KR20160003127U - Spiral filaments and the production thereof - Google Patents

Abstract

An apparatus according to the present invention for producing helical filaments comprises an extrusion unit for extruding at least one monofilament, a twisting unit for twisting at least one monofilament under its tensile stress to its longitudinal axis, Wherein the temperature control unit is designed to heat the filament before and / or after twisting the at least one monofilament and / or twisting the at least one monofilament, and wherein the thermosetting occurs and the filament has any The filaments are tensioned about their longitudinal axis in such a way that they do not have internal torsional stresses. The present invention also relates to helical filaments made by extruding and twisting monofilaments.

Description

[0001] SPIRAL FILAMENTS AND THE PRODUCTION THEREOF [0002]

The present invention relates to helical filaments, preferably to methods and apparatus for making plastic filaments, and to helical filaments. In particular, the present invention relates to filaments that can be used as bristles of brushes (e.g., toothbrushes or cosmetic brushes) and which may be made by extruding and twisting monofilaments.

In recent years, it has been confirmed that when the mother has the surface structure, the simulation brushing effect used in the brush product can be improved. While these types of motions move the surface in a stroking and sliding manner, the structures of the surface (e.g., helical coils) detach dirty particles more effectively than the mother with a smooth surface.

Is produced by twisting twill filaments having a helical profile (particularly filaments having no circular cross section). By twisting, the zone having a large cross-sectional radius is rotated in a spiral manner over the longitudinal axis of the filament to form coils that spiral around the filament. This effect can also be achieved by subsequently applying the coils or by injection into the coil shape, but this can be a problem in terms of the manufacturing process.

In addition, twisting can be advantageous in terms of appearance. For example, a helical pattern can be made over the length of the filament by twisting the filament using the two colored layers. If these layers are made of different materials with different properties, filaments with twisted circular cross-sections can be used to improve the cleaning effect due to the different surfaces.

A disadvantage of twisted filaments is that the tension that reverses the twisting effect is formed in the filament and can distort the filament and may have a negative effect on the straightness or bending resistance of the filament. With regard to distortion, it should be noted that this is mostly a kind of distortion that occurs when the tension decreases across the longitudinal axis of the filament. Due to internal torsional stresses (caused by twisting), part of the filaments or adjacent filament strands can be distorted as is observed in the manufacturing process of cables and ropes when the filaments are suspended.

It is an object of the present invention to provide an apparatus and method which can solve the disadvantages of the prior art and enable a user to manufacture a helical wrist having the same predetermined quality as a conventional wrist by a simple, inexpensive, time saving manner. In addition, the purpose of this invention is to make these models available.

This object is achieved by a device and a filament according to the claims.

A method for manufacturing a spiral filament according to the present invention comprises:

Compressing at least one monofilament,

- twisting the at least one monofilament with respect to its longitudinal axis under tensile stress, wherein the filaments are stretched before and / or after twisting and / or after twisting the at least one monofilament, And thermal processing is performed in which the thermosetting takes place and the filament has no internal torsional stress.

An apparatus according to the present invention for producing helical filaments comprises an extrusion unit for extruding at least one monofilament, a twisting unit for twisting at least one monofilament under its tensile stress to its longitudinal axis, Wherein the temperature control unit is designed to heat the filament before and / or after twisting the at least one monofilament and / or twisting the at least one monofilament, and wherein the thermosetting occurs and the filament has any The filaments are tensioned about their longitudinal axis in such a way that they do not have internal torsional stresses.

Filaments according to the present invention produced by the above-described method or apparatus are characterized in that the polymer chains of the filaments are twisted but the filaments have no internal torsional stresses. Torsional stresses can be measured not only by photoelasticity, but also by observing the tendency of the filaments to be observed, e.g., not twisted or twisted with other filaments, in the absence of tensile stress. The twisting of the polymer chains can be determined, for example, by measuring with polarization or other polarizing radiation.

