An assembly is disclosed. The assembly includes a cylindrical sleeve and a length of material that is wound upon itself defining a wound roll. The cylindrical sleeve includes an inner surface and an outer surface. The inner surface of the cylindrical sleeve defines a passage extending through the cylindrical sleeve. The length of material includes an inner surface and an outer surface. A portion of the inner surface of the length of material forms a passage extending through the wound roll. The outer surface of the cylindrical sleeve is secured to the portion of the inner surface of the length of material that forms the passage extending through the wound roll. The wound roll forms an upper axial end and a lower axial end. The wound roll is defined by a length extending between the upper axial end and the lower axial end. The cylindrical sleeve forms a distal end and a proximal end. The cylindrical sleeve is defined by a length extending between the distal end and the proximal end. The length of the cylindrical sleeve is greater than the length of the wound roll to thereby define a first portion of the length of the cylindrical sleeve that extends beyond the upper axial end of the wound roll and a second portion of the length of the cylindrical sleeve that extends beyond the lower axial end of the wound roll. Both of the first portion of the length of the cylindrical sleeve and the second portion of the length of the cylindrical sleeve is defined by a Sheffield Smoothness that is less than 350. A method is also disclosed.

The present invention discloses a sheet winding structure to reduce indentation transfer occurring because of sheet thickness or adhesive colloidality of the innermost layer of the sheet. The sheet winding structure comprises: a winding core having an outer surface, wherein the outer surface of the winding core comprises a recess thereon; and a sheet winded over the outer surface of the winding core, wherein a beginning portion of the sheet is disposed in the recess.

The present invention discloses a sheet winding structure to reduce indentation transfer occurring because of sheet thickness or adhesive colloidality of the innermost layer of the sheet. The sheet winding structure comprises: a winding core having an outer surface, wherein the outer surface of the winding core comprises a recess thereon; and a sheet winded over the outer surface of the winding core, wherein a beginning portion of the sheet is disposed in the recess.

The invention provides a heat-shrinkable polyester film roll obtained by winding a heat-shrinkable polyester film on a paper tube with primary shrinkage in the longitudinal direction and a shrinkage rate of 40% or more, wherein the film has a winding length of 1000 to 30000 m, a width of 50 to 1500 mm, and a thickness of 5-30 μm, the thickness irregularity of the film roll in the width direction is 20% or less, the paper tube has an inner diameter of 3 inches with a 0.5 mm or less difference in clearance and a 1700 N/100 mm or more flat compressive strength in the width direction after the film is removed from the film roll, the mean value of the winding hardness of the surface layer part of the film roll in the width direction is 500-850, and the natural shrinkage rate in the longitudinal direction is 2.0% or less.

The invention provides a heat-shrinkable polyester film roll obtained by winding a heat-shrinkable polyester film on a paper tube with primary shrinkage in the longitudinal direction and a shrinkage rate of 40% or more, wherein the film has a winding length of 1000 to 30000 m, a width of 50 to 1500 mm, and a thickness of 5-30 μm, the thickness irregularity of the film roll in the width direction is 20% or less, the paper tube has an inner diameter of 3 inches with a 0.5 mm or less difference in clearance and a 1700 N/100 mm or more flat compressive strength in the width direction after the film is removed from the film roll, the mean value of the winding hardness of the surface layer part of the film roll in the width direction is 500-850, and the natural shrinkage rate in the longitudinal direction is 2.0% or less.

A paper tube that functions as a core of a rolled sheet, the paper tube includes an inside base paper layer at an inside peripheral surface of the paper tube; and an outside base paper layer at an outside peripheral surface of the paper tube, polyphenol and glycerin being impregnated in at least one of the inside base paper layer and the outside base paper layer.

A paper tube that functions as a core of a rolled sheet, the paper tube includes an inside base paper layer at an inside peripheral surface of the paper tube; and an outside base paper layer at an outside peripheral surface of the paper tube, polyphenol and glycerin being impregnated in at least one of the inside base paper layer and the outside base paper layer.

A winding tube for glass fiber yarn has an inner cylinder and an outer polyester fabric covering. The inner cylinder is made of a composite having at least two sheets of polypropylene film bonded together, with each sheet having a plurality of parallel fiberglass filaments embedded within the film of that sheet, and with the filaments of one sheet being at an angle with the filaments of the other sheet. The fabric has a spiral stitching. The tube maintains a cylindrical shape when not subject to deforming forces yet has sufficient flexibility that after a desired amount of glass fiber yarn is wound on the winding tube, the winding tube can be radially collapsed sufficiently to permit the winding tube to be withdrawn from within the yarn package. The winding tube is dimensionally stable at the elevated temperatures to which is likely to be exposed.

A winding tube for glass fiber yarn has an inner cylinder and an outer polyester fabric covering. The inner cylinder is made of a composite having at least two sheets of polypropylene film bonded together, with each sheet having a plurality of parallel fiberglass filaments embedded within the film of that sheet, and with the filaments of one sheet being at an angle with the filaments of the other sheet. The fabric has a spiral stitching. The tube maintains a cylindrical shape when not subject to deforming forces yet has sufficient flexibility that after a desired amount of glass fiber yarn is wound on the winding tube, the winding tube can be radially collapsed sufficiently to permit the winding tube to be withdrawn from within the yarn package. The winding tube is dimensionally stable at the elevated temperatures to which is likely to be exposed.

A paper bobbin for winding yarn has an outer periphery provided with two annular protruding portions each adjacent to one of two ends of the paper bobbin respectively; since each protruding portion is protruded a height from the outer periphery of the paper bobbin, the two annular protruding portions may help the paper bobbin not only to lower the frequency of fiber breakage at initial stage of a yarn winding operation, but also to contribute to get a high quality of yarn and an increase in yield.