JP2007254241A - Silicon-containing inorganic composition, snow melting/antiicing agent, snow melting/antiicing member and circulation liquid - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a silicon-containing inorganic composition having excellent antifreezing effect and cooling storage effect, and a snow melting/antiicing agent, a snow melting/antiicing member and a circulation liquid using the composition. <P>SOLUTION: The silicon-containing inorganic composition is obtained by reacting, in water, (1) metal silicon, (2) at least one selected from the group consisting of fluorides, phosphorous acid, phosphites, nitrous acid, nitrites, carbonic acid, carbonates, 1-10C carboxylic acid, 1-10C carboxylates and inositol, and (3) an alkali metal hydroxide, and has a freezing point of 0 to -80°C. The snow melting/antiicing agent, the snow melting/antiicing member and the circulation liquid contain the silicon-containing inorganic composition. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a silicon-containing inorganic composition useful as a snow melting / freezing preventing agent, a circulating fluid, and the like, as well as a snow melting / freezing preventing agent, a snow melting / freezing preventing member, and a circulating fluid using the composition.

  Although air-conditioning equipment is a necessity in today's cultural life, many antifreezes used for this have pollution problems. For example, Freon has a problem of global warming, and ethylene glycol has a problem of disposal. In addition, there is a risk of contaminating the environment when it collapses and leaks due to an earthquake.

  As a circulating liquid using solar heat, aqueous solutions of potassium formate and potassium acetate are known as inorganic aqueous solutions having fluidity at −20 ° C. to −40 ° C. These aqueous solutions corrode metals. There is a problem that it cannot be used at an extremely low temperature of −40 ° C. or lower.

  As snow melting / freezing preventing agents, chlorides such as sodium chloride and calcium chloride using freezing point depression are widely used. However, the use of these chlorides has a problem of deteriorating the useful life of the roadside concrete structure and causing the trees to die.

  Therefore, it can be used safely at a lower temperature, and there is no problem of pollution, such as snow melting and anti-icing agents, and even if it collapses and leaks due to an earthquake, it may contaminate the environment or cause a fire There is a need for a circulating fluid that can be used for both low temperature and high temperature.

  In relation to the present invention, Patent Document 1 has an excellent antifreeze effect and cold storage effect by appropriately mixing glycerin or trehalose with the aqueous film-forming inorganic compounds described in Patent Documents 2 to 4. It is described that a composition is obtained.

Japanese Patent Laid-Open No. 2000-192024 Patent No. 2015694 Patent No. 2028203 JP-A-8-73212

  The present invention has been made in view of the above-described prior art, and includes a silicon-containing inorganic composition having an excellent antifreeze effect and a cold storage effect, a snow melting / freezing preventing agent and a snow melting / freezing prevention using the composition. It is an object to provide a member and a circulating fluid.

  As a result of intensive studies to solve the above problems, the present inventors have made improvements to the aqueous film-forming inorganic compounds described in Patent Documents 2 to 4, so that the freezing point can be obtained without mixing glycerin or trehalose. It was found that a silicon-containing inorganic composition having an antifreeze effect and a cold storage effect can be obtained. Further, since this composition has an excellent antifreezing effect and a cold storage effect, it was found useful as a raw material for a snow melting / freezing preventing agent, a snow melting / freezing preventing member, and a circulating fluid, and the present invention was completed. It was.

That is, the present invention firstly (1) metallic silicon, (2) fluoride, phosphorous acid, phosphite, nitrous acid, nitrite, carbonic acid, carbonate, carboxylic acid having 1 to 10 carbon atoms, A silicon-containing inorganic composition obtained by reacting at least one selected from the group consisting of a carboxylate having 1 to 10 carbon atoms and inosit and (3) an alkali metal hydroxide in water, and having a freezing point of 0 There is provided a silicon-containing inorganic composition characterized in that the temperature is from ℃ to -80 ℃.
The silicon-containing inorganic composition of the present invention preferably has a longitudinal wave velocity from 20 ° C. to the solidification start point in the range of 1500 to 2300 m / s by an ultrasonic method with a frequency of 5 Hz, and is heated to 120 ° C. Even if it does not become powdery, it is preferable.

