CN112535546A

CN112535546A - Trilobal yarn for dental floss, dental floss comprising same and use of trilobal yarn for manufacturing dental floss

Info

Publication number: CN112535546A
Application number: CN201910900290.8A
Authority: CN
Inventors: G·D·L·鲁
Original assignee: Proffer Industry And Trade Co ltd
Current assignee: Proffer Industry And Trade Co ltd
Priority date: 2019-09-23
Filing date: 2019-09-23
Publication date: 2021-03-23

Abstract

The present invention relates to a yarn for dental floss made of hollow trilobal cross-section filaments comprising 90-99% polypropylene and 1-10% other polyolefin resins. The invention also relates to a process for the production of a yarn made of hollow trilobal cross-section filaments. The invention also relates to a dental floss comprising a hollow trilobal cross-section filament, and to the use of a hollow trilobal cross-section filament for the manufacture of a dental floss. The yarn of the invention has a linear density or count in the range of 400 and 1200dtex and is twisted at a twist level of 10-160 twists per meter.

Description

Trilobal yarn for dental floss, dental floss comprising same and use of trilobal yarn for manufacturing dental floss

Technical Field

The present invention relates to a continuous filament yarn (filamentyarn) having a trilobal cross-section for use in dental floss, and to dental floss made from such yarn.

Background

Plaque, also known as dental plaque, microbial plaque, oral biofilm, dental biofilm or plaque biofilm, is a biofilm formed by bacteria and food residues formed on the surface of teeth, which is a major cause of dental caries and gum disease. In the early stages, this plaque is a sticky colorless deposit, but if it is not removed daily, it grows and hardens to form tartar. Dental floss and/or dental tape (dental tape) are important oral hygiene tools to avoid plaque.

Many types of dental floss are known to exist. There are continuous synthetic yarns made of PTFE (polytetrafluoroethylene) monofilaments between them, and dental floss made of continuous synthetic yarns made of PA (polyamide) multifilaments made of several filaments bundled together in a single cable to make a single yarn. PA flosses may be waxed or ungathered, and have a variety of flavors. PTFE monofilament slides more easily between teeth than multifilament yarns, which sometimes tear or tear. The tape is flatter and thinner with the goal of reaching a wider area, but it is more difficult to reach the interproximal spaces.

Trilobal filaments and synthetic fibers are well known for their textile applications. Filaments and fibers having a trilobal cross-section are notable for increased gloss and brightness compared to the same filaments and fibers having a circular cross-section, and this is the primary purpose of using this trilobal cross-section because light reflection is less diffuse at the yarn surface, and the reflected light is more directional due to the trilobal yarn surface geometry. The hollow cross-section serves to reduce the density of the textile material and improve the thermal insulation properties, since the hollow filaments and the internal passages within the fibers are filled with air

In the case of the present invention, the purpose of the hollow trilobal cross-section is different from those described above. In dental floss applications, the trilobal cross-section proves to be more abrasive than the traditional circular cross-section, and this property improves the efficiency of removing plaque and food debris from the interdental spaces.

The hollow trilobal cross-section yarn has a greater bulk than conventional solid circular cross-section yarns, and even than solid trilobal cross-section yarns. This increased volume has been shown to improve the removal of plaque and food debris from the interproximal spaces.

US2939201 relates to novel trilobal synthetic filaments and fibers having improved optical properties and improved stain resistance when incorporated into textile materials.

US4770938 relates to trilobal synthetic fibers for carpets having axially extending holes in each lobe, a total cross-sectional area of the fibers being about 5-12% voids, a modification ratio of the fiber cross-section being about 2-3, and an arm angle being about 15 ° -45 °, whereby fibers having improved bulk, soil fixation and resiliency are evident on carpets with face fibers of the fibers.

EP750691 relates to a melt spinning process and nylon hollow filaments and yarns made by such process, such process comprising extruding a molten nylon polymer having a Relative Viscosity (RV) of at least about 50 and a melting point (TM) of from about 210 ℃ to about 310 ℃ from a spinneret capillary orifice having a plurality of orifice segments providing a total Extrusion Area (EA) and an extrusion void region (EVA) such that the fractional extrusion void content, defined by the [ EVA/EA ] ratio, is from about 0.6 to about 0.95 and the degree of melt attenuation, defined by the [ EVA/(dpf) S ] ratio, is from about 0.05 to about 1.5, wherein (dpf) S is the spun denier per filament and (dpf) S is selected such that the denier per filament at 25% elongation (dpf)25 is from about 0.5 to about 20; drawing the plurality of melt streams from the spinneret into a quench zone under conditions such that the plurality of melt streams are substantially continuously self-coalesced into spun filaments having at least one longitudinal void and a Residual Draw Ratio (RDR) of less than 2.75; and stabilizing the spun hollow filaments to provide hollow filaments having a Residual Draw Ratio (RDR) of from about 1.2 to about 2.25.

US2011044916 relates to dental floss comprising a basic amino acid or salt thereof. The dental floss may be made of nylon or of polytetrafluoroethylene (PTFE or PTFE)

) Polypropylene, polyethylene, styrene butadiene copolymer, or combinations thereof. The polymer is melted and extruded into a fine thread like the dental floss of the present invention.

US4646766 relates to dental tape made of polypropylene. Dental tape can be made by extruding a polypropylene film in tape form onto a cooled take-off roll and then roll embossing the film through a hardened steel roll.

