PROBLEM TO BE SOLVED: To provide an agent for increasing thickness of hair, capable of not only improving an appearance of the hair, but also achieving increase in volume of the hair by substantially thickening the hair one by one and increasing weight of the hair, for the purpose of improving sparse hair, and capable of preventing the hair from losing the above effects even when the hair is washed in daily life, and to provide a method for increasing the thickness of the hair.SOLUTION: The hair treatment agent contains a protein and is used for increasing the hair. The hair treatment agent is composed of two agents comprising a reduction treatment agent containing the protein and an oxidation treatment agent. It is preferable that a content of the protein is 1-70 wt.% based on the reduction treatment agent and the protein comprises a hydrolyzed keratin protein and/or a hydrolyzed silk protein. The method for increasing the thickness of the hair comprised applying the reduction treatment agent containing the protein to the hair and then applying the oxidation treatment agent thereto.COPYRIGHT: (C)2007,JPO&INPIT【課題】薄毛を改善するために、見た目の改善のみでなく、実質的に毛髪一本一本を太くし、重量をも増大させることでボリュームアップを達成し、且つ、日常生活における洗髪によってもその効果を失うことの無い毛髪の太さ増大剤と毛髪の太さを増大する方法を提供する。【解決手段】毛髪の増大を目的とした、蛋白質含有の毛髪処理剤。毛髪処理剤は蛋白質を含有した還元処理剤と酸化処理剤との二剤からなる。還元処理剤に対する蛋白質の含有量が1~70重量%であり、該蛋白質は加水分解ケラチン蛋白質及び/又は加水分解シルク蛋白質であることが好ましい。また、蛋白質を含有する還元処理剤を毛髪に塗布した後に、酸化処理剤を塗布することを特徴とする毛髪の太さを増大する方法である。【選択図】なし
