JP2010222732A - Conjugate monofilament and method for producing the same - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a conjugate monofilament including a sheath material in which a functional component is compounded with a resin forming the sheath material, and exposed to the surface of the sheath material so that the activities such as degermination, deodorization, and antioxidation may be exhibited maximally, and to provide a method for producing the monofilament. <P>SOLUTION: The conjugate monofilament is produced by forming an undrawn core-sheath-type conjugate monofilament by co-extruding a first thermoplastic resin forming a core material X, and a second thermoplastic resin forming a sheath material Y, containing additive particles P and having the melting point lower than that of the first thermoplastic resin, and drawing the undrawn conjugate monofilament to expose the additive particles P compounded in the second thermoplastic resin to the surface of the sheath material Y. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

  The present invention is a core-sheath joint type having excellent functionality (deodorizing property, organic matter decomposability, etc.), spinnability, stretchability, and economical efficiency useful for various applications including filters for air conditioners and air purifiers. The present invention relates to a composite monofilament and a method for producing the same.

Conventionally, filters using composite monofilaments that are cost-effective and have excellent properties such as moldability, mechanical strength, water resistance, and chemical resistance have been widely used as filters incorporated in air conditioners and air purifiers. ing.
For example, Patent Document 1 discloses a polyolefin-based first resin, a polyolefin-based second resin in which a functional component such as catechins and a ceramic component are blended, the former being a core component and the latter being a sheath component. Thus, a core-sheath joint type composite filament composed of a core component and a sheath component is described.

Japanese Patent Laid-Open No. 2001-159029

However, in the composite filament of Patent Document 1, a functional component such as catechins and a ceramic component are kneaded inside the second resin serving as the sheath component, and cannot be exposed to the surface of the sheath material. There has been a demand for improvement in the effect of functional components such as catechins.
Then, an object of this invention is to provide the composite monofilament which exposed the coarse grain mix | blended with the sheath material on the surface of the sheath material.
Another object of the present invention is to add a functional component to a resin to be a sheath material so that the functions such as sterilization, deodorization, and antioxidant can be maximized. It is to provide a composite monofilament exposed on the surface and a method for producing the same.

(1) The composite monofilament of the present invention includes a first thermoplastic resin (R1) that forms the core material X and additive particles (P) that form the sheath material Y, and includes the first thermoplastic resin (R1). The second thermoplastic resin (R2) having a low melting point is co-extruded to form an unstretched core-sheath bonded composite monofilament, and the unstretched composite monofilament is stretched to obtain the second thermoplastic resin. The additive particles (P) blended in (R2) are exposed on the surface of the sheath material Y.
(2) The composite monofilament of the present invention is characterized in that, in (1), the additive particles (P) are metal particles (M) and / or ceramic particles (C).
(3) The composite monofilament of the present invention is characterized in that, in the above (1) or (2), the additive particles (P) are further fixed with fine particles (P1) on the surface thereof.
(4) The composite monofilament of the present invention is characterized in that, in (3), the fine particles (P1) are platinum nanoparticles.
(5) The method for producing a composite monofilament of the present invention includes the first thermoplastic resin (R1) that forms the core material X and the additive particles (P) that form the sheath material Y, and the first thermoplastic resin ( A second thermoplastic resin (R2) having a melting point lower than that of R1) is coextruded to form an unstretched core-sheath bonded composite monofilament, and the unstretched composite monofilament is stretched to obtain a second The additive particles (P) blended in the thermoplastic resin (R2) are exposed on the surface of the sheath material Y.

In the composite monofilament of the present invention, the core material X provides the necessary strength, and the sheath material Y provides functionalities such as deodorant properties, antimicrobial properties, and antioxidant properties.
In addition, since the coarse particles are exposed from the surface of the sheath material Y, the functional effect of the coarse particles is directly exhibited.
And since the fine metal particle (M) which exists in the sheath material Y is also adhering to the surface of the ceramic particle (C) of the additive particle (P), the deodorizing property, antimicrobial property, Excellent functionality such as oxidization is exhibited to the maximum.
In addition, even if it is used in contact with water or washed with water, the metal particles (M) and the ceramic particles (C) are not easily detached from the sheath material Y, so that their functionality lasts for a long time.
Further, the presence of the ceramic particles (C) contributes to improvement of the dimensional stability and heat resistance of the composite monofilament with respect to environmental changes such as temperature and humidity changes.
Furthermore, since the additive particles having functionality need only be blended in the sheath material Y, the addition amount of the additive particles can be greatly reduced, which is economically advantageous.

