EP0565715A1

EP0565715A1 - Liquefied gas fuel for generating highly luminous colored flame

Info

Publication number: EP0565715A1
Application number: EP91918904A
Authority: EP
Inventors: Hiroshi Yoshizawa
Original assignee: YOSHIBI CO Ltd
Current assignee: YOSHIBI CO Ltd
Priority date: 1990-04-26
Filing date: 1991-10-24
Publication date: 1993-10-20
Also published as: EP0565715A4; WO1993008245A1; JPH048798A

Abstract

A liquefied gas fuel for generating highly luminous colored flame, which can prevent nozzle clogging because of a remarkable reduction in the dissociation and precipitation of inorganic metal salts, can generate stable colored flame without causing intermittent fading, and can give a colored flame originating in each constituent metal far clearer than what has been observed hereinbefore. This fuel is produced by dissolving a color developing agent comprising at least one compound selected from the group consisting of organic metal salt compounds, organic metal chelate compounds, inorganic metal salt compounds and boric acid compounds and a color developing aid comprising a nitrogenous compound in a flammable gas which vaporizes under atmospheric pressure.

Description

FIELD OF THE INVENTION

This invention relates to a liquefied gas fuel for generating brighter flames of various colors, such as red, yellow, yellowish green, green, blue and purple, at the time of combustion.

BACKGROUND OF THE INVENTION

Heretofore, liquefied gas fuels for generating color flames in which inorganic salt, organic salt and boric acid ester, such as of a specific metal, that create a color flame singly and in combination, when dissolved in an organic solvent, have been proposed. Prior art are exemplified by Japanese Patent Publication Nos. 2322/1976 and 2323/1976. These known liquefied gas fuels are generally used in combustion apparatuses such as gas lighters. Organic salt, inorganic salt and boric acid ester of metal(s) are released, along with liquefied gas, into the atmosphere, when they are being burnt to generate a color flame.
However, inorganic salt, organic salt and boric acid ester of metal used in the prior art have low solubility in organic solvent like alcohol and therefore if mixed with a combustible liquefied gas, the combustibility would be reduced further. Consequently, due to effect of time, temperature, physical impact and physical change ( sudden change from liquid phase to gaseous phase ) at the time of combustion, an organic metal salt or the like would dissociate into end products which clog lighter's nozzle while being emitted. Color flame is therefore only intermittently generated, thus it is impossible to generate a stable color flame.
To this end, after having made studies in an effort to improve the foregoing problems, the present inventors have developed a liquefied gas fuel for generating a brighter color flame by dissolving an emission agents in a combustible liquefied gas vaporizing at atmospheric pressure. An aromatic organic metal compound as an emission primary agent, and oxamic acid ethyl as an emission assistant agent, along with an emission stabilizer comprising at least one selected from the group consisting of xylene, 2-ethylhexanoic acid, and 2-ethylhexylamine. The inventors then filed Japanese Patent Application No. 277517/1985. The present inventors developed another liquefied gas fuel using an organic metal salt compound, an organic chelate compound including metal, an inorganic metal compound and boric acid ester as a color former, along with a surface active agent, and then filed Japanese Patent Application No. 143273/1987. Furthermore, the present inventors developed additionally another liquefied gas fuel using an organic metal salt compound, an organic chelate compound including metal, an inorganic metal compound and boric acid ester as a color former, along with an oxidising agent as color forming assistant, and then filed Japanese Patent Application No. 272819/1988. However, these proposals are inadequate to solve the above-mentioned basic problems.
To solve these basic problems, the present inventors have done further study and developed new liquefied gas fuel using a nitrogen compound as color forming assistant. It was possible to eliminate nozzle clogging and generate a brighter color flame that is much clear, compared to that generated in the prior art.

