JP2003097089A - Snowfall prevention net - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a snowfall prevention net which can be manufactured by simple machining and having heat generating property. SOLUTION: This snowfall prevention net is a net structure formed by adhesion of high hygroscopic fine particles and having an n-polygon (n>=3) where the shortest distance at an opening size of strand is 2 mm or more. The maximum temperature rise in absorbing humidity or water is 3 deg.C or more. Heat generation in absorbing humidity is kept for 30 minutes or more, and/or heat generation in absorbing water is kept for one or more minutes. The high hygroscopic fine particles are fixed through a hydrophilic resin.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a snow cover material, and more particularly to a snow cover net.

[0002]

2. Description of the Related Art Conventionally, a snow-prevention net has been intended to prevent snow from falling on a structure by receiving snowfall. This means that snow will land on the net. Therefore, it was unsuitable for applications where it is not desirable for snow to accumulate (for example, a net as a mark). Further, there is a method in which an electric heater is arranged inside the net to prevent snow from accumulating due to heat generated by the electric heat.

[0003]

DISCLOSURE OF THE INVENTION The present invention provides a snow cover net which can be manufactured by simple processing and is excellent in heat generation.

[0004]

The present invention has the following technical constitution for solving the above problems. That is, 1. An n-sided (n ≧ 3) net-like structure having at least a mesh size and a minimum distance of 2 mm or more, to which highly hygroscopic fine particles are adhered, and the maximum temperature rise during moisture absorption and / or water absorption is 3 ° C. or more. A snow cover net characterized by being present.

2. The snow accumulation suppression net according to the first aspect, characterized in that heat generated when absorbing moisture is maintained for 30 minutes or more and / or heat generated when absorbing water is maintained for 1 minute or more.

3. The maximum snowfall at the time of water absorption is 8 ° C or more, the snow-covering net according to the first or second aspect.

4. The snow accumulation suppression net according to any one of 1 to 3, wherein the highly hygroscopic particles are organic particles.

5. The highly hygroscopic organic fine particles are polystyrene-based, polyacrylonitrile-based, polyacrylic acid ester-based, or polymethacrylic acid ester-based vinyl polymers, and have sulfonic acid groups, carboxylic acid groups, phosphoric acid groups, or their metals. The snow cover net according to the fourth aspect, which is a crosslinked polymer having at least one hydrophilic group of a salt and crosslinked with any of divinylbenzene, triallyl isocyanate or hydrazine.

6. Highly hygroscopic fine particles have an average particle size of 2 μm
The snow accumulation suppression net according to any one of 1 to 5, which is less than.

7. 7. The snow accumulation suppression net according to any one of 1 to 6, wherein the highly hygroscopic fine particles are fixed to the net-like structure through a hydrophilic resin.

8. Mass ratio of highly hygroscopic fine particles and hydrophilic resin is 1/1 to 20/1, The snow accumulation suppression net in any one of the 1st-7th characterized by the above-mentioned.

9. 9. The net-shaped structure is a knitted fabric, a woven fabric, a net, a string-shaped body or a net-shaped resin molded body composed of natural fibers, synthetic fibers or mixed fibers of these fibers. Snow control net.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below. The net-like structure used in the present invention is a polyester-based, polyamide-based, polyacrylonitrile-based, polyethylene-based, polypropylene-based, polybutylene terephthalate-based, polytetramethylene terephthalate-based, polyurethane-based, polyphenylene sulfide-based synthetic fibers, Chemical fibers such as rayon and acetate,
It is a structure composed of a net-shaped knitted fabric, a woven fabric, a net, a string-shaped body, a net-shaped resin molded body or the like made of natural fibers such as cotton, hemp, silk, wool, and feathers, or a mixed material thereof. The fiber material is not particularly limited. For the purpose, if biodegradability is required, a biodegradable material may be used, and if high strength is required, that material may be used.
Polyester fiber is desirable in terms of price and handling.

The mesh size of the net structure used in the present invention is at least 2 mm or more. The mesh size referred to here is the distance between the inner sides of the holes (when n = 3, the distance between the bisector of the shortest side and its diagonal). This is because wind (so-called blizzard state) is often involved during snowfall, and if the mesh size is less than 2 mm, the net will be damaged by wind. The upper limit of mesh size is not particularly limited. Also,
The shape of the net is not particularly limited, and it is needless to say that the shape is not limited to an n-value from an isosceles triangle to a polygon, and as the value of n increases, the shape of the net naturally becomes a circular shape.
Around 8 is desirable. The fiber material is not particularly limited. For the purpose, if biodegradability is required, a biodegradable material may be used, and if high strength is required, that material may be used.
Polyester fiber is desirable in terms of price and handling.

