Denim Dry Finishing Overview
Many dry finishing techniques for denim can be combined with wet processes, either before or after wet finishing, to produce unique looks and performance. Most dry finishing techniques are aimed at removing the outer layer of the indigo-dyed yarn to reveal the white core beneath the surface. As with wet finishing, the character of the yarn itself is the key to effective use of dry finishing processes.
For many years, the most popular look for denim jeans has been the distressed, antiqued, or damaged look achieved by localized sanding. Sanding can be done with an industrial sandblaster, with power tools, or by hand with sandpaper. The goal is to create varying levels of abrasion throughout the garment. Typically, more abrasion is applied to those areas that would normally show wear or fray over many wearings.
Brushing is a surface abrasion technique that uses wire- or bristle-covered brushes to give denim an antiqued appearance. The brushes operate at high speed, powered by air or an electric motor. The abrasion produced by the brushes ranges from subtle to severe. Brushing is faster than hand sanding and is usually less destructive.
In recent years, laser technology has been adapted to denim finishing to create effects that mimic whiskers and sanded areas and even to create holes. In laser finishing, a condensed beam of light is focused on the surface of the fabric to burn off the top layer of dyestuff. Because laser systems are controlled by CAD/CAM technology, almost any distressed effect can be achieved quickly and consistently.
For more information on laser technology, explore Cotton Incorporated’s technical bulletin on the topic: Laser Applications on Cotton Textiles.
Whiskers and creases are extremely popular denim garment finishing effects that mimic the abrasion and wear lines normally developed over many wearing cycles. These abrasion and wear lines most often occur horizontally along the lap area, the front of the thighs, the back of the knees, and the bottom of the pant legs. Denim garment finishers have developed effective methods to reproduce these aged effects on new garments. Resin finishing is combined with the use of pressing and abrading tools and techniques to create authentic-looking wrinkles, lines, and creases.
Some denim aficionados prefer special effects that replicate the look of harsh, even extreme wear and use. These effects can be achieved by scraping, cutting, and making holes — all of which can be done in the denim garment finishing plant. Some of the devices used to create holes and slashes include scalpels, razor blades, and puncturing devices, using templates that resemble nail or screw boards. Often, homemade devices are used to create a specific effect. Other special effects include tacking, embroidery, and appliqués.