Recipe A(one-bath process)

Scouring agent

2g/l

Penetrant

2g/l

Stabilizer

2g/l

Caustic soda(100%)

6g/l

H2O2

12g/l

Whitening agent VBA

0.3% O.W.F

(Bath ratio:1:15; boil out the goods being whitened at 95-98°C for 60 minutes, then rinse and dry it.)

Recipe B(used together with resin in padding bath)

Resin 2D

64g/l

Whitening agent VBA

3g/l

Citric acid(10%)

5ml/l

Penetrant and softener

some

Catalyst

6g/l

-

-

(Exhaust twice and pad twice;adjust the PH value to 5-6; dry the whitened goods at 80-100°C,cure it at 140-180°C,then open-wash it for 20-30 seconds and dry it again.)

Item

Indices

Appearance

light yellow even-sized powder

E Value

100% of the standard agent

Hue

slightly different from the standard agent

WCIE (whiteness different between VBA and the standard agent)

≥-3.0

Moisture content

≤5%

Content of insoluble impurities

≤0.5%

Fineness(quantity of residue on sieve having 180um meshes)

≤10%