JPH04228490A - Gas producing agent composition - Google Patents

Abstract

PURPOSE:To provide a gas producing agent composition capable of improving the strength of pellets without causing generation of toxic gases and deterioration in combustion rate or operating efficiency in producing the pellets and providing a produced gas at a low temperature. CONSTITUTION:A gas producing agent composition containing a sodium azide oxidizing agent as a principal component and 5-25wt.% clayey substance containing >=40wt.% silicon dioxide (5-20wt.% clayey substance containing >=50wt.% silicon) or an azide of an alkali metal or an alkaline earth metal and calcined manganese dioxide calcined in an atmosphere at 250-500 deg.C as a principal component.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gas generating composition used in a gas generating device (hereinafter simply referred to as a "gas generator") for inflating an air bag. This airbag is mounted, for example, on a steering wheel inside a vehicle and is used to protect passengers from collisions.

0002

[Prior Art] A gas generating agent consisting of sodium azide and various oxidizing agents is made into pellets and incorporated into a gas generator, which is then burned to generate nitrogen gas.
Gas generating agents that inflate airbags are known. The gas generating agent used in the gas generator is required to have a very high combustion rate because the gas generator needs to inflate the airbag within several tens of milliseconds from ignition. If this combustion rate is slow, the gas generant pellets must be made thinner to increase the combustion surface area in order to obtain the desired combustion characteristics.

[0003] Furthermore, the gas generating agent pellets housed in the gas generator are exposed to severe vibrations and severe temperature conditions with large fluctuations in the interior of an automobile for many years.
The strength of the gas generating agent pellets is required to be strong. Furthermore, the gas composition emitted from the gas generator must be harmless to humans, and the concentration of harmful carbon monoxide and cyanide must be below a certain level or must not be detected. .

[0004] It is generally known that adding a binder is effective in increasing the strength of gas generating agent pellets. Binders can be broadly classified into organic binders and inorganic binders, but it is not preferable to apply various organic binders to gas generating agents for airbags for the following reasons. That is, the reason is that the carbon component in the organic binder easily becomes carbon monoxide or cyanide during the combustion process, and harmful gases are contained in the nitrogen gas. In particular, cyanide is extremely toxic and must not be produced even in trace amounts.

Taking these points into consideration, a means for improving the strength of gas generating agent pellets was proposed in Japanese Patent Publication No. 56-13735.
No. 63-166427. Japanese Patent Publication No. 56-13735 discloses a gas generating composition in which a compound represented by the following general formula 1 is blended into a gas generating composition comprising an azide and an oxidizing agent.

[0006]

[Chemical formula 1] (Al2O3)m (Mx O)n (SiO
2) p, qH2O (M is Li, Na, K, Sr
, Mg or Ca, and x represents 1 or 2. m and n represent 0 or a positive number. However, m and n do not become 0 at the same time. p is a positive number, and q is 0 or a positive number. ) As specific examples of the compound represented by Formula 1, aluminum silicate, magnesium silicate, magnesium aluminate silicate, water glass, and combinations thereof are disclosed. All of these compounds are synthetic products. This gas generating agent composition is effective in improving the strength of gas generating agent pellets.

[0007] In addition, JP-A-63-166427 discloses that 2 to 6% by weight of a gas generating agent containing an azide as a main component.
A gas generant composition comprising graphite fibers is disclosed. Specifically, the following compositions are shown. Sodium azide 61-68% by weight Sodium nitrate 0-5% by weight Bentonite 0-5% by weight Iron oxide 23-28% by weight
Fumed silica 1-2% by weight Graphite fiber 2-6% by weight This composition improves pellet strength without reducing burn rate.

Further, US Pat. No. 3,996,079 discloses a gas generating composition comprising an azide, nickel oxide or iron oxide as an oxidizing agent, and a small amount (0.5 to 3.0%) of a clay material. has been done. This clay material is effective in improving moldability. Additionally, U.S. Patent No. 493
No. 1111 discloses a first oxidizing agent comprising (a) about 50-70% by weight of an azide, (b) about 2-30% by weight of a metal oxide, and (c) about 2-40% by weight of a metal oxide. A combustion rate regulator consisting of a second oxidizing agent consisting of a nitrate or a perchlorate and a clay substance (the ratio of the second oxidizing agent and the clay substance is 1:1 to
1:8) is disclosed. This composition then produces a gas with a high burn rate and is non-toxic.