Secondly, the present invention provides a snow melting / freezing preventing agent containing the silicon-containing inorganic composition of the present invention.
Thirdly, the present invention provides a snow melting / freezing preventing member obtained by coating, impregnating or baking the silicon-containing inorganic composition of the present invention on the surface of the member.
4thly this invention provides the circulating liquid characterized by containing the silicon-containing inorganic composition of this invention, and being able to circulate at -50 degreeC-+100 degreeC.

  The silicon-containing inorganic composition of the present invention has a freezing point of 0 ° C. to −80 ° C., and has an excellent antifreeze effect and cold storage effect. The composition of the present invention is useful as a raw material for a snow melting / freezing preventing agent, a snow melting / freezing preventing member, and a circulating liquid.

The snow melting / freezing preventing agent and the snow melting / freezing preventing member of the present invention have both an excellent snow melting effect and an anti-icing effect.
Since the snow melting / freezing preventing agent and the snow melting / freezing preventing member of the present invention use the composition of the present invention which is an aqueous solution of an inorganic polymer compound, there is no risk of soil contamination, air pollution, or fire.

  The circulating fluid of the present invention can be used in a wide temperature range from -50 ° C to + 100 ° C. Since the circulating fluid of the present invention uses the composition of the present invention, which is an aqueous solution of an inorganic polymer compound, there is no risk of soil contamination or air pollution even when the circulating fluid collapses and leaks.

Hereinafter, the present invention will be described in detail.
1) Silicon-containing inorganic composition The silicon-containing inorganic composition of the present invention (hereinafter sometimes referred to as “the composition of the present invention”) is (1) metallic silicon, (2) fluoride, phosphorous acid, phosphorous acid. At least one selected from the group consisting of a salt, nitrous acid, nitrite, carbonic acid, carbonate, carboxylic acid having 1 to 10 carbon atoms, carboxylate having 1 to 10 carbon atoms, and inosit (hereinafter referred to as “mineral acids”) And (3) a silicon-containing inorganic composition obtained by reacting an alkali metal hydroxide in water, characterized by having a freezing point of 0 ° C. to −80 ° C.

  The metal silicon used in the present invention is usually one having a purity of 85% by weight or more, preferably 90% by weight or more, more preferably 95% by weight or more. Metallic silicon may be in the form of lumps, granules or powders.

  The mineral minerals used in the present invention are fluorides such as sodium fluoride, potassium fluoride, cesium fluoride, magnesium fluoride, ammonium fluoride; phosphorous acid; sodium phosphite, potassium phosphite, phosphorous acid Phosphites such as ammonium; nitrites; nitrites such as sodium nitrite and potassium nitrite; carbonates; carbonates such as lithium carbonate, sodium carbonate, potassium carbonate, magnesium carbonate and calcium carbonate; formic acid, acetic acid, propionic acid, C1-C10 carboxylic acid such as lactic acid, malonic acid, citric acid, ascorbic acid; C1-C10 carboxylic acid such as lithium salt, sodium salt, potassium salt, magnesium salt, calcium salt, etc. 10 carboxylates; and one or more selected from the group consisting of inosit.

  Among these, in the present invention, since a silicon compound-containing aqueous solution having a lower freezing point is obtained, as the mineral minerals, (a) fluoride, phosphite, nitrite, carbonate, and carbon number 1 to Either a combination of two or more selected from the group consisting of 10 carboxylates, or (b) a carboxylic acid having 1 to 10 carbon atoms is preferred.

  Examples of the alkali metal hydroxide used in the present invention include lithium hydroxide, sodium hydroxide, potassium hydroxide and the like, and sodium hydroxide or potassium hydroxide is preferably used.