It is sectional drawing of the composite monofilament of this Embodiment. It is explanatory drawing which shows the state which made the fine particle (P1) adhere to the surface of an addition particle (P). It is a schematic explanatory drawing which shows the method of coextruding a sheath material and a core material and manufacturing an unstretched composite monofilament. It is explanatory drawing which shows the state which extended | stretched the unstretched composite monofilament and exposed the addition particle | grain on the surface of a sheath material.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a cross-sectional view of the composite monofilament of the present embodiment. FIG. 2 is an explanatory view showing a state in which fine particles (P1) are fixed to the surface of the additive particles (P). FIG. 3 is a schematic explanatory view showing a method for producing an unstretched composite monofilament by coextrusion molding of a sheath material and a core material. FIG. 4 is an explanatory view showing a state in which the unstretched composite monofilament is stretched to expose the additive particles on the surface of the sheath material.

<Composite monofilament>
As shown in FIG. 1, the composite monofilament of the present embodiment is a core-sheath joint type composite filament composed of a core material X and a sheath material Y, and was included in the second thermoplastic resin (R2). The additive particles (P) are exposed on the surface of the sheath material Y. The core-sheath bonded type monofilament may be a conventionally known core-sheath type, and may be any of a concentric circular core-sheath type, an eccentric core-sheath type, and a multi-core core-sheath type.

<Core X>
In the present invention, the core material X is formed of the first thermoplastic resin (R1), and is a resin that becomes soft when heated to the glass transition temperature or the melting point and can be molded into a desired shape. Examples of the thermoplastic resin include polyethylene, polypropylene, polyvinyl chloride, polyvinylidene chloride, polystyrene, polyvinyl acetate, Teflon (registered trademark), ABS resin, AS resin, acrylic resin, and the like in the present invention. Either can be used.

<Sheath material Y>
The sheath material Y is formed of the second thermoplastic resin (R2) blended with the additive particles (P), and the first heat constituting the core material X is an example of the second thermoplastic resin (R2). The same thing as a plastic resin (R1) can be used.

The polyethylene constituting the core material X and the sheath material Y is a polymer having the simplest structure in which ethylene is polymerized. High density polyethylene, low density polyethylene, ultra low density polyethylene, linear low density polyethylene, ultra high There are molecular weight polyethylenes, but any of them can be used. The polyethylene may be not only a homopolymer of ethylene but also a copolymer with an α-olefin such as propylene or butene-1 mainly composed of ethylene.
Polyethylene has a melt index (MI) of 0.1 to 100, preferably 0.2 to 80 in many cases. MI represents the mass of a sample extruded for 10 minutes under the conditions of a temperature of 190 ° C., a load of 2160 g, and an orifice hole diameter of 2.092 mm in g.

The polypropylene constituting the core material X and the sheath material Y is a polymer obtained by polymerizing propylene, and is not only a homopolymer of propylene but also a copolymer with an α-olefin such as ethylene and butene-1 mainly composed of propylene. It may be.
The melt flow rate (MFR) of polypropylene is 0.3 to 400, preferably 0.5 to 200.

A typical example of polypropylene is a propylene homopolymer having a melting point of, for example, 150 ° C. or more, and a composite filament having such a high melting point polypropylene as a core material X has spinnability, stretchability, physical properties (strength, dimensional stability). ) And the like.
In addition, melt flow rate (MFR) represents the mass of the sample extruded for 10 minutes on the conditions of temperature 230 degreeC, load 2160g, and orifice hole diameter 2.092mm in g number.

In the composite monofilament having the above-described configuration, it is preferable that the second thermoplastic resin (R2) serving as the sheath material Y is a thermoplastic resin having a lower melting point than the first thermoplastic resin (R1) serving as the core material X. For example, a resin having a melting point of 5 ° C. or higher, more preferably 30 ° C. or lower is used.
In addition, when it is set as the core material X and the sheath material Y by the same resin, it can be set as the core material X of high melting | fusing point by enlarging the average molecular weight of resin.

  The kind of the additive particles (P) to be blended in the sheath material Y is not particularly limited, and any particles that do not melt by heating during stretching may be used, and examples thereof include particles of resin, metal, glass, ceramics, and the like. . By adding the additive particles having the functionality, the sheath material Y can have the function.

