Claims:
We claim
1. Dental floss coated with a coating agent comprising a water-insoluble, resilient matrix which is selected from the group consisting of hydrocarbon waxes, polyethylene, polyisobutylene, polybutadiene, copolymers of butadiene and styrene, copolymers of butadiene and acrylonitrile, polyisoprene, copolymers of butadiene and isoprene, polyethylacrylate, and mixtures thereof, and a polishing agent embedded therein which is selected from the group consisting of an oxide, silicate, carbide, boride, carbonate, phosphate, sulfide or nitride of the elements: calcium, magnesium, silicon, aluminum, iron, titanium, zinc, tungsten, zirconium, tin, sodium and potassium, and their mixtures.
2. The dental floss in claim 1 wherein the polishing agent is incorporated in the matrix in a weight ratio of polishing agent ot matrix of from about 1:5 to 5.5:1.
3. The dental floss in claim 2 wherein the matrix consists of hydrocarbon wax.
4. The dental floss in claim 2 wherein the matrix consists of branched polyethylene.
5. The dental floss in claim 2 wherein the polishing agent consists of pumice.
6. The dental floss in claim 2 wherein the polishing agent consists of calcium silicate.
7. The dental floss in claim 2 wherein the polishing agent consists of calcium carbonate.
8. The dental floss in claim 2 wherein the polishing agent consists of alumina hydrate.
9. The dental floss in claim 2 wherein the polishing agent consists of zirconium silicate.
10. The dental floss in claim 3 wherein the polishing agent consists of pumice.
11. The dental floss in claim 2 wherein the matrix consists of a mixture of hydrocarbon wax and branched polyethylene and the polishing agent consists of pumice.
Description:
This invention relates to a dental floss having improved cleaning properties. More specifically this invention relates to a dental floss coated with a coating agent having embedded therein a finely divided particulate material as a polishing agent.
The dental floss of this invention combines the superior cleaning qualities of unwaxed dental floss with the advantages associated with the wax-coated floss, such as ease of unwinding from the spool and ease of insertion between the teeth, and at the same time the dental floss of this invention does not have the disadvantage of deposit buildup on the surface of the teeth associated with wax-coated flosses that are currently available. Of equal importance is the ability of this floss to polish the teeth.
The components of the dental floss of this invention by necessity are composed of materials of an inert and non-toxic nature. The yarn to be coated may be any suitable natural or synthetic yarn such as, for example, those composed of cotton, silk, linen, nylon, polyester or acrylic fibers, and various mixtures thereof. The floss may be of any suitable size or shape; it may be round or flat, and may be composed of braided, spun or twisted fibers capable of being inserted between the teeth. It is preferred that the fiber employed as the floss be a multi-filament fiber having sufficient strength so that it will not break too readily and yet should not be so firm that it cannot be easily cut. It is therefore desirable that the fibers have a break load for the total floss within the range of about 4 to 16 pounds.
The coating agent applied to the floss comprises a matrix in admixture with a polishing agent. Preferably the matrix has elastomeric properties so that the particles embedded therein will exert an even pressure on the surface of the teeth to sustain a polishing action. The particles should have the ability to float freely in the matrix and yet have the ability to recover their position so that they are not displaced from the elastomeric matrix that surrounds them. Accordingly, the matrix may comprise a natural or synthetic resilient wax, polymer, rubber, or a latex adhesive.
In order to facilitate coating of the fiber it is desirable that the matrix be in a fluid form, so that either a low molecular weight material or a solvent solution of a higher molecular weight material may be utilized in the coating process. Examples of suitable materials include the following: flexible mineral, animal or vegetable waxes such as hydrocarbon waxes, including microcrystalline waxes and paraffinic waxes, bees wax, montan wax, carnauba wax and ceresin wax; low molecular weight polyethylene, particularly branched polyethylene, polyethylene glycols, chlorosulfonated polyethylene; polybutene-based rubbers such as polyisobutylene, polybutadiene, copolymers of butadiene and styrene, copolymers of butadiene and acrylonitrile; isoprene-based rubbers such as, polyisoprene, copolymers of butadiene and isoprene; polyvinylchloride, polyvinylidene chloride; polyester-based elastomers such as poly(methylmethacrylate), polyethylacrylate; polyether-based elastomers; silicone rubbers; polyurethanes, and the like.
