JPH04102472A - Method for keeping and reproducing artificial snow - Google Patents

Abstract

PURPOSE:To easily recool and refreeze an artificial snow for ski to make the snow quality suitable for ski again by recooling the snow by using at least one selected from the group consisting of low temperature liquid, low temperature solid and low temperature gas, when the snow quality of the artificial snow using a water absorptive resin in a part or the whole of the material is deteriorated. CONSTITUTION:In a highly water absorptive resin granular body in which the granular form is kept even if water is absorbed, the granules are mutually non-adhesive, the water absorptive capacity to deionized water is about 30-500 time, and the grain diameter before water absorption is about 20-500mum is made to absorb water. The resin is swollen until the grain diameter becomes about 0.05-5mm, or the resulting resin is mixed with natural snow, artificial snow produced by an artificial snowing device, or ice snow obtained by pulverizing ice mass, followed by freezing, whereby an artificial snow is obtained. Thus, a method for keeping and reproducing the artificial snow suitable to the slope of an indoor skiing ground is proposed.

Description

DETAILED DESCRIPTION OF THE INVENTION [Industrial Field of Application] The present invention relates to a method for maintaining and regenerating artificial snow.

More specifically, the present invention relates to a method for maintaining the quality of artificial snow on an artificial ski slope to a level suitable for skiing.

[Prior Art] (Natural Tomi) In recent years, snowfall has been decreasing year by year, causing problems in the opening of ski resorts. Moreover, the natural snow that accumulates on the ground is too soft and difficult to ski on, making it unsuitable for ski slopes as it is, so the snow has to be compacted many times with snow compactors. Also, compacting snow using a snow compactor is not suitable for competitions.
Methods such as ``tsubo-ashi'', where people step on the ground with only their shoes, and methods of sprinkling water on thunderstorms have been adopted. The ski slopes measured in this way are greatly affected by the outside temperature, and the quality of the snow changes over time. This is because sublimation and condensation occur inside the snowpack, and the snow crystals change, progressing from "plum snow" to "rough snow." Rough snow is extremely difficult for skiers to slip on, and therefore, the work of breaking up the snow, that is, blooming, must be performed frequently, but even this cannot be said to be sufficiently effective.

(Artificial Snow) Artificial snow machines have recently been increasingly introduced at ski resorts in the country in order to hasten or extend the skiing season. There are two types of artificial snowmaking devices: gun type and fan type. One of these! ! The method of making snow in a field is to make fine ice by using adiabatic expansion of compressed air with high-pressure water in the atmosphere below 0°C or by using cold air. The artificial snow made in this way contains more than 10% water and has a density of 0.3-0.4 g/am'.
1 strength is less than I Kg/c@", and it is not suitable for skiing unless it is compacted. Also, compared to natural snow, this kind of snow is
The quality of the snow changes rapidly, and in a few days it may progress to coarse snow with an outer diameter of about 1 to 5 mm. As mentioned above, the snow quality in Zarametomi is difficult for skiing, so the same measures as mentioned above are taken.

Artificial snowmaking machines have also been introduced that freeze water into ice cubes and apply physical impact to crush them into ice particles and snowflakes.
This also has the disadvantage that only a snow cone-like or rough snow can be obtained, which is a troublesome snow quality, so the same countermeasures as mentioned above are taken.

An artificial snow manufacturing method has been proposed in which water is mixed with a surfactant, stirred and aerated to form foam, and the foam is frozen to form snow crystals (Japanese Patent Publication No. 2-27584), but the above It is difficult to solve such problems, and the process of using a surfactant or aeration is complicated, resulting in increased costs and pollution problems.