  The metal particles (M) to be blended in the sheath material Y are not particularly limited, but platinum, gold, silver, copper, nickel, stainless steel, and the like are included, and the metal particles (M) have. The function can be imparted to the sheath material Y.

For example, although metal particles (M) such as platinum, gold, and silver have a photocatalytic function, they are expensive, so fine particles (P1) having an average particle diameter of about 1 to 5 nm are converted into ceramic particles. It can be used by adhering to the surface of (C).
In addition, by adhering to the surface of the ceramic particles (C), the sterilization action and deodorization over a long period of time without depleting or disappearing the metal particles (M) such as platinum, gold, and silver blended in the sheath material Y It is possible to bring about catalytic effects such as action and antioxidant action.

  As the ceramic particles (C) to be blended with the sheath material Y, various ceramics can be used, and those obtained by adding an inorganic material such as silica gel to the ceramic particles (C) can also be used.

  As silica gel, silica gel obtained through hydrous silicate gel is preferably used. At this time, an aqueous solution of silicate is mixed with an acid to adjust the pH to form a hydrous gel, and the hydrous gel is washed with water to remove ions and then dried to obtain silica gel.

In addition, there are inorganic materials as ceramic particles (C) to be blended with the sheath material Y. Examples of inorganic materials include polyvalent metal salts of inorganic acids such as phosphoric acid, sulfuric acid, nitric acid, and carbonic acid, alkali metals and alkaline earths ) Organosilica sols using an organic solvent such as a metal fluoride, silicofluoride, colloidal silica, or alcohol as a medium can be used.
Various clay minerals, oxides, hydroxides, composite oxides, nitrides, carbides, silicides, borides, zeolites, cristobalite, diatomaceous earth, polyvalent metal salts of silicic acid, and the like can also be used. .
Examples of clay minerals include kaolin, wax, sericite, and bentonite.
Examples of the oxide include alumina, titania, silica, zirconia, and magnesia.
Examples of the hydroxide include aluminum, zinc, magnesium, calcium, manganese hydroxide, and the like.
Examples of the composite oxide include alum, examples of the nitride include silicon nitride and boron nitride, and examples of the carbide include silicon carbide and boron carbide.
Examples of the polyvalent metal salt of silicic acid include aluminum salts, zinc salts, magnesium salts, calcium salts, and manganese salts.

  As described above, the sheath material Y is formed of the second thermoplastic resin (R2) in which the additive particles (P) are blended. When a plurality of types of additive particles (P) are blended, they can be blended in the second thermoplastic resin (R2), respectively, but composite particles in which a plurality of types of additive particles (P) are mixed in advance are manufactured, and the composite It is preferable to blend the body particles with the second thermoplastic resin (R2) from the viewpoint of uniform dispersion of the plural additive particles.

The ratio of the second thermoplastic resin (R2) and the additive particles (P) in the sheath material Y is 1 to 50 masses of the additive particles (P) with respect to 100 parts by mass of the second thermoplastic resin (R2). It is desirable to be a part. Preferably it is 2-30 mass parts.
As for the ratio in the case where the additive particles (P) are composed of the metal particles (M), the ceramic particles (C) and other additive particles, it is desirable that the total amount thereof is within the above range.
When the amount of the additive particles is too small, the desired deodorant properties, antimicrobial properties, physiological activity, antioxidant properties, etc. are not fully exhibited, while the latter amount is too large. However, not only does the functionality not exceed a certain level, but also the negative aspects of the reduction of the productivity of the composite monofilament and the reduction of the strength and texture become conspicuous.

When the additive particle (P) is composed of the metal particle (M) and the ceramic particle (C), the ceramic particle (C) 100 mass in the relationship between the metal particle (M) and the ceramic particle (C). It is desirable that the metal particles (M) be 0.1 to 10 parts by mass with respect to parts. Preferably it is 0.1-5 mass parts, More preferably, it is 0.2-1 mass part.
When the proportion of the metal particles (M) is too small, the desired deodorizing properties, antimicrobial properties, physiological activity, antioxidant properties and the like are insufficient, and when the proportion of the metal particles (M) is too large, the ceramic particles ( The balance with respect to C) is lost, which is disadvantageous in terms of cost.
As shown in FIG. 2, when fine particles are used as the metal particles (M), the metal particles that are fine particles and the ceramic particles that are large particles are mixed, for example, heated and sintered to obtain ceramic particles. In this case, the metal particles (M) of the fine particles are not buried in the second thermoplastic resin (R2), which is the sheath material Y, by pre-manufacturing the fine particles fixed on the surface of the sheath. It can be exposed on the surface of the material Y.

