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
Method and system for simulating superimposition of a non-linearly stretchable object upon a base object using representative images
(4946
Vacuum cleaner filter adapter ring
Filler containing composition and process for production and use thereof
Image capture and identification system and process
Replacing memory pointers with implicit pointers to be used in compiler-generated debug output
Engine RPM control device
  Randomly Featured Patents
Compound screwdriver head
Automatic slot positioning device for camera take-up spool
Light emitting device package and manufacture method of light emitting device package
OX40R binding agents
LCD panel including plurality of display panel parts wrapped around by a thin plastic film envelope with an opening
Battery housing for a radio telephone
System and user interface supporting concurrent application initiation and interoperability
Three-side cutting apparatus
Multilayer fiber reinforced polymeric shaped article
Method and apparatus for encoding video, and method and apparatus for decoding video