JPH09275824A - Victoria lawn - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prepare a victoria lawn, comprising an acrylic fiber including an iron oxide-based ceramics as a constituent excellent in a photothermal conver sion, a heat-retaining property, a light-shielding property and a light resistance and suitable for agriculture and horticulture. SOLUTION: This victoria lawn contains preferably more than 5wt.% of an acrylic fiber including an iron oxide-based ceramics (suitably globular grains with an average size of less than 0.5μm as a primary particle) as a constituent. As the iron oxide-based ceramics, a compound of the formula Fe2 O3 or MO.Fe2 O3 (M is a divalent metal) is favorable. The objective material is preferable the one in which the amount of consuming-heat necessary to maintain a temperature of a hot plate at 30 deg.C is less than 6w/m<2> , when a plain woven lawn with a warp direction density of 24/inch and a welt direction density of 21/ inch is set up at 1cm on the hot plate of a warmth-retaining tester under an environment maintaining at 20 deg.C and 65% RH in accordance with ASTMOD-1518-85. The above acrylic fiber is favorably obtained by wet-spinning after dispersing the iron oxide-based ceramics into a solution of a fiber-forming polymer mainly comprising acrylonitrile.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ginseng having excellent light-shielding properties, light-heat conversion properties, and heat-retaining properties, and more particularly to an inexpensive ginseng suitable for agricultural and horticultural use.

[0002]

2. Description of the Related Art Ginseng requires many functions such as slow frosting, heat retention, light shielding (heat shielding), and various treatments have been conventionally performed to impart these functions. For example, hollow fibers that utilize the heat insulating properties of air are used to retain heat, and the presence of finely-divided titanium oxide, silicon oxide, etc. in the fibers is used to shade sunlight, and dyed with pigments or dyes. It is a method of imparting light absorption by making black in black by allowing Bonblack to exist in the fiber. Although the ginseng by these methods develops a specific function,
The above-mentioned various functions required for garments were not satisfied at one time. Generally, nylon, polyester, and vinylon are often used as the fiber material, but they have drawbacks such as poor light resistance.

[0003]

DISCLOSURE OF THE INVENTION The inventors of the present invention have solved the above problems and have a function of absorbing sunlight and converting light energy into heat energy efficiently, a light-shielding function of blocking sunlight, and a heat retaining property. An object of the present invention is to provide a ginseng having light resistance, and particularly an inexpensive ginseng suitable for agricultural and horticultural use.

[0004]

DISCLOSURE OF THE INVENTION The inventor of the present invention provides a fiber having photothermal conversion and heat retention, light shielding, and light resistance.
I have continued my earnest research. As a result, by adopting fibers in which iron oxide ceramics are uniformly dispersed in acrylic fibers, it has light-heat conversion properties and heat retention properties, light shielding properties,
The present invention has been completed by finding an inexpensive gauze cloth that also has light resistance. That is, the present invention resides in a gauze cloth characterized by using an acrylic fiber containing iron oxide ceramics as one component. The ginseng of the present invention is suitable for agricultural and horticultural use, but can also be used for the same purposes as commonly used ginseng such as decoration, artificial flowers, curtains, mosquito nets, and lining materials.

The photothermal conversion iron oxide ceramics of the present invention is preferably spherical, and the iron oxide ceramics used for the fibers have an average particle diameter of
It is preferably 1.0 μm or less.

Further, the iron oxide ceramics is Fe ₂
Iron sesquioxide represented by O ₃ or MO · Fe ₂ O
₃ (where M is a divalent metal).

Furthermore, the present invention is a plain weave having a warp density of 24 yarns / inch and a weft yarn density of 21 yarns, 20 ° C., 65% R
ASTM D-1518-85 under environment maintained at H
More preferably achieved by a cold gauze that consumes 6 W / m ² · ° C or less of heat consumed to maintain the hotplate temperature at 30 ° C when installed on a hotplate of a heat retention tester conforming to It

[0008]

BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below. The ginseng of the present invention is obtained by processing an acrylic fiber containing a photothermal conversion iron oxide ceramics into a ginseng. The acrylic fiber used in the present invention contains 80% by weight or more, preferably 85% by weight or more of acrylonitrile in the fiber. If the acrylonitrile content is less than this range, the light resistance is lowered, which is not preferable.

