U.S. patent application number 11/368681 was filed with the patent office on 2006-09-14 for grease composition for harnesses.
This patent application is currently assigned to Kyodo Yushi Co., Ltd.. Invention is credited to Shozo Ikejima, Kyosuke Ikuma, Hiroshi Kimura, Masahiko Morikawa, Keiji Sasaki, Masahiko Sugaya, Ko Yaegashi.
Application Number | 20060205613 11/368681 |
Document ID | / |
Family ID | 36934070 |
Filed Date | 2006-09-14 |
United States Patent
Application |
20060205613 |
Kind Code |
A1 |
Ikuma; Kyosuke ; et
al. |
September 14, 2006 |
Grease composition for harnesses
Abstract
The present invention relates to a grease composition for use in
harnesses, which comprises a thickening agent, a base oil and
additives, wherein the base oil comprises a polyoxyalkylene glycol
ether and the additives comprise a quinoline compound and a
benzotriazole compound. The grease composition is quite excellent
in the corrosion resistance, the oxidation stability and the
compatibility with materials such as olefinic elastomer.
Inventors: |
Ikuma; Kyosuke;
(Fujisawa-shi, JP) ; Yaegashi; Ko; (Fujisawa-shi,
JP) ; Kimura; Hiroshi; (Fujisawa-shi, JP) ;
Sasaki; Keiji; (Kariya-shi, JP) ; Ikejima; Shozo;
(Kariya-shi, JP) ; Sugaya; Masahiko; (Kariya-shi,
JP) ; Morikawa; Masahiko; (Kariya-shi, JP) |
Correspondence
Address: |
NIXON & VANDERHYE, PC
901 NORTH GLEBE ROAD, 11TH FLOOR
ARLINGTON
VA
22203
US
|
Assignee: |
Kyodo Yushi Co., Ltd.
Tokyo
JP
Denso Corporation
Kariya-shi
JP
|
Family ID: |
36934070 |
Appl. No.: |
11/368681 |
Filed: |
March 7, 2006 |
Current U.S.
Class: |
508/163 |
Current CPC
Class: |
C10N 2030/10 20130101;
C10M 2207/2825 20130101; C10M 2207/129 20130101; C10N 2030/36
20200501; C10N 2030/12 20130101; C10N 2020/02 20130101; C10M
2215/221 20130101; C10M 2207/127 20130101; C10M 2201/145 20130101;
C10N 2050/10 20130101; C10M 2207/1285 20130101; C10M 2215/223
20130101; C10M 169/00 20130101; C10M 2207/289 20130101; C10M
2209/1055 20130101; C10M 2207/1285 20130101; C10N 2010/02 20130101;
C10M 2209/1055 20130101; C10M 2209/1085 20130101; C10M 2207/1285
20130101; C10N 2010/02 20130101 |
Class at
Publication: |
508/163 |
International
Class: |
C10M 169/06 20060101
C10M169/06 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 14, 2005 |
JP |
2005-071455 |
Claims
1. A grease composition for use in harnesses, which comprises a
thickening agent, a base oil and additives, wherein the base oil
comprises a polyoxyalkylene glycol ether and the additives comprise
a quinoline compound and a benzotriazole compound.
2. The grease composition for use in harnesses as set forth in
claim 1, wherein the thickening agent is at least one member
selected from the group consisting of lithium soaps and bentonite
modified with organic compounds.
3. The grease composition for use in harnesses as set forth in
claim 1, wherein the polyoxyalkylene glycol ether has a kinematic
viscosity as determined at a temperature of 40.degree. C. ranging
from 30 to 400 mm.sup.2/s.
4. The grease composition for use in harnesses as set forth in
claim 1, wherein the content of the quinoline compound ranges from
0.1 to 10% by mass on the basis of the total mass of the grease
composition and the content of the benzotriazole compound ranges
from 0.1 to 10% by mass on the basis of the total mass of the
grease composition.
