WO2010095073A1

WO2010095073A1 - Fuel composition generating a stable flame in particular for decoration, method for preparing same and packaging for said composition

Info

Publication number: WO2010095073A1
Application number: PCT/IB2010/050572
Authority: WO
Inventors: Claude Bernardy
Original assignee: Claude Bernardy
Priority date: 2009-02-17
Filing date: 2010-02-09
Publication date: 2010-08-26
Also published as: FR2942238A1

Abstract

The invention relates to a fuel composition that generates, by combustion with air, a stable flame (8) capable of providing colorations, lighting and decorative effects, and that comprises in mass: at least 40 % of paraformaldehyde of the formula HO (CH2O)n OH, n ranging between 8 and 100; at least 30 % of a liquid containing polar groups having a flash point of between 10 and 200° C, these constituents being homogenised by colloidal grinding; and formulation complements for imparting colours and/or lighting and decorative effects to the flame.

Description

COMBUSTIBLE COMPOSITION PRODUCING STABLE FLAME, IN PARTICULAR FOR DECORATION, PROCESS FOR THE PREPARATION AND PACKAGING THEREOF

The invention relates to a fuel composition producing a stable flame, in particular illuminating and colored, especially for outdoor decoration.

The use of flames produced by combustion of a fuel with the oxygen of the air requires, most often to meet conditions of o security and stability, if the desired duration is between a few minutes and a few hours,

When the ignition temperature of the fuel is lower or equal to the ordinary temperature, it is necessary to limit the flow rate of fuel burned by a suitable mechanism; if, on the contrary, the fuel is lit pAS5 alone, at room temperature, devices used for ignition and maintenance of combustion, for example, ^using a wick whose geometry defines the burned fuel flow.

Safety considerations dictate that the combustor does not risk an extension of combustion, for example, by effusion of an ignited combustible liquid.

The invention makes it possible to produce a flame that is stable under good safety conditions without using the preceding devices by using a pasty, colloidal substance that is easy to ignite and whose combustion rate is determined by the dimensions of the interface between this device. pasty mass el5 atmospheric air.

The colloidal substance forming the fuel composition according to ^the invention is characterized in that it is formed by a mixture containing, by weight:

BU at least 40% paraformaldehyde, oligomer of formaldehyde, of formula HO (CH 2 O) n H ₁ π being preferably between 8 and 100, and at least 30% of a polar group-containing combustible product whose point of melting is less than 8OX, and whose flash point is between 10 and 200 ^° C., preferably between 60 and 140 ^° C. Advantageously, your liquid ύύ polar groups are equipped ^with oxygen atoms.

Generally, the mass ratio of the two main ingredients

[P-formamide] / [polar group-containing liquid] is between 1 and 3, advantageously between 1.6 and 2.0.

The colloidal mixture of the composition is so-so! stabilized paraformaldehyde in the polar group-containing liquid. At least a portion of the polar group-containing liquid may be a glycol ether. At least a portion of the polar group-containing liquid may be a glycol ester. At least a portion of the polar group-containing liquid may be a nitroalkyl. At least a portion of the polar group-containing liquid may be a dialkylamide.

At least a portion of the liquid containing polar groups may have a carbon structure whose number of adjacent carbons is at most equal to 2. The fuel composition may comprise a flame dye additive present at less than 20% of the mass. total.

The coloring additive may be formed by at least one salt selected from the group consisting of lithium, sodium, copper, boron, potassium and strontium salts. Of course, the preceding list of emitted elements is not limiting. Preferably, the dye additive of the flame is present in a proportion of 1 to 3% of the total mass. Advantageously, the coloring salt of the flame is an oxalate.

At least part of the polar group-containing liquid may be a boric acid ester.

The invention also relates to a process for preparing a fuel composition as defined above, characterized in that the grinding of paraformaldehyde in the liquid containing polar groups, produced to form a colloid, is carried out in equipment equipped with a stirring, generally rapid, to micronize the solid and slow stirring to move and homogenize the mass on a macroscopic scale.

The invention also relates to a packaging ^of a fuel composition as defined above, characterized in that the The composition in the form of a paste is placed in a tray-type container fitted with a lid which can only be partially open.