The iron oxide ceramics have a dark black color and can absorb light such as sunlight, especially all wavelengths in the visible light portion, and therefore can efficiently absorb light. Furthermore, it has been reported that black ceramics have a wider absorption spectrum than other colors, and thus are superior not only in the visible light region but also in efficient infrared absorption for conversion into heat energy. (“Far infrared ray utilization technology and its applications / examples”, Applied Technology Publishing, Hiroo Takashima), and is superior to the fiber containing other colors, especially white ceramics, in heat absorption and heat retention.

The photothermal conversion iron oxide-based ceramics used in the present invention is a dark black or brown iron oxide-based ceramic, which is iron sesquioxide represented by Fe ₂ O ₃ or MO.Fe ₂ It is represented by O ₃ (where M is a divalent metal), and is iron oxide generally called ferrite. Here, M in the ferrite is a divalent metal such as iron, manganese, zinc, copper, nickel, cobalt, magnesium and cadmium.

The photothermal conversion iron oxide ceramics used in the present invention preferably have an average particle diameter of 1.0 μm or less. From the viewpoint of practicality, it is more preferable to use iron oxide ceramics having an average primary particle diameter of 0.5 μm or less. In order to make the amount of the ceramics added to the fiber as small as possible, it is necessary to efficiently bring out the performance of the ceramics. Therefore, it is preferable to use the one having the smallest particle size. The area of light absorption directly affects the performance development of ceramics. If the average particle size exceeds 1.0 μm, the area of the ceramics to be absorbed per unit addition amount in the fiber decreases, so that the performance of the ceramics cannot be effectively exhibited. In addition, since the relative particle diameter relative to the fiber diameter becomes too large, discontinuity of the acrylonitrile-based polymer matrix is likely to occur, which is particularly noticeable with the aggregation of particles, and clogging of the spinneret during the spinning process And it is difficult to have good functionality.
By setting the average particle diameter to 1.0 μm or less, the content of the iron oxide-based ceramics may be at most 0.25 to 30% by weight.

The photothermal conversion iron oxide-based ceramics used in the present invention is preferably spherical. When the surface of the iron oxide ceramics has a planar structure, for example, in the case of scaly, cubic, polyhedral, etc., the incident light is reflected by the surface of the ceramic near the fiber surface, and the incident light is reflected by the fiber. Since the ceramics existing in the central part cannot be reached, the absorption efficiency is lowered. However, in the case of a spherical shape, the incident light can be repeatedly reflected on the spherical surface of the ceramic and reach the inside / center of the fiber, so that the light energy can be utilized to the maximum extent. This phenomenon is caused by ceramics in which needle-like crystals are arranged vertically on a substrate (Yamaguchi, T., “Physical Properties and Applications of Alumina”, Ceramics, Vol. 10, No. 9, p65).
0 (1975)), it is considered to be the same principle that the light absorption rate becomes very high. The term "spherical" as used herein means that the sphericity defined by the ratio of the minor axis / major axis of the iron oxide ceramic particle diameter is 0.8 or more. Further, when the iron oxide-based ceramic is in the form of scale, cube, polyhedron, etc., it is not preferable because the spinning machine and the weaving machine are abraded when the fiber is processed into the ginseng.

As a method for producing an acrylic fiber containing iron oxide-based ceramics to be used as a ginseng of the present invention, any method may be used as long as the iron oxide-based ceramics are dispersed in the fiber. It is preferable that the iron oxide-based ceramics be dispersed in a solution together with a fiber-forming polymer containing at least 85% by weight of acrylonitrile and then spun. Regarding the spinning method, any method such as melt spinning, wet spinning or dry spinning can be used, but when the spherical iron oxide ceramics used in the present invention is used, the particles can be obtained by a wet method. Since the surface of the iron oxide-based ceramics is naturally hydrophilic, wet spinning using an aqueous solvent, particularly a rhodanate salt or an aqueous zinc chloride solution as a solvent is preferable.

It is difficult to uniformly disperse the iron oxide ceramic particles, and it is generally necessary to disperse them at a high stirring speed for a long time. This is because iron oxide-based ceramics generally have magnetism, and particles are easily aggregated by magnetic force. Further, this magnetic cohesive force is remarkable when the particles are in contact with each other by a surface or a line, that is, in the case of a polygon, a needle, a cube, or a plate. However, in the case of spherical oxide ceramic particles, the particles are in point contact with each other, so that the cohesive force due to the magnetism is reduced and the dispersibility is improved.

In addition to the monocomponent type fibers which uniformly contain iron oxide type ceramics as the form of the acrylic type fibers, side-by-side type fibers in which the ceramics are contained in only one of the components by composite spinning, core sheath It is also possible to have a morphological structure such as mold fibers.