INDICATION OF THE INVENTION

This invention reveals the existence of a liquefied gas fuel for generating a brighter color flame. A color former is constituted by at least one compound selected from a group consisting of an organic metal salt compound, an organic chelate compound containing metal, an inorganic metal salt compound and boric acid compound Color former is dissolved in a combustible gas vaporizable at atmospheric pressure. Similarly, a color forming assistant agent of a nitrogen compound is also, dissolved in the same combustible gas.
The organic metal salt compounds used in this invention are: barium acetate, calcium acetate, cobalt acetate, cesium acetate, copper acetate, potassium acetate, lithium acetate, molybdenum acetate, sodium acetate, rubidium acetate, strontium acetate, barium cyclohexylbutyrate, cobalt cyclohexylbutyrate, copper cyclohexylbutyrate, lithium cyclohexylbutyrate, sodium cyclohexylbutyrate, strontium cyclohexylbutyrate, calcium cyclohexylbutyrate, cesium cyclohexylbutyrate, potassium cyclohexylbutyrate, molybdenum cyclohexylbutyrate, and rubidium cyclohexylbutyrate.
Examples of the organic chelate compounds containing metal are : barium acetylacetonate, cobalt acetylacetonate, copper acetylacetonate, lithium acetylacetonate, sodium acetylacetonate, strontium acetylacetonate, calcium acetylacetonate, cesium acetylacetonate, potassium acetylacetonate, molybdenum acetylacetonate, rubidium acetylacetonate, barium trifluoroacetylacetone, copper benzoyltrifluoro-acetone, cesium 3-phenylacetylacetone, potassium 2-thenoyltrifluoroacetone, molybdenum 2-thenoyltrifluoroacetone, lithium ethylenediaminetetra-acetate, sodium hexafluoroacetylacetone, strontium dithioacetylacetone, barium dipivaloylmethane, cobalt dipivaloylmethane, copper dipivaloylmethane, lithium dipivaloyl-methane, sodium dipivaloylmethane, strontium dipivaloylmethane, calcium dipivaloylmethane, cesium dipivaloylmethane, potassium dipivaloylmethane, molybdenum dipivaloylmethane, and rubidium dipivaloylmethane.
Examples of the inorganic metal salt compounds are : barium chloride, calcium chloride, cobalt chloride, cesium chloride, cuprous chloride, cupric chloride, potassium chloride, lithium chloride, molybdenum chloride, sodium chloride, rubidium chloride, strontium chloride, barium nitrate, calcium nitrate, cobalt nitrate, cesium nitrate, copper nitrate, potassium nitrate, lithium nitrate, molybdenum nitrate, sodium nitrate, rubidium nitrate, and strontium nitrate.
Examples of the boric acid compounds are : trimethyl borate, tripropyl borate, and triisopropyl borate as the boric acid ester, and barium borate, calcium borate, cobalt borate, cesium borate, copper borate, potassium borate, lithium borate, molybdenum borate, sodium borate, rubidium borate, and strontium borate.
Color generated by the color former depends on the element contained in the color former as follows : Cardinal red results from Li (lithium) ; yellowish green from Ba (barium), orange red from Ca (calcium), green from Cu (copper), bluish purple from Cs (cesium), purple from K (potassium), yellowish green from Mo (molybdenum), yellow from Na (sodium), red from Sr (strontium), blue from Co (cobalt), and dark red from Rb (rubidium).
The nitrogen compound used in this invention may be either organic or inorganic compounds, preferably nitro compound, amine compound and amino compound.
The nitro compound may be, for example, 2-nitroethanol.
The amino compound to be used may be either aliphatic amine or aromatic amine. The following arc examples of the former : methylamine, dimethylamine, trimethyl-amine, ethylamine, symdimethylhydrazine and diethylenetriamine. Aniline and 2-anilinoethanol are examples of the latter. Hydrazine may be also used.
The azocompound are, for example : azomethane, azobenzene and azophenol.
Another nitrogen compound are, for example, nitric ester such as methyl nitrate and ethyl nitrate.
In this invention, various kinds of solvents, such as methanol, ethanol, ethers, tetrahydrofuran or methyl formate, may be used according to need.
The combustible gas vaporizing at atmospheric pressure is characterized by a low-molecular hydrocarbon at normal temperature, such as butane (isobutane, normal butane), propane, LP gas and pentane. Preference is given to use of liquefied butane.
The various compositions to be used in this invention may be prepared by blending at the following proportion :
0.1 to 20 % by weight of a color former,
0.0001 to 10 % by weight of a nitrogen compound,
0 to 40 % by weight of a solvent such as methanol,
40 to 90 % by weight of a combustible gas.

SOME PRACTICAL EXAMPLES WITHIN THIS INVENTION

Following are examples of this invention.

Example 1:

0.1 g of 2-nitroethanol was mixed in 500 cc of methanol to obtain a solution (1). 0.2 g of lithium acetylacetonate was mixed in the solution (1) to obtain a solution (2). 2.2 cc of the solution (2) were added to 2.5 cc of butane, and the resulting mixture was enclosed in a commercially available lighter. When lighter's flame was put on, a clear cardinal red flame was observed.

