KR100840437B1 - Low friction toothbrush - Google Patents

Abstract

FIELD OF THE INVENTION The present invention relates to toothbrushes for use in brushing teeth and methods of brushing teeth using such toothbrushes, which are used in hairbrushes prepared from compositions containing thermoplastic polymer resins with slip agents.

Toothbrush, low friction, bristles, thermoplastic resin, slip

Description

Low Friction Toothbrush {LOW FRICTION TOOTHBRUSH}             

This application claims priority to US Provisional Application No. 60 / 237,302, filed October 2, 2000.

The present invention relates to a toothbrush and a method for cleaning teeth. In particular, the present invention relates to the use of compositions containing thermoplastic polymers and slip agents to produce filaments for use as bristles in a toothbrush.

Hairs for use in toothbrushes were typically made from filaments made from thermoplastic polymers. There is a continuing need to improve the cleaning efficacy of bristles made from such polymeric filaments. The present invention relates to a method of improving the cleaning efficacy of such bristles by reducing the friction coefficient experienced when the bristles are in contact with the teeth. A useful means of reducing the friction coefficient experienced when the bristles are in contact with the teeth is to prepare the bristles from filaments made from a composition containing the thermoplastic polymer and the slip agent.

U.S. Pat. No. 5,462,798 ("Gueret") discloses a brush used as an applicator for thick liquid cosmetic products such as nail polish or mascara. The hair or hair of this brush is made from plastics containing slip agents. The presence of a slip agent reduces the wettability of the applicator's hair, limiting the adhesion of the product to the hair. This condition improves the tendency of the product to remain on the applied substrate rather than hair, and promotes the distribution of thicker product layers on the substrate.

The Geret patent does not mention the use of hair or mocks to clean teeth. However, the inventors have found that using bristles made from filaments made from a composition consisting of a thermoplastic polymer and a slip agent reduces the friction coefficient experienced when the bristles are in contact with the teeth to an extent that the bristle efficacy of the bristles is improved.

Summary of the Invention

In one aspect, the present invention includes a toothbrush for use in brushing teeth having bristles made from a composition containing a thermoplastic polymer resin with a slip agent.

In another aspect, the present invention provides a toothbrush having a hair prepared from a composition containing (a) a thermoplastic polymer resin with a slip agent, and (b) applying the toothbrush to the surface of one or more teeth to brush the teeth. Include how to wipe it.

The toothbrush of the present invention has been found to have excellent cleaning efficacy, in particular between teeth, because of the presence of slip agents in the filaments from which bristles are made.

1 shows a side view of a toothbrush.

2 shows a sectional view of a toothbrush.                 

3 shows a top view of the toothbrush.

4 shows a side view of a toothbrush.

5 shows a side view of a toothbrush.

6 shows a twisted mock toothbrush.

7 shows a simulated toothbrush wound up.

8 shows a cross-sectional view of a simulated toothbrush wound up.

9 shows an interfacial friction system.

The filaments used in the present invention for bristle preparation are polyamides, polyesters, polyolefins, fluoropolymers, polyurethanes, polyvinylchlorides, polyvinylidene chlorides, styrenic polymers and copolymers, and any compatible mixtures thereof. It can be prepared from a wide variety of well known thermoplastic polymers, including. Polyamides are preferred, some of which are nylon 6, nylon 11, nylon 6,6, nylon 6,10, nylon 10,10, and nylon 6,12. Polyesters useful for the manufacture of filaments include polybutylene terephthalate and polyethylene terephthalate, and blends thereof. Among many polyolefins, polypropylene is preferred. In the above, nylon 6,12 is most preferred.

The polymer (s) from which the filaments are made in the present invention, such as nylon, may have an intrinsic viscosity of about 0.9 to about 1.5 as measured at m -cresol according to ASTM D-2857.