  In the composition of the present invention, a large stoichiometric excess of metal silicon is placed in an aqueous solvent, and a predetermined amount of a mineral acid, then an alkali metal hydroxide, or a predetermined amount of a mineral acid and It can be obtained by adding and reacting a mixture with an alkali metal hydroxide.

  Here, “a large stoichiometric excess” means an amount of metal in which unreacted metal silicon remains in the reaction solution even after the reaction between metal silicon and alkali metal hydroxide is completed. This means that silicon is added. Usually, the metal silicon is used in an amount of 6-fold mol or more, preferably 10-fold mol or more based on the alkali metal hydroxide.

  Moreover, the addition amount of an alkali metal hydroxide is 3 times or more of a mineral mineral, Preferably it is 3-10 times amount, More preferably, it is 3-5 times amount on a weight basis.

The reaction temperature is usually 20 to 90 ° C., preferably 30 to 70 ° C., and the reaction time is usually several hours to several tens of hours.
This reaction can be performed with stirring, but can also be performed as it is without stirring.

  The composition of the present invention obtained as described above is an alkaline aqueous solution. The pH is usually 11-14, preferably 12-13. The above-mentioned range by changing the addition ratio of the mineral acid and the alkali metal hydroxide within a range of (mineral acid) :( alkali metal hydroxide) = 1: 3 to 1:10 by weight ratio An aqueous solution having a predetermined pH value can be obtained.

  Although the details of the silicon compound contained in the composition of the present invention are unknown, it is presumed that it is an aqueous solution of a silicon compound having a composition similar to a mixture composed of a silanol salt and siloxane from analysis of IR spectrum and the like.

The composition of the present invention has a freezing point of 0 ° C to -80 ° C, preferably -20 ° C to -60 ° C.
The freezing point is a temperature at which a liquid phase substance maintains equilibrium with a solid phase under a certain pressure, and specifically, a glass transition freezing point. The freezing point can be measured by scanning differential calorimetry (DSC).

  In the composition of the present invention, the freezing point is adjusted to 0 ° C. to −0 ° C. by changing the types of the mineral acids and alkali metal hydroxides, and the amount of metal silicon, mineral acids, and alkali metal hydroxides charged. It can be adjusted to any value within the range of 80 ° C.

  The longitudinal wave sound velocity from 20 ° C. to the solidification start point by the ultrasonic method with a frequency of 5 Hz of the composition of the present invention is not particularly limited, but is preferably in the range of 1500 to 2300 m / s.

  When the longitudinal wave sound velocity was measured by the ultrasonic longitudinal method of 5 Hz while continuously lowering the temperature of the composition of the present invention from 20 ° C. to −100 ° C., the longitudinal wave sound velocity was almost between 20 ° C. and the solidification start point. It is constant, the saturated water permeation peak disappears near the freezing point, a gel ice peak appears instead, and the strength of the gel ice peak increases with decreasing temperature. The composition of the present invention has the property of advancing and attenuating between longitudinal wave velocities of 1500-2400 m / s.

The composition of the present invention can be returned to the state of constant longitudinal wave sound speed similar to that before the temperature decrease even when the temperature is decreased from + 20 ° C. to −100 ° C. and then returned to 20 ° C. again.
This indicates that the composition of the present invention can be used by circulating between + 20 ° C and -100 ° C, preferably between + 20 ° C and -70 ° C, more preferably between + 20 ° C and -50 ° C. ing.

  It is preferable that the composition of the present invention does not powder when heated to 120 ° C. If the colloid is dispersed, it is dried at 100 ° C. to form a powder, but the composition of the present invention has a property of forming a paste even when dried at 120 ° C.

  As described above, the composition of the present invention can be used by circulating between + 20 ° C. and −100 ° C. and is not powdered even when heated to 120 ° C. It can be said that the inventive composition can be circulated and used in a temperature range between −80 ° C. and + 100 ° C.