Highly hygroscopic fine particles of the present invention (hereinafter referred to as high moisture absorption /
Also referred to as water-absorbing exothermic particles. ) Is not particularly limited in terms of chemical structure as long as it is a fine particle that exhibits exothermicity when absorbing moisture or absorbing water. For example, inorganic type such as hygroscopic silica, or hygroscopic polyurethane type, polyamide type,
It is possible to apply various organic fine particles such as polyester-based and polyacrylate-based, but particularly high moisture-absorption / water-absorption exothermic organic fine particles are preferable, and examples thereof include polystyrene-based, polyacrylonitrile-based, polyacrylic ester-based, and polyacrylic ester-based. A methacrylic acid-based vinyl polymer having a sulfonic acid group, a carboxylic acid group, a phosphoric acid group, or at least one hydrophilic group of metal salts thereof, and having divinylbenzene, triallyl isocyanate, or It is a crosslinked polymer fine particle crosslinked with any of hydrazine. Since the highly hygroscopic fine particles themselves have antibacterial and antibacterial properties, they are suitable for a snow cover net.

The particle size of the highly hygroscopic fine particles is preferably as small as possible from the viewpoint of moisture absorption / water absorption heat generation rate / heat generation efficiency, uniform adhesion, texture and abrasion resistance, and an average particle diameter of less than 2 μm is more preferable.

The method for applying the highly hygroscopic fine particles of the present invention is a method of directly kneading into a fiber, a film or a resin layer, or coating the surface layer of a knitted fabric, a woven fabric, a non-woven fabric, a fleece, a film or a resin molded product through a binder resin. Examples of the method include attaching by dipping, spraying and the like, but the latter method of attaching via a binder resin is preferable from the viewpoint of moisture absorption / water absorption heat generation rate / heat generation efficiency.

As the binder resin, a usual impregnation method,
Examples of the resin include silicone-based, urethane-based, acrylic-based, polyester-based, polyamide-based, and polyethylene oxide-based resins that can be applied to the padding method, coating method, and spray method, and are not particularly limited, but hydrophilic, that is, hygroscopicity, water absorption. It is desirable to use a type that has excellent properties and moisture permeability, does not inhibit the excellent hygroscopicity and water absorption of the highly hygroscopic fine particles, and has an excellent binder function that can effectively bond and fix the highly hygroscopic fine particles and the structure. As a particularly preferable hydrophilic resin binder, as a hydrophilic segment, a polyalkylene oxide addition type, a polar hydrophilic group type such as a sulfonate or a carboxylate, a hydrophilic silicone resin having amide modification or the like introduced therein, a hydrophilic urethane Examples thereof include resins, hydrophilic polyamide resins, and hydrophilic polyethylene oxide resins, which have high hygroscopicity and moisture permeability of the resin themselves and do not impair water absorption. The moisture permeability of the resin as used herein means the moisture permeability in a non-porous film state. Even in the case of a resin having a high moisture permeability expressed in a microporous film, a binder resin having a low hygroscopicity and a low water absorptivity of the resin itself masks and lowers the excellent moisture absorption / heat generation characteristic of the high moisture / water absorption heat-generating fine particles. In addition, in order to improve the durability, these high moisture absorption / water absorption exothermic fine particles and hydrophilic resin binder are combined with various crosslinking agents such as isocyanate type, methylol type, ethyleneimine type, polyfunctional aziridinyl type, and metal salt type. You may use together in the range which does not reduce the original moisture absorption / water absorption.

