JP4682543B2 - Ignition agent for gas generator - Google Patents

Description

  The present invention relates to an igniting agent used in, for example, a gas generator for inflating an airbag as an occupant protection device or a gas generator for a pretensioner for winding up a seat belt. Is.

  In general, a vehicle such as an automobile is equipped with an airbag or a seat belt in order to protect an occupant from a shock at the time of a collision. The air bag is designed to prevent the passenger from colliding with the passenger by rapidly inflating the bag with gas in order to prevent the passenger from strongly hitting a hard part inside the vehicle such as the handle or the front glass when the vehicle collides at high speed. . In recent years, as a gas generating agent used in airbags, research and development of a non-azide gas generating agent that has little adverse effect on passengers has been made in various fields instead of a gas generating agent mainly composed of sodium azide. .

  Preferred non-azide gas generating agents are those having a gasification rate of 70% or more and a combustion rate of 8.0 mm / second or more (under a condition of being pressurized to 7 MPa by nitrogen gas). . A high gasification rate means that the amount of the gas generating agent filled in the gas generator or the like can be reduced, and the occupant protection device can be reduced in size and weight. Therefore, a non-azide gas generating agent having a gasification rate of 70% or more, preferably 75% or more is demanded.

  On the other hand, the seat belt prevents the occupant from being thrown forward when the vehicle collides at high speed. In recent years, a pretensioner system that winds up the seat belt is further arranged. The pretensioner system pulls in the seat belt instantaneously, restrains the occupant's body, and prevents it from being thrown forward. It has a structure. In such a pretensioner system, since the seat belt needs to be pulled in instantaneously, the combustion gas of the gas generating agent is used as power. That is, the piston in the cylinder is instantaneously moved by the combustion gas of the gas generating agent, and the device for pulling the seat belt connected to one end of the piston or the belt pulling gear is instantaneously rotated. This is a device for retracting a seat belt connected to a gear.

  Conventionally, as this type of non-azide gas generating agent, a gas generating agent mainly composed of nitrocellulose has been used. A gas generating agent mainly composed of nitrocellulose has a very high gasification rate, but on the other hand, it generates a large amount of carbon monoxide in the product gas after combustion, and heat resistance at high temperatures. There were problems such as lacking. Therefore, at present, there is a demand for a non-azide-based gas generating agent that does not substantially generate carbon monoxide while maintaining a high gasification rate, and further has excellent heat resistance.

Based on the above, the oxidizing agent used in the gas generating agent for occupant protection devices such as airbags and pretensioners is ammonium, alkali metal or alkaline earth metal chlorate that can achieve a high gasification rate, excess Chlorates, nitrates or nitrites are mainly used. Specifically, a composition in which an oxidizing agent is ammonium perchlorate and a fuel is starch is known as a gas generating agent (see, for example, Patent Document 1). A gas generating agent in which the oxidizing agent is ammonium nitrate and the fuel is polyacrylamide is also known (see, for example, Patent Document 2). Furthermore, a gas generating agent in which the oxidizing agent is ammonium nitrate and the fuel is 5-aminotetrazole is known (see, for example, Patent Document 3). All of these non-azide gas generating agents have a high gasification rate and high heat resistance, and further have an advantage that carbon monoxide is not contained in the product gas after combustion.
JP 2001-2488 A (pages 2 and 7) JP 2000-103691 A (page 2, page 5) JP 10-130086 (page 2, page 4)

  The conventional gas generators for pretensioners and airbags use oxygen balance, oxidizer types, etc. in order to achieve a high gasification rate without containing carbon monoxide in the product gas after combustion. Is set to a predetermined condition. However, gas generants, particularly non-azide gas generants, tend to have lower ignitability and combustibility as the gasification rate is increased. Therefore, the conventional non-azide gas generating agents for pretensioners and airbags have a problem that the gasification rate is high, but the ignitability is extremely poor and the combustibility is low.

  The present invention has been made paying attention to such problems existing in the prior art. The object is to provide an igniter for a gas generator that can improve the ignitability and flammability of a non-azide gas generant while maintaining a high gasification rate.

In order to achieve the above object, an igniter for a gas generator according to a first aspect of the present invention includes a combustion chamber in which a gas generating agent that generates gas by combustion is accommodated, and ignition by energization to burn the gas generating agent. An ignition agent used in a gas generator for an occupant protection device for a vehicle including an ignition unit that expresses a function, and stored in the combustion chamber or the ignition unit, wherein the gas generating agent is ammonium nitrate or perchlorine as an oxidant. It is a non-azide gas generant containing ammonium acid, the igniter contains potassium perchlorate as an oxidant, and the ignition rate is faster than the non-azide gas generant. is, the occupant protection device for a gas generator, which is characterized in that the gas generated in the combustion chamber is configured gas generator for a pretensioner to draw the seat belt A.

  The igniter for the gas generator according to the second invention is the igniter for the gas generator according to the first invention, wherein the combustion speed is defined by the arrival time from the start of energization to the ignition part to the maximum pressure by the gas generated in the combustion chamber. The arrival time is configured to be shorter than the arrival time of the non-azide gas generating agent.

  The igniting agent for the gas generator of the third invention is the igniting agent for the gas generator according to the second invention, wherein the arrival time of the igniting agent is charged so that the igniting agent or the gas generating agent is loaded in the sealed container at a loading density of 0.059 g / ml. In the combustion test, the time required for the ignition part to reach the maximum pressure due to the gas generated in the sealed container is determined by the arrival time, and the arrival time is 5 to 20 milliseconds for the igniting agent. It is 25-100 milliseconds for the agent.

According to the present invention, the following effects can be exhibited.
The igniting agent for the gas generator according to the first aspect of the invention is configured such that the burning rate of the igniting agent is higher than the burning rate of the non-azide gas generating agent. Therefore, the ignition agent is ignited faster than the non-azide gas generating agent, and the propagation of the flame and the propagation of the combustion during the combustion is faster, so that the combustion of the non-azide gas generating agent can proceed rapidly. Therefore, the ignitability and combustibility of the non-azide gas generating agent can be improved while maintaining a high gasification rate.

  In the igniting agent of the second or third invention, the combustion speed is defined by the arrival time from the start of energization to the ignition part to the maximum pressure by the gas generated in the combustion chamber, and the arrival time of the igniting agent is a non-azide gas generating agent. It is comprised so that it may become shorter than the arrival time of. Therefore, the effect of the first invention can be improved.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
First, a pretensioner gas generator and an air bag gas generator that constitute an occupant protection device to which the ignition agent of this embodiment is applied will be described.

First, the pretensioner gas generator will be described.
A pretensioner is disposed next to the seat in the automobile interior. As shown in FIGS. 2A and 2B, a pretensioner gas generator 12 is attached to the upper surface of the main body 11 constituting the pretensioner 10. A cylinder 13 is connected to the rear portion of the pretensioner gas generator 12 (on the left side of FIG. 2A). A rotating drum 14 is rotatably supported at the rear portion of the main body 11, and one end of a seat belt 15 is wound around the lower end of the piston rod 16. A piston 17 is fixed to an intermediate portion of the piston rod 16 located in the cylinder 13 and is raised by the gas generated from the pretensioner gas generator 12. A cylindrical stopper 18 whose diameter is reduced toward the upper part is fixed at a position above the piston rod 16 in the cylinder 13 so as to restrict the ascent of the piston 17 at a predetermined position. The upper end of the cylinder 13 is covered with a covered cylindrical cap 19.