5. The grease composition for use in harnesses as set forth in
claim 2, wherein the polyoxyalkylene glycol ether has a kinematic
viscosity as determined at a temperature of 40.degree. C. ranging
from 30 to 400 mm.sup.2/s.
6. The grease composition for use in harnesses as set forth in
claim 2, wherein the content of the quinoline compound ranges from
0.1 to 10% by mass on the basis of the total mass of the grease
composition and the content of the benzotriazole compound ranges
from 0.1 to 10% by mass on the basis of the total mass of the
grease composition.
7. The grease composition for use in harnesses as set forth in
claim 3, wherein the polyoxyalkylene glycol ether has a kinematic
viscosity as determined at a temperature of 40.degree. C. ranging
from 30 to 400 mm.sup.2/s.
8. The grease composition for use in harnesses as set forth in
claim 3, wherein the content of the quinoline compound ranges from
0.1 to 10% by mass on the basis of the total mass of the grease
composition and the content of the benzotriazole compound ranges
from 0.1 to 10% by mass on the basis of the total mass of the
grease composition.
Description
BACKGROUND OF THE INVENTION
[0001] The present invention relates to a grease composition for
use in a harness.
[0002] In various automotive engine accessories, in particular,
harness members arranged in the proximity to an air conditioner,
the condensed water originated from, for instance, the moisture
present in the atmosphere may penetrate into, for instance, a
connector to thus corrode metallic parts constituting the same
(materials for contact parts) and therefore, these metallic parts
should certainly be protected from such corrosion. In addition, a
lubricant (a grease composition obtained by adding a thickening
agent to a base oil and then forming the resulting blend into a
semi-solid product) should satisfy, for instance, the following
requirements: it should have excellent corrosion resistance and
oxidation stability in order that these parts can be used over a
long period of time or in order to extend the service life of the
parts. Furthermore, olefinic elastomers have recently been
substituted for the polyvinyl chloride as a coating material for
metallic parts for the purpose of reducing the quantity of
materials which may not be environment-friendly and accordingly, it
has been desired to design such a grease composition while taking
into consideration the compatibility thereof with the coating
materials for such parts.
[0003] Conventionally, as a grease composition for filling up the
distributing wire connector of a wire harness used for automobiles,
there has been reported a grease composition having excellent heat
resistance (Patent Document 1: JP-B-6-99702). However, this grease
composition employs a purified mineral oil as a base oil and
therefore, this grease composition is considered to have low
compatibility with, for instance, olefinic elastomers and this
composition is not designed to take into sufficient consideration
the corrosion resistance and the oxidation stability.
[0004] In addition, there has also been reported a grease
composition for use in a speed-reducing device (gear), which is
excellent in the anticorrosive properties and which does not
adversely affect materials such as rubber materials too much
(Patent Document 2: JP-A-4-266995; Patent Document 3:
JP-A-63-309591; and Patent Document 4: JP-A-64-29496). These grease
compositions can satisfy the requirement for the compatibility with
the coating materials for such parts, for instance, olefinic
elastomers, but they are not always sufficient in the corrosion
resistance and the oxidation stability.
DISCLOSURE OF THE INVENTION
[0005] Accordingly, it is an object of the present invention to
provide a grease composition for harnesses and more particularly to
provide a grease composition for harnesses, which is excellent in
the compatibility with the coating materials for parts of harnesses
such as olefinic elastomers, the corrosion resistance and the
resistance to oxidation.
[0006] The inventors of this invention have thus conducted various
studies to eliminate the foregoing drawbacks associated with the
foregoing conventional techniques concerning grease compositions
for, in particular, harnesses, have found that the foregoing
drawbacks can efficiently be eliminated by the use of a base oil
containing a specific component and specific compounds as additives
for the grease composition and have thus completed the present
invention.
[0007] According to the present invention, there is thus provided a
grease composition for use in harnesses, which comprises a
thickening agent, a base oil and additives, wherein the base oil
comprises a polyoxyalkylene glycol ether and the additives comprise
a quinoline compound and a benzotriazole compound.
