Appeal No. 2000-0022
Application No. 08/888,173
13. A composition for inhibiting barium scale
formation in water comprising an aqueous solution having a
phosphonate dissolved therein in a quantity effective to
inhibit barium scale formation, said phosphonate having the
formula:
wherein Z= -CHR1PO3R2
R = H, CH3, C2H5 or M
R1 = H, CH3, CR3, C6H5, SO3H2
M = alkali metal or ammonium ion
n is a number in the range 2 to 4,
m is a number in the range 2 to 4,
a is a number in the range 2 to 6,
b is a number in the range 2 to 10,
x is a number in the range 0 to 6, and
y is a number in the range 1 to 6
provided that at least one of n, b or m is greater than 2.
18. A composition according to claim 15 wherein n is
3, m is 3, b is 2, x is zero and y is 1.
19. The composition of claim 13, wherein a is a
number in the range 2 to 4 and b is a number in the range 2
to 4.
The reference relied upon the examiner as evidence of
unpatentably is:
Kautsky 3,738,937 June 12, 1973
Claims 13-19 stand rejected under 35 U.S.C. § 103 as being
unpatentable over Kautsky.
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