US3954840A — 1,3,5,7-Naphthalenetetracarboxylic acids and proc…

Claim 1

Independent Claim 36 words

A compound of the formula ##SPC9## wherein the X's may be the same or different and are selected from the group consisting of hydrogen atoms, alkali metals, alkyl having 1 to 12 carbon atoms and allyl.

Claim 2

Dependent Claim 36 words

A compound of the formula ##SPC9## wherein the X's may be the same or different and are selected from the group consisting of hydrogen atoms, alkali metals, alkyl having 1 to 12 carbon atoms and allyl.

Claim 3

Dependent Claim 9 words

The compound of claim 1 which is 1,3,5,7-naphthalenetetracarboxylic acid.

Claim 4

Dependent Claim 9 words

The compound of claim 1 which is tetrapotassium 1,3,5,7-naphthalenetetracarboxylate.

Claim 5

Dependent Claim 9 words

The compound of claim 1 which is tetrasodium 1,3,5,7-naphthalenetetracarboxylate.

Claim 6

Dependent Claim 9 words

The compound of claim 1 which is tetramethyl 1,3,5,7-naphthalenetetracarboxylate.

Claim 7

Dependent Claim 9 words

The compound of claim 1 which is tetra-n-butyl 1,3,5,7-naphthalenetetracarboxylate.

Claim 8

Dependent Claim 9 words

The compound of claim 1 which is tetra-n-dodecyl 1,3,5,7-naphthalenetetracarboxylate.

Claim 9

Dependent Claim 20 words

The compound of claim 1 which is 3,7-dialkali metal 1,3,5,7-naphthalenetetracarboxylate of the formula ##SPC10## wherein M is an alkali metal.

Claim 10

Dependent Claim 13 words

The compound of claim 8 wherein said dialkali metal salt is 3,7-dipotassium 1,3,5,7-naphthalenetetracarboxylate.

Claim 11

Dependent Claim 13 words

The compound of claim 8 wherein said dialkali metal salt is 3,7-disodium 1,3,5,7-naphthalenetetracarboxylate.

Claim 12

Dependent Claim 133 words

A process for preparing an alkali metal 1,3,5,7-naphthalenetetracarboxylate of the formula ##SPC11## wherein M is an alkali metal, which comprises heating a mixture of at least one alkali metal naphthalenecarboxylate of the formula ##SPC12## wherein n is an integer of 1 to 4; and M is an alkali metal with the proviso that when n is 4, the four --COOM groups are not present simultaneously at the 1,3,5,7-positions, and 1-40% by weight, based on the weight of the mixture, of said alkali metal 1,3,5,7-naphthalenetatracarboxylate to a temperature of at least 350°C. in an atmosphere of an inert gas and in the presence of a catalyst selected from the group consisting of the halides, oxides, sulfates, carbonates and carboxylates of zinc or cadmium and recovering the resulting alkali metal 1,3,5,7-naphthalenetetracarboxylate from the reaction mixture.

Claim 13

Dependent Claim 133 words

A process for preparing an alkali metal 1,3,5,7-naphthalenetetracarboxylate of the formula ##SPC11## wherein M is an alkali metal, which comprises heating a mixture of at least one alkali metal naphthalenecarboxylate of the formula ##SPC12## wherein n is an integer of 1 to 4; and M is an alkali metal with the proviso that when n is 4, the four --COOM groups are not present simultaneously at the 1,3,5,7-positions, and 1-40% by weight, based on the weight of the mixture, of said alkali metal 1,3,5,7-naphthalenetatracarboxylate to a temperature of at least 350°C. in an atmosphere of an inert gas and in the presence of a catalyst selected from the group consisting of the halides, oxides, sulfates, carbonates and carboxylates of zinc or cadmium and recovering the resulting alkali metal 1,3,5,7-naphthalenetetracarboxylate from the reaction mixture.

