GB2166950A - Heatable flexible hair curlers - Google Patents

Abstract

An elongated flexible hair curler having a central core molded within a pliable viscoelastic polymer heat-retaining body. The hair curler comprises a generally elongated structure having rounded ends and is capable of being bent into a plurality of positions including being bent through an angle of substantially 180 DEG back upon itself in order to retain a hair tress wound thereon curler without the aid of hair clips. The heat retaining body is capable of being heated by an external means to a predetermined temperature and able to retain the heat for a predetermined time in order to facilitate the setting of curls in hair. <IMAGE>

Description

SPECIFICATION Heatable flexible hair curlers Field of the Invention This invention relates two hair curlers for having hair tresses wound thereon in order to impart a curl to the hair. In particular, this invention relates to elongated flexible hair curlers.

Description of the Prior Art Elongated flexible hair curlers have been known for quite some time. Such curlers generally comprise cylindrical bodies made of resilient material such as foamorsponge rubberand have a wire orsoft metaí core embedded within the body along the axis ofthe curler. An elongatedflexible curler is much longer than an inflexible curler in order to enable itto be bent over on itselfto retain a hair tress wound thereon. This avoids the necessity of a clip to hold the hair as is required with inflexible curlers. Elongated flexible curlers also may be bent in a variety of positions after hair is wound thereon and thus may impart a variety of waves to the hair. The metal core enablesthe curlerto be bent and to retain the position it is placed in until it is bent into another position.

Examples of one type of elongated flexible curler are shown in U.S. Patent Nos. 1,619,743 and Re. 15,363 showing a wire core within a cylindrical pliable rubber covering encased in a fibrous cover. U.S. Patent Nos.

2,061,817 and 2,542,601 show flexible hair curlers having a central metal core and a compressible sponge rubber, solid natural or synthetic rubber body molded around the core. More recent prior art is shown in U.K. Patent Application No. GB 2,111,382 disclosing an elongated curler having a central wire core surrounded by a sleeve and polyethylene foam jacket and having end caps covering the wire ends.

U.K. patent application GB 2,067,898 shows a curler having a "pipe cleaner" core element extending beyond the curler body in order to enablethe ends to be bent back over the body.

None of the aforementioned prior art elongated flexible curlers is identified as being suitable for being heated and for retaining sufficient heat for a sufficient time period to facilitate setting a curl in the hair. Foam rubber curlers are unsuitable for heat retention because they have an open-celled structure with many air pockets which do not retain heat well. While some relatively solid material is required to enhance heat retention, solid rubber curlers are unsuitable because they are relatively hard to the touch, inflexible, and continued exposure to heat would tend to deteriorate the rubber. Natural and synthetic rubber like that used in the curler referred to in U.S. Patent No.2,542,601 generally has durometer reading on the order of 30-100 Shore A.This amount of hardness makes the material not sufficiently flexible orelasticforsatisfac- tory curler applications and causes the body material to tend to straighten the wire. Because ofthe hardness ofthe body material the core wire must be relatively large to overcome the inflexibility of the rubber. Also, the rubber curler disclosed in 2,542,601 does not address the issue offlammability ofthe body material because that curler is not designed to be heated. In a heatable curler nonflammability is important. There is no suggestion in this patentofwhatmaterial may be used which has all ofthe desirable characteristics.

Furthermore, there is no suggestion in the aforemen tioned prior art patents as to how to overcome the well-known heat-aging propensity of rubber-based compounds.

U.S. Patent No.2,074,816 shows an elongated flexible hair curler having an absorbent casing filled with a material such as calcium oxide which when moistened generates heat.Thecurlerdisclosed in thins patent is incapable of generating heat in use with dry hair. Additionally, the use of a discrete chemical composition within the curler requires extra effort and expense to insure integrity of the calcium oxide compartment throughout the life ofthe curler.