In addition, in the case of artificial snow made by mixing a water-swellable material (water-absorbing resin) with water and freezing it after aeration, as disclosed in Patent Application Publication No. 83-500528,
The density and strength of snow tend to vary depending on aeration conditions and freezing conditions, with a density of 0.4 to 0.9 g/a and a strength of 1
0 to several 100 kg1c-2. Such lightning is more like rough, fine ice or ice burn than snow. If it is in the same state as an ice burn, it must be crushed into ice grains or snowflakes by applying a physical impact as described above, and only a rough snow-like material can be obtained. Therefore, when making artificial snow using only water-swellable materials, in order to make it suitable for skiing, it is necessary to add surfactants and adjust the particle size and water absorption ratio to prevent frozen particles from bonding together more than necessary. g*t, or blooming must be performed frequently. Such snow can be said to be extremely difficult to use at ski resorts.

Additionally, since outdoor ski resorts are dependent on the weather, indoor ski resorts that can be used throughout the year are becoming increasingly popular. Artificial slopes at indoor ski resorts are also constructed by placing the above-mentioned artificial snow, artificial ice particles, snowflakes, etc., or artificial snow made from water-swellable materials (water-absorbing resins) and water on artificial slopes. However, indoor ski resorts built using these methods also have the same problems as above.

In addition, the water-swellable material (water-absorbing resin) and water are mixed on the artificial slope of an indoor ski resort (weight ratio, approximately 1/80 to 1/80).
100) There are also artificial slopes where ice is placed on the surface of the snow, like ice skating salt, and then only the surface is bloomed to scrape off the ice and create artificial snow. In addition to the problems mentioned above, indoor ski resorts built using this method also have other problems, such as the fact that there is a layer of ice underneath the artificial snow, making it difficult for ski poles to stand.

The inventor has developed an artificial snow that can be used as is without using surfactants or aeration, and that can be easily maintained to make the slopes suitable for skiing. Artificial snow made by mixing and freezing natural snow, ice, etc., with or without absorbing water using superabsorbent resin granules, and swells by absorbing water. The above problem can be solved by using artificial snow made by freezing super absorbent resin granules using a coolant such as dry ice or liquefied carbon dioxide.

However, during long-term use or after use, the surface of the artificial snow may melt and become unsuitable for skiing, or there is a risk that it will become unsuitable for skiing. It is desired to develop a method for maintaining and regenerating artificial snow that can be used as a quality material.

[Problem to be solved by the invention] Artificial snow may melt during or after use, and the quality of the snow may no longer be suitable for skiing, or there may be a risk that the snow may become unsuitable for skiing. I want to make the snow suitable for skiing again.

[Means for Solving the Problems] As a result of extensive research by the present inventors in order to solve the conventional problems, the purpose of the present invention is to develop a method for maintaining and regenerating artificial snow suitable for the slopes of indoor ski resorts. This is what we provide.

The invention of claim (1) of the present invention provides that when the quality of artificial snow for skiing using water-absorbing resin in part or all of the material deteriorates, the material becomes a low-temperature liquid, a low-temperature solid, and a low-temperature gas. A method for maintaining and regenerating artificial snow characterized by recooling using at least one selected from the group.

The invention of claim (2) of the present invention provides that the artificial snow maintains its granular shape even after water absorption, is non-adhesive to each other, has a water absorption capacity of about 30 to 500 times that of deionized water, and has a particle size of about 20% before water absorption. ~5
00 μm super absorbent resin granules absorb water and swell until the particle size becomes about 0.05 to 5 μm, or add natural snow, artificial snow made with an artificial snowmaking device, or ice blocks to it. Claim (1) characterized in that it is artificial snow obtained by freezing a mixture of crushed ice and snow.
) is a method for maintaining and regenerating artificial snow.

The invention of claim (3) of the present invention is that the super absorbent resin granules are a saponified product of polyacrylate, a copolymer of vinyl alcohol and acrylate, or a copolymer of isobutylene and maleic anhydride. The artificial snow maintenance and regeneration method according to claim (2), characterized in that:

The artificial snow used in the present invention may be any of the artificial snow described above and is not particularly limited.

However, artificial snow developed by the present inventors, which is made by using super absorbent resin granules to absorb water, or by mixing it with natural snow, ice and snow, etc. and freezing it without absorbing water, Artificial snow is made by freezing superabsorbent resin granules that absorb water and swell using coolants such as refrigerants, dry ice, and liquefied carbonate.
It is preferable to use the artificial snow that has been created because it can be used as is, and the slope can be easily maintained so that it is suitable for skiing.