The invention consists, apart from the arrangements set out above, in a number of other provisions including: will be more explicitly discussed below with reference to exemplary embodiments described with reference to the accompanying drawings, but which are not particularly limiting. On these drawings:

Fig.1 is a schematic vertical section illustrating a step of preparing ^a composition according to the invention,

Fig. 2 is a schematic perspective view of a cylindrical box containing the composition being burned

Fig, 3 is a view of a partially open tray containing the composition being burned

Fig. 4 is a view of a tray with a coil of combustible composition. FIG. 5 is a schematic perspective view of another free of conditioning of the fuel composition.

FIG. 6 is a spectrum of a red flame obtained with a fuel composition according to the invention (example 1), the wavelengths expressed in nanometers (nm) being plotted on the abscissa and the relative luminous intensities being plotted on the ordinate, and

Fig.7 is a spectrum of a green flame obtained with a fuel composition according to the invention (Example 2). with abscissae and ordinates similar to Fιg.6,

To prepare the fuel composition of the invention, a mixture is made, for example in a cylindrical receptacle bowl 1 of vertical axis illustrated in Fig. 1, of at least 40% by weight of paraformaldehyde and at least 30% by weight of a liquid containing polar groups of a flash point of between 10X and 200 ⁰ C, preferably between 8O ⁰ C and 140 ^* C. paraformaldehyde is usually available in the form of powder or pearls an average diameter of 2 mm.

A rotary wiper arm 2 is provided to rotate relatively slowly (a few tens of revolutions / minute) about an axis parallel to the geometric axis XX of the container 1 and located at a distance substantially equal to half the radius of the bowl 1. The arm 2 describes a cylindrical surface whose radius is substantially half of the radius of the bowl 1, and scrapes the inner surface on all its height, as well as the bottom. The bowl 1 is rotatably mounted and rotated at a reduced speed (a few tens of revolutions / minute) around its geometric axis XX by means of not shown drive, the entire inner surface of the bowl 1 is scraped by the arm 2, and the mass to be milled passes from one side to the other of the axis XX.

An agitator 3 with a propeller 4a rotating at a high speed, in particular of the order of 3,000 revolutions / minute, radially offset relative to the geometric axis of the receptacle I _1, is provided for shearing the stirred mixture and obtaining homogenization. The propeller 4a is located inside a stator 4b, which surrounds it with a reduced clearance, especially a few tenths of a millimeter.

The scraper arm 2 and the stirrer 3 can be removed from the container 1 at the end of preparation and a thrust device (not shown), for example a piston, can be introduced in the upper part of the container to extrude the pay through an opening lower 5 whose cap 8 has been removed. The dough is collected in a container.

Other devices than that described with reference to Fig.1 may be used, which meet the objectives set out in this application, including obtaining a colloid of the type "so! Of solid finely divided in a liquid. FICJ. 2 shows a cylindrical container 7, of the type trays or boxes, made of aluminum or tinplate, opened and ignited to give a flame 8. The lid 9 of the container may comprise several thin lines of cutting 10, 11 concentric allowing an opening larger or smaller depending on the line chosen. According to the example of FIG. 2, the opening corresponds to a circular line 11 situated radially inwards with respect to line 10. As a result, the combustion will be slower with this opening along line 1 1 than in the case of an opening according to FIG. line 10; the flame, whose volume will be lower, will last longer. It is thus possible to modulate the burn time by modulating the opening determining the contact surface of the paste with the air.

Paraformaldehyde is finely ground in the polar fuel product, used in the liquid state, to gradually form a pasty mass of homogeneous appearance, not flowing. The grinding of the paste, carried out in the wet state, is continued until a sufficient quantity of the solid grains reaches dimensions close to one micron (μm). A good quality result is already obtained when 50% by mass of the grains of solid reaches dimensions smaller than 5 μm.

