JPH03292832A - Composite fiber having excellent adhesion of marine product - Google Patents

Abstract

PURPOSE:To improve adhesion of marine product, budding property, dimensional stability, toughness and endurance of seaweeds by using a core-sheath composite fiber filament each containing a polyester as the core component and a polyamide as the sheath component. CONSTITUTION:A polyester fiber obtained by subjecting a polyester having >=0.7 intrinsic viscosity to melt spinning at 270-330 deg.C and having >=150X10<-3> double refractive index is used as a core component and a polyamide obtained by subjecting a polyamide having >=2.8 relative viscosity in sulfuric acid to melt spinning at 260-330 deg.C and having 40X10<-3> double refractive index is used as a sheath component and these components are introduced into a composite spinning pack and passed through a spinneret for composite spinning and spun and the resultant undrawn yarn is drawn at >=150 deg.C and a draw ratio of 1.4-4.0 times to provide the aimed composite fiber forming fine pores having 0.1-10mu width and 100-10000mu length in sheath component fiber and having >=5g/d strength, >=60g/d initial tensile resistance and >=15% water-including ratio.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention has excellent adhesion to seaweeds such as nori and wakame, and marine products such as fish eggs and young shellfish, as well as excellent sprouting properties of the seaweeds. The invention relates to composite fibers. More specifically, it has excellent adhesion and budding properties for seafood,
The present invention also relates to a composite fiber that has excellent dimensional stability when immersed in seawater and when drying, has high modulus, has improved toughness and durability, and has excellent adhesion to marine products.

[Prior Art] In recent years, polyvinyl alcohol fibers with excellent adhesion and sprouting properties, and fibers made by combining polyvinyl alcohol fibers with polyamide fibers or polyester fibers as reinforcing materials have been widely used as materials for seaweed nets. There is.

Fibers for seaweed nets do not rot even when immersed in seawater, have excellent toughness and durability, and are easy to wet when immersed in seawater to improve the germination of seaweed. Of course, even when exposed above seawater due to low tide, it is necessary to retain moisture to avoid ``burn''.

The above-mentioned polyvinyl alcohol fibers and fibers for seaweed netting made by combining polyvinyl alcohol fibers with polyamide fibers or polyester fibers have been adopted as meeting the above requirements. It has drawbacks such as poor dimensional stability during processing, and improvements have been desired.

Therefore, proposals have been made to solve the above problems, for example, in Japanese Patent Application Laid-Open No. 56-61930,
A base fiber for adhesion to marine products is disclosed, which is made of polyester fiber mixed with an oxyalkylene compound having a molecular weight of 1,000 or more and 100,000 or less, and has a specific cross-sectional shape and surface irregularities.

[Problems to be Solved by the Invention] The oxyalkylene compound-containing polyester fiber, which is a marine product adhesion base fiber described in JP-A-56-61930, is required as a seaweed net when compared with conventional polyester fibers. Although it is an excellent technology with improved functionality, when compared to the recently used fibers for seaweed netting, which are a combination of polyvinyl alcohol fibers and polyamide fibers with irregular cross sections, it is especially difficult to use the polyester containing the oxyalkylene compound. Fibers are adhesive to seafood,
It cannot be said that it has been sufficiently improved in terms of sprouting ability and water retention.

The object of the present invention is to provide seaweed such as seaweed and wakame, and marine products such as fish eggs and young shellfish, particularly seaweed, with excellent adhesion or sprouting properties, and improved toughness and durability of the adhesion of marine products. This provides an excellent composite fiber.

Furthermore, the present invention provides a composite fiber that has high strength, high toughness, moderate high modulus, excellent dimensional stability, and excellent adhesion to marine products.

In particular, the dimensional stability during repeated seawater absorption and drying, which was a drawback of seaweed nets made by combining polyvinyl alcohol fibers and polyamide fibers, has been significantly improved, making it a composite fiber that is ideal for seaweed nets and has excellent adhesion to marine products. It provides:

[Means and effects for solving the problems] The present invention has the following features: (1) A composite fiber with excellent adhesion to marine products, in which the filament of the composite fiber has a core-sheath whose core component is polyester and whose sheath component is polyamide. Consisting of composite fiber filaments, the proportion of the core component in the fiber filaments is 30 to 30.
90% by weight, the polyester core component has an intrinsic viscosity [η] of 0.7 or more and a birefringence of 150×10-” or more, and the polyamide sheath component has a sulfuric acid relative viscosity ηr of 2.8 or more and a birefringence of 40×10-8 above, and the entire polyamide sheath component fiber has a width of 0.1 to 10 μm and a length of 100 to 1000 μm.
Composite fiber with excellent adhesion to seafood, characterized by the formation of micropores of 0μ.