  As shown in FIG. 1, the pretensioner gas generator 12 is configured by attaching a lidded cylindrical loading container 21 to one end of a holder 20 thereof. An electric igniter 22 as an igniter is supported at the center position of one end of the holder 20. A lead wire 23 is connected to the bottom of the electric igniter 22 so that the electric igniter 22 is energized and ignited. The inside of the loading container 21 becomes a combustion chamber 24. In the combustion chamber 24, a gas generating agent 25 for a pretensioner having a cylindrical shape and a columnar ignition agent 26 formed smaller than that are mixed. It is loaded. A plurality of grooves 27 extending radially are formed in the center of the lid portion of the loading container 21. When the electric igniter 22 is ignited, the igniting agent 26 and the gas generating agent 25 in the combustion chamber 24 are ignited and burned, and the generated gas is released into the cylinder 13 through the portion of the weak groove 27. The piston 17 is moved to retract the seat belt 15 by the rotation of the rotary drum 14.

Next, in order to compare with the gas generator for pretensioners, the gas generator for airbags will be described. As shown in FIG. 4, the gas generator for airbags 30 is formed in a cylindrical shape at the center. The ignition part 31 provided and the combustion chamber 32 formed concentrically on the outer periphery thereof are provided. The ignition unit 31 includes an electric igniter 34 and an igniting agent 35 disposed on the electric igniter 34. When the electric igniter 34 is energized, the igniting agent 35 is ignited. A partition wall 36 is provided between the ignition unit 31 and the combustion chamber 32, and a plurality of vent holes 37 are formed in the partition wall 36, and a flame caused by the ignition powder 35 is guided from the ignition unit 31 to the combustion chamber 32. It is like that.

  The combustion chamber 32 is charged with a gas generating agent 38 having a cylindrical shape and a cylindrical igniting agent 39 having a smaller size. Although it is possible to arrange the igniting agent 39 in the gap 28 of the ignition unit 31, it is preferable to load the ignition agent 39 into the combustion chamber 32 as described above. Further, a concentric filter 42 is disposed on the outer peripheral portion of the combustion chamber 32 to cool the generated gas and collect the solid combustion residue by filtration. A plurality of gas ejection holes 44 are formed in the peripheral wall 43 of the combustion chamber 32 so that the gas cooled by the filter 42 is ejected into the airbag 45 and the airbag 45 is inflated.

  As the gas generating agents 25 and 38, non-azide gas generating agents not containing an azide compound such as sodium azide are used. As the igniting agents 26 and 39, those whose burning rate is faster than the burning rate of the non-azide gas generating agent are used. The igniting agents 26 and 39 are used in the combustion chambers 24 and 32 together with a non-azide gas generating agent. As a form thereof, in addition to the form in which both are mixed and used as described above, the igniting agents 26 and 39 are arranged in the vicinity of the ignition unit, and the gas generating agents 25 and 38 are arranged in a position away from the ignition unit. Forms are also adopted.

  The non-azide gas generating agent plays a role of inflating the air bag 45 by the combustion gas generated when combusting and momentarily moving the piston 17 for the pretensioner 10. Therefore, the combustion chambers 24 and 32 are loaded with a non-azide gas generating agent sufficient to obtain a sufficient combustion gas. As a result, if harmful gases such as carbon monoxide, nitrogen oxides, and hydrogen chloride are generated in the combustion gas, the human body may be adversely affected. It is desired to increase the gasification rate. In addition, the operating time, i.e., the burning rate, is determined according to the application used, and must have such a burning rate.

  On the other hand, the igniting agents 26 and 39 are used in combination with a non-azide gas generating agent having poor ignitability and flammability to improve the ignitability and combustibility of the non-azide gas generating agent. Therefore, the igniting agents 26 and 39 must be more ignitable than non-azide gas generating agents, and must be more flammable than non-azide gas generating agents. Further, since the igniting agents 26 and 39 are used in a smaller amount than the non-azide gas generating agent, it is not necessary to consider the gasification rate and the combustion gas component.

  The combustion speed is defined by the arrival time from the start of energization to the ignition part to the maximum pressure due to the gas generated in the combustion chambers 24 and 32. The arrival times of the igniting agents 26 and 39 are set to be shorter than the arrival time of the non-azide gas generating agent. Since the non-azide gas generating agent has poor ignitability, the flame generated from the ignition part is ignited by arranging the non-azide gas generating agent and the igniting agents 26 and 39 having excellent ignitability. It is immediately transmitted to the agents 26 and 39, and the igniting agents 26 and 39 are ignited. At the same time, the flame generated by the combustion of the igniting agent instantaneously burns the non-azide gas generating agent, which is considered to improve the ignitability and combustibility of the non-azide gas generating agent.

  The arrival time of the igniting agents 26 and 39 is determined in the sealed container from the start of energization to the ignition part in the combustion test when the igniting agent or the gas generating agent is loaded in the sealed container so as to have a loading density of 0.059 g / ml. This is determined by the time required to reach the maximum pressure due to the generated gas. The specific arrival time measurement is performed by a sealed bomb combustion test described later, and the arrival time is 5 to 20 milliseconds for the igniting agent and 25 to 100 milliseconds for the non-azide gas generating agent. It is preferably 10 to 15 milliseconds for the igniting agent, and more preferably 30 to 65 milliseconds for the non-azide gas generating agent.

  If the arrival time of the igniting agents 26 and 39 is less than 5 milliseconds, the gas generation speed becomes too fast, and the igniting agents 26 and 39 burn out instantaneously, so that the ignitability and flammability of the non-azide gas generating agent are improved. It becomes difficult. On the other hand, when the arrival time of the igniting agents 26 and 39 exceeds 20 milliseconds, the gas generation rate becomes too slow and becomes a gas generation rate close to that of the non-azide gas generating agent. It becomes difficult to improve ignitability and flammability. Further, when the arrival time of the non-azide gas generating agent is less than 25 milliseconds, the gas generation speed tends to be too high. On the other hand, when the arrival time of the non-azide-based gas generating agent exceeds 100 milliseconds, the gas generation speed becomes too slow and it is difficult to apply to the pretensioner gas generator 12 and the air bag gas generator 30. It becomes.

Next, the composition of the ignition agents 26 and 39 will be described. The igniting agents 26 and 39 are composed of a plasticizer, a aging stabilizer, a slag forming agent, and the like, in addition to the oxidizing agent and the fuel. As the oxidizing agent, potassium perchlorate is used as an essential component, but other oxidizing agents are not particularly limited, and any of them can be used. Specific examples of the oxidizing agent containing potassium perchlorate include nitrates, nitrites, oxohalogenates, and the like. Examples of the nitrate include ammonium salts such as ammonium nitrate, alkali metal salts such as sodium nitrate and potassium nitrate, and alkaline earth metal salts such as barium nitrate and strontium nitrate. Examples of the nitrite include alkali metal salts such as sodium nitrite and potassium nitrite, and alkaline earth metal salts such as barium nitrite. Examples of oxohalogenates include halogenates and perhalogenates.

  Specific examples of the halogen acid salt include alkali metal salts such as potassium chlorate and sodium chlorate, alkaline earth metal salts such as barium chlorate and calcium chlorate, and ammonium salts such as ammonium chlorate. Specific examples of the perhalogenate include alkali metal salts such as potassium perchlorate and sodium perchlorate, alkaline earth metal salts such as barium perchlorate and calcium perchlorate, and ammonium such as ammonium perchlorate. Salt.