Slip agents for use in the present invention, when added to the polymer to form the composition from which the filaments are made, will reduce the coefficient of friction experienced by the filaments in contact with the teeth when the filaments are used as bristles in the toothbrush. Examples of slip agents useful in the preparation of such compositions are fluorinated olefin polymers, boron nitride, molybdenum disulfide, graphite, fullerene and talc. Of course, fluorinated olefin polymers such as poly (tetrafluoroethylene) are preferred. The slip agent is at least about 0.5% by weight, preferably at least about 1% by weight, more preferably at least about 2% by weight, and at most about 10% by weight, based on the total weight of the composition of the polymer and the slip agent. It is used in the composition in an amount of about 6% by weight or less, more preferably about 4% by weight or less.

Filament production can be accomplished using an extruder, and various types of extruders, such as twin screw extruders, are available from manufacturers such as Werner and Pfleiderer. The polymer in granule form is fed by volume or gravimetrically from the feeder device into the extruder. The slip agent is fed through a side port from a separate feeder and blended with the polymer at 150 to 285 ° C. in an extruder. Alternatively, the slip agent may be premixed or preblended so no separate feed system is required. The polymer and slip agent are mixed as a melt in the extruder and the resulting composition is metered into a spin pack with a die plate. The composition is filtered and extruded through holes in the die plate to produce filaments of various shapes and sizes.                 

The cross-sectional shape of the filament is determined by the shape of the die plate hole, and may be any shape such as circular, elliptical, rectangular, triangular or any regular polygonal shape, or the filament may be irregular, non-circular in shape. The filaments may be hard, hollow, or contain multiple longitudinal voids in the cross section. Each time the extruder is turned, a die plate with holes of various shapes can be used to produce any mix of cross-sectional shapes. By varying the size of the die plate holes, one or more diameter filaments can be made simultaneously. In the toothbrush of the present invention, the use of rigid, circular outer strand filaments having substantially uniform cross-sectional dimensions is preferred.

Alternatively, the filaments used in the present invention can be produced by melting or solution spinning.

In the extrusion process, the filament strands are released from the die plate and then solidified in a quench water bath and then transported through a series of draw rolls for stretching to 1.5-6 times their original length. The filaments are elongated according to a repetitive schedule of linear velocity, including periods of acceleration and deceleration, and uniform recovery periods. Stretching is performed between two roll sets by operating the second roll set faster than the first roll set to increase the longitudinal strength of the filament. The stretched filaments can then be heated to induce partial crystallization to give good bending recovery. Thermal curing is typically performed in a gas (e.g. by blowing hot air into the filament for about 30 to about 120 seconds) or in a liquid bath (e.g. by passing the filament into the oil bath for about 2 to about 10 seconds). . The filaments are then wound on a winding machine such as a drum or spool.

Another aspect of the invention involves the use of a seed / core filament, wherein the sheath is from a polymer mixed with a slip agent, while the core is from a pure polymer without the addition of a slip agent. By placing the slip agent on the sheath, more desirable slip agent is present on or near the surface of the filament, resulting in a desirable effect of reducing friction. The sheath surrounds the core in coaxial or concentric form. The polymers used in the cores and sheaths may be the same or different, but must be compatible because proper adhesion must be made between the cores and sheaths. Nylon 6,12 is preferred as the seed material.

Seed / core filaments are typically produced by coextrusion using two extruders that share a common spin pack. The polymer used to make the core is sent from the first extruder to the center of the spin plate holes, and the composition used to make the seed is sent from the second extruder to the outside of the spin plate holes.

As mentioned above, the sheath / core filaments produced from multiple sources of flowable polymers or polymeric compositions can be distinguished from filaments that are only strands because the strands of filaments are produced from flowable polymeric compositions of a single source. Such single-stranded outer strand filaments may be called monofilaments. The filaments for use in the present invention may be seed / core filaments or monofilaments, but monofilaments are preferred.

The filaments for use in the present invention may be straight, bent, annular or bowed, tapered towards the ends, feathered, cut off or sagging. Preference is given to straight filaments having smooth, circular or blunt ends.

The filaments for use in the present invention are at least about 1 mil, preferably at least about 2 mils, more preferably at least about 2.5 mils, and at most about 15 mils, preferably at most about 10 mils, more preferably about 5 mils It has a diameter of mill or less, or a maximum cross-sectional dimension. One mil is 0.025 mm.

