U.S. patent application number 12/295598 was filed with the patent office on 2009-10-01 for peltier device and temperature regulating container equipped with the peltier device.
This patent application is currently assigned to KITAKYUSHU FOUNDATION FOR THE ADVANCEMENT OF INDUSTRY, SCIENCE AND TECHNOLOGY. Invention is credited to Kenichi Kobayashi, Kazumi Manabe, Akira Morishige, Tetsuaki Nishida.
Application Number | 20090241554 12/295598 |
Document ID | / |
Family ID | 38563584 |
Filed Date | 2009-10-01 |
United States Patent
Application |
20090241554 |
Kind Code |
A1 |
Nishida; Tetsuaki ; et
al. |
October 1, 2009 |
PELTIER DEVICE AND TEMPERATURE REGULATING CONTAINER EQUIPPED WITH
THE PELTIER DEVICE
Abstract
An object of the present invention is to provide a Peltier
device capable of retaining a certain temperature at a high
accuracy by using a conductive glass consisting primarily of
vanadate as an electrode, excellent in handleability, easy in
temperature regulation, excellent in stability of cooling
performance, capable of securely preventing an electrode from
corrosion resulting from chemicals or dew condensation etc., and
excellent in reliability and durability of the electrode. The
Peltier device has a heat absorbing portion and a heat emitting
portion, in which at least the electrode of the heat absorbing
portion is formed with the conductive glass consisting primarily of
vanadate.
Inventors: |
Nishida; Tetsuaki; (Fukuoka,
JP) ; Kobayashi; Kenichi; (Tokyo, JP) ;
Morishige; Akira; (Kanagawa, JP) ; Manabe;
Kazumi; (Tokyo, JP) |
Correspondence
Address: |
SUGHRUE MION, PLLC
2100 PENNSYLVANIA AVENUE, N.W., SUITE 800
WASHINGTON
DC
20037
US
|
Assignee: |
KITAKYUSHU FOUNDATION FOR THE
ADVANCEMENT OF INDUSTRY, SCIENCE AND TECHNOLOGY
Kitakyushu-shi
JP
|
Family ID: |
38563584 |
Appl. No.: |
12/295598 |
Filed: |
March 30, 2007 |
PCT Filed: |
March 30, 2007 |
PCT NO: |
PCT/JP2007/057034 |
371 Date: |
September 30, 2008 |
Current U.S.
Class: |
62/3.6 ;
220/592.01 |
Current CPC
Class: |
H01L 35/30 20130101 |
Class at
Publication: |
62/3.6 ;
220/592.01 |
International
Class: |
F25B 21/02 20060101
F25B021/02; B65D 88/74 20060101 B65D088/74 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 31, 2006 |
JP |
2006-100959 |
Claims
1. A Peltier device having a heat absorbing portion and a heat
emitting portion, wherein at least an electrode of the heat
absorbing portion is formed with a conductive glass consisting
primarily of vanadate.
2. A temperature regulating container having a container main body
and the Peltier device as set forth in claim 1 which is placed on
the bottom or the side of the container main body.
3. The temperature regulating container as set forth in claim 2,
wherein the container main body is at least partially formed with
the conductive glass.
4. The temperature regulating container as set forth in claim 3,
wherein the electrode of the heat absorbing portion of the Peltier
device is the conductive glass which forms at least a part of the
container main body.
5. The temperature regulating container as set forth in any one of
claim 2 to claim 4, which has heating means placed on the bottom or
the side of the container main body.
6. The temperature regulating container as set forth in claim 5,
wherein the heat element of the heating means is the conductive
glass which forms at least a part of the container main body.
7. The temperature regulating container as set forth in claim 6
which has an insulation portion for insulating the conductive glass
acting as the electrode of the heat absorbing portion of the
Peltier device and the conductive glass acting as the heat element
of the heating means.
8. The temperature regulating container as set forth in any one of
claim 3 to claim 7, wherein the conductive glass is film-formed on
the outer surface of the container main body.
Description
TECHNICAL FIELD
[0001] The present invention relates to a Peltier device easy in
regulating temperatures and excellent in handleability and also
relates to a temperature regulating container equipped with the
Peltier device capable of optimally regulating the temperature of a
specimen in making observations of tissues and cells in the body or
the operation thereof etc., in the research field etc., of
biotechnology or making microscopic observations and the operation
thereof, with the temperature of a specimen regulated, when quality
control or material tests etc., are conducted in medical and
industrial fields.
BACKGROUND OF THE INVENTION
[0002] Conventionally, in a temperature regulating system for
cultivation used in biotechnology and medical fields, a method is
used in which a medium such as an antifreeze liquid or water is
changed in temperature to circulate it around a specimen by using a
pump and a method in which the polarity of a cooling module is
shifted to attain a change in temperature or temperature
regulation. In the method in which a medium is changed in
temperature to circulate it by using a pump, there are problems
that a circulating channel of the medium must be retained heat to
result in larger dimensions of the system, thereby a difference in
temperature easily takes place during circulation, and the system
is insufficient in response to heating or cooling, thereby making
it difficult to regulate temperatures at a high accuracy.
[0003] In the method in which the polarity of a cooling module is
shifted to attain a change in temperature or temperature
regulation, there are problems that the cooling module is greatly
damaged and lacks a longer operation life and reliability as the
system.
[0004] Both of the above methods are able to heat and cool a
plurality of incubators or the like at the same time but have
problems that they are unable to individually heat and cool
containers having a very small accommodation space or selectively
heat and cool an incubator provided with a plurality of cells on a
single cell basis and therefore lack versatility.
[0005] Further, (Patent Document 1) has disclosed a method for
selecting cultured cells by using a temperature responsive
high-molecular compound in which cells cultured in an incubator
where the temperature responsive high-molecular compound is used as
a cell culture base material are observed microscopically at
temperatures higher than a critical point at which the temperature
responsive high-molecular compound starts to deposit from water, a
cooling fluid is sprayed to effect cooling, without blocking light
paths of transmitted light, until the temperature responsive
high-molecular compound within range of vision is cooled down to a
temperature lower than the critical point, thereby only desired
cells or cell masses are selected and removed from the container
for collection.
[0006] (Patent Document 2) has disclosed "a heating/cooling
dual-purpose system which is constituted in combination of a
temperature-elevating glass plate functioning as a heater in which
a positive electrode and a negative electrode are attached so as to
face each other around transparent glass on which a transparent
conducting film is formed by vacuum deposition and one or a
plurality of cooling modules utilizing the Peltier effect."
[0007] [Patent Document 1] Japanese Published Unexamined Patent
Application No. 2003-102466
[0008] [Patent Document 2] Japanese Published Unexamined Patent
Application No. H9-122507
DISCLOSURE OF THE INVENTION
Objects to be Solved by the Invention
[0009] However, the above-described conventional technologies have
the following problems.
(1) In the method for selecting cultured cells as disclosed in
(Patent Document 1), a heating plane for placing an incubator to
heat the bottom thereof, a hole opened at the center of the heating
plane for transmitting light in a small area and an ejection port
for spraying a cooling fluid to the bottom of the incubator facing
the hole are provided thereby making it possible to cool only a
small area. With an aim of selecting and collecting only desired
cells from several types of cells, this method has a problem that
it is unable to heat or cool a very small space at any given
temperature, used only in selecting cultured cells and therefore
lacking in versatility. (2) There is a problem that since the main
body is formed with hard glass, the heating/cooling dual-purpose
system as disclosed in (Patent Document 2) is difficult to subject
to fine processing, lacking in configuration flexibility, unable to
form a very small space for accommodating a chemical solution or an
aqueous solution etc., thereby lacking in handleability and
versatility.
