EP0181270A1 - Process and apparatus for the preparation of an upholstering material, especially for a body protection article - Google Patents

Abstract

This invention relates to a process for the treatment of insulating materials in the supple, fluffy state, such as down, wherein the fluff of the down is subjected to a physical treatment adapted to take the filaments of the fluff into a substantially radial position, giving the fluff its maximum volume in which it is stabilized by the superficial deposit of a resin. The apparatus for carrying out the process comprises a dehydration enclosure in the form of a rotating drum with inner blades, hot air inlet and upper evacuation. The invention is more particularly applicable to the treatment of down for filling duvets, sleeping bags or the like.

Description

The present invention relates to a process for the preparation and processing of filling materials in the divided state and of low density, of flaky structure and intended more especially for the production of flexible protective envelopes for body use.

The invention relates more particularly to the preparation, treatment and conditioning of materials such as down intended for the production of body thermal protection envelopes such as eiderdowns, quilts, anoraks, winter clothes, sleeping bags, etc. ...

The invention therefore essentially relates to the preparation and treatment of packing materials for protective articles with high insulating power or "adiathermic" power and using natural duvets taken essentially from aquatic animals.

We know that down is a spherical flake with a central core, from which flourish a multitude of filaments, themselves hairy, allowing it to trap an amount of air equal to its entire volume. A flake contains more than 1000 air tanks. It is a natural element, taken from the skin of aquatic animals, which it provides thermal protection for the body.

Very light, it has the highest insulation power currently available, it is used to make insulating items: clothing, quilts, comforters, sleeping bags, etc.

The down differs from the feather by its absence of rigid rod, by its lightness and its property of storing the air.

Unlike the down described above, the feather that makes up the outer plumage of birds has a primary shaft or axis, with its horny tube, which the stem surmounts accompanied by its beards planted laterally. The beards are broken down into barbules and barbels.

The poultry feather is very flat. It is sometimes used in the stuffing of poor quality cushions and pillows. It does not contain air.

The feather of aquatic animals (eider, goose or duck) is arched, it is used as a bedding filling: feather beds, pillows, bolsters, cushions (we lie on it). It does not contain air, but has excellent compressibility.

In the techniques currently used, down undergoes, after removal from dead or alive animals, various degreasing operations, washing, spinning, steaming and treatments using various products intended to ensure preservation and to give it a pleasant color. (optical brightener) after which it will be compressed to 10 for storage, transport on land and up to 50 for export by sea.

The manufacturers of down articles therefore use a raw material which has undergone deterioration due to excess compression, the downs becoming entangled in each other and the filaments separating from the flake, creating dusts which reduce the volume of immobilized air and cause respiratory discomfort and allergic reactions of users.

In addition, it has been observed that natural down is considerably affected by the cold (which makes it shrink) and the humidity (which softens its structure) so that in winter, when the atmosphere of workshops has a high humidity, it becomes necessary to greatly increase the filling weight of the articles to maintain the normal volume. Indeed, a new down contains 55% of water, a ball of down takes 15 to 20% of humidity on a single night and it is not rare to note hygrometric levels of matter on the order of 90% in winter.

It therefore appears from the foregoing observations that the filling power, during production, and the insulating power, during use, of the material constituted by the down, remains largely dependent on its sensitivity to humidity.

It is moreover an observation of current experience that a body insulation blanket (a sleeping bag, an anorak or any garment) has a much more effective and high insulating and thermal protection power when it is used. in the dry state.

It is precisely when the external conditions are at their maximum aggressiveness (wet cold) that the protective cover loses part of its effectiveness given its sensitivity to humidity.

It is therefore desirable to be able to benefit from body protection structures which, while benefiting from a high insulation coefficient, are largely shielded from the influence of humidity so as to present an effective barrier and defense against the cold. , also in wet conditions, more particularly aggressive, only in dry cold conditions.

The method according to the present invention aims precisely to improve and considerably increase the insulation power of the material used by dimensional increase in the volume of the unit flakes which are blocked in their increased dimensional structure while they are made very largely insensitive to outdoor humidity.

It is known (as mentioned above) to treat down before use, so as to give it various properties making it possible to improve its capacity for preservation and its resistance to aging agents such as parasites.