[0009]

[Problems to be Solved by the Invention] However, the gas generating composition described in Japanese Patent Publication No. 56-13735 is
There is a problem in that as the amount of the compound whose general formula is represented by Formula 1 increases, the combustion rate of the gas generating composition decreases. This is also clear from the fact that the deployment time of the airbag described in the Examples of the above patent increases as the amount of the above compound added increases.

[0010] As the combustion rate decreases, it is necessary to reduce the thickness of the pellet to increase the combustion surface area in order to inflate the airbag within a predetermined time. However, such measures lead to a decrease in pellet strength. Further, even if an inorganic binder is added to improve pellet strength, it is meaningless if the combustion rate is extremely reduced as described above. Note that the above publication does not disclose clay materials.

[0011] Furthermore, when the gas generating agent composition described in JP-A No. 63-166427 is to be manufactured into gas generating agent pellets using an ordinary commercially available tableting machine, the gas generating agent composition is first compressed into a certain volume. Measure out the gas generating agent and then squeeze. At this time, in order to stably produce pellets with a constant dosage and a constant thickness, the gas generating agent before compression needs to have fluidity. Therefore, the gas generating agent is 0.1 to
It is common to granulate to about 1.0 mm.

However, in this gas generating composition, the component that improves pellet strength without reducing the combustion rate is graphite fiber. 2 to 6 fibrous substances such as graphite fibers
Since a gas generating agent composition containing % by weight cannot obtain good fluidity, it is difficult to granulate it, and there is a problem in that it causes a decrease in workability during production of gas generating agent pellets.

[0013] Furthermore, since the gas generating agent composition described in US Pat. No. 3,996,079 uses nickel oxide or iron oxide as an oxidizing agent, the oxidation reaction is slow, and therefore, while maintaining a high burning rate, There was a problem that pellet strength could not be improved. Furthermore, in the gas generating composition described in US Pat. No. 4,931,111, a strong secondary oxidizing agent such as nitrate or perchlorate is an essential component in order to obtain the desired performance. The reaction occurs rapidly and the reaction temperature rises. Therefore, the temperature of the generated gas is higher than when only metal oxides are used as oxidizing agents. As a result, many cooling means are required within the gas generator, resulting in the problem that the gas generator cannot be made smaller or lighter.

[0014] Also, a composition is known in which manganese dioxide is used as an oxidizing agent and mixed with an azide.
This composition has the following problems. Azides have chemical properties that, when mixed with heavy metals such as copper, lead, silver, and mercury, produce explosives that are extremely sensitive to handling, such as copper azide, lead azide, silver azide, and mercury azide. Therefore, contact with these heavy metals must be avoided. On the other hand, natural manganese ore is used as a raw material for manufacturing manganese dioxide, which contains a considerable amount of copper and lead impurities.

[0015] Therefore, the manganese dioxide used for the purpose of mixing with the azide must be free of these heavy metal impurities, and it is necessary to sufficiently purify the manganese dioxide. The refining process of manganese dioxide is
A common method is to once reduce manganese dioxide to sulfuric acid-soluble manganese monoxide, and then selectively oxidize only manganese in a sulfuric acid bath.

[0016] This purification step is preferable in that heavy metal impurities, which are a problem when mixed with azide, are removed to 10 ppm or less, but on the other hand, the use of a sulfuric acid bath causes Contains ~5% moisture, i.e. attached and bound water. As a result, compositions containing manganese dioxide and azide produced through the above-described purification process have the problem of containing a large amount of harmful ammonia gas in the gas produced after firing.

[0017] Thus, current gas generant compositions are
There is a problem in that the strength of the pellets cannot be improved without producing toxic gases, reducing the combustion rate, or reducing workability during pellet production. The present invention has been made in view of the above-mentioned problems, and its purpose is to improve the strength of pellets without producing toxic gas, reducing combustion rate, or reducing workability during pellet production. An object of the present invention is to provide a gas generating composition that can perform the following steps. Another object of the present invention is to provide a gas generating composition that produces gas at a low temperature.