[0008] In a preferred embodiment of the grease composition for use
in harnesses according to the present invention, the thickening
agent is at least one member selected from the group consisting of
lithium soaps and bentonite materials modified with organic
compounds (organically modified bentonite materials).
[0009] In a further preferred embodiment of the grease composition
for use in harnesses according to the present invention, the
polyoxyalkylene glycol ether has a kinematic viscosity as
determined at a temperature of 40.degree. C. ranging from 30 to 400
mm.sup.2/s.
[0010] In a still further preferred embodiment of the grease
composition for use in harnesses according to the present
invention, the content of the quinoline compound ranges from 0.1 to
10% by mass on the basis of the total mass of the grease
composition, and the content of the benzotriazole compound ranges
from 0.1 to 10% by mass on the basis of the total mass of the
grease composition.
[0011] The grease composition of the present invention makes use of
a polyoxyalkylene glycol ether-containing base oil and comprises,
as additives, a quinoline compound and a benzotriazole compound and
therefore, the grease composition is excellent in the compatibility
with the coating materials for parts of harnesses such as olefinic
elastomers, the corrosion resistance and the resistance to
oxidation.
BEST MODE FOR CARRYING OUT THE INVENTION
[0012] The grease composition of the present invention is
characterized in that it uses, as a base oil, one containing a
polyoxyalkylene glycol ether, which does not adversely affect the
olefinic materials too much. Preferably used in the present
invention are polyoxyalkylene glycol ethers represented by the
following general formula I:
R.sup.1O--(CH.sub.2CHR.sup.2O).sub.n--R.sup.3 Formula I
[0013] In Formula I, R.sup.1 and R.sup.3 each independently
represents a hydrogen atom or an alkyl group having 1 to 20,
preferably 1 to 6 carbon atoms (such as a methyl group, an ethyl
group, a propyl group, an isopropyl group, a butyl group, an
isobutyl group, a pentyl group or a hexyl group); R.sup.2
represents an alkyl group having 1 to 10, preferably 1 to 4 carbon
atoms (such as a methyl group, an ethyl group, a propyl group or a
butyl group); and n represents a numeral ranging from 5 to 30 and
preferably 8 to 20, provided that R.sup.1 and R.sup.3 do not
simultaneously represent hydrogen atoms.
[0014] Specific examples of the polyoxyalkylene moieties of the
polyoxyalkylene glycol ethers represented by the general formula I
include polyoxyethylene, polyoxypropylene,
poly(oxypropylene-oxyethylene), poly(oxybutylene-oxyethylene),
poly(oxybutylene-oxypropylene), poly(oxypentylene-oxyethylene) and
poly(oxypentylene-oxypropylene).
[0015] The polyoxyalkylene glycol ethers represented by the general
formula I usable herein may be a mono-ether or a di-ether and
specific examples thereof include polyoxypropylene monopropyl
ether, polyoxypropylene monobutyl ether, polyoxybutylene monobutyl
ether, polyoxyethylene oxypropylene monopropyl ether,
polyoxyethylene oxypropylene monobutyl ether, polyoxyethylene
oxypropylene monopentyl ether, and polyoxypropylene dimethyl ether.
Preferred are polyoxypropylene monobutyl ether, and
polyoxypropylene dimethyl ether, most preferred is polyoxypropylene
dimethyl ether.
[0016] Preferably, the base oil used in the present invention
comprises a polyoxyalkylene glycol ether in an amount of preferably
not less than 50% by mass, more preferably not less than 80% by
mass and most preferably 100% by mass on the basis of the total
mass of the base oil. The base oil used in the present invention
may further comprise other base oil materials currently used in the
grease composition such as mineral oils, synthetic hydrocarbon
oils, and alkyl diphenyl ether oils in addition to the
polyoxyalkylene glycol ether, but the amount thereof is preferably
less than 10% by mass on the basis of the total mass of the base
oil.