The compounding ratio of the highly hygroscopic / water-absorbing exothermic fine particles and the hydrophilic resin in the present invention and the amount of these adhering greatly affect the hygroscopic / water-absorbing exothermicity. The compounding ratio of the highly hygroscopic / water-absorbing exothermic fine particles and the hydrophilic resin is slightly different depending on the hydrophilic level of the hydrophilic resin, but it is usually desirable to use the compounding ratio of 1/1 to 20/1, preferably 10/1 to 19/1. More preferably, the compounding ratio of 15: 1 to 19/1,
In particular, the smaller the blending ratio of the hydrophilic resin, the better the moisture absorption / water absorption exothermicity can be exhibited. However, when the hydrophilic resin is extremely small, or when the hydrophilic resin is not used in combination, the abrasion resistance of the highly hygroscopic / water-absorbing heat-generating fine particles adhered to the surface of the structure is deteriorated and the particles easily fall off. On the contrary, if the blending ratio of the hydrophilic resin is high, even if it is a hydrophilic resin, high moisture absorption /
Since the moisture absorption / water absorption inherent to the water absorption / heat generation fine particles is often impaired, the moisture absorption / water absorption heat generation rate and the heat generation amount are extremely reduced due to the masking effect. Of course, when the moisture absorption / water absorption of the hydrophilic resin is equal to or higher than that of the high moisture absorption / water absorption exothermic fine particles, the compounding ratio of the hydrophilic resin can be increased.

Since the exothermicity of the snow cover net of the present invention is based on the heat of adsorption reaction generated when the substance absorbs moisture or absorbs water, the highly hygroscopic / water-absorbing fine particles and the combined hydrophilic resin contained in the net-like structure. It depends on the hygroscopic ability and / or the water absorbing ability of the binder and the adhered amount. That is, the higher the hygroscopic / water-absorbing fine particles, and the finer the hydrophilic resin binder having a higher hygroscopic or water-absorbing level, the larger the heat production due to the adsorbed moisture, the faster the heat generation rate, and the longer the heat retention time. Of course, since such a moisture absorption / water absorption is possessed by the structure substrate alone, in order to realize more effective moisture absorption / water absorption exothermicity, the moisture absorption rate of the applied moisture absorption / water absorption exothermic fine particles (20 ° C., 65% RH ) Is preferably 25% or more, more preferably 40% or more. In addition, the combined hydrophilic resin does not hinder the hygroscopicity / water absorption of the moisture absorption / water absorption exothermic fine particles as much as possible.
C., 65% RH) 3 to 50% is preferable. That is, in order to obtain an effective moisture absorption / water absorption exothermicity, the structure having a high degree of moisture absorption / water absorption exothermicity of the present invention has a moisture absorption rate as low as possible, more preferably close to a completely dry (absolute dry) state. It is essential to store it in the state. On the other hand, the structure that has adsorbed moisture at a saturated moisture absorption rate or higher and has completed heat generation is cooled by heat radiation and drops to the initial temperature, but if it is dried again to remove the adsorbed water, the original excellent moisture absorption / Water absorption and exothermicity reappear.

The moisture absorption exothermicity in the gas phase heats up at an appropriate rate and maintains the exothermicity for a relatively long time, while the water absorption exothermicity in the liquid phase gives a rapid exothermicity, while the adsorbed water If the amount is too large, the remarkable heat generation effect may not be obtained, so it is important to control the amount of attached water. In particular, when it is desired to heat rapidly, such as in an emergency, the water absorption and heat generation function of the present invention is effective, and when combined with the moisture absorption and heat generation function that has a long heat generation retention time, it is possible to design a product for a more sophisticated snow cover net.

According to the present invention, the type and the amount of the highly hygroscopic / water-absorbing exothermic fine particles are optimized, and the net-like structure adhered via a proper hydrophilic resin binder is used for moisture absorption and / or water absorption. Maximum temperature rise is 3 ℃ or more, preferably 4
℃ or more, more preferably 5 ℃ or more, rapid (3 ~
The maximum temperature rise during water absorption (for 5 seconds) is 8 ° C or higher,
Moreover, the total heat generation of moisture absorption / water absorption heat generation rate, heat generation amount, heat generation retention time, such as heat generation retention time when moisture absorption is 30 minutes or more, or heat generation retention time when water absorption is 30 seconds or more, more preferably 1 minute or more In terms of performance, excellent moisture absorption /
Water absorption and exothermicity are obtained.

High moisture absorption / water absorption heat generation in a snow cover net
The amount of the hydrophilic fine particles is usually 5 g / m²The above is preferable.
More preferably 10 g / m²Above, more preferably 20 g
/ m ²That is all. The larger the amount, the greater the heat-generating effect.
This is because. 5 g / m²If it is less than the above, the exothermic effect is small.

In addition to these excellent high moisture absorption / water absorption exothermic properties, the snow accumulation control net of the present invention has antibacterial and deodorant properties, antibacterial properties,
It is also possible to exhibit multi-functionality such as deodorant property, pH buffering property, antistatic property, SR antifouling property, and acid rain resistance.