[0018]

[Means for Solving the Problems] In order to achieve the above object, in the first invention, a clay material containing sodium azide and an oxidizing agent as main components and 40% by weight or more of silicon dioxide is contained in an amount of 5 to 25% by weight. The gist thereof is a gas generating agent composition containing the following. Further, in the second invention, the main ingredients are an azide of an alkali metal or an alkaline earth metal and calcined manganese dioxide calcined in an atmosphere of 250 to 500 ° C.
5 to 20 clay materials containing 50% by weight or more of silicon dioxide
The gist thereof is a gas generating composition containing % by weight.

Next, each component of the present invention will be explained in sequence. Examples of the azide used in the gas generating agent composition of the present invention include lithium azide, sodium azide,
Potassium azide, rubidium azide, cesium azide,
Examples include calcium azide, magnesium azide, strontium azide, and barium azide. Among these, sodium azide is most suitable in terms of handling safety, thermal safety, and price. The particle size of this azide, especially sodium azide, is preferably 20 μm or less in order to obtain a high combustion rate.

As the oxidizing agent used with sodium azide, conventionally known ones are used, such as perchlorates such as potassium perchlorate and ammonium perchlorate, nitrates such as potassium nitrate and sodium nitrate, Metal oxides such as barium peroxide, manganese dioxide, copper oxide, and iron oxide are preferably used. Among these, manganese dioxide is particularly preferred from the viewpoints of low combustion temperature, high combustion rate, good chemical stability, and low cost when mixed with sodium azide.

[0021] This manganese dioxide is preferably fired in an electric furnace, for example. Firing temperature is 250-500℃
is preferable, and 300 to 400°C is more preferable. If the firing temperature is less than 250°C, moisture cannot be removed sufficiently. Moreover, when the temperature exceeds 500° C., although water can be removed, manganese dioxide decomposes and releases oxygen to become manganese sesquioxide (Mn2O3). This manganese sesquioxide has a weaker function as an oxidizing agent than manganese dioxide, and cannot obtain a sufficiently high combustion rate when mixed with azide. The particle size of this manganese dioxide is preferably 10 μm or less in order to obtain a high combustion rate.

[0022] The gas generating composition of the second invention, which contains such calcined manganese dioxide as an essential component, does not use strong oxidizing agents such as nitrates or perchlorates, so that the oxidation reaction is not radical. Therefore, the combustion temperature is low and low temperature gas can be obtained. As a result, it is possible to reduce the size and weight of the gas generator without requiring as many cooling means as in the past.

Regarding the blending ratio of sodium azide and oxidizing agent, the optimum composition varies depending on the type of oxidizing agent used, but when sodium azide is used as the azide, sodium azide is 40 to 75% by weight. A suitable range is 25 to 60% by weight of the oxidizing agent. Next, the clay material in the present invention refers to a naturally occurring silicate mineral or a substance containing it as a main component, and usually has an average particle size of 4 μm or less. Although it is known that the properties of clay materials vary depending on the place of production and the constituent materials, those containing silicon dioxide in an amount of 40% by weight or more, preferably 50% by weight or more are used. Further, the upper limit thereof is preferably 70% by weight. When the proportion of silicon dioxide is less than 40% by weight, the pellet strength is improved, but the combustion rate is reduced.

For example, when using talc with a silicon dioxide content of 37.6% by weight, 5% by weight of talc is used.
Although the above blending improves the pellet strength, it is unsuitable because the combustion rate decreases. When the ratio of silicon dioxide in the clay material is 40 to 70% by weight, for example, when using kaolinite with a silicon dioxide content of 46.6% by weight, by adding 5% by weight or more, the pellet strength becomes clear. A significant improvement was observed, and no significant decrease in combustion rate was observed.

The characteristic feature of the first invention is that when the proportion of silicon dioxide in the clay material is 60% by weight or more, for example, when using bentonite with a silicon dioxide content of 61.2% by weight, , 5% by weight of bentonite in the composition
With the above blending, a clear improvement in pellet strength can be seen, and the combustion rate is also improved, albeit slightly, compared to a composition without bentonite.

