JPH07232989A - Automatically ignitable explosive composition - Google Patents

Abstract

PURPOSE:To obtain the explosive composition that can be safely handled and generates the combustion product contg. no harmful substance and has excellent preservation stability and a function capable of being automatically ignited in a high temp. region with low variance in the ignition temp. by blending a carbohydrate, an oxohalate and a metal oxide, each of which has specified particle size, in specified ratios. CONSTITUTION:This composition is obtained by blending the following components together: (A) 95.0 to 1.0wt.% of a carbohydrate having 0.5 to 0.0001mm average particle size; (B) 95.0 to 1.0wt.% of an oxohalate having 1.0 to 0.0001mm average particle size; (C) 30. 0 to 0.01wt.% of a metal oxide having <=0.5mm particle size. In this blending, any one or both of the carbohydrate and the oxohalate are coated with the metal oxide, or the three components (A), (B) and (C) are uniformly mixed. Preferably, the component (A) is cane sugar and the components (B) is a chlorate, perchlorate, bromate, perbromate, iodate or periodate alone or a mixture thereof and the component (C) is calcium oxide, magnesium oxide or zinc oxide alone or a mixture thereof.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gunpowder composition used for a gas generator for rapidly launching a projectile such as a rocket or a gas generator for rapidly inflating an airbag of a vehicle or the like. Or an autoignitable explosive composition used for pyrotechnics or smoke.

[0002]

2. Description of the Related Art In the case of a gas generator for inflating an airbag of a vehicle or the like, the gas generating agent used in this gas generator has an appropriate burning rate, good heat aging resistance, and generated gas. Since it is required to be harmless, those containing sodium azide as a main component have been used.

On the other hand, as the non-sodium azide-based gas generating agent, a combination of an organic substance such as tetrazole, triazole, organic acid and saccharide with an oxidizing agent of potassium perchlorate, ammonium perchlorate, potassium nitrate and the like. Things are known. Other examples include black powder, smokeless powder, composite propellant and the like.

As a gas generating agent for applications other than air bag gas generators, a combination of a saccharide used in a smoke screen for generating a large amount of smoke with gas and a chlorate or perchlorate, Combinations of perchlorates or chlorates with sugars used to vaporize insecticides in the air with gas are known.

[0005]

A gas generating agent containing sodium azide as a main component generates hydrazoic acid when it absorbs moisture. This hydrazoic acid has the drawback that it is extremely sensitive to shock, explodes easily, and is extremely toxic to the human body, so its storage container must be tightly sealed and kept out of the atmosphere. . Further, when the sodium azide is burned, a strong alkaline substance is generated. The filter function must be strictly controlled so that this substance does not become mist and is not discharged to the outside of the gas generator. Therefore, the sodium azide-based gas generating agent has a drawback in terms of safety.

[0006] Since the disadvantages of the above-mentioned sodium azide are disliked, various non-sodium azide-based gas generating agents have been proposed, but tetrazole compounds and triazole compounds have a large pressure dependency of combustion, and a good combustion rate is obtained. I can't control it. Further, it lacks high-temperature stability and cannot endure long-term heat aging resistance near 100 ° C.

[0007] Black powder is excellent in terms of heat aging resistance and burning rate, but since sulfur is contained in the main component, the toxicity of the generated gas is strong, and under the condition that the gas may come into contact with the human body. Can not be used in. Smokeless gunpowder or nitrocellulose lacks heat aging resistance and undergoes self-decomposition, which has the drawback that the burning rate changes during storage.

Explosives used for smoke and fire that generate a large amount of gas and smoke usually do not have good heat stability because they do not require heat aging resistance. In addition, explosives for volatilizing insecticides are not particularly required to have heat aging resistance, and thus have poor thermal stability.

Therefore, it is said that black explosives which are non-azide type gas generating agents and have good heat aging resistance lack safety, and tetrazole-based, smokeless explosives and smoke explosives excellent in safety lack heat aging resistance. There was a problem.

Further, this kind of explosive is required to have a function of automatically igniting in a specific temperature range from the viewpoint of preventing explosion at the time of heating. However, conventional explosives have a problem in that the temperature at which they are automatically ignited varies, and a predetermined automatic ignition function cannot be obtained.

