Devices for reducing or eliminating defects in polymer workpieces
View Patent ↗The present disclosure provides a novel suspension device used in producing a composition, such as, but not limited to, a polyimide composition. The suspension device in its most general form comprises a support element and an attachment element. The attachment element is in communication at one of its ends with the support element and at the other with a workpiece, such as a poly(amic acid) or polyimide workpiece. The suspension device may further comprise additional elements. The suspension device maintains the workpiece in a suspended state during processing so as to reduce or eliminate processing-related defects.
1. A suspension device for suspending the polyimide or polyamic acid workpiece during processing so as to reduce or eliminate processing-related defects comprising:
(a) at least one support element, the support element further comprising a receiving point;
(b) a plurality of attachment elements, said plurality of attachment elements being secured to the receiving point at a first end and to the workpiece at a second end wherein the attachment elements are constant tension springs;
(c) a polyimide or polyamic acid workpiece comprising a plurality of attachment points, each said attachment point comprising an opening and a reinforcing structure, wherein the attachment elements are secured to the workpiece at the attachment points; and
wherein such processing results in shrinkage of the workpiece.
2. The device of claim 1 where the attachment elements are reversibly secured to the workpiece, the support element or both the workpiece and the support element.
3. The device of claim 1 where a single support element secures 1 attachment element.
4. The device of claim 1 where a single support element secures more than 1 attachment element.
5. The device of claim 1 where the support element further comprises an extension portion, the extension portion having at least one arm.
6. The device of claim 1 where a single support element secures more than 1 attachment element.
7. The device of claim 1 where said support element further comprises a base secured to the at least one support element.
8. The device of claim 1 where the suspension device further comprises a base, the base comprising at least one attachment point for receiving the at least one support element.
9. The device of claim 8 where the support elements are reversibly received by the attachment points.
10. The device of claim 1 where the processing-related defect renders the workpiece unsuitable for use.
11. The device of claim 1 where the processing is imidization.
12. The device of claim 11 where the processing-related defects are transformation-related defects or substrate retention-related defects.
13. The device of claim 12 where the transformation-related defect is a cracking, a tearing, a curling, a warping, or a mechanical anisotropy of the workpiece.
14. The device of claim 12 where the substrate-retention related defect is a cracking of the workpiece, a tearing of the workpiece, an inability to remove the workpiece from the substrate, or a defect associated with the use of an ancillary agent used to aid in the removal of the workpiece from the substrate.
15. The device of claim 14 where the ancillary agent is a release interface agent and the defect associated with the use of an ancillary agent is a haziness, a cloudiness, or a product deformation.
16. The device of claim 1 where the workpiece is in the form of a film or membrane.
17. The device of claim 1 where the suspending dissipates at least a portion of a stress that is generated during processing.
18. The device of claim 11 where the suspending dissipates at least a portion of a stress that is generated during imidization.
19. The device of claim 1 where the at least one support element has a length, l, and the attachment elements have a length, L, such that the workpiece is suspended during processing.
20. The device of claim 1 where the device is operated in a continuous mode or a batch mode.
21. The device of claim 1 wherein the plurality of attachment elements are secured to the workpiece.
22. The device of claim 1 wherein the plurality of attachment elements are spiral-coiled-type constant tension springs.