What is Sanfor?
The Sanforized trademark was first registered in the United States of America in 1930. Today the trademark is registered in over 100 countries worldwide. Our extensive network of global licensees uses the trademark on both 100% cotton and cotton-blend fabrics which meet special test requirements and conform to a precise standard of shrinkage established by The Sanforized Company.
Manufacturers of garments made of these fabrics may label their merchandise Sanforized. Thus the retailer and the ultimate consumer can tell at a glance that the fabric in a garment so labeled will not shrink out of fit.
This is uniformly true everywhere in the world, wherever cotton and cotton-blend merchandise is produced and sold, because the same processing, testing and inspection procedures are carried out with each and every licensee.
Sanforized technical service representatives perform constant inspection and check-testing at the plants of textile mills licensed to produce "Sanforized" fabrics. This insures that a uniform standard is maintained.
The Sanforized trademarks are known at both trade and consumer levels worldwide because of their universal assurance of quality. Textile users — manufacturers, retailers, and consumers — have confidence in Sanforized. They ask for it. They have been asking for it for more than 70 years.
The Sanforized license program is unique and without parallel in the textile and apparel industries. Our leadership and expertise in quality shrinkage control are well-known in every major textile market of the world.
What causes shrinkage?
During spinning, weaving, bleaching, dyeing and the various finishing processes, yarns and cloth are under a continuous tension.
Yarns and/or fabrics are not fixed materials. They consist of separate, stretchable fibers which submit to the tension. In other words, fabrics do stretch in length and width. The tension within the yarns, which is caused by this stretching, can be eliminated when the friction within the fabric is reduced. This reduction in friction occurs during laundering where both water and soap act as a lubricant. The lubricant, along with the mechanical action of the washer, helps the fibers relax and contract to their original length before the elongation takes place. This means that the fabric shrinks and recaptures its original equilibrium.
Controlled Compressive Shrinkage Process
The internationally well-known and most important shrinking process today dates back more than 80 years. Though the correct expression for this process is Controlled Compressive Shrinkage. SANFOR / SANFORIZED are Registered Trademarks. The process is a purely mechanical treatment without any addition of chemicals.
The word SANFORIZED / SANFOR is derived from the first name of the inventor of the compressive shrinkage process, Mr. Sanford L. Cluett.
The Sanforized label means dimensional stability for garments made up of Sanforized labeled fabrics.
The purpose of the process is to shrink fabrics in such a way that textiles made up of these fabrics do not shrink during washing.
The amount of potential wash shrinkage must be determined prior to shrinking. A full width sample is wash-tested according to the test method. After the lengthwise and widthwise shrinkage has been determined, the compressive shrinkage machine can be adjusted accordingly.
The process can be described by the following schematic:
Fabric (F) passes through the skyer (S) or other moistening device and is moistened by water and/or steam. This will lubricate the fibers and promote shrinkability within the fabric. Normally, a fabric must be moistened in such a way that every single thread achieves a moisture content of approximately 15%. This allows compression of the fabric with very little resistance.
When the fabric passes through the clip expander (C), we obtain the required width. The clip expander also transports the fabric to the most important part of the machine: the rubber belt unit (indicated by arrows in above figure). In the close-up of fig. 1, we see the endless rubber belt (R). By squeezing rubber belt (R) between pressure roll (P) and rubber belt cylinder (RB), we obtain an elastical stretching of the rubber belt surface. The more we squeeze the rubber belt, the more the surface is stretched. This point of squeezing is known as the pressure zone, or the nip point.
Fabric (F) is now fed into the pressure zone. When leaving the pressure zone, the rubber belt recovers itself and the surface returns to its original length carrying the fabric with it. The effect of this action is a shorting of the warp yarn which packs the filling yarns closer together. At this actual moment, shrinkage occurs.
After compaction within the rubber belt unit, the fabric enters the dryer (D). Here the fibers are locked in their shrunken state by removing the moisture from the fabric.
After the compressive shrinkage process is completed, another sample of the fabric is taken. This sample is also wash-tested. The final result of this test must meet the Sanforized Standard, in length and width before it may carry the Sanforized label.
All Sanforized Licensees are contractually obligated to follow the required test method and meet the standards set forth by SANFOR GmbH.