JP2004269561A - Cool storage or heat storage material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To develop a cool storage or heat storage material which enables maintenance of articles in a predetermined temperature range required. <P>SOLUTION: This cool storage or heat storage material is obtained by mixing a plurality of polyethylene glycols having different temperatures in freezing points from each other and an average molecular weight of 200-20,000 as the major component at a mixing ratio so as for at least two polyethylene glycols having different temperatures in freezing points from each other to have the freezing point of a predetermined temperature and housing the resulting mixture in a water-impermeable bag to seal it, and by rendering the mixture thus housed and sealed in a solidified state and placing it together with a necessary article in an insulating container for use, the article can be maintained for a long time in the predetermined temperature range required by the article due to the latent heat of the mixture. <P>COPYRIGHT: (C)2004,JPO&NCIPI

Description

表１中のポリエチレングリコールは、いずれも三洋化成工業株式会社製のものである。
【００１６】
まず、表１に記載のポリエチレングリコールの内、例えば、平均分子量が２００のＰＥＧ−２００と平均分子量が６００のＰＥＧ−６００とをそれぞれ５０重量部づつ配合して混合すると、その混合物の凝固点の温度は約−１５℃になる。この場合の計算は次のとおりである。
【計算】
−５０℃×５０重量部＋２０℃×５０重量部＝−１５００
−１５００÷５０＝−３０
−３０×０．５（ＰＥＧ−２００の占める割合）＝−１５
∴凝固点の温度は約−１５℃となる。
【００１７】
また、例えば、ＰＥＧ−２００を５０重量部とＰＥＧ−６００を３０重量部配合して混合すると、その混合物の凝固点の温度は約−２３℃となる。この場合の計算は次のとおりである。
【計算】
−５０℃×５０重量部＋２０℃×３０重量部＝−１９００
−１９００÷５０＝−３８
−３８×０．６２（ＰＥＧ−２００の占める割合）＝−２３．５６
∴凝固点の温度は約−２３℃となる。
【００１８】
更に、例えば、ＰＥＧ−２００を３０重量部とＰＥＧ−６００を５０重量部配合して混合すると、その混合物の凝固点の温度は約−６℃となる。この場合の計算は次のとおりである。
【計算】
−５０℃×３０重量部＋２０℃×５０重量部＝−５００
−５００÷３０＝−１６．７
−１６．７×０．３８（ＰＥＧ−２００の占める割合）＝−６．３４
∴凝固点の温度は約−６℃となる。
【００１９】
また、例えば、ＰＥＧ−３００を４０重量部とＰＥＧ−４００を５０重量部配合して混合すると、その混合物の凝固点の温度は約−２℃となる。この場合の計算は次のとおりである。
【計算】
−１３℃×４０重量部＋７℃×５０重量部＝−１７０
−１７０÷４０＝−４．２
−４．２×０．４４（ＰＥＧ−３００の占める割合）＝−１．８
∴凝固点の温度は約−２℃となる。
【００２０】
更にまた、例えば、ＰＥＧ−３００を５０重量部とＰＥＧ−１５００を２０重量部配合して混合すると、その混合物の凝固点の温度は約２℃となる。この場合の計算は次のとおりである。
【計算】
−１３℃×５０重量部＋４０℃×２０重量部＝＋１５０
＋１５０÷５０＝＋３
＋３×０．７（ＰＥＧ−３００の占める割合）＝＋２．１
∴凝固点の温度は約２℃となる。
【００２１】
また、例えば、ＰＥＧ−３００を３０重量部とＰＥＧ−６００を５０重量部配合して混合すると、その混合物の凝固点の温度は約８℃となる。この場合の計算は次のとおりである。
【計算】
−１３℃×３０重量部＋２０℃×５０重量部＝＋６１０
＋６１０÷３０＝＋２０．３
＋２０．３×０．３８（ＰＥＧ−３００の占める割合）＝＋７．７
∴凝固点の温度は約８℃となる。
【００２２】
前記計算は、いずれも配合量から計算したものであるが、混合物の凝固点の温度側から計算する場合には、下記計算式に基づいて異なる凝固点温度のポリエチレングリコールの配合率を計算して、予定した混合物を得ることができる。