(2) In the composite fiber described in (1) above, which has excellent adhesion to marine products, the strength of the composite fiber is 5 g/d.
As described above, the composite fiber has excellent adhesion to marine products, and is characterized by having an initial tensile resistance of 60 g/d or more and a water holding rate of 15% or more.

Consisting of

The composite fiber of the present invention that has excellent adhesion to marine products is a core-sheath composite fiber consisting of a core component of each filament forming the composite fiber or polyester, and a sheath component of the polyamide, and a polyamide sheath component of the filament. Width 0 throughout
．． It is characterized by the formation of micropores with a diameter of 1 to 10 microns and a length of 100 to 10,000 microns. That is, the polyester core component of the filament exhibits functions such as water absorption, dimensional stability during drying, and high modulus, and the micropores formed in the polyamide sheath component exhibit functions such as water retention, adhesion of marine products, and sprouting ability. In addition, the toughness, durability, and other functions of net fabrics such as seaweed nets are achieved by the composite structure of a high-strength polyester core component and a flexible polyamide sheath component.

The polyester used as the core component of each filament forming the composite fiber with excellent adhesion to marine products (hereinafter referred to as the "invention fiber") according to the present invention is polyester made of polyethylene terephthalate, polybutylene terephthalate, cyclohexane dibutanol and terephthalic acid, polyester (ethylene-2,6-dicarboxylate), poly(ethylene-1,2-diphenoxy-P,P'-dicarboxylate), and parahydroxybenzoic acid/4. 4'
-Dihydroxybisphenol/terephthalic acid copolyester, parahydroxybenzoic acid/4. 4'-
Dihydroxybisphenol/terephthalic acid/isophthalic acid copolyester, 6-oxy-2naphthonic acid/
Melt-spun polyesters such as parahydroxybenzoic acid/terephthalic acid copolymer polyester, especially polyethylene terephthalate, poly(ethylene-2,6
-dicarboxylate) and poly(ethylene-1,2-diphenoxy-P,P'-dicarboxylate). The above core component polyester contains 10 mol% or less of the tertiary polyester.
The components may be copolymerized or may be a mixed polymer of polyesters.

Intrinsic viscosity of the core component polyester related to the fiber of the present invention [η]
By setting 0.7 or more, the strength of the obtained fiber of the present invention can be increased to 5. It can be Og/d or more.

On the other hand, the polyamide used as the sheath component of the composite fiber according to the present invention is selected from ordinary polyamides such as polycabramide, polyhexamethylene adipamide, polytetramethylene adipamide, polyhexamethylene dodecamide, and polyhexamethylene dodecamide. Polymers obtained by blending or partially copolymerizing the above polymers can also be used, but polyhexamethylene adipamide, polycapramide and polytetramethylene adipamide are particularly preferred.

The polyamide sheath component polymer also needs to have a high degree of polymerization in order to form the high-strength conjugate fiber of the present invention, and has a sulfuric acid relative viscosity (ηr) of 2.8 or more, preferably 3.0 or more.

It is preferable that the polyamide component contains a copper salt and other organic or inorganic compounds as a thermal oxidative deterioration inhibitor. Usually, copper salts such as iodized steel, copper acetate, copper chloride, and copper stearate are used in an amount of 30 to 500 ppm as copper, and alkali metal halides such as potassium iodide, sodium iodide, and potassium bromide are added in an amount of 0.01 to 0.0 ppm. 5% by weight, and if necessary, 10 to 500 ppm of organic or inorganic phosphorus compounds as phosphorus.

The proportion of the polyester core component of the composite fiber according to the present invention is 30 to 90% by weight. If the core component is less than 30% by weight, it is difficult to achieve the desired levels of modulus and dimensional stability as a composite fiber. On the other hand, if the polyester core component exceeds 90% by weight, the polyamide layer of the sheath component that forms micropores becomes a thin layer, and the effects of the fibers of the present invention, such as water retention, adhesion, or sprouting properties, may not be sufficiently obtained. be.

The fiber of the present invention is characterized in that both the polyester core component and the polyamide sheath component are relatively highly oriented and crystallized. That is, the birefringence (Δn) of the polyester core component
is 150X10-'' to 200X10''3. 150
If the strength (T/D) of the composite fiber is less than 5.
g/d or more, the initial tensile resistance (M i ) is 60 g
/d or more cannot be achieved.

On the other hand, the birefringence (Δn) of the polyamide component, which is the main component constituting the sheath, is 40X10-a or more, usually 45X10-a.
”This indicates relatively high orientation.