<Ratio of core material X and sheath material Y>
The ratio of the core material X and the sheath material Y in the composite monofilament is, by mass ratio, the core material X: the sheath material Y = 30: 70 to 80:20, preferably 35:65 to 75:25. When the ratio of the sheath material Y is small, the ratio of the added particles (P) becomes too small, so that the expected functionality is not sufficiently achieved, and the added particles (P) cannot be retained. On the other hand, when the ratio of the sheath material Y is large, the additive particles (P) are buried in the sheath material Y after being stretched and are not exposed on the surface of the sheath material Y.

<Production method of composite monofilament>
As shown in FIG. 3, the composite monofilament of the present embodiment includes a first thermoplastic resin (R1) and a second thermoplastic resin (R2) containing additive particles (P). Manufactured by coextrusion molding at a temperature equal to or higher than each melting temperature so that (R1) is the core material X and the second thermoplastic resin (R2) containing the additive particles (P) is the sheath material Y. be able to. Co-extrusion can be achieved by using two extruders and discharging downward from the composite die F in a concentric line.
On the second thermoplastic resin (R2) side, a master batch having a high concentration of the internally added material is prepared in advance, and the master batch is mixed with the second thermoplastic resin (R2) for molding. You can also.

For the first thermoplastic resin (R1) and the second thermoplastic resin (R2), an antioxidant, an ultraviolet absorber, a colorant, a lubricant, an antistatic agent, a matting agent, a fluidity improver, a plastic, if necessary. Auxiliaries, flame retardants and other auxiliaries can also be added. In particular, the second thermoplastic resin (R2) containing a plurality of types of additive particles (P) is effective in improving anti-aggregation properties and dispersibility, including metal soap, together with a stabilizer such as an antioxidant. It is preferable to blend a molding aid together to ensure uniform dispersion of the additive particles (P).
In addition, when the metal particles (M) are blended, in order to improve the supportability, copper salt, iron salt, calcium salt, titanium salt, aluminum salt, silver salt, tin salt, zinc salt, chromium salt, cobalt An appropriate amount of a metal ion source such as a salt can be allowed to coexist.

  As shown in FIG. 4, the unstretched composite monofilament produced by coextrusion is stretched by a subsequent stretching process to reduce the thickness of the sheath Y, thereby adding particles (P) blended in the sheath Y. Is exposed on the surface of sheath Y. At this time, when the melting point of the second thermoplastic resin (R2) constituting the sheath Y is lower than the melting point of the first thermoplastic resin (R1) constituting the core material X, the sheath Y is further stretched. The thickness of the sheath Y becomes thin, and the additive particles (P) blended in the sheath Y are exposed on the surface of the sheath Y. In addition, the thickness of the sheath Y after stretching is not particularly specified, but it is desirable to make it smaller than the average particle diameter of the additive particles (P).

  Although there is no particular limitation on the stretching ratio, when the ratio is too small, the ratio of exposing the additive particles (P) blended in the second thermoplastic resin (R2) to the surface of the sheath material Y is insufficient. The magnification is desirably 5 times or more. On the other hand, if the stretch ratio is too large, troubles such as easy delamination at the core-sheath joint interface may occur. Therefore, the upper limit of the stretch ratio is generally preferably about 10 times. The stretching temperature is desirably higher than the softening temperature of the second thermoplastic resin (R2) constituting the sheath Y.

<Application, application>
The composite monofilament of the present embodiment can have any thickness from very fine denier to very thick denier. Moreover, secondary products, such as a net | network, a rope, a belt, a thread | yarn, a pile, cotton (cotton) shape, a woven fabric, a nonwoven fabric, a knitted fabric, can also be obtained using a composite monofilament.
Furthermore, this composite monofilament and its secondary products are made from natural fibers (cotton, hemp, silk, wool, etc.), synthetic resins (polyester, acrylic, polypropylene, polyethylene, nylon, vinylon, polyvinylidene chloride, polyvinyl chloride, polyurethane, etc.) ) Fiber, monofilament, semi-synthetic fiber (acetate, etc.), recycled fiber (rayon, etc.), inorganic fiber (metal fiber, glass fiber, carbon fiber, etc.), monofilament or their secondary products it can.