[0025]

The present invention will be described in detail below with reference to examples, but the present invention is not limited thereto. Below, what is described simply as part and% means on a mass basis. Further, the measurement and evaluation of the net-like structure in this example were carried out by the following methods.

<Absolute dry mass> After drying the sample at 110 ° C for 6 hours, the sample was placed in a desiccator containing silica gel and kept at 20 ° C for 6 hours.
After adjusting the temperature in a 5% RH environment, mass measurement was performed. <Hygroscopicity> The mass was measured after the temperature and humidity were adjusted for 24 hours in an environment of 20 ° C. and 65% RH, and calculated from the following formula. Moisture absorption rate (%) = {(moisture absorption mass-excess dry mass) / excess dry mass}
× 100

<Heat absorption by moisture absorption> After drying at 110 ° C. for 6 hours,
Cooled in a desiccator containing silica gel to dryness 5
After mounting a temperature sensor (for example, manufactured by Anritsu Keiki Co., Ltd .; 540K MD-5 type) on a measurement sample of cm × 5 cm, 2
A temperature recorder (for example, manufactured by Anritsu Keiki Co., Ltd .; DATA COLLECTOR) for moisture absorption and heat generation under 0 ° C. and 95% RH environment (for example, desiccator containing saturated aqueous solution of potassium sulfate).
AM-7052 type). <Water absorption exothermicity> After attaching a temperature sensor to the 5 cm x 5 cm measurement sample in the absolutely dry state, ion exchanged water equivalent to 50% of the sample mass is uniformly added to 3 to 5 at 20 ° C and 65% RH environment. After spraying for 2 seconds, the water absorption exothermicity was measured with a temperature recorder. The water absorption heat generation time and the water absorption heat generation retention time (minutes) above the maximum water absorption heat generation temperature and the sample temperature before water absorption were evaluated.

<Antibacterial property> A quantitative antibacterial test method (unified test method) of a textile product was used according to the manual.
As the test bacterial species, Staphylococcus aureus Staph-yl
Using Occoccus aureus ATCC 6538P, the number was determined by the following method from the number of unprocessed cloth (standard cotton cloth) bacteria [B] and the number of evaluated sample bacteria [C]. Bacteriostatic activity value = logB-logC Products having a bacteriostatic activity value of 2.2 or more were considered to have antibacterial properties.

The highly hygroscopic / water-absorbing exothermic organic fine particles used in the examples were produced by the following method. Water-soluble polymer 3 of methacrylic acid / sodium p-styrene sulfonate = 70/30
50 parts and 35 parts of sodium sulfate were dissolved in 6500 parts of water and charged into a polymerization tank equipped with a paddle-type stirrer. Next, 15 parts of 2,2'-azobis- (2,4-dimethylvaleronitrile) was dissolved in 2750 parts of methyl acrylate and 330 parts of divinylbenzene and charged into a polymerization tank at 400 rpm.
Polymerization was carried out at 60 ° C. for 2 hours with stirring to obtain a copolymer having a polymerization rate of 88%. 100 parts of the polymer is dispersed in 900 parts of water, 110 parts of caustic soda is added thereto, and 90 ° C.
After reacting for 2.5 hours, the methyl ester portion of methyl acrylate is hydrolyzed to give a carboxyl group 4.6.
A crosslinked polymer having a milliequivalent / g was obtained. The obtained polymer was dispersed in water, washed, dehydrated, and then pulverized, divided or filtered to obtain highly hygroscopic / water-absorbing exothermic particles. The obtained highly hygroscopic / water-absorbing exothermic organic fine particles had a moisture absorption rate of 50% at 20 ° C. and 65% RH, and an average particle diameter of 0.8 μm.