[0010] The present invention has been made for solving the above
problems, an object of which is to provide a Peltier device capable
of retaining a certain temperature at a high accuracy by using a
conductive glass consisting primarily of vanadate as an electrode,
easy in temperature regulation and excellent in handleability and
also a temperature regulating container equipped with the Peltier
device which is easy in processing the container main body,
excellent in configuration flexibility, capable of forming a very
small space to accommodate a chemical solution or an aqueous
solution etc., excellent in chemical resistance and preservability,
capable of effectively heating or cooling a very small space at
which the chemical solution or the aqueous solution etc., is
accommodated and retaining it at any given temperature stably,
thereby making observations and various measurements effectively in
a short time and excellent in reliability, versatility and
workability.
Means for Solving the Objects
[0011] In order to solve the above problems, the Peltier device of
the present invention and the temperature regulating container
equipped with the Peltier device are constituted as follows.
[0012] The Peltier device of the first aspect of the present
invention is a Peltier device having a heat absorbing portion and a
heat emitting portion, in which at least an electrode of the heat
absorbing portion is constituted so as to be formed with a
conductive glass consisting primarily of vanadate.
[0013] According to the above constitution, the following actions
are obtained.
(1) Since the electrode of the heat absorbing portion is formed
with a conductive glass consisting primarily of vanadate, it is
possible to cool a target substance by changing temperatures
slowly. Therefore, the target substance is easy in temperature
regulation, able to retain temperatures at a high accuracy
approximately to a constant level and excellent in stability of
cooling temperatures. (2) Since the electrode is formed with a
conductive glass consisting primarily of vanadate, it is possible
to securely prevent the electrode from corrosion resulting from
chemicals or dew condensation etc., thereby making the electrode
excellent in reliability and durability.
[0014] In this instance, the conductive glass (vanadate glass)
consisting primarily of vanadate includes a vitrified substance by
adding alkali metal oxides such as diphosphate pentaoxide,
potassium oxide and sodium oxide, alkaline earth oxides such as
barium oxide, or cerium oxide, tin oxide, lead oxide and copper
oxide etc., to vanadium oxide.
[0015] This conductive glass is produced by a vitrification step in
which a vanadium-containing composition is vitrified to produce an
oxide glass and by a reheating step in which the oxide glass is
retained for a predetermined time at an annealing processing
temperature, or a temperature range higher than a glass transition
temperature of the oxide glass but lower than a melting point, and
preferably at a temperature higher than the crystallization
temperature of the oxide glass but lower than the melting
point.
[0016] A crystallization temperature and a melting point may be
determined through actual measurement of the oxide glass by using
differential thermal analysis (DTA) or differential scanning
calorimeter (DSC) etc. Further, it may also be determined by
thermodynamic calculation or the like using a constitutional
diagram of constituents to be estimated.
[0017] Where a crystallization temperature is determined by the
differential thermal analysis (DTA), a center point of heat
generation peak of crystallization or a temperature determined on
the high temperature side at the foot of the peak is given as the
crystallization temperature. Further, where a melting point is
determined by the differential thermal analysis (DTA), a
temperature at the center point of endothermic peak at a
temperature higher than the crystallization temperature is given as
the melting point.
[0018] There is no particular restriction on means for vitrifying a
composition in the vitrification step, as long as a composition
such as a mixture of crystalline solids may be changed to a liquid
or a gas and then converted to an oxide glass which is a solid
lower in temperature than the glass transition temperature without
crystallization. For example, a composition such as a mixture of
crystalline solids is heated, dissolved and rapidly cooled, thereby
making it possible to obtain an oxide glass. Further, the oxide
glass may be obtained by converting a composition such as a mixture
of crystalline solids once into a vapor state using an evaporation
method, sputtering, glow discharge or the like. Still further, the
oxide glass may also be obtained through conversion to a gel state
using the sol-gel method etc.
[0019] Means for retaining an oxide glass in the reheating step
thereof at a temperature range higher than the glass transition
temperature or the crystallization temperature but lower than the
melting point is that in which, for example, an electrical furnace
or the like is in advance set to be a reheating temperature and the
oxide glass is put into the furnace when a temperature inside the
furnace is kept constant, the oxide glass is immediately taken out
from the electrical furnace or the like after elapse of a target
time and cooled by using a fluid such as air, water or iced water,
cooled copper plate or stainless steel plate, or a roller made with
copper or stainless steel etc. Alternatively, used is a means in
which after the oxide glass is reheated for a predetermined time
inside a furnace such as an electrical furnace, a temperature
inside the furnace is gradually lowered or the oxide glass is
placed away from a heat source inside the furnace by inches,
thereby allowing the oxide glass to stand to cool inside the
furnace. In order to effect reheating, an inert gas atmosphere
etc., such as air, nitrogen, argon or the like is realized inside
the furnace.
[0020] Retention time in the reheating step may be set to be
optimum, whenever necessary, so that an oxide glass after the
reheating step is increased in electric conductivity. The retention
time varies depending on a constitution of the oxide glass, heat
capacity and reheating temperature and is set to be 1 to 180
minutes, for example. Where the retention time is shorter than one
minute, the electric conductivity is increased to a slight extent
due to a small thermal energy given to the oxide glass, and there
is found a variance in increase. Where it is longer than 180
minutes, crystallization or fusing is found to result in a decrease
in electric conductivity, thereby reducing the productivity.
Neither of these cases is preferable.
[0021] Where an oxide glass is heated at a temperature lower than
the crystallization temperature of the oxide glass in the reheating
step, the electric conductivity is increased to a slight extent due
to a small thermal energy given to the oxide glass, and such a
tendency is found that the increase in electric conductivity easily
varies. Further, where the oxide glass is heated at a temperature
lower than the glass transition temperature of the oxide glass in
the reheating step, it is impossible to remove the distortion of
glass skeleton or to reduce the electron hopping activation energy
(band gap). As a result, it is difficult to increase the electric
conductivity. Where the oxide glass is heated at a temperature
higher than the melting point of the oxide glass, the oxide glass
is accelerated for fusing and crystallization to result in a
decrease in electric conductivity. Therefore, neither of the cases
is preferable.
[0022] The electric conductivity of oxide glass (conductive glass)
at a room temperature of 25.degree. C. may be determined, for
example, by a direct current two electrodes method or by a direct
current four electrodes method in which silver paste is applied to
a specimen made with a glass piece, the thickness of which is 1 mm
or lower, dried and silver-containing solder is then used to form
electrodes.
[0023] The electric conductivity of oxide glass (conductive glass)
at 25.degree. C. before the reheating step is in a range from
10.sup.-8 to 10.sup.-4 Scm.sup.-1, preferably from 10.sup.-6 to
10.sup.-4 Scm.sup.-1. There is found a tendency that as the
electric conductivity becomes lower than 10.sup.-6 Scm.sup.-1, it
is more difficult to increase the electric conductivity to a
practical level even after the reheating step. Where the electric
conductivity is lower than 10.sup.-8 Scm.sup.-1, this tendency is
made more conspicuous, which is, therefore, not preferable. Where
the electric conductivity of oxide glass before the reheating step
is made higher than 10.sup.-4 Scm.sup.-1, restrictions are imposed
on the constitution of glass oxides or a temperature history of
vitrification step or the like to result in a lower productivity
and unstable production, which is not preferable either.
