Cellulose Fibers
Patent No. EP4219808 (titled "Cellulose Fibers") was filed by Circulose on Dec 5, 2017. The application was issued on Jul 23, 2025.
Patent Summary
A cellulose-based fiber, manufactured via a Viscose or Lyocell process, comprises a mixture of cellulose dissolving pulp and a recycled cellulose textile material. The recycled material is treated to swell the cellulose under reducing conditions using at least one reducing additive present during at least part of the swelling process at a pH between 9 and 13.5. Additionally, the recycled material undergoes at least one bleaching step: either alkaline oxygen bleaching at a pH range of 9–13.5 or acidic ozone bleaching at a pH below 6. This specific treatment of the recycled textile component, when blended with dissolving pulp, is intended to increase the tensile strength of the resulting regenerated cellulose fiber.
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Dossier Documents
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Date
Description
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EP4219808
- Application Number
- EP23154979A
- Filing Date
- Dec 5, 2017
- Status
- Granted And Under Opposition
- Jun 20, 2025
- Publication Date
- Jul 23, 2025
- External Links
- Slate, Register , Google Patents