CN118042960A - Filaments for oral care implements - Google Patents

Abstract

A filament (1) made of a material suitable for use as a bristle of an oral care implement is disclosed, wherein the filament has a non-circular cross-section in a direction perpendicular to its axis, wherein the axis refers to the longitudinal axis of the filament, characterized in that the cross-sectional shape resembles a biconcave lens having non-linear edges (2, 3) defining the maximum width (w) of the bristle, wherein the non-linear edges are curved and represent arcs of circles of radius (r), and the total width of the filament is represented by (t), wherein (t) is the diameter of the same circle of radius (r), and wherein the area of the cross-section is constant along the length of the filament.

Description

Filaments for oral care implements

Technical Field

The present invention relates to filaments or bristles for oral care implements, and in particular to toothbrushes, interdental brushes, dental floss and the like.

Background

The accumulation or build-up of plaque may lead to gingivitis. Toothbrushes are the most widely used appliances for controlling dental plaque. Toothbrushes are used to clean teeth by removing plaque and debris from surfaces, including curved outer surfaces and interproximal surfaces between teeth. Toothbrushes having multi-stage bristle profiles are believed to allow the bristles to penetrate better between teeth, thereby ensuring effective plaque removal.

Attempts to improve cleaning in the configuration and placement of bristles or bristle tufts on the brush head when designing toothbrushes are briefly described below.

One such attempt is made in EP 1,286,608 B1 (Colgate-Palmolive Company, 2008) which discloses a bristle pattern for penetration into the interproximal spaces between teeth and for enhanced cleaning of the tooth surfaces. It discloses a bristle pattern comprising an inverted "V" shaped trimming profile with its apex centered on the head.

EP 1,097,655 A2 (olgate-Palmolive Company, 2001) discloses a toothbrush having a bristle profile for improved cleaning and access to the teeth and gums. The bristle structure comprises: a population of convex bristles located at the heel of the brush head, the tooth engaging ends of the population being located in convex lines; another convex bristle group positioned at the tip of the brush head; and a population of male bristles interposed between the two populations of male bristles and having their tooth engaging ends in a female line.

Other attempts have involved the shape and arrangement of the bristles. Bristles are also referred to as filaments.

WO 95/19120A1 (P & G) discloses the use of filaments having a non-circular cross section. The filaments have a cross-section of three-chamber, four-chamber, trilobal, rectangular or hexagonal shape. These toothbrushes remove plaque better.

US2003/115707 A1 (Edward) discloses bristles having helical grooves along their longitudinal axes to increase grinding and enlarge the surface area of the bristles for cleaning. The bristles have shallow spiral grooves along their longitudinal axes so that the entire bristle, including the tips of the bristles and their longitudinal axes, acts as part of the cleaning surface of the bristle. The surface area of the bristles for cleaning is enlarged. The diameter of each groove is approximately one-fourth the diameter of the bristle.

JP 2009-055983A (Sasaki Hiroshi) discloses a toothbrush which performs effective cleaning without the distal ends of the bristles coming into contact with the teeth. A plurality of circular depressions are formed dispersedly on the outer surface of the wire of the bristle. When the wires are brought into contact with the tooth surfaces, they elastically deform and are inserted into the gaps between the teeth, thereby brushing through the gaps. When the wire is deformed, the edges of the recess protrude toward the tooth surface, and the sharp edges rub against the surface of the tooth with the reciprocating motion of the toothbrush as if the stain is scraped off with a spatula, so that the stain on the tooth surface can be reliably removed in a short time. The grooved bristles are combined into tufts and mounted on a suitable platform such that when the surface to be cleaned is scrubbed with a toothbrush having the improved bristles of the present invention, the bristles twist and bend and in the process the axes of the bristles scrape against the surface to be cleaned and agitate the fluid in and around the area to be cleaned, thereby increasing the cleaning capacity of the toothbrush.

