EP0201779B1 - Method for crimping artificial hairs made of synthetic monofilaments in order to make false hair - Google Patents

Abstract

To crimp artificial hair made of synthetic monofilament fibres in order to make hairpieces, the artificial hair is, at 118 DEG C or higher, a) crimped with water vapour-saturated hot air or b) admixed with a moisture-holding agent and crimped with hot air at from 150 DEG to 180 DEG and c) crimped in an autoclave in the region between wet steam and saturated steam. The advantage achieved here is that reshaping of the hair is possible without embrittlement and that good colourability and also colour fastness in relation to light and washing are obtained. <IMAGE>

Description

The invention relates to a method for crimping synthetic hair from synthetic monofilament fibers in a warm, humid atmosphere for the production of hair replacement parts, in which the synthetic hair is treated at a temperature above its plastic deformation point.

• 1. Sie müssen natürlichem Haar ähnlich, oder besser gleich sein.
• 2. Sie sollten formstabil sein, um den verschiedenen Anforderungen beim Tragen auch unter extremen Bedingungen, z.B. Sauna gerecht zu werden.
• 3. Sie müsen im Griff natürlichem Haar ähnlich sein oder angepaßt werden.
• 4. Sie müssen modelliert werden können, also entsprechend den Wünschen der Träger von Haarteilen gekräuselt und gewellt werden können.

The use of so-called monofilament synthetic fibers for har replacement depends on the following factors:

• 1. They have to be similar to natural hair, or better be the same
• 2. They should be dimensionally stable in order to meet the various requirements when worn, even under extreme conditions, such as saunas.
• 3. They have to be similar to natural hair or have to be adjusted.
• 4. They must be able to be modeled, that is, they can be curled and waved according to the wishes of the wearer of hair pieces.

Patent application no. DE-A-34 31 886.0-26 dated September 17, 1985 has recorded a way in which thermally resistant monofilament synthetic fibers can be adapted to natural hair in terms of its external appearance, that is to say in its glossy appearance. This hair replacement material treated in this way can only be insufficiently processed into hairstyles with the previously used crimping methods.

Hot air treatments with the well-known hair dryer resulted in excessively long production times, and the handle of the material became hard and brittle. Treatment in boiling water does not sufficiently stabilize the shape of the waves and frills.

In particular, polyester monofilament hair must be broken down very strongly before dyeing in order to get a hair-like appearance. This is achieved by appropriately breaking down more than 30% of the fiber substance, preferably by hydrolysis. Such a strong change in the fiber suggests that the shape of the fiber is also significantly impaired in its long-term stability. British Patent 664921 also points out that strong fiber degradation also leads to high strength losses. It had to be assumed that the mechanical influences, such as those present when washing and combing synthetic hair, are only possible through a subsequent heat setting which is optimal for polyester fiber at temperatures of 185 ° C. and more, and under at least slight tension after the surface treatment , permanently survives. To date, technology has assumed that permanent deformation on polyester fibers can only be achieved with hot air temperatures above 185 ° C. You would have to expect that from a polyester monofilament fiber that has been broken down by more than 30%.

The state of the art also applies that when heat setting with hot air, polyester filament becomes brittle with increasing temperature and the sublimation of the dyes increases with increasing temperature, so that the coloring suffers.

• a) die Waschechtheit verringert wird,
• b) die Auswahl der Farbstoffe in einem Maße begrenzt wird, daß die Anforderungen an Kunsthaarersatzteilen in Bezug auf farbgetreue Naturhaar-Nuancen praktisch unmöglich wird, und auch durch die Farbstoffbeschränkung die erforderliche Lichtechtheit nicht immer zu erreichen ist,

war der Weg über waschbeständige Heißluftverformung von Kunsthaar aus gefärbtem Polyester-Monofil-Material als aussichtslos anzusehen.Since only a few dyes have grown temperatures above 180 ° C without sublimating, which means

• a) the fastness to washing is reduced,
• b) the selection of the dyes is limited to such an extent that the requirements for synthetic hair replacement parts with regard to color-true natural hair nuances become practically impossible, and the required lightfastness cannot always be achieved due to the dye limitation,

was the way through wash-resistant hot air shaping of synthetic hair made of colored polyester monofil material as hopeless.

