U.S. patent application number 12/326454 was filed with the patent office on 2009-06-11 for gelatinous enhancer for inflator.
Invention is credited to Shoji KOBAYASHI, Nobuyuki OHJI.
Application Number | 20090145528 12/326454 |
Document ID | / |
Family ID | 40491008 |
Filed Date | 2009-06-11 |
United States Patent
Application |
20090145528 |
Kind Code |
A1 |
OHJI; Nobuyuki ; et
al. |
June 11, 2009 |
GELATINOUS ENHANCER FOR INFLATOR
Abstract
The present invention relates to a gelatinous enhancer for an
inflator, including silicone oil and ammonium nitrate.
Inventors: |
OHJI; Nobuyuki; (Hyogo,
JP) ; KOBAYASHI; Shoji; (Hyogo, JP) |
Correspondence
Address: |
BIRCH STEWART KOLASCH & BIRCH
PO BOX 747
FALLS CHURCH
VA
22040-0747
US
|
Family ID: |
40491008 |
Appl. No.: |
12/326454 |
Filed: |
December 2, 2008 |
Current U.S.
Class: |
149/60 |
Current CPC
Class: |
C06B 45/00 20130101;
C06D 5/06 20130101; C06B 31/285 20130101; C06B 45/10 20130101 |
Class at
Publication: |
149/60 |
International
Class: |
C06B 31/30 20060101
C06B031/30 |
Foreign Application Data
Date |
Code |
Application Number |
Dec 11, 2007 |
JP |
2007-319125 |
Claims
1. A gelatinous enhancer for an inflator, comprising silicone oil
and ammonium nitrate.
2. The gelatinous enhancer according to claim 1, wherein the
silicone oil content ranges from 5 to 35 mass % and the ammonium
nitrate content ranges from 65 to 95 mass %.
Description
[0001] This nonprovisional application claims priority under 35
U.S.C. .sctn.119(a) on Patent Application No. 2007-319125 filed in
Japan on 11 Dec. 2007, which is incorporated by reference.
BACKGROUND OF INVENTION
[0002] 1. Field of Invention
[0003] The present invention relates to a gelatinous enhancer for
an inflator, which is used in an inflator for an air bag apparatus
or other applications.
[0004] 2. Description of Arts
[0005] B/KNO.sub.3 is widely employed as a enhancer for an
inflator. B/KNO.sub.3 has a high combustion temperature and
favorable ignitability in relation to a gas generant. However,
B/KNO.sub.3 burns vigorously, and therefore burns out
instantaneously. Hence, B/KNO.sub.3 is insufficient as a enhancer
for a gas generant having low ignitability. Furthermore,
B/KNO.sub.3 is expensive and exhibits a low gas efficiency.
[0006] Further, when E/KNO.sub.3 is used, a problem arises in that
an abnormal noise occurs during an operation. This problem can be
solved by employing a elastic enhancer, but an elastic enhancer is
easily affected by the environmental temperature and is therefore
unsatisfactory in terms of operational reliability over a wide
temperature range (-40.degree. C. to 105.degree. C.). US-A No.
2005/0235863, JP-A No. 2000-8637 and JP-A No. 2002-12493 are in the
state of arts.
SUMMARY OF INVENTION
[0007] An invention relates to a gelatinous enhancer for an
inflator, including silicone oil and ammonium nitrate.
DETAILED DESCRIPTION OF INVENTION
[0008] The present invention provides a gelatinous enhancer for an
inflator, which can solve problems relating to costs, ignitability
in relation to a gas generant, and so on.
[0009] The invention preferably relates to a gelatinous enhancer
for an inflator, wherein the silicone oil content ranges from 5 to
35 mass % and the ammonium nitrate content ranges from 65 to 95
mass %.
[0010] The gelatinous enhancer for an inflator according to the
present invention generates more combustion heat than B/KNO.sub.3,
which is widely used as a enhancer, and therefore exhibits
favorable ignitability in relation to a gas generant having low
ignitability. Further, the gas efficiency of the gelatinous
enhancer for an inflator according to the present invention is
high, and therefore gas generated thereby can be used also to
inflate an air bag. Thus, gas generated from the gas generant can
be complemented by the gas generated by the gelatinous
enhancer.
PREFERRED EMBODIMENT OF INVENTION
[0011] Known silicone oil is used in the present invention (see
[0016] to [0019] of US-A No. 2005/0235863, for example), and either
straight silicone oil or denatured silicone oil may be used.
However, straight silicone oil (polydimethylsiloxane, for example)
is preferable.
[0012] To provide the enhancer in a gelatinous form, the viscosity
of the silicone oil is preferably within a range of 100 to 20,000
cm.sup.2/s, more preferably within a range of 500 to 15,000
cm.sup.2/s, and even more preferably within a range of 1000 to
15,000 cm.sup.2/s. The method of measuring the viscosity
corresponds to the method described in JIS K2283, and a value
measured at 25.degree. C. is taken.
