Heat Color Fastness:
Heat color fastness refers to the ability to keep original color of dyed fabrics under conditions of different heat. Heat color fastness test can be done in dry, tide, wet environment, which depends on the use of textiles. The machine using in heat color fastness test is Ironing Sublimation Color Fastness Tester. When testing, dyed sample pasting with one or two prescribed adjacent fabric contact closely with heating device, heated in a certain time under specified temperature and pressure.
Dry pressing means dry sample is pressed in heating device with prescribed temperature and pressure in a certain time; tide pressing means dry sample is pressed in heating device with prescribed temperature and pressure in a certain time after it is covered by a wet cotton adjacent fabric; wet pressing means wet sample is pressed in heating device with prescribed temperature and pressure in a certain time after it is covered by a wet cotton adjacent fabric. Discoloration of sample and staining of adjacent fabric are measured by gray cards.
Heat Color Fastness Test:
Preparation of Test Apparatus and Materials
Ironing Sublimation Color Fastness Tester (Figure 4), Multi-fiber Adjacent Fiber or Standard Single Fiber Adjacent Fabric, Sample to be Tested.
Testing Method:
a) Sample Preparation
If tested sample is fabric, take a sample of 40mm*100mm. If tested sample is yarn, weave it as a fabric and take a sample of 40mm*100mm; or yarn is winded closely on a hot inert material of 40mm*100mm to form a thin layer which is just equal to yarn thickness. If sample is scattered fiber, take enough amount and comb into a thin layer of 40mm*100mm, then sewing on a cotton adjacent fabric.
b) Operating Procedure
Combined sample is laid between two metal heating plates controlled precisely by heating system, heated under moderate temperature and pressure. The press temperature depends on fiber types and organizational structure of fabrics and garments. We usually use three types of temperature: 110℃±2℃, 150℃±2℃, 200℃±2℃. If necessary, you can adopt other temperature. If sample is blended fabric, the used temperature should conform to least heat-resistant fibers.
The tested sample which has been made heating and dry treatment must adjust its moisture in standard atmosphere before testing.
Asbestos board, wool Flannel, dry unstained cotton should be covered all the time, no matter whether the down heating plate of heating device is heating.
The fabric is subjected to hot pressing as required.
Dry pressing: dry sample is placed on the cotton cloth covered by wool flannel liner; put the up heating plate down, to hot press it for 15s in specified temperature.
Tide pressing: dry sample is placed on the cotton cloth covered by wool flannel liner; Take a cotton adjacent fabric of 40mm*100mm, soak it in water, and make its water content equal to its quality through squeezing or throwing, then put the wet fabric on the dry sample; put the up heating plate down, to hot press it for 15s in specified temperature.
Wet pressing: the tested sample is soaked together with a cotton adjacent fabric of 40mm*100mm in water, and make its water content equal to its quality through squeezing or throwing, then put it on the cotton cloth covered by wool flannel liner; put the up heating plate down, to hot press it for 15s in specified temperature.
Take the tested sample out, use gray cards to evaluate discoloration of original sample and staining degree of white cloth. Then put it in standard atmosphere (means temperature is 20℃±2℃, relative humidity is 65%±2%) for 4 hours, then evaluate it again.