It is essential that the ginseng of the present invention comprises acrylic fibers containing iron oxide ceramics as one component, and the amount of constituents is 3 times that of acrylic fibers containing iron oxide ceramics. A gauze cloth containing at least 5% by weight, preferably at least 5% by weight. The other constituent fibers are generally known fibers such as synthetic fibers such as polyamide, polyester and vinylon, natural fibers such as wool and cotton, rayon and polynosic fibers.

The gauze cloth of the present invention is a plain weave having a warp density of 24 threads / inch and a weft density of 21 threads, 20 ° C. and 65% RH.
When installed on a hot plate of a heat retention tester conforming to ASTM D-1518-85 under the environment maintained at 1 cm,
The heat consumption required to maintain the hot plate temperature at 30 ° C is 6W
/ M ² · ° C or less. If the power consumption is higher than this range, the heat retaining property is deteriorated, and for example, the ground surface temperature is excessively decreased along with the decrease in the outside temperature at night, which hinders the growth of plants and the like, which is not preferable.

[0018]

The reason why the iron oxide ceramics-containing acrylic fiber used in the present invention is excellent in photothermal conversion and heat retention can be considered as follows. Infrared rays that provide thermal energy are electromagnetic waves with a wavelength longer than the red end of visible light.
Although it seems that color and infrared rays are not directly related to each other because the energy band is different from visible light, the spectrum of electromagnetic waves generated when a solid is heated is a continuous spectrum, so if the color of the radiator is black Would be well absorbed and converted into heat energy. Wave length is 2 to 20 μm
It is considered that they may reflect the heat energy of. Further, the excellent light resistance of the fiber may be based on the cyano group of the structure of the acrylic fiber.

[0019]

EXAMPLES The present invention will be described below in detail with reference to examples, but the gist of the present invention is not limited thereto. Parts and percentages in the examples are by weight unless otherwise specified.

Example 1 95 parts by weight of an acrylonitrile / methyl acrylate copolymer having a weight average molecular weight of 56000 was dissolved in 670 parts by weight of a 55% aqueous solution of sodium thiocyanate at 73 ° C. to give a spherical shape (sphericity 0.95). Fe ₃ O having an average particle diameter of 0.1 μm
_A spinning dope was obtained by adding 5 parts by weight of type ₄ iron oxide ceramic particles (M = Fe) and stirring for 5 hours. The spinning solution was spun into a 15% sodium thiocyanate aqueous solution at −2 ° C. using a spinning nozzle having a pore size of 0.07 mm and a number of pores of 20,000, followed by washing with water and stretching (total stretching ratio: 12 times),
After being subjected to dry densification, crimping treatment, relaxation heat treatment and oil treatment, it was cut into a constant length to obtain a fiber having a denier of 2 51 mm. In the production of fibers, workability was good without nozzle clogging, yarn breakage, winding, and the like. Also in the processing of the iron oxide ceramics-containing acrylic fiber, the workability in the steps such as spinning was good, and the workability was also excellent. In addition, no wear was observed in the devices such as the guide and the spinning machine through the series of steps.

Example 2 20 parts of the fiber of the present invention prepared in Example 1 and 80 parts of acrylic fiber (Exlan K8-2d × 51) were mixed-spun, carded, kneaded, roving and spinning according to a conventional method, 1/52
A yarn with a yarn count of yarn (thread-A) and a yarn with a yarn count of 1/17 (thread-B) were prepared. Furthermore, 10 parts of the fiber of the present invention prepared in Example 1 and acrylic fiber (Exlan K8-
2d × 51) A yarn (yarn-C) having a count of 1/17 meters was prepared from 90 parts. Using these yarns, a gauze cloth having the constitution described in Table 1 was prepared according to a conventional method. The polyester yarn is Toyobo Ester 738 low elongation type 2d x 5
1 mm (manufactured by Toyobo Co., Ltd.) was prepared according to a standard method 1 /
52 and 1/17 meter count yarns were used.

[0022]

[Table 1]

The prepared ginseng was placed on a hot plate 1c of a heat retention tester (manufactured by Kato Tech Co., Ltd.) according to ASTM D-1518-85 in an environment maintained at 20 ° C. and 65% RH.
The heat consumption required to maintain the hot plate temperature at 30 ° C. and 40 ° C. was measured. Moreover, as the evaluation of the photothermal conversion property, in an environment maintained at 20 ° C. and 65% RH,
The light source has a spectrum close to that of sunlight, and the color temperature is 5500 ° K, which is close to 6000 ° K of daytime sunlight.
50cm from the surface of the gauze placed on the heat insulating material with a 100W silica light bulb of 2800 ° K close to 00 ° K.
Irradiation was carried out for 30 minutes apart, and the temperature change between the lower part of the gauze cloth, that is, between the gauze cloth and the heat insulating material was recorded. The higher the maximum temperature reached, the better the photothermal conversion. The results are shown in Table 2.