According to GB-A-1 374 170, polyacrylic fibers are crimped in a warm, moist atmosphere at temperatures of 55 to 80 ° C., temperatures outside this range being considered unsuitable. It is also recommended to use a humidity atmosphere of less than 100%. In contrast to this, according to the invention, the synthetic hair consisting of monofilament fibers is crimped at the specified higher temperatures in a pressurized steam atmosphere. Steam conditioning of polyamide threads is also known from US Pat. No. 3,595,952 in order to improve their knot strength. The polyamide thread is drawn through a saturated water vapor atmosphere within a very short period of 10 milliseconds to 5 seconds. The goal of a smooth, knot-resistant thread is in contrast to the permanent crimping of monofilament fibers aimed at according to the invention.

The invention has for its object to curl monofilament fibers for a long time without embrittlement and disadvantageous sublimation of the dyes used for dyeing.

• a) bei Temperaturen ab 118°C mit wasserdampfgesättigter Heißluft eingekräuselt wird oder
• b) mit einem feuchtigkeitshaltenden Mittel versetzt und mit Heißluft von 130°C bis 180°C eingekräuselt wird
  oder
• c) bei Temperaturen ab 118°C im Autoklaven mit Dampf im Bereich zwischen Naßdampf und Sattdampf eingekräuselt wird.

This object is achieved in that the synthetic hair

• a) is crimped at temperatures above 118 ° C with steam-saturated hot air or
• b) mixed with a moisture-retaining agent and crimped with hot air from 130 ° C to 180 ° C.
  or
• c) is crimped at temperatures from 118 ° C in an autoclave with steam in the area between wet steam and saturated steam.

Extensive tests have shown that the handle of the synthetic hair material in question is supple and largely adapted to natural hair when the amount of liquid corresponding to its degree of water vapor saturation is added to the hot air, thereby avoiding over-drying. The use of a saturated pressure vapor atmosphere is particularly advantageous.

The reasons for this saturated steam crimping of the synthetic monofilament fibers used for synthetic hair, in particular polyester monofilament synthetic hair, are that a) the handle of the material is softer in the presence of a saturated pressurized steam atmosphere and b) the colored material is not thermally Sublimation in the fastness to washing is deteriorated because saturated steam of the required temperature of 132.8 ° C (2 atm) is sufficient for polyester. Wash-resistant crimps can be produced which, while maintaining the required natural hair-like shine, also give the desired soft feel to the synthetic hair material made of thermally resistant synthetic fibers.

A particularly preferred design is that synthetic hair made of synthetic monofilament fibers, in particular polyester monofilament fibers, is mixed with a moisture-retaining agent at temperatures of 130 ° to 180 ° C. and crimped with hot air.

In particular, it was found that synthetic hair made of polyester monofilament can be crimped in shape-stable at temperatures below 180 ° C. If you treat z. B. a polyester monofilament thread previously z. b. 40% has been degraded by hydrolysis, a washable and comb-resistant crimping with hot air of 170 ° C can be achieved. I.e. the curls, or curly hairstyles, which are made from it, can be washed and combed up to 100 times, without any noteworthy changes, even if they are worn in the sauna and under the prevailing atmospheric conditions.

It was found that by means of previously applied hygroscopic on the hair replacement material in question Connections with crimping below 180 ° C can also keep the handle of the material sufficiently soft and supple. Moisture of less than 4% of the weight of the material is sufficient to ensure a correspondingly good, smooth grip of the polyester monofilament material to be crimped in for hair replacement.

Monofilament fibers made of polyamide, polyurethane, polypropylene and especially polyester are preferred as synthetic hair.