[0013] The silicone oil content is preferably between 3 and 30 mass
%, more preferably between 5 and 25 mass %, and even more
preferably between 5 and 20 mass %.
[0014] Ammonium nitrate used in the present invention may be a
normal ammonium nitrate or an ammonium nitrate subjected to phase
stabilization by a known method (for example, JP-A No. 2002-338241,
JP-A No. 2006-520312, JP-A No. 10-259085) using potassium nitrate,
an inorganic potassium salt such as potassium perchlorate, an
organic potassium salt such as potassium oxalate, or the like.
[0015] The ammonium nitrate content is preferably between 70 and 97
mass %, more preferably between 75 and 95 mass %, and even more
preferably between 80 and 95 mass %.
[0016] The gelatinous enhancer for an inflator according to the
present invention may be a three component-based enhancer including
a nitrogen-containing compound in addition to the silicone oil and
ammonium nitrate described above. When a nitrogen-containing
compound is included, the gas efficiency (mol/100 g; expressing the
number of moles of gas generated per 100 g of gas generant)
increases and an initial pressure upon ignition increases,
preferably leading to an improvement in ignitability in relation to
the gas generant.
[0017] When a nitrogen-containing compound is included, the
nitrogen-containing compound content is preferably 30 mass % or
less of the total amount of the ammonium nitrate and the
nitrogen-containing compound.
[0018] The nitrogen-containing compound may be selected from a
tetrazole derivative, guanidine, guanidine carbonate,
nitroguanidine, dicyandiamide, nitroaminoguanidine, and
nitroaminoguanidine nitrate.
[0019] Examples of tetrazole derivatives include tetrazole,
5-aminotetrazole, 5,5'-bi-1H-tetrazole, 5-nitroaminotetrazole,
5-aminotetrazole zinc salt, 5-aminotetrazole copper salt,
bitetrazole, bitetrazole potassium salt, bitetrazole sodium salt,
bitetrazole magnesium salt, bitetrazole calcium salt, bitetrazole
diammonium salt, bitetrazole copper salt, and bitetrazole melamine
salt.
[0020] The gelatinous enhancer for an inflator according to the
present invention can be obtained by blending a predetermined
amount of silicone oil, a predetermined amount of ammonium nitrate,
and in certain cases, a predetermined amount of a
nitrogen-containing compound.
[0021] The gelatinous enhancer for an inflator according to the
present invention can be applied to various types of inflators
having a known gas generant, for example an inflator for an air bag
used in a driver side, an inflator for an air bag for a front
passenger side, an inflator for a side air bag, an inflator for an
inflatable curtain, an inflator for a knee bolster, an inflator for
an inflatable seatbelt, an inflator for a tubular system, and an
inflator for a pretensioner of various types of vehicles.
EXAMPLES
Examples and Comparative Example
[0022] By blending the components shown in Table 1, a gelatinous
enhancer for an inflator according to Examples and a enhancer
according to Comparative Example were obtained. The following tests
were performed on these enhancers. The results are shown in Table
1.
(1) Combustion Temperature (K)
[0023] A simulation value based on a thermochemical equilibrium
calculation program.
(2) Combustion Heat (cal/g)
[0024] A simulation value based on a thermochemical equilibrium
calculation program.
(3) Gas Efficiency (mol/100 g)
[0025] A simulation value based on a thermochemical equilibrium
calculation program.
(4) Friction Sensitivity (N), Drop Hammer Sensitivity (cm)
[0026] The friction sensitivity (N) and the drop hammer sensitivity
(cm) were measured on the basis of an explosive performance test
method described in JIS K4810-1979.
TABLE-US-00001 TABLE 1 Drop Combustion Friction hammer temperature
Combustion Gas efficiency sensitivity sensitivity Gas generant
composition (mass %) (K) heat (cal/g) (mol/100 g) (N) (cm) Example
1 Silicone oil(1)/Ammonium nitrate = 10.4/89.6 2393 1191 4.06
>353 50-60 Example 2 Silicone oil(2)/Ammonium nitrate =
10.4/89.6 2393 1191 4.06 >353 50-60 Example 3 Silicone
oil(3)/Ammonium nitrate = 10.4/89.6 2393 1191 4.06 >353 50-60
Comparative B/KNO.sub.3 = 25/75 3089 827 1.34 >353 30-40 Example
1
[0027] Ammonium nitrate: product name K-320 (manufactured by
Sumitomo Chemical Co., Ltd.) [0028] Silicone oil (1): product name
TSF451-30M (manufactured by Momentive Performance Materials Japan
LLC.), viscosity 3000 cm.sup.2/s [0029] Silicone oil (2): product
name KF-96 (manufactured by Shin-Etsu Chemicals Co., Ltd.),
viscosity 5,000 cm.sup.2/s [0030] Silicone oil (3): product name
KF-96H (manufactured by Shin-Etsu Chemicals Co., Ltd.), viscosity
10,000 cm.sup.2/s
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