According to the present invention, it is possible to solve the drawbacks of the prior art, and to provide a device in which a user can manufacture a spiral wrist with a pre-settable quality equal to that of a conventional wrist by a simple, inexpensive, time saving manner.

1 is a view showing a twisted filament.
Figure 2 schematically shows a preferred apparatus for producing twisted filaments.
Figures 3 and 4 are views showing different cross-sections of twisted filaments.

According to a preferred embodiment, the monofilament has a cross section different from the circular shape. In this manner, filaments having a helical surface structure can be produced. Preferably, the monofilament produced by extrusion also has a circular zone with at least one protrusion, such as ribs having an elliptical, star or polygonal cross-section or cross-section, for example axially parallel.

According to another preferred embodiment, the monofilament has a circular cross section, but in particular the monofilament may comprise at least two different components extending parallel to one another along the longitudinal axis of the monofilament. The components can be altered in terms of color, material or additives of the raw materials. In this manner, filaments having a uniform surface with a helical structure can be produced.

According to another preferred embodiment, only a single monofilament is used.

According to another preferred embodiment, one or more monofilaments are used and twisted two or more monofilaments to obtain a helical surface structure. With respect to this embodiment, if the temperature during the heat treatment step of one of the heat treatment steps is such that at least one surface of the monofilaments is heated above the glass transition temperature and adheres to at least one additional monofilament, some applications It is advantageous for.

According to another preferred embodiment, the at least one monofilament comprises a matrix comprising at least one first plastic material (matrix material) and at least one rib extending in the longitudinal direction of the filament, wherein the ribs comprise a second plastic material Rib material) and held in a matrix in a form-fitting manner or held together by a material bond or force fit connection. Preferably, at least one of the ribs has a radially outwardly tapered cross section, e.g. a triangular or droplet shaped cross section, so that the ribs are particularly radially sharpened in their outer cross section. Preferably, the at least one rib is provided with an undercut at its end embedded in the matrix, preferably in a widened leg surrounded by a matrix material. This ensures good shape fit connection between the ribs and the matrix. Preferably, the monofilament comprises a plurality of ribs, and the ribs are preferably evenly distributed around the monofilament.

Alternatively, the first region of the matrix can have an annular cross-section and surrounds a second region of at least one interior of the matrix, the second region being made of a third plastic. In this way, the performance characteristics of the monofilament or the manufactured motor can be adjusted better for the desired purpose. According to a preferred embodiment, the matrix also comprises at least one additional matrix material, the matrix materials differing in particular with regard to their material, color, stability or elasticity.

Preferably, the matrix material or rib material is formed of a rigid thermoplastic polyester, in particular polybutylene terephthalate (PBT), and a soft thermoplastic resin and in particular a thermoplastic elastomer may be preferred in some applications.

According to a preferred embodiment, at least one rib is colored in at least some sections so as to be distinguishable by color from the rest of the monofilament. In this manner, it is possible to show the user that the monofilament is twisted to prevent confusion when using the monofilament.

Heat treatment is used to relax the tension in the filament. It is therefore advantageous if the heat treatment is carried out at a particular point only for a short portion of the filament, in particular before or after twisting, or less than one second after twisting, otherwise the untwisted zone due to non- There may be relaxation of stresses from unwanted twisting of < RTI ID = 0.0 > The short portion is particularly less than 5 m, preferably less than 1 m, in particular less than 20 cm. Thus, the filaments are not heated in a wound form, but the filaments pass through the heating unit or through the heating unit so that only one portion is heated at a particular time and another portion of the same length is heated at another point in time.

According to a preferred embodiment for the heat treatment, the filaments are guided over the heated surface before, during or after twisting. The surface is curved according to a preferred embodiment, in particular in the form of a rotationally symmetrical body (for example a cylinder) or a body with a helix profile. This type of body is also referred to below as a "heating roller ". Preferably, the filament is guided at least once around the heating roller.