Examples of the superabsorbent resin include starch-based, cellulose-based, and synthetic resin-based polymers such as acrylamide, acrylic acid, acrylates, methacrylates, styrene, vinyl ether, copolymers, and terpolymers. Particularly suitable are polyacrylates obtained by reverse-phase suspension polymerization in a organic solvent, which exhibit granular form, vinyl alcohol and acrylate copolymers, or saponified copolymers of isobutylene and maleic anhydride. .

The superabsorbent resin has a granular form, and the particle size is approximately 20 to 500 μm before water absorption and approximately 0.05 mm to 5 μm after water absorption.
It is preferable that the thickness be about mm. If the particle size is less than about 20μm before water absorption, it will be too fine and the artificial snow will become too hard.
If it is more than 500 μm, the artificial snow will become rough and undesirable.

The reasons why granular superabsorbent resin is preferable are that it is easy to handle, the artificial snow obtained by freezing becomes granular and the artificial snow becomes smooth like powdered snow, the granular artificial snow makes it easy to ski on, and it is affected by the outside air. It is difficult to melt due to snow, etc., making it easier to maintain ski slopes economically, and it is easy to mix with natural snow.

Even after the superabsorbent resin absorbs water, it remains granular and fluid,
In order to make them non-adhesive to each other, the degree of crosslinking can be increased using polyvalent epoxy or polyvalent amine, but excessive crosslinking will reduce the water absorption capacity, so the amount of crosslinking agent should be adjusted to obtain an appropriate water absorption capacity. Adjust.

The reason why the superabsorbent resin remains granular and fluid even after absorbing water is thought to be because there is little water adhering between the absorbed particles, and the particles slide against each other, creating voids.

Some super absorbent polymers become glue-like when they absorb water, but once they become glue-like, they become one large block of ice when frozen, and unless they are crushed into small pieces, they cannot be used as artificial snow for skiing. This artificial snow is undesirable because, as mentioned above, it is difficult to maintain it in a manner suitable for skiing.

The superabsorbent resin has a water absorption capacity of 30 to 5 for deionized water.
00 times, preferably 50 to 200 times. If the water absorption capacity is less than 30 times, the water absorption capacity of the resulting artificial snow will be low, making it difficult to maintain the desired snow quality by absorbing the liquid water generated when the artificial snow melts. On the other hand, 50
(If it is larger than 1, the gel strength will be weak when water is absorbed, and it will be easy to break when pressure is applied, which is not preferable.

The amount of water absorbed by the super absorbent resin is less than the maximum water retention amount of the super absorbent resin, and the water absorption capacity is about 5 to 100 times. If you want to obtain soft artificial snow, it is preferably about 5 to 50 times as much, and if you want to obtain hard artificial snow, it is preferably about 30 to 100 times.

Since the water absorption is less than the maximum water retention capacity of the super absorbent resin,
Artificial snow made by freezing it still has the ability to absorb water, and can maintain the desired snow quality without changing the desired snow quality by absorbing the liquid water that is generated when the artificial snow melts due to increases in outside temperature, etc. .

For example, if hard and heavy artificial snow is desired, the particle size should be small (20 to 150 μm) and the ratio of water absorption capacity/water absorption capacity should be large (30 to 80%). On the other hand, if you want to obtain soft and light artificial snow, the particle size should be large (150 to 500 μm recommended) and the ratio of water absorption capacity/water absorption capacity should be small (10 to 50%).

Any method can be used to make the super absorbent resin absorb water.
For example, it is sufficient to simply throw the particles into stirred water and leave them for several minutes, depending on the water absorption capacity.

The water absorption rate is affected by the water temperature, and the water absorption rate tends to be slow at low temperatures and faster at higher temperatures. For example, when the water temperature is 10° C. or lower, it is desirable to appropriately heat the water to absorb water.

