Cotton Color Grading

Color Grade of Cotton

The color grade (CG) of the cotton is based on a quadrant chart of cotton color. The diagram of the color chart has both +b and Rd intersects. For example, the Cotton sample has a Rd value of 71.7 and a +b value has 9.6, its color grade (CG) will be 42-1. The higher the number verse the cotton color. Also, it includes color grades for traditional classers or graders for cotton as white, light spotted, spotted, tinged, and yellow stained cotton.

Several factors impact the color of cotton fiber. The environmental factors affect the large as rainfall, temperature, microorganisms, and variety of cotton. Also, other factors like soil nutrients, leafy portion during harvesting, storage, moisture level, and ginning of cotton determine the shade of cotton fibers.

Nickerson /Hunter Cotton colorimeter diagram

The color of cotton is measured by using the Nikerson /Hunter Cotton colorimeter diagram. There are 25 color-grade categories with five additional ones to represent low-grade cotton for American upland cotton developed by USDA (United States Department of Agriculture).

HVI Color Grade

HVI Uster measures the most important cotton fiber property, as designed for this purpose. These properties are highly needed in spinning yarn color consistency in afterward processing.

Reflectance Rd

Reflectance Rd represents the whiteness of cotton, that light reflects from cotton fiber. Rd value represents the Nikerson/Hunter color chart with a conjection of (+b) yellowness value to determine the color grade of cotton fiber.

Yellowness +b

+b represents the yellowness of cotton by the reflectance of light. Its value is determined by using a yellow filter. +b value represents the Nikerson/Hunter color chart with the connection of (+b) yellowness value to determine the color grade of cotton fiber.

Universal grading standard of cotton

The United States Department of Agriculture (U.S.D.A) has mentioned universal grades of cotton. But these grades are only for saw-ginned upland cotton accepted in the world.

1. Midding fair (M.F.)
2. strict good middling (S.G.M.)
3. Good middling (G.M.)
4. Strict middling (S.M.)
5. Middling (M)
6. strict low middling (S.L.M.)
7. Low middling (L.M.)
8. Strict good ordinary (S.G.O.)
9. good ordinary (G.O.)

These 9 grades are universal. for grading, there is a universal grading/classing box. Grade number 5 is the basis for grading.

Acceptance of U.S.D.A

Although these grades are accepted in the world, many countries do not accept them due to the following reasons.

1. These are only for saw-ginned cotton countries while roller-ginning-producing cotton can’t accept these standards.
2. These standards are for American upland cotton which is creamy but can’t accept in other saw ginned like Pakistan and India where cotton color is more white and Egyptian cotton is more creamy. So these color grades can’t fulfill the physical color range.
3. Thirdly these grades are not applicable for long-staple cotton i-e Egyptian cotton.
4. Lastly, there is no consideration of maturity and strength in these grades.

In conclusion, the cotton standard can’t be used throughout the world as every country has its own standard.

1. In the United States U.S.D.A (united state department of agriculture)
2. In Pakistan K.C.A (Karachi Cotton Association)
3. In Idia CAI (Cotton Association of India)
4. In Egypt C.E.A (Cotton Egypt Association)
5. In China C.C.A (China Cotton Association)

So we can say every country has its commercial standards.