By curling synthetic hair in a saturated steam atmosphere of one to four atmospheres at a temperature of approximately 118 ° C to 148 ° C, a soft handle of the hair is obtained, which is very hair-like, and a permanent wave. The hair reshaped in this way no longer deforms at the much lower shower and sauna temperature.

In particular in the case of treatment in an autoclave, it is preferably possible to add caustic alkali to the wet to saturated steam in accordance with the technical teaching of patent application DE-A-34 31 886.0-26 in order to give the fiber treated in this way certain light properties. It is also possible to add caustic alkali in the steam-saturated hot air treatment.

In addition to the addition of the above-mentioned chemical, it is also preferred if other chemicals are added simultaneously or successively, such as. B. perm chemicals and / or plasticizers and / or film-forming silicones.

Furthermore, it is preferred if, before the treatment of the synthetic hair with steam-saturated hot air or with wet to saturated steam, the synthetic hair is treated with chemicals which act on the synthetic hair during the subsequent steam treatment.

In a further embodiment, it is provided that before the synthetic hair is treated with steam-saturated hot air or with wet to saturated steam, the synthetic hair is first shaped with hot air without the addition of steam, in order to then be permanently fixed with the subsequent steam treatment.

It should be emphasized that the steam treatment of the hair can take place in all possible pressure and temperature ranges; the only important thing is that a pressure vapor atmosphere is created according to the material of the hair to be reshaped, which ensures permanent reshaping.

The use of water vapor prevents embrittlement of the hair fiber to be thermally treated, from which it becomes clear that both treatment with saturated steam (dry saturated steam) and treatment with wet steam can be considered. In the latter case, the saturated steam still carries parts of boiling liquid with it, which leads to a dampening effect when it hits the synthetic fiber.

A treatment with superheated steam (superheated steam) is also possible, but due to the low moisture content of the steam, the fiber becomes brittle as the temperature increases.

With regard to the state diagram for vapors, there is another area of application. Such a state diagram for vapors is characterized by the limit curves and the constant steam content curves in the wet steam area. All boiling points are on the boiling line and all saturated steam points are on the upper dew line. The two limit curves merge into one another at the critical point. The boiling line separates the liquid area from the wet steam area, the dew line separates the wet steam area from the hot steam area. In the area between the boiling line and the dew line, all steam states are the preferred treatment agents for the hair fiber to be converted here.

The invention is explained in more detail below with the aid of drawings which illustrate only one embodiment. Further features and advantages of the invention which are essential to the invention emerge from the drawings and their description.

Figur 1:

schematisiert die Behandlung des Kunsthaares in einem Autoklaven;

Figur 2:

schematisiert die Behandlung des Kunsthaares mit wasserdampfgesättigter Heißluft.

Show it:

Figure 1:

schematizes the treatment of synthetic hair in an autoclave;

Figure 2:

schematizes the treatment of synthetic hair with steam-saturated hot air.

In Figure 1, the autoclave for treating the synthetic hair 15 consists of a boiler 2, at the lower part of which a steam feed line 7 opens, which is supplied with steam by a steam generator 1, not shown. The steam feed line 7 opens into a pipe 19 arranged in the boiler 2 and provided with radial bores, on which the synthetic hair 15 is applied in the form of a coil. The steam flowing through the bores 14 radially passes through the synthetic hair 15 in the direction of the arrow 13 and at the same time also treats the synthetic hair 15 from the outside.

In a conventional manner, the boiler 2 is connected to a cover 3 by means of a screw connection 4 and a water inflow 5 also opens into the boiler and a water outlet 6 starts at the bottom. On the boiler wall a vent 8 as well as a thermometer 11 and a manometer 12 are also arranged.

The lid is provided with a steam tap 9 and a safety valve 10.

FIG. 2 shows, as a possible exemplary embodiment, the treatment of the synthetic hair 15 applied as a wrap on the tube 19 with a steam-saturated hot air stream. In a manner not shown, a blower 16 generates a hot air stream, to which a steam stream 17 is mixed by a steam generator.