  Among these oxidizing agents, in view of combustibility and ignitability, potassium salts, specifically potassium nitrate, potassium nitrite, potassium chlorate and potassium perchlorate are preferable, and potassium perchlorate is particularly preferable. In view of the gasification rate, ammonium salts, specifically ammonium nitrate, ammonium chlorate, and ammonium perchlorate are preferable, and ammonium perchlorate is particularly preferable. Perchlorate, such as ammonium perchlorate, generates hydrogen chloride when burned, so it is recommended to mix chlorine scavengers such as alkali metal salts of nitric acid such as sodium nitrate and potassium nitrate to prevent the release of hydrogen chloride. Is preferred.

  The blending amount of perchlorate and chlorine scavenger reduces the amount of hydrogen chloride generated in the generated gas and improves the amount of gas generated. The scavenger is preferably 1.0 to 1.2 mol, more preferably 1.0 to 1.1 mol, and particularly preferably 1.0 to 1.05 mol. When the amount of chlorine scavenger is less than 1.0 mol, hydrogen chloride generated from perchlorate cannot be completely captured and tends to be released into the vehicle cabin. If it exceeds, the gas generation amount tends to decrease.

  The oxidant used as the igniting agent 26, 39 does not contain a chlorine scavenger, only perchlorate such as ammonium perchlorate, and the igniting agent 26 as the oxidant used for the non-azide gas generating agent. , 39 can be blended with a chlorine scavenger capable of collecting hydrogen chloride generated from 39. If it is a combination of these ignition agents 26 and 39 and a non-azide type gas generating agent, it can prevent generating hydrogen chloride after combustion.

  The shape of the oxidizing agent is preferably a powder from the viewpoint of mixing properties and combustibility. The average particle size of the powder is preferably 1 to 200 μm. If it is less than 1 μm, the production tends to be difficult. On the other hand, if the average particle size exceeds 200 μm, clogging tends to occur during the production and the production cannot be performed, and the ignitability is poor and the combustion rate tends to be slow. Further, in consideration of manufacturability and combustion performance of the igniting agents 26 and 39, it is more preferably 1 to 100 μm, and particularly preferably 1 to 50 μm.

  The blending amount of the oxidizing agent is preferably 68 to 98% by mass, more preferably 78 to 96% by mass, and particularly preferably 82 to 95% by mass with respect to the total mass of the oxidizing agent and the fuel. When the blending amount of the oxidizing agent is less than 68% by mass, the ignitability of the igniting agents 26 and 39 tends to be poor and the combustion speed tends to be slow. Moreover, when the compounding quantity of an oxidizing agent exceeds 98 mass%, it exists in the tendency for the mechanical physical properties of the ignition agents 26 and 39 to fall.

  Next, fuel will be described. It does not specifically limit as a fuel used for the ignition agents 26 and 39, All can be used. Specific examples include polymer binders, powdered microcrystalline carbon, nitrogen-containing compounds, and the like. The polymer binder has both a function as a binder for shaping a powdery component into a granular form and a function as a fuel.

  Specific examples of such a polymer binder include, for example, nitrocellulose, cellulose acetate, carboxymethylcellulose and salts thereof, carboxymethylethylcellulose, hydroxymethylcellulose, hydroxyethylcellulose. Cellulose such as hydroxypropyl cellulose, microcrystalline cellulose, cellulose acetate butyrate, methyl cellulose, ethyl cellulose, cellulose acetate nitrate, cellulose nitrate carboxymethyl ether, etc. Polymers such as polyvinyl alcohol, polyvinyl butyral, polyvinyl ether, polyvinyl acetal, polyvinyl formal, polyvinyl pyrrolidone, polyvinyl caprolactam, copolymers of polyvinyl pyrrolidone and polyvinyl caprolactam, carboxyvinyl polymer, etc. Polybi Polyester polymers; Polyester polymers such as polyester synthetic fibers, polyethylene terephthalate, unsaturated polyester resins; Polyurethane polymers such as urethane resins; Polyether polymers such as polypropylene oxide, polyphenylene oxide, and polyetherimide ; Poly (meth) acrylic acid derivatives such as polyacrylamide, polyacrylic acid hydrazide, sodium polyacrylate, polyacrylate, polymethacrylate, polymethyl methacrylate; polyurethane elastomer (trade name: Pandex, manufactured by Dainippon Ink Co., Ltd.) Thermoplastic elastomers such as polyester elastomer (trade name: Perprene, manufactured by Toyobo Co., Ltd.), polystyrene elastomer (trade name: manufactured by Clayton, Shell Japan Co., Ltd.); nylon 6, nylon 66, Iron 610, nylon 612, nylon 11, nylon 12, nylon 46, polyamides such as copolymerized polyamide, methoxymethylated polyamide, alcohol-soluble polyamide; glycidyl azide polymer, 3,3-bis (azidomethyl) oxetane, 3-azidomethyl Energetic compound binders such as -3-methyloxetane and 3-nitratemethyl-3-methyloxetane; polysaccharides such as guar gum, soluble starch, pectin, chitin and derivatives thereof; acrylic rubber, isoprene rubber, urethane rubber , Rubbers such as silicon rubber, Viton (registered trademark of DuPont), butadiene rubber, butyl rubber, nitrile butadiene rubber, nitrile butadiene rubber, and fluorine rubber. At least one of these polymer binders is appropriately selected and used. Among these polymer binders, cellulose-based binders such as cellulose acetate, cellulose acetate butyrate or ethyl cellulose having a high ability to shape oxidants and fuel powdery constituents are preferable.

  Next, powdery microcrystalline carbon will be described. Examples of the powdered microcrystalline carbon include activated carbon, charcoal, coke, animal charcoal, bone charcoal, and bituminous charcoal. Powdered microcrystalline carbon means an aggregate of graphite-based microcrystals that lack structural integrity compared to graphite. That is, two-dimensionally, similar to graphite, the net planes are stacked in parallel, equally spaced, but the layer planes are not perfectly oriented in the vertical direction, and the layers are stacked irregularly, A carbon hexagon consisting of a spatial lattice with irregular cross-connections, such as those having a distortion on the graphite surface. Among these powdery microcrystalline carbons, activated carbon and charcoal having high reactivity with an oxidizing agent are preferable.

  The shape of the powdered microcrystalline carbon is preferably a powder from the viewpoint of mixing and flammability. The average particle diameter is preferably 0.1 to 200 μm. When it is less than 0.1 μm, it tends to be difficult to form the igniting agents 26 and 39 in a granular form. On the other hand, if the average particle diameter exceeds 200 μm, clogging occurs during the production of the igniting agents 26 and 39, making the production difficult, and the ignitability is poor, and the combustion rate tends to be slow.

Furthermore, considering the mechanical properties and combustion performance of the igniting agents 26 and 39, the average particle size of the powdered microcrystalline carbon is more preferably 1 to 100 μm, and particularly preferably 1 to 50 μm. In addition, the specific surface area of the powdered microcrystalline carbon is preferably 5 to 1600 m ² / g. When the specific surface area of the powdered microcrystalline carbon is less than 5 m ² / g, the burning rates of the igniting agents 26 and 39 tend to be slow. On the other hand, when the specific surface area of the powdered microcrystalline carbon exceeds 1600 m ² / g, the productivity of the powdered microcrystalline carbon tends to deteriorate. And more considering mechanical properties and combustion performance of the firing agents 26, 39, a specific surface area is more preferably from 10~1500m ² / g, particularly preferably 50~1300m ² / g.

  Next, the nitrogen-containing compound will be described. Examples of nitrogen-containing compounds include nitramine compounds, guanidine derivatives, tetrazole derivatives, bitetrazole derivatives, triazole derivatives, hydrazine derivatives, triazine derivatives, amino acid derivatives, acid amide derivatives, and the like. Specific examples of such nitrogen-containing compounds include trimethylenetrinitroamine (RDX), tetramethylenetetranitroamine (HMX), pentaerythritol tetranitrate (PETN), nitroguanidine (NQ), Examples thereof include triaminoguanidine nitrate (TAGN), 5-aminotetrazole, dinitroamelin, azodicarbonamide, hydrazine nitrate and the like.

