Plastic vessel having oriented coating and process for preparation thereof
AssigneeToyo Seikan Kaisha, Ltd.
InventorsYoshitsugu Maruhashi, Isao Tanikawa, Sadao Hirata
Life of this patent
Estimating the term…
Loading patent…
AssigneeToyo Seikan Kaisha, Ltd.
InventorsYoshitsugu Maruhashi, Isao Tanikawa, Sadao Hirata
Estimating the term…
Disclosed is a coated oriented plastic vessel formed by subjecting a parison, preform or sheet comprising a molecularly orientable thermoplastic resin substrate and a coating layer of a vinylidene chloride copolymer formed on at least one surface of said substrate to a draw-molding operation such as biaxial draw-blow-molding or draw-forming, wherein the coating layer of the vinylidene chloride copolymer has such a molecular orientation tht the sum of two-dimensional orientation coefficients (l+m) in the axial direction and circumferential direction is at least 0.03 as measured according to the polarized light fluorometry and the coating layer is not substantially peeled at the low-temperature burst test conducted at -5.degree. C. This coated oriented plastic vessel is prepared by a process comprising coating an aqueous latex of a vinylidene chloride copolymer on at least one surface of a parison, preform or sheet composed of a molecularly orientable thermoplastic resin, drying the coated latex to form a coated structure and subjecting the coated structure to a draw-molding operation such as biaxial draw-blow-molding or draw-forming at a temperature higher than the glass transition temperature of the vinylidene chloride copolymer but lower than the melting point of the vinylidene chloride copolymer, at which temperature draw-molding of said thermoplastic resin is possible, to thereby from the coated structure into a shape of a vessel while drawing the coating layer.
A process for the preparation of coated oriented plastic vessels, which comprises coating an aqueous latex of a vinylidene chloride copolymer on at least one surface of a bottomed parison composed of amorphous polyethylene terephthalate, drying the coated latex to form a coated structure provided with an outermost surface coating layer on a polyethylene terephthalate substrate and subjecting the coated structure to biaxial draw-blow-molding at a temperature higher than the glass transition temperature of the vinylidene chloride copolymer but lower than the melting point of the vinylidene chloride copolymer under such a condition that the temperature of the coating layer of the coated structure is lower by at least 5.degree. C. than the average temperature of the polyethylene terephthalate substrate, at a draw ratio in the axial direction of 1.10 to 20 and at a draw ratio in the circumferential direction of 1.20 to 50, at which temperature draw-molding of said parison is possible, to thereby form the coated structure into a shape of a vessel while drawing the coating layer so that the coating layer of the vinylidene chloride copolymer has such a molecular orientation that the sum of two-dimensional orientation coefficients (l+m) in the axial direction and circumferential direction is at least 0.4 as measured according to the polarized light fluorometry and the coating layer is not substantially peeled at the low-temperature burst test conducted at -5.degree. C.
Dependencies are inferred from the claim text.