Patent ID: 11919216
Assignee: TOYOBO CO., LTD.
Field: Other special machines (Mechanical engineering)
Classification: CPC B  C | IPC B  C

Claim 0:
1. A roll of a white heat-shrinkable polyester-based film comprising at least one layer of a white polyester-based resin layer containing titanium oxide and satisfying the following requirements (1) to (6):
(1) the length of the film is 1000 m or more and 20000 m or less and the width of the film is 400 mm or more and 10000 mm or less;
(2) the heat-shrinkage percent change in a main shrinkage direction is 50% or more and 85% or less, wherein the heat-shrinkage percent change is measured according to a hot water treatment of a treatment temperature of 98° C. and a treatment time of 10 seconds;
(3) the difference in percentage points between the maximum and minimum heat-shrinkage percent change in the main shrinkage direction among samples is 0 or more and 1.5 or less, wherein the heat-shrinkage percent change is measured according to the hot water treatment of a treatment temperature of 98° C. and a treatment time of 10 seconds and the samples are taken from each part of the film divided into five in the film width direction;
(4) the difference in percentage points between the maximum and minimum heat-shrinkage percent change in the main shrinkage direction among samples is 0 or more and 1.5 or less, wherein the heat-shrinkage percent change is measured according to the hot water treatment of a treatment temperature of 98° C. and a treatment time of 10 seconds and the samples are taken from the film every 100 m in the film longitudinal direction from the place forming surface layer of the roll of the white heat-shrinkable polyester-based film to the starting place of winding the film;
(5) the difference between the maximum and minimum apparent specific gravity among samples is 0 g/cm3 or more and 0.01 g/cm3 or less, wherein the samples are taken from each part of the film divided into five in the film width direction; and
(6) the difference between the maximum and minimum apparent specific gravity among samples is 0 g/cm3 or more and 0.010 g/cm3 or less, wherein the samples are taken from the film every 100 m in the film longitudinal direction from the place forming surface layer of the roll of the white heat-shrinkable polyester-based film to the starting place of winding the film,
wherein
the white polyester-based resin layer comprises a polyester consisting essentially of (i) a terephthalic acid component, (ii) an ethylene glycol component, and (iii) a second polyol component consisting of
neopentyl glycol, 1,4-cyclohexanedimethanol, or a combination thereof.