Resources Contact Us Home
Browse by: INVENTOR PATENT HOLDER PATENT NUMBER DATE
 
 
Method for the manufacture of biaxially stretched polyolefin film










Image Number 4 for United States Patent #4261944.

A method is disclosed for the manufacture of a biaxially stretched polyolefin film, particularly a polypropylene film, having improved properties, in which the material is first partially prestretched in a longitudinal direction and, thereafter, simultaneously biaxially (longitudinally and laterally) stretched, the apparatus comprising stretching rollers for effecting partial longitudinal stretching of the film, the rollers being arranged upstream of an assembly for effecting simultaneous biaxial stretching of the film. The speed of the stretching rollers is infinitely variable so as to influence the total degree of film-stretching only by changing the speed of the rollers. The rollers used for longitudinal prestretching are arranged at the inlet section of the biaxial stretching assembly. A system is provided to maintain the film exactly at the temperature required by the film characteristics for stretching, and biaxial stretching is done such that any given point on the film in the region the film is being biaxially stretched undergoes simultaneous biaxial stretching both in the longitudinal and transverse directions of the film.








 
 
  Recently Added Patents
Content shooting apparatus
Synchronizing media streams using time signal(s) from an independent time source
Fan assembly
EvalBinding extension
Multi-function image and video capture device for use in an endoscopic camera system
Barrel-type fish/particle screen with adjustable flow distribution and debris removal
Social based aggregation of related media content
  Randomly Featured Patents
Pyrimidine compounds
Method for changing service quality of a content adaptively
Strong typing of components in RFID business processes
Image transfer device for image forming apparatus
Forward power converter controllers
Process for the addition of thiolates to .alpha.,.beta.-unsaturated carbonyl or sulfonyl compounds
Watch with mesh bracelet
Hierarchical memory system including separate cache memories for storing data and instructions
Process for manufacturing a resin impregnated fishing fly
Material handling system