EP0075499A1 - Absorbent composite, especially for the manufacture of socks for footwear - Google Patents

Abstract

The problem posed consists in reducing as far as possible the physical drawbacks and psychological effects associated with excessive perspiration without, however, preventing this natural perspiration. According to the invention, this result is achieved in that the absorbent composite used as sock consists of a combination of two superposed materials, the first being formed partly from defibrated leather fibres and partly from synthetic fibres, these various fibres being bonded together by the addition of a resinous binder, the second being formed of an absorbent felt with a high retention capacity, the two materials being assembled over their entire surface by means of spots of adhesive (3) and peripheral sewing (4). The invention is applicable to all winter or summer footwear. <IMAGE>

Description

The invention relates to an absorbent complex specially adapted, but not exclusively, for the production of cleansing insoles for footwear.

Role of perspiration: it has two important functions which are the regulation of the external temperature of the body on the one hand, and the elimination of dermal toxins on the other hand.

Thus, sweat lowers the temperature of the bodily areas where it is emitted, and in addition, evacuates various materials among which urea, creatinine, uric acid ... etc.

Stimulation of perspiration: sweat is emitted by the sweat glands which are very numerous at the level of the foot (375 glands / cm2).

• - augmentation de la température des tissus,
• - augmentation de la compression des tissus,
• - action du système nerveux autonome sympathique (anxiété, peur).

The excitation of these glands is still a relatively ill-defined phenomenon, however the stimulating factors are of three types:

• - increased tissue temperature,
• - increased tissue compression,
• - action of the sympathetic autonomic nervous system (anxiety, fear).

The quantitative aspect: the amount of sweat emitted is very variable depending on the subjects, the temperature and the region of the body.

For the whole body, the average daily value for an individual weighing sixty-five kgs and subjected to a temperature of 25 ° C is between 1.5 liters and 2.5 liters. However, extreme values of pathological character have been observed, ranging from a minimum of 0.10 liters to a maximum of 10 liters.

Regarding the foot, the average emission is around 15 to 20 cm ³ per day, but there are huge differences from one individual to another.

• Malgré ses rôles régulateurs importants et naturels, la transpiration provoque l'inconfort d'une grande partie des individus.

Some disadvantages of sweating are given below:

• Despite its important and natural regulatory roles, sweating causes discomfort for a large part of individuals.

In fact, a third of this population suffers from the permanent drawbacks of excessive sweating and another third is subject to these inconveniences in summer or during intense physical efforts.

On the other hand, the regular increase in the use of sports shoes increases each year the percentage of people experiencing these disadvantages, because they are generally designed without taking into account hygienic problems.

• - un excès d'humidité,
• - l'apparition de mauvaises odeurs.

. The disadvantages of sweating are essentially of two types:

• - excess humidity,
• - the appearance of bad smells.

Foot moisture: as everyone knows, sweat is made up of 99% water. This humidity, not only unpleasant to wear, also causes dermatoses (Atlétic Foot).

Bad foot odors: sweat, odorless on emission, quickly becomes smelly. This condition called BROMHIDROSE comes from the decomposition of organic matter, certain bacteria finding there a favorable environment for their development play an important role in this decomposition.

The lack of personal hygiene and the lack of ventilation in the shoes are factors that accentuate this process.

Some means are known for reducing the drawbacks of perspiration at the level of the foot.

First of all, there are chemicals that have an astreingent action, that is to say that reduces perspiration by tightening the pores of the skin. This anti-perspiration solution modifies a natural phenomenon which fulfills positive functions for the body and is therefore to be avoided for obvious reasons medically.

Leather is rightly regarded as the suitable material to avoid excessive humidity. Indeed, leather absorbs water well but does so slowly and has no deodorant action.

In addition, there are many deodorant products either in an atomizer or incorporated into an insole (activated carbon), but these products are very effective in time and do not solve the problem of humidity.

To date, therefore, there are no products on the “market” with complete and lasting efficacy to eliminate the drawbacks of perspiration at the feet.

The invention therefore aims at a new means making it possible to reduce, as far as possible, the physical inconveniences and the psychological consequences linked to excessive sweating, without however opposing this natural sweating.

This means is the result of the new combination of two known means, hitherto used separately, but never combined in the form of the same complex to obtain. unexpected benefits.

Non-woven materials obtained by the dry route are in fact made up partly of short natural fibers, such as defibrillated leather fibers, and partly of synthetic fibers, these natural and synthetic fibers being consolidated and joined together by the addition of a resinous binder, the material thus formed then undergoing a sewing-knitting operation.

Other materials of the highly absorbent type are known, for example felts with great retention power, consisting mainly of cotton associated with a binder to synthetic fibers, for example polytetrafluoroethylene fibers.

It has been observed that the nonwoven material, by virtue of its permeable, ventilated structure, and above all because of its composition and its isotropic type texture, exhibits a great power of diffusion, that is to say that moisture absorbed locally is immediately distributed over the entire surface.

It has also been observed that if this diffusing material is combined with a felt having a high retention power, one then obtains a real moisture trap combined with a reservoir by pumping effect.

The invention therefore relates to an absorbent complex, in particular for the production of cleanliness insoles for footwear, characterized in that it consists of a compound of two superimposed materials, the one on top of which acts as a moisture diffuser and that of below the role of moisture reservoir or vice versa, the first material being formed partly of defibrillated leather fibers and partly of synthetic fibers, these various fibers being linked together by the addition of a resinous binder, and the second material being, meanwhile, formed of an absorbent felt with great retention power, the two materials being assembled over their entire surface by a point bonding and a peripheral seam.