Specific examples of this clay material include kaolinite [Al2Si2O5(OH)4, silicon dioxide content 40-60% by weight], pyrophyllite (silicon dioxide content 50-60% by weight), bentonite (
60-70% by weight), smectite (40-60% by weight), montmorillonite (59.7% by weight)
, illite (for example, 51.2% by weight), halloysite, etc. can be used singly or in combination. Among these, bentonite is the most preferable because when the amount of clay material added is 15% by weight or less, there is no decrease in the burning rate, and in fact, the effect of slightly accelerating the burning rate is observed.

The content of the clay material in the gas generating composition of the present invention is in the range of 5 to 25% by weight, and 5 to 2% by weight.
A range of 0% by weight is preferred. The content of this clay substance is 5
If it is less than % by weight, it is difficult to improve the pellet strength, which is inappropriate. On the other hand, the content is 25% by weight
If the content exceeds 100%, the pellet strength will not improve any further even if the content is increased, the combustion rate will decrease, and as the content of clay material increases, the blending ratio of azide will decrease relatively. This method is unsuitable because a large amount of gas generating agent pellets must be placed in the gas generator, which increases the size and weight of the gas generator.

[0028] Furthermore, the content of clay material is 5 to 25% by weight.
Within this range, the strength of the pellets improves as the content increases, but depending on the composition of sodium azide and various oxidizing agents, when the content of clay substances exceeds 15% by weight, the burning rate gradually decreases. Therefore, the content is most preferably 5 to 15% by weight. The blending ratio of each component of the gas generating composition of the present invention is as follows:
2-72% by weight, calcined manganese dioxide 22-42% by weight
, 5 to 20% by weight of clay material is preferred, and 55% of azide
~65% by weight, calcined manganese dioxide 30-38% by weight,
More preferred is 6-10% by weight clay material. In addition, the azide and calcined manganese dioxide are set at a stoichiometric ratio,
Most preferred is a composition in which the clay material is blended in an amount of 6 to 10% by weight of the total composition.

[0029]

[Operation] In the first aspect of the invention, the clay material containing a predetermined amount of silicon dioxide improves the bonding force of the entire gas generating composition, thereby improving its strength. Furthermore, since no organic binder is used, harmful components such as carbon monoxide and cyanide are not generated when the gas generating agent is combusted. Moreover, since the gas generating composition does not contain a fibrous substance such as graphite fiber, the workability during production of the gas generating composition is not reduced.

[0030] In the second invention, manganese dioxide to be mixed with the azide is preliminarily calcined at 250 to 500°C to remove moisture, particularly bound water, in the manganese dioxide. Therefore, when the gas generating composition obtained by mixing manganese dioxide with azide is combusted, the generation of ammonia based on moisture in the gas after combustion is suppressed.

The clay material mixed with the azide and calcined manganese dioxide improves the strength of the gas generant composition, as described above. By using a clay material containing 50% by weight or more of silicon dioxide in its composition, the oxidation reaction rate during combustion of the gas generating composition is maintained and the burning rate of the gas generating composition is reduced. It is possible to improve the strength of the gas generating composition without causing any damage.

[0032]

[Examples] Examples embodying the present invention will be explained below in comparison with comparative examples. In each example, % by weight is abbreviated as %, and parts by weight are abbreviated as parts. First, an embodiment embodying the first invention and a comparative example thereof will be described. (Example 1) Sodium azide 66.2%, ferric oxide 28.3%,
After adding an appropriate amount of water/acetone to a composition consisting of 5.5% kaolinite (average particle size 3.2 μm), the mixture was mixed for about 20 minutes using a Shinagawa mixer. By straining the mixed wet medicine using a 32-mesh silk net, the particle size is approximately 0.
．． A 5 mm granulated drug was made. After drying the granulated drug, cylindrical pellets with a diameter of 6 mm and a thickness of 3 mm were produced using a rotary tablet press.