EP 3 721 752 A1 (TAIKI CORP LTD, 2020) discloses a cosmetic bristle material which consists of S-twisted or Z-twisted filaments made of synthetic resin. The monofilaments have a cocoon-shaped cross section in a direction orthogonal to the fiber axis. Cocoon-shaped shape means a shape resembling a rice block (Rice Bale) of cocoons spun by silkworms; a rectangular shape gradually shrinking in the center portion (intermediate portion).

It is well known that teeth are often exposed to a variety of stains, including many food and beverage preparations. Most of the time, this contact is unavoidable and the teeth become stained over a period of time.

The problem of stains can be solved by using specially formulated toothpaste. Or toothbrushes for this purpose are present.

For example, US2012/246857 A1 (Kato Keisuke) discloses the use of core-sheath bristles.

US2006/070635 A1 (P & G) discloses a cosmetic brush having a longitudinal handle and a plurality of bristles, each bristle extending from a base associated with the handle and terminating in a free end, each bristle having an outer wall and a longitudinal axis. Each bristle has at least one external depression oriented in a direction substantially parallel to the longitudinal axis of the selected bristle.

EP 3 251 548 A1 (P & G) discloses a filament for an oral care implement having a longitudinal axis and a substantially cross-shaped cross-sectional area extending in a plane substantially perpendicular to the longitudinal axis. The cross-shaped cross-sectional area has four protrusions and four channels. The projections and channels are arranged in an alternating manner. Each channel has a concave curvature formed by adjacent and converging projections. The concave curvature has a radius and each tab end is rounded to form a curvature.

We have determined that the problem of stains can be better addressed by using an oral care implement comprising filaments according to the present invention. Filaments are also interchangeably referred to as bristles.

It is an object of the present invention to provide an oral care implement that can provide better stain removal, preferably better removal of at least some stains, such as tea, coffee, wine and other stains commonly associated with teeth.

Disclosure of Invention

According to a first aspect of the present invention, a filament 1 made of a material suitable for use as bristles of an oral care implement is disclosed, wherein the filament has a non-circular cross-section in a direction perpendicular to its axis, wherein the axis refers to the longitudinal axis of the filament, characterized in that the cross-sectional shape resembles a biconcave lens having a non-linear edge defining the maximum width of the filament, wherein the non-linear edge is curved and represents an arc of a circle of radius (r), and the total width of the filament is represented by (t), wherein (t) is the diameter of the same circle of radius (r), and wherein the area of the cross-section is constant along the length of the filament.

According to a second aspect of the present invention, there is disclosed a head for a toothbrush comprising the filaments of the first aspect.

According to a third aspect of the present invention, a toothbrush comprising the filament of the first aspect is disclosed.

Drawings

FIG. 1 is a cross-sectional view of one embodiment of a filament according to the present invention.

Detailed description of the drawings

FIG. 1 is a cross-sectional view of one embodiment of a filament according to the present invention. The filaments (1) are made of a material suitable for use as bristles in an oral care implement. The filaments have a non-circular cross-section in a direction perpendicular to their axes. An axis refers to the longitudinal axis of the filament. The cross-sectional shape resembles a biconcave lens having nonlinear edges (2, 3) defining the maximum width of the bristles. The nonlinear edge is curved and represents an arc of a circle of radius (r). The total width of the filaments is denoted by (t), and (t) is the diameter of the same circle of radius (r). The maximum width is denoted (w).

