Microcapsules adapted to rupture in a magnetic field to enable easy removal of one substrate from another for enhanced reworkability
US9694337B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jul 11, 2016 |
| Grant date | Jul 4, 2017 |
| Priority date | — |
| Expiry date | Jul 11, 2036 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/31663
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
An enhanced thermal interface material (TIM) gap filler for filling a gap between two substrates (e.g., between a coldplate and an electronics module) includes microcapsules adapted to rupture in a magnetic field. The microcapsules, which are distributed in a TIM gap filler, each have a shell that encapsulates a solvent. One or more organosilane-coated magnetic nanoparticles is/are covalently bound into the shell of each microcapsule. In one embodiment, (3-aminopropyl) trimethylsilane-coated magnetite nanoparticles are incorporated into the shell of a urea-formaldehyde (UF) microcapsule during in situ polymerization. To enable easy removal of one substrate affixed to another substrate by the enhanced TIM gap filler, the substrates are positioned within a magnetic field sufficient to rupture the microcapsule shells through magnetic stimulation of the organosilane-coated magnetic nanoparticles. The ruptured microcapsule shells release the solvent, which dissolves and/or swells the TIM gap filler, thereby reducing the bond strength between the substrates.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.