  Examples of uses of the composite monofilament or its secondary product of the present embodiment include filters (filters for air conditioners, air cleaners, vacuum cleaners, etc.), interior materials (wall sheets, floor materials, etc.), rug materials (mats) , Carpets, etc.), automotive interior materials (seat cloth, ceiling materials, flooring materials), footwear materials, industrial materials, clothing materials, bedding, hygiene materials, medical supplies, daily necessities, kitchenware, toiletries, packaging materials, etc. .

  Moreover, the composite monofilament of this embodiment can be made into a material having an extremely efficient photocatalytic function by blending titanium oxide or metal particles effective as a photocatalyst and exposing them to the surface of the sheath material Y. .

  Next, the present invention will be described in more detail with reference to examples.

<Example 1>
As the first thermoplastic resin (R1) to be the core material X, polypropylene (PP) having a melting point of 163 ° C. and an MFR of 3.1 was prepared. As the second thermoplastic resin (R2) to be the sheath material Y, polypropylene (PP) having a melting point of 128 ° C. and an MFR of 17.3 was prepared.
Dry mixing of the second thermoplastic resin (R2) with 130 parts of copper powder with an average particle diameter of 1 μm as metal particles (M) and 400 parts of silica particles with an average particle diameter of 325 mesh under as ceramic particles (C) And then blended.
By two extruders equipped with a composite die, coextruded at 205 ° C. for the sheath material Y and 230 ° C. for the core material X, and then stretched about 6 times at a stretching temperature of 230 ° C. A denier composite monofilament was obtained. The core material at this time was 200 denier.

<Example 2>
As the first thermoplastic resin (R1) to be the core material X, polypropylene (PP) having a melting point of 163 ° C. and an MFR of 5.9 was prepared. As the second thermoplastic resin (R2) to be the sheath material Y, high density polyethylene (HDPE) having an MI of 16.1 was prepared. 10 parts by mass of additive particles (P) were blended with the second thermoplastic resin (R2). The additive particles were produced as follows. That is, about 900 sheets having a thickness of about 1 to 2 mm are obtained by adding silica particles having an average particle diameter of about 1 μm to a mixture of colloidal silica and platinum particle colloid (average particle diameter of about 5 nm). Sintering was performed at ˜1000 ° C., and the platinum particles were fixed to the surface of the silica particles.
The method for producing the composite monofilament was the same as in Example 1.

  In the composite monofilament of the present invention, necessary strength is obtained by the core material X, and functionalities such as deodorizing property, antimicrobial property, and antioxidant property are obtained by the sheath material Y, and from the surface of the sheath material Y Since the coarse particles are exposed, the functional effects of the coarse particles are directly exhibited, and can be applied to filters, masks, wall materials, etc., and the industrial applicability is extremely high.

C Ceramic particle F Composite die M Metal particle P Additive particle X Core material Y Sheath material

Claims (5)

A first thermoplastic resin (R1) that forms the core material X;
A second thermoplastic resin (R2) containing additive particles (P) forming the sheath material Y and having a lower melting point than the first thermoplastic resin (R1),
Co-extrusion to form an unstretched core-sheath-bonded composite monofilament,
Stretching the unstretched composite monofilament,
The additive particles (P) blended in the second thermoplastic resin (R2)
A composite monofilament which is exposed on the surface of the sheath material Y. The additive particles (P) are
The composite monofilament according to claim 1, wherein the composite monofilament is metal particles and / or ceramic particles. The additive particles (P) are
Furthermore, the fine particle (P1) has adhered to the surface, The composite monofilament of Claim 1 or 2 characterized by the above-mentioned. The composite monofilament according to claim 3, wherein the fine particles (P1) are platinum nanoparticles. A first thermoplastic resin (R1) that forms the core material X;
A second thermoplastic resin (R2) containing additive particles (P) forming the sheath material Y and having a lower melting point than the first thermoplastic resin (R1),
Co-extrusion to form an unstretched core-sheath-bonded composite monofilament,
Stretching the unstretched composite monofilament,
The additive particles (P) blended in the second thermoplastic resin (R2)
A method for producing a composite monofilament, wherein the surface of the sheath material Y is exposed.

Images