Thermal Pre-Ignition Agents

Abstract

The invention relates to thermal pre-ignition agents and to their use as thermal fuses, in particular for use in gas generators of motor-vehicle safety systems.

Description

The Examples show that the mixtures defined according to the invention have deflagration temperatures in the range from 178 to 208° C. and are to be regarded as stable according to the requirements of the automotive industry.

The present invention specifically provides:

Thermal pre-ignition agents which contain as a component dipicrylaminoethyl nitrate (DPN) in amounts by weight of from 10 to 100%.

Thermal pre-ignition agents which, in addition to DPN, contain nitrogen-containing compounds, on their own or in mixtures, in amounts by weight of from 0 to 90%, such as, for example, nitroguanidine, nitroaminoguanidine, nitrotriazolone, derivatives of tetrazole, such as 5-aminotetrazole, ditetrazolylamine, ditetrazole and salts thereof, nitraminotetrazole and its salts, such as ammonium nitraminotetrazole and aminoguanidinium nitraminotetrazole, aminoguanidine nitrate, diaminoguanidine nitrate, triaminoguanidine nitrate, guanidine nitrate, dicyandiamidine nitrate, diaminoguanidine azotetrazolate.

Thermal pre-ignition agents which, in addition to DPN and the above-mentioned nitrogen-containing compounds, on their own or in mixtures, contain oxidising agents, on their own or in mixtures, in amounts by weight of from 10 to 90%, such as, for example, nitrates of the alkali or alkaline earth metals or of ammonium, such as sodium nitrate or potassium nitrate, perchlorates of the alkali or alkaline earth metals or of ammonium, peroxides of the alkaline earth metals or of zinc.

Thermal pre-ignition agents which, in addition to DPN, the above-mentioned nitrogen-containing compounds, on their own or in mixtures, and/or the above-mentioned oxidising agents, on their own or in mixtures, contain reducing agents, on their own or in mixtures, in amounts by weight of from 1 to 80%, such as, for example, aluminium, titanium, titanium hydride, boron, boron hydride, zirconium, zirconium hydride, silicon, graphite, activated carbon, carbon black.

Thermal pre-ignition agents which, in addition to DPN, the above-mentioned nitrogen-containing compounds, on their own or in mixtures, the above-mentioned oxidising agents, on their own or in mixtures, and/or the above-mentioned reducing agents, on their own or in mixtures, contain binders, on their own or in mixtures, in amounts by weight of from 1 to 80%, such as, for example, cellulose and derivatives thereof, polyvinylbutyrals, polynitropolyphenylene, polynitrophenyl ether, Plexigum, polyvinyl acetate and copolymers.

Thermal pre-ignition agents which, in addition to DPN, the above-mentioned nitrogen-containing compounds, on their own or in mixtures, the above-mentioned oxidising agents, on their own or in mixtures, the above-mentioned reducing agents, on their own or in mixtures, and/or the above-mentioned binders, on their own or in mixtures, contain high-energy additives, on their own or in mixtures, in amounts by weight of from 10 to 80%, such as, for example, hexogen, octogen and nitrocellulose.

Thermal pre-ignition agents which, in addition to DPN, the above-mentioned nitrogen-containing compounds, on their own or in mixtures, the above-mentioned oxidising agents, on their own or in mixtures, the above-mentioned reducing agents, on their own or in mixtures, the above-mentioned binders, on their own or in mixtures, and/or the above-mentioned high-energy additives, on their own or in mixtures, contain combustion moderators and processing aids, on their own or in mixtures, in amounts by weight of from 0.1 to 20%, such as, for example, ferrocene and derivatives, acetonylacetates, salicylates, silicates, silica gels, boron nitride.

Claims

1. Thermal pre-ignition agents for gas generators, characterised in that they contain from 10 to 100 wt. % dipicrylaminoethyl nitrate.

2. Thermal pre-ignition agents according to claim 1, characterised in that they contain from 0 to 90 wt. % of an additive or plurality of additives.