Filaments for use in the present invention have a (1) tensile modulus as measured by ASTM D-638 of about 100 to about 1000 kpsi, preferably about 400 to about 700 kpsi; (2) the tensile strength measured according to ASTM D-638 is about 10 to about 100 kpsi, preferably about 40 to about 80 kpsi; (3) the elongation measured by ASTM D-638 is about 1 to about 100%, preferably about 10 to about 50%; (4) Tynex® Nylon Filament Technical Data Report No., available from EI du Pont de Nemours and Company. The bending recovery rate measured by the mandrel bending method described in Bend Recovery of Tynex and Herox Nylon Filaments in September 5, 1971 is about 80 to about 100%, preferably about 92 to about 100%. .

The filaments for use in the present invention may contain other additives or have a coating, provided they do not interfere with the action of the slip. For example, the filaments may contain antimicrobial additives or therapeutic agents.                 

Filament is used as the bristles of the toothbrush in the present invention. Toothbrushes can be made by techniques known in the art, including staple sets, ferrules and filaments, metal pieces, fusion, or subassembly techniques. In toothbrushes, filaments often gather together as a hair to form a hair bundle. Filaments of different colors, diameters, polymer compositions, lengths and shapes can be gathered into one bundle to achieve a particular brush feature or appearance.

Brush head color is often important in toothbrushes. The filaments used in the present invention may have any desired color obtained by adding pigments, dyes or colorants to the composition from which the filaments are made (which should not interfere with the action of the slipper). Filament bundles can be created containing random changes in color and hue. Thus, hair bundles with color or hue changes can be produced within and / or between bundles, whereby a brush with attractive visual effects can be produced, or a hue difference is chosen to emphasize a particular end product characteristic. .

The term toothbrush herein refers to any type of device of any shape that allows the use of bristles to brush teeth. 1 to 3, a typical manual toothbrush 2 is shown, wherein the bristles 6 of one or more bundles 4 are generally perpendicular to the toothbrush head 8, which is a fixed, flat or essentially flat surface. Extends. The bundle 4 will have a plurality of hairs 6 made according to the invention, and the head 8 will typically have a plurality of bundles 4. The head 8 is attached to the toothbrush handle 10, and the head 8 and the handle 10 make up the toothbrush body 12. The shape of the bundle 4 and the head 8 may vary and be elliptical, bent convex, bent concave, flattened, serrated ("V"), or any other desired form. Can be. The toothbrush of FIG. 1 contains bundles oriented in a straight matrix, but the bundles can be arranged in any manner, for example in a diagonal orientation or in a continuous matrix that is deflected from the preceding matrix, respectively. Although the lengths of the hairs are shown to be substantially the same in the illustrated embodiments, the hairs may be cut into any desired length, different lengths, other shapes (eg, grooved), or other preferred shapes. The length of the hair protruding from the toothbrush head will typically be substantially uniform and will be about 5 to about 15 mm, preferably about 8 to about 14 mm. In addition, the axes of the head 8 and the handle 10 may be on the same or different sides. Brushes such as those shown in FIG. 1 may also be adapted for motorized operation.

Alternatively, the toothbrush of the present invention may be circular or cylindrical in shape, with the hair extending radially in a number of directions from the central axis toward the circumference around the central axis. For example, as shown in FIGS. 4 and 5, the cylindrical toothbrush body 14 has first and second opposing axial ends 16, 18 and generally cylindrical sidewalls 20. A spiral groove 22 is formed in the cylindrical side wall 20, which extends from the end 16 to the end 18. The hair 24 is fixed in the helical groove and extends from the cylindrical sidewall. Multiple spiral grooves, which may optionally be cut off, could also be used for this purpose. Although not shown, a variant of this embodiment may be to cut the longitudinal grooves parallel to the central axis at the cylindrical sidewalls and secure the wool to their respective longitudinal grooves. The grooves described above can be standardized in a rigid cylindrical toothbrush body or, if the toothbrush body is hollow, the drive settled in the groove can be secured from the interior of the toothbrush body.

