Fuel additive for internal combustion engines and fuel composition

Abstract

Problem A detergent friction modifying agent having both a detergent performance that ameliorates and prevents degradation over time that is caused by deposits in the engine, and a friction reducing effect that lowers frictional resistance in the engine; a fuel additive that improves drivability with a good balance over the entire range of engine speeds, and provides engine characteristics such that, over the entire range of driving speeds, the engine-braking characteristics are such that the feeling of free running will be strongly produced, such that a fuel consumption improvement effect is produced in actual vehicles that is greater than the values produced on the test bench, and which also has storage stability; and a fuel composition containing the same. Solution The present invention is characterized by containing a polyetheramine carboxylic acid salt; the fuel additive of the present invention is added to fuel at 0.5 wt % or less.

Claims

1. A fuel additive for internal combustion engines, wherein the additive comprises a polyetheramine carboxylic acid salt represented by General formula (1),
[R.sub.1COO][R.sub.2O(AO)mXH.sup.+](1) wherein R.sub.1 is a hydrocarbon residue containing 7 to 21 carbon atoms, the polyetheramine moiety having a base component is a compound represented by R.sub.2O(AO)m-X (where R.sub.2 is a hydrocarbon residue containing of 8 to 50 carbon atoms, A is an alkylene group containing 2 to 6 carbon atoms, O is oxygen, m is an integer of 10 to 50, and X is an amino group or a hydrocarbon including a substituted amino group), and X is (C.sub.3H.sub.6NH)nH where n is an integer of 1 to 3.

2. An additive, wherein the additive comprises the additive according to claim 1 and a mineral oil, a synthetic oil, an ester, a polyetheramine or a mixture of any combination thereof.

3. An additive according to claim 2 containing the ester, wherein a ratio by weight / is no less than 1/3 and no greater than 20/3, where is the weight of the carboxylic acid in the polyetheramine carboxylic acid salt, and is the weight of the ester.

4. A fuel composition comprising an additive according to claim 1.

5. A fuel composition according to claim 4, wherein the fuel is gasoline or diesel and 20 ppm to 5,000 ppm of the additive is added.

6. A fuel composition comprising an additive according to claim 2.

7. A fuel composition according to claim 6, wherein the fuel is gasoline or diesel fuel and 20 ppm to 5,000 ppm of the additive are added.

8. A fuel composition comprising an additive according to claim 3.

9. A fuel composition according to claim 8, wherein the fuel is gasoline or diesel fuel and 20 ppm to 5,000 ppm of the additive are added.

Description

DETAIL DESCRIPTION OF INVENTION

(1) The polyetheramine and the carboxylic acid are mixed with complete ratio of salting and the reaction forming the polyetheramine carboxylic acid salt was confirmed by changing the absorption spectrum using an FT/IR made by JASCO Corporation.

(2) Note that, in the description, the term ppm refers to the dosage of the additive in the composition (for example, gasoline), equivalent to 1 mg/Kg=1 ppm.

(3) When the carboxylic acid is added to the polyetheramine and stirred, as a salt gradually forms, the absorption spectrum at 1,720 to 1,700 cm.sup.1 clearly disappears/shifts which range of absorption spectrum comes from the typical CO bond of carboxylic acids. That is to say, the generation of the polyetheramine carboxylic acid salt was clearly confirmed. This salt itself provides stability between additives and provides special properties to the fuel.

(4) That is to say, the polyetheramine carboxylic acid salt shows lubricity but polyetheramine alone doesn't and in particular the salt with an oleic acid reduces engine internal friction much more than friction modifiers found in the past, together with wide range of detergency more than ever.

(5) At the same time, in continuous use, from the intake valve up to the combustion chamber, it can show the effect of keeping clean. In addition to this, as it can suppress the carrier oil, which compensate the detergency at the intake valve deposit etc. at the minimum necessary level, it is more effective to remove the combustion chamber deposit. As the result, it is the polyetheramine carboxylic acid salts show wide range of detergency compared with conventional polyetheramines.

(6) Furthermore, incase of conventional formulations, when a fatty acid ester was added to a detergent (polyetheramine/polyisobutylene amine), a turbidity and a precipitation occurred within several months to one year or so. In contrast, the polyetheramine carboxylic acid salt of the present invention, or a formulation containing a detergent such as a polyetheramine etc. which contains this, can suppress the occurrence of turbidity and precipitation significantly, when a fatty acid ester is added. Consequently, it is possible to make the more flexible formulation freely, while maintaining or improving the specific detergency of polyetheramines.

(7) About the evaluation method of the improving fuel economy technology:

(8) the conventional evaluation of the improving fuel economy technology for fuel additives and fuels containing fuel additives has been carried out just only attention to the reduction of the friction loss of the engine. However, because of the lack of the attention to finding the engine property change, it is hardly to say that the actual fuel economy has always been improved.