While the density of the composition of the present invention is not particularly limited, usually, 1~2.0g / cm ^3, preferably 1.2~1.8g / cm ^3. The density of the composition of the present invention can be measured by a floating specific gravity bottle method.

  Although the viscosity of this invention composition is not specifically limited, Usually, 1-100 mPs * s, Preferably it is 1-30 mPa / s. The viscosity of the aqueous solution can be measured with, for example, an MKS (Maron Xrleger Sinko) viscometer.

  The specific heat of the composition of the present invention is usually 5 to 20 times that of water, and has an excellent cold storage / storage effect. The molar specific heat of the composition of the present invention is usually 4 to 50 J / K · mole.

  The freezing point can be further lowered by adding alcohols such as methanol and ethanol to the composition of the present invention. The amount of alcohol to be added is not particularly limited as long as it is within a range where the nonflammability effect can be maintained, but is usually 10% by weight or less based on the composition of the present invention.

2) Snow melting and anti-icing agent The snow melting and anti-icing agent of the present invention is characterized by containing the silicon-containing inorganic composition of the present invention. The composition of the present invention has a freezing point of 0 ° C. to −80 ° C., has excellent heat storage and cold storage effects, and emits heat of fusion at a low temperature, as will be described later, and thus is useful as a snow melting / freezing prevention agent.

  An excellent snow melting / freezing prevention effect can be obtained by spraying the snow melting / freezing prevention agent containing the composition of the present invention on roads, railways, runways and the like.

3) Snow melting / freezing prevention member The snow melting / freezing prevention member of the present invention is obtained by coating, impregnating or baking the silicon-containing inorganic composition of the present invention on the surface of various members.
As described above, the composition of the present invention has a freezing point of 0 ° C. to −80 ° C. and has excellent heat storage and cold storage effects. Therefore, a member having an excellent snow melting / freezing prevention function can be obtained by coating or impregnating the composition of the present invention on the surface of various members and drying to form a coating film or by baking. .

The amount of the composition of the present invention used when producing the snow melting / freezing prevention member of the present invention is not particularly limited, and an appropriate amount can be set according to the use and the like. The amount of the composition of the present invention is ^{usually, 100g / m 2 ~3000g / m} 2, preferably from ^{250g / m 2 ~2000g / m 2} .
The member is not particularly limited, and examples thereof include building members such as roofing materials, wall materials, doors, and pillar materials; various blocks, steps of stairs, and the like.

4) Circulating liquid The circulating liquid of the present invention contains the silicon-containing inorganic composition of the present invention and is characterized in that it can be circulated at -50 ° C to + 100 ° C.
As described above, the composition of the present invention can theoretically be used in a temperature range between −100 ° C. and + 120 ° C., but it can be used stably over a long period of time. In consideration, it is practical to circulate in a temperature range between −50 ° C. and + 100 ° C.

  The circulating fluid of the present invention can be used in a wide temperature range of −50 ° C. to + 100 ° C. As the circulating liquid of the present invention, the composition of the present invention which is an aqueous solution of an inorganic polymer compound is used. The inorganic polymer compound has the same quality as the inorganic fertilizer component, and there is no risk of soil contamination or air pollution even when it collapses and leaks due to an earthquake.

  The circulating fluid of the present invention is used for food refrigeration, food / beverage coolant, ice making equipment, cold storage air conditioning equipment, refrigeration / refrigerator, industrial refrigeration system, logistics system cold insulation, medical or head cooler refrigerant, etc. It can be used in various industrial fields.

  EXAMPLES Hereinafter, although an Example demonstrates this invention further in detail, this invention is not limited at all by the following Example.

(Example 1) Production of silicon-containing inorganic composition In water, metal silicon, mineral minerals shown in Table 1, and alkali metal hydroxide shown in Table 1 are mixed in proportions (parts by weight) shown in Table 1. ) To obtain silicon-containing inorganic compositions (compositions (A-1) to (A-7)). The reaction temperature is 40-60 ° C in all cases.