The temperature of the heated filament (or its surface) is preferably somewhat lower than the glass transition temperature of at least one of the materials used in the filament. In this connection, "somewhat" means in particular that the temperature is at least 80% (preferably at least 90%) of the glass transition temperature and is below the glass transition temperature. Preferably, the temperature is at least 1 占 폚 lower than the glass transition temperature or less than 99.9% of the glass transition temperature.

According to a preferred embodiment, the temperature of the surface (e.g. the surface of the heating roller) corresponds to the temperature mentioned above. However, in some applications it may be advantageous for the temperature of the surface to correspond to the glass transition temperature or to be higher than the glass transition temperature. In particular, it can be ensured that the filament (or its surface) in this manner has a temperature as described above after heat treatment, unless the filament is guided very quickly onto the surface or thermal bonding is not very effective. The filament may also preferably have a temperature above the glass transition temperature, depending on the application. Preferably, the temperature is 110% of the glass transition temperature.

According to a more preferred embodiment, the surface is straight or the rounded portions may have straight portions. In this manner, the filaments can be heated while proceeding into the position where the filaments are twisted, or the filaments can be heated in a simple manner during twisting if the twisting is carried out in the stretched state of the filaments.

According to a more preferred embodiment, the thermal application medium is a fluid. In this case the filaments are guided and heated through a bath of the thermal application medium.

Preferably, the thermal application medium is a solid (e. G., The surface described above) or liquid and not a gas. There is therefore preferably direct contact with the thermal application medium and not the gas during the heat treatment. In this way, thermal bonding is excellent, heating is fast and easy to control.

According to a preferred embodiment, the heat source is a heat radiator (infrared radiator). This has the advantage of providing very rapid temperature control. This kind of infrared radiator is particularly advantageous in the case of direct contact with the heat application medium, in which the medium ensures a basic heating and the heat radiator ensures an additional application of heat which can be controlled quickly.

Preferably, the temperature and duration of the heat treatment can be adjusted so that the filament is heated to its core.

According to a preferred embodiment, the heat treatment is carried out before twisting. In this case, in the preferred embodiment, the temperature and duration of the heat treatment are adjusted such that the filament is not heated to its core but less than 70% of the circumferential radius of the filament cross-section reaches a temperature slightly below the glass transition temperature. In this case, the twisting of the outside of the filament is larger than the twisting of the core, wherein additional heat treatment after twisting is advantageous for fixing.

According to a preferred embodiment, at least one filament is predrawn and especially further pulled out after extrusion and at a further step prior to twisting, and in order to stabilize the at least one monofilament, the monofilament is preferably heat shrunk Lt; / RTI > Particularly, the preliminary drawing of the molded filament and the subsequent additional drawing result in a filament having a strength characteristic known from conventional non-molded filaments.

It is necessary to ensure that the hair of the specific brush has a predetermined stability or rigidity. If the polymer chains of the filament core extend parallel to the longitudinal direction of the filament and the polymer chains are twisted at the outer portion of the filament, it is possible to adjust the resilience or stiffness of the twisted filament in the preferred embodiment of the present invention. By varying the depth at which twisting occurs, the simulated resilience or stiffness can be adjusted in a desired manner using a predetermined thickness and a predetermined material. The variation in depth at which twisting occurs can be approximately determined in the twisting process by the number of twists per second at the known running speed of the filament. However, it should be noted that the winding is fixed only after the heat treatment. If the already heated filament is twisted, the twisting depth also depends on the temperature and residence time in the twisting zone.

According to a preferred embodiment, the heat treatment is carried out before twisting, whereby the externally applied temperature and temperature duration of the filament are determined to reach the desired depth during subsequent twisting. Of course, the inventor recognizes that due to the continuous and different process of twisting the polymer chains in the filament, there must be a certain transition between the twisted chain and the longitudinally parallel chain. Thus, the "depth at which twisting occurs" refers to the depth at which polymer chains are twisted beyond 90 ° after externally applied 360 ° twisting.