If the birefringence is less than 40 x 10-'', this corresponds to the fact that the micropores formed in the polyamide sheath component, which is one of the important characteristics of the fiber of the present invention, are not formed uniformly and stably.

The micropores formed in the polyamide sheath component have a width of 0.1~
It has a size of 10μ and a length of 100 to 10,000μ, and is formed almost uniformly over the entire polyamide sheath component. However, when observing the cross section of the fiber, the pore size in the surface layer is slightly larger, and the size of the pores in the inner layer, that is, the polyester core, is slightly larger. Although it becomes slightly smaller near the interface with the component, both widths and lengths are within the above ranges.

The micropores are extremely coarse amorphous molecular regions formed between crystal lamellae that are highly crystallized and stacked in the fiber axis direction in the fiber structure of the polyamide sheath component. Therefore, each micropore is characterized by being continuously connected to each other. Although the micropores differ slightly depending on the type of polyamide and manufacturing conditions, they are formed with a size within the above range.

The microporous structure of the polyamide sheath component not only improves water retention, adhesion, and sprouting properties, which are the objectives of the present invention, but also improves toughness when combined with the core polyester component to form nets such as seaweed nets. , which is extremely important for improving durability.

The fiber of the present invention characterized by the above structure is 5. Og
It is preferable that the material has a high strength of /d or more, an initial tensile resistance of 60 g/d or more, and a water holding rate of 15% or more, and by satisfying these physical properties, it has excellent adhesion to seafood. Composite fibers can be used stably for long periods of time under harsher conditions, making them particularly suitable for seaweed nets, etc.

The fiber of the present invention having the above-mentioned characteristics is produced by the novel method shown below.

The polyester core component of the composite fiber according to the present invention is the specific polyester polymer described above, and has an intrinsic viscosity [η
] of 0.70 or more is used. The polyamide polymer used as the main component of the sheath is the above-mentioned specific polyamide polymer, and is a high polymerization degree polymer having a relative viscosity of 2.8 or more, usually 3.0 or more in terms of sulfuric acid relative viscosity.

It is preferable to use two extruder type spinning machines for melt spinning the polymer. The polyester for the core component melted in each extruder is melted in one extruder at a melting temperature of 270 to 330°C, taking into account the melting point and melt viscosity of the polymer used, and the polyamide component for the sheath component is similarly melted. It is melted in the other extruder at a temperature of 260 to 330°C taking into consideration the melting point and melt viscosity of the polymer used. each polymer from 270 to 33
The fiber is introduced into a composite spinning bag at a temperature of 0° C., and passed through a composite spinning nozzle to spin a composite fiber having a polyester core and a polyamide sheath.

The spinning speed is preferably 1500 m/min or higher. Immediately below the spinneret, a high-temperature atmosphere of 200° C. or higher, preferably 260° C. to 400° C., is created over a distance of 10 cm or more and within 1 m by providing a heat insulating cylinder or a heating cylinder. After passing through the above-mentioned high-temperature atmosphere, the spun yarn is quenched and solidified with cold air, and then, after being applied with an oil agent, it is taken off by a take-off roll that controls the spinning speed.

Control of the high-temperature atmosphere immediately below the spinneret is particularly important in order to maintain stringiness during high-speed spinning. The taken-off undrawn yarn is usually drawn continuously without being wound up, but it can also be drawn in a step after being wound up. For the purpose of grasping the physical properties of the undrawn yarn before drawing, the birefringence of the undrawn yarn sampled as it is after passing over a take-up roll is preferably 15X10-3 to 40X10 for the polyamide sheath component.
-", the polyester component is preferably 15X10-3~
It is 80×10-B.

In particular, it is important that the degree of orientation of the polyamide sheath component is such that it is taken off as an undrawn yarn within the above birefringence range in order to form a uniform micropore structure. Another reason is that the peeling durability of the core-sheath interface of the composite fiber according to the present invention is improved by starting from a relatively highly oriented undrawn yarn and subjecting it to the subsequent drawing and heat treatment. be. The reason for this is not clear, but it is probably because the stretching behavior is more similar when both the polyester core component and the polyamide sheath component are oriented and crystallized, and the stretching ratio may be small. It is thought that this increases the shrinkage stress of the polyamide sheath component in the radial direction and contributes to the improvement of the peel durability of the composite interface.

Next, the undrawn yarn has a temperature of 150°C or higher, preferably 180°C.
It is hot stretched at a temperature of ℃ or higher. The stretching is preferably carried out in two or more stages, and the stretching ratio is in the range of 1.4 to 4.0 times.