(Measurement of IR spectrum)
The FT-IR spectra of the compositions (A-1) to (A-3) obtained above were measured. The measured FT-IR spectrum is shown in FIG.
In FIG. 1, the horizontal axis represents wave number (cm-1), the vertical axis represents absorbance, a is the composition (A-1), b is the composition (A-2), and c is the composition (A-3). FIG.

In either case, it was suggested that the silicon compound contained in the aqueous solution was a mixture of silanol salt and siloxane. Moreover, there is almost no free water peak observed in the vicinity of 1600 cm ⁻¹ , and the silicon compounds contained in the compositions (A-1) to (A-3) have a small amount of free water. I understand that.

(Measurement of freezing point)
The DSC of the compositions (A-1) to (A-7) obtained above was measured. The measurement results are shown in FIGS. 2-8, a horizontal axis | shaft represents measurement temperature (degreeC) and a vertical axis | shaft represents calorie | heat amount (mcal / s). The freezing points of the compositions (A-1) to (A-7) obtained from the DSC measurement results are summarized in Table 2. It can be seen that the solidification start point can be set to an arbitrary value by changing the components to be used (particularly, the types and amounts of use of the mineral acids).

  As an example, in the case of the composition (A-6), the endothermic amount when freezing and the exothermic amount when melting are shown in FIG. As shown in FIG. 7, the endothermic amount when freezing (9.70 cal / g) and the exothermic amount when melting (9.85 cal / g) were almost the same.

  The specific heat of the composition (A-6) was 11.34 cal / g, which was about 10 times or more larger than the specific heat of water was 1 cal / g.

  Moreover, the solidification start point could be further lowered to 5 to 15 ° C. by adding 5% by weight of ethanol to the compositions (A-1) to (A-7).

(Measurement of longitudinal wave velocity)
The longitudinal wave sound velocity was measured when the temperature was continuously lowered to + 20 ° C. to −100 ° C. of the compositions (A-1) to (A-3). The measurement results are shown in FIGS. In the figure, the horizontal axis represents the measured temperature (° C.), and the vertical axis represents the longitudinal wave velocity (m / s). The measurement was performed using a supersonic measuring device manufactured by Toshiba Tungaloy at a longitudinal wave frequency of 5 MHz, a temperature drop rate of 2 ° C./minute, a measurement temperature region of −100 ° C. to + 20 ° C., and a measurement pressure of atmospheric pressure.

  As a result of the measurement, the longitudinal sound velocity from 20 ° C. to the solidification start point of the compositions (A-1) to (A-3) is between 1500 and 2400 m / s, and the viscosity change based on the temperature change is observed. Also shown. This measurement result almost coincided with the DSC thermal analysis result.

  In addition, as shown in FIG. 12, when the temperature of the composition (A-1) is lowered to −100 ° C. and then raised again to 20 ° C. (see the arrow in the figure), the change in longitudinal wave sound velocity is changed. Although the temperature was different from that at the time of temperature drop, when the temperature was around 250 (K) or more, the longitudinal sound velocity was the same as before the temperature drop. This has shown that the composition (A-1) can be recycled between + 20 ° C. and −100 ° C.

(Powdering experiment)
5 g of each of the compositions (A-1) to (A-7) was taken in a glass container and dried in an electric furnace at 120 ° C. for 3 hours. It was shown that the film-formed product remained even after free water was removed.

(Example 2) Production of composition of interlocking with snow melting or freezing prevention function qs (A-1) to the interlocking (ILB) surface ^{(250g / m 2 ~2000g / m} 2) was coated, baked at 500 ° C. As a result, an interlocking with a function to prevent snow melting and freezing was manufactured. As shown in FIG. 13, when this was left in the snowfall (e) at −5 ° C., the snow on the interlocking (d) melted, and the melted water was not frozen. The effect of preventing melting and freezing by melting heat was shown.

