KR101274444B1 - Functional pet fiber and manufacturing method thereof - Google Patents

Abstract

PURPOSE: A functional PET(poly(ethyleneterephthalate)) fiber is provided to emit far-infrared rays and anions, and to ensure antibacterial, disinfecting, deodorizing, heat insulation, and quick-drying properties. CONSTITUTION: A method for fabricating a functional PET fiber comprises: a step of synthesizing BHET(bis-2-hydroxy ethyl terephthalate) by transesterification of DMT(dimethyl terephthalate) and EG(ethylene glycol)(S10); a step of synthesizing a functional polyurethane prepolymer containing one or more functional ingredients among mud, scoria, silicon dioxide(SiO_2), magnesium(MgO), and antimony tin-oxide(ATO)(S20); a step of binding a functional group of the functional polyurethane prepolymer to a functional group of BHET(S30); and a step of polymerizing the functional polyurethane prepolymer-conjugated BHET, synthesizing PET resin containing the functional ingredient, and melt-spinning(S40,S50). The functional polyurethane prepolymer is prepared by dispersing powder of the functional ingredient to the polyurethane prepolymer. [Reference numerals] (S10) Synthesize BHET by transesterification of DMT and EG; (S20) Synthesize a functional polyurethane prepolymer in which functional powder is dispersed; (S30) Bind the BHET and the functional polyurethane prepolymer; (S40) Synthesize a functional PET resin by the polymerization of the BHET; (S50) Fiberize by the melt-spinning of the functional PET resin

Description

Functional PET fiber and manufacturing method {Functional PET fiber and Manufacturing method}

The present invention relates to a functional PET fiber and a method for manufacturing the same, and more particularly, a functional component that imparts functionality such as antibacterial, sterilization, deodorization, heat insulation, and the like to the fiber is uniform in the oligomer of the PET resin which is the basic material of the polymer yarn. It is configured to be firmly and firmly bonded, thereby minimizing the loss of the functional component by desorption even after the spinning process of the PET resin, and maximizing the uniformity of the functional component distributed inside the spun fiber, so that the function of the functional ingredient beneficial to the human body is properly expressed for a long time. The present invention relates to a functional PET fiber and a method of manufacturing the same.

Generally, fibers used for fabricating clothes are broadly classified into natural fibers and synthetic fibers. Of these synthetic fibers, synthetic fibers synthesized from low molecular weight compounds and polymerized by chemical methods are used as synthetic fibers And a representative example thereof is PET (polyethylene terephthalate) fiber, which is a kind of polyester fiber.

Since the PET fiber has various excellent physical properties and advantages, it is widely used for the production of coatings instead of natural fibers. However, bacterial or microorganisms are easily propagated by organic substances such as fat or protein contained in perspiration secreted from the human body There is a problem that a malodor is generated or a skin disease is caused in a contacted body.

Recently, in order to solve such a problem, a method of directly spinning a yarn by directly mixing powders of a functional material such as yellow soil or silver into a molten PET resin has been mainly used. In the yarn spinning technique Is described in detail in [1] below and the like in detail.

However, in the yarn spinning method disclosed in the following [Document 1], the functional powder does not uniformly disperse in the polyester melt and is easily agglomerated, causing the trimming in the spinning process or the functionality of the spun fiber is not properly expressed. There was this.

In addition, in the case of the yarn spinning method disclosed in the following [Document 1], even if the spinning is properly made, since the bonding strength between the functional particles and the PET resin constituting the yarn is weak, the functional component is easily detached by repeated washing process There was a problem that the functionality does not last.

[Patent Document 1] Korean Registered Patent No. 715334 (disclosed on Apr. 28, 2006)

The present invention is to solve the problems of the prior art as described above, an object of the present invention is to ensure that the functional component of the fiber in the PET resin which is the base material of the yarn is firmly bonded to the PET resin polymer by a polymer ligand binder Even after spinning the yarn using the PET resin, the functional component beneficial to the human body can be properly expressed for a long time by minimizing the loss of the functional component by desorption and maximizing the uniformity of the functional component distributed inside the spun fiber. It is to provide a functional PET fiber and a method for producing the same.