In order to eliminate the above-mentioned drawbacks, the present invention provides an auto-igniting explosive composition which is not only excellent in safety and heat aging resistance but also has a reliable auto-ignition function in a specific high temperature range. With the goal.

[0012]

That is, the self-igniting explosive composition of the present invention contains a carbohydrate, a chlorate and a metal oxide, and has an auto-ignition function within a predetermined temperature range. Also, when used in a place where heat is difficult to transfer,
It can also be an autoignitable explosive composition comprising carbohydrates, chlorates, metal oxides and synthetic resins.

Carbohydrates in the autoignition powder composition are gasifying components, and oxohalogenates are oxygen supplying components, and the ignition temperature within a predetermined temperature range can be selected by a combination of both. Although the usage mode in which it is exposed to a high temperature up to the ignition temperature is common, especially metal oxides are stabilizing components that contribute to the high temperature stability at high temperatures up to the ignition temperature. The synthetic resin is a binder for granulating the self-igniting explosive composition, and contributes to the improvement of the thermal conductivity of the explosive composition.

In order to obtain an ignition temperature and a compatible burning rate in a given temperature range, the carbohydrate is preferably 95.
0-1.0% by weight, preferably 9 oxohalogenates
5.0-1.0% by weight, preferably 30.
0 to 0.01% by weight, preferably synthetic resin 0.5 to 2
It is 0.0% by weight. This composition ratio may be varied within the above composition range according to the combustion rate suitable for the required site of the gas generator, based on the stoichiometric ratio required for combustion of the carbohydrate and the oxohalogenate. In particular, the metal oxide is preferably 30.0 to 0.01% by weight, particularly preferably 1
It is 0.0 to 1.0% by weight. And, it may be changed as appropriate in order to adjust the combustion speed according to the internal structure of the gas generator used. If the carbohydrate is out of this range, the burning rate may be abnormal, and if the oxohalogenate is out of this range, the auto-ignition function may be impaired, and the metal oxide is out of this range. If so, heat aging resistance and automatic ignition function may be impaired. When heat is difficult to transfer to the auto-ignitable explosive composition, if the synthetic resin is out of this range,
The autoignition temperature may change significantly depending on the degree of mixing.

The particle size of carbohydrates, oxohalogenates and metal oxides has a great influence on the reliable ignitability and high temperature stability. The average particle size of the carbohydrate is preferably 0.5 mm to 0.
The average particle size of the oxohalic acid salt is preferably 1.0 mm to 0.0001 mm, and the particle size of the metal oxide is preferably 0.5 mm or less. If the particle size of the carbohydrate is out of this range, the heat aging resistance may be impaired, and if the particle size of the oxohalogenate is out of this range, the burning rate may be different and the metal oxide If the particle size is outside this range, the heat aging resistance and the automatic ignition function may be impaired. Particularly, the particle size of the metal oxide is preferably 1/10 or less of the particle size of the carbohydrate.

The average particle size of the metal oxide is 1/10 or less of the average particle size of at least one of the carbohydrate and the oxohalogenate, and at least one of the carbohydrate and the oxohalogenate is coated with the metal oxide. As a result, reliable ignition performance and high temperature stability are secured. In the coating method, first, a carbohydrate and a metal oxide are mixed and the surface of the carbohydrate is coated with the metal oxide. Separately, an oxohalogenate and a metal oxide are mixed, and the surface of the oxohalogenate is coated with the metal oxide. Next, both are mixed. This operation improves the high temperature stability, and the burning rate is controlled by the coating amount.

When the average particle size of each component is 0.05 mm or less, the three components may be mixed at the same time.

Among the components, carbohydrates include sucrose,
Lactose, glucose, powdered cellulose, dextrin, wood flour and the like can be used alone or in a mixture. It is preferable to use sucrose as a substance having a preferable auto-ignition temperature of 165 to 220 ° C.

The oxohalogenates of each component include chlorates such as potassium chlorate, sodium chlorate and barium chlorate, as well as bromates such as calcium bromate and sodium bromate and potassium iodate. , Iodate such as sodium iodate, perchlorate, perbromate,
Although periodate and the like can be used, chlorate is preferable, and potassium chlorate is particularly preferable, from the viewpoint of easy handling.