Fig. 1 illustrates propeller stirring at 3000 rpm to obtain homogenization. Other devices, in particular with rotor and stator to ensure shear, can be used, of various types and referred to generically as "colloid mills". It is not necessary for all of your grains to be reduced to a few microns. Gradually, the mass becomes thick and no longer flows and the whole is stabilized. In general, a "colloid mill" comprises a set of macroscopic homogenization of the payroll, generally at a slow rotation speed 1) and the stirring arm 2) plus a set of microscopic shearing of the particles (constituted in the example of FIG. 1 by the rotor 4a and the stator 4b, with the rotor 4a rotating at the end of FIG. 3000 ovens / minute, and a diameter of 8cm, ^the gap between rotor and stator being of the order of 0.1 to 0.5 mm)

The polar group-containing fuel product may be termed a "polar liquid" because it is used in the liquid state, may be an alcohol, an ether, an ester or a nitroalkyl, or a dialkylamide, or a mixture thereof. this. Chlorinated paraffins, which can also be considered as polar liquids, do not give a soil of high quality. Polar groups with an oxygen atom give much better results than if the polar group consists of one or more halogen atoms.

In each of these cases, after wet grinding, a thick paste without appreciable syneresis is obtained. In comparison, a similar grinding of paraformaldehyde in a non-polar liquid such as a hydrocarbon forms, by grinding, a mixture of liquid and solid which separate by decantation. The pasty substance described by the invention is therefore not simply obtained by the sole effect of grinding but by a combination of the ingredients, because of their mutual affinity.

Are excluded from use of polar group-containing liquid substances whose alkalinity or acidity are too marked and therefore likely to polymerize paraformaldehyde, even storage. For example, primary and secondary amines are to be avoided, while tethanolamine is behaves correctly to form a pasty substance sufficiently stable to be used; in this particular case, the ignition is difficult because of the low volatility of the polar group-containing liquid employed, but easier than the non-combined triethanolamine combined with paraformahehyde. The pasty substance forming the fuel composition defined by the invention constitutes a stabilized assembly for satisfactory combustion, so that the individual characteristics of the constituents are no longer found in the formed combination.

Thus, ethanol, used as a liquid containing polar groups gives a pasty combination less volatile than pure ethanol.

The paraformaldehyde alone burn irregularly and blows the flame by ^the micro-explosions effect due to thermal dépolymérisaîion, which makes it unsuitable for use of fuel. While the pasty substance described by the invention burns regularly without any noticeable release of formaldehyde,

The homogeneity of the pasty mass defined by the ^invention is maintained during combustion, the more easily the liquid containing polar groups used a farthest flash point extremes defined above; the limits being 10 ° and 200 ^° C., the optimal flash point zone is between 60 and 140 ^° C. Thus, Se 2- (2-methoxyethoxy) ethanol, whose flash point is 93.3 × is it appropriate? particularly to the invention as a liquid containing polar groups.

The mass proportion of the main constituents of the colloid varies with the nature of the polar group-containing liquid and the quality of the paraformaiddehyde used; nevertheless, the practical limits of the mass ratio

[paraformaidehyde] / [polar group-containing liquid] are as follows for a satisfactory colloid:

- if this ratio is less than 1, there is a tendency to syπérèse

- If this ratio is greater than 3, the resulting mass is less homogeneous, for the same grinding effort, and the risk increases to find in the colloid, portions of paraformaidhyde insufficiently stabilized. The best quality of the colloid is generally obtained for a mass ratio between 1, 5 and 2.0

In order to find an attractive flame color, at least two conditions must be respected: - The carbon skeleton of the liquid containing polar groups must not have more than two carbon atoms juxtaposed, to avoid giving flame a dominant yellow.

- Component flame dye must be finely dispersed in the colloidal mass for ^the effervescence which forms Get out of the combustion, at the interface between the colloid and the atmospheric air allows sufficient projection of the substance coloring the flame in the flame zone.

The few examples given below, by way of non-limiting example, illustrate the type of formulations allowed by the present invention,

EXAMPLE 1

40 grams of 2- (2methoxy-ethoxy) ethanol (!) Are mixed with 80 grams of 92% (H) paraformaldehyde and 3 grams of lithium (III) oxalate. The whole is finely ground to form a pasty colloid, which lights up easily to form a pretty red flame, without smoke or smell. At the end of combustion, there is almost no solid residue; the combustion was not hindered by residues of this combustion.