Even if the superabsorbent resin that has absorbed water is left at room temperature, it will not release moisture and can be kept stable for a long time. (more than 1 month) There are no particular adverse effects.

Since the superabsorbent resin itself is water absorbent, when storing it, it is desirable to store it in a sealed container, for example, to prevent moisture absorption.

There are two methods for freezing superabsorbent resin granules that have absorbed water: one is to make ``smooth artificial snow'' in which the particles are finely and evenly dispersed, and the other is to make ``Rakugan'' sweets, in which the particles are lightly adhered to each other. This is different from the case of making "artificial snow made of snow grains," which is very similar.

When making "smooth artificial snow", the above-mentioned artificial snowmaking machine or snowmaking machine may be used, but it is preferable to use a cooling agent such as dry ice, liquefied carbon dioxide, liquid nitrogen, or liquid air, or a latent heat of vaporization agent. A method is used in which the substance is rapidly frozen while being stirred and mixed in direct contact with the same effective substance using sensible heat.

When making "artificial snow made of snow grains," super absorbent resin granules are placed on a base such as a pipe, sheet, floor, or board that has been cooled with a coolant such as a refrigerant, and then frozen or absorbed. It can be produced by arranging swollen superabsorbent resin particles in a layer to a thickness of about 6 cm or less and freezing in a freezer at -5 to -30°C. The temperature of the base is preferably about -40°C or lower, and the lower the temperature, the harder the artificial snow can be obtained.

``Smooth artificial snow'' and ``snow grain artificial snow'' can be used as is on the slopes. By using it alone without mixing it with natural snow, it is possible to easily create an artificial ski resort, and it is also easy to maintain.

The slopes and flat areas of artificial ski resorts may be made of earth, concrete, metal, wood, plastics, ceramics, etc., and may be provided with insulation and/or cooling and refrigeration systems.

If you want to maintain an artificial ski slope for a long period of time,
Preferably, insulation and/or cooling and refrigeration systems are provided.

When building a ski slope on a slope or flat area like this,
Although "smooth artificial snow" and "snow particle laminated artificial snow" can be used individually, it is preferable to arrange "snow particle laminated artificial snow" on the slopes and flat surfaces mentioned above as root snow, and then By placing ``smooth artificial snow'' on the slopes and configuring them with appropriate thickness, it is possible to create even better slopes that do not have the above-mentioned problems, and also eliminate problems such as the stock not being able to stand up.

According to the method for maintaining and regenerating artificial snow of the present invention, when the quality of the artificial snow deteriorates during or after long-term use, at least one of the following is selected from the group consisting of low-temperature liquid, low-temperature solid, and low-temperature gas. The snow can be re-cooled or re-frozen to maintain and regenerate snow suitable for skiing. Usually, there are many cases where the surface of artificial snow melts and the snow quality is no longer suitable for skiing, and the method of the present invention can be preferably applied to such cases.

Low-temperature liquids that can be used in the present invention include liquefied carbon dioxide, liquid air, liquid nitrogen, etc., low-temperature solids include dry ice, ice, natural snow, artificial snow, etc., and low-temperature gases include air. , nitrogen, carbon dioxide, etc. Furthermore, as the low-temperature gas, solid, or gas that can be used in the present invention, it is also possible to use substances with the same effect other than the above-mentioned substances that utilize latent heat of vaporization or sensible heat. These may be used alone or in combination of two or more.

The above-mentioned "snow quality suitable for skiing" is defined as having a density of approximately 0.63 - 0.8 Kg/c, and a strength of approximately 1.0 kg/c, and a strength of approximately 1 ~10
It was found that the snow had a characteristic of Kg/c-2. However, in the case of the artificial snow used in the present invention, even if the density and strength slightly exceed these ranges, it can still be considered as ``snow quality suitable for skiing'', and in the case of ``smooth artificial snow'', the density and strength may exceed these ranges. If it is within the above range or near it, the strength may not be a problem. Therefore, in order to maintain the artificial snow used in the present invention at a quality suitable for skiing, the density and strength characteristics are maintained within or near the above range. In order to find out whether the snow quality is good or not, a reliable and preferable method is to actually create a slope at an artificial ski resort using artificial snow and judge the glide performance of the ski.