[0033] Separately, using a special mold and a manual hydraulic press machine, the granulation agent was used to form a 5 mm x 8 m
A rod-shaped molded product (hereinafter referred to as "strand") of m x 50 mm was produced. The strength of the pellets was tested six times at the same falling height using a falling ball type pellet crushing strength tester, and was expressed as the highest falling height that did not cause crushing in any of the six tests. The falling ball used was 16.
This is a 7g steel ball for bearings. Also, the striking pin has a diameter of 4
An iron pin of mm in diameter was used, and the tip that corresponded to the pellet was machined into a hemispherical shape.

[0034] The burning rate was determined by coating the sides of the strand with epoxy resin to prevent full-scale combustion, and then using a drill with a diameter of 0.5 mm.
Two small holes were made at appropriate intervals in the longitudinal direction, and one blowout fuse for measuring combustion time was passed through each hole. This strand sample was placed on a predetermined fixed table, and under a pressure of 30 atmospheres, a nichrome wire was ignited from one end of the strand, and the moment when the fuse blown when the burning surface passed was electrically measured. The linear burning rate was calculated by dividing the distance between the two by the time difference. The results are shown in Table 1. (Examples 2 to 4) Gas generant compositions having the compositions shown in Table 1 were manufactured in the same manner as in Example 1, and their properties were evaluated in the same manner. The results are shown in Table 1. (Comparative Example 1) A composition consisting of 70% sodium azide and 30% ferric oxide was produced in the same manner as in Example 1, and its properties were evaluated. The results are shown in Table 1. (Comparative Examples 2 and 3) Gas generant compositions having the compositions shown in Table 1 (Comparative Examples 2 and 3) were produced in the same manner as in Example 1, and their properties were evaluated in the same manner. The results are shown in Table 1.

[0035]

[Table 1]

In Table 1, NaN3 manufactured by Fujimoto Chemical Co., Ltd. was used. The average particle size of this NaN3 is 9.63
It was μm. Further, the ferric oxide used was the product name "MAPICO" R-516 manufactured by Titan Industries Co., Ltd., and the kaolinite manufactured by Wako Pure Chemical Industries, Ltd. was used. Table 1
As can be seen from the results shown in
% of the gas generating agents of Examples 1 to 4, the pellet strength is improved. However, when the amount of kaolinite added was 5% or less (Comparative Examples 1 and 2), the pellet strength was low and 15%
% (Comparative Example 3), the combustion rate suddenly decreases. Therefore, the amount of kaolinite added is more than 5%, preferably about 15%. (Examples 5 to 7) The compositions shown in Table 2 were used, except that kaolinite was changed to bentonite (average particle size 1.4 μm) as the clay mineral, and the oxidizing agent was changed from ferric oxide to manganese dioxide. Gas generant compositions were produced in the same manner as in Example 1, and their properties were evaluated in the same manner. The results are shown in Table 2. (Comparative Example 4) A composition consisting of 65% sodium azide and 35% manganese dioxide was produced in the same manner as in Example 1, and its properties were evaluated. The results are shown in Table 2. (Comparative Examples 5 and 6) The compositions shown in Table 2 (Comparative Examples 5 and 6) were produced in the same manner as in Example 1, except that the amount of bennite was changed to the amount shown in Table 2, and the properties were evaluated. The results are shown in Table 2.

[0037]

[Table 2]

In Table 2, manganese dioxide is electrolytic manganese dioxide "FMH" manufactured by Tosoh Corporation, and bentonite is "FMH" manufactured by Kunimine Industries Co., Ltd.
Kunigel VA" was used. The average particle size of the manganese dioxide was 2.11 μm. Also, the specific surface area is BET
As a result of measurement using the method (method of determining the equilibrium adsorption amount using the adsorption properties of gases such as nitrogen and calculating from that), it was 50.7.
m2/g.