(9) On the other hand, after the actual driving vehicle test has been confirmed repeatedly on the appropriate driving method (identical driving conditions, such as average speed) corresponding to the engine property change caused by gasoline containing polyetheramine carboxylic acid salts, especially containing polyetheramine oleic acid salt, the fuel economy improvement effect, that has never been achieved, was obtained.

(10) Then, a lot of combinations with various friction modifiers were tested so that the driver would more naturally and unconsciously drive a car to fit its engine property which was created by reduction of the engine internal friction while considering to the effect of the drive feeling caused by engine property changes.

(11) As a result, it was discovered that, in order to achieve better actual fuel economy improvement, rather than simply obtaining further reduction of the engine internal friction, adding the fatty acid ester resulted in a change in the engine-braking feel, such that, particularly at low speeds, a free running sense (free-running impression) was strongly felt just before releasing the accelerator pedal.

(12) The increase of the free-running sense just before and just after releasing the accelerator pedal unconsciously leads driving wherein the driver releases the accelerator pedal earlier than usual. Because of no engine-braking effect even if easing up on the accelerator, if the accelerator pedal is released at the same timing as usual, the free driving distance becomes longer than expected, thus the brake pedal will be stepped on earlier, or strongly just before stopping, and the driver naturally feels uncomfortable. Consequently, by strongly producing this feel with the additive combination according to the present invention, the driver will unconsciously be caused to release the accelerator pedal at an earlier timing than in cases where there is no additive, or with fuel containing a conventional additive formulation. It is possible to greatly improve actual fuel consumption by way of guiding the driver in such a manner as unconsciously earlier releasing accelerator pedal.

(13) Then, in order to make the driver feel the free-running sense strongly, it is desirable that the ratio by weight of the fatty acid ester to the carboxylic acid moiety in the polyetheramine carboxylic acid salt is in the range between or more and 20/3 or less, and preferably or more and 20/3 or less. Even if 20/3 is exceeded, this sense will not be strengthened. What is more, deposits tend to form at the intake valves, and in the combustion chambers, etc. At less than , the subtle engine-braking feel fades out, and thus this does not lead improvements in actual fuel consumption.

(14) When taking a balance of detergency and improvement of actual fuel economy performance, the detergency can be improved by increasing the polyetheramine content.

(15) In this case, a polyetheramine may be added, that is the same or different molecular structure of the polyetheramine carboxylic acid salt, and in this case, by adding a polyetheramine having a different molecular structure so as to take advantage of the characteristics of the molecular structure of the polyetheramine, it is also possible to make a broader range of the detergency than the detergency from a single polyetheramine salt alone.

(16) In particular, in case of the treatment such as one-tank clean up (to remove deposits by adding a detergent additive at high dosage into a fulfilled fuel tank) which removes the engine internal deposits, it is preferred to use polyetheramine carboxylic acid salts mixed with polyetheramines for immediate effect compared with using polyetheramine carboxylic acid salts alone.

(17) In the case of diesel fuel, polyetheramine detergents as used in genuine products from many automakers are restricted exclusively for gasoline (Mazda's Genuine Product PEA and the like). That is to say, it has been stated that polyetheramine detergent are not suited for diesel engines. However, when fatty acid salts among from polyetheramine carboxylic acid salts, more preferably polyetheramine oleic acid salts are added into diesel fuel, the disadvantages are not found at all, and it is effective on removing the sludges form in all fuel lines of the fuel injection system, and at the same time it is possible to improve the lubricity of the diesel fuel.

(18) Furthermore, in case of the common-rail diesel engine as the latest diesel engine, fuel adhesion on the cylinder wall caused by pre-injection etc. increase the friction between piston rings and cylinder walls. However, it can not only prevent friction increase but also reduce it. And the better fuel economy can be achieved than that of the conventional formulation with fatty acids and fatty amine.

(19) Note that, detergents (regardless of the type or molecular structure) may be added to the additives or fuel compositions described above, and other additives that can be used in fuels as different friction modifiers, such as amines, amides, esters, and fatty acids, as well as corrosion inhibitor, dispersant, and solubilizing agents may be added, and in particular, with consideration for the handling of additives, these may be diluted with a solvent in order to reduce viscosity and facilitate adjustment of the dosage, there being no restrictions in terms of combinations with any other additives.

(20) Hereafter, preferred embodiments of the present invention are described using examples.