Provision has also been made, according to French patent No. 76 20 744, to incorporate products such as synthetic resins into the feather cleaning liquid; but this treatment which is carried out in the liquid phase (and which concerns feathers) is incapable of improving the volume of the unit elements and remains without effect on the humidity protection.

US Patent 2,715,086 also relates to the treatment of feathers which can receive a coating of wax, resin or elastomer to improve their filling power; but this treatment is provided for feathers precisely with a view to bringing their properties closer to those of down; and the treatment has no effect on the dimensional structure of the product.

On the contrary, the present invention makes it possible, by increasing the volume of each unit flake, to immobilize a greater quantity of air in the same weight of material and therefore to increase the efficiency of the product thus treated.

Another no less important object of the invention is to stabilize the down in the dimensional structure which has thus been conferred on it.

And this mechanical stability of the down is accompanied by an insensitivity of the material to the harmful influences of a humid atmosphere by giving the product the ability to resist the penetration of moisture into the volume of air trapped inside the structure of the flakes.

In addition, the treatment according to the invention will allow the maintenance of protective structures (duvets, sleeping bags, anoraks) under improved and simplified conditions allowing an increase in the life of the article.

Finally, the invention will make it possible to confer on lower quality duvets, for example second choice duvets or used duvets, renovated properties of thermal resistance by modification of their dimensional structures and their resistance to humidity.

• a) le matériau est soumis à une phase de déshydratation
• b) le matériau à l'état sensiblement anhydre est soumis à enrobage par une résine en solution dans un solvant, la solution étant projetée par pulvérisation
• c) le matériau est soumis à une phase d'évaporation du solvant et de polymérisation de la résine d'enrobage pour obtenir un film recouvrant la surface de chaque élément.

To this end, the invention relates firstly to a process for treating insulation materials in a flexible and flaky state such as down and intended for the lining of body protection structures, and the treatment is characterized by the succession of following operations:

• a) the material is subjected to a dehydration phase
• b) the material in the substantially anhydrous state is subjected to coating with a resin in solution in a solvent, the solution being sprayed
• c) the material is subjected to a phase of evaporation of the solvent and of polymerization of the coating resin to obtain a film covering the surface of each element.

Preferably, the dehydration phase is carried out by suspending the flakes of down in a stream of hot, dry air for the time necessary to ensure thorough dehydration.

Preferably, the coating resin is provided with properties of high surface tension with respect to water and the resin is chosen from the group comprising fluorinated resins and silicone-based resins.

More specifically, the coating coating is produced by spraying a mist of the resin solution in an appropriate solvent, under high pressure and in an enclosure containing the fluff of fluff in motion being suspended in a gaseous phase (such as air) dry, said gas phase being brought to a temperature corresponding to the polymerization of the resin.

Another object of the invention relates to the application of the above method to the renovation of used duvets.

The invention also relates to an apparatus for implementing the above process and characterized in that it consists of a dehydration chamber formed by a rotary drum provided with internal paddles and capable of containing the down fluff in suspension and kept in motion by the rotation of the drum, the drum having perforations on its wall and being inserted inside a capacity provided with an outlet at its top and a hot air inlet at its base, the central axis of said rotary drum being occupied by a tube provided with injection nozzles connected to a source of the pressurized solution constituted by the coating resin in its solvent.

The invention also relates to the filling material resulting from the implementation of the above process and characterized in that it consists of an insulation material in the flexible and flaky state such as the down used for the lining of flexible body thermal protection structures such as eiderdowns, quilts, sleeping bags, anoraks, each unit flake containing an air phase in the substantially anhydrous state and comprising a coating film in the solid state and formed a thin film of resin having a high solid / liquid surface tension, in particular with respect to water and ensuring the flakes a capacity for resistance to humidity from the external environment.

The invention also relates to insulating structures in flexible and deformable form for bodily insulation, of the type consisting of an outer covering and an inner filling in the form of down such as eiderdowns, sleeping bags, duvets or anoraks, characterized in that the unitary elements constituting the filling material conforms to the preceding characteristics and each flake of the filling material comprises a coating film formed from a thin film of resin having a high solid / liquid surface tension, in particular with respect to the water and able to give down a property of resistance to external ambient humidity.

Other characteristics and advantages of the invention will emerge from the description which follows and which is given in connection with a particular embodiment presented by way of example.