Artificial snow that has melted or is at risk of melting can be recooled or refrozen using low-temperature liquids, solids, or gases such as liquefied carbon dioxide, dry ice, or carbon dioxide gas, either manually or automatically using machines. But that's fine.

Dry ice, liquefied carbon dioxide, etc. may be simply sown, sprayed, sprinkled, or sprayed on the slope, or may be mixed or stirred afterwards. Alternatively, the artificial snow that has melted or is at risk of melting is collected by suction, scraping, conveyor, etc., and is rapidly cooled while stirring and mixing in direct contact with dry ice, liquefied carbon dioxide, low-temperature air, etc.
Alternatively, it may be frozen and then placed again on the slope.

When artificial snow is recooled or refrozen using low-temperature liquids, solids, or gases such as liquefied carbon dioxide, dry ice, or carbon dioxide gas, the temperature, amount used, mixing and stirring time, etc. are not particularly limited. The temperature of recooled and refrozen artificial snow is approximately 0 to -
It is preferable to set the temperature to 30° C., but this will vary depending on various conditions, so it is best to select it as appropriate.

The superabsorbent resin particles used in the present invention can be separated and recovered by an appropriate method, dried, etc., and reused.

The superabsorbent resin granules used in the present invention are themselves photodegradable and biodegradable, so there is no problem in disposing of them after use. Known accelerators, catalysts, additives, etc. for photodegradation and biodegradation may be blended, added, impregnated, or applied to the superabsorbent resin. Since the superabsorbent resin itself is safe for the human body, these additives are also preferably selected with safety in mind.

The artificial snow and/or superabsorbent resin used in the present invention may be colored by a known method using pigments, dyes, etc. Colored artificial snow is beautiful and can add new commercial value. For example, it can be used to distinguish ski slopes for advanced skiers, slopes for beginners, etc. by color, making skiing more enjoyable.

New commercial value can be added to the artificial snow and/or superabsorbent resin used in the present invention by scenting the artificial snow and/or the superabsorbent resin with a known perfume, aromatic agent, fragrance, or the like.

Adding antioxidants, ultraviolet absorbers, fluorescent agents, nucleating agents, fillers, substances with a low coefficient of friction, and other additives to the superabsorbent resin used in the present invention within a range that does not impair the gist of the present invention; It may be blended, applied, or impregnated.

[Example] Next, the present invention will be specifically explained with reference to Examples, but the present invention is not limited to these Examples.

In addition, the water absorption capacity, fluidity, density and strength of artificial snow after freezing in the following examples are determined by the following operations.

(Water absorption capacity for deionized water) Disperse 0.5 g of dry polymer in 11 deionized water,
After being allowed to stand for 4 hours, the resulting polymer was filtered through a 60-mesh wire mesh, and the resulting water-swelled weight (W) was measured, and this value was divided by the initial dry polymer weight (W).

(Fluidity after water absorption) After adding 50 cc of deionized water to 1.0 g of dry polymer and absorbing all the water, the water-swollen body was observed without moving.

(Density of artificial snow after freezing) Remove snow whose volume is known, weigh it, and divide the weight by the volume. The unit is g/cyx3°.When the snow is soft, inserting a thin stainless steel box with a known internal volume into the snow will remove the snow with a known volume. In case of hard snow,
Cut the lightning into squares with a saw, measure the dimensions with a ruler, and calculate the volume.

(Strength of artificial snow after freezing) Using a Kinoshita hardness tester, drop a weight onto the artificial snow and measure the strength of the fall. The unit is kg/c■2°. Replace the adapter so that the sinking of the 2° disc into the artificial snow is between 7 and 30■■, and calculate the strength from the conversion table.

(Example of synthesis of super absorbent resin granules) 150 g of deionized water was charged into a 5001 separable flask equipped with a stirrer, reflux condenser, dropping funnel, thermometer and nitrogen gas inlet tube, and partially saponified polyvinyl was added as a dispersant. Alcohol (0H-23 manufactured by Nippon Gosei Kagaku ■) 0.2g
was added, heated and melted, and then replaced with nitrogen.

