JPH0791476B2 - Snow composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a snow composition.

More specifically, the present invention relates to obtaining a snow composition suitable for skis, by freely controlling the snow quality by mixing granular snow-absorbing resin with natural snow, artificial snow, or ice snow.

[Prior art] (Natural snow) In recent years, the amount of snowfall has decreased year by year, which has hindered the opening of ski areas. Moreover, the natural snow on the ground is too soft and the skis are not slippery. As it is, it is not suitable as a slope, so you have to compress the snow many times with a snow plow. In addition, compression with a snow crusher is not suitable for competition,
The methods used are "pots" that people step on with their shoes and a method of spraying water on snow. The slope made up in this way is greatly affected by the temperature of the outside air, and the quality of snow changes with the passage of time. This is because sublimation / condensation occurs inside the snow cover and the change of the snow crystals progresses. Rough snow is very slippery snow for skiers, and therefore, the work of breaking the snow, that is, grooming must be frequently performed, but it is still not sufficiently effective.

(Artificial snow) Recently, artificial snowfall devices have been actively introduced even at ski resorts in Japan in order to accelerate or extend the gliding season. There are roughly two types of artificial snowfall devices, a gun type and a fan type. The method of making snow with these devices is a method of making fine ice by using adiabatic expansion of compressed air of high-pressure water in the atmosphere at 0 ° C. or lower, or by using cold air. The artificial snow thus produced contains 10% or more of water, has a density of 0.3 to 0.4 g / cm ³ , and a strength of 1 kg / cm ^2.
Below, it is not suitable for skiing without pressure snow. In addition, compared with natural snow, such snow has a rapid change in snow quality, and after several days, it may progress to rough snow with an outer diameter of approximately 1 to 5 mm. As described above, rough snow is a troublesome snow quality for skis, and the same measures as those described above are taken.

In addition, in the case of artificial snow made by mixing (absorbing water) a water-swelling material (water-absorbent resin) and aerating and then freezing as disclosed in Japanese Patent Application Publication No. 63-500526, snow Density and strength tend to vary depending on aeration and freezing conditions, with a density of 0.4 to 0.9 g / cm ³ and a strength of 10 to several 100 kg / cm ² . Rather than snow, such snow is more like lumpy ice or ice burn. Therefore, when making artificial snow only with water-swellable materials, in order to make it suitable for skiing, add a surfactant or adjust the particle size and water absorption ratio so that frozen particles do not combine more than necessary. And grooming must be done frequently. It can be said that such snow is very difficult for ski resorts to use.

[Problems to be Solved by the Invention] Various types of snow such as natural snow and artificial snow have the following problems.

If you don't squeeze in snow, you won't be able to get a good ski slope.

You can't get snow of any density or intensity. In other words,
It is not easy to make snow according to the skier's level and taste.

It is difficult to maintain the condition of the slope because the snow quality changes significantly over time.

In the early spring, the snow will turn into snow and become a slope that is not suitable for skiing.

[Means for Solving the Problem] The inventors of the present invention have conducted extensive studies to solve the conventional problems, and as a result, by mixing the highly water-absorbent resin granules with the snow, snow having an arbitrary density and strength can be obtained. The present invention has resulted in a snow composition which can be obtained and whose snow quality can be prevented from changing with time, and which can be easily and inexpensively manufactured and maintained on a slope preferred by skiers.

According to the present invention, 100 parts by weight of snow selected from natural snow, artificial snow made by an artificial snowfall device and ice snow obtained by crushing ice blocks into fine powder, and high water absorption with a particle size of 20 to 500 μm before water absorption Provided is a snow composition, which is characterized by comprising a mixture with 0.1 to 10.0 parts by weight of a granular resinous material.

The super absorbent polymer particles used in the present invention are commercially available starch-polyacrylate, polyacrylate obtained by reverse phase suspension polymerization in an organic solvent, and polyacrylic acid obtained by stationary aqueous solution polymerization. Examples thereof include salts, saponified products of vinyl alcohol and acrylate copolymers, copolymers of isobutylene and maleic anhydride, and the like. Polyacryl obtained by reverse-phase suspension polymerization in an organic solvent showing a spherical shape. A saponified product, a saponified product of a vinyl alcohol / acrylic acid salt copolymer or an isobutylene / maleic anhydride copolymer is preferable.

