PKSC 4300: wettability and treatment (22-49), orientation
(optional), and ca and blown film (optional)
1. Orientation of film:
2. 4 reasons why we orient films:: clarity, crystallinity, dimensional stability/shrinkability, gloss
3. define orientation: process of aligning polymer chains in a direction
4. natural cooling of polymer causes polymer chain orientation, how-
ever stretching the film polymer chains.: random, arranges
5. strength, stiffness, stability
Stretching the film in one or two directions increases the ,
and dimensional (helpful for printing): strength, stiffness,
stability
6. monoaxial: - one direction orientation that offers linear directional tear
1/4
, - when strength only matters in one direction
- machine direction
7. biaxial: - two directions oriented
- offers strength, stiffness, and dimensional stability in two directions
- most print films in laminations are
8. tentering: this method of orientation typically begins with a cast film
9. double bubble: this method of orientation typically begins with a blown film
10. machine direction orientation (monoaxial stretching):
11. sequential biaxial oriented tentering machine:
12. simultaneous biaxial oriented tentering machine:
13. double bubble biaxial orientation:
14. Which has better MD/CD balance? Flat Sequential or Tubular Simultaneous?-
2/4
(optional), and ca and blown film (optional)
1. Orientation of film:
2. 4 reasons why we orient films:: clarity, crystallinity, dimensional stability/shrinkability, gloss
3. define orientation: process of aligning polymer chains in a direction
4. natural cooling of polymer causes polymer chain orientation, how-
ever stretching the film polymer chains.: random, arranges
5. strength, stiffness, stability
Stretching the film in one or two directions increases the ,
and dimensional (helpful for printing): strength, stiffness,
stability
6. monoaxial: - one direction orientation that offers linear directional tear
1/4
, - when strength only matters in one direction
- machine direction
7. biaxial: - two directions oriented
- offers strength, stiffness, and dimensional stability in two directions
- most print films in laminations are
8. tentering: this method of orientation typically begins with a cast film
9. double bubble: this method of orientation typically begins with a blown film
10. machine direction orientation (monoaxial stretching):
11. sequential biaxial oriented tentering machine:
12. simultaneous biaxial oriented tentering machine:
13. double bubble biaxial orientation:
14. Which has better MD/CD balance? Flat Sequential or Tubular Simultaneous?-
2/4