3. Thermal pre-ignition agents according to claim 2, characterised in that the additives are selected from: nitroguanidine, nitroaminoguanidine, nitrotriazolone, derivatives of tetrazole and/or salts thereof, nitraminotetrazole and/or its salts, aminoguanidine nitrate, diaminoguanidine nitrate, triaminoguanidine nitrate, guanidine nitrate, dicyandiamidine nitrate, diaminoguanidine azotetrazolate; nitrates of the alkali and/or alkaline earth metals and/or of ammonium, perchlorates of the alkali and/or alkaline earth metals and/or of ammonium, peroxides of the alkaline earth metals and/or of zinc; aluminium, titanium, titanium hydride, boron, boron hydride, zirconium, zirconium hydride, silicon, graphite, activated carbon, carbon black; cellulose and/or derivatives thereof, polyvinylbutyrals, polynitropolyphenylene, polynitrophenyl ether, Plexigum, polyvinyl acetate and copolymers; hexogen, octogen; ferrocene and/or derivatives thereof, acetonylacetates, salicylates, silicates, silica gels, boron nitride.

4. Thermal pre-ignition agents according to one or more of claims 1 to 3, characterised in that they contain from 10 to 90 wt. %, preferably from 25 to 75 wt. %, particularly preferably from 40 to 60 wt. %, dipicrylaminoethyl nitrate and from 10 to 90 wt. %, preferably from 25 to 75 wt. %, particularly preferably from 40 to 60 wt. %, of an oxidising agent.

5. Thermal pre-ignition agents according to one or more of claims 1 to 4, characterised in that they contain from 10 to 90 wt. %, preferably from 10 to 50 wt. %, particularly preferably from 10 to 30 wt. %, dipicrylaminoethyl nitrate, from 10 to 90 wt. %, preferably from 10 to 60 wt. %, particularly preferably from 20 to 40 wt. %, of a nitrogen-containing compound and from 10 to 90 wt. %, preferably from 25 to 75 wt. %, particularly preferably from 40 to 60 wt. %, of an oxidising agent.

6. Thermal pre-ignition agents according to one or more of claims 1 to 5, characterised in that the oxidising agent is selected from one or more of the nitrates of the alkali and/or alkaline earth metals and/or of ammonium, of the perchlorates of the alkali and/or alkaline earth metals and/or of ammonium, of the peroxides of the alkaline earth metals and/or of zinc.

7. Thermal pre-ignition agents according to one or more of claims 1 to 6, characterised in that the nitrogen-containing compound is selected from one or more of nitroguanidine, nitroaminoguanidine, nitrotriazolone, derivatives of tetrazole and/or salts thereof, nitraminotetrazole and/or its salts, aminoguanidine nitrate, diaminoguanidine nitrate, triaminoguanidine nitrate, guanidine nitrate, dicyandiamidine nitrate, diaminoguanidine azotetrazolate.

8. Thermal pre-ignition agents according to one or more of claims 1 to 7, characterised in that they contain from 1 to 80 wt. %, preferably from 1 to 40 wt. %, particularly preferably from 1 to 15 wt. %, of a reducing agent.

9. Thermal pre-ignition agents according to one or more of claims 1 to 8, characterised in that the reducing agent is selected from one or more of aluminium, titanium, titanium hydride, boron, boron hydride, zirconium, zirconium hydride, silicon, graphite, activated carbon, carbon black.

10. Thermal pre-ignition agents according to one or more of claims 1 to 9, characterised in that they contain from 1 to 80 wt. %, preferably from 1 to 40 wt. %, particularly preferably from 1 to 20 wt. %, of a binder.

11. Thermal pre-ignition agents according to one or more of claims 1 to 10, characterised in that the binder is selected from one or more of cellulose and derivatives thereof, polyvinylbutyrals, polynitropolyphenylene, polynitrophenyl ether, Plexigum, polyvinyl acetate and copolymers.

12. Thermal pre-ignition agents according to one or more of claims 1 to 11, characterised in that they contain from 10 to 80 wt. %, preferably from 10 to 50 wt. %, particularly preferably from 10 to 30 wt. %, high-energy additives.

13. Thermal pre-ignition agents according to one or more of claims 1 to 12, characterised in that the high-energy additives are selected from one or more of hexogen, octogen and nitrocellulose.

14. Thermal pre-ignition agents according to one or more of claims 1 to 13, characterised in that they contain from 0.1 to 20 wt. %, preferably from 0.1 to 10 wt. %, combustion moderators and processing aids.

15. Thermal pre-ignition agents according to one or more of claims 1 to 14, characterised in that the combustion moderators and processing aids are selected from one or more of ferrocene and derivatives thereof, acetonylacetates, salicylates, silicates, silica gels and boron nitride.

16. Use of a thermal pre-ignition agent according to one or more of claims 1 to 15 as thermal fuse in gas generators for motor vehicle safety systems.