In order to achieve the above object, a method for producing a functional PET fiber according to the present invention is a compound for synthesizing BHET (bis-2-hydroxy ethyl terephthalate) by transesterification of dimethyl terephthalate (DMT) and ethylene glycol (EG). 1st step, mud (scoria), silicon dioxide (SiO ₂ ), aluminum oxide (Al ₂ O ₃ ), magnesium oxide (MgO), antimony tin oxide (ATO) at least any one of the functional components included A second step of synthesizing the functional polyurethane prepolymer, a third step of bonding the functional group of the functional polyurethane prepolymer synthesized in the second step to the functional group of the BHET synthesized in the first step, and the functional polyurethane prepolymer And a fourth step of polymerizing the bonded BHET to synthesize the PET resin including the functional component, and melt spinning the fiber to form the PET resin. It is characterized by being obtained by dispersing the powder of the functional ingredient in a retan prepolymer.

In addition, the second step, by stirring a polyol (polyol), dimethylol propionic acid (DMPA; Dimethylol Propionic Acid), and N-methyl-2-pyrrolidone (NMP; N-methyl-2-pyrrolidone) Dibutyltin dilaurate (DBTDL; dibutyl tin dilaurate) and an isocyanate compound are added dropwise to the mixture of step 2-1 and step 2-1, followed by stirring to prepare a polyurethane prepolymer having an -NCO group as an end group. Step 2-2 of synthesizing, mixing triethylamine (TEA) in the polyurethane prepolymer and then stirring to neutralize by step 2-3, and the powder of the functional ingredient is added to the polyurethane prepolymer is completed neutralization Characterized in that it comprises a 2-4 step of dispersing.

Also, the polyol is propylene glycol (PPG), and the isocyanate compound is isophorone diisocyanate (IPDI).

Further, in the third step, the binding of BHET and the functional polyurethane prepolymer is characterized by a synthesis reaction of an -OH group which is an end group of BHET and an -NCO group which is an end group of a polyurethane prepolymer.

As described above, the functional PET fibers according to the present invention are inorganic compounds such as mud, volcanic stone and silicon dioxide having functions of far infrared radiation, anion radiation, heat insulation, insulation, and metal oxides such as aluminum oxide, magnesium oxide, and antimony tin oxide. Because it is added as a functional ingredient of the nano-powder, the fiber fabric has the advantage of exhibiting the functionality of far-infrared and anion radiation, antibacterial, sterilization, deodorization, heat insulation, fast drying.

In addition, since the functional PET fiber according to the present invention is manufactured in such a way that the functional component to be added is firmly bonded to the PET resin which is the base material of the yarn by the polymer ligand binder, the powder of the functional component is directly mixed into the melt of the PET resin. Compared with the prior art, there is an advantage that it is possible to minimize the loss of the functional component due to washing of the fiber.

In addition, since the functional PET fiber according to the present invention is a method in which the functional component is added to the polymer ligand binder in the form of a dispersion having excellent dispersibility, the uniformity of the distributed functional component inside the PET fiber is significantly improved as compared with the conventional technology. There is an advantage that can maximize the functionality of the above-described fiber fabric.

1 is a process chart showing a method for producing a functional PET fiber according to the present invention,
Figure 2 is a process chart showing a method for producing a polyurethane prepolymer dispersed in a functional powder used in the production of functional PET fibers according to the present invention, and
Figure 3 is a view for explaining the configuration of the yarn for weaving functional PET fibers according to the present invention.

Hereinafter, with reference to the accompanying drawings, preferred embodiments of the present invention will be described in detail.

1 is a process chart showing a method for producing a functional PET fiber according to the present invention, Figure 2 is a process chart showing a method for producing a polyurethane prepolymer dispersed in a functional powder used in the production of a functional PET fiber according to the present invention, 3 is a view for explaining the configuration of the yarn for weaving a functional PET fiber according to the present invention.

Method for producing a functional PET fiber according to the present invention is a first step of synthesizing bis-2-hydroxy ethyl terephthalate (BHET) which is a polymer of a polymer resin by reacting dimethyl terephthalate (DMT) and ethylene glycol (EG) A second step of synthesizing the dispersed functional polyurethane prepolymer (PU prepolymer), a third step of bonding the functional polyurethane prepolymer to the synthesized BHET, the BHET to which the functional polyurethane prepolymer is bonded to a functional PET resin It comprises a fourth step of synthesizing, and a fifth step of spinning the yarn of the functional PET fiber using the functional PET resin, will be described in detail step by step below.