It is an object ofthis invention to provide an elongated flexible curler capable of being heated and retaining sufficient heatfor a sufficient time to facilitate setting a curl in hair wound on the curler.

!t is a further object ofthis invention to provide an elongated flexible curler capable of being heated dry and of retaining heat for a sufficienttime in use with either dry or dampened hairto facilitate setting a curl in the hair.

It is yet another object of this invention to provide a heatable elongated flexible curler capable of repeated and continued exposureto high haircurling tempera- tures without significant deterioration, capable of being bent substantially 180 and retaining such bent position, and having a durometer reading of approximately 30-70 Shore 00.

SUMMARY OF THE INVENTION These and other objects ofthis invention are achieved by improvements in a flexible haircurler having a central elongated core capable of being bent into a plurality of positions and of retaining any such position, the improvement comprising a viscoelastic polymer body molded about said core and the ends thereof, said body being heatable by external means to a predetermined temperature and able to retain heatfora predetermined time. The product ofthe invention may, because the viscoelastic polymer is sufficiently supple, be bent into an infinite number of positions with the relative stiffness of the wire holding each position as desired.

In the preferred embodiment the central core is a wire having a predetermined size on the order 16 gauge the ends ofwhich are bent into loops in order to assist in the retention ofthe wire within the molded body and in order to inhibit movement of the wire within the body to prevent the wire from penetrating the ends thereof.

In alternate embodiments, this invention may also comprise a structure having a central elongated core surrounded by an open-celled foam impregnated with a predetermined gel having good heat retention qualities and encased within a flexible tube in order to preserve integrity of the impregnated foam/gel composition.

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 shows a plan view of a flexible hair curler constructed in accordance with the principles of this invention.

Figure 2 shows a side elevational view of Figure 1.

Figure 3 shows a cross-sectional view of Figure 2 taken along the line 3-3.

Figure 4 is a sketch showing several possible configurations into which the flexible hair curlers may be bent in actual use.

Figures SA and 5B are end and side cross-sections of an alternate embodiment of the invention.

DESCRIPTION OF THE PREFERRED EMBODIMENT Referring nowto Figure 1 there is shown a plan view ofthe preferred embodiment ofthe invention showing a flexible hair curler lOin an elongated unbent position. By reference to Figure 4 itwill be understood that, in operation, after a hairtress is wound upon the curler it be bent back upon itself or in a variety of positions in orderto retain the hairtress thereon withoutthe aid of clips.

Curler 10 includes a central wire core 12 (shown in phantom in Figures 1 and 2) the ends ofwhich are bent into loops 14 and 16. Wire 12 is embedded within body 18 and may be either bare or coated with vinyl orthe like. Curler 10 is manufactured in a mold (not shown) by having wire 12 retained upon core pins (not shown) while body 18 is injected or cast into the mold. After body 18 has set, curler is removed from the mold.

The removal of the core pins leaves apertures 20 and 22 which may remain or may be filled with a suitable plug material. The core pins have semi-circular recess (the complement of which is best seen in Figure 3) within which wire 12 is held while the mold sets.

Itwill be understood thatthe body 18 must be made of a pliable heat-retaining material able to be heated by an external means to a predetermined temperature suitableforhairsetting and able to retainthe heatfora predetermined time sufficientto set a curl in the hair wound upon the curler 10. It has been found that such a material should be able to rnpeatedlywithstand high temperatures of approximately 100, centigrade for relatively long periods oftime and must be able to withstand repeated exposure to such temperatures without significant deterioration. Such material should also be relatively nonflammable and nontoxic inorderto be suitableforconsumer use.Additionally, the material should have a nonsticky surface and be sufficientlyflexibleand pliable in ordertoenable itto be beht into a variety ofpositions including being bent back upon itselfto retain the hairwound thereupon.