Alternatively, in the toothbrush of the present invention having a circular or cylindrical shape, fastening means other than the toothbrush body may be used to fix the hair extending in multiple directions from the central axis toward the circumference around the central axis. For example, as shown in FIG. 6, cylindrical sole 26 may be formed by twisting, overlapping, or winding two or more parent subcomponents, such as sole subcomponents 28, 30, 32. Any suitable design of injector 34 may be used to mold the parent sub-parts together. The twisted parent subparts may be joined together by a fast cure adhesive or solvent applied by the device 36 at the junction where the parent subparts gather. Other fastening techniques such as extrusion, heat fusion and friction fitting of polymeric materials can be used.

FIG. 7 shows a variant of the embodiment of FIG. 6, wherein the sole 38 is made by spirally winding two strands of fastening material 40, 42 into the wool 44. The twisting device 46 takes three separate feeds, creates a retaining device from a fixed material (eg, a wire), secures the wool to the retaining device, and produces a spirally wound sole 38. 8 shows a cross section of the sole 38. The cross section of the sole 26 will have a similar appearance. This type of toothbrush is sometimes called an interdental toothbrush.

In the toothbrush of the present invention having a circular or cylindrical shape in which the hairs extend radially in a number of directions from the central axis to the circumference around the central axis, the portion of the simulation projecting from the central axis is about 0.5 to about 6 mm in length, preferably May be about 1 to about 4 mm. The term toothbrush is not limited to any particular embodiment illustrated or discussed herein above, and is described, for example, in US patent application Ser. No. 09 / 092,094, which is incorporated herein in its entirety and forms a part thereof. It can be manufactured from the parent subpart, as described.

The beneficial effects of the present invention are demonstrated by the series of examples described below. The embodiments of the present invention on which the examples are based are for illustrative purposes only and do not limit the scope of the present invention. The meaning of the examples is better understood by comparing embodiments of the invention with particular controlled combinations that do not have the superior features of the invention.

The compositions tested in the examples were prepared by blending nylon 6,12 with a masterbatch, and nylon 6,12 was modified by the addition of slip agents such as poly (tetrafluoroethylene) ("PTFE"). The PTFE used was Dupont's Teflon® MP1400 or MP1600 Micropowder and was used in 30% by weight of the masterbatch. The average particle size of the Teflon MP1400 micropowders was 7-12 microns, and the average particle size of the Teflon MP1600 micropowders was 4-12 microns. Contorol included a test of nylon 6,12 with no slip agent added.

EXAMPLES AND CONTROL EXAMPLES In both cases, the blended composition, or nylon itself, is melted and mixed in an extruder, then metered by a melt pump and sent through spin packs and spinneret plates to form circular strands. The strands were quenched in water and then heated above the glass transition temperature of nylon and drawn to 3 to 5 times the initial length to obtain the stretched filaments. The filaments were then thermoset in air at 150-180 ° C. to give the type of bending resilience required for the toothbrush filaments. The filaments were then coated and packaged with a surface lubricant.

The filaments produced in the manner described above were tested to determine the coefficient of friction by the interfacial friction test described below, and also the toothbrush was used as the manufactured hair. Each toothbrush was a 44 bundle, flat trimmed toothbrush made by the staple set process, similar to that shown in FIG.

The filament sizes tested and the content of the compositions tested in the examples are shown in Table 1 below, indicating the amount of Teflon MP1400 or MP1600 micropowder in the final composition, with the remainder of each composition being nylon 6,12. Since Control Examples A and B were each made from nylon without the addition of a slip agent, they are shown to not contain Teflon micropowders in Table 1.

Amount and Filament Size of the Teflon Micropowders of Examples 1-7 and Control Examples A and B Type of Micro Powder % By weight of micropowder Filament size Example 1 MP1400 2% 8 mils Example 2 MP1400 4% 8 mils Example 3 MP1600 2% 8 mils Example 4 MP1600 4% 8 mils Control Example A none none 8 mils Example 5 MP1600 One% 7 mils Example 6 MP1600 2% 7 mils Example 7 MP1600 4% 7 mils Control Example B none none 7 mils

The filaments were tested in Examples 1-7 and Control Examples A and B to determine the coefficient of friction by the interfacial friction test. Friction is resistance to the relative motion of two bodies in contact, caused by immobility at the interface of each material from which the two bodies are made. (i) The ratio of the force required to maintain a uniform velocity of one body relative to the other body to (ii) the vertical pressure between the surfaces is the coefficient of friction, which is a unitless value. The coefficient of friction by the interfacial friction test is determined using an interfacial friction meter.

