US4654309A — Test method and article for estimating the concen…

Claim 1

Independent Claim 180 words

An article for determining the concentration of free fatty acid in a liquid such as cooking oil, motor oil, and the like, said article comprising a substantially non-reactive, neutral, porous and oil absorbent, support material having at least one defined test area capable of absorbing a known volume of said liquid, said test area being impregnated with (a) a predetermined amount of base compound reactive with acid absorbed in said test area of said support and being present in said test area in an amount equivalent to a known amount of free fatty acid; (b) an effective amount of acid-base indicator capable of changing color, when the predetermined amount of base has reacted with the known amount of free fatty acid, in a pH range on the order of 6-10; and (c) about 30-99.5 parts by weight based upon the total weight of the non-volatile constituents of (a), (b) and (c) of a substantially colorless, substantially neutral, humectant dihydroxy aliphatic polyethylene glycol organic solvent which has a molecular weight less than about 2000 and is substantially non-volatile under ambient conditions.

Claim 2

Dependent Claim 180 words

An article for determining the concentration of free fatty acid in a liquid such as cooking oil, motor oil, and the like, said article comprising a substantially non-reactive, neutral, porous and oil absorbent, support material having at least one defined test area capable of absorbing a known volume of said liquid, said test area being impregnated with (a) a predetermined amount of base compound reactive with acid absorbed in said test area of said support and being present in said test area in an amount equivalent to a known amount of free fatty acid; (b) an effective amount of acid-base indicator capable of changing color, when the predetermined amount of base has reacted with the known amount of free fatty acid, in a pH range on the order of 6-10; and (c) about 30-99.5 parts by weight based upon the total weight of the non-volatile constituents of (a), (b) and (c) of a substantially colorless, substantially neutral, humectant dihydroxy aliphatic polyethylene glycol organic solvent which has a molecular weight less than about 2000 and is substantially non-volatile under ambient conditions.

Claim 3

Dependent Claim 13 words

The article of claim 1 wherein said support material is formed of paper.

Claim 4

Dependent Claim 31 words

The article of claim 1 wherein said base compound is selected from the group consisting of sodium carbonate, sodium bicarbonate, potassium carbonate, potassium bicarbonate, tetramethyl guanidine, guanidine carbonate and amino silane.

Claim 5

Dependent Claim 26 words

The article of claim 1 wherein said indicator is selected from the group consisting of m-cresol purple, neutral red, Thymol blue, phenol red and cresol red.

Claim 6

Dependent Claim 48 words

The article of claim 1 wherein said support material has a plurality of test areas, each containing said composition but with varying predetermined amounts of said base compound in each of said test areas to provide amounts equivalent to a range of known amounts of free fatty acid.

Claim 7

Dependent Claim 29 words

The article of claim 5 wherein said test areas are separated by barrier stripes which prevent the migration of ingredients from one test area to an adjacent test area.

Claim 8

Dependent Claim 36 words

The article of claim 5 wherein said test areas are spacially separated and adhered to a carrier strip formed of a barrier material which prevents migration of ingredients from one of said test areas to another.

Claim 9

Independent Claim 181 words

A method of determining the concentration of free fatty acid in a liquid comprising (a) absorbing a predetermined volume of the liquid to be tested in a test area of a test article comprising a substantially non-reactive, neutral, porous, oil absorbent and nonbuffering support material having at least one test area impregnated with a composition comprising (1) a predetermined amount of base compound reactive with free acid and being present in an amount equivalent to a known amount of free fatty acid absorbed in said test area; (2) an effective amount of acid-base indicator capable of changing color, when the predetermined amount of base has reacted with the known amount of free fatty acid, in a pH range on the order of 6-10; (3) about 30-99.5 parts by weight based upon the non-volatile constituents of the total weight of (1), (2) and (3) of a substantially colorless, substantially neutral, humectant dihydroxy aliphatic polyethylene glyco organic solvent which has a molecular weight less than about 2000 and is substantially non-volatile under ambient conditions; and (b) observing any color change in said article.

Claim 10

Independent Claim 181 words

A method of determining the concentration of free fatty acid in a liquid comprising (a) absorbing a predetermined volume of the liquid to be tested in a test area of a test article comprising a substantially non-reactive, neutral, porous, oil absorbent and nonbuffering support material having at least one test area impregnated with a composition comprising (1) a predetermined amount of base compound reactive with free acid and being present in an amount equivalent to a known amount of free fatty acid absorbed in said test area; (2) an effective amount of acid-base indicator capable of changing color, when the predetermined amount of base has reacted with the known amount of free fatty acid, in a pH range on the order of 6-10; (3) about 30-99.5 parts by weight based upon the non-volatile constituents of the total weight of (1), (2) and (3) of a substantially colorless, substantially neutral, humectant dihydroxy aliphatic polyethylene glyco organic solvent which has a molecular weight less than about 2000 and is substantially non-volatile under ambient conditions; and (b) observing any color change in said article.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1990-03-30	1990-09-29	1991-03-31	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1994-03-30	1994-09-29	1995-03-31	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	1998-03-30	1998-09-29	1999-03-31	$7700.00	Window Closed / Lapsed

Test method and article for estimating the concentration of free acid in liquid

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