Detailed Description

As used herein, the term "comprising" includes the terms "consisting essentially of … …" and "consisting of … …". Where the term "comprising" is used, the listed steps or options need not be exhaustive. Unless otherwise indicated, numerical ranges expressed in the format "x to y" are understood to include x and y. Any particular upper value or amount may be associated with any particular lower value or amount when any range of values or amounts is specified. Except in the examples and comparative experiments, or where otherwise explicitly indicated, all numbers are to be understood as modified by the word "about". All percentages and ratios contained herein are by weight unless otherwise indicated. The indefinite articles "a" or "an" as used herein and their corresponding definite articles "the" mean at least one, or one or more, unless otherwise specified. The various features of the invention mentioned in the individual sections above apply, where appropriate, to other sections mutatis mutandis. Thus, features specified in one section may be combined with features specified in other sections where appropriate. Any section headings are added for convenience only and are not intended to limit the disclosure in any way. The invention is not limited to the embodiments shown in the drawings. Accordingly, where features mentioned in the claims are followed by reference signs, those reference signs have been included for the sole purpose of increasing the intelligibility of the claims and are in no way limiting the scope of the claims. The embodiments are intended to illustrate the invention and are not intended to limit the invention to those embodiments per se.

Filament yarn

The filaments of the present invention are made of a material suitable for use as bristles for an oral care implement. The filaments have a non-circular cross-section in a direction perpendicular to their axes. The term shaft refers to the longitudinal axis of the filament. The terms filament and bristle are used interchangeably throughout this specification.

Typically the filaments of toothbrushes or other oral care implements have a circular cross-section. The direction perpendicular to its axis means the direction perpendicular to the longitudinal axis of the (right-angled) filament.

In the filaments of the present invention, the cross-sectional shape resembles a biconcave lens having nonlinear edges defining the maximum width of the bristles. The concept of lenses is discussed in Physics. Biconcave lenses are symmetrical in both their horizontal and vertical axes. Both faces of the biconcave lens can be considered to be initially part of a sphere. In a typical biconcave lens, the edge defining the maximum width is linear. However, in filaments according to the invention, the cross-sectional shape resembles a biconcave lens having nonlinear edges defining the maximum width of the bristles. The nonlinear edge is curved and represents an arc of a circle of radius (r), and the total width of the filament is represented by (t), where (t) is the diameter of the same circle of radius (r). The area of the cross section is constant along the length of the filament. Preferably, the filaments are free of S-twist or Z-twist along their axes. Filaments with S-and Z-twist are disclosed in EP 3 721 752 A1.

Preferably, the oral care implement of the present invention is a toothbrush, an interdental brush, a toothpick or a dental floss. The toothbrush is preferably a manual toothbrush. Or it may be an electric toothbrush.

Preferably, the material is a natural material, a synthetic polymer or a biopolymer.

When the material is a synthetic polymer, it is preferably a thermoplastic material selected from polyoxymethylene, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, polyethylene oxide, polypropylene oxide, polytetrahydrofuran, polytetramethylene ether glycol, polyolefin, polyalkylene, polypeptide, polyamide, polyamine or polyester.

Preferably, the polyester is polyethylene terephthalate (PET), polyethylene furanoate (PEF), polybutylene terephthalate (PBT), polytrimethylene terephthalate (PTT), polyglycolic acid (PGA), polylactic acid (PLA), polycaprolactone (PCL), polyethylene adipate (PEA), polyhydroxyalkanoate (PHA), polyhydroxybutyrate (PHB), polyethylene naphthalate (PEN), poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), polycondensates of 4-hydroxybenzoic acid and 6-hydroxynaphthalene-2-carboxylic acid (VECTRA).

Preferably, the polyamide is nylon 6 or nylon 6,12. A preferred nylon brand is 6/12 nylon, available from E.I.Du Pont de Nemours and Company, forIs sold under the trade name of (c).

The filaments preferably have a thickness (width) of 0.10 to 0.30mm, more preferably 0.15 to 0.25mm, still more preferably 0.18 to 0.23 mm. The filaments may be any color.

Preferably, the filaments comprise a benefit agent or active agent. Benefit agents are typically added for marketing claim purposes, such as claims for enhanced cleaning, which do not require verification.