【計算式】
設定温度＝Ａ凝固点×Ｘ＋Ｂ凝固点×Ｙ
であり、Ｙ＝１−Ｘとして計算する。
【００２３】
例えば、異なる凝固点温度のポリエチレングリコールとして、ＰＥＧ−４００とＰＥＧ−３００を選択した場合に、
【計算】
０℃＝７（ＰＥＧ−４００の凝固点）Ｘ＋（−１３（ＰＥＧ−３００の凝固点）Ｙ）
となり、Ｙ＝１−Ｘを代入すると、
０℃＝７Ｘ＋（−１３）（１−Ｘ）
０＝７Ｘ−１３＋１３Ｘ、 ２０Ｘ＝１３
Ｘ＝１３／２０＝０．６５
∴ＰＥＧ−４００が６５％、残りのＰＥＧ−３００が３５％
となるのである。
【００２４】
また、前記と同じ材料を使用して、例えば、５℃の混合物を得る場合の計算の一例を示すと、
５℃＝７Ｘ＋（−１３）（１−Ｘ）
５＝７Ｘ−１３＋１３Ｘ、 ５＋１３＝２０Ｘ
Ｘ＝１８／２０＝０．９
∴ＰＥＧ−４００が９０％、残りのＰＥＧ−３００が１０％
となる。
【００２５】
このように、表１に記載のポリエチレングリコールの種類を適宜選択して、２種類以上を適宜の割合で混合することにより、凝固点の温度がそれぞれ異なる混合物を得ることができ、その混合物を使用して予定した温度範囲に維持できるようにすることができるのである。
【００２６】
この場合に、図１及び図２に示したように、例えば、非透水性の袋体１に凝固点温度の異なるポリエチレングリコールの混合物２を所要量収納すると共に、一種の増量材として所要量（３０〜７０％の範囲）の水を加えて全体を均一に混合攪拌して収納し、密封状態にする。
【００２７】
使用される非透水性の袋体１は、例えば、ナイロンとポリエチレンのラミネートシートを使用し、好ましくは、表面側となる面に不織布３を一体的に取り付けた構成を有するものである。表面側に不織布３が貼着されていると、例えば、温度をマイナス側に設定して凍結させて使用した場合に、表面に結露が生じないのであり、それによって、低温に維持しようとする物品に対し水滴による悪影響を及ぼさないのである。
【００２８】
実際の使用に際して、ポリエチレングリコールの混合物２における凝固点の温度が、例えば、−１５℃であって、その混合物と略等量の水を加えて袋体１に密封して蓄冷材とした場合に、その蓄冷材は−２０℃以下の温度で凝固させ（凍結状態）、例えば、−１０℃程度の低温で維持しなければならない物品と一緒に、所定の断熱容器（保温容器）に入れて密閉する。
【００２９】
この状態において、蓄冷材は凝固点が−１５℃であるため、その潜熱によって断熱容器の内部温度が−１５℃に近い−１３℃程度以下に維持され、物品もその温度下に維持されるのである。従って、蓄冷材が凝固状態にある間は、断熱容器の内部温度は、予定した温度に長時間に渡っていじできるのである。
【００３０】
また、物品によっては、それほど低温ではないが、０℃以下に維持したいような場合には、例えば、−２〜−３℃程度の凝固点温度を有する混合物を、前記同様に袋体１に収納し、その混合物に対して７０重量部の水を一緒に封入して蓄冷材を形成する。
【００３１】
このように形成した蓄冷材は、約−１０℃程度の温度で凝固させ（凍結状態）て使用するものであり、０℃以下に維持したい物品と一緒に所要の断熱容器に収納し密封する。この状態で、蓄冷材の潜熱によって断熱容器の内部温度が０℃以下に維持されるのであり、しかも、凝固状態にある間はその０℃以下の温度が維持される。
【００３２】
いずれにしても、凝固点の温度が異なる複数のポリエチレングリコールを適宜の配合比を選択して使用することによって、凝固点の温度を任意に設定した混合物を得ることができ、その混合物を適宜の袋体に収納して密封して蓄冷または蓄熱材とするものであり、該蓄冷または蓄熱材を凝固状態（凍結）にして使用することによって、凝固状態から溶解するときの潜熱で周囲温度を、凝固点の温度に近い温度に維持することができるのである。
【００３３】
なお、混合物と一緒に所要量の水を袋体に収納密封するものであるが、水の凍結及び溶解温度は０℃であることから、混合物と一緒に混ざった状態では、混合物の特性が生かされて凝固点の温度には大きな影響を及ぼさないのである。
【００３４】
また、前記実施の形態では、比較的低温のものについて説明したが、例えば、１０℃〜１５℃の間に温度管理しなければならないような物品に対しては、それに合わせて混合物を造れば良いのであり、混合物の凝固点温度は、いかようにも設定できる点に本発明の特徴が存するのである。
【００３５】
【発明の効果】
以上説明したように、本発明に係る蓄冷または蓄熱材は、平均分子量が２００〜２００００の範囲で、凝固点の温度がそれぞれ異なる複数のポリエチレングリコールを主剤とし、凝固点の温度が異なる少なくとも２種類のポリエチレングリコールを予定した温度の凝固点になるように配合比率を設定して混合し、該混合物を非透水性の袋体に収納密封したものであって、収納密封された混合物を凝固状態にして所要の物品と一緒に断熱容器に入れて使用することにより、該混合物の潜熱によって物品が要求されている予定した温度範囲に長時間に渡って維持できるという優れた効果を奏する。
【００３６】
また、非透水性の袋体は、その表面に不織布が一体に取り付けられている構成であるため、マイナスからプラスの範囲の低温の状態であっても、その表面に結露が生じないのであり、結露による物品への悪影響を及ぼさないという優れた効果を奏する。
【図面の簡単な説明】
【図１】本発明に係る蓄冷または蓄熱材の一例を示す斜視図である。
