyester sealant and a packaging bag comprising the laminate.

Disclosed is a heat-shrinkable polyester film having a heat shrinkage initiation temperature of 60 C. or lower, a glass transition temperature (Tg) of 77 C. or lower and a heat shrinkage rate of 2% or more at 60 C. which has relatively low glass transition temperature and heat shrinkage initiation temperature, and thus can be useful as a label for a high-density polyethylene (HDPE) container and the like.