[0024] The electric conductivity of oxide glass (conductive glass)
after the reheating step may be improved at a room temperature of
25.degree. C. to a range of 10.sup.-4 to 1 Scm.sup.-1, preferably
from 10.sup.-3 to 1 Scm.sup.-1. Where the conductive glass is
applied to an electrode of a Peltier device, there is found a
tendency that power consumption is increased as the electric
conductivity becomes lower than 10.sup.-3 Scm.sup.-1, which is far
from energy saving. In particular, where the electric conductivity
is lower than 10.sup.-4 Scm.sup.-1, this tendency is made more
conspicuous, which is not preferable.
[0025] In particular, where a conductive glass is that in which an
oxide glass prepared by vitrifying a vanadium-containing
composition is retained and reheated for a predetermined time at a
temperature range higher than the crystallization temperature of
the oxide glass but lower than the melting point, electrons inside
the oxide glass are distributed to a higher level in terms of
energy, thereby it is possible to produce at a room temperature the
conductive glass having high electric conductivity of 10.sup.-1
Scm.sup.-1 or more. Further, only when the conductive glass is
retained at a predetermined temperature range for a short time such
as 30 minutes, it is possible that the electric conductivity is
increased drastically. Still further, if there is a variation in
retention time at a predetermined temperature range, the electric
conductivity is varied to a slight extent, thereby contributing
greatly to a stable production.
[0026] The heating time and the retention time etc., are changed in
the reheating step, by which the conductive glass is designed to
the extent of electric conductivity at a room temperature so as to
be regulated at a high accuracy in a range of 10.sup.-4Scm.sup.-1
or more. The product yield may be, therefore, increased.
[0027] It is noted that the conductive glass may be such that to
which additives such as AgI, NaI, Ag, Ag.sub.2O, In.sub.2O.sub.3,
SnO, SnO.sub.2 are added. This is because the electric conductivity
may be increased by the effect of the additives. Further, in
addition to AgI, NaI, Ag or the like, a reduction preventive agent
such as CeO.sub.2 may be added. It is, thereby, possible to prevent
additives such as AgI, NaI and Ag from being reduced and retain a
higher electric conductivity.
[0028] Further, among three composition systems of vanadium oxide
(V.sub.2O.sub.5), barium oxide (BaO) and iron oxide
(Fe.sub.2O.sub.3) in the oxide glass, the vanadium oxide
(V.sub.2O.sub.5) is from 40 to 98 mol % and preferably from 60 to
85 mol %. As the vanadium oxide (V.sub.2O.sub.5) is lower than 60
mol %, there is found a tendency that it is difficult to retain the
glass skeleton based primarily on vanadium and also difficult to
obtain a higher electric conductivity. As it is greater than 85 mol
%, there is found a tendency that functions of regulating the
electric conductivity and mechanical characteristics etc., by
accessory components are decreased due to a relative decrease in
the amount including the accessory components. In particular, where
it is lower than 40 mol % or it is greater than 98 mol %, these
tendencies are made more conspicuous and therefore not
preferable.
[0029] Among the three composition systems in the oxide glass, the
barium oxide (BaO) is preferable from 1 to 40 mol % and preferably
from 10 to 30 mol %. As it is lower than 10 mol %, there is found a
tendency that it is difficult to attain a homogenous vitrification
and as it is greater than 30 mol %, there is found a tendency that
the mechanical strength is decreased to make the vitrification
difficult. In particular, where it is lower than 1 mol % or it is
greater than 40 mol %, these tendencies are made more conspicuous
and therefore not preferable.
[0030] Among the three composition systems in the oxide glass, the
iron oxide (Fe.sub.2O.sub.3) is preferable from 1 to 20 mol % and
preferably from 5 to 20 mol %. As it is lower than 5 mol %, there
is found a tendency that valence electrons of iron contribute to
electron hopping to a smaller extent, thereby making it difficult
to improve the electric conductivity. As it is lower than 1 mol %,
this tendency is made more conspicuous and therefore not
preferable.
[0031] In particular, where the vanadium oxide (V.sub.2O.sub.5),
the barium oxide (BaO) and the iron oxide (Fe.sub.2O.sub.3) are
respectively in a range from 60 to 85 mol %, from 10 to 30 mol %
and from 5 to 20 mol % in terms of molar ratio, an oxide glass is
reheated, by which the electric conductivity at a room temperature
is increased by more than a few digits to give 10.sup.-1 Scm.sup.-1
or more. It is, therefore, possible to impart excellent properties
to electrical heating elements, materials of various electrodes and
others.
[0032] The conductive glass used in an electrode of a Peltier
device is preferable from 0.1 to 5 mm in thickness. There is found
a tendency that the electrode is decreased in strength and the
electric conductivity is also easily decreased as the conductive
glass is lower than 0.1 mm in thickness. There is found a tendency
that the resistance is increased to make temperature regulation
difficult as it is greater than 5 mm in thickness. These tendencies
are not preferable.
[0033] The temperature regulating container of a second aspect of
the present invention is constituted so as to have a container main
body and the Peltier device as set forth in the first aspect which
is placed on the bottom or the side of the container main body.
[0034] According to the above constitution, the following action is
obtained in addition to the action of the first aspect.
(1) Since the temperature regulating container is provided with the
Peltier device placed on the bottom or the side of the container
main body, it is easier in regulating temperatures, excellent in
cooling efficiency and reliability, and excellent in handleability
and space saving due to the fact that the container main body and
the Peltier device may be handled in an integrated manner.
[0035] In this instance, the conductive glass acting as an
electrode of a heat absorbing portion of the Peltier device is
placed so as to be in contact with the bottom or the side of the
container main body. The container main body may be formed with a
material which will not be corroded by a chemical solution or a
solution accommodated inside and provided with thermal conductivity
sufficient in cooling the chemical solution or the solution
accommodated inside by contacting with the heat absorbing portion
of the Peltier device. For example, preferably used are glass such
as quartz glass and a hard synthetic resin. The container main body
may be formed partially or entirely with the conductive glass.
Where a part of the container main body is formed with the
conductive glass, the bottom or the side may be partially or
entirely formed with the conductive glass to which the
above-described quartz glass, the synthetic resin or the like is
attached, thereby forming the container main body. Alternatively,
the conductive glass may be attached or film-formed on the outer
surface of the inner wall portion formed with the above-described
quartz glass, the synthetic resin or the like.
[0036] Since the conductive glass may be subjected to fine
processing by a focused ion beam processing or the like, the
container main body may be easily processed according to a partial
or an entire configuration thereof and therefore excellent in
productivity.
[0037] The invention of a third aspect is the temperature
regulating container as set forth in the second aspect, in which
the container main body is constituted so as to be at least
partially formed with the conductive glass.
[0038] According to the above constitution, the following actions
are obtained in addition to the action of the second aspect.
(1) Since the container main body is at least partially formed with
a conductive glass, it is possible to improve the thermal
conductivity and chemical resistance. Therefore, the container main
body is able to preserve various chemical solutions or solutions
and effectively heat or cool them by heating means or a Peltier
device and excellent in versatility and reliability. (2) Since the
container main body is formed with a conductive glass, it may be
subjected to fine processing by a processing method such as a
focused ion beam. The thus processed container main body is
excellent in configuration flexibility, easy in miniaturization
thereof and excellent in space saving.
[0039] In this instance, where the container main body is partially
formed with a conductive glass, in particular, the bottom or the
side to be heated or cooled by heating means or a Peltier device is
at least partially formed with a conductive glass, it is possible
to attain an effective heat transfer between the heating means or
the Peltier device and a chemical solution or a solution
accommodated inside the container main body, heating and cooling
efficiency are made excellent.