For example, it is possible to measure the twisting by spectroscopic analysis, the depth of the twisting being determined by the sharpening of the filament. It is possible to measure (for example by microscope) in a simple optical manner, provided that the filament has a zone extending to a surface layer composed of a material optically distinguishable from the core (e.g. a color stripe). However, there are also measuring methods which use suitable polarizations or other radiation, especially for uniformly colored filaments, to determine the arrangement of polymer chains in plastics.

It should be noted that the variable cleaning effect of the end ends and the spiral flank can be advantageously combined with one another in many cases. This also applies to toothbrushes, massage brushes, mascara brushes, brooms, sweeping rollers, rust removal brushes and other brushes. Also, individual spiral wool or bundle-coupled spiral wool may be used in a particularly advantageous manner, such as interdental cleaners that have a much better cleaning effect during back and forth movement in interdental spaces such as continuously varying sections . Such an interdental cleaner may not only be torn even if it is caught in a narrow gap, but may be easily removed by twisting. Finally, if the section of the helix is correspondingly rounded, a very gentle and sensitive treatment can also be carried out.

According to a preferred embodiment, the helix obtained during twisting extends over the entire length of the filament.

According to a preferred embodiment, the helix obtained during twisting extends only over part of the filament, and in particular the twisted region periodically interchanges with the untwisted region. In particular, in the case of an interdental cleaner, it is advantageous if the interdental cleaner is only twisted over a portion of its length. The untwisted area has a smaller cross sectional dimension and can therefore be introduced more easily into the space between the teeth. This insertion can be made easier if the untwisted portion has, for example, a cross-section flattened by compression, at least in part.

According to a preferred embodiment, the filament is wound on the reel after twisting. In this manner, additional steps of, for example, joining, cutting or subsequent processing are available.

A preferred post-treatment is heat treatment. Generally, the prior art includes filaments that are not optimally stabilized, so that the heat treatments presented below can also be considered unique, even without twisting. The extruded (and twisted and heat stabilized) filaments are drawn onto a reel and heated in a temperature control unit (e.g., hot air or steam temperature control unit or autoclave). The autoclave is particularly preferred as a temperature control unit and the filament is heated in a pressurized atmosphere with steam in the autoclave. The force acting on the filament on the reel is preferably 0.001 to 500 N, especially 0.01 to 5 N.

According to a preferred embodiment, the tensile stress of the filament on the reel is 0.1 to 1000 N / qmm (or up to 500 N / qmm only), especially 1 to 100 N / qmm.

According to a preferred embodiment, the inner chamber and the filament of the autoclave are heated to a predetermined starting temperature in the sealed inner chamber. After reaching the starting temperature in the inner chamber, a negative pressure is preferably generated and the first negative pressure state is maintained for a predetermined period of time. In the next step, steam is introduced into the inner chamber or created in the inner chamber, and the steaming temperature is higher than the starting temperature. The duration of the steam treatment is particularly longer than the first negative pressure period, and the steam treatment consists of an introduction step and a treatment step, preferably the two steps of the introduction step and the treatment step are longer than the first negative pressure period.

 It is advantageous to dry the filaments after completing the steam treatment. Also, preferably, the negative pressure is generated more than once, and the temperature is equal to or lower than the steam treatment step. The final negative pressure step is maintained over a second period of negative pressure, and the final negative pressure step is shorter than the processing step. The ambient pressure is then reproduced in the inner chamber and the treatment is terminated.

The starting temperature is preferably 40 캜 to 90 캜, particularly 50 캜 to 80 캜.

In particular, during the negative pressure stage the inner chamber is vacuum, and in most applications the vacuum is approximately vacuum, medium vacuum or high vacuum or ultra-high vacuum in some applications. The pressure of the inner chamber during the negative pressure stage is preferably less than 300 millibar (mbar), especially less than 1 millibar, and in some applications less than 0.001 millibar. For technical reasons, the lower limit for air pressure is preferably one mil- lion billionth.

The duration of the first negative pressure step is preferably not more than 5 minutes, in particular not more than 3 minutes. In particular, the lower limit of this period is one second.