(Step 1) BHET  Synthesis step ( S10  step)

In general, the method of obtaining PET resin is TPA method for synthesizing PET resin by esterification reaction of terephthalic acid (TPA) and EG, and BHET for low polymer by transesterification reaction between DMT and EG. And DMT method in which PET resin is synthesized by polymerization.

Of these, the TPA method requires that the chemical equivalents of TPA and EG be maintained at exactly 1: 1 to synthesize a polymer having a high degree of polymerization, and it is not easy to obtain pure TPA. Thus, in this embodiment, Synthesis method was used.

To this end, in the first step of the manufacturing method of the functional PET fiber according to the present invention, first, DMT and EG, which are raw materials used for the synthesis of PET resin, are reacted (specifically, transesterification reaction) to synthesize the oligomer BHET first. The reaction scheme is expressed as [Scheme 1] below.

[Reaction Scheme 1]

At this time, the reaction according to the above-mentioned Reaction Scheme 1 is performed at 190 to 220 ° C in a nitrogen atmosphere at atmospheric pressure. As the catalyst, Li, Ca, Mg, Mn, Zn or Pb acetate can be used.

(Step 2) Functional polyurethane Prepolymer  Synthesis step ( S20  step)

When BHET is synthesized as described above, in the present invention, a functional component is added to the BHET before the PET resin is synthesized by a polymerization process. In this embodiment, the functional component includes mud, scoria, At least one of an inorganic compound such as silicon dioxide (SiO ₂ ) and a metal oxide such as aluminum oxide (Al ₂ O ₃ ), magnesium oxide (MgO) and antimony tin oxide (ATO) ) Is added in the form of.

The mud is usually formed by deposits of mud-clay loose materials, decomposition products of plants and animals, soil, salts and so on, which have been subjected to geological and chemical action for a long time and are decomposed by microorganisms. The mud is formed of silica, alumina, Potassium, sodium oxide and the like, and the specific composition thereof is shown in [Table 1] and [Table 2] below.

In addition, mud in the entire specification of the present invention means generally referred to as mud (mud) having the components of the following [Table 1] and [Table 2], in this embodiment mud added to PET fibers Bordeaux mud powder was used as an example as a powder.

Mud content (%) ingredient Al ₂ O ₃ CaO Fe ₂ O ₃ K ₂ O MgO MnO Na ₂ O TiO ₂ SiO ₂ P ₂ O ₅ content 15.1 0.72 3.73 2.83 1.58 0.04 2.43 0.62 68.4 0.08

Elemental content per mud sample (%) Si Al Fe Ca Mg K Na Boryeong Mud 32.3 9.75 2.91 1.01 0.92 2.38 1.88 Pohang Mud 34.4 6.12 2.40 1.14 0.64 1.24 0.48 Israel Dead Sea 22.1 4.49 2.18 9.74 3.10 1.45 1.80 Baikal, Russia 30.2 5.35 2.93 17.10 7.96 1.01 1.69

The mud constituted in this way is known to contain a large amount of natural minerals, germanium, bentonite, etc., and has an excellent effect on skin beauty such as skin aging prevention action, skin cleansing action, and skin wastes removal action.

In addition, since the mud has a sterilizing and antibacterial effect, it has an anti-inflammatory effect and skin immunity when it is in contact with the skin. In the case of germanium contained in the mud, there is also an effect of radiating far infrared ray which is beneficial to the human body.

The volcanic stone is a mass of rock with a large number of air holes and a diameter of 4 mm or more among the volcanic eruptions, and has a color such as black, brown, and red, and emits far-infrared rays and anions which are beneficial to the human body.

At this time, the far-infrared rays penetrate into the living body and cause self-heating, resulting in a warming effect and a sweating effect. As a result, microvessel expansion, blood circulation promotion, tissue activation, promotion of metabolism, waste products and harmful metals are discharged .

In addition, when the anion is absorbed into the human body, it exhibits the effect of promoting cell metabolism, nervous stability, fatigue recovery, appetite enhancement, and neutralizing cations of other substances causing antibacterial, sterilization, and odor to remove odor have.

In addition, since silicon dioxide (silica) has the characteristic of emitting far infrared ray and anion which are beneficial for human body as described above, it gives a function of far-infrared ray irradiation, antibacterial, sterilization, deodorization and the like, Thereby providing a function of improving thermal insulation.