The active agent is typically included in an amount sufficient to achieve the desired effect, which can be demonstrated by clinical studies or similar experimental science. The same materials may be included in amounts sufficient to be referred to as benefit agents or active agents, depending on the level or weight incorporated into the bristles. Various methods are known to be able to include one or more such agents in the filaments.

A variety of antimicrobial active compounds may be used. These actives can be generally classified as halogenated hydrocarbons, quaternary ammonium salts and sulfur compounds. Halogenated hydrocarbons include halogenated derivatives of salicylanilide, carbonyl, bisphenol, diphenyl ether, anilines of thiophenecarboxylic acids, and chlorhexidine. Quaternary ammonium compounds include alkylammonium salts, pyridinium salts, and isoquinolinium salts. Sulfur-reactive compounds include thiuram sulfides and dithiocarbamates.

Among the halogenated salicylanilides, the following derivatives may be mentioned:

5-bromo-salicylanilide 4', 5-dibromo-salicylanilide

3,4', 5-Tribromosalicylanilide

6-Chloro-salicylanilides

4', 5-Dichloro-salicylanilide

3,4', 5-Trichloro-salicylanilide 4', 5-diiodo-salicylanilide

3,4', 5-Triiodo-salicylanilide

5-Chloro-3-trifluoromethyl-salicylanilide

5-Chloro-2-trifluoromethyl-salicylanilide

3, 5-Dibromo-3, -trifluoromethyl-salicylanilide

3-Chloro-4-bromo-4' -trifluoromethyl-salicylanilide

2', 5-Dichloro-3-phenyl-salicylanilide

3', 5-Dichloro-4' -methyl-3-phenyl-salicylanilide

3', 5-Dichloro-4' -phenyl-3-phenyl-salicylanilide

3,3', 5-Trichloro-6' - (p-chlorophenoxy) -salicylanilide

3', 5-Dichloro-5' - (p-bromophenoxy) -salicylanilide

3, 5-Dichloro-6' -phenoxy-salicylanilide

3, 5-Dichloro-6' - (o-chlorophenoxy) -salicylanilide

5-Chloro-6' - (o-chlorophenoxy) -salicylanilide

5-Chloro-6' -beta-naphthoxy-salicylanilide

5-Chloro-6' -alpha-naphthyloxy-salicylanilide

3,3', 4-Trichloro-5, 6' - β -naphthoxy-salicylanilide;

Halocarbonyl groups are represented by 3, 4' -trichloro-carbonyl groups and 3,3', 4-trichloro derivatives and 3-trifluoromethyl-4, 4' -dichlorocarbonyl groups.

Bisphenol is represented by:

2,2' -methylenebis (4-chlorophenol)

2,2 '-Methylenebis (4, 5-dichlorophenol) 2,2' -methylenebis (3, 4, 6-trichlorophenol)

2,2' -Thiobis (4, 6-dichlorophenol)

2,2' -Diketobis (4-bromophenol)

2,2 '-Methylenebis (4-chloro-6-isopropylphenol) 2,2' -isopropylidenebis (6-sec-butyl-4-chlorophenol)

Examples of quaternary ammonium compounds are:

Cetyl pyridinium chloride

Diisobutylphenoxy ethoxy ethyl dimethyl benzyl ammonium chloride

N-methyl-N- (2-hydroxyethyl) -N- (2-hydroxydodecyl) -N-benzyl ammonium chloride cetyl trimethyl ammonium bromide

Octadecyl trimethyl ammonium bromide

Oleyl dimethyl ethyl ammonium bromide

Lauryl dimethyl chloroethoxy ethyl ammonium chloride

Lauryl dimethyl benzyl ammonium chloride

Alkyl (C8-C18) dimethyl (3, 4-dichlorobenzyl) -ammonium chloride

Lauryl pyridinium bromide

Isoquinolinium lauryl bromide

N- (lauroyloxyethylcarbamoylmethyl) pyridinium chloride;