The duration of the second negative pressure step is preferably not more than 30 minutes, in particular not more than 20 minutes. In particular, the lower limit of this period is 10 seconds. For the twisted filaments, the period is 1/2 to 1/5, preferably 3 to 8 minutes for the untwisted filaments.

The steam treatment includes an introduction step and a subsequent processing step in which steam is introduced into the inner chamber or formed in the inner chamber and heated to the steam treatment temperature and in the processing step the filament is subjected to a heat treatment .

The steam treatment temperature is preferably 20 ° C to 120 ° C higher than the starting temperature. In particular, steam treatment temperatures for twisted filaments and untwisted filaments are different, 120 占 폚 to 180 占 폚 for twisted filaments and preferably 80 占 폚 to 130 占 폚 for untwisted filaments. The duration of the introduction step is preferably 1 to 20 minutes, particularly 4 to 11 minutes. The duration of the treatment step is 10 to 110 minutes, in particular 5 to 120 minutes, longer than the introduction step. In particular, the treatment periods for the twisted filaments and the untwisted filaments are different, and the treatment period for the twisted filaments is 1.5 to 3 times longer than the treatment period for the untwisted filaments, and the treatment period for the untwisted filaments is Preferably 20 to 80 minutes. In particular, the duration of the treatment step in the twisted filament is preferably from 50 minutes to 200 minutes.

As an example, the heat treatment of the polyamides [NH- (CH 2) 6 -NH-CO- (CH 2) 4 -CO] n (also referred to as PA 6.6) of hexamethylenediamine and adipic acid is described below. , The twisted filament of PA 6.6 is wound 100 times, where the filament has a diameter of 1/10 mm, is placed in an autoclave, the inner chamber is closed and the starting temperature is set at 60 ° C. The first negative pressure The process takes place over a period of 30 seconds at a pressure of 300 millibar to 100 millibar and then the temperature of the inner chamber is increased to 130 DEG C over a period of 10 minutes and steam is introduced. , And when this is complete the second negative pressure step lasts for 7 minutes and the temperature is 70 DEG C. The ambient pressure is then restored to the inner chamber and the inner chamber is opened and the filament can be removed.

Similar heat treatments as described above can be used for non-spiral filaments made of PA 6.6, with a temperature of 90 DEG C being selected instead of a temperature of 130 DEG C and the treatment step lasting 35 minutes.

The filaments according to the present invention can be cut to form a hair that can be used for many kinds of brushes. For example, concave areas provided between the spirals on the surface when twisting non-circular monofilaments are particularly suitable for removing contaminants removed during brushing, retaining in recesses, and discharging contaminants at the end of brushing Do. Such advantageous effects are used, for example, in carpet brushes, vacuum cleaner brushes, polishing brushes and the like.

Examples of preferred embodiments of the device according to the present invention are shown in the figures.

Figure 1 shows the portion of the filament 2 around which the second filament part is wound around the central filament zone. This may be a central monofilament wrapped around a second monofilament or a single monofilament (or a strand of monofilament), the upper layer having a colored line or other material and being twisted along its longitudinal axis.

Figure 2 shows a preferred embodiment of the device according to the present invention. The untwisted filaments are unwound from the roller 1 after the filaments are wound and the filament 2 is unwound and travels over the illustrated heating rollers 3 only once during a number of possible rotations, And twisted. As shown by the arrows, the filaments 2 can be guided around the reel 4. However, it is also possible for the reel 4 to rotate in the direction opposite to the direction of the arrow shown.

Figures 3 and 4 respectively show cross sections of filaments comprising two different halves (shown in black and white). The filaments twisted so that the longitudinal axis projects from the plane of the image is shown as one body and the cross section shown is continuously rotated over the longitudinal axis. Figure 3 shows a filament that is continuously twisted to the core. In FIG. 4, only the zones lying outside are sufficiently heated so that the twisting does not extend into the core, or at least the outer layers are twisted further than the core.