• FIG. 1 represents a schematic view of a unitary flake of fluff as used within the framework of the implementation of the present invention and seen before the treatment of the invention.
• FIG. 2 represents the same unit flake after treatment.
• FIG. 3 represents a schematic perspective view and partial cutaway of an apparatus for implementing the treatment according to the invention.

Figures 1 and 2 show the dimensional structure of the unit flake before treatment (Figure 1) and after treatment (Figure 2) respectively.

It can be seen that the heat treatment according to the invention, and the operating phases of which will be described below, has made it possible to modify the dimensional structure of the flake which has considerably expanded under the effect of heat.

The multiple filaments that make up the flake are in the initial state largely entangled and packed in on themselves, consequently reducing the total volume they occupy from the central nucleus; this corresponds to the natural state of the down during its live use on the body of the carrier animal, the down being then largely impregnated with the natural oils exuded by the body of the animal and being necessarily compressed by the upper layers plumage.

And this compressed state is then often aggravated by the stages of treatment of the down in liquid phase followed by its compression for the needs of transport.

The heat treatment which will be described below makes it possible to develop the filaments which assume a substantially radial general position from the central core by relaxing and then allowing the flakes of down to occupy a volume space corresponding substantially to a sphere whose radius would correspond to the average length of the filaments.

And we see that in this structural modification, which will be stabilized and crystallized by the subsequent treatment, allows the flakes to acquire an increased volume in a proportion between 30 and 50% compared to the initial volume.

It follows that the mass of air constituting the actively insulating material of the lining is increased in the same proportions.

So that the same amount of down (by weight) after the treatment of the invention, occupies a volume of 30 to 50% greater and consequently has an increased insulating power in the same proportions.

The operative treatment according to the invention begins with a dehydration phase.

Dehydration could be carried out by known chemical means, for example by exposing the down in an atmosphere of air in contact with a product. absorbing moisture such as quicklime, silica gel, calcium chloride etc ...

This relatively slow method will be preferred thermal dehydration which can be carried out in the same device used later in the next phase of stabilization by coating with a coating material.

According to Figure 1, the apparatus used in the context of the implementation of the invention comprises an enclosure 1 provided with an inlet 2 at its base and a discharge opening 3 at the top, and consisting of a box.

Inside this enclosure is mounted a rotary drum 4 whose side walls 5 are full or preferably made of glass plates, cooperating with the side glass walls of the enclosure 1 thereby allowing visibility inside of the cylinder to allow control of operations. Access openings are provided (but not shown in the drawing)

The peripheral walls 6,6 ′, 7,7 ′ of the drum consist of an openwork structure, for example a perforated sheet or a mesh (for example made of expanded metal).

So that the interior space of the drum is thus in communication with the gas phase prevailing within the enclosure 1.

Radial paddles 8,8 ', 9,9' are arranged towards the periphery of the drum to improve the mixing of the material.

At the base and through the inlet 2 is blown a stream of hot air gradually brought to 100 ° and coming from a blower or a heating source (not shown); the hot air is evacuated at the top 3 and it can advantageously be recycled after passing through means allowing the elimination of humidity and heating.

At the end of the operation, the average humidity level of the air trapped within each flake of the down was brought to a level of between 20 and 25% corresponding to the dimensional state of the down as shown in FIG. 2.

It is understood that the drum is rotated by conventional means around the hub 10; the slow rotation allows continuous mixing of the flakes of down introduced into the drum; the flakes fall slowly down where they are taken up by the pallets 8,8 'etc ... and lifted towards the upper part from where they escape by gravity to fall slowly down when meeting the air flow hot rising to which they regularly give up their humidity gradually.

In the subsequent phase corresponding to the water repellency treatment, the down remains in suspension in the drum, always driven in slow rotation (one to two revolutions per minute).

In this phase the upward current of hot air 2 has been stopped and the injection pipe 11 is used which occupies the central axis of the drum and which opens on the outside at 12 connected to a pressurized source, to inject inside the volume of the drum in the state of mist or mist the solution consisting of a coating resin in a solvent.

The internal axial tube 11 is provided for this purpose with ejection nozzles 13, 13 ′ which spread in the interior space of the drum a mist consisting of the resin in solution.

It is fed from the outer pipe 12 under high pressure _(8-1 0 kilograms per cm ^2).

