A general term for a group of plant polyphenol compounds that bind proteins and metal ions. When cloth is treated with a metal salt before or after dyeing, tannin is said to turn into a metal chelate, and its hydroxyl groups are said to bridge dye and fibre and help fix the colour.
The limitations noted for some sources are recorded in Japanese only — see the Japanese edition.
Tannin ・propertystates that tannin tends to polymerize under alkaline conditions, and that the resulting polymer can grow larger and become less water-soluble (discussed in relation to the lime-bearing spent dye liquor showing an alkaline pH of about 9)preliminary
Scope: discussion of the precipitate observed when centrifuging the lime-bearing spent dye liquor (pH about 9)
Notes that the spent dye liquor is alkaline (about pH 9) due to residual lime, that tannin tends to form polymers under alkaline conditions, and that these polymers may grow further and become poorly soluble.
Tannin works by Chelation between tannin and a metal saltcontextual
States such tannins turn into metal chelates once the substrate is pre- or post-treated with a metal salt.
Source: Bio-mordants: a review （Hüseyin Benli, 2024） ・Introduction 節、冒頭から4文目付近 ・textbook ・ checked against the source by AI
Tannin ・mechanismStates the phenolic hydroxyl groups in tannin create crosslinks between the dye and the fibre, helping to fix the colour.contextual
States the hydroxyl groups of the phenols in tannins are crucial for creating crosslinks with various dyes and fibres.
Source: Bio-mordants: a review （Hüseyin Benli, 2024） ・Introduction 節、Pisitsak et al. 2018を引く文 ・textbook ・ checked against the source by AI
Unripe persimmon juice contains Tannincontextual
States that the astringent component of unripe persimmons is tannin.
Source: 갈옷 （장현주(제주대학교 교수), 2022） ・本文各所 ・institutional summary ・ checked against the source by AI
Myanmar ・mechanism ― Tannincontextual
Mud combined with tannin-rich bark yields an iron-rich black; the site emphasises the importance of studying anthraquinone-producing plants in the region.
Source: Plants & Natural Dyes - Weaving Ecologies （Jackie Andrews-Udall） ・'It is therefore significant to favour the study of anthraquinone producing plants above all in this region, alongside the practise of using mud in combination with tannin-rich tree barks to obtain the iron rich black'の一文 ・practitioner's record ・ checked against the source by AI
Tapa (barkcloth) making includes Tannin (as a class)supported
It states that non-specific tree tannins were found as the sole colourant in 11 of the 52 samples, and in combination with other colourants (such as noni or turmeric) in a further 9; while there was little evidence of traditional metal mordanting, historical records are cited as reporting that tree tannins were used as a mordant.
Tannin ・causesStates that tannin-containing (bio-)mordants have been shown to enhance the light fastness of dyes such as turmeric, henna, madder and pomegranate rind, according to this review.contextual
Scope: A review's summary of multiple prior studies
States that natural mordants such as tamarind seed coat and Emblica officinalis tannins have been shown to enhance the light-fastness properties of dyes including turmeric, henna, madder and pomegranate rind.
Source: Understanding the Fastness Issues of Natural Dyes （Tarikul Islam, Kazi Md. Rashedul Islam, Shahin Hossain, M. Abdul Jalil, M. Mahbubul Bashar, 2024） ・本文"tannins, have been shown to enhance the light fastness properties..."の一文 ・textbook ・ checked against the source by AI
Tannin ・propertyAn explanatory article describes tannins as the general name for plant-derived polyphenol components that react with proteins, metal ions, alkaloids and the like to form insoluble precipitates.contextual
Scope: A general definition in an explanatory article on the chemistry of kakishibu (Kagaku to Kyoiku); background for statements that kakishibu becomes insoluble.
Describes tannins as plant-derived polyphenol components, the general name for substances that react with proteins, metal ions, alkaloids and the like to form insoluble precipitates.
When the same cloth is dipped alternately in a gallnut (tannic-acid) solution and in ferrous-sulfate versus ferrous-acetate solutions, what differences in colour and fastness result from black-dyeing?🧪 testable at home
Shimizu et al. (1988) found that the resulting hue varies with the iron salt used; at home, one could compare the colour from gallnut (or tannic-acid reagent) combined with different readily available iron mordants (e.g. a vinegar-and-rusty-nail solution resembling kanemizu) on the same cloth.
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