The invention provides a heat shrinkable polyester film which has (1) a hot-water heat shrinkage of not less than 55% and not more than 90% in a main shrinking direction of the film when dipped in hot water at 98 C.; (2) a hot-water heat shrinkage of not less than 5% and not more than 12% in a direction orthogonal to the main shrinking direction of the film when dipped in hot water at 98 C.; (3) a difference in specific heat capacity C.sub.p between at a lower and a higher temperature than Tg of not less than 0.1 J/(g.Math. C.) and not more than 0.7 J/(g.Math. C.) when a reverse heat flow is measured with a temperature modulated DSC; and (4) a tensile breaking strength of not less than 70 MPa and not more than 150 MPa in the direction orthogonal to the main shrinking direction of the film.

A film layer is disclosed that is capable of shrinking when subjected to energy, such as heat. The film layer, for instance, can be formed and then stretched in one or two directions at a relatively low temperature. In particular, the film is stretched while the film layer is at a temperature near the glass transition temperature of the polymer used to form the film. Drawing the film at a relatively low temperature has been found to improve the shrink properties of the film. In one embodiment, the film layer is comprised of a non-modified polyester, such as polyethylene terephthalate. For example, the polyethylene terephthalate can be made by reacting terephthalic acid with ethylene glycol or polyethylene glycol.

A heat shrink tubing, which can be readily peeled in the longitudinal direction after use (e.g., to remove the heat shrink tubing from an underlying material) is provided herein. The heat shrink tubing can be of various compositions, and generally is produced from at least one fluorinated, copolyrneric resin. The tubing can exhibit desirable physical properties such as good optical clarity (e.g., translucency or transparency) and/or peelability, exhibiting one or more of complete, straight, and even peeling along a given length of tubing.

A cylindrical shrink label is provided with a heat-shrinkable label base material; and a joint formed by cylindrically forming the label base material so that the edges thereof overlap, and then solvent welding the inner surface of the outside edge, which is positioned on the outside of the cylinder, and the outer surface of the inside edge, which is positioned on the inside of the cylinder. A resin layer, which is soluble in a hot alkaline aqueous solution, is formed on the abovementioned inner surface and/or the abovementioned outer surface, which form the joint.

The present invention provides a multilayer heat shrinkable film incorporating an oxygen barrier material and layer containing a styrene polymer or blend of styrene polymers, where the shrinkage of the film in at least one of MD, TD is at least 30% at 90 C. The invention is further directed to a method of manufacturing a bag from said multilayer heat shrinkable film.

The invention provides a heat-shrinkable polyester-based film comprising ethylene terephthalate units, constituent units derived from at least one monomer which forms an amorphous component, and constituent units derived from butanediol. The amount of the constituent units derived from at least one monomer which forms an amorphous component is 18 mol % or more, and the amount of the constituent units derived from butanediol is 1 to 25 mol % based on 100 mol % of all polyester resin components. The heat-shrinkable polyester-based film is characterized by particular values for the secondary shrinkage ratio of the film, the hot-water heat shrinkage ratio of the film, and the reversing heat capacity difference before and after the glass transition temperature of the film.

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.

A heat shrink tubing, which can be readily peeled in the longitudinal direction after use (e.g., to remove the heat shrink tubing from an underlying material) is provided herein. The heat shrink tubing can be of various compositions, and generally is produced from at least one fluorinated, copolymeric resin. The tubing can exhibit desirable physical properties such as good optical clarity (e.g., translucency or transparency) and/or peelability, exhibiting one or more of complete, straight, and even peeling along a given length of tubing.

A shrinkable core (100) for inserting in a mold (200) for forming a precast load bearing wall panel having a cavity, the shrinkable core (100) comprises a first wall (110) and a second wall (120), a first side element (112) and a second side element (122), and a spacing element (130). The first wall (110) and second wall (120) are spaced from each other by a first distance (d1) to define an internal region (115) in-between. The first side element (112) and the second side element (122) are arranged to close opposite edge portions of the spaced first wall (110) and second wall (120) such that fluid concrete cannot pass the opposite edge portions to get into the internal region (115), the first side element (112) and second side element (122) being spaced by a second distance (d2). The spacing element (130) is configured to vary at least one of the first distance (d1) and the second distance (d2) such that a circumference along the first and second walls (110, 120) and the first and second side elements (112, 122) shrinks monotonically with lowering said at least one distance.

A method for coating a surface of an aircraft is provided. The method comprises the steps of cutting to size at least one film section from a shrinkable film material in such a manner that the film section relative to a surface section of the aircraft, which surface section is to be coated with the film section, comprises an overmeasure that is determined by the degree of shrinkage of the film material; applying the film section and a functional coating to the surface section so that the functional coating is arranged between the surface section and the film section; and shrinking the film section by heating it to a temperature that corresponds at least to the shrinkage temperature of the film section and at least to the flow temperature of the functional coating until the contours of the film section largely conform to the contours of the surface section.