Change to read:
Labeling
Label it to indicate that it is not intended for internal use.
A carbomer homopolymer manufactured using benzene and complying with the unique requirements of this monograph will be officially titled Carbomer 941 and will not be referred to as
Carbomer Homopolymer.
NF24
Viscosity
Proceed as directed in the test for
Viscosity under
Carbomer 934P, except to use a spindle having a disk 2.11 cm in diameter and 0.16 cm high attached to a shaft 0.32 cm in diameter, the distance from the top of the disk to the lower tip of the shaft being 2.7 cm, and the immersion depth being 4.92 cm (No. 5 spindle). The viscosity is between 4000 and 11,000 centipoises.
Limit of benzene
Proceed as directed in the test for
Limit of benzene under
Carbomer 934P, except to use about 20 mg of Carbomer 941, accurately weighed, instead of about 1 g of Carbomer 934P, to prepare the
Test solution. Calculate the percentage of benzene in the portion of Carbomer 941 taken by the formula:
10(C/W)(rU / rS)
in which
C is the concentration, in µg per mL, of benzene in the
Standard solution; W is the weight, in mg, of Carbomer 941 taken to prepare the
Test solution; and
rU and
rS are the benzene peak responses obtained from the
Test solution and the
Standard solution, respectively: not more than 0.5% is found.