【図２】図１のＡ−Ａ線に沿う一部拡大断面図である。
【符号の説明】
１ 非透水性の袋体
２ 混合物
３ 不織布[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention is used when foods, processed foods, pharmaceuticals, or other articles or goods are transported in a state where temperature control is required, or when it is necessary to temporarily store them in a place without cooling equipment It relates to a cold storage or heat storage material to be used.
[0002]
[Prior art]
Conventionally, various types of cold storage or heat storage materials have been known. For example, it is a cold insulator emphasizing flexibility even at low temperatures, and the water-absorbing gel particles of a water-insoluble polymer whose surface is coated with a water-insoluble, non-water-absorbing polymer film contains a water-soluble polymer, water and hydrophilic alcohols. A gel-like cold insulator having low-temperature flexibility suspended in an aqueous gel is known.
[0003]
As the above-mentioned water-soluble polymer, polymerization using at least one of acrylamide, acrylic acid, 2-methyl-2-acrylamidopropanesulfonic acid, acryloyloxyethyltrimethylammonium quaternary salt, and acryloyloxyethyldialkylamine salt as a structural unit. Are listed as preferred examples.
[0004]
This known gel-like cold insulator is usually used as a cold insulator by freezing under conditions of -30 to -5 ° C, preferably at -20 to -15 ° C for 1 to 24 hours. It is described that it has flexibility even during freezing and does not change its flexibility even when used repeatedly (see Patent Document 1).
[0005]
Further, as a heat storage agent having high safety to the human body and the environment, a mixture of 0.05 to 2.5% by weight of sodium benzoate and 97.5 to 99.95% by weight of water is known, In particular, an excellent heat storage effect is exhibited in a temperature range of -2 ° C to + 2 ° C in a range of 0.05 to 1.0% by weight as a blending amount of sodium benzoate (Patent Document 2).
[0006]
[Patent Document 1]
Japanese Patent Publication No. 7-81134 (pages 1 to 5)
[Patent Document 2]
JP-A-2002-97460 (pages 2 to 4)
[0007]
[Problems to be solved by the invention]
However, the gel-like cold insulator of the above-mentioned Patent Document 1 has flexibility both at the time of freezing and at the time of use, and is merely a cold insulator for maintaining a low temperature below freezing.