  Moreover, it is preferable that the average particle diameter of a nitrogen-containing compound is 1-200 micrometers. If this average particle diameter is less than 1 μm, it tends to be difficult to form the igniting agents 26 and 39. On the other hand, if the average particle diameter exceeds 200 μm, clogging occurs during production, making the production difficult, and the ignitability is poor, and the combustion rate tends to be slow. Further, considering the mechanical properties and combustion performance, the average particle size is more preferably 1 to 100 μm, and particularly preferably 1 to 30 μm.

  The blending amount of the fuel is preferably 2 to 32% by mass, more preferably 4 to 22% by mass, and particularly preferably 5 to 18% by mass with respect to the total mass of the oxidant and the fuel. When the blending amount of the fuel is less than 2% by mass, the mechanical properties of the igniting agents 26 and 39 tend to decrease, and the gas generation amount tends to decrease. When the blending amount of the fuel exceeds 32% by mass, the ignitability of the igniting agents 26 and 39 tends to be poor and the combustion speed tends to be slow, so that the function as the igniting agents 26 and 39 may not be performed.

  Further, the igniting agents 26 and 39 can be plasticized to impart plasticity and improve moldability. Any plasticizer that is compatible with the binder can be used. For example, fatty acid ester plasticizers such as acetyl tributyl citrate and acetyl triethyl citrate; phthalic acid diester plasticizers such as dibutyl phthalate, dimethyl phthalate and diethyl phthalate; phosphate esters, triacetin, trimethylol ethane trinitrate, diethylene glycol Nitro plasticizers such as -rudinite, triethylene glycol dinitrate, nitroglycerin, bis-2,2-dinitropropylacetate / formal; glycidyl azide plasticizer and the like.

  The blending amount of the plasticizer is preferably 15% by mass or less in the ignition agent. When the addition amount of the plasticizer exceeds 15% by mass, the effect as a plasticizer becomes great, but since the blending ratio of other components decreases, the combustibility and ignitability tend to deteriorate. Furthermore, if combustibility and ignitability are considered, the blending amount of the plasticizer is more preferably 1 to 12% by mass, and particularly preferably 1 to 8% by mass.

  In addition, an aging stabilizer can be blended with the ignition agents 26 and 39 in order to improve the stability over a long period of time. As such a aging stabilizer, all can be used as long as the aging stability can be improved. For example, diphenylurea derivatives such as diphenylurea, methyldiphenylurea, ethyldiphenylurea, diethyldiphenylurea, dimethyldiphenylurea, methylethyldiphenylurea; diphenylamine derivatives such as diphenylamine, 2-nitrodiphenylamine; ethylphenylurethane, methylphenylurethane, etc. And phenylurethane derivatives; diphenylurethane derivatives such as diphenylurethane; and resorcinol. Of these, diphenylamine and diethyldiphenylurea are particularly preferred in that the igniting agents 26 and 39 are excellent in stability over time and ignitability in the early stage of combustion.

  The blending amount of the aging stabilizer is preferably 10% by mass or less in the ignition agent. If it exceeds 10% by mass, the effect as a stabilizer will be great, but since the blending ratio of other components will decrease, the combustibility and ignitability will tend to deteriorate. In view of improving the temporal stability of the igniting agents 26 and 39 and further considering the combustibility and ignitability, 0.2 to 5% by mass is more preferable, and 0.2 to 3% by mass is particularly preferable.

  In addition, the igniting agents 26 and 39 are mixed with a slag forming agent in order to suppress the release of the alkali metal or alkaline earth metal oxide generated by the decomposition of the oxidizer or the like as mist to the outside of the gas generator. Can do. Specific examples of the slag forming agent include, for example, silica, alumina, acid clay, talc, mica, molybdenum disulfide, and the like. Among these, silica, alumina, and acid clay are preferable. The blending amount of the slag forming agent is preferably 10% by mass or less in the ignition agents 26 and 39. When the addition amount of the slag forming agent exceeds 10% by mass, the effect as the slag forming agent becomes great, but the combustibility and ignitability tend to be deteriorated because the blending ratio of other compositions is lowered. Considering the combustibility and ignitability, the blending amount of the slag forming agent is more preferably 1 to 5% by mass, and particularly preferably 1 to 3% by mass.

  A preferred composition for the igniting agents 26 and 39 is a combination of an oxohalogenic acid alkali metal salt as an oxidant, a cellulose polymer binder as a fuel, and a fatty acid ester as a plasticizer. Specifically, it is a combination of potassium perchlorate as an oxidizing agent, cellulose acetate butyrate as a fuel, and acetyltributyl citrate as a plasticizer. Since this composition is excellent in ignitability and combustibility, and further excellent in heat resistance and mechanical properties, it is preferable as the igniting agent 26, 39.

  A combination of an ammonium salt of oxohalogenic acid as an oxidizing agent, a cellulose polymer binder as a fuel, and a fatty acid ester as a plasticizer is also preferable. Specifically, a combination of ammonium perchlorate as an oxidizing agent, cellulose acetate butyrate as a fuel, and acetyltributyl citrate as a plasticizer. This composition is excellent as a igniting agent because it is excellent in combustibility and also excellent in heat resistance and mechanical properties.

  As described above, since the igniting agents 26 and 39 are required to have excellent ignitability and combustibility, the oxygen amount in the igniting agents 26 and 39 is excessive (when the oxygen balance is positive). Is desirable.

Next, the composition of the non-azide gas generating agent will be described.
The non-azide gas generating agent is composed of a plasticizer, a aging stabilizer, a slag forming agent and the like in addition to the oxidant and the fuel. The oxidizing agent contains ammonium nitrate or ammonium perchlorate as an essential component, but other oxidizing agents are not particularly limited, and oxidizing agents used for the ignition agents 26 and 39 can also be used. The oxidizing agent containing ammonium nitrate or ammonium perchlorate will be described. In view of the gasification rate, ammonium salts, specifically ammonium nitrate, ammonium chlorate, and ammonium perchlorate are preferable, and ammonium nitrate is particularly preferable. The shape of the oxidizing agent is preferably a powder from the viewpoint of mixing properties and combustibility. The average particle size of the powder is preferably in the range of 1 to 500 μm. When the average particle size is less than 1 μm, it tends to be difficult to produce a non-azide gas generating agent. On the other hand, when the average particle diameter exceeds 500 μm, the mechanical properties of the molded article are deteriorated, and the burning rate tends to be lowered. Further, considering the mechanical properties and combustion performance of the non-azide gas generating agent, the average particle size is more preferably 1 to 200 μm, and particularly preferably 1 to 100 μm.

  The blending amount of the oxidizing agent is preferably 58 to 97% by mass, more preferably 75 to 95% by mass, and particularly preferably 78 to 93% by mass with respect to the total mass of the oxidizing agent and the fuel. When the blending amount of the oxidizing agent is less than 58% by mass, a large amount of carbon monoxide tends to be generated in the generated gas. Moreover, when the compounding quantity of an oxidizing agent exceeds 97 mass%, it exists in the tendency for the mechanical physical property of a non-azide type | system | group gas generating agent to fall, and for a combustion rate to also fall. If the amount of oxygen in the non-azide gas generating agent is insufficient (when the oxygen balance is negative), harmful carbon monoxide is generated due to incomplete combustion during combustion.

