Back to results
US 5,510,075 AGranted
Mold process for syndiotactic polypropylene
AssigneeBecton, Dickinson and Company
InventorsShel McGuire, Joel L. Williams
Life of this patent
Estimating the term…
Abstract
A molding process for syndiotactic polypropylene includes holding the melt at a process temperature of about 27.degree. to 77.degree. C. to achieve a cycle time of less than 150.degree. C. and a haze value for a 2 mm thick article of less than 38%.
Claims5
A process for molding syndiotactic polypropylene comprising:
- a) injecting a melt of syndiotactic polypropylene into a mold maintained at a temperature sufficient to keep said melt in the mold at a process temperature of 49.degree. to 77.degree. C.;
- b) holding said melt at said process temperature until it crystallizes into an article having the shape of said mold;
- and
- c) ejecting said article from said mold wherein process steps (a) and (b) are complete in a cycle time of 50 sec. or less and said article has a haze value of 31% or less.
1 more element
A process for molding syndiotactic polypropylene comprising:
- a) injecting a melt of syndiotactic polypropylene into a mold maintained at a temperature sufficient to keep said melt in the mold at a process temperature of 49.degree. to 70.degree. C.;
- b) holding said melt at said process temperature until it crystallizes into an article having the shape of said mold;
- and
- c) ejecting said article from said mold wherein process steps (a) and (b) are complete in a cycle time of 39 sec. or less and said article has a haze value of 26% or less.
1 more element
Dependencies are inferred from the claim text.