Example 1

(21) <Evaluation of Detergency>

(22) Polyetheramine, the same polyetheramine salted with fatty acids containing no less than 50% of an oleic acid as a polyetheramine calboxylic acid salt, and polyetheramine with 10%, 25% of a nonylphenol butylene oxide polymer as the carrier oil, and 10% of the same polymer added to the polyetheramine carboxylic acid salt, were added to regular gasoline available in the market at the equivalent of 2,500 ppm as polyetheramine based in each, and the results of detergency against intake valve deposits and combustion chamber deposits are summarized in Table 1. A further two types of samples were evaluated in which the equivalent of 500 ppm of polyetheramine were added.

(23) TABLE-US-00001 TABLE 1 Detergent test 1 Deposit removal status Sample Combustion No. Additive composition Intake valve chamber 1-1 polyetheramine 1-2 polyetheramine + carrier oil 10% 1-3 polyetheramine + carrier oil 25% 1-4 polyetheramine carboxylic acid salt 1-5 polyetheramine carboxylic acid salt + carrier oil 10% 1-6 sample 4 + polyetheramine 1-7 sample 5 + polyetheramine legend : excellent, : good, : poor

(24) In the evaluation described above, the Subaru generator SGi25S was used. Before evaluation for each candidate, deposits were formed by 50 hours operation with gasoline which contains 3% of engine oil, and then, evaluation was carried out for 50 hours by means of changing the load every one hour. Note that Synthesis Example 1 described in JP-06-062965-B was used as the polyetheramine.

Example 2

(25) <Evaluation of Dissolution of Intake Valve Deposits and Combustion Chamber Deposits>

(26) Deposits from the IVT and CCD were immersed in undiluted solutions of the polyetheramine, the polyetheramine oleic acid salt and a polyetheramine caprylic acid salt at different temperatures, and the degree of dissolution was evaluated.

(27) The polyetheramine and the salt thereof ([R.sub.2O(AO)m-XH.sup.+]) used in the evaluation was that with the best balance wherein R.sub.2=13, A=4 (C.sub.4 alkylene group), m=20, and for X, n=1 was used.

(28) TABLE-US-00002 TABLE 2 Detergent test 2 IVD (intake CCD (combustion valve deposit) chamber deposit) evaluation evaluation Undiluted Undiluted solution solution Sample Undiluted solution temperature temperature No. composition 60 C. 120 C. 60 C. 120 C. 2-1 PEA 2-2 PEA oleic acid salt 2-3 PEA caprylic acid salt legend : excellent, : good

Example 3

(29) <Evaluation of the Fuel Consumption Improvement Effect of Polyetheramine Carboxylic Acid Salts>

(30) actual fuel consumption was measured by using various different engines with polyetheramine, polyetheramine carboxylic acid salts (crude oleic acids containing fatty acid mixture as the carboxylic acid), fatty acids (the same crude oleic acids containing fatty acid mixture in the same amount in the carboxylic salts), and polyetheramine cyclohexanoic acid salt at the equivalent of 1,000 ppm (as the dosage in regular gasoline) of polyetheramine. A polyetheramine wherein R.sub.2=13, A=4 (C.sub.4 alkylene group), m=20, and for X, n=1 was used.

(31) TABLE-US-00003 TABLE 3 Comparison of fuel consumption with polyetheramine carboxylic acid salt salts Sample Average fuel consumption No. Additive composition improvement rate 3-1 polyetheramine 0% 3-2 polyetheramine fatty acid salt 6.30% 3-3 fatty acid 2.90% 3-4 polyetheramine cyclohexanoic 0.80% acid salt

(32) The values in Table 3 are average values, primarily measured by driving on the highways, with a 150 cc single-cylinder engine, a 250 cc four-cylinder engine, a 1300 cc four-cylinder engine, a 1,300 cc direct-injection engine, and a 2,000 cc four-cylinder turbocharged engine.

(33) The engine internal deposits of each vehicle were removed in advance with polyetheramine, and the tests were performed after determining the standard fuel consumption without additives. In all cases, the fuel used was regular gasoline that did not contain additives. These are average values for each vehicle making a 100 km two-way trip at 20 to 25 times.

Example 4

(34) From among the polyetheramine carboxylic acid salts, the salts with fatty acids containing 90% or more of oleic acid which shows the higher fuel consumption improvement effects and the salts with fatty acids containing 99% or more of caprylic acid were used and fuel consumption measurements were performed A polyetheramine wherein R.sub.2=13, A=4 (C.sub.4 alkylene group), m=20, and for X, n=1 was used The dosage of each sample was equivalent to 1000 ppm of polyetheramine (as the dosage in regular gasoline).