Meanwhile, in advance in an Erlenmeyer flask, prepare lauryl acrylate and tridecyl mixed ester (Osaka Organic (1 ■ IILT)
22.5g1 Hydroxyethyl methacrylate10.
0g of azobisdimethylvaleronitrile was added to 17.5g of methyl methacrylate and dissolved therein, and the solution was added dropwise to the above separable flask over 1 hour under nitrogen bubbling. Hold at 65°C for 5 hours to complete the reaction,
After cooling, the solid matter was filtered, washed with water, and dried under reduced pressure to obtain a bead-cane dispersant.

In a 1000 sl separable flask equipped with a stirrer, reflux condenser, dropping funnel, thermometer and nitrogen gas inlet tube
360.7 g of hexane and 4.32 g of the above dispersant were charged, heated to 50° C. to disperse and dissolve, and then replaced with nitrogen.

Meanwhile, 72% of acrylic acid was prepared in advance in an Erlenmeyer flask.
0 g was partially neutralized with 32.2 g of sodium hydroxide dissolved in 103.6 g of deionized water, and further 0.24 g of potassium persulfate was dissolved at room temperature. This aqueous monomer solution was added dropwise to the above separable flask over 1 hour under nitrogen bubbling at a stirring speed of 300 rpm, and after refluxing for 2 hours, 0°Ig of 30% hydrogen peroxide was added, and the mixture was further refluxed. The polymerization was continued for 1 hour to complete the polymerization. Thereafter, 0.73 g of ethylene glycol diglycidyl ether was added, followed by azeotropic deicing, filtration, and drying under reduced pressure to obtain white superabsorbent resin particles.

This super absorbent resin granule has an average particle size of 100 μm and exhibits excellent fluidity.

When left in water at room temperature for 19 seconds while stirring, it absorbed 50 times more water and swelled, with an average particle size of 0.4 mm, which also showed excellent fluidity. The swollen superabsorbent resin granules were left at room temperature for 60 days or more after being absorbed 50 times, but were able to be stably maintained without watering.

The water absorption capacity was 100 times higher than that of deionized water.

- The above-mentioned super water-absorbent resin granules that have been swollen by absorbing 50 times water or 5
100 parts by weight of a mixture (25/75 weight ratio) of super absorbent resin granules swollen by absorbing 0 times water and 100 parts by weight of liquefied carbonic acid
parts by weight were mixed for about 1 minute at room temperature of -8.3°C using a container with a mixer (Hitachi hand mixer HF-330) and frozen. We created soft artificial snow at a temperature of -30℃.

゛: The above-mentioned super absorbent resin granules (temperature: 19°C), which have been swollen by absorbing 50 times the water, are placed in a wooden case (width 20 cm, length 30 cm,
The snow grains were placed in a cup at a depth of 3 am and frozen for about 1 to 2 hours in a -30°C freezer to produce artificial snow. The artificial snow made of snow particles is block-shaped and has a width of about 20C11
1 length about 30 am 1 thickness about 3°3c11, density 0
, 34 Kg/cm", and the strength was about 4 Kg/cm2.

S　−　゛Lente　　.

Artificial wooden ski slope (width approx. 40 cm, slope angle approx. 10°) lined with styrofoam (approx. 3 cm thick)
Approximately 20 kg of dry ice chips were sown on top of the slope (consisting of a slope section with a length of about 4 m and a continuous horizontal section with a length of about 2 N), and on top of that, the artificial snow blocks made of snow particles were placed on the entire surface. It was set up and covered with snow.

A ski slope was created by spreading the above-mentioned smooth artificial snow to a thickness of approximately 4 cm over the above-mentioned root snow.

Outside temperature of about 21℃, artificial snow temperature -10 to -30℃
We investigated the glide properties of skis. As a result, it had excellent glide, created spurts on the slopes, and had roughly the same acceleration as natural powder snow.