The brazilian patent application PI0905828 relates to a dental floss having improved tooth cleaning efficiency and improved adaptation of the interdental spaces by the presence of axially flexible protrusions, so that the secondary yarns can be penetrated by the floss movement between the teeth and, by the flexible expansion of the floss, reach the interdental spaces which cannot be reached by conventional flosses.

Disclosure of Invention

The present invention relates to a yarn for dental floss having a hollow trilobal cross-section, and the use of a trilobal filament for dental floss.

The invention also relates to a dental floss comprising a hollow trilobal cross-section filament.

The invention also relates to a method for producing a hollow trilobal cross-section filament.

Drawings

Fig. 1 is a picture of a hollow trilobal cross-section made by a microscope.

Detailed Description

One example of the invention is a yarn for dental floss made of continuous filaments with a hollow trilobal cross-section, containing 90-99% polypropylene (PP) and 1-10% other polyolefin-based masterbatch (pigment), preferably 95% polypropylene (PP) and 5% polyolefin resin, in particular Polyethylene (PE).

The dental floss of the invention comprises a yarn made of continuous filaments having a hollow trilobal cross-section, containing 90-99% of polypropylene (PP) and 1-10% of other polyolefin-based masterbatches (pigments), preferably 95% of polypropylene (PP) and 5% of a polyolefin resin, in particular Polyethylene (PE).

Some of the advantages presented by the floss of the present invention are: improved plaque removal due to filament cross-sectional shape and this improvement is additionally increased by 40% when the yarn is additivated with special pigments for this application, such as: pigment blue 15:3C.I.74160, pigment green 7C.I.74260, pigment red 149C.I.71137 and pigment white 6 C.I.77891; increased absorption of waxes and fragrances; consumer comfort and ease of use are better due to the increased filament flexibility provided by the hollow cross-section; the weight provided by the hollow cross-section yarns is lighter (for floss producers who sell floss in meters), has more volume and lighter weight.

In addition to the advantages described, the floss of the present invention elastically deforms its cross-section when forcefully passed through tight tooth spaces, making the cleaning process easier and more comfortable for the consumer when compared to conventional flosses made of solid cross-section filaments.

The yarn of the invention has a linear density or count (title) of 400-1200dtex, which is twisted at a twist level of 10-160 twists per meter to increase its strength during use. Twisted yarns provide enhanced protection against individual filaments or even entire yarns breaking or tearing when subjected to friction. In particular, for the subject matter of the present invention, the friction occurs between the yarn and the teeth during the teeth cleaning process by the consumer when the yarn is forced through the interdental spaces.

Another statement of the invention is a method for producing hollow trilobal filaments. The method comprises the following steps:

-melt spinning a multifilament using a synthetic resin as a raw material;

-feeding a raw material in the form of polypropylene particles to an extrusion melt spinning machine;

-melting the polypropylene in an extruder and, when applied, adding a pigment masterbatch (1-10%) in this step to obtain coloured yarns of different colours;

-pumping the melt through a spinneret to produce a product in the form of a continuous filament yarn;

-cooling the hot molten filaments with air to harden them, then lubricating with air, drawing, entangling the filaments and finally winding the yarn on a paper tube;

-twisting the yarn with a twist of 10-160 per meter.

The invention also relates to the use of a hollow trilobal cross-section filament for the manufacture of dental floss.

Examples

The technical data of 2 dental floss products produced by the following experiments are detailed:

TABLE 1

Claims

1. Yarn for dental floss comprising filaments with a hollow trilobal cross-section, characterized in that it comprises 90-99% polypropylene and 1-10% other polyolefin resins.

2. The yarn of claim 1 comprising 95% polypropylene and 5% polyolefin resin.

3. The yarn of any one of claims 1-2, wherein the polyolefin resin is polyethylene.

4. Yarn according to any one of claims 1 to 3, characterised in that the yarn comprises an additive selected from dyes and pigments.

5. Yarn according to any one of claims 1-4, characterised in that the yarn has a linear density or count in the range of 400 to 1200dtex and the yarn is twisted at a twist level of 10 to 160 twists per metre.

6. Dental floss comprising a hollow trilobal cross-section filament as claimed in any of the preceding claims 1-5.

7. Use of a filament yarn having a hollow trilobal cross-section as claimed in any one of claims 1 to 5 for the manufacture of a dental floss as claimed in claim 6.

8. A method of preparing the yarn of claims 1-5 by multifilament melt spinning using synthetic resin as a raw material, comprising:

-feeding a raw material to an extrusion melt spinning machine, wherein the raw material is polypropylene particles and the extrusion melt spinning machine comprises: an extruder, gear metering pump, spinneret, quench chamber, spin coater, draw roll, entangling nozzle, and winding system;

-melting the polypropylene particles in the extruder while adding a pigment masterbatch to obtain a molten mass, wherein the pigment masterbatch comprises a further polyolefin resin;

-pumping the molten mass through the spinneret to produce a product in the form of continuous hot-melt filament yarns;

-cooling the hot molten filament yarn with air, making it stiff, then lubricating with air, drawing, entangling the cooled filament yarn, and finally winding the cooled filament yarn on a paper tube;

-twisting the yarn with a twist of 10 to 160 per meter.