(35) TABLE-US-00004 TABLE 4 Fuel consumption improvement effect with polyetheramine fatty acid salts Sample Average fuel consumption No. Additive composition improvement rate 4-1 PEA 0% 4-2 PEA oleic acid salt 7.20% 4-3 PEA caprylic acid salt 1.10%

(36) In the test described above, the values were obtained by driving suited to the changes in engine behavior with the same vehicles as in Example 2. In terms of the polyetheramine salts, salts were made with the same polyetheramine as in Example 3, and fatty acids containing 90% oleic acid, or 99% caprylic acid, respectively.

(37) The polyetheramine fatty acid salts have a fuel consumption improvement effect, but with C.sub.19 and higher fatty acids, the solubility of the additive itself is insufficient and some precipitates. Likewise, among fatty acid salts containing oleic acid, the higher concentration of the oleic acid is preferable. That is to say, it was found that polyetheramine oleic acid salts had the greatest fuel economy improvement effect.

Example 5

(38) <Evaluation of Differences in Fuel Economy Improvement Rates in High-Speed Driving and on Ordinary Roads where Vehicles Repeatedly Start and Stop>

(39) However, in cases of driving in cities where acceleration and deceleration is repeated, when polyetheramine fatty acid salts are used, it improves the engine response more, and the fuel economy improvement rates may not s be always the same as that in high-speed driving due to stepping on the accelerator pedal more often and the like. Hereafter, from among Example 4, two types of vehicles, with a fuel-efficient engine and a high power type engine were compared. The salt was made from a fatty acid containing no less than 90% oleic acid and the same polyetheramine as in Example 3. The dosage as the polyetheramine content was 500 ppm w/w (dosage in regular gasoline).

(40) TABLE-US-00005 TABLE 5 Evaluation of changes in fuel consumption improvement rates due to driving conditions (average fuel consumption improvement rate with Honda PCX150/Yamaha Majesty S) Driving category Fuel consumption improvement rate high-speed driving/300 km/average 7.10% in-town driving/280 km/average 5.80%

(41) As shown by the results in Table 5, in in-town driving, where the accelerator pedal is frequently turned on and off, the fuel consumption was found to improve less than expected.

Example 6

(42) <Evaluation of the Change in Engine-Braking Free-Running Feel at Low Speeds, and the Effect on Actual Fuel Consumption, with Fatty Acid Esters>

(43) Based on the evaluation in Example 5, minimization of the engine-braking effect just before gas pedal release at lower speeds was studied.

(44) Specifically, esters were added to the polyetheramine carboxylic acid salt.

(45) Samples were made by varying the ratios at which esters were added, which is a ratio by weight of /, where the weight of the ester is , and where the weight in terms of the carboxylic acid in the polyetheramine carboxylic acid salt is .

(46) An ester containing no less than 95 wt % of glycerol monooleate was used. A polyetheramine oleic acid salt was used as the polyetheramine carboxylic acid salt. The dosage of the polyetheramine oleic acid salt was 500 ppm w/w in all cases. The evaluation target was the free-running feel.

(47) TABLE-US-00006 TABLE 6 Engine-braking evaluation and actual fuel consumption Additive wherein glycerol monooleate was added to Fuel polyetheramine Free-running feel evaluation consumption Sample oleic acid salt Speed (per hour) improvement No. / value 30 km 40 km 60 km 80 km rate 6-1 0 5.80% 6-2 1/2 X 5.60% 6-3 3/3 6.10% 6-4 9/3 7.40% 6-5 21/3 7.40% legend : excellent, : good, : fair, X: poor

(48) For the evaluation vehicles, a 1,300 cc four-cylinder 129 kW high-power engine motorcycle; a 1,300 cc, 14:1 high compression ratio direct-injection engine; a 2,000 cc turbo, 149 kW manual vehicle; a 250 cc four-cylinder motorcycle; and a 150 cc scooter were used, and the results for the vehicles were comprehensively evaluated.

(49) A polyetheramine wherein R.sub.2=13, A=4 (C.sub.4 alkylene group), m=20, and for X, n=1 was used.

Example 7

(50) <Engine Deposit Suppressant Effect Rresulting from Additives that Combine Polyetheramine Carboxylic Acid Salts, Esters and Polyetheramines>

(51) When a glycerol monooleate (concentration: 95 wt %) as the ester was mixed at the aforementioned / of 20/3 or more, the detergency of the polyetheramine carboxylic acid became worse and the intake valve deposits and the combustion chamber deposits increased drastically and therefore there was no advantage to adding this in an excessive amount.

(52) Conversely, if the overall dosage mixed with polyetheramine carboxylic acid salt and the ester is increased more than necessary, it does not mean that the detergency is improved. Here, it was discovered that, in such cases, it is possible to compensate for the degradation of the detergency.