By the above method, initial strength is 5 g/d or more, initial tensile resistance is 60 g/d or more, usually 6 g/d or more, respectively.
After obtaining a conjugate fiber of 7 g/d or more, the following treatment is performed to form micropores of 0.1 μ to 10 μ throughout the polyamide sheath component fiber of the conjugate fiber.

In other words, the composite fibers have a weight of 2.0 kg/cm"G or more, 12
Perform high-temperature, high-pressure steam or high-temperature pressurized hot water treatment at a temperature of 1°C or higher. The treatment may be carried out, for example, by continuously passing the yarn through a pressurized steam treatment cylinder having a sealing mechanism such as a labyrinth at the front and rear, or by steam or pressurized hot water treatment in an autoclave. For continuous processing, from 0°1 second
The process is performed for several minutes, or in the case of batch processing, for several minutes to several tens of minutes.

The fiber thus obtained has the characteristics of the fiber of the present invention.

Next, it will be explained based on Examples, but the main text of the present invention specification,
and definitions of fiber properties and cord properties described in the examples,
And the measurement method is as follows.

"Characteristics of Polyester Core Component Fiber" The polyamide component, which is the main component of the core of the sample, was dissolved and removed with formic acid, and the polyester core component fiber portion was subjected to measurement.

(a) Intrinsic viscosity ([η]): A sample was dissolved in an orthochlorophenol solution and measured at 25°C using an Ostwald viscometer.

(b) Birefringence (Δn): Measured by the usual Berek compensator method using sodium D line as a light source.

[Characteristics of polyamide component fiber of sheath] (c) Relative viscosity of sulfuric acid (ηr): A sample was dissolved in formic acid, and the dissolved portion was reprecipitated by a conventional method, washed and dried, and used as a measurement sample.

1 g of the sample was dissolved in 25 cc of 98% sulfuric acid and measured at 25° C. using an Ostwald viscometer.

(d) Birefringence (Δn): Only the sheath component in the surface layer was measured from the side by the interference fringe method using a transmission quantitative interference microscope manufactured by Carl Zeiss Jena (East Germany).

"Characteristics of Composite Fiber" (e) Strength (T/D), Elongation (E), Initial Tensile Resistance (Mi): The strength and initial tensile resistance were in accordance with the definition and measurement method of JIS LIO17. The specific conditions for the tensile test to obtain the SS curve are as follows.

Take the sample into a whole shape, leave it in a temperature and humidity controlled room at 20℃ and 65% RH for more than 24 hours, and then
The measurement was carried out using a 4L" type tensile tester (manufactured by Orientic Co., Ltd.) at a test length of 25 cm and a tensile speed of 30 cm/min.

(f) Water holding rate: Take a 20g sample adjusted in a temperature and humidity adjustment room at 25°C and 65% RH, immerse it in a 20°C water bath for 1 hour, take it out, and hang it in the temperature and humidity adjustment room for 10 minutes. I lowered it and let it air dry. The water holding rate was determined from the following formula, where Wo was the weight of the sample before immersing it in the water bath, and W was the weight of the sample air-dried after immersing it in the water bath.

Water retention rate = [(W, -WO) /WO) X 100% (g)
Micropore size and morphology observation Hitachi, Ltd. field emission scanning electron microscope S-80
Measurement was carried out using Type 0 at an accelerating voltage of 6 kV.

The surface and inner layer of the fiber were observed, and the pore size was measured.

[Examples] Examples 1 to 4 and Comparative Examples 1 to 5 Intrinsic viscosity [η] 1.02, carboxyl end group concentration 9.
9eq/10'H polyethylene terephthalate (PE
T) and 0.02% by weight of iodized steel and 0.02% by weight of potassium iodide.
NyO:/66 (N66: sulfuric acid relative viscosity ηr3.3) containing 1% by weight was separately melted in two 40φ engineered spinners, guided into a composite spinning pack, and then passed through a core-sheath composite spinneret. PET core, N66 sheath
The polymer was spun into a composite fiber. The proportions of the core component and sheath component were varied as shown in Table 1. The hole diameter of the cap is 0.4mm
φ and 120 holes were used. The core PET polymer was melted at 295°C, the sheath N66 was melted at 290°C, and the spinning back temperature was set at 295°C. A 15 cm heating cylinder was attached directly below the mouthpiece, and the atmosphere inside the cylinder was heated to 290°C. The ambient temperature is the ambient temperature measured at a position 10 cm below the mouth surface and 1 cm away from the outermost thread. A horizontal uniflow chimney with a length of 120 cm was attached below the heating cylinder, and cold air at 20° C. was blown at a speed of 30 m/min from a direction perpendicular to the yarn to cool it.

