IPF‑100K is a seaweed‑derived cosmetic ingredient from Porphyra yezoensis, containing the polysaccharide porphyran refined from domestically sourced Japanese seaweed. Porphyran forms a protective film, provides moisturization, exhibits anti‑inflammatory activity, and helps inhibit UV‑induced erythema, making it suitable for skin, scalp, sun‑care, and damaged‑hair applications.