Rg.6 illustrates the light spectrum of the red flame obtained, with abscissa wavelengths πm (πaπomères) and relative intensity ordinate. Note a single peak very important for a wavelength of about 870nm, corresponding to the emission of lithium. It thus appears that the colloidal composition virtually rra ^of own show, which is an advantage when it is desired issue colors.

EXAMPLE 2: 30 grams of 2- (2-methoxyethoxy) ethanol (I) are mixed with 10 grams of glycerol borate and a primary alcohol (II) and 60 grams of paraffinic acid (ISI). The whole is finely ground to form a pasty colloid, which lights up easily to form a pretty green flame, without smoke or smell. At the end of combustion, there is almost no solid residue. In this example, the substance (11) acts both as a liquid containing polar groups and a flame dye.

FIG. 7 illustrates the light spectrum of the green flame obtained, with abscissa wavelengths in nm (nanometers) and relative intensity on the y-axis. Note a maximum peak for a wavelength of about 550nm, surrounded by two weaker peaks around 520 nm and 580 nm.

EXAMPLE 3

20 grams of 2- (2-ethoxyethoxy) ethanol (I), 20 grams of nitro-methane (M), 5 grams of anthracene (M1) and 65 grams of paraformaldehyde 96% (IV) are mixed and finely ground to form a pasty colloid that lights up easily to form a pretty, yellowish, scintillating flame with no odor, smoke or residue.

EXAMPLE 4

40 grams of 2- (2methoxy-ethoxy) ethanol (I), 5 grams of copper (II) chloroacetate, and 60 grams of 92% (III) paraformaldehyde are mixed and finely ground to form a pasty colloid which burns with green flame, pulling blue.

The blue shade can be enhanced by replacing copper chloroacetate (II) with copper dichloroacetate or copper trichloroacetate. The blue shade can also be obtained by replacing part of the substance (I) with 2-chloroethanol.

The presence of chlorine intensifies and darkens the blue color of the flame. At the same time, a dark red crest appears on the top of the flame.

EXAMPLE 5 If one adds to formulations of Examples 1 to 4, 2% by weight of finely ground graphite powder (more than 50% of particles having a mean size of less than 5 μm), during the combustion of glittering streaks of golden yellow color.

EXAMPLE 6 If, in Example 1, the lithium (III) oxalate is replaced by sodium oxalate, the flame is yellow-orange. In addition to the six examples given above, tests were performed with, as a liquid containing polar groups, dimethyl-formamide, liquid having the formula: CH3-CO-N (CH3) 2 ^boiling point: 153 ° C flash point: 87 2 ⁰ C

The results obtained were excellent.

Colloidal paste disclosed by the invention is packaged in a sealed manner so as to avoid degradation by the effect of moisture i ^atmosphere or a èvaporatioπ ingredients. The packaging is advantageously chosen to serve as a support during use, in combustion.

Fig.3 shows a metal tray 12, aluminum or tinplate varnished open and fired. It is not always desirable that the entire container be discovered, since the combustion rate is directly related to the interface between the colloidal mass and the atmosphere; a limitation of the open surface makes it possible to reach burn times of a few hours with trays loaded with 300 grams of colloidal mass.

In FIG. 3, the closing cap 13, made of metal sheet, has only been partially disengaged to release an opening 14 corresponding to only a fraction of the section of the tray. The bottom 15 of the tray is sloped towards Ie side of ^the opening 14 to allow the composition to move gradually towards the combustion region of the opening 14.

A first cylindrical tray, similar to the tray 7 of FIG. 2, of circular section with a diameter of 8 cm and a depth of 8 cm, filled with the combustible composition, burns in about two hours. A second tray similar to the first, but having a smaller opening, corresponding to only half of the total section of the tray, burns in four to five hours,

The colloidal paste may also be housed in a tray whose geometry defines a shape and a serpentine flame path 16, as shown in FIG. 4.

In this case, it may be appreciated to use a lid forming a lid of the tray that burns more slowly than the contents of the tray. On ignition, only part of the lid is open, and the rest of the lid opens gradually by the effect of the fiarnme, forming a brake to the combustion. The use of polyamide films treated with fire retardant allows this effect.