  On the other hand, when the amount of oxygen in the non-azide gas generating agent is excessive (when the oxygen balance is positive), harmful nitrogen dioxide and the like are generated when burned. Therefore, in order to suppress the generation of harmful substances, the blending ratio of the oxidant and fuel in the non-azide gas generating agent is adjusted so that the oxygen amount in the non-azide gas generating agent does not become excessive or insufficient (oxygen). It is desirable that the balance be in the range of ± 0). From this viewpoint, the blending amount of the oxidizing agent in the non-azide gas generating agent is substantially set.

  Next, fuel will be described. It does not specifically limit as a fuel used for a non-azide type gas generating agent, The fuel used for an ignition agent can also be used. Specific examples include polymer binders, powdered microcrystalline carbon, nitrogen-containing compounds, and the like. Among the polymer binders, cellulose-based binders such as cellulose acetate, cellulose acetate butyrate or ethyl cellulose having a high ability to form oxidant and fuel powdery components are preferable.

  Among powdered microcrystalline carbon, activated carbon and charcoal having high reactivity with an oxidizing agent are preferable. The shape of the powdered microcrystalline carbon is preferably a powder from the viewpoint of mixing and flammability. The average particle diameter is preferably 0.1 to 500 μm. When it is less than 0.1 μm, it tends to be difficult to form the non-azide gas generating agent into a granular form. On the other hand, when the average particle diameter exceeds 500 μm, the burning rate tends to be slow. Further, considering the mechanical properties and combustion performance of the non-azide gas generating agent, the average particle size is more preferably 1 to 200 μm, and particularly preferably 1 to 100 μm.

Furthermore, the specific surface area of the powdered microcrystalline carbon is preferably 5 to 1600 m ² / g. When the specific surface area of the powdered microcrystalline carbon is less than 5 m ² / g, the burning rate of the non-azide gas generating agent tends to be slow. On the other hand, when the specific surface area of the powdered microcrystalline carbon exceeds 1600 m ² / g, the productivity of the powdered microcrystalline carbon tends to deteriorate. And more considering mechanical properties and combustion performance of the non-azide gas generating agent, the specific surface area is more preferably from 10~1500m ² / g, particularly preferably 50~1300m ² / g.

  Among the nitrogen-containing compounds, trimethylenetrinitroamine (RDX), tetramethylenetetranitroamine (HMX), pentaerythritol tetranitrate (PETN), nitroguanidine (NQ), triaminoguanidine nitrate (TAGN), 5-aminotetrazole, dinitroamelin, azodicarbonamide, hydrazine nitrate and the like are preferable.

  Moreover, it is preferable that the average particle diameter of a nitrogen-containing compound is 1-500 micrometers. If the average particle size is less than 1 μm, it tends to be difficult to form the non-azide gas generant into a granular shape, and if the average particle size exceeds 500 μm, the effect of improving the combustion rate tends to be lost. Furthermore, considering the mechanical properties and combustion performance of the non-azide gas generating agent, the average particle size is more preferably 1 to 200 μm, and particularly preferably 1 to 100 μm.

  The blending amount of the fuel is preferably 3 to 42% by mass, more preferably 5 to 25% by mass, and particularly preferably 7 to 22% by mass with respect to the total mass of the oxidant and the fuel. When the blending amount of the fuel is less than 3% by mass, the mechanical properties of the non-azide gas generating agent are lowered, and the gas generation amount tends to be lowered. When the blending amount of the fuel exceeds 42% by mass, a large amount of carbon monoxide tends to be generated in the generated gas.

  Furthermore, a plasticizer can be blended with the non-azide gas generating agent in order to impart plasticity and improve moldability. As such a plasticizer, any plasticizer that is compatible with the binder as well as the ignition agent can be used, and the amount of the plasticizer added is preferably 15% by mass or less in the non-azide gas generating agent. .

  Furthermore, a non-azide gas generating agent can be blended with a time-dependent stabilizer in order to improve the time-dependent stability. As such a aging stabilizer, any substance capable of improving the aging stability as in the case of the igniting agents 26 and 39 can be used. 10 mass% or less is preferable in an agent.

  Furthermore, a non-azide-based gas generating agent is mixed with a slag forming agent in order to suppress release of alkali metal or alkaline earth metal oxide generated by decomposition of an oxidizing agent or the like as mist to the outside of the gas generator. be able to. As such a slag forming agent, any substance capable of forming slag as in the case of the igniting agents 26 and 39 can be used, and the amount of the slag forming agent added is the amount of the non-azide gas generating agent. Is preferably 10% by mass or less.

  A preferred composition as the non-azide gas generating agent is a combination of an ammonium salt of nitric acid as an oxidizing agent, a cellulose polymer binder as a fuel, and a fatty acid ester as a plasticizer. Specifically, a combination of ammonium nitrate as an oxidizing agent, cellulose acetate butyrate as a fuel, and acetyltributyl citrate as a plasticizer. Since this composition has an excellent gasification rate and also has excellent heat resistance and mechanical properties, it is more preferable as a non-azide gas generating agent.

  A combination of an ammonium salt of oxohalogenic acid as an oxidizing agent, an alkali metal salt of nitric acid, a cellulose polymer binder as a fuel, and a fatty acid ester as a plasticizer is also preferable. Specifically, a combination of ammonium perchlorate and sodium nitrate as an oxidizing agent, cellulose acetate butyrate as a fuel, and acetyltributyl citrate as a plasticizer. Since this composition has an excellent gasification rate and also has excellent heat resistance and mechanical properties, it is more preferable as a non-azide gas generating agent.

Next, the blending ratio of the igniting agents 26 and 39 and the non-azide gas generating agent will be described.
The blending ratio of the non-azide gas generating agent and the igniting agents 26 and 39 is preferably adjusted so that the non-azide gas generating agent is 60 to 98% by mass and the igniting agents 26 and 39 are adjusted to 2 to 40% by mass. . Further, when used in the pretensioner 10, the non-azide gas generating agent is 60 to 95% by mass in consideration of the efficiency of improving the ignitability and combustibility of the non-azide gas generating agent. Is more preferably 5 to 40% by mass. Further, in consideration of the gasification rate and the loadability in the gas generator, it is particularly preferable that the non-azide gas generating agent is 80 to 95% by mass and the igniting agents 26 and 39 are 5 to 20% by mass. .

  When used for the airbag 45, the non-azide gas generating agent is more preferably 60 to 85% by mass, the igniting agents 26 and 39 are more preferably 15 to 40% by mass, and the non-azide gas generating agent is 70% by mass. It is particularly preferable that the igniting agents 26 and 39 are 15 to 30% by mass at ˜85% by mass. When the blending ratio of the igniting agents 26 and 39 is less than 2% by mass, the ignitability of the igniting agents 26 and 39 cannot be sufficiently exerted, and it is difficult to improve the ignitability and combustibility of the non-azide gas generating agent. It becomes. When the blending ratio of the igniting agents 26 and 39 exceeds 40% by mass, the gas generation rate tends to be too high and the required value tends not to be satisfied, and the gasification rate tends to decrease.

  When the igniting agents 26, 39 and the non-azide gas generating agent are used in combination, the combustion rate of the igniting agents 26, 39 must be higher than that of the non-azide gas generating agent. This is because the ignitability and flammability of the non-azide gas generant cannot be improved even if an igniter having a slower combustion rate than the non-azide gas generant is used. In addition, when using together the igniting agents 26 and 39 obtained from the same raw material and the non-azide gas generating agent, by changing the particle size or adjusting the blending ratio of the oxidizing agent and the fuel, It is necessary to make the burning rate of the ignition agents 26 and 39 faster than the burning rate of the non-azide gas generating agent.

