fluorescent whitening agent

Tinopal OB CO fluorescent optical brightener that shows

•  brilliant bluish whitening effects
•  excellent heat resistance
•  high chemical stability
•  good compatibility in a wide range of resins

chemical nature            2,5-thiophenediylbis(5-tert-butyl-1,3-benzoxazole

CAS number                 7128-64-5

molecular weight           430.6 g/mol


physical form               yellow powder

typical properties        density at 20 °C (68 °F)  ~ 1.26 g/cm³


solubility at 20 °C (68 °F)

acetone                                      0.5 g/100 g solution
chloroform                                 14 g/100 g solution
dimethyl formamide                  0.8 g/100 g solution
dioxane                                         2 g/100 g solution
n-hexane                                    0.2 g/100 g solution
methanol                                    0.1 g/100 g solution
methylethyl ketone                    1.3 g/100 g solution
tricresyl phosphate                   0.8 g/100 g solution
xylene                                            5 g/100 g solution
water                                      0.001 g/100 g solution


Tinopal OB CO is recommended for applications such as

•  white and pastel-tone paints where it intensifies the degree of
•  clear coats and overprint varnishes where it is used to mask the
yellowish inherent color and also to intensify the brilliance of white
and colored base coats
•  primer and/or topcoats where it is used as a marker to identify
voids, holidays and uneven coverage
•  black and blue printing inks to increase their deep tone
•  printing inks for quick identification, security and safeguard against
forgeries (i.e., bank notes)
•  packaging inks as promotional tool or as tracer for packaging lines
•  manufacture of fluorescent pigments/dyestuffs to reinforce the
brightness of certain shades, particularly blue ones
•  thermal dye diffusion paper to enhance paper whiteness
•  film base for photographic paper