Then, after applying the oil, the yarn speed was increased to 2 with a take-up roll.
After controlling the speed to 000 m/min, the film was continuously stretched without being wound up. The film was stretched in three stages using Nelson type rolls, then heat treated while being relaxed by 3%, and then wound up.

The stretching conditions were a take-up roll temperature of 60°C, a first stretching roll temperature of 120°C, a second stretching roll temperature of 200°C, a third stretching roll temperature of 230°C, and a tension adjustment roll after stretching that was not heated. The first stage stretching ratio was set to 75% of the total stretching ratio.

The yarn was produced by varying the spinning speed, total draw ratio, etc., and the discharge amount was varied in accordance with the spinning speed and draw ratio so that the fineness of the drawn yarn was about 960 denier.

The obtained composite fiber was wound back onto an aluminum bobbin, and then immersed in a water bath placed in an autoclave. Next, water vapor was blown into the autoclave and treated with 6.0 kg 7 cm'' for 15 minutes to obtain a composite fiber having micropores in the N66 sheath.

The above conditions and the properties of the obtained composite fibers are shown in the table. (Example 1, Example 2) In addition, nylon 46 was used instead of nylon 66 used as the sheath component of the composite fiber, and the core PET/
A composite fiber with sheath N46 was obtained.

This composite fiber was placed in an autoclave in the same manner as in Example 1.
．． A composite fiber having micropores in the N46 sheath was obtained by processing at 5 kg/cm2. (Example 3, Example 4) Comparative Example 1 compares the case where the composite fiber spun under the conditions of Example 2 is not subjected to microporization treatment, and the case where the composite fiber spun under the conditions of Example 4 is not subjected to microporization treatment Example 2 is used.

The spinning conditions of Examples 1 to 4 and Comparative Examples 1 and 2 and the properties of the obtained fibers are tabulated. In addition, commercially available polyamide fibers for seaweed netting (Comparative Example 3), polyester fibers (Comparative Example 4), and polyvinyl alcohol fibers (
The properties of Comparative Example 5) are also shown in the table.

Next, among the fibers of the present invention, Example 2, Example 4, and commercially available fibers for seaweed net were knitted to prepare seaweed nets.

The net was made under normal conditions: twisted yarn, knitted net (knotless net), temporary longitudinal drawing (1 minute in 80°C warm water), temporary weft drawing (3 minutes in 100°C steam), oil removal (4 days underwater) ), air drying, nutritional resin processing (polyvinyl alcohol and minerals), and drying set (2 hours in dry heat at 100°C) to make a seaweed net. Next, seedlings were collected using each seaweed net, and the adhesion of seaweed spores, growth status, water retention, dimensional stability, and durability were evaluated and shown in the table. The microporous composite fiber of the invention had the best seaweed network properties.

In the seaweed net properties in the table, ◯ indicates extremely good, △ indicates somewhat good, × indicates poor, and - indicates that the seaweed net properties were not investigated.

(Left below) [Effects of the invention] The composite fiber of the present invention, which has excellent adhesion to marine products, has superior water retention and adhesion properties compared to polyvinyl alcohol fibers, polyamide fibers, and polyester fibers that have been conventionally used as substrate fibers for adhering marine products. Or, significant improvements have been made in budding properties, dimensional stability, durability, etc.

Furthermore, since the fiber of the present invention has a high modulus, when it is made into a net fabric such as a seaweed net, it has tension and excellent shape retention. Furthermore, since the toughness as a net fabric is significantly improved, it is suitable as a base layer fiber for adhering marine products.

Claims (2)

[Claims] (1) A composite fiber with excellent adhesion to marine products, in which the filament of the composite fiber is composed of a core-sheath composite fiber filament whose core component is polyester and whose sheath component is polyamide, and the ratio of the core component to the fiber filament is 30%. ~
90% by weight, the intrinsic viscosity [η] of the polyester core component is 0.7 or more, the birefringence is 150 × 10^-^3 or more, and the sulfuric acid relative viscosity ηr of the polyamide sheath component is 2.8 or more,
Birefringence is 40 x 10^-^3 or more, and the entire polyamide sheath component fiber has a width of 0.1 to 10μ and a length of 100 to
Composite fiber with excellent adhesion to seafood, characterized by the formation of micropores of 10,000μ. (2) In the composite fiber that has excellent adhesion to marine products as described in claim 1, the strength of the composite fiber is 5 g/
d or more, an initial tensile resistance of 60 g/d or more, and a water holding rate of 15% or more.