ited States Patent [191 Thornton Sept. 24, 1974 [54] INTERDENTAL TOOTH CLEANER AND 2,821,202 I/ 1958 Davis 132/93 METHOD U MAKING SAME 3,247,857 4/ 1966 Kanbar 132/93 Primary ExaminerG. E. McNeil] Assistant Examiner-Gregory E. McNeill Attorney, Agent, or Firm-Ernest M. Junkins 5 7 ABSTRACT A continuous length of interdental tooth cleaner consisting of textured yarn that is composed of deformed filaments that are covered with a hardened resin to stiffen them and in which the yarn is processed to increase its normal bulkiness.
8 Claims, 4 Drawing Figures INTERDENTAL TOOTH CLEANER AND METHOD FOR MAKING SAME The present invention relates to a length of yarn which is used like dental floss for insertion into crevises formed between adjacent teeth to clean the crevices. In most instances the adjacent crowns of the teeth forming the crevice are quite close together, if not touching, and the cleaner to be effective must pass through the adjacent crowns into the crevice. However, as most crevices are wider than the crowns, the cleaner, if small enough to be capable of passing past the crown, is not large enough to essentially fill the crevice to enable effective cleaning action by the removal of particles therein and the scrubbing of the crevice forming surfaces of the adjacent teeth, while if large enough to effectively clean the teeth, will not pass through the crowns.
 In my co-pending application Ser. No. 138,501, filed Aug. 21, 1971, now abandoned, there is also disclosed a teeth cleaner having a bulky portion and a reduced diameter string portion. While such a cleaner has been found to be completely satisfactory, it was not capable of being processed as a continuous length cleaner so that the user may sever from a supply the length of the bulky portion which was desired to be used.
It is accordingly an object of the present invention to provide an interdental tooth cleaner which may be made in a continuous length and yet be effective in removing particles and cleaning the crevices between adjacent teeth.
 Another object of the present invention is to provide a teeth cleaner which may be easily inserted into the crevice past theclose crowns by having its thickness decreased, but yet revert to an enlarged bulky state in the crevice to substantially fill the crevice so as to engage the surfaces of the teeth forming the crevice.
 A further object of the present invention is to provide a method for making a continuous length dental cleaner from a length of textured yarn which achieves the above objects and in which the bulkiness of the cleaner is increased over that which the yarn originally possessed.
 In carrying out the present invention, the interdental cleaner consists of a continuous length of textured yarn that has been coated with a hardened resin to increase its stiffness and memory. One form of yarn which may be utilized in a 600 denier textured yarn formed of nylon filaments in which the filaments have been processed to be permanently crinkled or otherwise deformed from their normal straight condition. The yarn filaments are covered with a hardened covering, such as nylon resin.
 The process of making the cleaner not only involves providing the hardened covering but also includes the step of increasing the bulkiness of the yarn. This is achieved by exerting an elongating force on the yarn that tensions the yarn and causes the filaments to become somewhat less entangled after a removal of the tension so that the normal and inherent bulkiness of the yarn is increased. The covering may be applied as a liquid during the tensioning or after and then hardened with the hardening occurring while substantially no tension is exerted on the yarn and thus the covering serves to maintain the increased bulkiness thereof.
 In use, a desired length of cleaner is severed from a continuous supply thereof and the user stretches, by tensioning, a short portion between his fingers which minimizes the thickness of the cleaner. This stretched portion is passed through the contact points at the crowns of adjacent teeth defining the crevice and into the crevice. The tension is then released which enables the cleaner to assume its normal bulky state wherein it substantially fills the crevice. One end of the cleaner is then pulled, to draw the clenaer through the crevice and in so doing, cause dislodgement of particles therein while also tending to scrub the surfaces of the teeth defining the cavity.
 Other features and advantages will hereinafter appear.
In the drawing:
 FIG. 1 is a diagrammatic representation of the method of forming a continuous length of interdental tooth cleaner of the present invention.
FIG. 2 is a representation of a length thereof.
 FIG. 3 is a view showing the applying of an elongating force to reduce the diameter of the cleaner for insertion past the crowns.
 FIG. 4 is a view of a further embodiment of the method of making the cleaner.
 Referring to the drawing, the continuous length of interdental tooth cleaner of the present invention is generally indicated by thereference numeral 10 and is wound as a continuous length on a spool 11 after being formed by the process that includes the apparatus shown in FIG. 1.
 As shown in FIG. 1, a strand of continuous length 600 denier textured yarn is drawn from aspool 12 through asqueeze block 13 by a set ofrollers 14. The yarn between thesqueeze block 13 and therollers 14 is stretched by a tension of perhaps 3 pounds. The yarn is then sprayed by asprayer 15 with nylon resin that is dissolved in a solvent such as alcohol so that the filaments of the yarn become covered with the liquid. The solvent is evaporated by use of a heat dryer 16 which by eliminating the solvent causes the nylon resin to form a hardened covering on the filaments. A pair offeed rollers 17 draws the yarn through the sprayer l5 and the dryer 16 after which it is subsequently wound on the spool 11 as the continuous length interdental teeth cleaner.
