The apparel that we wear is more than simply about style, color, and
fit. The clothing that we wear must be trendy & comfortable, but it
also must be made of proper quality. Nothing is worse than
purchasing clothing in the perfect color, only to find that after you
washed it the color changes. Do you know why the fabric color
changed? Do you know why it is best to wash your whites and darks
separately? Dye from one garment on occasion will transfer from one
cloth to another. The information below is intended to help
explain what is happening.
Crocking
Bleeding
Colorfastness
What is the difference between crocking and bleeding?
Crocking
occurs
when excess dye rubs off of one dry fabric onto another dry
fabric. Crocking is usually more of a problem with dark and vivid
colors. Note: during testing, colorfastness can be tested on wet
and dry fabric.
Bleeding
is a similar problem to crocking, but occurs when dyes transfer from one
fabric to another when fabrics are wet.
Crocking occurs when the dye is physically rubbed off.
Bleeding is when dye comes of the fabric when dye comes into contact
with liquid.
Examples:
If you put a red t-shirt in the laundry with white underwear and the
white underwear turns pink. You have experienced the fabric
bleeding (dye came in contact with water, loosened off the shirt and
moved onto the underwear from the red dye being in the water).
If you are wearing a long red t-shirt and white pants. You that
remove your shirt and notice red stains on your pants what they came in
contact with your shirt, you have experienced fabric crocking (two
fabric rubbed together causing problem).
Wet Crocking or Dry Crocking
Transfer of dye from the surface of a dyed or printed fabric onto
another surface by rubbing. The more color is transferred, the
more the fabric "crocks". Crocking determines the amount of color
transferred from the surface of colored textile material to other
surfaces by rubbing.
Dye crocking is the result of color loss by mechanical actions such as
friction and abrasion. Crocking can be the result of lack of
penetration of the dyeing agent, the use of incorrect dyes or dyeing
procedures, or the lack of proper washing procedures and finishing
treatments after the dyeing process. If the textile dying or
printing process is not done properly, the rubbing-off of dye from a
fabric may occur.
Crocking often occurs in heavily dyed fabric, such as raw denim.
Crocking is one of the processes that helps give raw denim its
personality and is the cause for fades and atari on creases, seams, and
any other worn areas.
Technically, crocking can occur under dry or wet conditions.
Colorfastness
Clothing is colorfast if its colors and dyes do not bleed or run from
the clothing. Colorfastness is often tested by clothing
manufacturers.
Color fastness is a term used in the dyeing of textile materials,
meaning resistance of the material's color to fading or running. The
term is usually used in the context of clothes. The first known use of
the word colorfast was in 1916.
Bleeding
The running of color form wet dyed material onto a material next to it
or the running of colors together.
Fabric bleeding occurs when damp fabrics lose their dyes; you'll likely
notice that bleeding colors have stained the wash water. Although
bleeding is most commonly seen when washing vividly colored fabrics,
particularly reds and purples, it can occur with other colors of fabrics
as well.
The undesirable loss of dye when the textile is immersed in water or
across into an adjacent area or when in contact with another substrate.
Testing
There are many different colorfast tests.
Colorfastness is a fabric's ability to retain color in various
conditions. Tests are performed that involve wet and dry crocking.
Crocking refers to the rubbing off of color from a fabric when subjected
to abrasion.
One test is the AATCC 8-2001. This "is a test method of the
American Association of Textile Chemists and Colorists (AATCC). This
method uses a standard white cotton fabric that is rubbed against the
surface of the test fabric. To test for wet crocking the standard fabric
is wet before rubbing against the test fabric. After rubbing under
controlled pressure for a specific number of times the amount of color
transferred to the white test squares is compared to an AATCC color
chart and a rating is established."
Grade 5 = no color transfer Grade 1 = high degree of color transfer
Another test is the AATCC 116-2001. This "is a test method of the
American Association of Textile Chemists and Colorists (AATCC). This
test is specifically used for printed fabrics that do not lend
themselves to the AATCC 8-2001 method. The test fabric is held at the
base of a Rotary Vertical Crockmeter and rubbed with a standard cotton
white fabric either dry or wet. After rubbing under controlled pressure
for a specific number of times the amount of color transferred to the
white test squares is compared to an AATCC color chart and a rating is
established."
Grade 5 = no color transfer
Grade 1 = high degree of color transfer
Here is an example of what sort of test you can find at the AATCC
website:
One example, AATCC Test Method 8-2013 Test Colorfastness to
Crocking: AATCC Crockmeter Method
You can find many more options at the following page:
Above we have listed testing examples. The official tests may have
changed since the time we have posted this information. We
strongly recommend that you consult directly with a certified testing
lab to obtain the most current requirements and fabric testing methods.
Learn more about
fabric testing methods here on Apparel Search.
You might also want to learn about tensile strength which is relevant to testing fabric, fiber & yarn.
Thank you for using the Apparel Search website.