The reason why the spherical super absorbent polymer particles are preferable is that they are easily mixed uniformly with snow, that the "ice bridges" between the particles are finely and uniformly dispersed and do not become too hard after freezing. Even if it is exposed to the surface, it is granular and does not deteriorate the slippage.

Furthermore, the super absorbent polymer granules of the present invention are
Granules of 0.05 mm to 2 mm are preferable for uniform mixing with snow, and as a result, 20 to 500 μm is suitable before absorbing water. If it is less than 20 μm, it is too fine and it is difficult to uniformly mix with snow. If it is more than 500 μm, it is not preferable because it is scattered in the snow.

The highly water-absorbent resin granules used in the present invention have a water absorption capacity of 30 to 500 times, preferably 50 to 200 times, for ion-exchanged water. If the water absorption capacity is less than 30 times, it is not economical because a large amount is required for snow. If it is more than 500 times, the gel strength when absorbing water is weak and it is easily broken when pressure is applied, which is not preferable. Further, when absorbing water, it is preferable that it does not form a paste and remains granular and shows fluidity. When it becomes a paste, it becomes one big ice block when frozen and cannot be used as a ski slope unless it is crushed into small pieces. To avoid this, there is a method of atomizing before freezing, but it is not an economical snow quality improvement method because it requires a lot of power because of its high viscosity. In order to keep the fluidity in a granular state even after absorbing water, it is sufficient to increase the degree of crosslinking with a polyvalent epoxy or a polyvalent amine, but if the crosslinking is excessive, the water absorbing ability will decrease, so that the above water absorbing ability is obtained. Adjust the amount of crosslinker.

For mixing the superabsorbent resin particles of the present invention with snow, for example, the following methods are available.

The highly water-absorbent resin granules of the present invention are preliminarily made to absorb water 5 to 100 times, and then uniformly mixed with snow.

The highly water-absorbent resin granules of the present invention are uniformly mixed with snow without absorbing water in advance.

The method of mixing after absorbing water is mainly used to obtain snow of arbitrary density and strength. For 100 parts by weight of snow, 0.1 to 10.0 parts by weight of super absorbent polymer granules (non-absorbed water) is taken to absorb water 5 to 100 times as much as the water swelling body after absorption does not exceed 200 parts by weight, and then uniform with snow To mix. The mixed snow composition freezes due to the latent heat of the snow and the outside air, but at that time, water seeps out from the inside of the water swelling body and the water freezes on the surface of the material, creating a "ice bridge" with the surrounding snow. It was confirmed by microscopic observation of the slice. Therefore, in order to obtain snow of any density and strength, the "ice bridge" may be adjusted, and the amount of water supplied from the water swollen body may be controlled. That is, it is possible to control the amount of water supplied from the water-swelled body by arbitrarily moving parameters such as the particle diameter of the highly water-absorbent resin particles, the ratio of water absorption capacity / water absorption capacity, and the amount of water-swelled body.
As a result, snow of any density and strength can be obtained.
For example, if you want to obtain hard and heavy snow quality, the particle size is small (20 to 150 μm) and the ratio of water absorption capacity / water absorption capacity is large (3
0-80%), increase the amount of water swelling body (30-200 parts by weight).
On the other hand, if you want to get soft and light snow, the particle size is large (150-5
00 μm), a small ratio of water absorption capacity / water absorption capacity (10 to 50%), and a small amount of water swelling body (10 to 80 parts by weight). Further, since these water swelling bodies have a water absorption capacity lower than the water absorption capacity of the super absorbent polymer granules, they absorb the liquid water generated due to the increase in the outside air temperature and maintain the snow quality of the target conditions not to change. be able to.