The interfacial friction system is shown in FIG. 9. It measures the coefficient of friction when the material (in this case filament) comes into contact with the material and when the material (filament) comes in contact with the polished chromium surface. When making filament / filament measurements, a sample of filament is wound on a paper core or tube 48 mounted on a rotating mandrel 50. A loose filament 52 made from the same material spans the filament covered core 48. One end of the spanned filament 52 is attached to a strain gauge 54, such as a Statham transducer, and the other end is attached to weight 56. The weight is effective to keep the filament spanned tight against the core 48, but may be any amount that does not compromise the performance of the filament spanned or overload the strain gauge. 30 grams is the typical amount of these weights. The filament covered core 48 rotates at a speed of 0.0016 cm / s to 32 cm / s. The tension created by the movement of the filament-covered core 48 across the spanned filament 52 is measured by a strain gauge and the friction coefficient value is calculated from the tension data. For filament / metal measurements, the same procedure as described above is followed except that the loose filament 52 is placed over the polished chromium surface on the mandrel instead of the filament covered core 48.                 

The results of the filament / filament interfacial friction test of Examples 1 to 4 and Control Example A are shown in Table 2 below. In Table 2, the speeds shown are the different speeds (cm / s) of the mandrel where the measurements were taken. These results show that at each rate at which the measurements were made, the filaments used in Examples 1-4 containing slip agent experienced a lower coefficient of friction than the filaments used in Control Example A containing no slip agent. The lower coefficient of friction is due to the presence of the slip agent in the filaments used in Examples 1-4, because the filaments covered and the filaments covered are more than in the case of Control Example A in which filaments containing no slip agent were used. Indicates less friction between the cores.

Result of filament / filament interface friction test 0.0016 cm / s 0.0032 cm / s 0.0320 cm / s 0.3200 cm / s 3.200 cm / s 32.0000 cm / s Example 1 0.25 0.25 0.24 0.24 0.23 0.26 Example 2 0.23 0.22 0.22 0.22 0.22 0.24 Example 3 0.24 0.24 0.23 0.22 0.22 0.24 Example 4 0.21 0.20 0.20 0.20 0.20 0.22 Control Example A 0.38 0.40 0.56 0.50 0.36 0.40

The results of the filament / metal interfacial friction test of Examples 1-4 and Control Example A are shown in Table 3 below. In Table 3, the speeds shown are the different speeds (cm / s) of the mandrel where the measurements were taken. These results show that at each rate at which the measurements were made, the filaments used in Examples 1-4 containing slip agent experienced a lower coefficient of friction than the filaments used in Control Example A containing no slip agent. The lower coefficient of friction is due to the presence of the slip agent in the filaments used in Examples 1-4, between the filament spanned and the metal surface than in the case of Control Example A where filaments containing no slip agent were used. Indicates less friction.

Result of filament / metal interfacial friction test 0.0016 cm / s 0.0032 cm / s 0.0320 cm / s 0.3200 cm / s 3.200 cm / s 32.0000 cm / s Example 1 0.22 0.21 0.22 0.23 0.26 0.34 Example 2 0.21 0.22 0.22 0.22 0.23 0.31 Example 3 0.21 0.21 0.21 0.23 0.24 0.32 Example 4 0.20 0.20 0.21 0.23 0.24 0.32 Control Example A 0.32 0.31 0.33 0.37 0.47 0.69

The results of the filament / metal interfacial friction test of Examples 5-7 and Control Example B are shown in Table 4 below. In Table 4, the speeds shown are the different speeds (cm / s) of the mandrel where the measurements were taken. These results show that at each rate at which measurements were made, the filaments used in Examples 5-7 containing slip agent experienced a lower coefficient of friction than the filaments used in Control Example B containing no slip agent. The lower coefficient of friction is due to the presence of the slip agent in the filaments used in Examples 5-7, because of the presence of the slip agent in the filaments, Indicates less friction.