[0040] The heating means may include any heaters capable of heating
selectively the container main body, and those with a heat element
or the like are preferably used for this purpose. One or more of
the heating means or Peltier devices are placed on the bottom or
the side of the container main body, thereby making it possible to
effect heating or cooling in a simple manner.
[0041] The container main body is preferably provided with a
temperature sensor such as a thermocouple. The temperature sensor
is used to measure the temperature of the container main body or
that of a chemical solution or a solution accommodated inside the
container main body, and a controller is used to control the
driving of heating means or a Peltier device on the basis of the
measurement values, thereby making it possible to retain any given
temperature at a high accuracy.
[0042] It is noted that the conductive glass which forms the
container main body is similar to that used in forming an electrode
of the Peltier device.
[0043] The invention of a forth aspect is the temperature
regulating container as set forth in the third aspect, in which the
electrode of the heat absorbing portion of the Peltier device is
constituted so as to be the conductive glass which forms at least a
part of the container main body.
[0044] According to the above constitution, the following action is
obtained in addition to the actions of the third aspect.
(1) Since the electrode of the heat absorbing portion of the
Peltier device is the conductive glass which forms at least a part
of the container main body, it is possible to easily form the
container main body with the Peltier device in an integrated
manner. It is also possible to securely cool the container main
body which is very small and also securely prevent the electrode
from corrosion resulting from chemicals or dew condensation etc.,
thereby making the Peltier device excellent in reliability and
durability.
[0045] In this instance, the conductive glass, which acts as the
electrode of the heat absorbing portion of the Peltier device,
forms at least apart of the container main body and may be directly
in contact with a chemical solution or a solution accommodated
inside the container main body. Alternatively, the above-described
quartz glass, the synthetic resin or the like may be used to form
an inner wall portion and laminated on the outer surface thereof.
In particular, where the conductive glass acting as the electrode
of the heat absorbing portion of the Peltier device is constituted
so as to be directly in contact with a chemical solution or a
solution accommodated inside the container main body, cooling
efficiency is made excellent, the chemical resistance of the
container main body may be improved, various types of solutions may
be better preserved, the durability and service life are made
excellent.
[0046] The invention of a fifth aspect is the temperature
regulating container as set forth in any one of the second aspect
to the forth aspect and constituted so as to have heating means
placed on the bottom or the side of the container main body.
[0047] According to the above constitution, the following actions
are obtained in addition to the action as set forth in any one of
the second aspect to the forth aspect.
(1) Since the heating means is placed on the bottom or the side of
the container main body, heating efficiency and reliability are
made excellent. Further, since the container main body and the
heating means may be handled in an integrated manner, the
handleability and space saving are made excellent. (2) Both the
Peltier device and the heating means are assembled in the container
main body, by which the container main body may be regulated to a
desired temperature in a short time. Therefore, the versatility and
handleability are made excellent.
[0048] In this instance, those using the above-described heat
element or the like are preferably used as the heating means.
[0049] The invention of a sixth aspect is the temperature
regulating container as set forth in the fifth aspect, in which the
heat element of the heating means is constituted so as to be the
conductive glass which forms at least a part of the container main
body.
[0050] According to the above constitution, the following action is
obtained in addition to the action of the fifth aspect.
(1) Since the heat element of the heating means is the conductive
glass which forms at least a part of the container main body, it is
possible to easily form the container main body with the heating
means in an integrated manner. It is also possible to securely heat
the container main body which is very small, thereby securely
preventing the heat element from deterioration. Therefore, the
heating means is made excellent in reliability and durability.
[0051] In this instance, although the conductive glass acting as
the heat element of the heating means forms at least a part of the
container main body, it may be constituted so as to be directly in
contact with a chemical solution or a solution accommodated inside
the container main body. Alternatively, the above-described quartz
glass, the synthetic resin or the like may be used to form an inner
wall portion and laminated on the outer surface thereof. In
particular, where the conductive glass acting as the heat element
of the heating means is constituted so as to be directly in contact
with a chemical solution or a solution accommodated inside the
container main body, heating efficiency is made excellent, the
chemical resistance of the container main body is improved, various
types of solutions are better preserved, the durability and service
life are made excellent.
[0052] The invention of a seventh aspect is the temperature
regulating container as set forth in the sixth aspect which is
constituted so as to have an insulation portion for insulating the
conductive glass acting as the electrode of the heat absorbing
portion of the Peltier device and the conductive glass acting as
the heat element of the heating means.
[0053] According to the above constitution, the following action is
obtained in addition to the action of the sixth aspect.
(1) Provided is the insulation portion for insulating the
conductive glass acting as the electrode of the heat absorbing
portion of the Peltier device and the conductive glass acting as
the heat element of the heating means. Therefore, where the Peltier
device and the heating means are driven at the same time, the
temperature regulating container is free from any defect and
excellent in reliability and safety.
[0054] In this instance, the insulation portion may be formed with
any material as long as it is able to insulate the conductive glass
and another conductive glass and resistant to a chemical solution
or a solution accommodated inside the container main body. The
previously-described quartz glass or the like is in particular
preferably used.
[0055] The invention of a eighth aspect is the temperature
regulating container as set forth in any one of the third aspect to
the seventh aspect, in which the conductive glass is constituted so
as to be film-formed on the outer surface of the container main
body.
[0056] According to the above constitution, the following action is
obtained in addition to the action of any one of the third aspect
to the seventh aspect.
(1) Since the conductive glass is film-formed on the outer surface
of the container main body, it is possible to control the film
thickness easily and also to effect heating and cooling uniformly
and evenly. Therefore, the container main body is made excellent in
stably retaining temperatures.
[0057] In this instance, as the method in which the conductive
glass may be film-formed on the outer surface of the container main
body, preferably used are sputtering, spin coating or brush coating
etc. As described above, the quartz glass, the synthetic resin or
the like is used to form the inner wall portion of the container
main body and the conductive glass may be film-formed on the outer
surface thereof.
[0058] Sputtering or spin coating may form the conductive glass
thinly and evenly, which is efficient in heating and cooling.
Further, brush coating may form a thick-filmed conductive glass in
a short time, which is excellent in mass production.
EFFECTS OF THE INVENTION
[0059] As described so far, the Peltier device of the present
invention and the temperature regulating container equipped with
the Peltier device are able to provide the following advantageous
effects.
[0060] According to the invention of the first aspect, the
following effect is obtained.
(1) The electrode formed with a conductive glass consisting
primarily of vanadate is used, thereby it is possible to provide
the Peltier device which is easy in temperature regulation, capable
of making a minute regulation of temperatures, excellent in stably
retaining temperatures, capable of securely preventing the
electrode from corrosion resulting from chemicals or dew
condensation etc., excellent in stability of cooling performance,
and excellent in reliability and durability of the electrode.
[0061] According to the invention of the second aspect, the
following effect is obtained.
(1) The Peltier device is placed on the bottom or the side of the
container main body, thereby it is possible to provide the
temperature regulating container easy in temperature regulation,
excellent in stability of cooling action and reliability. Further,
the temperature regulating container is excellent in handleability
and space saving because the container main body and the Peltier
device may be handled in an integrated manner.
[0062] According to the invention of the third aspect, the
following effects are obtained in addition to the effect described
in the second aspect.