Example 3
An appropriate amount (about 2000 g) of the composition (A-3, specific gravity 1.3) and a solution (composition A-3a) having a specific gravity of 1.45 by concentrating the composition (A-3) on the ILB surface. / M < ² >), and heat drying to form a coating film to obtain ILB with snow melting / freezing prevention function. Next, as shown in FIG. 14, it was placed overnight in the snowfall of −5 ° C. in parallel with the untreated ILB.

  In FIG. 13, h is an untreated ILB (ILB (h)), f is a composition (A-3a) applied (ILB (f)), and g is a composition (A-3) applied. (ILB (g)).

  As shown in FIG. 14, the snow on ILB (f) was not completely melted, but was not frozen. In the daytime, it melted with sunlight and melted snow. The snow on ILB (g) was not completely melted, but was not frozen. In the daytime, it melted with sunlight and melted snow. The time to complete snow melting was longer than ILB (f). On the other hand, snow was piled up on ILB (h) and was frozen. Since the outside air temperature was −3 ° C., snow did not melt even in the daytime. Freezing was gone.

It is a FT-IR spectrum figure of composition (A-1)-(A-3). It is a DSC chart figure of a composition (A-1). It is a DSC chart figure of a composition (A-2). It is a DSC chart figure of a composition (A-3). It is a DSC chart figure of a composition (A-4). It is a DSC chart figure of a composition (A-5). It is a DSC chart figure of a composition (A-6). It is a DSC chart figure of a composition (A-7). It is a graph which shows the change of the longitudinal-wave sound speed from +20 degreeC--100 degreeC about a composition (A-1). It is a graph which shows the change of the longitudinal wave sound speed from +20 degreeC--100 degreeC about a composition (A-2). It is a graph which shows the change of the longitudinal wave sound speed from +20 degreeC--100 degreeC about a composition (A-3). It is a graph which shows the change of the longitudinal-wave sound speed when it is made to raise to +20 degreeC again after making it fall to +20 degreeC--100 degreeC about a composition (A-1). In the schematic diagram after applying an appropriate amount of the composition (A-1) to the surface of the interlocking block and baking it at 500 ° C. and leaving the interlocking with snow melting / freezing prevention function in the snowfall (e) at −5 ° C. overnight. is there. Applying an appropriate amount of the composition (A-3, specific gravity 1.3) and the composition (A-3a, specific gravity 1.45) to the surface of the interlocking block (ILB) and drying it to prevent snow melting and freezing It is a schematic diagram after installing overnight with -5 degreeC snowfall in parallel with ILB with a function, and unprocessed ILB.

Claims (6)

  (1) Metallic silicon, (2) Fluoride, phosphorous acid, phosphite, nitrous acid, nitrite, carbonic acid, carbonate, carboxylic acid having 1 to 10 carbon atoms, carboxylate having 1 to 10 carbon atoms And at least one selected from the group consisting of inosit, and (3) a silicon-containing inorganic composition obtained by reacting an alkali metal hydroxide in water, wherein the freezing point is 0 ° C. to −80 ° C. A silicon-containing inorganic composition characterized.   2. The silicon-containing inorganic composition according to claim 1, wherein the longitudinal wave sound velocity from 20 ° C. to the solidification start point by an ultrasonic method having a frequency of 5 Hz is in the range of 1500 to 2300 m / s.   The silicon-containing inorganic composition according to claim 1 or 2, wherein the silicon-containing inorganic composition is not powdered even when heated to 120 ° C.   A snow melting / freezing preventing agent comprising the silicon-containing inorganic composition according to claim 1.   A snow melting / freezing prevention member obtained by applying, impregnating or baking the silicon-containing inorganic composition according to any one of claims 1 to 3 to a member surface. A circulating liquid comprising the silicon-containing inorganic composition according to claim 1 and capable of being circulated at -50 ° C to + 100 ° C.

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