Even if the temperature of the artificial snow varied from about -10°C to -30°C, or even if the top layer of artificial snow melted to some extent and turned into gel, the sliding properties were excellent. I couldn't climb the slopes without using ski poles. The stock stuck easily to the ski slope. The edge of the ski was easy to hit. It also made a nice squeaking sound when I stepped on it with my skis.

After long-term use, when the temperature of the artificial snow surface reaches 0℃,
When we collected the snow and brought it into contact with a sufficient amount of carbon dioxide gas at about -25°C to bring the temperature of the artificial snow to about -20°C, we were able to get good powder snow again, so we redistributed it on the slopes. Established.

After a long period of use, when the artificial snow surface slightly melted and turned into a gel, approximately 5 kg of granular dry ice was sown on the slope.
By mixing it lightly, I was able to get it into a nice powdery snow condition again.

In addition, after a long period of use, when the artificial snow surface melts a little and becomes a gel, collect the surface and mix it with about 8 kg of liquefied carbon dioxide for about 1 minute, stir and freeze it, and it will become compacted again. I was able to do so, so I relocated it to the ski slope.

Furthermore, after a long period of use, when the artificial snow surface had slightly melted into a gel, about 3 kg of liquid air was sprayed on it and mixed lightly, making it possible to obtain good powder snow again.

Furthermore, after a long period of use, when the artificial snow surface slightly melted into a gel, about 3 kg of liquid nitrogen was sprinkled on it and mixed lightly, making it possible to re-form it into compact powder snow.

Furthermore, after a long period of use, when the surface of the artificial snow melts a little and becomes a gel, sprinkle about 3 kg of granular dry ice and about 2 kg of liquefied carbon dioxide, and mix it lightly to make it into a compact powder snow again. was completed.

These slopes have excellent sliding properties and skied well.

By repeating this operation in this way, it was possible to maintain snow quality suitable for skiing on this slope for a long period of time.

[Effects of the Invention] The present invention provides a method for maintaining and regenerating the snow quality of artificial snow on an artificial ski slope, particularly an indoor ski slope, to a snow quality suitable for skiing over a long period of time.

If the surface of the artificial snow deteriorates during or after use due to melting, and the quality of the snow is no longer suitable for skiing, or there is a risk that it will become unsuitable for skiing, use dry ice, liquefied carbon dioxide, liquid air, liquid nitrogen, To provide a method for maintaining and regenerating artificial snow that can be easily made into a snow quality suitable for skiing by recooling and refreezing using low-temperature air, low-temperature carbon dioxide, etc.

The artificial snow of the present invention is applied to slopes of artificial ski resorts equipped with artificial snow made by freezing super absorbent resin granules that absorb water and swell with dry ice, liquefied carbon dioxide, etc., or by freezing them in a freezer. If you use the maintenance and regeneration method, you can easily
Moreover, it is possible to maintain snow quality suitable for skiing for a long period of time at low cost.

Claims (3)

[Claims] (1) When the quality of artificial snow for skiing that uses water-absorbing resin as part or all of the material deteriorates, use at least one selected from the group consisting of low-temperature liquid, low-temperature solid, and low-temperature gas. A method for maintaining and regenerating artificial snow, characterized by recooling it. (2) Artificial snow is a super water-absorbing resin granule that maintains its granular shape even when it absorbs water, is non-adhesive to each other, has a water absorption capacity of approximately 30 to 500 times that of deionized water, and has a particle size of approximately 20 to 500 μm before absorbing water. When the body absorbs water, the particle size is approximately 0.05 to 5 mm.
or natural snow,
The method for maintaining and regenerating artificial snow according to claim 1, wherein the artificial snow is obtained by freezing artificial snow made by an artificial snow-making device or by freezing a mixture of crushed ice and snow. (3) Claim (2) characterized in that the super absorbent resin granules are a saponified product of polyacrylate, a copolymer of vinyl alcohol and acrylate, or a copolymer of isobutylene and maleic anhydride. How to maintain and regenerate artificial snow as described.