(53) TABLE-US-00007 TABLE 7 Effects of fatty acid ester on CCD and detergency of polyetheramine fatty acid salts (CCD: combustion chamber deposit) evaluation) Mixture of polyetheramine oleic acid salt and CCD (combustion Sample glycerol monooleate Polyetheramine chamber deposit) No. / value addition evaluation 7-1 0 no 7-2 9/3 no 7-3 20/3 no 7-4 21/3 no 7-5 20/3 yes legend : excellent, : good, : fair

(54) A Subaru generator was used as the evaluation equipment. The evaluation was carried out with regular gasoline with 1,500 ppm w/w of a polyetheramine oleic acid salt as the polyetheramine carboxylic acid salt. Further, the amount of additionally added polyetheramine was 500 ppm w/w with the above regular gasoline containing the polyetheramine oleic acid.

(55) Here, it was found that combustion chamber deposits, CCD, start to increase when the / value began to be exceeded 20/3. Furthermore, in terms of the impact on the engine-braking feel, even if the / value was increased beyond this, there was no change, and thus there is no advantage to adding the ester and the polyetheramine fatty acid salt in excess of 20/3. As the / value is getting close to 20/3, the CCD gradually increased. Sample No. 7-5 is one wherein a single PEA, polyetheramine, was additionally added, and it was found that the deterioration of the CCD was ameliorated by adding the polyetheramine, and thus it was possible to enhance detergency for more diverse systems.

(56) A polyetheramine wherein R.sub.2=13, A=4 (C.sub.4 alkylene group), m=20, and for X, n=1 was used.

Example 8

(57) <Storage Stability Tests>

(58) Polyetheramine carboxylic acid salt alone has many advantages, but in order to provide a variety of performance, it may be combined with ester-based friction modifiers and amine-based or amide-based additives.

(59) With conventional formulations, when ester-based additives were present together with amine compounds, the stability became worse, and in particular, when combined with detergents (polyetheramines, polyisobutyl amines and the like), turbidity occurred and precipitation is produced. and particularly in the case of additives for the aftermarket, it is not possible to store long-term, and not fit for the aftermarket. For this reason, in order to produce multi-functional performance, the formulations with detergents were restricted.

(60) In this regard, it was found that the formulations that contain polyetheramine carboxylic acid salts together with ester-based additives can prevent turbidity and precipitation etc., and it became possible to make a free combinations.

(61) For the storage stability tests, polyetheramine carboxylic acid salts were made with various carboxylic acids, i.e. oleic acid (total carbon number: C.sub.18), caprylic acid (total carbon number: C.sub.8), behenic acid (total carbon number: C.sub.22), cyclohexanoic acid (total carbon number: C.sub.7). As the ester, glycerol monooleate was blended in at the aforementioned / value of 3 (9/3).

(62) Addition to the above candidates, single polyetheramine was added to each at approximately 50 wt % of the polyetheramine in the polyetheramine carboxylic acid salt and tested. Furthermore, Polyisobutylene amine alone at, the same total base number as the polyetheramine (Sample 8-10), and this with polyetheramine oleic acid salt at a ratio by weight of 1:1 (Sample 8-11) were also evaluated. Glycerol monooleate was added to all of these samples at the / value of 3 (9/3).

(63) TABLE-US-00008 TABLE 8 Storage stability tests Storage stability Addition of After Sample approximately / one After 3 No. Main additives 50 wt % PEA value month months After one year 8-1 PEA no 3 haze precipitation decomposition and precipitation 8-2 PEA oleic acid no 3 clear clear clear salt 8-3 PEA caprylic no 3 clear clear clear acid salt 8-4 PEA behenic no 3 clear slight haze haze acid salt 8-5 PEA no 3 clear clear clear cyclohexanoic acid salt 8-6 PEA oleic acid yes 3 clear clear clear salt 8-7 PEA caprylic yes 3 clear clear clear acid salt 8-8 PEA behenic yes 3 clear haze precipitation acid salt 8-9 PEA yes 3 clear clear slight haze cyclohexanoic acid salt 8-10 polyisobutylene no 3 haze precipitation precipitation amine 8-11 polyisobutylene no 3 clear clear clear amine + PEA oleic acid salt PEA: polyetheramine

(64) When carboxylic acid containing the total number of carbon atoms of 22 or more is used, the solubility of the polyetheramine carboxylic acid salt itself becomes inferior. At the same time the effect of preventing internal reactions is getting weak. The effect of preventing precipitation by adding the polyetheramine carboxylic acid salt is effective not only for polyetheramine, but also for polyisobutylene amine.