As can be seen from the results shown in Table 2, pellet strength is improved in Examples 5 to 7 in which bentonite is blended in an amount of 5 to 25%. Furthermore, the combustion speed is fastest when 15% bentonite is added, and the combustion speed does not decrease even when 25% bentonite is added. However, when the amount of bentonite added is less than 5% (Comparative Examples 4 and 5), the pellet strength decreases, and when it exceeds 25% (Comparative Example 6), the combustion rate decreases rapidly. Therefore, the appropriate amount of bentonite to be added is 5 to 25%. (Comparative Example 7) Sodium azide 55.3%, manganese dioxide 29.7
% and 15% talc (manufactured by Kunimine Kogyo Co., Ltd.) was produced and evaluated in the same manner as in Example 1. As a result, the pellet strength improved to a falling height of 10 cm, but the burning rate significantly decreased to 29.9 mm/sec. (Example 8) Sodium azide 55.3%, manganese dioxide 29.7
%, 5% kaolinite and 10% bentonite was produced in the same manner as in Example 1, and its properties were evaluated. As a result, the pellet strength improved to a falling height of 13 cm, and the burning rate remained almost unchanged at 43.4 mm/sec. (Comparative Example 8) Sodium azide 55.3%, manganese dioxide 29.7
% and 15% water glass (a reagent manufactured by Wako Pure Chemical Industries, Ltd.) was prepared in the same manner as in Example 1, and its properties were evaluated. As a result, the pellet strength improved to a falling height of 13 cm, but the burning rate significantly decreased to 26.0 mm/sec.

Next, an embodiment embodying the second invention and a comparative example thereof will be described. (Example 9) Manganese dioxide (trade name “FMH”) was heated at 400°C.
It was fired for 2 hours in an electric furnace under atmospheric pressure. Sodium azide (manufactured by Fujimoto Chemicals Co., Ltd.) 61.2%, the above calcined manganese dioxide 32.8%, bentonite (the above product name "
Kunigel VA", silicon dioxide content 61.2%)6.
After adding an appropriate amount of water/acetone to the composition consisting of 0%,
The mixture was mixed for about 20 minutes using a Shinagawa mixer.

[0041] The mixed wet medicine was strained using a 32-mesh silk net to prepare a granulated medicine having a particle size of about 0.5 mm. After drying this granulated drug, 1.0 g thereof was ignited and burned in a closed container of a calorimeter, model P-202 manufactured by Shimadzu Corporation. Next, the gas after combustion was collected using a 1-liter Tedlar pack manufactured by Sanko Plastic Co., Ltd., and the ammonia gas concentration was measured using a Kitagawa gas detection tube (measurement range 5 to 2
60 ppm).

Next, cylindrical pellets with a diameter of 6 mm and a thickness of 3 mm were prepared from the dried granulated drug using a rotary tablet press. Separately, we also use a special mold and manual hydraulic press machine to make 5mm x 8mm x 50mm.
A strand was prepared. The strength and burning rate of the pellets were measured in the same manner as in Example 1 above. Table 3 shows the results.
Shown below. (Examples 10 to 12) Gas generant compositions were manufactured in the same manner as in Example 9, with the compositions shown in Table 3 below, except that the amount of bentonite added was changed, and each gas generating composition was prepared in the same manner. The properties of the generator composition were evaluated. The results are shown in Table 3. (Comparative Example 9) A gas generating composition was produced in the same manner as in Example 9, except that the fired manganese dioxide was replaced with an unfired product, and its properties were evaluated. The results are shown in Table 3. (Comparative Examples 10 to 12) Except for replacing bentonite with kaolinite (reagent manufactured by Wako Pure Chemical Industries, Ltd., silicon dioxide content 46%),
Gas generant compositions having the compositions shown in Table 3 were produced in the same manner as in Example 9, and the characteristics of each gas generant composition were evaluated. The respective results are shown in Table 3.

[0043]

[Table 3]