[0008]
The heat storage agent disclosed in the above-mentioned Patent Document 1 uses sodium benzoate, but its blending amount is extremely small, and 97% or more is mainly composed of water. ) Predominates the heat storage effect and keeps it close to the melting temperature of ice.
[0009]
By the way, in foodstuffs or commodities, it is required not only to maintain the temperature below the freezing point or the freezing point, but also to maintain the temperature in a range of, for example, 3 to 7 ° C. or a substantially constant temperature in the vicinity of 10 ° C. depending on the type. There are things to be done. However, in any of the above-mentioned known examples, there is no mention of maintaining the temperature within a predetermined range, and there is no mention of such necessity.
[0010]
Therefore, in the prior art, there is a problem in developing a cold storage or heat storage material that can be maintained in a required predetermined temperature range.
[0011]
[Means for Solving the Problems]
As a specific means for solving the above-mentioned problems, the present invention comprises a plurality of polyethylene glycols each having a different freezing point temperature, having an average molecular weight in the range of 200 to 20,000, and at least two kinds of polyethylene glycols having different freezing point temperatures. The present invention provides a cold storage or heat storage material characterized in that the mixing ratio is set so as to be a freezing point at a predetermined temperature, the mixture is mixed, and the mixture is stored and sealed in a water-impermeable bag.
[0012]
In the present invention, an additional requirement is that a required amount of water is added to the mixture; and that the non-permeable bag has a nonwoven fabric integrally attached to its surface.
[0013]
The regenerative or heat storage material according to the present invention is a mixture of at least two kinds of polyethylene glycols having different freezing points in a blending ratio set so as to have a predetermined freezing point, and polyethylene glycols having different freezing points. Are compatible with each other without separation even when the two types are mixed, and the properties of both, ie, the temperature of the freezing point, are exhibited in the middle. Therefore, by appropriately selecting the mixing ratio, the substance having the predetermined freezing point temperature can be obtained. Is easily obtained.
[0014]
BEST MODE FOR CARRYING OUT THE INVENTION
Next, an embodiment of a cold storage or heat storage material according to the present invention will be described with reference to the drawings. Although polyethylene glycol is used as the cold storage or heat storage material, a heat storage material that can maintain the surroundings at a predetermined temperature can be obtained by mixing at least two types of polyethylene glycol having different characteristics.
[0015]
Table 1 shows polyethylene glycols having different properties used in the present invention.
[Table 1]

The polyethylene glycols in Table 1 are all manufactured by Sanyo Chemical Industries, Ltd.
[0016]
First, among the polyethylene glycols listed in Table 1, for example, PEG-200 having an average molecular weight of 200 and PEG-600 having an average molecular weight of 600 were blended by 50 parts by weight, and the temperature of the freezing point of the mixture was obtained. Will be about -15 ° C. The calculation in this case is as follows.
[Calculation]
-50 ° C x 50 parts by weight + 20 ° C x 50 parts by weight = -1500
-1500 ÷ 50 = -30
−30 × 0.5 (ratio occupied by PEG-200) = − 15
∴ The freezing point temperature is about -15 ° C.
[0017]
Further, for example, when 50 parts by weight of PEG-200 and 30 parts by weight of PEG-600 are blended and mixed, the temperature of the freezing point of the mixture is about −23 ° C. The calculation in this case is as follows.
[Calculation]
−50 ° C. × 50 parts by weight + 20 ° C. × 30 parts by weight = −1900
-1900 ÷ 50 = -38
−38 × 0.62 (ratio of PEG-200) = − 23.56
∴ The freezing point temperature is about -23 ° C.
[0018]
Further, for example, when 30 parts by weight of PEG-200 and 50 parts by weight of PEG-600 are blended and mixed, the temperature of the freezing point of the mixture becomes about −6 ° C. The calculation in this case is as follows.