Example 9

(65) <Overall Fuel Consumption Evaluation>

(66) Just polyetheramine alone is added at 25 wt % into polyetheramine oleic acid salt and into this, as the ester, glycerol mono oleate (GMO) was also added at the ratio by 3 times of the oleic acid in the salt, and this is added into gasoline at a ratio by weight of 500 ppm with respect to the gasoline, and this was taken as Sample 9-1. Sample 9-1 without containing the glycerol mono oleate was taken as Sample 9-2. Evaluation was performed for the various gasolines with oleic acid alone (Sample 9-3), glycerol mono oleate alone (Sample 9-4), a mixture of these (Sample 9-5), a mixture of polyetheramine that is not a salt with glycerol mono oleate (Sample 9-6) and further a composition wherein oleylamine, as a friction-modifying fatty acid amine, was added in an amount that was the same as that of the glycerol mono oleate (ester) (Sample 9-7).

(67) In terms of the evaluation method, the evaluation was performed using the additives (Sample 9-1 to Sample 9-7) on distances of 100 km on the highway and 150 km on ordinary roads, 10 times each, with gasoline without additives as reference.

(68) Average values for actual fuel consumption improvement rates were obtained. In terms of the test vehicle, engines are a fuel-efficient 150 cc single-cylinder engine; a 1,300 cc 176 horsepower, natural aspiration four-cylinder engine; and a 1,300 cc direct injection, common-rail, four-cylinder engine with a compression ratio of 14:1 and the like.

(69) TABLE-US-00009 TABLE 9 Overall fuel consumption evaluation results Average actual fuel Sample consumption No. Additive composition improvement rate 9-1 polyetheramine oleic acid salt + GMO 7.20% 9-2 polyetheramine oleic acid salt 4.80% 9-3 oleic acid 1.80% 9-4 GMO 2.90% 9-5 oleic acid + GMO 1.00% 9-6 polyetheramine + GMO 3.20% 9-7 polyetheramine + GMO + oleylamine 3.10% NB: GMO = glycerol mono oleate

(70) It was found that the composition wherein a suitable ester was combined with the polyetheramine oleic acid salt (Sample 9-1) achieved improvement in fuel consumption greater than the composition of the polyetheramine oleic acid salt alone (Sample 9-2). Further, it was found that the effects were incomparably superior to those of the conventional composition of oleic acid alone (Sample 9-3), the ester alone (Sample 9-4), or the mixture of these (Sample 9-6). Next, it was found that, a drastic fuel consumption improvement effect was achieved, even in comparison with the composition containing the polyetheramine and the ester, which are said to have a synergistic effect (Sample 9-6) and with the conventional compositions containing oleylamine and the like was added (Sample 9-7).

Example 10

(71) <Evaluation of the Fuel Consumption Improvement Effect>

(72) In order to further clarify the effect of the polyetheramine carboxylic acid salt, in order to confirm how fuel consumption is influenced in terms of each of polyetheramine and carboxylic acid, the influences on fuel consumption and other effects of polyetheramine oleic acid salt, polyetheramine, and oleic acid alone were tested.

(73) Fuels containing polyetheramine at 200 ppm and 400 ppm were taken as Samples 10-1 and 10-2, and fuel containing fatty acids with 80% of oleic acid concentration at 50 ppm as the carboxylic acid, was taken as Sample 10-3, and the fuel consumption improvement effect was studied by comparison with fuels without these additives.

(74) TABLE-US-00010 TABLE 10 Fuel consumption improvement effect of polyetheramine and oleic acid Fuel consumption Sample Additive improvement effects in No. (parts per million by weight in fuel) high-speed driving 10-1 polyetheramine (200 ppm) 0.00% 10-2 polyetheramine (400 ppm) 0.00% 10-3 fatty acid (50 ppm) 2.20%

(75) In terms of the evaluation method, a drive computer was used for a 1,300 cc four-cylinder 176 horsepowered large motorcycle, and the average values during driving 300 Km under the same conditions were used. The same polyetheramine as in Example 3 was used.

(76) In addition, a composition was made so that 50% of the oleic acid would form a salt with the polyetheramine, and this was added into gasoline fuel at 250 ppm by weight (corresponding to 225 ppm in polyetheramine oleic acid salt and 25 ppm of oleic acid) and this was taken as Sample 11-1, while the polyetheramine oleic acid salt was added into gasoline fuel at 450 ppm by weight (this salt is 100% of the 50 ppm of oleic acid had formed a salt with the polyetheramine) and this was taken as Sample 11-2, and these were evaluated. In terms of the evaluation method, a drive computer was used for a 1,300 cc four-cylinder 176 horsepowered large motorcycle, and the average values during driving 300 Km under the same conditions were used. The same polyetheramine as in Example 3 was used.