Claim 14

Dependent Claim 124 words

A process for preparing an alkali metal 1,3,5,7-naphthalenetetracarboxylate of high purity, which comprises heating at least one alkali metal naphthalenecarboxylate of the formula ##SPC13## wherein n is an integer of 1 to 4; and M is an alkali metal with the proviso that when n is 4, the four --COOM groups are not present simultaneously in the 1,3,5,7-positions, to a temperature of at least 350°C. in an atmosphere of an inert gas, dissolving the reaction mixture obtained in water, adjusing the alkali ion concentration of the resulting aqueous solution to at least 6 g-alkali ion/ 1000 g-water, hot filtering the solid substance precipitated, then precipitating an alkali metal 1,3,5,7-naphthalenetetracarboxylate from the resulting filtrate, and recovering the alkali metal salt precipitated from the formed slurry.

Claim 15

Dependent Claim 124 words

A process for preparing an alkali metal 1,3,5,7-naphthalenetetracarboxylate of high purity, which comprises heating at least one alkali metal naphthalenecarboxylate of the formula ##SPC13## wherein n is an integer of 1 to 4; and M is an alkali metal with the proviso that when n is 4, the four --COOM groups are not present simultaneously in the 1,3,5,7-positions, to a temperature of at least 350°C. in an atmosphere of an inert gas, dissolving the reaction mixture obtained in water, adjusing the alkali ion concentration of the resulting aqueous solution to at least 6 g-alkali ion/ 1000 g-water, hot filtering the solid substance precipitated, then precipitating an alkali metal 1,3,5,7-naphthalenetetracarboxylate from the resulting filtrate, and recovering the alkali metal salt precipitated from the formed slurry.

Claim 16

Dependent Claim 75 words

A process for preparing a 3,7-dialkali 1,3,5,7-naphthalenetetracarboxylate of the formula ##SPC14## wherein M is an alkali metal, which comprises bringing a tetraalkali metal 1,3,5,7-naphthalenetetracarboxylate of the formula ##SPC15## wherein M is the same as defined above, into contact with a mineral acid in an amount of not more than 2.5 equivalents per mol of the tetraalkali metal 1,3,5,7-carboxylate or an organic acid having a pKa value of not more than 5.4 in an aqueous medium.

Claim 17

Dependent Claim 75 words

A process for preparing a 3,7-dialkali 1,3,5,7-naphthalenetetracarboxylate of the formula ##SPC14## wherein M is an alkali metal, which comprises bringing a tetraalkali metal 1,3,5,7-naphthalenetetracarboxylate of the formula ##SPC15## wherein M is the same as defined above, into contact with a mineral acid in an amount of not more than 2.5 equivalents per mol of the tetraalkali metal 1,3,5,7-carboxylate or an organic acid having a pKa value of not more than 5.4 in an aqueous medium.

Claim 18

Dependent Claim 33 words

A process for preparing a 3,7-dialkali metal 1,3,5,7-naphthalenetetracarboxylate, which comprises reacting 1,3,5,7-naphthalenetetracarboxylic acid or a monoalkali metal salt thereof or a mixture of said acid and said salt with a tetraalkali metal 1,3,5,7-naphthalenetetracarboxylate.

Claim 19

Dependent Claim 33 words

A process for preparing a 3,7-dialkali metal 1,3,5,7-naphthalenetetracarboxylate, which comprises reacting 1,3,5,7-naphthalenetetracarboxylic acid or a monoalkali metal salt thereof or a mixture of said acid and said salt with a tetraalkali metal 1,3,5,7-naphthalenetetracarboxylate.

Annuity Stage	Window Opens	Payment Deadline	Surcharge Period Until	Estimated Fee	Status
3.5 Years (Year 4)	1979-05-04	1979-11-03	1980-05-04	$2000.00	Window Closed / Lapsed
7.5 Years (Year 8)	1983-05-04	1983-11-03	1984-05-04	$3760.00	Window Closed / Lapsed
11.5 Years (Year 12)	1987-05-04	1987-11-03	1988-05-04	$7700.00	Window Closed / Lapsed

1,3,5,7-Naphthalenetetracarboxylic acids and process for preparation thereof

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