The material should be a relatively solid material ratherthan afoam strncturein orderto have the foregoing beneficial characteristics and also have a high heatcapacity and be ableto retain the heatfor a significant period oftime while conducting itto the hairwound upon the curler. Rubber alone, which was disclosed in the prior art, is not soft enough orflexible enough to achieve these functions. Even if it is softened with plasticizers the combination remains unsuitable for consumer use because theflammability increases and the plasticizers are extremely corrosive to materials with which the roller may come in contact (forexample,varnish on wood surfaces).The material must have all of the aforementioned characteristics and in addition should feel softtotheusertoenhance comfort and facilitate handling.

Ithas beenfoundthatcertain polyurethane based compounds possess all ofthe aforementioned desirable properties and are suitable for use in flexible hair curlers. Because oftheir low durometer readings and viscoelastic properties, these materials enable use of smaller diameterwire than prior art rubber curlers. For example, the compound Sorbothane available from Sorbothane, Inc., 2144 State Route 59, P.O. Box 178, Kent, Ohio 44240 is a viscoelastic polymer which has a very low durometer reading of 30-70 Shore 00.

Sorbothane is generally described in U.S. Patent No.

4,346,205. Other polyurethane compounds may be suitable. For example, Mearthane Products Corp., 70 Glen Road, Cranston, R.l. 02920 manufactures a viscoelastic polymer known as Mearthane which is similarto Sorbothane.

The curler is intended to be used with an external heatsourcesuch asthatdescribed in acopending application entitled Hairsetter For Flexible Hair Curlers filed concurrently herewith and assigned to the assignee hereof. Afterthe curlers are heated in such an external heat source they may be used to curl hair in the conventional manner, some examples ofwhich are shown in Figure 4.

Itwill beunderstoodthat,whilethepreferred embodiment of the invention comprises essentially two parts-a core wire and a heatable polyurethane based composition -the advantages ofthe invention are achievable by other embodiments. Thus, as shown in Figures SAand SB the central core wire could be embedded in a conventional open-celled cylindrical foam shell 30 which could be impregnated with a heatable gel or other composition and the entire curler could then be encased in,forexample, a silicone rubbertube 32 or other soft, pliable liquid-impervious casing material. The gel could alternatively be injection moldedwiththefoam and covered with a plastisol orothercoating by spraying or dipping.

It will be understood by those skilled in the artthat numerous other improvements and modifications may be made to the preferred embodiment ofthe invention disclosed herein without departing from the scope hereof. For example,thesurface of any ofthe embodiments disclosed herein may be coated with flocking material to enhance the softfeel of the curlers and to assist in gripping the hair. The principles ofthis invention could also be embodied in hair curlers of various cross-sectional shapes (elliptical, polygonal, etc.) and various overall shapes (toroidal, elliptical, etc.). For example, a hair curler could incorporate a spiral groove or ridge along its length orvarying diameters along its length.

Claims (6)

1. In a flexible hair curler having a central core, said curler capable of being bent into a plurality of positions and of retaining any such bent position, the improvement comprising: a viscoelastic polymer body molded about said core, said body being heatable by external means to a predetermined temperature and able to retain heatfor a predetermined time sufficientto enable said curler to be used to curl hair.

2. In a curler for curling hair comprising a core of wire or the like capable of being bent into a plurality of positions and capable of thereafter substantially maintaining the position without additional force, an elongated casing or coating surroundingsaid core and having end portions covering the ends thereof, a pliable material filling said casing or coating, the improvement comprising: a heat-retaining material embedded substantially throughout said pliable material for being heated, for retaining heatfor a period oftime sufficient to enable said curlerto be used to curl hairandforcommunicat- ing said heat to said casing or coating.

3. An improvementaccording to claim 1 wherein said body is totally encased within a pliable casing or coating.

4. An improvementaccording to claim 1 wherein the surface of said bodyisflocked.

5. An im provement according to cla im 2 wherein said casing or coating is flocked.

6. An improved curler as claimed in claim 1 or2 substantially as described with reference to any Figure or Figures of the accompanying drawings.