(77) TABLE-US-00011 TABLE 11 Fuel consumption effects of fatty acid salts and fatty acids Fuel consumption Sample Additive improvement effects No. (parts per million by weight in fuel) in high-speed driving 11-1 polyetheramine oleic acid salt + fatty 3.40% acid (250 ppm (corresponding to 225 ppm + 25 ppm)) 11-2 polyetheramine oleic acid salt 4.30% (450 ppm)

(78) From these results it was found that the composition wherein 100% of the oleic acid had formed a polyetheramine oleic acid salt (Sample 11-2) had a greater fuel consumption improvement effect than the composition in which the oleic acid formed a polyetheramine oleic acid salt at a ratio of 50% (Sample 11-1).

(79) It is judged that, rather than a synergistic effect being produced when the oleic acid and the polyetheramine are both present, in fact the polyether oleic acid salt itself produces the fuel consumption improvement effect. That is to say, the polyetheramine carboxylic acid salt itself can be said to produce the fuel consumption improvement effect.

Example 11

(80) <Effect of Reducing Mechanical Noise of the Engine>

(81) The polyetheramine carboxylic acid salt greatly reduces mechanical noise of the engine, and particularly noise around the valves.

(82) Meanwhile, with direct-injection, high-compression injection engines which have become more common in gasoline vehicles in recent years, the sound of the fuel injector and the like can be heard to a considerable extent.

(83) However, by adding the polyetheramine carboxylic acid salt (Sample 12-2), an effect of greatly reducing these noises is achieved, and more quiet engine performance can be produced. Further, a composition wherein an ester containing glycerol mono oleate 50% and glycerol dioleate 40% is added to the polyetheramine carboxylic acid salt with a / value of 10/3 (Sample 12-3) produced an effect of further reducing mechanical noise.

(84) TABLE-US-00012 TABLE 12 Noise effect Maximum Minimum Sample noise noise No. Additive level (dBA) level (dBA) 12-1 no additives 76.5 73.2 12-2 polyetheramine fatty acid salt 70.1 68.5 12-3 polyetheramine fatty acid 69.5 68 salt + ester

(85) In terms of the evaluation method, a 1.3 L, direct-injection, gasoline engine with a high compression ratio of 14:1 was used, and measurements were carried out at around 30 cm from the top of the engine.

(86) A polyetheramine wherein R.sub.2=13, A=4 (C.sub.4 alkylene group), m=20, and for X, n=1 was used, and a salt was made with a fatty acid containing 80% oleic acid, which was added to gasoline so as to produce a concentration of 500 ppm, and this was evaluated.

(87) A composition of 50% glycerol monooleate, 40% glycerol dioleate and the remaining being 10% triglycerol was used as the ester.

Example 12

(88) <Evaluation for Diesel: Complete Test of Engine Stalling due to Sludge Built Up in the Suction Control Valve>

(89) These are the results of adding the polyetheramine carboxylic acid salt that demonstrated good results in gasoline engines to diesel fuel at 1,500 ppm and driving a Toyota Hiace 200 Series with a common-rail diesel engine using the above fuel. This tested car frequently had engine stalls at the start.

(90) TABLE-US-00013 TABLE 13 Changes in the number of engine stalls (effect of improving initial problem in suction control valve) Sam- Addition of ple additive to Additive Number of Driving No. vehicle dosage stalls distance 13-1 vehicle before 0 ppm 14 times 0 km using additive (number of times before test) 13-2 addition of 1,500 ppm 0 times 0 km to 2,000 km additive (first time) 13-3 addition of 250 ppm 0 times 2,000 km to 7,000 km additive (second time) 13-4 no additives 0 ppm 2 times 7,000 km to 9,000 km

(91) In terms of the evaluation, a Toyota Hiace 200 Series, 2.5 L common-rail diesel vehicle was used as the test vehicle. The diesel fuel used for both Samples 13-1 and 13-4 is market available diesel fuel.

(92) The first evaluation (Sample 13-2) was one in which, for the polyetheramine carboxylic acid salt, a salt was made using a composition including no less than 80% oleic acid, and an additive containing this salt was added to market available diesel fuel at an additive dosage of 1,500 ppm. Engine stalling occurrence was evaluated by driving for 2,000 km. Engine stalling entirely ceased to occur in this driving, and when 5,000 km was subsequently driven with an additive dosage of 250 ppm, engine stalling likewise did not occur.

(93) That is to say, the malfunction caused by sludge that was the cause of engine stalling due to suction control valve failure was improved and it was possible to prevent engine stalling. Note that sludge is formed primarily due to the composition of diesel fuel.

(94) Thereafter, the additive dosage was reduced to 250 ppm w/w and test was performed for 5000 km as a second evaluation, engine stalling did not occur.