(1) The container main body formed with a conductive glass is able
to provide the temperature regulating container excellent in
thermal conductivity and chemical resistance, capable of preserving
various types of chemical solutions or solutions to effectively
heat or cool at a temperature regulating portion, and excellent in
versatility and reliability. (2) The conductive glass is processed
by using a processing method such as a focused ion beam or the
like, thereby it is possible to provide the temperature regulating
container capable of forming a very small container main body,
excellent in configuration flexibility, easy in miniaturizing the
container main body and excellent in space saving.
[0063] According to the invention of the forth aspect, the
following effect is obtained in addition to the effect of the third
aspect.
(1) The conductive glass which forms at least a part of the
container main body is allowed to act as the electrode of the heat
absorbing portion of the Peltier device, thereby it is possible to
provide the temperature regulating container capable of securely
cooling the container main body which is very small, improving the
handleability and cooling efficiency by handling the container main
body and the Peltier device in an integrated manner, securely
preventing the electrode from corrosion resulting from chemicals or
dew condensation etc., and excellent in reliability and
durability.
[0064] According to the invention of the fifth aspect, the
following effect is obtained in addition to the effect described in
any one of the second aspect to the forth aspect.
(1) It is possible to provide the temperature regulating container
capable of selectively heating or cooling the container main body
by using the Peltier device and the heating means, and regulating
the container main body at a desired temperature in a short time,
and excellent in versatility and handleability.
[0065] According to the invention of the sixth aspect, the
following effect is obtained in addition to the effect of the fifth
aspect.
(1) The conductive glass which forms at least a part of the
container main body is allowed to act as the heat element of the
heating means, thereby it is possible to provide the temperature
regulating container capable of securely heating the container main
body which is very small, improving the handleability and heating
efficiency by handling the container main body and the heating
means in an integrated manner, securely preventing the heat element
from deterioration, and excellent in reliability and
durability.
[0066] According to the invention of the seventh aspect, the
following effect is obtained in addition to the effect of the sixth
aspect.
(1) The conductive glass acting as the electrode of the heat
absorbing portion of the Peltier device and the conductive glass
acting as the heat element of the heating means are insulated by
the insulation portion, thereby it is possible to provide a
temperature regulating container which is free from any defect and
excellent in reliability and safety where the Peltier device and
the heating means are driven at the same time.
[0067] According to the invention of the eighth aspect, the
following effect is obtained in addition to the effect of any one
of the third aspect to the seventh aspect.
(1) It is possible to provide the temperature regulating container
easy in controlling the film thickness of the conductive glass
film-formed on the outer surface of the container main body,
excellent in mass production, capable of effecting heating or
cooling uniformly and evenly, and excellent in stably retaining
temperatures of the container main body.
BRIEF DESCRIPTION OF DRAWINGS
[0068] FIG. 1 is a side pattern diagram showing the Peltier device
of Embodiment 1.
[0069] FIG. 2A is a plan view showing a temperature regulating
container equipped with the Peltier device of Embodiment 1 and FIG.
2B is an end elevational view taken along line A-A in FIG. 2A.
[0070] FIG. 3A is a plan view showing the temperature regulating
container of Embodiment 2 and FIG. 3B is an end elevational view
taken along line B-B in FIG. 3A.
[0071] FIG. 4A is a plan view showing the temperature regulating
container of Embodiment 3 and FIG. 4B is an end elevational view
taken along line C-C in FIG. 4A.
[0072] FIG. 5 is the results of differential thermal analyses made
for oxide glasses in Experimental Examples 1 to 3.
[0073] FIG. 6 is a graph for plotting the electric conductivity
before and after reheating of the oxide glasses of Experimental
Examples 1 to 3 which were cooled down to less than the glass
transition temperature.
[0074] FIG. 7 is a graph showing a relationship between the
reheating temperature of the oxide glass of Experimental Example 2,
the reheating time and the electric conductivity.
DESCRIPTION OF REFERENCE NUMERALS
[0075] 1, 1a Peltier device [0076] 2 electrode [0077] 3a N-type
thermoelectric semiconductor [0078] 3b P-type thermoelectric
semiconductor [0079] 4a, 4b electrodes [0080] 5, 16 variable
voltage applying portion [0081] 10, 10a, 10b temperature regulating
container [0082] 11, 12, 22 container main body [0083] 12a inner
wall portion [0084] 12b, 12c, 22b, 22c peripheral wall portions
[0085] 12d, 22d insulation portion [0086] 15 heating means [0087]
22a bottom [0088] 30 temperature sensor [0089] 30a temperature
sensor fixing portion
BEST MODE FOR CARRYING OUT THE INVENTION
Embodiment 1
[0090] An explanation will be made for the Peltier device of
Embodiment 1 of the present invention by referring to the following
drawings.
[0091] FIG. 1 is a side pattern diagram showing the Peltier device
of Embodiment 1.
[0092] In FIG. 1, reference numeral 1 denotes the Peltier device of
Embodiment 1 of the present invention, 2 denotes the electrode of
the heat absorbing portion of the Peltier device 1 formed with a
conductive glass consisting primarily of vanadate, 3a denotes an
N-type thermoelectric semiconductor of the Peltier device 1, one
end of which is coupled to the electrode 2 of the heat absorbing
portion, 3b denotes a P-type thermoelectric semiconductor of the
Peltier device 1, one end of which is coupled to the electrode 2 of
the heat absorbing portion, 4a and 4b denote electrodes of heat
releasing portions of the Peltier device 1 coupled respectively to
the other ends of the N-type thermoelectric semiconductor 3a and
the P-type thermoelectric semiconductor 3b formed with the
conductive glass, and 5 denotes a variable voltage applying portion
of the Peltier device 1 for controlling variably direct current
flowing from the N-type thermoelectric semiconductor 3a to the
P-type thermoelectric semiconductor 3b.
[0093] The conductive glass which forms the electrode 2 of the heat
absorbing portion and the electrodes 4a, 4b of the heat releasing
portion is an oxide-based glass composition containing vanadium,
barium and iron and formed so as to be 3 mm in thickness, with the
electric conductivity at a room temperature being from 10.sup.-4 to
10.sup.-1 Scm.sup.-1.
[0094] After a powder mixture containing vanadium oxide
(V.sub.2O.sub.5) of 60 to 85 mol %, barium oxide (BaO) of 10 to 30
mol % and iron oxide (Fe.sub.2O.sub.3) of 5 to 20 mol % was heated
and fused in a platinum crucible or the like, the resultant was
rapidly cooled and vitrified. Then, the thus prepared glass
composition was retained for a predetermined time at an annealing
processing temperature higher than the crystallization temperature
but lower than the melting point, thereby regulating the electric
conductivity.
[0095] An explanation will be made for the thus formed temperature
regulating container equipped with the Peltier device of Embodiment
1 by referring to the following drawings.
[0096] FIG. 2A is a plan view showing a temperature regulating
container equipped with the Peltier device of Embodiment 1, and
FIG. 2B is an end elevational view taken along line A-A in FIG.
2A.
[0097] In FIG. 2, reference numeral 10 denotes a temperature
regulating container equipped with the Peltier device 1 of
Embodiment 1 of the present invention, 11 denotes a container main
body of the temperature regulating container 10 formed with quartz
glass or the like, 30 denotes a temperature sensor for a
thermocouple or the like of the temperature regulating container 10
for measuring temperatures of a chemical solution or a solution
accommodated inside the container main body 11 fixed on the bottom
of the container main body 11, and 30a denotes a temperature-sensor
fixing portion for fixing the temperature sensor 30 to the
container main body 11.
[0098] A thermal-conductive adhesive agent was used to fix the
electrode 2 of the heat absorbing portion of the Peltier device 1
on the side of the container main body 11, thereby suppressing the
reduction in thermal conductivity.