The method of mixing without absorbing water is mainly used to suppress deterioration of snow quality. For 100 parts by weight of snow,
Super absorbent polymer granules (non-absorbed water) 0.1 to 10.0 parts by weight are mixed. Generally, the amount of snow immediately after being made by an artificial snowfall device is about 60-
A mixture of 90% ice particles and about 40 to 10% liquid water, such wet snow is not slippery for beginners and intermediate skiers. Mixing such water-absorbent resin granules against such snow absorbs unfrozen water and improves the wet snow condition to a dry condition, making it a slope preferred by beginners and intermediate skiers.

Also, in the early winter or early spring when the outside air temperature rises and water (liquid phase) is generated due to snow melting, the deterioration of the snow quality can be suppressed by mixing the super absorbent polymer granules.

The ratio of super absorbent polymer granules to 100 parts by weight of snow is 0.1-
10.0 parts by weight, but large mixing ratio (1.0 to 10.0 parts by weight) especially for damp snow, 0.1 to 0.1% for slightly damp snow
Addition of 1.0 part by weight is preferred.

The method for mixing the superabsorbent resin granules with snow is a container with a device for supplying the superabsorbent resin granules that have not yet absorbed water or the water swelling body that has been previously absorbed to a predetermined water absorption ratio to the material. There is a method in which the container is loaded on a vehicle for slope maintenance, and the materials are sprayed from a supply device and mixed in parallel with the slope maintenance. This method can be used for natural snow, artificial snow and ice.

As another method, a device for directly spraying the superabsorbent resin granules with compressed air to a gun type or fan type artificial snowfall device is attached, and at the same time the superabsorbent resin granules are produced while making artificial snow. There is a method of spraying and mixing.

As another method, there is a method in which, in an artificial snowfall device, the highly water-absorbent resin particles that have been pneumatically transported are mixed with water to absorb water, and the water swelling body is sprayed into the atmosphere by compressed air. At this time, since the artificial snow is simultaneously produced in the artificial snowfall device, it can be mixed.

EXAMPLES Next, the present invention will be specifically described by way of examples, but the present invention is not limited to these examples.

The water absorption capacity, fluidity, and density and strength of the snow composition after freezing in the following Examples and Comparative Examples are determined by the following operations.

(Water absorption capacity for ion-exchanged water) 0.5 g of dried polymer was dispersed in 1 ion-exchanged water, allowed to stand for 24 hours, and then filtered through a 60-mesh wire net to measure the weight (W) of the water swelling body. It is the value obtained by dividing the value by the initial dry polymer (W ₀ ).

(Fluidity after water absorption) After adding 50 cc of ion-exchanged water to 1.0 g of dry polymer to absorb water completely, observe the water swelling body while moving and check the fluidity ○,
It was shown by x and Δ.

(Density of snow composition after freezing) The snow of which the volume is known is taken out, weighed, and the weight is divided by the volume. The unit is g / cm ³ . When the snow is soft, a thin stainless steel box with a known internal volume can be inserted into the snow to remove the snow with a known volume. In the case of hard snow, cut the snow into squares with a saw and measure the dimensions with a ruler to calculate the volume.

(Strength of Snow Composition After Freezing) With a Kinoshita hardness meter, a weight is dropped onto the snow composition and the drop strength is measured. The unit is kg / cm ² . Replace the adapter so that the sinking of the disk into the snow composition is 7 to 30 mm, and calculate the strength from the conversion table.

Example 1 (Type of super absorbent polymer granules) The super absorbent polymer granules were made to absorb 50 times of water to form a water swelling body, and the weight ratio to ice snow (16 mesh) made by crushing ice.
The mixture was mixed at a ratio of 33: 100 and frozen at -5 ° C.

After 16 hours from the mixing, the density and strength of the snow composition were measured and shown in Table-1.

Generally, the skier's slippery strength is about the same for beginners.
1.0kg / cm ² , as it progresses, it will move to harder snow, and if you become an Olympic athlete, you need about 10kg / cm ² of hard snow. However, the hard snow that exceeds it is disliked by both amateur skiers and professional skiers, and the probability of injury when falling is extremely high.