  The igniting agents 26 and 39 are characterized in that they are used in combination with a non-azide gas generating agent. The most effective effect as the igniting agents 26 and 39 is that the non-oxidizing agent is an ammonium oxyacid salt. This is a case of using together with an azide-based gas generating agent. This is because non-azide-based gas generants that use ammonium oxyacid salts as oxidizing agents have high gasification rates, but are extremely poor in ignitability and combustibility, and the gas generants alone satisfy the requirements for combustion performance. This is because the use of an igniting agent is essential. Such igniting agents 26 and 39 are required to have a higher gas generation speed than that of the airbag 45, and the pretensioner 10 is required to have a linear combustion curve from the start of energization to the maximum pressure. More preferably, it is used.

  Next, the shape of the igniting agents 26 and 39 will be described. The shape of the igniting agents 26 and 39 is not particularly limited, and any shape can be used as long as it is granular or powdery and can function as the igniting agents 26 and 39. More specifically, for example, shapes such as a non-perforated cylindrical shape, a perforated cylindrical shape, a perforated hexagonal shape, a perforated irregular shape, and the like can be given. Here, the granular shape does not necessarily have to be formed into a regular shape such as a spherical shape or a cylindrical shape, and may have an irregular shape with a rough surface or a distorted shape.

Next, a method for manufacturing the igniting agents 26 and 39 will be described.
In general, when molding into granules by an extrusion molding method, first, a predetermined amount of fuel such as an oxidizer and a polymer binder and, if necessary, a plasticizer, a stabilizer with time, and a slag former are measured. Thereafter, water or an organic solvent is added to prepare a uniform mixture in a kneader. Then, the uniformly mixed mixture is loaded into an extrusion apparatus, a predetermined pressure is applied, the mixture is extruded through a hole in a die, and then cut to form particles of a predetermined size.

  As the igniting agents 26 and 39 whose time from the start of energization to the maximum pressure to the maximum pressure is adjusted to 5 to 20 milliseconds, non-porous with an outer diameter of 0.1 to 5 mm and a length of about 0.1 to 5 mm A cylindrical shape having a cylindrical shape with an outer diameter of 0.3 to 5 mm, an inner diameter of 0.1 to 4.9 mm, a length of 0.1 to 5 mm, and a thickness of about 0.1 to 3 mm is generally used. The

  In general, when forming into granules by granulation method, first add a predetermined amount of oxidizer, fuel, water or organic solvent, if necessary, plasticizer, aging stabilizer, slag forming agent, etc. in the blender. Prepare a homogeneous mixture. Thereafter, granulation and drying are performed to form a predetermined shape and size. As the igniting agents 26 and 39 whose arrival time from the start of energization to the maximum pressure is 5 to 20 milliseconds, granular materials having an outer diameter of 0.1 to 5 mm and a length of 0.1 to 5 mm are generally used. The

The above-mentioned closed bomb combustion test was conducted by the following method.
First, the sealed bomb combustion test apparatus will be described. As shown in FIG. 3, a cylinder-shaped combustion space 51 having a volume of 70 ml is provided in the bomb body 50, and the gas generating agents 25 and 38 or the ignition agents 26 and 39 are loaded in the combustion space 51. . The volume of the combustion space 51 is calculated by subtracting the volume of a part of the plug body 52 from the volume of a cylindrical body having a diameter of 35 mm and a depth of 75 mm. One end of the bomb body 50 is provided with a plug 52 for loading or sealing the gas generating agent 25, 38 or the igniting agent 26, 39 in the combustion space 51, and the plug body 52 is detachable by a bolt 53. ing. Similarly, an ignition device 56 is connected to one end side of the bomb main body 50 via a connection wiring 54, and the connection wiring 55 is connected to the bomb main body 50.

  A pair of electrodes 57, 58 are attached to the inner end surface of the plug body 52 in the combustion space 51, the one connection wiring 54 is connected to one electrode 57, and the other electrode 58 is connected to the bomb body 50. Has been. An ignition ball (with boron glass 0.5 g) 59 is attached to both electrodes 57 and 58 via connecting wires. Then, by operating the ignition device 56, the ignition ball 59 is ignited through the connection wires 54 and 55, the electrodes 57 and 58, etc., and the gas generating agents 25 and 38 or the ignition agents 26 and 39 in the combustion space 51 are ignited. It is designed to burn.

  A gas vent valve 60 is attached to the side surface of the bomb body 50 and communicates with the combustion space 51 via a sampling pipe 61. The gas in the combustion space 51 is sampled from the degassing valve 60, and its combustion characteristics can be evaluated. A pressure transducer 62 is attached to the other end surface of the bomb body 50 and communicates with the combustion space 51 via a communication pipe 63. The pressure converter 62 can determine the arrival time from the start of energization to the maximum pressure.

  Then, the gas generating agents 25 and 38 or the igniting agents 26 and 39 are loaded in the combustion space 51 with the plug body 52 removed. The loading amount loaded at that time was set to a loading density of 0.059 g / ml. Next, the plug 52 is closed, and the gas generating agents 25 and 38 or the igniting agents 26 and 39 in the combustion space 51 are ignited by the ignition device 56. And the relationship between the combustion time at the time of combustion and combustion pressure was measured with the oscilloscope (not shown) via the pressure converter 62, and the arrival time from energization start to the maximum pressure was calculated | required. The time required from the start of energization to the maximum pressure required for the gas generating agent for the air bag is usually 50 to 65 milliseconds, and the time required for the pre-tensioner gas generating agent to reach the maximum pressure is reached. Is usually 15 to 30 milliseconds.

  In the pretensioner gas generator 12, the ignition agent 26 in the combustion chamber 24 is ignited by energization of the electric igniter 22 based on a signal at the time of a vehicle collision or the like, and a non-azide gas. The generating agent 25 is burned, and combustion gas such as nitrogen gas is generated. At this time, since the burning rate of the igniting agent 26 is set to be higher than the burning rate of the gas generating agent 25, the ignition agent 26 is first ignited by the ignition of the electric igniter 22, and the flame is gas generating agent. 25, the gas generating agent 25 burns quickly. In addition, since the igniting agent 26 is disposed in the combustion chamber 24 in a state of being mixed with the gas generating agent 25, the combustion of the gas generating agent 25 based on the ignition of the igniting agent 26 is performed throughout the combustion chamber 24. Proceed evenly.

  The combustion gas generated in the combustion chamber 24 breaks the portion where the groove 27 is formed and is jetted into the cylinder 13 to move the piston 17 together with the piston rod 16. The rotating drum 14 is rotated by the movement of the piston rod 16 and the seat belt 15 is pulled.

  In the air bag gas generator 30, the ignition charge 35 is ignited by energizing the electric igniter 34 based on a signal at the time of a vehicle collision or the like. The flame due to the ignition is propagated to the combustion chamber 32 through the vent hole 37, the igniting agent 39 in the combustion chamber 32 is ignited, and the non-azide gas generating agent 38 is combusted to generate combustion gas. At this time, since the burning rate of the igniting agent 39 is set to be higher than the burning rate of the gas generating agent 38, the igniting agent 39 is first ignited by the flame generated by ignition of the igniting agent 35, and the flame generates gas. Propagated to the agent 38, the gas generating agent 38 burns quickly. The generated combustion gas is ejected from the gas ejection hole 44 through the filter 42 to inflate the airbag 45.

The effects of the first embodiment described above are summarized below.
The igniting agents 26 and 39 for the gas generator of the present embodiment are configured such that the burning rates of the igniting agents 26 and 39 are faster than the burning rates of the non-azide gas generating agents 25 and 38. Therefore, the igniting agents 26 and 39 are ignited faster than the gas generating agents 25 and 38, the propagation of combustion during combustion is quick, and the combustion of the gas generating agents 25 and 38 can proceed rapidly. Therefore, the ignitability and combustibility of the non-azide gas generating agents 25 and 38 can be improved while maintaining a high gasification rate.