[0099] An explanation will be made for a method for using the thus
constituted temperature regulating container equipped with the
Peltier device.
[0100] First, a chemical solution or an aqueous solution to be
observed or measured is accommodated inside the container main body
11. The temperature sensor 30 is used to measure temperatures of
the chemical solution or the solution accommodated inside the
container main body 11, then, the controller (not illustrated) is
used to control the driving of the Peltier device 1 on the basis of
the measured values, thereby cooling and retaining the chemical
solution or the solution at any given temperature.
[0101] Where the temperature measured by the temperature sensor 30
is in a permissible range of reference set temperatures, the
Peltier device 1 will not be driven. Where the temperature is in
excess of the permissible range, electric current is controlled at
the variable voltage applying portion 5 of the Peltier device 1,
cooling is effected so that the temperature of the container main
body 11 is in the permissible range of reference set
temperatures.
[0102] The present embodiment is constituted so as to have one unit
of the Peltier device 1 on the side of the container main body 11.
However, the Peltier device 1 may be arbitrarily selected for the
arrangement and the number of units.
[0103] Since the Peltier device of Embodiment 1 is constituted as
described above, the following actions are obtained.
(1) The electrode 2 of the heat absorbing portion is formed with a
conductive glass consisting primarily of vanadate, thereby making
it possible to cool a target substance by changing temperatures
slowly. Thus, the target substance is easy in regulating
temperatures, capable of retaining temperatures at a high accuracy
approximately to a constant level and excellent in stability of
cooling temperatures. (2) Since the electrodes 2, 4a, 4b of the
Peltier device 1 are formed with a conductive glass consisting
primarily of vanadate, it is possible to securely prevent the
electrodes 2, 4a, 4b from corrosion resulting from chemicals or dew
condensation etc. Further, the electrodes 2, 4a, 4b are made
excellent in reliability and durability.
[0104] Since the temperature regulating container equipped with the
Peltier device of Embodiment 1 is constituted as described above,
the following action is obtained.
(1) Since the temperature regulating container is provided with the
Peltier device 1 placed on the side of the container main body 11,
it is easy in regulating temperatures, excellent in cooling
efficiency and reliability, and excellent in handleability and
space saving due to the fact that the container main body 11 and
the Peltier device 1 may be handled in an integrated manner.
Embodiment 2
[0105] FIG. 3A is a plan view showing the temperature regulating
container of Embodiment 2, and FIG. 3B is an end elevational view
taken along line B-B in FIG. 3A. It is noted that the components
that are identical to or similar to those of Embodiment 1 are given
the same reference numerals, and the description thereof is
omitted.
[0106] In FIG. 3, the temperature regulating container 10a of
Embodiment 2 is different from Embodiment 1 in that the container
main body 12 is provided with an insulating inner wall portion 12a
formed with quartz glass or the like and peripheral wall portions
12b, 12c film-formed with a conductive glass consisting primarily
of vanadate on the outer surface of the inner wall portion 12a by
sputtering, the peripheral wall portions 12b, 12c are divided
laterally and insulated by an insulation portion 12d formed with a
material similar to the inner wall portion 12a, and heating means
15 is provided which is placed on the side of the container main
body 12, with the peripheral wall portion 12c formed with the
conductive glass given as a heat element. The conductive glass
which forms the peripheral wall portion 12b of the container main
body 12 acts as an electrode of the heat absorbing portion of a
Peltier device 1a, by which the Peltier device 1a is formed
integrally with the container main body 12.
[0107] It is noted that reference numeral 16 denotes a variable
voltage applying portion of the heating means 15 for variably
controlling direct current which runs through the conductive glass
12c.
[0108] An explanation will be made for a method for using the thus
constituted temperature regulating container.
[0109] First, a chemical solution or an aqueous solution to be
observed or measured is accommodated inside the container main body
12. The temperature sensor 30 is used to measure temperatures of
the chemical solution or the solution accommodated inside the
container main body 12, then, the controller (not illustrated) is
used to control the driving of the Peltier device 1a and that of
the heating means 15 on the basis of the measured values, thereby
regulating and retaining the chemical solution or the solution at
any given temperature.
[0110] Where the temperature measured by the temperature sensor 30
is in a permissible range of reference set temperatures, the
Peltier device 1a and the heating means 15 will not be driven.
Where the temperature is higher than the permissible range,
electric current is controlled at the variable voltage applying
portion 5 of the Peltier device 1a to cool the container main body
12. Where the temperature is lower than the permissible range,
electric current is controlled at the variable voltage applying
portion 16 of the heating means 15 to heat the container main body
12. These motions are repeated, thereby the temperature of the
container main body 12 is regulated so as to be in the permissible
range of the reference set temperatures.
[0111] The material of the insulation portion 12d is not limited to
that used in the present embodiment. Any material may be used as
long as it is able to insulate the peripheral wall portions 12b and
12c and is resistant to a chemical solution or a solution
accommodated inside the container main body 12. Further, in the
present embodiment, the left and right peripheral wall portions
12b, 12c are divided by the insulation portion 12d for insulation.
However, the peripheral wall portion may be arbitrarily selected
for the number of divisions and the divided position. For example,
the peripheral wall portion may be vertically divided to which the
Peltier device 1a and the heating means 15 are respectively
placed.
[0112] The present embodiment is constituted so as to have one unit
of the Peltier device 1a and one unit of the heating means 15 on a
plane to which the container main body 12 faces. However, the
Peltier device 1a and the heating means 15 may be arbitrarily
selected for the arrangement and the number of units.
[0113] It is noted that the temperature-sensor fixing portion 30a
may be formed integrally with the insulation portion 12d or may be
formed by another insulating member.
[0114] Since the temperature regulating container equipped with the
Peltier device of Embodiment 2 is constituted as described above,
the following actions are obtained in addition to the action of
Embodiment 1.
(1) Since the peripheral wall portions 12b, 12c of the container
main body 12 are formed with a conductive glass, it is possible to
improve the thermal conductivity. Therefore, the temperature
regulating container is able to preserve various types of chemical
solutions or solutions and effectively heat and cool them at the
temperature regulating portion and is excellent in versatility and
reliability. (2) Since the electrode of the heat absorbing portion
of the Peltier device 1a is a peripheral wall portion 12b of the
container main body 12 formed with the conductive glass, it is
possible to easily form the container main body 12 with the Peltier
device 1a in an integrated manner. It is also possible to securely
cool the container main body 12 which is very small and also
securely prevent the electrode from corrosion resulting from
chemicals or dew condensation etc., thereby making the Peltier
device 1a excellent in reliability and durability. (3) Since the
heating means 15 is placed on the side of the container main body
12, it is possible to heat the container main body 12 simply and
securely. Therefore, heating efficiency and reliability are made
excellent. (4) Since the heat element of the heating means 15 is
the peripheral wall portion 12c of the container main body 12
formed with a conductive glass, it is possible to easily form the
container main body 12 with the heating means 15 in an integrated
manner. It is also possible to securely heat the container main
body 12 which is very small, thereby securely preventing the heat
element from deterioration. Therefore, the heating means 15 is made
excellent in reliability and durability. (5) Both the Peltier
device 1a and the heating means 15 are assembled in the container
main body 12, by which the container main body 12 may be regulated
to a desired temperature in a short time. Therefore, the
versatility and handleability are made excellent. (6) There is
provided the insulation portion 12d for insulating the peripheral
wall portion 12b made with a conductive glass acting as the
electrode of the heat absorbing portion of the Peltier device 1a
and the peripheral wall portion 12c made with a conductive glass
acting as the heat element of the heating means 15, by which the
temperature regulating container is free from any defect and
excellent in reliability and safety where the Peltier device 1a and
the heating means 15 are driven at the same time. (7) Since the
conductive glass which forms the peripheral wall portions 12b, 12c
consists primarily of vanadate, the electrical conductivity may be
increased to effect cooling by the Peltier device 1a and improve
heating efficiency by the heating means 15. Therefore, the
temperature regulating container is excellent in energy saving. (8)
Since the peripheral wall portions 12b, 12c made with the
conductive glass are film-formed on the outer surface of the inner
wall portion 12a of the container main body 12, it is possible to
control the film thickness of the peripheral wall portions 12b, 12c
easily and also to effect heating and cooling uniformly and evenly.