[Calculation]
−50 ° C. × 30 parts by weight + 20 ° C. × 50 parts by weight = −500
−500 ÷ 30 = −16.7
−16.7 × 0.38 (ratio of PEG-200) = − 6.34
∴ The freezing point temperature is about -6 ° C.
[0019]
Further, for example, when 40 parts by weight of PEG-300 and 50 parts by weight of PEG-400 are blended and mixed, the temperature of the freezing point of the mixture is about −2 ° C. The calculation in this case is as follows.
[Calculation]
−13 ° C. × 40 parts by weight + 7 ° C. × 50 parts by weight = −170
-170 / 40 = -4.2
-4.2 * 0.44 (ratio of PEG-300) =-1.8
∴ The freezing point temperature is about -2 ° C.
[0020]
Furthermore, for example, when 50 parts by weight of PEG-300 and 20 parts by weight of PEG-1500 are blended and mixed, the temperature of the freezing point of the mixture is about 2 ° C. The calculation in this case is as follows.
[Calculation]
-13 ° C × 50 parts by weight + 40 ° C. × 20 parts by weight = + 150
+ 150 ÷ 50 = + 3
+ 3 × 0.7 (ratio of PEG-300) = + 2.1
∴ The freezing point temperature is about 2 ° C.
[0021]
For example, when 30 parts by weight of PEG-300 and 50 parts by weight of PEG-600 are blended and mixed, the temperature of the freezing point of the mixture is about 8 ° C. The calculation in this case is as follows.
[Calculation]
−13 ° C. × 30 parts by weight + 20 ° C. × 50 parts by weight = + 610
+ 610/30 = + 20.3
+ 20.3 × 0.38 (ratio occupied by PEG-300) = + 7.7
∴ The freezing point temperature is about 8 ° C.
[0022]
Although the above calculations are all calculated from the compounding amount, when calculating from the temperature side of the freezing point of the mixture, the mixing ratio of polyethylene glycol having different freezing point temperatures is calculated based on the following formula, and The resulting mixture can be obtained.
【a formula】
Set temperature = A freezing point x X + B freezing point x Y
, And is calculated as Y = 1−X.
[0023]
For example, when PEG-400 and PEG-300 are selected as polyethylene glycols having different freezing points,
[Calculation]
0 ° C. = 7 (freezing point of PEG-400) X + (− 13 (freezing point of PEG-300) Y)
And substituting Y = 1−X,
0 ° C. = 7X + (− 13) (1-X)
0 = 7X-13 + 13X, 20X = 13
X = 13/20 = 0.65
∴65% PEG-400, 35% PEG-300
It becomes.
[0024]
Also, using the same material as above, for example, to show a calculation example when obtaining a mixture at 5 ° C.,
5 ° C = 7X + (-13) (1-X)
5 = 7X-13 + 13X, 5 + 13 = 20X
X = 18/20 = 0.9
∴ PEG-400 90%, remaining PEG-300 10%
It becomes.
[0025]
As described above, by appropriately selecting the types of polyethylene glycol described in Table 1 and mixing two or more types in an appropriate ratio, it is possible to obtain mixtures having different solidification points, and use the mixture. Temperature can be maintained in a predetermined temperature range.
[0026]
In this case, as shown in FIGS. 1 and 2, for example, a required amount of a mixture 2 of polyethylene glycols having different freezing points is stored in a water-impermeable bag 1 and a required amount (30 (In the range of 70% to 70%), and the whole is uniformly mixed with stirring, stored, and sealed.
[0027]
The impermeable bag 1 used is, for example, a laminated sheet of nylon and polyethylene, and preferably has a configuration in which the nonwoven fabric 3 is integrally attached to the surface that is to be the front side. When the nonwoven fabric 3 is adhered to the surface side, for example, when the temperature is set to the minus side and the product is used after being frozen, dew condensation does not occur on the surface, whereby the article to be maintained at a low temperature is used. It does not have any adverse effects on water.