Preferred materials for the matrix composition are the water-insoluble, flexible materials that have good adherence to the fibers of the floss, such as, hydrocarbon waxes, both microcrystalline and paraffinic waxes, polyethylene, polyisobutylene, polybutadiene, copolymers of butadiene and styrene, copolymers of butadiene and acrylonitrile, polyisoprene, copolymers of butadiene and isoprene, polyethylacrylate, and various mixtures thereof.
Most preferred compositions include the microcrystalline and paraffinic hydrocarbon waxes, polyethylene, and their mixtures.
The polishing agent embedded in the matrix may be any inert, non-toxic, finely divided particulate material having a hardness on the Mohs' scale of at least about 2.0 and a particle size in the range of about 1 to 100 microns. For example, the polishing agent may be an oxide, silicate, carbide, boride, carbonate, phosphate, sulfide or nitride of such elements as calcium, magnesium, silicon, aluminum, iron, titanium, zinc, tungsten, zirconium, tin, sodium and potassium, and their mixtures. Particularly preferred are such materials as pumice, talc, calcium carbonate, calcium silicate, zirconium oxide, zircon, alumina, alumina hydrate and the like.
The polishing agent, such as one of the aforementioned compositions, is incorporated in the elastomeric matrix in amounts such that the elastic properties of the matrix are maintained, and that sufficient elastomeric material surrounds the particle so that the particle can float free in the matrix. It is also desirable for as large a number of the particles as possible to be exposed on the surface of the matrix so as to exert a more effective polishing action on the teeth. It is therefore preferred that the polishing agent be incorporated into the matrix in a weight ratio of polishing agent to the matrix of from about 1:5 to 5.5:1, however ratios of from about 1:10 to 10:1 may also be effectively utilized.
The coating on the fiber may be applied by any one of a number of methods known in the art. For example, the fiber can be guided through a liquid bath of the coating material wherein the material may be a polymer or a solvent solution of a polymer containing a suspension of the finely divided polishing agent, and then passed through a heated die or an extruder to remove excess polymer, and, if necessary, to cure the polymer. It is also feasible by this method to periodically lift the fiber out of the coating bath and to reimmerse it at regular intervals to obtain a floss with combination of lengths of coated and uncoated surfaces.
In another procedure, the fiber may be passed through a liquid bath of polymer or solution of the polymer, then through a die or a wire-coater, and the tacky polymer coated fiber may subsequently be guided through a fluid or a solid bed of the particulate polishing agent, and then heated to effect a cure.
It is also contemplated to be within the scope of this invention to incorporate various adjuvant materials into the coating agent, such as, coloring matter, flavoring agents, medicinals or therapeutic agents.
The following examples serve to illustrate the present invention, but the scope of this invention is not to be limited by these examples.
EXAMPLE 1
Into a flask equipped with a magnetic stirrer were added 25 grams of a microcrystalline hydrocarbon wax (Quaker State White Superflex L-500) heated to 90°C, and 25 grams of pumice (Whip Mix Corp. Italian R-400A). Unwaxed dental floss composed of nylon fiber yarn was guided through a bath of the wax mixture by means of a fork guide, and the wax-coated nylon fiber was then passed through a split brass die positioned above the coating bath so that excess wax could drip back into the bath. The die had an opening with a diameter of 0.01 inch and was heated to 90°C by means of a winding of electric tape. On leaving the heated die the wax mixture coating on the floss solidified rapidly, and the floss was subsequently wound on a spool. The dental floss prepared as described above was field tested and was found to have a very satisfactory polishing action on the teeth, without any evidence of waxy deposit remaining or abrasive action on the surface of the teeth due to the coated dental floss.
EXAMPLE 2
The procedure of Example 1 was repeated with the exception that calcium silicate was substituted for pumice as the polishing agent, and the same satisfactory results were obtained with this floss.
EXAMPLE 3
Example 1 was repeated employing zirconium silicate, (obtained from the Zirconium Corporation of America) as the polishing agent and the same satisfactory test results were obtained.
EXAMPLE 4
Example 1 was repeated employing calcium carbonate as the polishing agent, and the test results were satisfactory.
EXAMPLE 5
Example 1 was repeated with the exception that a polymeric substrate consisting of a low molecular weight branched polyethylene was substituted for the microcrystalline hydrocarbon wax, and the same satisfactory results were obtained.