Example 2 (Particle size of super absorbent polymer granules) A snow composition was prepared in the same manner as in Example 1 except that the particle size of super absorbent polymer granules was changed, and the density and strength were measured. -2.

Example 3 (Water absorption capacity of super absorbent polymer granules) A snow composition was prepared in the same manner as in Example 1 except that the water absorption capacity of the super absorbent polymer granules was changed, and its density and strength were measured.
The results are shown in Table-3.

Example 4 (Ratio of water-swelled body) A snow composition was prepared in the same manner as in Example 1 except that the weight ratio of the water-swelled body and ice and snow was changed, and the density and strength were measured.
Shown in FIG.

Example 5 (Slope test) (Teine ski area) A slope of 3 m in width, 15 m in length, and 15 cm in depth was installed, and natural snow 1
A uniform mixture of 00 parts by weight and 33 parts by weight of a water-swelling body in which BL-151 was absorbed 50 times was spread on a slope, and from -5 to-
After being left for 14 hours under an outside temperature of 12 ° C., the density, strength and ski gliding property of the snow composition were examined. The results are shown in Table-5.

Example 6 (Unabsorbed water-absorbent resin granules) Ice-snow (16 mesh pass) made by crushing ice was mixed with unabsorbed water-absorbent resin granules and stored at -1 ° C to obtain density and strength. Was measured over time. The results are shown in Table-6.

[Effect of the Invention] The snow composition of the present invention has an arbitrary density and strength,
Provide ski slopes according to the skier's level and taste. It also has the effect of suppressing changes in snow quality over time, helping to maintain the condition of the slopes. Especially, it has an effective suppression effect against changes to "rough snow" due to changes in the outside temperature and rapid changes in the quality of artificial snow made by artificial snowfall devices, and to maintain a ski-friendly slope for a long period of time. You can

 ─────────────────────────────────────────────────── ─── Continuation of front page (71) Applicant 999999999 Sanyo Denki Co., Ltd. 2-5-5 Keihan Hondori, Moriguchi City, Osaka Prefecture (72) Inventor Yuichiro Miura 18-34, Minami 16jo Nishi, Chuo-ku, Sapporo-shi, Hokkaido ― 12 (72) Inventor Kazuo Hirano 5-20-9 Kamisagimiya, Nakano-ku, Tokyo (72) Inventor Taiji Uebayashi 6-4 Kuranomiyacho, Yamatotakada City, Nara Prefecture (72) Innovator Takayuki Yokohama, Kanagawa Prefecture 2-13-8 Shinoharakita, Kohoku-ku, Yokohama (72) Inventor Shungo Nagai 2-18 Keihan Hondori, Moriguchi City, Osaka Prefecture Sanyo Electric Co., Ltd. (72) Masahisa Otsuka 2-18 Keihan Hondori, Moriguchi City, Osaka Prefecture Address Sanyo Electric Co., Ltd. (56) Reference Japanese Patent Laid-Open No. 63-251502 (JP, A) Special Table 63-500526 (JP, A)

Claims (6)

[Claims] Claims: 1. 100 parts by weight of snow selected from natural snow, artificial snow made by artificial snowfall device and ice snow obtained by crushing ice blocks into fine powder, and high water absorption with a particle size of 20 to 500 μm before water absorption. A snow composition comprising a mixture with 0.1 to 10.0 parts by weight of a resin granular material. 2. The snow composition according to claim 1, wherein the superabsorbent resin particles have a water absorption capacity of 30 to 500 times that of ion-exchanged water. 3. The snow according to claim 1, wherein the super absorbent polymer particles are a saponified product of a polyacrylic acid salt, a vinyl alcohol / acrylic acid salt copolymer, or an isobutylene / maleic anhydride copolymer. Composition. 4. The water-absorbent resin granules are preliminarily 5-100.
The snow composition according to claim 1, wherein water is absorbed twice. 5. The snow composition according to claim 1, wherein the highly water-absorbent resin particles have not been previously absorbed with water. 6. The snow composition according to claim 1, wherein the super absorbent polymer particles are spherical.