Result of filament / metal interfacial friction test 0.0016 cm / s 0.0032 cm / s 0.0320 cm / s 0.3200 cm / s 3.200 cm / s 32.0000 cm / s Example 5 0.12 0.11 0.11 0.13 0.16 0.34 Example 6 0.12 0.11 0.12 0.12 0.14 0.33 Example 7 0.11 0.10 0.10 0.10 0.11 0.23 Control Example B 0.14 0.13 0.14 0.16 0.24 0.44

As a toothbrush, toothbrushes were prepared using the filaments of Examples 5-7 and Control Examples A and B, respectively. Each toothbrush was tested to determine the interproximal access efficacy (IAE) of brushing. Test devices are described in Access to interproximal Tooth Surfaces by Different Bristle Designs and Stiffnesses of Toothbrushes , Scand. J. Dent. Res. 1979: 87: 424-430, according to the designs of Nygaard-Ostby, Edvardsen and Spydevold. Test techniques for evaluating brushing efficacy included an independent assessment of each toothbrush with vertical and horizontal brushing movements with a brushing weight of 250 grams for the tooth shape simulating the front and back of the tooth. All toothbrushes were stored at a temperature of 67-70 ° F. for at least 48 hours before testing. Brushing was done by placing the hair at 90 ° to the tooth surface. The brushing device was set to brush for 15 seconds with 2 brushings per second for a 50 mm brushing distance. The maximum width of the brush or IAE was recorded on pressure sensitive paper located around the front or back of the simulated tooth. The various tests for each toothbrush were repeated four times.

The results of the test determining the IAE are shown in Table 5 below. In Table 5, four types of tests are named AV, PV, AH and PH. AV is forward vertical (ie, vertical brushing to the tooth front surface), PV is backward vertical, AH is forward horizontal, and PH is backward horizontal. For each example or control example, report the mean and standard deviation (“SD”) of the 4 iterations of each type of test and take the mean and standard deviation of all 16 tests performed on the particular toothbrush. By calculating the overall score. The reported result was measured in mm and in each case is the width of the area wiped by a particular brush.

IAE test results AV PV AH PH all Average S.D. Average S.D. Average S.D. Average S.D. Average S.D. Example 5 0.83 .05 1.11 .03 0.67 .05 0.51 .03 0.78 .23 Example 6 0.87 .05 1.11 .02 0.68 .04 0.61 .05 0.82 .20 Example 7 0.85 .06 1.13 .03 0.70 .04 0.78 .12 0.86 .17 Control Example A 0.75 .04 1.09 .03 0.68 .04 0.56 .08 0.77 .21 Control Example B 0.82 .06 1.10 .02 0.69 .05 0.56 .05 0.79 .21

The results in Table 5 show, with little exception, that the toothbrushes prepared from the composition consisting of nylon and slippers (Examples 5-7) are wider than the toothbrushes without hair slippers (Controls A and B). Indicates that the area has been cleaned. The brushes of Examples 5-7 could, with the same size brushing, wipe a wider area than the toothbrushes of Control Examples A and B, because the slip agent present in the wool of the brushes of Examples 5-7 This was because the friction experienced by the contacting hair reduced the hair's ability to move further from each brush. A larger width of the wiped area obtained by the brushes of Examples 5-7 also results in a greater IAE score, indicating that they can have greater cleaning efficiency, especially interdental efficiency, than the bristles that do not contain slip agents. .

Claims (20)

delete delete delete delete delete delete Hair prepared from a composition comprising a thermoplastic polymer resin with a slip agent, wherein the composition comprises from about 0.5% by weight to about 10% by weight of the slip agent based on the total weight of the composition of the polymer and the slip agent Toothbrush for use in cleaning teeth, including in an amount. delete 12. A toothbrush for use in cleaning teeth comprising a hair prepared from a composition comprising a thermoplastic polymer resin with a slip agent, wherein the hair extends radially in a plurality of directions from the central axis toward the circumference around the central axis. 10. The toothbrush of claim 9, wherein the toothbrush is secured by twisted wires. delete delete delete delete delete delete delete delete delete delete

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