During this period the down in suspension and entrained in the vortices linked to the slow movement of the drum permeates regularly and, on the surface of the solution particles, at the level of the individual filaments of the down.

Preferably, quick-evaporating solvents are chosen, the solvents being discharged through the upper outlet 3.

Preferably, water-repellent resins chosen from the group comprising fluorinated resins and silicone resins will be used.

The proportion of resins per 20 kilos of down will be of the order of 40 to 50 grams in a liter of solvent.

At the end of treatment when substantially all the solvent is removed, the resin being deposited and constituting a surface film along the filaments constituting each flake, the treatment ends in the polymerization phase during which air brought to 130 °. is blown into the enclosure containing the drum, while continuing the slow movement of rotation and agitation of the mixture.

A perfectly homogeneous whole is thus obtained in which all the unit flakes have substantially the same structure and the same coating.

At the temperature of 130 ° the resin polymerizes, the chemical bonds which are established to obtain the chains with high molecular weight conferring on the resin film its final mechanical structure allows crystallize the flake in the expanded state which the previous phase of dehydration and thermal elevation will have led to.

At the end of the operation, the assembly is allowed to cool to obtain an expanded down, developed and stabilized in this inflated dimensional structure, the humidity level of which is reduced to a rate of 25% maximum.

And this rate will then be maintained whatever the conditions of use and the ambient environment in which the article and the down filling it contains, will be placed.

Indeed, the presence of the water-repellent resin film on the filaments, thanks to the high surface tension of the resin film relative to the water vapor, allows the down to repel the air charged with ambient humidity, the air dry content in the interstitial spaces between the filaments of each flake remaining in place without hygrometric exchange.

The product having undergone the treatment is then immediately used for the filling of finished products and articles of use such as quilts, sleeping bags, anoraks, etc.

The down thus used and which has undergone the treatment described above has an increase in volume varying from 30 to 40% depending on the qualities; this means that to obtain the same insulation it is possible to use a quantity of material 30 to 50% lower; which represents a saving of up to 50% in the price of the raw material.

Under these conditions, the implementation of the method according to the invention makes it possible to obtain, in the manufacture of body protection articles filled with down, extremely competitive cost prices combined with exceptional profitability.

Experiments have shown that the down filling which has undergone the treatment according to the invention retains its volume even if it is stored in a humid environment; to this end, tests were carried out for several months in an environment containing more than 90% humidity.

The article filled with down according to the invention escapes the constraints of the cold which would risk reducing its volume and its insulating power, just as it escapes the constraints of humidity greatly reducing its insulating power and which would also entail risks of mold.

The article produced according to the invention no longer needs to be ventilated every day (to evacuate the moisture stored in body contact) since the article resists the absorption of moisture.

It is therefore sufficient to ventilate it only once a week and then it can even be ventilated even in a humid environment, for example in foggy weather.

The article can be exposed to the sun because the filaments thanks to the coating resin film are largely protected from radiation in the ultraviolet.

The packing product, thanks to the treatment of the invention, is made unassailable by vermin and parasites.

The process of the invention by stabilizing the down in its structure avoids the formation of elements detaching from the filaments and which constitute dust; this prevents respiratory discomfort in sensitized subjects and users.

In the case of use of the down according to the invention for the production of articles and bedding fittings, the development of parasitic mites living in the bedding and feeding on down debris is avoided.

It is known that the presence of these parasites is often a source of allergic reaction in certain subjects, under these conditions the use of a protective cover using the lining according to the invention will allow the elimination of this drawback.

The service life of the article comprising the lining according to the invention is greatly increased due to the contributions made by the treatment; greater mechanical resistance to compression and cancellation of the stresses linked to humidity, parasites and devitalization are obtained, in particular under the effect of solar radiation.

The article according to the invention also represents properties of perfect resistance to repeated dry cleaning or to water cleaning.

The method according to the invention advantageously allows not only the considerable improvement in the properties and qualities of new down, but it also allows the recovery and renovation of so-called "down duvets".

Coated down which is 4 to 5 times cheaper than new down can, thanks to the process of the invention, find the same properties and the same qualities as new down, which allows the recovery of old down and a considerable saving of raw material. 1

Tests and controls carried out by the applicant made it possible to compare the adiathermic power of the down treated in accordance with the invention compared to a conventional down.