The colloidal paste may also be packaged in a polyamide tube, doped with a flame retardant to form a torch held vertically. In order to modulate the given light effects, in particular for a garden torch, it is possible to provide in the tube a succession of cylindrical slices comprising a different coloring substance so that, as the flame is burned, the color will change.

It is also possible to carry out a mixture of different dyestuffs in order to obtain a multicolored flame.

The colloidal paste may also be housed in a vertical planar shape, forming a chosen decorative pattern such as a letter or a heart as indicated at 17 in FIG. Design dimensions of a few tens of centimeters allow outdoor decoration, for festive or advertising or signaling. In this case, a packaging in an open vertical form, the colloidal paste is advantageously modified to prevent casting, by adding thickeners or fibers, for example, 1% of cellulose fiber.

To modulate the light effects, one can provide a conditioning of several colors, whose programming in time is defined by the geometry of the packaging.

The colloidal paste can also be packaged in a flexible tube like glue tube or toothpaste tube. Users can implement it at their convenience by simply pressing the tube to get out the dough, especially in aluminum preforms.

For example, an aluminum center table with many holes, would allow users to play on the desired shapes and / or colors, using different tubes of different colors.

Claims

1. Combustible composition for producing a stable flame suitable for decorative or signaling purposes, or lighting, characterized in that it is formed by a colloidal mixture containing, by mass: at least 40% of paraformaldehyde, oligomer of formaldehyde, of formula HO (CH ₂ O) n H,

and at least 30% of at least one liquid containing polar groups and a fiash point of between 10 ° and 200 ^° C.

2. Composition according to Claim 1, characterized in that the liquid containing polar groups has a flash point of between 60 ° and 140 ^° C.

3. Composition according to claim 1 or 2, characterized in that the polar groups of the liquid are provided with oxygen atoms.

4. Composition according to any one of the preceding claims, characterized in that n is between 8 and 100.

5. Composition according to any one of the preceding claims, characterized in that the mass ratio of the two main ingredients

[paraformaldehyde] / [polar group-containing liquid] is between 1 and 3

6. Composition according to claim 5, characterized in that the mass ratio of the two main ingredients [paraformaldehyde] / [polar group-containing liquid] is between 1.5 and 2.0

7. Composition according to any one of the preceding claims, characterized in that the colloidal mixture is a stabilized paraformaldehyde sol in the polar group-containing liquid. 8. Composition according to any one of the preceding claims, characterized in that at least a portion of the liquid containing polar groups is a glycol ether.

9. Composition according to any one of the preceding claims, characterized in that at least part of the liquid containing polar groups is a glycol ester.

10. Composition according to any one of the preceding claims, characterized in that at least a portion of the polar group-containing liquid is a nitroalkyl.

11. A composition according to any of the preceding claims, characterized in that at least part of the liquid containing polar groups is a dialkylarnide, 12. A composition according to any of the preceding claims, characterized in ^that at least part of the liquid containing polar groups has a carbon structure whose number of adjacent carbons is at most equal to 2.

13. Composition according to any one of the preceding claims. characterized in that it comprises a dye additive of the flame present at a rate of less than 20% of the total mass.

14. A composition according to claim 13, characterized in that dye is formed by at least one salt selected from the group of lithium, sodium, copper, boron, potassium, strontium 15. Composition according to one of the following: Claims 13 or 14, characterized in that the dye additive of the flame is present in a proportion of 1 to 3% of the total mass.

18. The composition according claim 14. characterized in that the salt is a flame colorant oxaiate> 17. Composition according ^to any one of the preceding claims, characterized in that a part at least of the polar liquid consists of a boric alkyl ester.

18. Process for the preparation of a composition according to any one of the preceding claims, characterized in that the grinding of paraformaldehyde in the liquid containing polar groups, produced to form a colloid, is carried out in equipment equipped with a rapid stirring for microπiser the solid and slow stirring and homogenizing for moving the mass to ^the macroscopic scale.

19. Packaging of a composition according to any one of claims 1 to 17, characterized in that the paste composition is disposed in a container-type container with a lid which can be opened only partially.