(95) Subsequently, during driving for 2,000 km with market available diesel fuel, engine stalling reoccurred close to 2,000 km. Upon immediately switching to diesel fuel containing the additive, it was possible to avoid the engine stall symptoms immediately thereafter.

(96) From the foregoing facts it can be said that, at high dosage, polyetheramine oleic acid salt removes sludge on the suction valve, and prevents the formation of sludge, and at low concentrations, it prevents the formation and adhesion of sludge, and thus can prevent occurrence of engine stalls. Meanwhile, when changing the diesel fuel with additives back to the market available diesel fuel without additive, the trouble occurred again, thus it found that the diesel fuel with polyetheramine oleic acid salt demonstrated the performance which could not found in market available diesel fuel.

(97) As above, by way of evaluation tests using actual vehicles which were already known to have problems, when the diesel fuel containing the additive from the present invention is used, it was evidenced that both (1) detergent performance and (2) lubricity are provided, such as (1) sludge removing properties and, (2) improvement and prevention of the malfunction of the suction control valves caused by insufficient lubricity of the diesel fuel and sludge formation by improved diesel fuel lubricity.

Example 13

(98) <Fuel Consumption Improvement Effect in Common-Rail Diesel Engines>

(99) TABLE-US-00014 TABLE 14 Fuel consumption improvement at fixed speed Sample No. Additive Dosage 40 km/hour 80 km/hour 14-1 polyetheramine oleic 1,500 ppm 7.30% 6.80% acid salt

(100) In terms of the evaluation method, the auto cruise function on a Peugeot 307 HDi 137 was used, and driving in the same location, the amount of fuel consumption was measured with a drive computer. Note that, by driving at the same road section 5 times, the average value was found so as not to be influenced by wind or the like.

(101) As a result of this evaluation test, it was found that a fuel consumption improvement effect and a cleaning effect were achieved in the same manner as with gasoline vehicles, even with a common-rail diesel.

CONCLUSIONS

(102) The effects of the polyetheramine carboxylic acid salt are multifold, covering detergent properties, storage stability, fuel economy improvement and changes in engine characteristics.

(103) These properties are largely dependent mainly on the type of carboxylic acid.

(104) The following table summarizes, in a manner that is easy to understand, the key performance for additives containing the polyetheramine carboxylic acid salt according to the present invention and conventional additives.

(105) TABLE-US-00015 TABLE 15 Noise Sample Storage Energy reduction No. Additive stability Detergency savings effect 15-1 PEA X X 15-2 PEA caprylic acid X salt 15-3 PEA oleic acid salt 15-4 PEA X cyclohexanoic acid salt 15-5 PEA caprylic acid salt + ester 15-6 PEA oleic acid salt + ester 15-7 PEA X cyclohexanoic acid salt + ester 15-8 PEA + ester X 15-9 PEA oleic acid salt + ester + PEA PEA: polyetheramine legend : excellent, : good, : fair, X: poor

(106) It can be said that, from among the polyetheramine carboxylic acid salts, polyetheramine oleic acid salts demonstrate excellent performance in many respects

(107) Even with combination with esters which significantly improve practical fuel consumption by changing the drive feel (free-running feel) to the driver, the additives do not cause internal reactions or the like, thus it allows to make formulations more freely, as the results it is possible to achieve energy-saving effects that could not be obtained conventionally.

(108) At the same time, even with the balance of detergent performance, it is possible to make more highly stable formulations.

(109) Furthermore, detergent performance and fuel consumption improvement effect are also achieved with diesel fuel.

(110) Note that regular gasoline was used for all the evaluation tests described above.

(111) Also in the evaluation tests described above, when not specifically stated, the polyetheramines are the polyetheramine salts used were all those wherein R.sub.2=13, A=4 (C.sub.4 Alkylene group), m=20, and for X, n=1.

(112) Furthermore, derivatives of branched tridecanol, which is to say (CH.sub.3CH(CH.sub.3)((CH.sub.2CH(CH.sub.3)).sub.2CH(CH.sub.3)(CH.sub.2).sub.2OH), synthesized by the oxo process, can be used for the polyetheramine (PEA) where R.sub.2=13 (C.sub.13).

(113) Furthermore, in terms of examples of the structural formula of this polyetheramine (PEA), an example of a structural formula wherein R.sub.2=13, A=4 (C.sub.4 alkylene group), m=20, and for X, n=1 is as follows.

(114) ##STR00001##

(115) Furthermore, in terms of the polyetheramine (PEA), substances where R.sub.2=8 (C.sub.8) including octanol, which is to say n-octanol (CH.sub.3(CH.sub.2).sub.7OH) and 2-ethylhexanol (CH.sub.3(CH.sub.2).sub.3CH(C.sub.2H.sub.5)CH.sub.2OH) were used.