Résumé : |
For various reasons the aniline dyeing of leather has increased appreciably in recent years. There is a definite trend toward a more natural look and pleasant handle, not only for upholstery and clothing leather, but also for shoe upper leather. As a result, heavily pigmented finishes are being used less, and more and more importance is being placed on drum dyeing and occasionally spray dyeing. Following this trend, competent dyestuff producers have not only expanded their range of dyestuffs to include those with greater fastness, but they have also developed specific auxiilary agents to improve penetration, leveling, and dye fixation. Furthermore, research has been done to improve the buildup of dyes that influence dyeing behavior. We, too, have worked in these areas, and some of the results we have obtained are presented in this report.
Very early in our studies, we gave special consideration to two properties of dyes which are actually independent of each other : buildup and exhaustion. Of the two, according to our experience, buildup capacity is by far the more important. |