In addition, the aluminum oxide (alumina) has a characteristic of radiating far-infrared rays and anion which are beneficial to the human body like silicon dioxide, so that the fibers are imparted with far infrared ray radiation, antibacterial, sterilizing and deodorizing functions, Thereby imparting a function of improving heat insulating property and insulating property of the fiber.

In addition, since magnesium oxide has a characteristic of emitting far infrared ray and anion which are beneficial to the human body, it imparts functions of far-infrared radiation, antibacterial, sterilization, and deodorization to the fibers. The heat insulation and flame- And the like.

On the other hand, the antimony tin oxide can further improve the functionality of the fiber by imparting functions such as electromagnetic shielding and ultraviolet shielding to the fiber.

Therefore, the present invention is characterized in that the far-infrared rays and anions that are beneficial to the human body are radiated from the fiber fabric itself by binding the functional ingredients having such beneficial effects to the fiber in direct contact with the skin.

In addition, in the present invention by combining such functional components to the fiber to ensure that the fiber fabric has functions such as antibacterial, sterilization, deodorization and the like to prevent the growth and odor of microorganisms generated in the fibers constituting the garment by the secretion of the human body and It is characterized by preventing the occurrence of skin diseases in advance.

In addition, the present invention is characterized by maximizing the functionality of the fiber by combining the functional components such that the fiber fabric further has functions such as thermal insulation, insulation, flame retardant, electromagnetic shielding, ultraviolet shielding.

To this end, in the present invention, a polyurethane (PU) prepolymer prepared by dispersing the functional component in the form of a dispersion is synthesized and bound to the BHET, whereby the functional component is firmly bonded to the BHET To be combined with each other.

The functional PET fiber according to the present invention by such a configuration is repeated even after the fiberization is made by maintaining the state in which the functional component is firmly bonded to the PET resin even when the PET resin is obtained by polymerizing the BHET as described below Due to this, there is an advantage that the functional component can be significantly prevented from being easily detached from the fiber.

In addition, the functional PET fiber according to the present invention is bonded to the BHET in the form of a dispersion (dispersion) excellent in the uniform dispersion force, the functional component bound to the fiber is uniformly distributed as a whole, the efficacy of the functional component described above There is an advantage that it can be effectively delivered to the entire skin wearing this fiber.

10 to 20 parts by weight of a polyol, 10 to 20 parts by weight of dimethylolpropionic acid (DMPA), and 10 to 20 parts by weight of a polyol are added to a reactor (for example, a four-necked flask) And 20 to 50 parts by weight of N-methyl-2-pyrrolidone (NMP). Subsequently, the mixture is purged with nitrogen and stirred at 60 ° C for 2 hours.

At this time, the polyol is a material obtained by reacting an initiator such as polyfunctional alcohol or aromatic amine having two or more hydroxyl groups (-OH) or amine groups (-NH ₂ ) in the molecule with propylene oxide or ethylene oxide under appropriate conditions, In this embodiment, propylene glycol (PPG), which is an ester-based polyol, is used as an example of the polyol material in order to improve the bondability with PET in the future.

In addition, the NMP is used as a solvent for dissolving DMPA, and also serves to lower the viscosity of a polyurethane prepolymer to be synthesized later.

Next, 0.01 to 10 parts by weight of dibutyltin dilaurate (DBTDL) as a tin (Sn) -based catalyst as a polyurethane reaction catalyst and 10 to 60 parts by weight of an isocyanate compound are slowly added dropwise to the reactor, For 4 hours to synthesize a polyurethane (PU) prepolymer having an -NCO group at the terminal group.

At this time, the isocyanate compound is preferably isophorone diisocyanate (IPDI) as a diisocyanate.

The content of -NCO groups in the synthesized polyurethane prepolymer was measured by a dibutylamine back-titration (DBBT) method. When the amount of the theoretical residual -NCO group was reacted with all the -OH groups .

After the synthesis of the polyurethane prepolymer having the -NCO end group was completed, the temperature of the reactor was lowered to 35 to 40 DEG C, about 0.01 to 3 parts by weight of triethylamine (TEA) was added as a neutralizing agent, and the mixture was stirred at about 300 rpm The carboxyl group (COOH group) group of the dimethylolpropionic acid (DMPA) is neutralized.