Therefore, the container main body 12 is made excellent in stably
retaining temperatures.
Embodiment 3
[0115] FIG. 4A is a plan view showing the temperature regulating
container of Embodiment 3, and FIG. 4B is an end elevational view
taken along the line C-C in FIG. 4A. It is noted that the
components that are identical to or similar to those of Embodiment
2 are given the same reference numerals, and description thereof is
omitted.
[0116] In FIG. 4, the temperature regulating container 10b of
Embodiment 3 is different from Embodiment 2 in that the container
main body 22 is provided with an insulating bottom 22a formed with
quartz glass or the like and peripheral wall portions 22b, 22c
formed with the conductive glass similar to that of Embodiment 2,
and the peripheral wall portions 22b, 22C are divided laterally by
the insulation portion 22d formed with a material similar to that
of the bottom 22a for insulation.
[0117] A method for using the temperature regulating container of
Embodiment 3 is similar to that of Embodiment 2, and the
description thereof is be omitted.
[0118] Since the temperature regulating container of Embodiment 3
is constituted as described above, the following actions are
obtained in addition to the action of Embodiment 3.
(1) Since the peripheral wall portions 22b, 22c of the container
main body 22 are formed with conductive glass, they may be
subjected to fine processing by using a processing method such as a
focused ion beam and excellent in configuration flexibility, easy
in miniaturizing the container main body 22 and excellent in space
saving. (2) Since the conductive glass consists primarily of
vanadate, there is provided the container main body 22 which may be
easily formed into a complicated configuration, excellent in
processability and available in various forms. The container main
body 22 is also easily made small in size and light in weight and
therefore excellent in resource saving and mass production.
EXAMPLES
[0119] Hereinafter, a description will be made more specifically
for the present invention by referring to examples. It is noted
that the present invention shall not be limited to these
examples.
Experimental Example 1
[0120] Respective reagents (special grade) were weighed so that
barium oxide (BaO) was 10 mol %, divanadium pentaoxide
(V.sub.2O.sub.5) was 80 mol % and di-iron trioxide
(Fe.sub.2O.sub.3) was 10 mol %, that is, a total of 10 g, and mixed
in an agate mortar. Thereafter, the resultant was placed in a
platinum crucible, and the mixture in the platinum crucible was
heated in an electric furnace, the temperature of which was
elevated to 1,000.degree. C. for 90 minutes in the atmosphere and
fused. A fused material was allowed to flow on a 10 mm-thick
stainless steel plate and rapidly cooled to a temperature lower
than the glass transition temperature, thereby obtaining the oxide
glass of Experimental Example 1.
Experimental Example 2
[0121] The oxide glass of Experimental Example 2 was obtained by
procedures similar to those of Experimental Example 1 except that
respective reagents (special grade) were weighed so that barium
oxide (BaO) was 20 mol %, divanadium pentaoxide (V.sub.2O.sub.5)
was 70 mol % and di-iron trioxide (Fe.sub.2O.sub.3) was 10 mol %,
that is, a total of 10 g.
Experimental Example 3
[0122] The oxide glass of Experimental Example 3 was obtained by
procedures similar to those of Experimental Example 1 except that
respective reagents (special grade) were weighed so that barium
oxide (BaO) was 30 mol %, divanadium pentaoxide (V.sub.2O.sub.5)
was 60 mol % and di-iron trioxide (Fe.sub.2O.sub.3) was 10 mol %,
that is, a total of 10 g.
(Results of Differential Thermal Analysis of Oxide Glasses of
Experimental Examples 1 to 3)
[0123] Differential thermal analysis (DTA) was made for the oxide
glasses of Experimental Example 1 to 3. More particularly, the
differential thermal analysis (DTA) was made at a temperature
elevating rate of 10.degree. C./min in a nitrogen atmosphere, with
.alpha. aluminium oxide used as a reference material.
[0124] FIG. 5 shows the results of differential thermal analysis of
the oxide glasses of Experimental Examples 1 to 3.
[0125] As shown in FIG. 5, the glass transition temperature (Tg)
and the crystallization temperature (Tc) were increased with an
increase in the molar ratio of barium oxide and a decrease in the
molar ratio of divanadium pentaoxide. The crystallization
temperature Tc was 362.degree. C. in Experimental Example 1,
392.degree. C. in Experimental Example 2 and 433.degree. C. in
Experimental Example 3. A sharp endothermic peak found at a
temperature range exceeding the crystallization temperature (Tc)
was suggestive of a melting point, and the melting point was
600.degree. C. or higher in Experimental Example 1, 540.degree. C.
in Experimental Example 2 and 563.degree. C. in Experimental
Example 3.
(Relationship Between Reheating Temperature and Electric
Conductivity)
[0126] The oxide glasses of Experimental Examples 1 to 3 cooled to
a temperature lower than the glass transition temperature were
reheated for one hour in an atmosphere at the respective
temperatures of 350.degree. C., 400.degree. C., 500.degree. C. and
550.degree. C., thereby the electric conductivity of the oxide
glasses before and after reheating was measured at 25.degree. C. by
a direct current four-electrode method.
[0127] FIG. 6 is a graph for plotting the electric conductivity
before and after reheating of the oxide glasses of Experimental
Examples 1 to 3 cooled to a temperature lower than the glass
transition temperature. In FIG. 6, the horizontal axis indicates
the reheating temperature (.degree. C.), while the longitudinal
axis indicates the electric conductivity .sigma. (Scm.sup.-1) at
25.degree. C.
[0128] As shown in FIG. 6, where the oxide glass of Experimental
Example 1 was reheated for one hour at 500 to 550.degree. C., a
temperature range in excess of the crystallization temperature
(362.degree. C.) but lower than the melting point (600.degree. C.
or higher), the electric conductivity at 25.degree. C. could be
increased by approximately four digits as compared with the
conductivity before reheating.
[0129] The electric conductivity reheated for one hour at
400.degree. C. in FIG. 6 remained unchanged as compared with that
before reheating. However, after reheating for two hours at
400.degree. C., the electric conductivity at a room temperature
(25.degree. C.) could be increased to about 10.sup.-3 Scm.sup.-1.
In the oxide glass of Experimental Example 1, one-hour retention
time at the reheating temperature of 400.degree. C. was thought to
be insufficient.
[0130] Further, as shown in FIG. 6, where the oxide glass of
Experimental Example 2 was reheated for one hour at 400 to
500.degree. C., a temperature range in excess of the
crystallization temperature (392.degree. C.) but lower than the
melting point (540.degree. C.), the electric conductivity at
25.degree. C. could be increased to a higher level of 10.sup.-3
Scm.sup.-1 or more. In particular, where the oxide glass was
reheated at 500.degree. C., the electric conductivity could be
increased to a higher level of 10.sup.-1 Scm.sup.-1 or more. It is
noted that where the oxide glass was reheated for one hour at
550.degree. C., a temperature higher than the melting point
(540.degree. C.), it was partially crystallized.