 Therollers 14 and 17 are preferably mechanically interconnected with therollers 17 being driven at a slightly lesser rate than therollers 14. The lesser rate is such as to exert substantially no tension on the yarn between the rollers which enables the yarn to contract to a shorter length than it had when withdrawn from thespool 12. However, its bulkiness is greater. The spool 11 winds thecleaner 10 without any substantial tension thereon so that the cleaner on the spool 11 is at its normal bulky state.
 In use, a user cuts the desired length of the cleaner 11) from the spool 11 and places a portion thereof, such as aportion 18, between the fingersand exerts a pulling force thereon as shown in FIG. 3, which substantially reduces the thickness of the yarn by basically straightening the filaments to eliminate the deformities of the filaments that cause the yarn to be textured. Theportion 18 is then easily inserted through the contact point at the crowns of the teeth in the same manner as normal straight filament dental floss. The user thereupon releases the tension and the cleaner assumes its normal bulky condition as shown by the portions thereof that are not under tension. A slight pull on the end of the cleaner draws it through the crevice and as it is in its normal bulky condition, it substantially fills the crevice to dislodge any particles of food while also exerting a cleaning action on the surfaces of the teeth defining the crevice.
 It has been found that where a continuous filament strand of textured nylon yarn of about 600 denier is used, it will stretch approximately twice its length with a small pull of perhaps two or three pounds. In addition, as shown by theportion 18, the pulling shrinks the diameter from approximately Va to about 1/48 inch so that the tensioned diameter is perhaps l/6 of the normal or relaxed diameter. While one specific size of yarn has been disclosed, it is contemplated that other sizes may also be employed.
 Shown in FIG. 4 is another embodiment of the present invention in which the liquid resin is contained within abath 19 located between therollers 14 and thesqueeze roll block 13. The yarn is immersed in thebath 19 to have its filaments coated. It may then be either passed beneath thesprayer 15 for additional contact with the liquid resin or not and then passed through to the dryer 16 to cause evaporation of the solvent. In either event, the tension on the yarn at the dryer is less than the tension between therollers 14 and thesqueeze block 13 and preferably essentially no tension exists so that the yarn, while having its nylon coating hardened, will be in a relaxed state and thus will have an increased bulkiness over that which the yarn has when drawn from thespool 12. The bulkiness is caused by the filaments becoming somewhat less entangled after being stretched and the hardened covering maintains this state of a larger diameter orbulkier cleaner 10. However, the hardened covering still enables a tension to produce a small diameter straight portion, such as theportion 18 for easy insertion into the crevice.
 lt accordingly will be appreciated there has been disclosed an interdental tooth cleaner which may be formed as a continuous length of textured yarn that has had its filaments covered with a hardened covering. The user severs a desired length of the cleaner from a supply and any portion of the cleaner may have its bulkiness substantially reduced merely by exerting a small tension thereon so that the reduced diameter portion may pass into a crevice between the points of contacts of the crowns of adjacent teeth. Within the crevice, the cleaner returns to its normal bulky condition to substantially fill the crevice and enable the filaments of the yarn with their hardened covering to be pulled through the cavity to dislodge particles therein and also to rub against the tooth surfaces.
 Variations and modifications may be made within the scope of the claims and portions of the improvements may be used without others.
I claim:
 1. An interdental tooth cleaner comprising a length of textured yarn formed of a plurality of filaments that have been individually permanently deformed and crinkled throughout the length of the cleaner and a covering of hardened material on the filaments to increase their stiffness and memory, said length normally being bulky by the filaments being maintained deformed and crinkled but becoming essentially straightened by an elongating force that decreases its bulkiness and in which said length returns to being bulky upon removal of the elongating force.
 2. The invention as defined in claim 1 in which the filaments of the yarn are somewhat disentangled to increase the bulkiness of the cleaner.
 3. The invention as defined in claim 1 in which the filaments are formed of plastic material and in which the covering material is also a plastic material.
 4. The method of making a continuous length of interdental tooth cleaner comprising the steps of supplying a continuous length of textured yarn formed of a plurality of individually deformed and crinkled filaments, increasing the bulkiness of the yarn by somewhat disentangling the filaments and forming a hardened coating on the somewhat disentangled filaments.
 5. The invention as defined in claim 4 in which the step of increasing the bulkiness includes the step of exerting a stretching force on the yarn and then decreasing the stretching force.
 6. The invention as defined in claim 5 in which the forming of a hardened coating includes the step of applying a liquid resin to the filaments and in which there is the step of hardening the coating while the filaments have the decreased stretching force applied thereto.
 7. The invention as defined in claim 6 in which the liquid resin is applied while the stretching force is applied to the filaments.
 8. The invention as defined in claim 6 in which the step of applying the liquid resin occurs after the stretching force has been applied to the filaments and then decreased.