[0024]

[Table 2]

As shown in Table 2, it was confirmed that the iron oxide ceramics-containing gauze of the present invention consumes less heat than the comparative gauze, is excellent in heat retention, and has a large light-heat conversion function. As a performance of the ginseng, a difference of 0.5 ° C. or more in the maximum temperature achieved by photothermal conversion is a sufficiently remarkable effect. When the garlic gauze A of the present invention was placed on a field of 5 cm and a germination test of daikon radish was carried out, it was confirmed that the seed germinated earlier than the comparative garlic gauze.

Examples 3 to 5 and Comparative Examples 1 to 4 Fibers containing ceramics or additives shown in Table 3 were prepared in the same manner as in Example 1. Then, according to Example 2, blending, carding, kneading, and roving were performed to prepare yarns of 1/52 and 1/17 meter counts containing 20 parts of the fiber. This yarn was made into a kansai cloth having the same structure as the kansai cloth A.
Strength of the fiber, elongation and guide of a series of processing steps from spinning to spinning, weaving, abrasion of the spinning machine, and heat consumption required to maintain the hot plate temperature at 30 ° C. by the method described in Example 2, The maximum temperature reached by a 500 W reflex lamp was measured. The results are shown in Table 3.

[0027]

[Table 3]

The iron oxide ceramics-containing fibers of the present invention of Examples 3 to 5 were excellent in fiber strength and fiber elongation, and the ginseng produced from these fibers had a high degree of photothermal conversion. In Comparative Example 1, the light-to-heat conversion property was good, but the abrasion of the device, the guide, and the spinning machine was remarkable in the manufacturing process and the subsequent processing process, and there was a problem in practicality. The photothermal conversion properties in Comparative Example 2 was observed with 53.3 ° C., heat consumption is 7.5 W / m ² · ° C. at 30 ° C., as high as 17.2W / m ² · ℃ at 40 ° C., warmth Was not recognized. This is probably because carbon black has a low far infrared radioactivity in the wavelength range of 2 to 20 μm. Furthermore, in Comparative Examples 3 and 4, yarn breakage in the spinning process,
Occurrence of wrapping was recognized. Further, the fiber strength and the fiber elongation were both low, and the fiber did not have the physical properties enough to withstand the subsequent steps. It was considered that the cause was that the average particle diameter was large and the particle shape was not spherical.

[0029]

[Effects of the Invention] The ginseng of the present invention comprises acrylic fibers containing iron oxide ceramics as one component, and has excellent light resistance of acrylic fibers and sunlight rays etc. due to iron oxide ceramics. Efficiently absorbs light energy and has excellent light-to-heat conversion properties that convert it into heat energy and also has excellent heat retention properties based on far-infrared radiation.
It protects against cold, protects flowers and foliage from shading, protects crops from strong winds and rain, and promotes seedling growth. Since the ginseng of the present invention can meet the above-mentioned requirements, not only for agricultural and horticultural purposes but also for general uses of ginseng for decoration, artificial flowers, curtains, mosquito nets, lining materials, etc., and further spread on the sea surface. It can also be appropriately adopted in fields such as the fishing industry, civil engineering and construction. There is no limitation on how to spread the ginseng, and it can be selected according to the intended use.

Claims (4)

[Claims] 1. A cheesecloth comprising an acrylic fiber containing iron oxide ceramics as a component. 2. The ginseng cloth according to claim 1, wherein the iron oxide ceramics are spherical particles and have an average particle diameter of 1.0 μm or less. 3. The iron oxide ceramics is represented by iron sesquioxide represented by Fe ₂ O ₃ or MO.Fe ₂ O ₃ (where M is a divalent metal). A gauze cloth according to any one of 1 to 2. 4. A warp density of 24 threads / inch and a weft density of 21.
When the plain weave gauze of this book is installed 1 cm above the hot plate of the heat retention tester conforming to ASTM D-1518-85 under the environment maintained at 20 ° C. and 65% RH, the hot plate temperature is 30.
The chilled gauze according to any one of claims 1 to 3, wherein the amount of heat consumed to maintain the temperature at 6 ° C is 6 W / m ² · ° C or less.