[0131] Still further, as shown in FIG. 6, where the oxide glass of
Experimental Example 3 was reheated at 500.degree. C., a
temperature in excess of the crystallization temperature
(433.degree. C.) but lower than the melting point (563.degree. C.),
the electric conductivity at 25.degree. C. could be increased to a
higher level of 10.sup.-2 Scm.sup.-1 or more.
[0132] Where the oxide glass was reheated for one hour at
550.degree. C., a temperature close to the melting point
(563.degree. C.), it was partially crystallized. Therefore, the
electric conductivity of oxide glass reheated at 550.degree. C. was
not plotted. This crystallization was inferred due to an increased
molar ratio of barium oxide to divanadium pentaoxide. Where the
oxide glass was reheated for a shorter retention time, or 0.5 hours
at 550.degree. C., it was not crystallized. Therefore, the electric
conductivity at 25.degree. C. could be increased to about 10.sup.-2
Scm.sup.-1.
[0133] As described so far, it was apparent that after a reheating
step where the oxide glass (conductive glass) was retained at a
temperature range in excess of the crystallization temperature but
lower than the melting point, the electric conductivity at a room
temperature (25.degree. C.) could be drastically increased.
Further, it was found that the electric conductivity was improved
with an increase in the reheating temperature within a temperature
range at which no crystallization or fusion was found
conspicuously. It was also found that a shorter retention time was
acceptable at a higher reheating temperature. On the basis of these
findings, a mechanism by which the electric conductivity is
improved on reheating at a temperature range in excess of the
crystallization temperature but lower than the melting point is
considered due to activated energy of electrons.
[0134] In addition to these experimental examples, various types of
oxide glasses were prepared so that the molar ratio of vanadium
oxide (V.sub.2O.sub.5), barium oxide (BaO), iron oxide
(Fe.sub.2O.sub.3) would fall under the respective ranges of 40 to
98 mol %, 1 to 40 mol % and 1 to 20 mol %, thereby measuring the
respective crystallization temperatures and melting points to
obtain the electric conductivity at a room temperature before and
after a reheating step. It was confirmed that as with these
experimental examples, the electric conductivity was increased
after the reheating step.
[0135] Further, it was confirmed that the oxide glass produced by
fusing and cooling a mixture of vanadium oxide (V.sub.2O.sub.5),
diphosphate pentaoxide (P.sub.2O.sub.5) and barium oxide (BaO) and
the oxide glass produced by fusing and cooling a mixture of
vanadium oxide (V.sub.2O.sub.5), potassium oxide (K.sub.2O) and
iron oxide (Fe.sub.2O.sub.3) were increased in electric
conductivity after the reheating step, in addition to the oxide
glass produced by fusing and cooling a mixture of vanadium oxide
(V.sub.2O.sub.5), barium oxide (BaO) and iron oxide
(Fe.sub.2O.sub.3).
(Relationship Between Reheating Time and Electric Conductivity)
Example 1
[0136] The oxide glass of Experimental Example 2 cooled to a
temperature lower than the glass transition temperature was
reheated at 500.degree. C., a temperature in excess of the
crystallization temperature (392.degree. C.) but lower than the
melting point (540.degree. C.) in an atmosphere and taken out from
a furnace at every predetermined time, by which the electric
conductivity at 25.degree. C. was measured.
Example 2
[0137] The oxide glass of Experimental Example 2 cooled to a
temperature lower than the glass transition temperature was
reheated at 400.degree. C., a temperature in excess of the
crystallization temperature (392.degree. C.) but lower than the
melting point (540.degree. C.) in an atmosphere, and taken out from
a furnace at every predetermined time, by which the electric
conductivity at 25.degree. C. was measured.
Example 3
[0138] The oxide glass of Experimental Example 2 cooled to a
temperature lower than the glass transition temperature was
reheated at 350.degree. C., a temperature higher than the glass
transition temperature (328.degree. C.) but lower than the
crystallization temperature (392.degree. C.) in an atmosphere, and
taken out from a furnace at every predetermined time, by which the
electric conductivity at 25.degree. C. was measured.
[0139] FIG. 7 is a graph showing a relationship between the
reheating temperature of the oxide glass of Experimental Example 2,
the reheating time and the electric conductivity. In FIG. 3, the
horizontal axis indicates the retention time at a reheating
temperature, while the longitudinal axis indicates the electric
conductivity .sigma. (Scm.sup.-1) at 25.degree. C.
[0140] In Examples 1 and 2 where the oxide glass of Experimental
Example 2 cooled to a temperature lower than the glass transition
temperature was reheated at a temperature in excess of the
crystallization temperature (392.degree. C.) but lower than the
melting point (540.degree. C.) in an atmosphere, it was confirmed
that only 30-minute reheating could increase the electric
conductivity by three digits or more and continuous reheating
barely changed the electric conductivity. It was also confirmed
that Example 1 where the reheating temperature was higher than
Example 2 could increase the electric conductivity.
[0141] On the other hand, in Example 3 where the oxide glass was
reheated at a temperature higher than the glass transition
temperature (328.degree. C.) but lower than the crystallization
temperature (392.degree. C.), it was confirmed that the electric
conductivity was increased with an increase in the retention time
at the reheating temperature and no electric conductivity could be
kept constant unless the oxide glass was retained for 180 minutes
or longer. It was also confirmed that the electric conductivity of
Example 3 was lower by one digit or more than the electric
conductivity of Example 1 and that of Example 2.
[0142] As described so far, according to the present example, the
oxide glass is retained for an appropriate time at a reheating
temperature, according to the reheating temperature, thereby
preventing a variance in electric conductivity. In particular,
according to Examples 1 and 2, only if it is retained at a
predetermined temperature range for a short time, about 30 minutes,
is it possible that the electric conductivity is increased
drastically. Further, it became clear that even if there is any
change in retention time, the electric conductivity is changed to a
slight extent, and the stability of productivity is quite excellent
and preferable. It became also clear that the heating time and
others are changed in a reheating step, by which the extent of
electric conductivity of vanadate glass at a room temperature may
be designed in a range of 10.sup.-4 Scm.sup.-1 or more and
controlled at a high accuracy.
[0143] It has been found that when the thus obtained conductive
glass is used as an electrode of a Peltier device, temperatures may
be set minutely with a gradual change in temperature, a target
substance may be kept accurately at a temperature approximately in
a constant range, and excellent in stability of cooling
performance.
INDUSTRIAL APPLICABILITY
[0144] The present invention is to provide a Peltier device capable
of retaining a certain temperature at a high accuracy by using a
conductive glass consisting primarily of vanadate as an electrode,
easy in temperature regulation and excellent in handleability and
also to provide a temperature regulating container equipped with
the Peltier device which is easy in processing the container main
body, excellent in configuration flexibility, capable of forming a
very small space to accommodate a chemical solution or an aqueous
solution etc., excellent in chemical resistance and preservability,
capable of effectively heating or cooling a very small space at
which the chemical solution or the aqueous solution etc., is
accommodated and retaining it at any given temperature, thereby
making observations and various measurements etc., effectively in a
short time and excellent in reliability, versatility and
workability. Thereby, it is possible to improve the handleability
of a chemical solution or an aqueous solution etc., in industrial
fields such as biotechnology and medicine.
* * * * *