[0028]
In actual use, when the temperature of the freezing point in the polyethylene glycol mixture 2 is, for example, −15 ° C., and the mixture is added with substantially the same amount of water and sealed in the bag body 1 to obtain a cold storage material, The regenerator material is solidified at a temperature of −20 ° C. or lower (frozen state) and, for example, is put in a predetermined heat-insulating container (insulated container) together with an article which must be maintained at a low temperature of about −10 ° C. and sealed. .
[0029]
In this state, since the freezing material has a freezing point of -15 ° C, the latent heat keeps the internal temperature of the heat insulating container at about -13 ° C or lower, which is close to -15 ° C, and the article is also maintained at that temperature. . Therefore, while the regenerator material is in a solidified state, the internal temperature of the heat insulating container can be maintained at a predetermined temperature for a long time.
[0030]
In addition, if the temperature is not so low depending on the article but it is desired to maintain the temperature at 0 ° C. or lower, for example, a mixture having a freezing point temperature of about −2 to −3 ° C. is stored in the bag body 1 as described above. And 70 parts by weight of water are sealed together with the mixture to form a regenerator.
[0031]
The regenerative material thus formed is used after being solidified (frozen state) at a temperature of about −10 ° C., and is stored and sealed in a required heat-insulating container together with an article to be maintained at 0 ° C. or lower. In this state, the internal temperature of the heat insulating container is maintained at 0 ° C. or lower by the latent heat of the cold storage material, and the temperature of 0 ° C. or lower is maintained during the solidification state.
[0032]
In any case, by using a plurality of polyethylene glycols having different freezing points at appropriate mixing ratios, a mixture in which the freezing point temperature is arbitrarily set can be obtained, and the mixture can be obtained in an appropriate bag. The heat storage material is sealed and stored as a cold storage or heat storage material. By using the cold storage or heat storage material in a solidified state (frozen), the ambient temperature is determined by the latent heat at the time of melting from the solidified state. It can be maintained at a temperature close to the temperature.
[0033]
The required amount of water is stored and sealed in the bag together with the mixture. However, since the freezing and melting temperature of water is 0 ° C, the characteristics of the mixture can be exploited when mixed with the mixture. It has no significant effect on the temperature of the freezing point.
[0034]
Further, in the above-described embodiment, a relatively low temperature is described. For example, for an article whose temperature needs to be controlled between 10 ° C. and 15 ° C., a mixture may be prepared according to the temperature. The feature of the present invention resides in that the freezing point temperature of the mixture can be set in any manner.
[0035]
【The invention's effect】
As described above, the regenerative or thermal storage material according to the present invention has an average molecular weight in the range of 200 to 20,000, a plurality of polyethylene glycols each having a different freezing point temperature, and at least two types of polyethylene having different freezing points. The glycol is mixed and set at a blending ratio so as to have a freezing point at a predetermined temperature, and the mixture is stored and sealed in a water-impermeable bag. When used in an insulated container together with an article, the article has an excellent effect that the latent heat of the mixture allows the article to be maintained in a required predetermined temperature range for a long time.
[0036]
In addition, since the non-permeable bag has a structure in which the nonwoven fabric is integrally attached to the surface, even in a low temperature range from minus to plus, no condensation occurs on the surface, It has an excellent effect that it does not adversely affect articles due to condensation.
[Brief description of the drawings]
FIG. 1 is a perspective view showing an example of a cold storage or heat storage material according to the present invention.
FIG. 2 is a partially enlarged sectional view taken along the line AA of FIG.
[Explanation of symbols]
DESCRIPTION OF SYMBOLS 1 Impermeable bag 2 Mixture 3 Nonwoven fabric

Claims (3)

The average molecular weight is in the range of 200 to 20,000, and based on a plurality of polyethylene glycols each having a different freezing point temperature,
At least two kinds of polyethylene glycols having different freezing points are mixed by setting the mixing ratio so as to have a predetermined freezing point,
A cold storage or heat storage material, wherein the mixture is stored and sealed in a water-impermeable bag. To the mixture,
The cold storage or heat storage material according to claim 1, wherein a required amount of water is added. The impermeable bag,
The cold storage or heat storage material according to claim 1, wherein a nonwoven fabric is integrally attached to the surface.

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