Examples of thiocarbamates and thiurams are:

ethylene bis-dithiocarbamate disodium salt (Nabam)

Ethylene bis-dithiocarbamic acid diammonium (amabam)

Zinc ethylenebis-dithiocarbamate (ziram)

Ethylene bis-iron dithiocarbamic acid (ferbam)

Manganese ethylenebis-dithiocarbamate (manzate)

Tetramethylthiuram disulfide

Tetrabenzyl thiuram disulfide

Tetraethylthiuram disulfide

Tetramethylthiuram sulfide

From the viewpoint of safety and effectiveness, preferred antibacterial agents are as follows:

4', 5-dibromosalicylanilide

3,4', 5-Tribromosalicylanilide

3,4', 5-Trichlorosalicylanilide

3, 4' -Trichlorocarbonyl substituted

3-Trifluoromethyl-4, 4-dichlorophenyl carbonyl group

2,2' -Methylenebis (3, 4, 6-trichlorophenol)

2,4 '-Trichloro-2' -hydroxydiphenyl ether

Brevibacteriin

N-methyl-N- (2-hydroxyethyl-N- (2-hydroxydodecyl) -N-benzyl ammonium chloride

Cetyl pyridinium chloride

Particularly preferred are:

2,3', 5-tribromosalicylanilide

Chlorhexidine digluconate

Chlorhexidine diacetate 4', 5-dibromosalicylanilide

3, 4' -Trichlorocarbonyl substituted

2, 4' -Trichloro-2-hydroxydiphenyl ether

Cetyl pyridinium chloride

Most preferred among the halogenated hydrocarbons is 2, 4' -trichloro-2-hydroxydiphenyl ether (commonly known as triclosan), and most preferred among the quaternary ammonium salts is cetylpyridinium chloride. In fact, the combination of these two actives allows for a wide range of antibacterial activity in the toothbrushes of the present invention.

According to a second aspect, a brush head for a toothbrush is disclosed, comprising the filament of the first aspect. The brush head may comprise said filaments, wherein a certain group of filaments in a so-called tuft has a cross-section as disclosed herein. In these embodiments of the invention, the bristles may be used to clean the teeth and mouth of a user. Different embodiments of the present invention may include different bristle designs to achieve different types of cleaning, such as standard, sensitive or whitening. The user can interchange the brush head with different bristle designs to achieve different types of cleaning while using the same handle. Thus, the present invention may allow a user greater flexibility in their tooth cleaning habits without having to have multiple different toothbrushes.

According to a third aspect, a toothbrush comprising the filament of the first aspect is disclosed. Toothbrushes according to the present invention can have a variety of shapes and designs. A typical toothbrush is characterized by a head having bristles in tufts, a neck having a first end and a second end, and a handle having a front end and a rear end. The toothbrush may or may not include additional features such as elastomeric members for better cleaning, grip enhancing features, and tongue cleaners located on the back of the head. A suitable tongue cleaner has been described in WO 2016/058820 (A1).

All parts of the toothbrush according to the invention are preferably constructed integrally together from the same plastic material. The most preferred plastic material is a polyolefin, such as low density polyethylene. Advantageously, the plastic material has a melt index of more than 5, preferably 6 to 30, optimally 10 to 25g/10 minutes.

The dimensions of the toothbrush according to the invention are maintained such that the toothbrush preferably has a length in the range of 170 to 200mm, a width of the handle in the range of 10 to 20mm and a thickness in the range of 5 to 15mm. Thus, the surface area to volume ratio, which is an important parameter in determining the ergonomics of the toothbrush, is maintained to be similar to or better than that of standard mass toothbrushes. The ratio of surface area to volume of the toothbrush according to the invention is preferably in the range of 0.2 to 0.3, whereas standard mass toothbrushes known in the art have a ratio of at most 0.2.