  The combustion speed is defined by the arrival time from the start of energization to the ignition unit to the maximum pressure due to the gas generated in the combustion chambers 24 and 32. The arrival time of the igniting agents 26 and 39 is configured to be shorter than the arrival time of the non-azide gas generating agent. Accordingly, the ignitability and combustibility of the non-azide gas generating agents 25 and 38 can be further improved.

  Further, when the gas generator for the occupant protection device is the pretensioner gas generator 12 configured to draw the seat belt 15 by the gas generated in the combustion chamber 24, the ignition agents 26 and 39 are The effect can be demonstrated.

  Further, when the occupant protection device gas generator is the airbag gas generator 30 configured to inflate the airbag 45 with the gas generated in the combustion chamber 32, the ignition agents 26 and 39 are The effect of can be demonstrated.

Hereinafter, the embodiment will be described more specifically with reference to Examples, Reference Examples, Production Examples, and Comparative Examples.
Example 1
To a mixture of 788% by mass of potassium perchlorate having an average particle size of 30 μm and 212% by mass of cellulose acetate butyrate, a mixed solution in which 20% by mass of acetone and 10% by mass of ethyl alcohol are mixed is added. Mix evenly on the machine. The Werner-mixer is a device that stirs and mixes with a stirring blade supported by a rotating shaft extending in the lateral direction.

This mixture was then loaded into an extruder. A die having a hole diameter of 095 mm and a pin having a diameter of 025 mm are attached in advance to the extrusion apparatus. Then, by applying pressure to the mixture, the mixture is extruded while passing through the holes of the die and formed into a single-hole cylindrical shape having one through hole. The molded product was cut into a length of 20 mm and dried to obtain a granular igniter. Table 1 shows the dimensions of the obtained igniting agent. Moreover, in order to confirm whether the arrival time from the start of energization of this igniter to the maximum pressure was 5 to 20 milliseconds, the above-described sealed bomb combustion test was performed. The obtained arrival times are shown in Table 1.
( Reference Example 2, Example 3, Reference Example 4, Example 5, Reference Example 6, Reference Example 7 )
With the compositions shown in Table 1, each igniter was produced by the same method as in Example 1, and each characteristic was evaluated by the same method as in Example 1. The results are shown in Table 1.
(Example 8)
Mixing 30% by mass of acetone and 5% by mass of water to a mixture of 852% by mass of potassium perchlorate having an average particle size of 30 μm, 30% by mass of cellulose acetate butyrate, 20% by mass of acetyltributyl citrate and 98% by mass of activated carbon The mixed solution was added and mixed uniformly with a Werner-mixer.

This mixture was then loaded into a granulator. A punching metal having a hole diameter of 035 mm is attached to the granulator in advance. And by applying a pressure to a mixture, the mixture was extruded passing the hole of the punching metal, and the granular ignition agent was obtained. Table 1 shows the dimensions of the obtained igniting agent. Moreover, in order to confirm whether the arrival time from the energization start of this igniting agent to the maximum pressure is 5 to 20 milliseconds, a closed bomb combustion test was conducted. The obtained arrival times are shown in Table 1.
( Reference Example 9)
With the composition shown in Table 1, an ignition agent was produced by the same method as in Example 8, and the characteristics were evaluated in the same manner as in Example 8. The results are shown in Table 1.

（プリテンショナー用ガス発生剤の製造例１）
平均粒径８０μｍの硝酸アンモニウム９００質量％、酢酸酪酸セルロ−ス６０質量％、クエン酸アセチルトリブチル３０質量％及び活性炭１０質量％の混合物に対し、アセトン２０質量％及びエチルアルコ−ル１０質量％を混合した混合溶液を加え、ウェルナー混和機で均一に混合した。

(Production Example 1 of Pretensioner Gas Generating Agent)
To a mixture of 900% by mass of ammonium nitrate having an average particle size of 80 μm, 60% by mass of cellulose acetate butyrate, 30% by mass of acetyltributyl citrate and 10% by mass of activated carbon, 20% by mass of acetone and 10% by mass of ethyl alcohol were mixed. The mixed solution was added and mixed uniformly with a Werner mixer.

This mixture was then loaded into an extruder. A die having a hole diameter of 1.75 mm and a pin having a diameter of 0.25 mm are attached to the extrusion apparatus in advance. Then, by applying pressure to the mixture, the mixture is extruded while passing through a die and formed into a single-hole cylindrical shape having one through hole. The molded product was cut into a length of 2.0 mm and dried to obtain a granular pretensioner gas generating agent. Table 2 shows the dimensions of the obtained ignition agent.
(Production Example 2 of Gas Generator for Pretensioner)
With the composition and shape shown in Table 2, a gas generating agent was manufactured by the same method as in Production Example 1 of the gas generator for pretensioner. The results are shown in Table 2.

（実施例１０）
プリテンショナー用ガス発生剤の製造例１のガス発生剤が９１質量％、実施例１の着火剤が９質量％の割合となるように混合し、この混合物を密閉ボンブ燃焼装置で燃焼させた。この組成物のガス化率を理論計算（組成物の燃焼生成物のうち気体成分の質量割合を％で表記した。）より求め、また通電開始から最大圧力までの到達時間がプリテンショナー用ガス発生剤に要求される１５〜３０ミリ秒であるか否か確認を行った。得られた到達時間を表３に示す。

(Example 10)
Preparation of gas generating agent for pretensioner The gas generating agent of Production Example 1 was mixed at a ratio of 91% by mass and the igniting agent of Example 1 at 9% by mass, and this mixture was burned in a closed bomb combustion apparatus. The gasification rate of this composition is determined by theoretical calculation (the mass ratio of the gas component in the combustion product of the composition is expressed in%), and the time from the start of energization to the maximum pressure is generated for pretensioner gas generation It was confirmed whether it was 15-30 milliseconds required for the agent. Table 3 shows the obtained arrival times.

（参考例１１、実施例１２、参考例１３、実施例１４、実施例１５、参考例１６、実施例１７、参考例１８、実施例１９、参考例２０及び実施例２１）
表３に示した質量比となるように組成物を混合し、各々の特性を実施例１０と同じ方法で評価した。得られた結果を表３に示す。また、密閉ボンブ燃焼試験により得られた実施例１７の燃焼カーブを代表例として図６に示す。
（比較例１及び２）
着火剤を使用せず、プリテンショナー用ガス発生剤のみでの特性を実施例１０と同じ方法で評価した。それらの結果を表３に示す。また、密閉ボンブ燃焼試験により得られた比較例２の燃焼カーブを代表例として図５に示す。

( Reference Example 11 , Example 12, Reference Example 13, Example 14, Example 15, Reference Example 16, Example 17, Reference Example 18, Example 19, Reference Example 20 and Example 21)
The compositions were mixed so that the mass ratios shown in Table 3 were obtained, and each characteristic was evaluated by the same method as in Example 10. The obtained results are shown in Table 3. Moreover, the combustion curve of Example 17 obtained by the closed bomb combustion test is shown in FIG. 6 as a representative example.
(Comparative Examples 1 and 2)
The characteristics of the pretensioner gas generating agent alone were evaluated by the same method as in Example 10 without using an ignition agent. The results are shown in Table 3. Moreover, the combustion curve of the comparative example 2 obtained by the closed bomb combustion test is shown in FIG. 5 as a representative example.