As the metal oxide of each component, magnesium oxide, calcium oxide, zinc oxide, potassium oxide, sodium oxide, cesium oxide and the like can be used. Magnesium oxide, calcium oxide, and zinc oxide are preferable from the viewpoint of easy handling, but light magnesium oxide is particularly preferable from the viewpoint of fine and uniform particle size.

As the synthetic resin among the components, silicone resin, urethane resin, polyester, acrylic resin,
Butyl rubber etc. can be used. A one-part room temperature-curable silicone resin is particularly preferable from the viewpoint of easy handling and thermal stability. The granulation is performed by mixing carbohydrates, oxohalogenates, and metal oxides, then adding a synthetic resin and kneading.

[0022]

This type of self-igniting explosive composition may be exposed to a high temperature or may be left unignited for a long period of time, so that it is required to have high temperature stability without impairing the ignition function. This high temperature stability is achieved by the metal oxides in the autoignitable explosive composition.
That is, the state where the carbohydrate and the oxohalogenate are stably separated by the metal oxide is ensured, and even if the carbohydrate is slightly dissolved at the high temperature before the automatic ignition, the oxohalate does not reach the predetermined level. Carbohydrates that melted at the auto-ignition temperature reached the oxohalogenate salt and ignited.

Further, in the case of automatic ignition, the temperature of the above-mentioned automatic pyrotechnic powder composition is raised by heating, but since the carbohydrate and the oxohalogenate are separated by the metal oxide as described above, the state in which the carbohydrate is dissolved May not be stable and the auto-ignition temperature may vary. Synthetic resins play a role in reducing this variation and consequently lowering the automatic ignition temperature. This synthetic resin properly bridges between the carbohydrate, oxohalogenate, and metal oxide, and heat conduction through the part of the bridge allows the carbohydrate to be stably dissolved. The phenomenon is that oxohalogenates lead to automatic ignition.

In order to maintain such a state, it is desirable that the metal oxide has a predetermined particle size and a predetermined content, and the synthetic resin also has a predetermined content. A specific mixed form of the metal oxide and the synthetic resin is desirable.

[0025]

EXAMPLES The present invention will be specifically described below with reference to examples and comparative examples, but the present invention is not limited to these examples. First, an example of a four-component autoignition powder composition of carbohydrate / oxohalogenate / metal oxide / synthetic resin will be described. In the examples,% is weight%
Represents

[Examples 1 to 3 and Comparative Examples 1 to 6] The combinations shown in Table 1 were mixed at the following ratios to give an autoignition powder composition. Sucrose (manufactured by Taito Co., Ltd.) 23.0% by weight (Examples 1 and 2 and Comparative Examples 1 and 4) Dextrin (reagent: manufactured by Kishida Chemical Co., Ltd.) 23.0% by weight (Examples 3 and 4 and Comparative Example 2) , 5) Cellulose (reagent: Wako Pure Chemical Industries, Ltd.) 23.0 wt% (Examples 5, 6 and Comparative Examples 3, 6) Potassium chlorate (reagent: Kanto Chemical Co., Ltd.) 74.0 wt% (implementation Examples 1 to 6) 77.0% by weight (Comparative Examples 1 to 6) MgO (reagent: Wako Pure Chemical Industries, Ltd.) 2.0% by weight (Examples 1, 2, 5 and Comparative Example 1) ZnO (reagent: Sum) Kou Pure Chemical Industries) 2.0 wt% (Example 4 and Comparative Example 2) CaO (reagent: Wako Pure Chemical Industries, Ltd.) 2.0 wt% (Example 6 and Comparative Example 3) Silicone resin (one-liquid room temperature curing) Type) (trade name "Shin-Etsu Silicone KE441T": manufactured by Shin-Etsu Chemical Co., Ltd.) (Examples 1 and 3 and Comparative Examples 4 to 6) Urethane resin (Brand name "HIBON 4601": Hitachi Chemical Polymer Co., Ltd.) (Example 2) Butyl rubber (Brand name "HIBON 1010A": Hitachi Chemical Polymer Co., Ltd.) (Example 4) Polyester resin (Brand name "HIBON" 7031L ": manufactured by Hitachi Chemical Polymer Co., Ltd.) (Example 6)

The mixing was carried out by mixing the carbohydrate and the metal oxide, separately mixing potassium chlorate and the metal oxide, and then mixing the two together. Then, add synthetic resin,
After kneading and granulating for a minute, the mixture was left to cure at room temperature for 48 hours.