Example 1 Polyester Russell net having a basis weight of 170 g / m ^{2 and} a mesh size of 8 mm × 8 mm was used as a hydrophilic resin binder in 95 parts of an aqueous dispersion containing 20% of the highly hygroscopic / water-absorbing heat-generating fine particles. TF-3500
(Kao hydrophilic hydrophilic binder; solid content 40
%) 5 parts were added to the working fluid, and squeezed with a mangle to obtain a wet pickup rate of 115%.
After drying at 37 ° C for 3 minutes, curing was performed at 170 ° C for 1 minute to obtain a processed net. The basis weight of the obtained processing net is 21
It was 1 g / m ² , and the amount of highly hygroscopic / water-absorbing exothermic particles deposited was 37 g / m ² . As a method for measuring the exothermic effect, a processed net (50 cm ² = 1.05 g) was dried at 110 ° C. for 2 hours to completely remove water, and then stored in a desiccator containing silica gel while preventing moisture absorption. Next, this processed net was taken out from the desiccator and put into a desiccator (95% RH) saturated aqueous solution of potassium sulfate, and temperature rise data was collected by a temperature sensor and a temperature recorder. The temperature sensor used at this time is 540KMD-5 = Anritsu Keiki Co., Ltd., and the temperature recorder is DATA CO- LLECTOR AM-7052 = Anritsu Keiki Co., Ltd.
Is. The measurement environment is 20 ° C. × 65% RH.
The obtained processed net (in a well-dried state) was stretched on a snowfield in the snowfall season, and the snow accretion situation was evaluated by visual observation at the same time as the start of snowfall. Table 1 shows the heat generation effect and snow accretion suppression effect of the obtained processed net. The net had antibacterial properties.

[Example 2] A working net was obtained in the same manner as in Example 1 except that the solid content of the working liquid was 50% of that of Example 1 and the wet pickup rate was 60%. . The amount of highly hygroscopic / water-absorbing exothermic particles adhered to the obtained processed net was 11 g / m ² . The heat generation effect and the snow accretion suppression effect of the processed net were measured in the same manner as in Example 1. The net had antibacterial properties.

[Comparative Example 1] With respect to the unprocessed net used in Example 1, the heat generating effect and the snow accretion suppressing effect were measured in the same manner as in Example 1. The net had antibacterial properties.

Table 1 summarizes the heat generation effect and snow accretion suppression effect of the examples and comparative examples.

[Table 1]

[0034]

EFFECTS OF THE INVENTION According to the present invention, by adhering highly hygroscopic and exothermic fine particles to a knitted fabric, a woven fabric, a string-shaped body or a net-shaped resin molded product through a small amount of a hydrophilic resin, moisture in the external environment (water vapor ) Or moisture (liquid) to generate heat quickly and stably, a suitable snow cover net can be easily obtained.

─────────────────────────────────────────────────── ─── Continuation of front page (51) Int.Cl. ⁷ Identification code FI theme code (reference) D06M 23/08 D06M 23/08 4L048 // E01H 5/10 E01H 5/10 Z F term (reference) 2D026 CL03 4L002 AA07 CB02 DA03 FA06 4L031 AA18 AB33 BA33 4L033 AA07 AB06 AC15 CA13 CA18 4L046 AA24 BB00 4L048 AA21 BA06 DA30 EB00

Claims (9)

[Claims] 1. An n-gonal (n ≧ 3) net-like structure having at least a mesh size and a minimum distance of 2 mm or more, to which highly hygroscopic fine particles are adhered, and the maximum temperature rise during moisture absorption and / or water absorption. Is a snow-covering net that is 3 ° C or higher. 2. The snow cover net according to claim 1, wherein heat generated when absorbing moisture is maintained for 30 minutes or more, and / or heat generated when absorbing water is maintained for 1 minute or more. 3. The snow cover net according to claim 1, wherein the maximum temperature rise during water absorption is 8 ° C. or higher. 4. The snow cover net according to claim 1, wherein the highly hygroscopic particles are organic particles. 5. The highly hygroscopic organic fine particles are polystyrene-based,
Polyacrylonitrile-based, polyacrylic ester-based,
Any vinyl polymer of polymethacrylic acid ester type, having a sulfonic acid group, a carboxylic acid group, a phosphoric acid group, or at least one hydrophilic group of metal salts thereof,
The snow cover net according to claim 4, which is a crosslinked polymer crosslinked with divinylbenzene, triallyl isocyanate or hydrazine. 6. The snow cover net according to claim 1, wherein the highly hygroscopic fine particles have an average particle diameter of less than 2 μm. 7. The highly hygroscopic fine particles are immobilized on the structure via a hydrophilic resin.
The snow cover net described in any one of. 8. The mass ratio of the highly hygroscopic fine particles to the hydrophilic resin is from 1/1 to 20/1.
The snow cover net described in any one of. 9. The net-like structure is a knitted fabric, a woven fabric, a net, a string-like body or a net-like resin molded body composed of natural fibers, synthetic fibers or mixed fibers thereof. 8. The snow cover net according to any one of 8.