According to one characteristic of the complex, the diffusing material consists of a nonwoven product obtained by the dry route and formed of 49% of defibrillated leather fibers and 50% of polyester fibers and of 1% of polyethylene.

According to another characteristic of the complex, the reservoir material consists of an absorbent felt comprising 75% of cotton fibers, 23% of polytetrafluoroethylene fibers and 2% of binder.

• - la Fig. l est une vue en plan d'une première de prupreté réalisée à partir du complexe selon l'invention ;
• - la Fig. 2 est une vue en coupe longitudinale de la Fig. 1.

A complex according to the invention is shown by way of nonlimiting example in the appended figures in which:

• - Fig. l is a plan view of a first prupreté made from the complex according to the invention;
• - Fig. 2 is a view in longitudinal section of FIG. 1.

According to the invention, the original complex, which makes it possible for the first time to provide a natural, universal and long-lasting solution to perspiration of the foot, consists of two strictly complementary materials, assembled together in the form of a binary type complex, the top material preferably being a nonwoven obtained by the dry process and acting as a diffuser, while the bottom material is formed from a nonwoven mattress acting as a moisture reservoir or vice versa.

The upper material 1 which has the purpose of trapping moisture and diffusing it instantaneously over the entire surface of the sole (Fig. 1) consists, in known manner, of a mixture of short natural fibers and synthetic fibers consolidated and associated by a resinous binder, the natural fibers possibly being fibers of defibrillated leather, and the synthetic fibers of polyester fibers, the material thus composed then undergoing a sewing-knitting operation. This type of material is generally made up of synthetic fibers and natural fibers in substantially equal proportions, for example 50% for the former and 49% for the latter, plus 1% of binder.

These materials have a permeable and airy fibrous structure, absorbing and diffusing moisture.

This first material is combined with the reservoir mattress 2 which is cut to the same contour as the first material, the two components being bonded to each other from time to time over the entire surface of the sole by bonding points 3 (Fig. 2) supplemented by a seam. zigzag device 4.

The reservoir material is made up of an absorbent felt formed mainly of cotton fibers and, to a lesser extent, polytetrafluoroethylene fibers, the whole being assembled by a binder.

This nonwoven with great retention power is perfectly known in particular for the manufacture of diapers for children or for feminine hygiene articles. One can, for example, use a felt comprising 75% cotton fibers, 23% polytetrafluoroethylene fibers and 2% binder, this material being designed in such a way that the water which it retains does not come out under pressure of the foot, thus avoiding the sponge effect.

According to another important characteristic of the invention, the first of cleanliness obtained by the superposition of the two aforementioned materials, is impregnated in depth with a special deodorant whose action spreads over time for about three months, due to the retention of the diffuser material 1 and of the reservoir that constitutes the felt 2.

The invention therefore provides a solution to the drawbacks of humidity and odor and the measurements carried out by the Technical Center for Leather show that the invention has an absorption capacity greater than that of a croupon leather first known for this quality.

The results are collated in the table below.

The dynamic water absorption capacities were measured with the comfort perméometer which represents the reality of wearing, the maximum capacities were measured by immersion in water.

The values were reported at the same thickness of 2 mm.

If these values are brought to the surface of a size sole 41, it can be seen that the invention can retain 33 cm3 of water, which largely covers the average daily sweat emission from the foot, which is between 15 and 20 cm3.

For clarity, the quantities of water retained by the tested articles have been reported to one square meter:

The invention also provides a solution to bad odors, due to the presence of a long-effective deodorant. This deodorant is neither a bactericide nor an antiperspirant, its action is obtained by an odor absorber.

It has been specially developed to be deposited on the first cleanliness and to be retained there, which increases its lifespan.

When the original impregnation loses its effectiveness, the user recharges the support by simple projection, and the deodorant action starts again for three months. The spray bottle containing a volume of four impregnations, the user therefore has at his disposal a system with an efficiency greater than one year.

The first cleanliness according to the invention has long-lasting absorption qualities. Indeed, the absorption capacity of the sole according to the invention is such that it largely covers the daily emission of sweat, but in addition this first dries overnight and can therefore again play its role the next day.

This drying time can be shortened by removing the first one from the shoe in the evening.

On the other hand, the wearing tests show that the first according to the invention is solid and does not degrade on friction, its lifespan is therefore great.

Finally, this first cleanliness can be machine washed without more care than a synthetic fabric, avoiding exceeding the temperature of 50 ° C. Indeed, up to this temperature, the leather fibers contained in the sole retain their mechanical properties.

Finally, the low volume of the first according to the intake allows it to adapt to all shoes without reducing the footwear volume.

On the other hand, the shape of the first has been studied to correspond to all the varieties of the first assembly.

Claims (2)

1. Multilayer absorbent complex, in particular for the manufacture of first socks for footwear, the various layers of which are possibly joined around their periphery by a seam, characterized in that it consists of a compound of two superimposed materials including that from above (1) acts as a humidity diffuser and from below (2), the role of moisture reservoir, the first material being formed partly of defibrillated leather fibers and partly of synthetic fibers, these different fibers being linked together by the addition of a resinous binder, and the second material being, meanwhile, formed of an absorbent felt with great retention power, the two materials being assembled over their entire surface by bonding point (3) and a peripheral seam (4). 2. Complex according to claim 1, characterized in that it is soaked with a deodorant with long life, this deodorant being trapped by the diffusing material (1) and trapped in the reservoir material (2).

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