To maintain the steam atmosphere, it is preferred in this case if the synthetic hair 15 and the tube 19 are surrounded on the outside by an air and water vapor permeable sheathing 18, so that the steam generated in this way only flows slowly into the environment. The synthetic hair 15 can also be moistened beforehand with water or a water-chemical mixture.

In the manner described above, the chemicals described above can be added to the steam generator 1, 17 in order to achieve an additional chemical treatment of the synthetic hair 15 in addition to the steam treatment. In addition to permanent corrugation, this also results in surface finishing and possibly also coloring.

The exemplary embodiments described above make it clear that steam treatment of the hair is possible both in an open and in a closed atmosphere.

While special apparatuses are required for the embodiment of the method described above using a) steam-saturated hot air or c) steam in the area between wet steam and saturated steam, such systems are used in the implementation of the method according to embodiment b) using a moisture-retaining agent and Avoid hot air.

In particular, a synthetic hair is used which has been mechanically or chemically degraded by at least 30% by weight.

The use of moisture-retaining agents on the hair material makes it possible to carry out the crimping with hot air at temperatures lower than 180 ° C.

• a) Paraffin-Kohlenwasserstoffe
• b) Fettsäure-Polyglykolester
• c) Phosphorsäureester, z.B. Mono- oder Diester auf Kokosfettbasis
• d) Fettsäure-Polyglykoläther
• e) Aminosäurederivate

For example, the following materials can be used on the monofil material as moisture-retaining agents after hydrolytic degradation:

• a) Paraffin hydrocarbons
• b) fatty acid polyglycol esters
• c) phosphoric acid esters, for example mono- or diesters based on coconut fat
• d) fatty acid polyglycol ether
• e) amino acid derivatives

The moisture-retaining preparations can be designed both as a dispersion and as an emulsion, these agents binding 0.1 to 4% of water, based on the fiber weight.

It is important for the handle that a certain residual moisture remains on the curling material, especially in the range of 0.1 to 4% by weight.

It is essential that a sufficient moisture content of the synthetic fiber is maintained during the forming.

The shaping takes place at hot air temperatures from 130 ° C., preferably at 150 ° to 180 ° C., in particular 150 ° to 160 ° C.

The use of moisture-retaining agents which bind enough water even at hot air temperatures of up to 180 ° C to sufficiently prevent embrittlement of the polyester monofil material significantly expands the range of dyes which can be used without the risk of sublimation. since the temperature does not have to be raised above 180 ° C.

For example, the dyes listed below can be used to dye the synthetic hair fibers, the dyeing not being damaged during the subsequent crimping treatment using moisturizing agents and hot air at up to 180 ° C.

This means that the dyes mentioned sublimate so little at temperatures below 180 ° C that sufficient fastness to washing is ensured for hair parts. In terms of light fastness, color uniformity with different light sources, such as. B. daylight, standard light, evening light, the dyes mentioned are particularly well suited especially in combinations for dyeing hair pieces made of polyester monofilament material. This has resulted in extensive dyeing tests and tests. If one were to treat the same dyes with hot air above 180 ° C, there would be considerable color shifts and, with strong colors, considerable bleeding during subsequent washing, which would make the use of the material for hairpieces impossible.

For example, the synthetic fiber starting material is degraded by alkalization with caustic alkali lye by 30 to 40% by weight, so that the fiber is roughened, then washed, neutralized, rinsed, dried and dyed. The dyeing is preferably carried out at 130 ° to 135 ° C under positive pressure. The synthetic hair coming from the dye bath is rinsed and treated with a moisture-retaining agent in dispersion or emulsion. A means is preferred that can be applied by rinsing in the bath, spraying or other application methods. The fiber treated in this way is dried so that a residual moisture content of preferably 0.1 to 4% by weight of water remains on the fiber. Then the crimping takes place by means of heat conversion by means of hot air at temperatures up to 180 ° C.

