Bleaching and dyeing; fluid treatment and chemical modification – Chemical modification of textiles or fibers or products thereof – Proteinaceous fibers
Patent
1989-09-25
1998-08-18
Johnson, Jerry D.
Bleaching and dyeing; fluid treatment and chemical modification
Chemical modification of textiles or fibers or products thereof
Proteinaceous fibers
8405, 8406, 8501, 8DIG13, D06P 500, D06M 1300
Patent
active
057953546
DESCRIPTION:
BRIEF SUMMARY
BACKGROUND OF THE INVENTION
1. Field of the Invention
The present invention relates to the application of dye to keratin fibres, and to products incorporating such fibres.
2. Description of the Related Art
Wool and other keratinous fibres are usually dyed from acidic liquors that often contain various reagents, in addition to dyes. In conventional wool dyeing, the temperature of the dyebath is usually increased progressively to around 95.degree.-100.degree. C., where it is maintained for a time, up to several hours, that depends on the particular dyes that are being applied. These dyeing procedures can consume large amounts of energy. Furthermore, a significant degree of fibre damage can be caused, particularly if the pH of the dyebath is far removed from the iso-electric region of wool (ca pH 4-5). The object of the present invention is to enable wool to be dyed in fibre, yarn, fabric or garment form under milder conditions than are now commonly used. The milder conditions may be shorter times and/or lower temperatures than those usually required in conventional practice to give good levelling, exhaustion and fastness properties. This results in benefits in terms of less fibre damage, less yellowing and savings in time and energy consumption, compared with traditional methods. A further objective of this invention is to produce dyeings that are less skittery than those produced by alternative procedures. (Note: "skittery" is a term used to denote an uneven distribution of dye along a fibre.)
Anionic, cationic and amphoteric surfactants are used widely in the textile industry, as assistants for dyeing wool and other fibres by exhaustion methods. It is well known that the rate of exhaustion of dyes onto wool is enhanced by addition of certain surfactants to acidic dye liquors (see, for example, Hine, R. J. and McPhee, J. R., Rapid Dyeing of Wool Without Damage, Dyer, 132, p.523 (1964). The compounds that are most commonly used for this purpose are nonionic or amphoteric in nature; their addition to acidic dye liquors gives improvements in the rate of exhaustion and penetration into the fibre of many dyes. They also produce improvements in the appearance of the resultant dyeings, in terms of decreased skitteriness. These effects are utilised in low temperature dyeing procedures, in which wool is dyed at temperatures below the boil (usually 75.degree.-90.degree. C.).
SUMMARY OF THE INVENTION
The present invention is based on the unexpected observation that aqueous pretreatment of keratin fibres, such as wool, with an amphoteric surfactant, preferably under alkaline conditions, prior to addition of dyes, increases the rate of exhaustion, rate of penetration and overall uniformity of dyes applied from acidic dyebaths. The increased rate of penetration enables dyeings of excellent fastness properties and colour yield to be obtained at lower temperatures and/or in shorter times, compared with conventional practice. A feature of the present invention is that a differential dyeing effect is obtained when the pretreated wool is dyed in the same dyebath as untreated material. Treatment with an alkaline solution of an amphoteric surfactant, according to the method described herein, has also been found to provide an effective pretreatment for the application of dyes in the form of conventional print pastes to wool substrates. Thus, the surfactant/alkali treatement can be used instead of the chlorination procedures commonly employed in industry. Furthermore, it has been found that the pretreatment can be applied to wool in the form of a paste containing the amphoteric surfactant, an alkali and thickening agent. The printed fabric is stored for a time between 1 min and 24 hr, precautions being taken to prevent the printed area from drying-out. After the chemicals have been washed from the fabric, the latter can be dyed immediately or dried and dyed later. When the fabric is dyed, a "tone-on-tone" effect is produced, with the printed regions dyed to a deeper shad than the base fabric.
The invention accordingly provide
REFERENCES:
patent: 3619106 (1971-11-01), L'Oreal
patent: 4063877 (1977-12-01), Elliot et al.
patent: 4293543 (1981-10-01), Cotte et al.
patent: 4425132 (1984-01-01), Grollier et al.
patent: 4615709 (1986-10-01), Nakao
patent: 4663158 (1987-05-01), Wolfram
patent: 5173085 (1992-12-01), Brown et al.
patent: 5192333 (1993-03-01), Lapidus
Rapid Dyeing of Wool Without Damage, Hine et al., 1964.
Supplementary European Search Report 88 90 3132, Jun. 27, 1991, The Hague.
Journal of the Society of Dyers & Colourists, The Influence of Amphoteric Products on the Affinity of Wool for Acid dyes, vol. 103, Jan. 1987.
F.J. Harrigan & J.A. Rippon, "A New Method For Dyeing Wool At Low Temperature" Textile Institute 1988 World Conference (pp. 412-419).
J. Riva and J. Cegarra, The influence of amphoteric prodcuts on the affinity of wool for acid dyes Journal of the Society of Dyers & Colourists (1987) Jan. No. 1 pp. 34-37 Bradford Gr. Britain.
Commonwealth Scientific and Industrial Research Organization
Johnson Jerry D.
LandOfFree
Process for dyeing wool and other keratin fibres does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Process for dyeing wool and other keratin fibres, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Process for dyeing wool and other keratin fibres will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1111026