After the neutralization is completed, 0.01 to 20 parts by weight of a functional powder (preferably, nanoparticles having a particle size of 2 to 300 nm) of 1500 mesh or more is further added to finally synthesize a functional polyurethane prepolymer in which the functional powder is dispersed.

At this time, a dispersant or a diluent may be further added if necessary in order to uniformly disperse the functional powder in the polyurethane prepolymer.

When the functional powder is dispersed in the polyurethane prepolymer as described above, the protective effect of the hydrophilic colloid particles encircling the polyurethane prepolymer particles as the hydrophilic particles around the surface of the functional powder particles as the hydrophobic particles is generated. As a result, When the functional group (-NCO group) of the polyurethane prepolymer and the functional group of the BHET (-OH group) are firmly bonded to each other, the particles of the functional powder are also firmly bonded to the BHET while being surrounded by the polyurethane prepolymer particles .

(Step 3): Functional polyurethane Prepolymer and BHET ( S30  step)

When the first and second steps are completed, the polyurethane prepolymer dispersed in the functional powder synthesized in the second step is mixed with BHET, which is a low polymer of the PET resin synthesized in the first step, By the synthesis reaction, the -NCO group of the polyurethane prepolymer and the -OH group of the EG end group of BHET are firmly bonded to each other.

At this time, the mixing ratio of the BHET and the polyurethane prepolymer dispersed in the functional powder is preferably about 80 to 100 parts by weight of BHET and about 5 to 15 parts by weight of a polyurethane prepolymer. For the synthesis reaction, For 5 to 10 hours at about 100 to 300 rpm.

Meanwhile, in the present embodiment, the case where a functional polyurethane prepolymer is synthesized after synthesizing BHET is described as an example. However, the first and second steps may be performed independently of each other or may be performed in a different order, In the entire claims, the first and second steps may be performed independently of each other or may be performed in a different order.

(Step 4): A solution containing the functional ingredient PET  Synthesis of Resin ( S40  step)

As such, when the bonding of the polyurethane prepolymer in which the functional powder is dispersed in the low polymer BHET is completed, the PET resin containing the functional component is synthesized by a conventional polymerization reaction. The polymerization process is performed under vacuum pressure at 275 to 285 ° C. It is made by heating with a catalyst, Sb, Zn or Pb acetate or an oxide such as Sb, Ge, Pb can be used.

The above polymerization process can be represented by the following Reaction Scheme 2, and the above polymerization process must be performed until EG is completely removed to obtain a PET having a high molecular weight.

Also, the polyurethane prepolymer bonded to the BHET by the polymerization process is also polymerized with the polyurethane while maintaining the bonding state. In this case, the polymerized polyurethane functions as a functional polymeric ligand binder that binds the functional component to the PET.

[Reaction Scheme 2]

(Step 5): Yarn spinning and fiberizing step ( S50  step)

When a PET resin containing a functional component is obtained by the above-described method, the PET resin is melt-spinned and fibrousized. The melt spinning step may be performed by a conventional method known in the art.

Meanwhile, in the present embodiment, as an example, a case where the functional PET fiber according to the present invention is directly melt-spun PET resin containing the functional component synthesized in the fourth step is described as an example, but is not limited thereto. A master batch may be generated using the PET resin synthesized as described above, and a fiberization process by melt spinning may be performed using the master batch.

In this case, the master batch is produced by extruding or extruding the PET resin obtained in the fourth step by a known method, cooling the master batch, cutting the master batch into a predetermined size, and making the master batch Or the master batch is melted with a general PET resin (or a PET resin chip) to perform a yarn spinning process.

Functional PET fiber according to the present invention prepared in the manner described above is an inorganic compound, such as mud, volcanic stone, silicon dioxide, such as mud, volcanic stone, silicon dioxide having functions of far-infrared radiation, anion radiation, heat insulation, insulation and the like, aluminum oxide, magnesium oxide, antimony tin oxide Since the metal oxide such as is added as a functional component of the nano-powder, the fiber fabric has the advantage of exhibiting the functionality of far-infrared radiation, anion radiation, antibacterial, sterilization, deodorization, heat insulation, fast drying.

