An object of the present invention is to provide a keratin softening composition which can effectively soften nail cuticle and skin keratin, and which has reduced skin irritation and corrosivity. A keratin softening precursor composition comprising bioactive glass and water. A keratin softening composition comprising an extract from bioactive glass. The keratin softening composition may further include a humectant and a thickener. The effect of sodium ions and calcium ions released from the bioactive glass can effectively soften the cuticle of the nail and the skin of the skin. [Selection] Figure 1【課題】爪の甘皮及び皮膚の角質を効果的に軟化することが出来る、皮膚刺激性、腐食性の低減された角質軟化組成物の提供。【解決手段】生体活性ガラス及び水を含む、角質軟化前駆組成物。生体活性ガラスからの抽出物を含む、角質軟化組成物。該角質軟化組成物は、保湿剤及び増粘剤をさらに含むことができる。生体活性ガラスから放出されたナトリウムイオン及びカルシウムイオンの効果により爪の甘皮及び皮膚の角質を効果的に軟化することが出来る。【選択図】図１
