{
  "abstract": "The fatigue failure (F/F) test is an important method for evaluating hair strength. In this study, we evaluate commercial European hair after up to four bleaches. F/F-data were directly fitted using a two-parameter cumulative Weibull distribution (CWD) function, described by lifetime index (λ) and shape factor (β). Fibre samples taken from treated tresses (T) exhibited stable F/F behaviour across multiple treatments, while treated single fibres (S) showed early breakage if treated more than twice. We attribute this effect mainly to the liquor ratio during treatment. In this context, we suggest a strategy to estimate a treatment-related apparent decay constant for λ. The constant for T-samples was determined as kn = 0.095. This is consistent with DSC results in the literature for the denaturation enthalpy. This may indicate an important role for intermediate filaments in fatigue failure. To possibly establish a link with hair breakage during combing, we investigated the properties of the hazard function for T-samples based on β = 0.92. The model calculations indicate that early failure risks are low but increase exponentially with repeated bleaches. The correspondence with the literature results leads to the hypothesis of a relationship between F/F and combing tests.",
  "abstract_shown": true,
  "affiliations": [
    "Department of Materials, School of Natural Sciences, The University of Manchester, Manchester M13 9PL, UK",
    "Henkel Consumer Brands, Henkel AG &Co KGaA, D-22761 Hamburg, Germany",
    "Department of Chemistry, University of Hamburg, Martin-Luther-King Platz 6, D-20146 Hamburg, Germany"
  ],
  "article_type": null,
  "arxiv": null,
  "author_total": 6,
  "authors": [
    {
      "affs": [
        0
      ],
      "name": "Franz J. Wortmann"
    },
    {
      "affs": [
        1
      ],
      "name": "Jessica Welzel"
    },
    {
      "affs": [
        1
      ],
      "name": "Leila Berriche"
    },
    {
      "affs": [
        1
      ],
      "name": "Svitlana Sirenko"
    },
    {
      "affs": [
        0
      ],
      "name": "Gabriele Wortmann"
    },
    {
      "affs": [
        2
      ],
      "name": "Volkmar Vill"
    }
  ],
  "bibtex": "https://research.draconitic.com/paper/aprejtnw273vn.bib",
  "cited_by": 0,
  "doi": "10.3390/cosmetics13050231",
  "fulltext_url": "https://www.mdpi.com/2079-9284/13/5/231",
  "id": "aprejtnw273vn",
  "issns": [
    "2079-9284"
  ],
  "landing_url": "https://doi.org/10.3390/cosmetics13050231",
  "language": "en",
  "licence": "CC-BY",
  "licence_label": "CC BY",
  "licence_source": "journal",
  "licence_url": "https://creativecommons.org/licenses/by/4.0/",
  "metadata_licence": null,
  "native_subjects": [
    [
      "lcc",
      "QD1-999"
    ],
    [
      "openalex",
      "2215|Dyeing and Modifying Textile Fibers"
    ]
  ],
  "openalex": "W7211924964",
  "pdf_url": null,
  "pmcid": null,
  "pmid": null,
  "published": "2026-09-01",
  "publisher": "MDPI AG",
  "ris": "https://research.draconitic.com/paper/aprejtnw273vn.ris",
  "sources": [
    {
      "first_seen": "2026-10-31T14:21:26Z",
      "native_id": "03b278d209bb4264b3ebd8eb345820ca",
      "source": "doaj",
      "url": "https://doi.org/10.3390/cosmetics13050231"
    }
  ],
  "subjects": [
    {
      "field": "chemistry",
      "origin": "lcc:QD1-999",
      "subfield": "general"
    },
    {
      "field": "medicine",
      "origin": "journal-openalex:2708|Skin Protection and Aging",
      "subfield": "general"
    }
  ],
  "title": "Multiple Bleaching of Hair: Fatigue Failure Investigations and Weibull Analyses",
  "title_text": "Multiple Bleaching of Hair: Fatigue Failure Investigations and Weibull Analyses",
  "type": "peer-reviewed",
  "updated_at": "2026-10-31T14:21:26Z",
  "url": "https://research.draconitic.com/paper/aprejtnw273vn",
  "venue": "Cosmetics",
  "versions": []
}