The obtained autoignitable explosive composition was burned with 8 g of the granular particles in a container made of a stainless steel container having an internal volume of 1 liter equipped with a pressure sensor. The pressure was measured. (1 liter tank test)

For the ignition of the self-igniting explosive composition, a rodan lead ignition ball and a detonator containing 0.6 g of boron / potassium nitrate igniter were used. The ignition time was the time from when the ignition current of the detonator was cut off until pressure was generated.

Further, the self-igniting explosive composition has a temperature of 120 ° C.
A temperature history of × 100 hours was given to examine the heat aging resistance.
The automatic ignition temperature of the explosive composition is determined by a differential thermal analyzer (type name D
SC220: manufactured by Seiko Denshi Kogyo Co., Ltd.). The results of the above tests are summarized in Table 1.

[0031]

[Table 1]

In Examples 1 to 6, since the conditions satisfy the specifications of the present invention, the initial performance and 120 ° C. × 100
Almost no change was observed in the performance after the heat aging for a certain period of time, and the reproducibility of the auto-ignition temperature was particularly good.

In Comparative Examples 1 to 3, since the synthetic resin was not present, the auto-ignition temperature was high, and the temperature was 120 ° C. × 10.
After 0 hour heat aging, the auto-ignition temperature further increased. In Comparative Examples 4 to 6, since no metal oxide was present, 120
No ignition occurred after heat aging at 100 ° C. for 100 hours. Moreover, the automatic ignition temperature could not be measured. The properties after heat aging did not change in Examples and Comparative Examples 1 to 3, but in Comparative Examples 4 to 6, the color changed to blackish brown.

As described above, the self-igniting explosive composition of the present invention has a function of automatically igniting in a specific high temperature range.
Stable combustion performance was maintained even after heat aging at 0 ° C for 100 hours.

Next, examples of a self-igniting explosive composition of a three-component system of carbohydrate / oxohalogenate / metal oxide will be described.

[Examples 1 to 3 and Comparative Examples 1 to 6] The combinations shown in Table 2 were mixed in the following proportions to give explosive compositions. Sucrose (manufactured by Taito Co., Ltd.) 23.0 wt% (Example 1 and Comparative Examples 1 and 2) Dextrin (reagent: Kishida Chemical Co., Ltd.) 23.0 wt% (Example 2 and Comparative Examples 3 and 4) Cellulose (Reagent: Wako Pure Chemical Industries, Ltd.) 23.0 wt% (Example 3 and Comparative Examples 5 and 6) Potassium chlorate (Reagent: Kanto Chemical Co., Ltd.) 74.0 wt% (Examples 1 to 3) 77 0.0 wt% (Comparative Examples 1 to 7) MgO (reagent: Wako Pure Chemical Industries, Ltd.) 2.0 wt% (Example 1) ZnO (reagent: Wako Pure Chemical Industries, Ltd.) 2.0 wt% (Example 2) ) CaO (reagent: Wako Pure Chemical Industries, Ltd.) 2.0 wt% (Example 3)

The mixing was carried out by mixing the carbohydrate and the metal oxide, separately mixing potassium chlorate and the metal oxide, and then mixing them together.

The obtained self-igniting explosive composition was burned in an amount of 5 liters as powder in this container by using a test device having a pressure sensor attached to a stainless steel container having an internal volume of 1 liter. The pressure was measured. (1 liter tank test)

For ignition of the self-igniting explosive composition, a lead igniter rodan and a detonator containing 0.6 g of boron / potassium nitrate igniter were used. The ignition time was the time from when the ignition current of the detonator was cut off until pressure was generated.

Further, the self-igniting explosive composition has a temperature of 120 ° C.
The heat aging resistance was examined by giving a temperature history of × 100 hours and 107 ° C × 400 hours. The automatic ignition temperature of the explosive composition was measured by using a differential thermal analyzer (model name DSC220: manufactured by Seiko Instruments Inc.). The results of the above tests are summarized in Table 2.