As can be seen from the results in Table 3, in Examples 9 to 12, which fall within the scope of the present invention, there was almost no generation of ammonia gas, the pellet strength of the gas generating composition was high, and the burning rate was also high. Retained. On the other hand, when unfired manganese dioxide is used (Comparative Example 9), the concentration of ammonia gas is extremely high at 60 ppm. Moreover, when kaolinite with a low content of silicon dioxide is used (Comparative Examples 10 and 11), the pellet strength decreases and the combustion rate also decreases slightly. Furthermore, when no clay material is blended (Comparative Example 12), the pellet strength decreases. (Example 13) The same manganese dioxide used in Example 9 was
It was fired for 4 hours in an electric furnace at 50°C and atmospheric pressure. Barium azide (BaN6, reagent manufactured by Wako Pure Chemical Industries, Ltd.) 66
．． 9%, the above calcined manganese dioxide 27.1%, montmorillonite (manufactured by Kunimine Kogyo Co., Ltd., trade name "Kunipier F", silicon dioxide content 59.7%) 6.0
%, a gas generating composition was produced in the same manner as in Example 9, and its properties were evaluated. The results are shown in Table 4. (Examples 14 to 16) Gas generant compositions were manufactured in the same manner as in Example 9 with the compositions shown in Table 4, except that the amount of montmorillonite added was changed. Characteristics were evaluated. The results are shown in Table 4. (Comparative Example 13) A gas generating composition was produced in the same manner as in Example 9, with the composition shown in Table 4, except that the fired manganese dioxide was replaced with an unfired product, and its characteristics were evaluated. The results are shown in Table 4. (Comparative Example 14) Except for replacing montmorillonite with kaolinite,
A gas generating agent composition having the composition shown in Table 4 was produced in the same manner as in Example 9, and its properties were evaluated. The results are shown in Table 4. (Comparative Examples 15 and 16) Gas generant compositions having the compositions shown in Table 4 were manufactured in the same manner as in Example 9, and the characteristics of each gas generant composition were evaluated. The results are shown in Table 4.

[0045]

[Table 4]

As shown in Table 4, in Examples 13 to 16, which fall within the scope of the second invention, there was almost no generation of ammonia gas, the pellet strength of the gas generating composition was high, and the burning rate was also low. held high. On the other hand, when unfired manganese dioxide is used (Comparative Example 13), the concentration of ammonia gas is extremely high at 40 ppm. Furthermore, when using kaolinite with a low content of silicon dioxide (Comparative Example 14), the pellet strength decreased and
The combustion rate also decreases slightly. Furthermore, when the blending ratio of kaolinite is outside the range of the second invention (Comparative Examples 15 and 1
6) The pellet strength is reduced or the burning rate is reduced. (Comparative Example 17) Manganese dioxide (trade name “FMH”) was heated at 200°C.
It was fired for 4 hours in an electric furnace under atmospheric pressure. Using this calcined manganese dioxide, a gas generating composition was produced with the same composition and method as in Example 9, and its properties were evaluated using the same method. As a result, the pellet strength was 9cm,
The strand burning rate showed a relatively good result of 44.3 mm/sec, but the ammonia gas concentration was 50 pp.
It was m. (Comparative Example 18) Manganese dioxide (trade name “FMH”) was heated at 550°C.
It was fired for 2 hours in an electric furnace under atmospheric pressure. Using this calcined manganese dioxide, a gas generating composition was produced with the same composition and method as in Example 9, and its properties were evaluated using the same method. As a result, the pellet strength was 9cm,
Although the ammonia gas concentration showed relatively good results with less than 5 ppm, the strand burning speed was 26.2 mm/s.
It showed a low value of ec.

[0047]

Effects of the Invention: Since the gas generating composition of the first invention does not use an organic binder, it does not generate harmful components such as carbon monoxide or cyanide, and does not reduce the combustion rate. Furthermore, since it does not contain fibrous substances such as graphite fibers, it has the excellent effect of improving the strength of pellets without reducing workability during pellet production.

[0048] In the second invention, the gas generating composition containing calcined manganese dioxide suppresses the generation of harmful components such as ammonia, and since the clay material is blended, the combustion rate of the gas generating composition is increased. It has the excellent effect that its strength can be improved without reducing its strength, and the gas produced is at a low temperature.

Claims (2)

[Claims] Claim 1: A clay material containing sodium azide and an oxidizing agent as main components and containing 40% by weight or more of silicon dioxide.
A gas generating composition containing 25% by weight. 2. 5 to 20 weight by weight of a clay material whose main components are an azide of an alkali metal or an alkaline earth metal and calcined manganese dioxide calcined in an atmosphere of 250 to 500°C, and which contains 50 wt% or more of silicon dioxide. A gas generating agent composition containing %.