The tests were carried out according to standard NF G 07 107.

The adiathermic power on a reference duvet filled with conventional down at the rate of 600 grams per square meter was established at PA = 88.2%

• - 200 grammes au mètre carré PA = 81,6
• - 250 grammes au mètre carré PA = 85,4
• - 300 grammes au mètre carré PA = 87,3

The same tests revealed that a duvet filled with down having undergone the treatment according to the invention had the following coefficients as a function of the filling rates:

• - 200 grams per square meter PA = 81.6
• - 250 grams per square meter PA = 85.4
• - 300 grams per square meter PA = 87.3

It can be seen that, in order to obtain the same adiathermal power, an amount of half the quantity compared to the amount required using conventional down is used in the case of a duvet filled with down according to the invention.

It is clear that the process of the invention can be used for pure down, such as down containing a variable proportion of downy feathers.

The process of the invention, which has been described above and illustrated in FIG. 3 by unit loads, can also be carried out continuously.

The cylinder 4 can then be produced in great length and along a slightly inclined axis; the down introduced at the highest part would be discharged at the lowest part after passing slowly through the cylinder passing in a first phase corresponding to a dehydration phase in which it is subjected to a current of hot air, then to a phase of coating with the fog of the resin solution followed by the final phase of polymerization by thermal elevation with final cooling.

Claims (9)

1.- Method for treating insulation materials in a flexible and fluffy state such as down and intended for the lining of body protection structures, and the method is
characterized in that the flakes of the down are subjected to a physical dehydration treatment capable of bringing the filaments of the flake into a substantially radial position by giving the flake its maximum volume. 2.- Method according to claim 1,
characterized in that the physical dehydration treatment comprises suspending the flakes of down in a dry gas atmosphere at a temperature of the order of 100 ° C. 3.- Method according to one of claims 1 or 2, characterized by the succession of the following operations: a) the material is subjected to an expansion and dehydration phase by suspension in a stream of a hot gas such as hot air; b) the material in the substantially anhydrous state is subjected to coating with a resin in solution in a solvent, the solution being sprayed. c) the material is subjected to a phase of evaporation of the solvent and of polymerization of the coating resin to obtain a film covering the surface of each element. ₄ - Process according to claim ₃ ,
characterized in that the coating resin is provided with high surface tension properties with respect to water and the resin is chosen from the group comprising fluorinated resins and silicone-based resins. ₅ - Method according to one of claims 3 or 4,
characterized in that the coating coating is produced by spraying a mist of the resin solution in a suitable solvent, under high pressure greater than 3 K / cm ² and in an enclosure containing the fluff of fluff in motion being suspended in a dry gas phase (such as air), said gas phase being brought to a temperature at least equal to the polymerization temperature of the resin. 6 - Apparatus for implementing the method according to one of claims 1 to 5,
characterized in that it consists of a dewatering chamber formed by a rotary drum (4) provided with internal pallets (9,9 ') and able to contain the down in suspension and kept in motion by the rotation of the drum , the drum having perforations on its wall and being inserted inside a container (1) provided with an outlet (3) at its top and an inlet (2) for hot air at its base, the central axis of said rotary drum being occupied by a tube (11) provided with injection nozzles (13,13 ') connected to a source of the pressurized solution constituted by the coating resin in its solvent. 7 - Product obtained by implementing the method according to one of claims 1 to 5,
characterized in that it consists of an insulating material in the flexible and flaky state such as down for the lining of flexible structures for body thermal protection such as eiderdowns, duvets, sleeping bags, anoraks, each unit flake being in its substantially maximum expansion state, the filaments being in a substantially radial position and trapping between them an air phase in the substantially anhydrous state and the filaments comprising a coating film in the solid state and formed of a thin film of resin having a high solid / liquid surface tension, in particular with respect to water and ensuring the flakes a capacity for resistance to humidity of the external medium. 8 - Filling material according to claim ₇ , characterized in that the coating resin is chosen from the group comprising fluorinated resins and silicone resins. 9 - Insulating structures in flexible and deformable form for body insulation, of the type consisting of an outer envelope and an inner filling in the form of down such as comforters, sleeping bags, duvets or anoraks,
characterized in that the unitary elements constituting the filling material conform to claim or claim ₈ .

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