From the test results of Tables 1 to 3 and FIGS. 5 and 6, the following was found.
That is, the ignition agents shown in Examples or Reference Examples 1 to 9 were able to adjust the arrival time from the start of energization to the maximum pressure to 8 to 14 milliseconds. On the other hand, in the pretensioner gas generating agents of Comparative Examples 1 and 2 in which no igniting agent is blended, the arrival time is 30 milliseconds or more due to low ignitability and low flammability. It became clear that it could not be used as a gas generating agent. On the other hand, in Examples or Reference Examples 10 to 21 in which an igniting agent was blended, since the ignitability and combustibility were improved, the arrival time was in the range of 15 to 30 milliseconds, which can be used as a gas generator for pretensioners. It became clear that.

  Further, in the combustion pattern of only the pretensioner gas generating agent shown in Comparative Example 2 (FIG. 5), the combustion speed at the initial stage of combustion (from the start of energization to about 23 milliseconds) is very slow, and the middle stage of combustion (about 23 millimeters). It became a so-called S-shape in which the combustion speed increases rapidly from (after the second), and it was found that there was a problem in combustibility. On the other hand, the combustion pattern of the pretensioner gas generating agent blended with the igniting agent shown in Example 17 (FIG. 6) has a high combustion speed from the initial stage of combustion, and is a so-called linear type, and the combustibility is greatly increased. It was found that it was improved.

Moreover, as a result of testing about the heat resistance of Example 17 and the carbon monoxide concentration after combustion, it was confirmed that there was no problem. It was found that Reference Example 20 has a tendency to slow the arrival time although it can be used as a gas generating agent for a pretensioner because the blending ratio of the ignition agent is small. Furthermore, in Example 21, since the blending ratio of the igniting agent was large, it was found that although it can be used as a pretensioner gas generating agent, the gasification rate tends to decrease.

It should be noted that the above-described embodiment can be modified as follows .

  The content of the igniting agents 26 and 39 with respect to the non-azide-based gas generating agents 25 and 38 can be made higher in the case of the pretensioner gas generator 12 than in the case of the air bag gas generator 30. In this case, the entire non-azide gas generating agent accommodated in the combustion chamber 24 of the pretensioner gas generator 12 can be sufficiently combusted.

  -Non-azide gas generating agents can contain combustion catalysts, environmental stabilizers, and the like. As the combustion catalyst, copper oxide, iron oxide, manganese oxide or the like is used. As the environmental stabilizer, oxyethylene dodecylamine, polyoxyethylene dodecylamine, polyoxyethylene octadecylamine and the like are used.

-It can replace with the groove | channel 27 of the said gas generator 12 for pretensioners, and can also form it so that a through-hole may be opened and there may be closed with a rupture disk .

Furthermore, the technical idea grasped from the embodiment will be described below.
(1) The gas generator according to any one of claims 1 to 3, wherein the igniting agent is configured to be contained in the combustion chamber in a state of being mixed with a non-azide gas generating agent. Ignition agent. When comprised in this way, the ignitability and combustibility of a non-azide type gas generating agent can be improved more.

  (2) The oxygen balance of the non-azide-based gas generating agent is substantially ± 0, and the oxygen balance of the igniting agent is positive. The gas generator according to any one of claims 1 to 3, Ignition agent. When comprised in this way, the ignition property and combustibility of an ignition agent can be improved, suppressing generation | occurrence | production of noxious gases, such as nitrogen dioxide.

  (3) The non-azide gas generating agent contains an oxidizing agent and a fuel, the oxidizing agent is an ammonium salt, the igniting agent contains an oxidizing agent and a fuel, and the oxidizing agent is a potassium salt. Item 4. The igniter for a gas generator according to any one of items 3 to 4. When comprised in this way, while being able to raise the gasification rate of a non-azide type gas generating agent, the ignitability and combustibility of an ignition agent can be improved.

  (4) The non-azide gas generating agent contains perchlorate as an oxidant, and also contains fuel and an alkali metal salt of nitric acid, and the ignition agent contains perchlorate as an oxidant. 4. The igniter for a gas generator according to claim 1, wherein the igniter contains a fuel, and hydrogen chloride generated during combustion reacts with an alkali metal salt of nitric acid. 5. . When comprised in this way, it can prevent that harmful hydrogen chloride generate | occur | produces at the time of combustion of a gas generating agent.

  (5) The non-azide gas generating agent contains an oxidant and a fuel, the igniting agent contains an oxidant and a fuel, and the oxidant in the igniting agent is nitrate, nitrite or oxohalogenate, The ignition agent for a gas generator according to any one of claims 1 to 3, wherein is a polymer binder, powdered microcrystalline carbon, or a nitrogen-containing compound.

(6) The igniter for a gas generator according to the technical concept (5), further comprising a plasticizer, a aging stabilizer, or a slag forming agent.
(7) The ignition for a gas generator according to the technical idea (5) or (6), wherein the oxidant content in the igniter is 68 to 98% by mass and the fuel content is 2 to 32% by mass. Agent.

  (8) The gas generator according to any one of claims 1 to 3, wherein the content of the non-azide gas generating agent is 60 to 98 mass% and the content of the igniting agent is 2 to 40 mass%. Ignition agent.

The schematic sectional drawing which shows the gas generator for pretensioners in embodiment. (A) is a schematic front view which shows a pretensioner with the principal part fractured | ruptured, (b) is a schematic side view which fractures | ruptures a principal part and shows a pretensioner. The schematic sectional drawing which shows a sealing bomb combustion test apparatus. Sectional drawing which shows the gas generator for airbags. The graph which shows the relationship between the time in Comparative Example 2, and a combustion pressure. 18 is a graph showing the relationship between time and combustion pressure in Example 17.

Explanation of symbols

DESCRIPTION OF SYMBOLS 12 ... Gas generator for pretensioners, 15 ... Seat belt, 22 ... Electric igniter as an ignition part, 24, 32 ... Combustion chamber, 25, 38 ... Gas generating agent, 26, 39 ... Ignition agent, 30 ... Air bag Gas generator, 31 ... ignition part, 34 ... electric igniter constituting ignition part, 35 ... ignition agent constituting ignition part, 45 ... air bag.

Claims (3)

It is used for a gas generator for a vehicle occupant protection device including a combustion chamber in which a gas generating agent that generates gas by combustion is accommodated, and an ignition unit that develops an ignition function by energization to burn the gas generating agent. An igniting agent contained in the combustion chamber or ignition part, wherein the gas generating agent is a non-azide gas generating agent containing ammonium nitrate or ammonium perchlorate as an oxidant , and the igniter is an excess of oxidant. It contains potassium chlorate and is configured such that the burning rate of the igniting agent is faster than the burning rate of the non-azide gas generating agent, and the gas generator for the occupant protection device uses a gas generated in the combustion chamber to seat belt An ignition agent for a gas generator, characterized by being a gas generator for a pretensioner configured to draw in the gas. The combustion speed is defined by the arrival time from the start of energization to the ignition part to the maximum pressure due to the gas generated in the combustion chamber, and is configured such that the arrival time of the ignition agent is shorter than the arrival time of the non-azide gas generating agent. The igniter for a gas generator according to claim 1. The arrival time of the igniting agent is the maximum due to the gas generated in the sealed container from the start of energization to the ignition part in the combustion test when the igniting agent or gas generating agent is loaded in the sealed container so as to have a loading density of 0059 g / ml. The igniter for a gas generator according to claim 2, wherein the igniter for the gas generator according to claim 2, wherein the igniter is determined based on an arrival time to the pressure, and is 5 to 20 milliseconds for the igniter and 25 to 100 milliseconds for the non-azide gas generant. .

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