[0017] The kinematic viscosity of the polyoxyalkylene glycol ether
as determined at 40.degree. C. preferably ranges from 30 to 400
mm.sup.2/s and more preferably 80 to 120 mm.sup.2/s.
[0018] As the thickening agent used in the grease composition for
harnesses according to the present invention, there may be listed,
for instance, those conventionally known in this art such as metal
salts of fatty acids, bentonite modified with organic compounds and
PTFE, with metal salts of fatty acids and bentonite modified with
organic compounds being particularly preferably used herein.
[0019] As the constituent fatty acids of the foregoing metal salts
of fatty acids, preferably used herein are those having 10 to 30
and more preferably 16 to 20 carbon atoms and examples thereof
preferably used herein are lauric acid, myristic acid, palmitic
acid, stearic acid, 12-hydroxy stearic acid and oleic acid.
Moreover, as the metal salts of these fatty acids, there may be
mentioned, for instance, alkali metal salts such as sodium and
lithium salts, alkaline earth metal salts such as barium and
calcium salts and trivalent metal salts such as aluminum salts.
Usable herein further include, for instance, salts of mixtures each
comprising at least two fatty acids including dibasic acids with
metals such as aluminum, calcium and lithium, or complex metallic
soaps. Among these metal salts of fatty acids, most preferably used
herein is lithium 12-hydroxy stearate because of its excellent
water resistance, heat resistance and mechanical stability.
[0020] The amount of the thickening agent to be incorporated into
the grease composition of the present invention preferably ranges
from 2 to 35 parts by mass and more preferably 5 to 15 parts by
mass per 100 parts by mass of the base oil. This is because, if the
amount thereof is less than 2 parts by mass, there would be
observed such a tendency that the resulting grease composition is
in a highly fluidized state and it is thus too soft, while if the
amount thereof exceeds 35 parts by mass, the resulting composition
is liable to be too hard to use as a grease composition for
harnesses.
[0021] Examples of quinoline compounds used in the grease
composition for harnesses according to the present invention are
compounds represented by the following general formula II, such as
trimethyl dihydro-quinoline oligomer. ##STR1##
[0022] In Formula II, R.sup.4, R.sup.5 and R.sup.6 may be the same
or different and each preferably represents an alkyl group
preferably having 1 to 10 and more preferably 1 to 3 carbon atoms
and n is a numeral preferably ranging from 1 to 10 and more
preferably 1 to 5.
[0023] Particularly preferred such quinoline compounds are, for
instance, trimethyl dihydro-quinoline oligomers (n=2 to 3).
[0024] The amount of these quinoline compounds to be incorporated
into the grease composition of the present invention preferably
ranges from 0.1 to 10% by mass, more preferably 0.5 to 5% by mass
and most preferably 1.0 to 3% by mass on the basis of the total
mass of the grease composition.
[0025] The grease composition of the present invention may further
comprise other anti-oxidants, for instance, a phenolic compound
such as 2,6-di-t-butyl cresol and/or an amine compound such as
phenyl-.alpha.-naphthyl-amine, in combination with the foregoing
components. In this respect, the content thereof used herein is
desirably not more than 5.0% by mass on the basis of the total mass
of the grease composition.
[0026] The grease composition for harnesses according to the
present invention may comprise a benzotriazole compound as the
corrosion inhibitor. Examples of such benzotriazole compounds
preferably used herein are those represented by the following
general formula III: ##STR2##
[0027] In Formula III, R.sup.7 represents a hydrogen atom or an
alkyl group having 1 to 10 and preferably 1 to 3 carbon atoms such
as a methyl, ethyl or propyl group, R.sup.8 and R.sup.9 each
independently represents a hydrogen atom or an alkyl group having 1
to 20 and preferably 1 to 10 carbon atoms such as a methyl, ethyl,
propyl, isopropyl, butyl, isobutyl, pentyl, hexyl, heptyl or octyl
group. Particularly preferably used herein are, for instance,
benzotriazole compounds represented by the general formula III in
which R.sup.7 represents a methyl group and R.sup.8 and R.sup.9
each represents a 2-ethylhexyl group.