[0041]

[Table 2]

In Examples 1 to 3, since the conditions satisfy the specifications of the present invention, the initial performance and 120 ° C. × 100
After the heat aging for a while, the performance did not change much.

In Comparative Examples 1 to 6, since no metal oxide was present, all ignition failed after heat aging at 120 ° C. for 100 hours. Moreover, the automatic ignition temperature could not be measured. In addition, in the properties after heat aging, in all of the comparative examples, the properties changed to blackish brown as compared with the properties of the examples that did not change.

As described above, the self-igniting explosive composition of the present invention has a function of automatically igniting in a specific high temperature range.
Stable combustion performance was maintained even after heat aging at 0 ° C for 100 hours.

[0045]

EFFECTS OF THE INVENTION The self-igniting explosive composition of the present invention is safe to handle and does not contain harmful substances in combustion products.
It has excellent long-term storage stability, has the function of automatically igniting in a specific high temperature range, and has little variation in the ignition temperature.
Most suitable as explosives for gas generators and smoke.

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Ayumi Kimura 3903-39, Abundant Town, Himeji City, Hyogo Prefecture Nihon Kayaku Co., Ltd. Himeji Factory

Claims (13)

[Claims] 1. A pyrophoric composition comprising a carbohydrate, an oxohalogenate and a metal oxide. 2. The carbohydrate of the pyrophoric powder composition has an average particle size of 0.5 mm to 0.0001 mm, and the oxohalic acid salt has an average particle size of 1.0 mm to 0.0001 m.
The self-igniting explosive composition according to claim 1, wherein the particle size of the metal oxide is 0.5 mm and the particle size of the metal oxide is 0.5 mm or less. 3. The autoignitable explosive composition comprises 95.0 to 1.0% by weight of carbohydrate and 95.
The self-igniting explosive composition according to claim 1, wherein the content of the metal oxide is 0 to 1.0% by weight and the content of the metal oxide is 30.0 to 0.01% by weight. 4. The pyrophoric composition of claim 1, wherein one or both of the carbohydrate and oxohalogenate salt of the pyrotechnic composition are coated with a metal oxide. 5. The self-igniting explosive composition according to claim 1, wherein the carbohydrate, the oxohalogenate and the metal oxide of the self-igniting explosive composition are uniformly mixed. 6. The carbohydrate of the pyrophoric powder composition is sucrose, and the oxohalogenate is chlorate, perchlorate, bromate, perbromate, iodate or periodate. 2. The self-igniting explosive composition according to claim 1, wherein the metal oxide is calcium oxide, magnesium oxide, zinc oxide alone or a mixture thereof. 7. A pyrophoric composition comprising a carbohydrate, an oxohalogenate, a metal oxide and a synthetic resin. 8. The carbohydrate of the self-igniting explosive composition has an average particle size of 0.5 mm to 0.0001 mm, and the oxohalic acid salt has an average particle size of 1.0 mm to 0.0001 m.
8. The self-igniting explosive composition according to claim 7, wherein m is a particle size of the metal oxide is 0.5 mm or less. 9. The autoignitable explosive composition contains 95.0 to 1.0% by weight of carbohydrate and 95.
The self-igniting explosive composition according to claim 7, wherein 0 to 1.0% by weight, 30.0 to 0.01% by weight of metal oxide, and 0.5 to 20.0% by weight of synthetic resin. 10. The explosive composition of claim 7, wherein one or both of the carbohydrate and the oxohalogenate salt of the pyrophoric explosive composition are coated with a metal oxide. 11. The self-igniting explosive composition according to claim 7, wherein the carbohydrate, the oxohalogenate and the metal oxide of the self-igniting explosive composition are uniformly mixed. 12. The explosive composition according to claim 7, wherein the mixture of the carbohydrate, the oxohalogenate and the metal oxide of the self-igniting explosive composition is granulated with a synthetic resin. 13. The carbohydrate of the pyrophoric powder composition is sucrose and the oxohalogenate is chlorate, perchlorate, bromate, perbromate, iodate or periodate. Or a mixture thereof, the metal oxide is calcium oxide, magnesium oxide, zinc oxide alone or a mixture thereof, and the synthetic resin is any of silicone resin, urethane resin, polyester, acrylic resin, and butyl rubber. The self-igniting explosive composition according to claim 7.