In addition, since the functional PET fiber according to the present invention is manufactured in such a manner that the functional component is firmly bonded to the PET resin by adding the functional component in the form of a polymer ligand bind before the synthesis of the PET resin which is the basic material of the yarn, Compared with the prior art in which the powder of the functional ingredient is mixed in the melt of the PET resin, there is an advantage that the loss of the functional ingredient due to washing of the fiber can be minimized.

In addition, since the functional PET fiber according to the present invention is a method in which the functional component is added in the form of a dispersion having excellent dispersibility, the uniformity of the distributed functional component inside the PET fiber is remarkably improved as compared with the prior art. The advantage is that it can be maximized.

Next, the characteristic structure of the yarn for weaving the fabric of the functional PET fiber according to the present invention will be described in detail with reference to FIG.

First, as shown in FIG. 3, the yarn 1 of the functional PET fiber containing the above-described functional component is first yarn 10 spun to extend in the longitudinal direction, and then spun to extend in the longitudinal direction. It comprises a second yarn 20 wound around the outer surface of the first yarn 10 in the longitudinal direction of the first yarn (10).

At this time, at least one of the first yarn 10 and the second yarn 20 is a yarn that melt-spun PET resin containing the above-described functional components, the second yarn 20 is the first yarn 10 ) Is wound so as to be spaced apart from the outer surface of the first yarn 10 at a predetermined interval so that the hollow layer 30 can be formed between the outer surface.

Functional yarn (1) containing a functional component according to the present invention by the configuration as described above to the outside through the hollow layer 30 that the cold air or heat supplied from the outside has the yarn itself as shown in FIG. Since it is an easily discharged configuration, there is an advantage that an excellent temperature maintenance effect can be obtained in summer or winter.

At this time, the first yarn 10 may be composed of a spanner made of polyurethane material having excellent elasticity as an example, the second yarn 20 is a DTY (draw textured yarn) PET yarn (functional component according to the present invention is It is preferably composed of PET yarn included).

In this embodiment, for convenience of description, a case in which the second yarn 20 of the first yarn 10 and the second yarn 20 is made of a PET yarn containing a functional component will be described as an example, but is not limited thereto. If necessary, both the first yarn 10 or the first yarn 10 and the second yarn 20 may be PET yarns containing a functional component.

Claims (5)

A first step of synthesizing BHET (bis-2-hydroxy ethyl terephthalate) by transesterification of dimethyl terephthalate (DMT) and ethylene glycol (EG);
Wherein at least one of functional groups of at least one of mud, scoria, silicon dioxide (SiO ₂ ), aluminum oxide (Al ₂ O ₃ ), magnesium oxide (MgO) and antimony tin oxide (ATO) A second step of synthesizing a urethane prepolymer;
A third step of binding the functional group of the functional polyurethane prepolymer synthesized in the second step to the functional group of BHET synthesized in the first step; And
Comprising a fourth step of synthesizing the PET resin containing the functional component by polymerizing the BHET to which the functional polyurethane prepolymer is bonded and melt spinning it to fiberize,
The functional polyurethane prepolymer is obtained by dispersing the powder of the functional ingredient in a polyurethane prepolymer. The method of claim 1, wherein the second step,
A second step of mixing polyol, dimethylol propionic acid (DMPA), and N-methyl-2-pyrrolidone (NMP) by stirring;
Step 2-2) of synthesizing a polyurethane prepolymer having an -NCO group at the end group by dropping dibutyltin dilaurate (DBTDL) and an isocyanate compound into the mixture of the above-mentioned 2-1 step and stirring the mixture, ;
Mixing the polyurethane prepolymer with triethylamine (TEA) followed by stirring to neutralize the polyurethane prepolymer; And
Method for producing a functional PET fiber, characterized in that it comprises a step 2-4 of dispersing by adding the powder of the functional ingredient to the neutralized polyurethane prepolymer. The method of claim 2,
The polyol is propylene glycol (PPG)
The isocyanate compound is isophorone diisocyanate (IPDI; Isophorone diisocyanate) method for producing a functional PET fiber, characterized in that. The method of claim 2,
In the third step, the bonding of the functional polyurethane prepolymer with the BHET is a method of producing a functional PET fiber, characterized in that by the synthesis reaction of the -OH group which is the end group of the BHET group and the -NCO group which is the end group of the polyurethane prepolymer. Functional PET fiber, characterized in that produced by the method of any one of claims 1 to 4.

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