[0028] The content of the benzotriazole compound present in the
grease composition of the present invention preferably ranges from
0.1 to 10% by mass, more preferably 0.3 to 5% by mass and most
preferably 0.5 to 3% by mass on the basis of the total mass of the
grease composition.
[0029] The grease composition of the present invention may comprise
a corrosion inhibitor other than the foregoing benzotriazole
compound, such as succinic acid compound, typical of an alkenyl
succinic acid anhydride, and/or sulfonic acid compound represented
by an alkyl naphthalene-sulfonic acid in combination with the
triazole type one and the amount thereof to be used is desirably
not more than 5.0% by mass on the basis of the total mass of the
grease composition.
[0030] The present invention will hereunder be described in more
detail with reference to the following non-limitative Examples and
Comparative Examples, but the present invention is not restricted
to these specific Examples at all.
EXAMPLES 1 TO 6 AND COMPARATIVE EXAMPLES 1 TO 6
[0031] In these Examples, there were prepared a variety of grease
compositions each comprising a thickening agent, a base oil and
additives specifically listed below and then characteristic
properties thereof were evaluated according to the methods detailed
below:
(Sample Grease Compositions)
Thickening Agent:
Lithium soap (lithium 12-hydroxy-stearate)
[0032] Bentonite modified with an organic compound (organically
modified bentonite)
Base Oil:
[0033] Polyoxypropylene dimethyl ether (n=20): Kinematic viscosity
(at 40.degree. C.): 95 mm.sup.2/s;
[0034] Polyoxypropylene monobutyl ether (n=10): Kinematic viscosity
(at 40.degree. C.): 105 mm.sup.2/s;
[0035] Dioctyl sebacate: Kinematic viscosity (at 40.degree. C.): 12
mm.sup.2/s.
Additives:
[0036] Quinoline compound (trimethyl dihydro-quinoline
oligomer);
[0037] Benzotriazole compound (a mixture comprising
1-[N,N-bis(2-ethylhexyl)-aminomethyl]-4-methyl benzotriazole and
1-[N,N-bis(2-ethylhexyl)-aminomethyl]-5-methyl benzotriazole);
[0038] Phenolic compound (octadecyl
3-(3,5-di-tert-butyl-4-hydroxyphenyl) propionate);
[0039] Succinic acid compound (alkenyl succinic acid
anhydride).
1. Test of Thin Film Under High Temperature and High Humidity
Conditions (Test for Corrosion Resistance)
[0040] A candidate grease composition was applied onto the lower
half of the surface of a copper sheet, a brass sheet or tin-plated
sheet, in a thickness of 2 mm, followed by allowing each sheet to
stand at 60.degree. C., 80% RH for 168 hours and the subsequent
confirmation of whether each test material underwent any external
color change or not. The corrosion resistance of each test material
was evaluated according to the following evaluation criteria:
.largecircle.: The test material is not subjected to any
corrosion;
[0041] x: The test material is in fact subjected to corrosion. 2.
Test for Oxidation Stability
[0042] Method for Determination: This was determined according to
JIS K 2220. 12. (99.degree. C., 100 hours) and was evaluated on the
basis of the following evaluation criteria:
.largecircle.: Less than 50 kPa;
x: Not less than 50 kPa.
3. Olefin-Immersion Test (Compatibility with Material)
[0043] Polypropylene elastomer (having a size of 50 mm.times.5
mm.times.1 mm) was immersed in each sample grease composition (100
g) maintained at 80.degree. C. for 96 hours and then each olefinic
material was inspected for the volume change according to the
following equation: Volume Change(%)=100.times.(A-B)/A
[0044] In the equation, A represents the volume of each elastomer
observed prior to the immersion test and B the volume thereof
observed after the immersion test. Each sample was evaluated on the
basis of the following criteria:
.largecircle.: The sample elastomer has a volume change of less
than .+-.10%;
x: The sample elastomer has a volume change of not less than
.+-.10%.