It is to be understood that the embodiments are illustrative of possible modifications and that the present invention is not limited to the specific embodiments shown and that various combinations of the individual embodiments are possible and that such variations are also within the scope of the present invention, It should be noted that it belongs to the skill of

Moreover, individual features or combinations of features in the different embodiments shown and described may in themselves represent an independent solution according to the present invention. The problem solved by the unique solution according to the present invention can be known from the detailed description.

All details of the numerical ranges herein are intended to limit the numerical range to include any or all portions of the range. For example, a range of 50 캜 to 70 캜 may range from a lower limit of 50 캜 up to an upper limit of 70 캜 Quot; means that all ranges of " a " For the most part, individual embodiments can form what is the subject of an independent solution according to the present invention.

1: Rollers
2: filament
3: Heating roller
4: Reel

Claims (9)

An apparatus for manufacturing a spiral filament, comprising: an extrusion unit for extruding at least one monofilament; a twisting unit twisting at least one monofilament around its longitudinal axis under tensile stress; and a temperature control unit for heat treatment of the filament,
The extrusion unit is arranged to extrude at least one monofilament,
The twisting unit is arranged to twist at least one extruded monofilament around its longitudinal axis under tensile stress,
The temperature control unit is arranged to effect heat treatment of the filaments before twisting the at least one extruded monofilament, and / or during twisting and / or twisting, and at the same time being arranged to be stretched about its longitudinal axis, And the spiral filament is produced. The method according to claim 1,
Characterized in that the apparatus is configured such that a heat treatment is carried out at a specific time only, especially before or after twisting, or less than one second after twisting of the short portion of the filament, said short portion being less than 5 meters in particular Filament manufacturing apparatus. 3. The method according to claim 1 or 2,
The apparatus is configured such that the filament is guided through a heated fluid or guided over a heated surface before or after twisting, or after twisting, the temperature of the heated filament being greater than the glass of at least one material used in the filament Preferably 80% to 110% of the transition temperature, and the heated surface is preferably a straight section or a round section, in particular in the form of a roller. 4. The method according to any one of claims 1 to 3,
Wherein the heat source is an infrared radiator. 5. The method according to any one of claims 1 to 4,
Preferably, the temperature and duration of the heat treatment are such that the filament is not heated to its core, but less than 70% of the circumferential radius of the filament cross-section is between 80% and 110% of the glass transition temperature % ≪ / RTI > of the spiral filament. 6. The method according to any one of claims 1 to 5,
The apparatus is configured so that at least one monofilament is pre-drawn and especially further drawn out after extrusion and prior to twisting in an additional step, and in order to stabilize the at least one monofilament, the monofilament is preferably pre- Wherein the spiral filament is stabilized. 7. The method according to any one of claims 1 to 6,
Wherein the device is configured such that the spiral obtained during twisting only extends over a portion of the filament, and in particular the twisted area is periodically alternating with the untwisted zone. 8. The method according to any one of claims 1 to 7,
The apparatus comprises an additional temperature control unit, preferably an autoclave, configured to heat twisted and thermally stabilized filaments wound on the reels after thermal curing, preferably the tensile stress of the filaments in the reel is from 0.1 to 1000 N / Preferably, the temperature control unit heats the filament in a sealed inner chamber to a predetermined starting temperature, preferably forms a negative pressure after reaching the starting temperature in the inner chamber, and maintains the first negative pressure state for a predetermined period of time Wherein the steam treatment temperature is higher than the starting temperature and the steam treatment period consisting of the introduction step and the treatment step is carried out in a first negative pressure state, And the filament is dried after completing the steam treatment, Wherein the temperature is equal to or lower than the temperature during the steaming treatment and the final negative pressure stage is maintained over a period of the second negative pressure state and the final negative pressure stage is shorter than the processing stage. 9. A filament produced by the apparatus according to any one of claims 1 to 8, characterized in that the polymer chain of the filament is twisted at least on the outer surface of the filament, but no internal torsional stress is present in the filament.

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