The treatment with hot air takes place in the range of about 10 to 60 minutes. The hair is then cooled in the sheath.

It is important and advantageous that the hot air treatment can be carried out at relatively low temperatures because the hair has previously been chemically roughened by the alkali treatment and is therefore particularly easily accessible for shaping, and the embrittlement of the hair is avoided by the use of the humectant.

The finished curled hair can be treated further, e.g. B. by applying plasticizers and / or heat protection agents, for. B. aluminum salts.

The advantages of the invention are, therefore, that crimping of the synthetic hair is possible without embrittlement and that excellent dyeability and color stability are achieved, since the degraded, in particular alkalized, fiber absorbs and maintains the dyes very well and low forming temperatures are used.

Another embodiment of the present invention provides for the use of carriers. The use of these carriers has the advantage that the polyester material can be colored and formed even at low temperatures, namely at cooking temperatures. Examples of such carriers are orthophenylphenol, oxycarboxylic acid methyl ester, chlorobenzene compounds and other compounds which are known as so-called carriers.

Claims (14)

1. A method for curling artificial hair (15) of synthetic monofilar fibres in a moist warm atmosphere for the production of hair replacements, characterised in that the artificial hair (15)

   a) is curled at temperatures from 118° C with hot air which is saturated with water vapour, or

   b) is mixed with a moisture-containing agent (21) and is curled with hot air of 130° C - 180°C, or

   c) is curled at temperatures from 118°C in the autoclave with steam in the range between wet steam and saturated steam.
2. A method according to Claim 1, characterised in that monofilar fibres of polyamide, polyurethane, polypropylene or in particular polyester are used as artificial hair (15).
3. A method according to Claim 1 or 2, characterised in that the artifical hair (15) is arranged in a covering (18) permeable to air and water vapour.
4. A method according to Claim 1 to 3, characterised in that potassium hydroxide is added to the hot air, which is saturated with water vapour, or to the wet steam.
5. A method according to Claim 1 to 4, characterised in that permanent wave chemicals and/or softeners and/or antistatic agents are added to the hot air, to the hot air saturated with water vapour or to the wet steam.
6. A method according to Claim 1 to 5, characterised in that before the treatment of the artificial hair (15) with hot air saturated with water vapour or with saturated-to-wet steam, the artificial hair is treated with chemicals which act on the artificial hair during the subsequent steam treatment.
7. A method according to Claim 1 to 6, characterised in that before the treatment of the artificial hair (15) with hot air, saturated with water vapour, or with wet steam, the artificial hair is firstly shaped with hot air without the addition of water vapour.
8. A method according to one of Claims 1 to 7, characterised in that the artificial hair (15) before the treatment according to c) in the autoclave or according to a) with hot air saturated with water vapour, is dampened with water or with the water/chemical mixture according to Claim 5.
9. A method according to Claim 1 to 8, characterised in that artificial hair (15) of polyester monofilar fibres is used, which has been broken down mechanically or chemically at least by 30 %-weight.
10. A method according to Claim 9, characterised in that the polyester monofilar fibres have been broken down hydrolytically, in particular by alkali solution.
11. A method according to Claim 9 or 10, characterised in that hot air temperatures of 150°C to 180°C, in particular 150°C to 160°C, are used.
12. A method according to Claim 1 to 3 and 9 to 11, characterised in that the moisture-containing agent is used in the form of a dispersion or emulsion, in which the agent bonds 0.1 to 4 % water, in relation to the fibre weight.
13. A method according to Claim 1 to 12, characterised in that before or during the treatment according to a), b) or c) described above the artificial hair (15) is coloured by the compounds set out below:

    

    

    

    
14. A method according to one of Claims 1 to 13, characterised in that through the use of chemical agents, in particular carriers, the plastic deformation point can be lowered to 50 to 100 °C.

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