[0045] The results thus obtained are summarized in the following
Tables 1 and 2: TABLE-US-00001 TABLE 1 Ex. No. 1 2 3 4 5 6
Thickening Agent Lithium hydroxy-stearate 10.0 10.0 10.0 10.0 10.0
Organically modified 10.0 bentonite Base Oil Polyoxypropylene 89.0
86.0 86.0 80.0 86.0 dimethyl ether Polyoxypropylene 86.0 monobutyl
ether Dioctyl sebacate Additives Quinoline compound 0.5 1.0 3.0 5.0
3.0 3.0 Phenolic compound Benzotriazole compound 0.5 3.0 1.0 5.0
1.0 1.0 Succinic acid compound Worked Penetration 280 280 280 280
280 280 Corrosion Resistance .largecircle. .largecircle.
.largecircle. .largecircle. .largecircle. .largecircle. (60.degree.
C., 80% RH .times. 168 hr) Oxidation Stability .largecircle.
.largecircle. .largecircle. .largecircle. .largecircle.
.largecircle. (99.degree. C. .times. 100 hr) Olefin-Immersion Test
.largecircle. .largecircle. .largecircle. .largecircle.
.largecircle. .largecircle. (80.degree. C. .times. 96 hr)
[0046] TABLE-US-00002 TABLE 2 Comp. Ex. No. 1 2 3 4 5 6 Thickening
Agent Lithium hydroxy-stearate 10.0 10.0 10.0 10.0 10.0 Organically
modified 10.0 bentonite Base Oil Polyoxypropylene 87.0 89.0 86.0
86.0 dimethyl ether Polyoxypropylene 86.0 monobutyl ether Dioctyl
sebacate 86.0 Additives Quinoline compound 3.0 3.0 3.0 Phenolic
compound 3.0 3.0 Benzotriazole compound 1.0 1.0 Succinic acid
compound 1.0 1.0 1.0 Worked Penetration 280 280 280 280 280 280
Corrosion Resistance X X X X X X (60.degree. C., 80% RH .times. 168
hr) Oxidation Stability .largecircle. X X .largecircle.
.largecircle. X (99.degree. C. .times. 100 hr) Olefin-Immersion
Test .largecircle. .largecircle. .largecircle. .largecircle. X
.largecircle. (80.degree. C. .times. 96 hr)
[0047] The data listed in the foregoing Tables 1 and 2 clearly
indicate that the grease compositions prepared in Examples 1 to 6
according to the present invention can provide excellent results in
the test of thin film under high temperature and high humidity
conditions, the test for oxidation stability and the
olefin-immersion test, or that these grease compositions are quite
excellent in the corrosion resistance, the oxidation stability and
the compatibility with olefinic material, since the grease
composition of the present invention comprises a polyoxyalkylene
glycol ether as the base oil and a quinoline compound and a
benzotriazole compound as the additives.
[0048] On the contrary, the data listed in the foregoing Tables 1
and 2 likewise clearly indicate that the grease compositions
prepared in Comparative Examples 1 and 4, which are free of any
benzotriazole compound, are inferior in the corrosion resistance,
that the grease compositions prepared in Comparative Examples 2 and
3, which are free of any quinoline compound, are insufficient in
the corrosion resistance and the oxidation stability and that the
grease composition prepared in Comparative Example 5, which makes
use of dioctyl sebacate as the base oil and a succinic acid
compound in place of the benzotriazole compound, are inferior in
the corrosion resistance and the compatibility with olefinic
material. Moreover, it is clear from the foregoing data that the
grease composition prepared in Comparative Example 6 (a
commercially available grease composition), which is free of the
both quinoline type and benzotriazole compounds, is inferior in the
both corrosion resistance and oxidation stability.
* * * * *