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
Heat stable variants of plant adenosine diphosphate glucose pyrophosphorylase small subunit
Resonant oscillator with start up and shut down circuitry
Printer driver, printer control method, and recording medium
Wireless communication power control
Image coding apparatus and image decoding apparatus
Manufactured product configuration
Low offset, fast response voltage controlled current source and controlling method thereof
  Randomly Featured Patents
Semiconductor laser device and method of manufacturing the same
Combined cup and cap
Racket frame
Transmission line for dielectric measurement and dielectric measuring device having the transmission line
Arrangement in a gripper mechanism for a free pipe/rodlike end portion of a downhole tool
Clothes rack
Suspension ceiling clips and installation method
Coupler height adjuster for railway cars
Aroma diffuser
Image processing apparatus and image processing program