The plastic material used to form the toothbrush is preferably selected from various grades of polypropylene, styrene-acrylonitrile, polymethyl methacrylate, acrylonitrile-butadiene-styrene, or thermoplastic elastomers. The most preferred materials are polypropylene and thermoplastic elastomers.

Method for preparing an oral care implement

The oral care implement may be made by any method commonly understood by those skilled in the art. The bristles or filaments may be tufted into the bristle bearing face of the brush head using typical staple technology or by fusion. During the staple erecting process, a small group of bristles is folded over the nickel-silver staples and forced into cylindrical holes in the toothbrush to form bristle tufts. After the tufting, the tufts are polished through a series of sanding discs that remove any burrs or sharp edges. The toothbrush head in which bristles are anchored using the staple set bristle setting process requires deeper holes and a relatively thicker head. Or the bristles may be anchored to the bristle bearing surface of the brush head using other non-stapling techniques. One such method involves fusing bristle tufts into the bristle bearing surface of a brush head by heating the bristle tufts and the brush head, which are then bonded together. In another known method, the ends of the bristle tufts are pre-positioned in an injection mold prior to introducing the material forming the toothbrush head, and then material is injected around the bristle tuft ends, thereby locking the bristle tufts in place in the bristle bearing face of the toothbrush head. After tufting, the bristles are cut to the desired contour in a finishing step, and then the free tips of the bristles are rounded. The toothbrush is then packaged.

The toothbrush of the present invention may be provided in a kit packaged with a dentifrice. The advantage of this system is that it enhances the delivery of active substances and flavors to the teeth and gums based on the unique configuration and materials of the toothbrush. Dentifrices of the present invention may generally include humectants, abrasives, thickeners, flavorants, and therapeutically active agents.

Claims (10)

1. A filament (1) made of a material suitable for use as a bristle of an oral care implement, wherein the filament has a non-circular cross-section in a direction perpendicular to its axis, wherein the axis refers to the longitudinal axis of the filament, characterized in that the cross-sectional shape resembles a biconcave lens having non-linear edges (2, 3) defining the maximum width (w) of the filament, wherein the non-linear edges are curved and represent arcs of circles of radius (r), and the total width of the filament is represented by (t), wherein (t) is the diameter of the same circle of radius (r), and wherein the area of the cross-section is constant along the length of the filament.

2. The filament according to claim 2, wherein the filament is free of S-twist or Z-twist along the axis.

3. The filament according to one of claims 1 or 2, wherein the material is a natural material, a synthetic polymer or a biopolymer.

4. The filament according to claim 3, wherein the synthetic polymer is a thermoplastic material selected from the group consisting of: polyoxymethylene, polyethylene glycol, polypropylene glycol, polytetramethylene glycol, polyethylene oxide, polypropylene oxide, polytetrahydrofuran, polytetramethylene ether glycol, polyolefin, polyalkylene, polypeptide, polyamide, polyamine or polyester.

5. The filament of claim 4, wherein the polyester is polyethylene terephthalate (PET), polyethylene furanoate (PEF), polybutylene terephthalate (PBT), polytrimethylene terephthalate (PTT), polyglycolic acid (PGA), polylactic acid (PLA), polycaprolactone (PCL), polyethylene adipate (PEA), polyhydroxyalkanoate (PHA), polyhydroxybutyrate (PHB), polyethylene naphthalate (PEN), poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV), and polycondensates of 4-hydroxybenzoic acid and 6-hydroxynaphthalene-2-carboxylic acid (VECTRAN).

6. The filament of claim 5, wherein the polyamide is nylon 6 or nylon 6,12.

7. The filament according to any one of claims 1 to 6, wherein the filament comprises a benefit agent or active agent.

8. The filament according to one of claims 1 to 7, wherein the oral care implement is a toothbrush, an interdental brush, a toothpick or a dental floss.

9. A brush head for a toothbrush comprising filaments according to one of claims 1 to 8.

10. Toothbrush comprising a filament according to one of claims 1 to 8.