Example 2:

0.1 g of sodium acetylacetonate was mixed in 20 cc of the solution (1) of Example 1 to obtain a solution (3). 1 cc of the solution (3) was added to 2.5 cc of butane, and the resulting mixture was enclosed in a commercially available lighter. When lighter's flame was put on, a clear yellow flame was observed.

Example 3:

0.2 g of copper acetylacetonate was mixed in 20 cc of the solution (1) of Example 1 to obtain a solution (4). 1 cc of the solution (4) was added to 2.5 cc of butane, and the resulting mixture was enclosed in a commercially available lighter. When lighter's flame was put on, a clear green flame was observed.

Example 4:

0.2 g of cesium acetylacetonate was mixed in 20 cc of the solution (1) of Example 1 to obtain a solution (5). 1 cc of the solution (5) was added to 2.5 cc of butane, and the resulting mixture was enclosed in a commercially available lighter. When lighter's flame was put on, a clear bluish purple was observed.

Example 5 :

0.2 g of potassium acetylacetonate was mixed in 20 cc of the solution (1) of Example 1 to obtain a solution (6). 1 cc of the solution (6) was added to 2.5 cc of butane, and the resulting mixture was enclosed in a commercially available lighter. When lighter's flame was put on, a clear purple flame was observed.

Example 6:

0.1 g of barium acetylacetonate was mixed in 20 cc of the solution (1) of Example 1 to obtain a solution (7). 1 cc of the solution (7) was added to 2.5 cc of butane, and the resulting mixture was enclosed in a commercially available lighter. When lighter's flame was put on, a clear yellowish green flame was observed.

Example 7:

0.1 g of calcium acetylacetonate was mixed in 20 cc of the solution (1) of Example 1 to obtain a solution (8). 1 cc of the solution (8) was added to 2.5 cc of butane, and the resulting mixture was enclosed in a commercially available lighter. When lighter's flame was put on, a clear orange red flame was observed.

Example 8:

0.1 g of strontium acetylacetonate was mixed in 20 cc of the solution (1) of Example 1 to obtain a solution (9). 1 cc of the solution (9) was added to 2.5 cc of butane, and the resulting mixture was enclosed in a commercially available lighter. When lighter's flame was put on, a clear red flame was observed.

Example 9:

0.1 g of 2-anilinoethanol was mixed in 500 cc of methanol to obtain a solution (10). 0.2 g of rubidium acetylacetonate was mixed in 20 cc of the solution (10) to obtain a solution (11). 1 cc of the solution (11) was added to 2.5 cc of butane, and the resulting mixture was enclosed in a commercially available lighter. When lighter's flame was put on, a clear deep red flame with high brightness was observed.

Example 10:

0.1 g of methyl nitrate was mixed in 500 cc of methanol to obtain a solution (12). 0.2 g of lithium dibivaloylmethane was mixed in 20 cc of the solution (12) to obtain a solution (13). 1 cc of the solution (13) was added to 2.5 cc of butane, and the resulting mixture was enclosed in a commercially available lighter. When lighter's flame was put on, a clear cardinal red flame with high brightness was observed.

Example 11:

0.1 g of aniline was mixed in 500 cc of methanol to obtain a solution (14). 0.2 g of barium trifluoroacetylacetone was mixed in 20 cc of the solution (14) to obtain a solution (15). 1 cc of the solution (15) was added to 2.5 cc of butane, and the resulting mixture was enclosed in a commercially available lighter. When lighter's flame was put on, a clear yellowish green flame was observed.

INDUSTRIAL UTILIZATION OF THE INVENTION

According to this invention, it is possible to prevent any clogging of a nozzle such as of a gas lighter and therefore generate a very clear stable color flame. Further, by coloring a colorless flame, it is possible to prevent any accident caused by failing to turn off gas flames due to poor visibility of colorless flames.

Claims

Liquefied gas fuel generating a brighter color flame, composed of color forming agents defined as follow :
(a) A color former includes at least one selected compound from a group of an organic metal salt compound, an organic chelate compound containing metal, an inorganic metal salt compound and boric acid compound. Color former is dissolved in a combustible gas vaporizable at atmospheric pressure.

(b) A color forming assistant agent includes of nitrogen compound, and is similarly dissolved in the same combustible gas.
Liquefied gas fuel mentioned in item 1, comprises nitro compound, amine compound and amino compound instead of nitrogen compound as a color forming assistant agent.