1. Graying and yellowing of fabrics
Common graying phenomena usually occur due to the following reasons.
a. The detergent or washing procedure is defective, causing the dirt that separated from the fabrics during washing to attach to the linens again in the washing liquid.
b. Minerals contained in poor water quality are retained on linens.
c. Excessive use of softener makes the fabric water-repellent and difficult to remove stains, resulting in graying.
Common yellowing usually occurs due to high levels of iron ions in the wash water supply. Depending on the level of iron present, corrective measures may include using iron-removing water treatment equipment or increasing the amount of water treatment agents and acids used in the wash process.
Sometimes you can see “zebra striping” in linen (a stack of clean folded fabrics is found to have light and dark phenomena). This is a prelude to ordinary fading and reflects imperfect inventory turnover. , one part of the linen is used more frequently, while another part of the linen is used less frequently. In addition, some other conditions will also cause obvious uneven light and dark phenomena in linen, such as different quality of linen and different purchase time.
2. Reasons for fabric damage
The damaged fabric must be carefully inspected to determine the cause of the damage.
(1) Physical damage Physically damaged linens often have clear pull marks, either straight or at an angle (usually 90°) , if the fabric strength of the damaged area is not significantly different from the strength of other parts of the fabric, it is most likely caused by physical damage.
Determining the comparative strength of the fabric can be done by tearing at the damaged part and tearing at other parts of the fabric. If the strength of the two different parts is the same, it proves that the damage is not caused by chemical reasons. of.
(2) Chemical damage
If chemical damage occurs, it usually results in deterioration ranging from small holes to irregular shapes. Chemical damage to 100% cotton products is usually small pinholes or slightly larger irregular holes. When damage occurs to a certain area, extensive loss of fabric tension will occur. The damaged parts of the fabric will become thinner and easier to tear, while the strength of the surrounding parts will remain unchanged. When a large area is damaged, the velvet stripping phenomenon will be serious and the service life of the linen will be shortened. Polyester/cotton blended fabrics will show chemical damage in an extremely thin form instead of holes. The cotton fibers are destroyed and washed away, while the more resistant polyester fibers are preserved. The damaged area will feel thin and almost transparent. Ordinary damage will cause the entire fabric to become extremely thin, transparent and wrinkle-prone. Because the natural aging process of cotton fiber shedding is similar to ordinary chemical damage, the two are sometimes easily confused.
3. Analysis of causes of physical damage
If the damage indicates physical damage, the linen is likely to If you come into contact with sharp metal corners during the washing process, don’t think that this always happens in the laundry room. It is more likely that this physical damage occurs elsewhere.
If several similar linens show the same nature and location of damage, further clues can be considered. For example, if several sheets are damaged in the same area, you should look for sharp metal corners on the bed frame; loose metal parts where the sheets come into contact with them; or exposed sharp corners on the metal storage racks. If there are no signs of fixed physical damage to the entire area on the fabric, the cause may be diverse, including sharp metal edges in the laundry tube, laundry basket, or even the drum of the washing machine.
If extensive burrs appear on the fabric, this may be caused by friction or excessive tumbling of the linen in the washing tub, the water level is too low, or the drying time in the dryer is too long.
If you find tears in the linen, you should carefully check the wheels of the washing machine or dryer. If there are sharp edges or burrs on these wheels, they will cause tears in the fabric. A simple way to check these runner is to use a nylon tube to rub all over the inner surface of the runner. Suspicious sharp edges or burrs will be easily found. After discovery, the sharp edges or burrs need to be smoothed with a file or grinding wheel.
