JP5366010B2 - Steam sterilizer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To efficiently evaporate condensed water condensed on the surface of an object to be sterilized in a drying process, to shorten the time needed for the drying process, to save energy and to increase the number of times of sterilization work per day. <P>SOLUTION: In the method of setting the object to be sterilized to a sterilization container in a sterilization method of performing a sterilization process of housing the object 4 to be sterilized put in the sterilization container 3 inside a sterilization tank 1 and sterilizing it by saturated steam and a drying process of drying the object 4 to be sterilized after the sterilization process, the water absorbing member 6 comprising water absorbing paper or nonwoven fabric is spread on the inner bottom surface 5 of the sterilization container 3, and the object 4 to be sterilized is set on the water absorbing member 6. <P>COPYRIGHT: (C)2011,JPO&amp;INPIT

Description

The present invention relates to a steam sterilization apparatus that performs a sterilization process for sterilizing an object to be sterilized with saturated steam and a drying process for drying the object to be sterilized after the sterilization process.

  In general, in a steam sterilizer, it is necessary to dry the condensed water adhering to the surface of the object to be sterilized after the sterilization process and the water remaining at the bottom of the sterilization container containing the object to be sterilized (water remaining after the sterilization process remains). May cause contamination of the object to be sterilized). For this reason, in a steam sterilization apparatus, the drying process is usually set after the sterilization process.

  In general drying process, the steam supply space provided on the outer periphery of the steam sterilizer is maintained at a predetermined pressure, and the sterilization tank is repeatedly depressurized and decompressed while the radiant heat is applied to the object to be sterilized. Thus, the condensed water is dried by evaporating it at a low temperature. In this case, the condensed water adhering to the surface of the object to be sterilized can give evaporation heat to the condensed water by the heat of the object to be sterilized and can be dried. Is the water that has condensed and flowed down on the surface of the object to be sterilized, so there is a problem that the amount of water is large and the surface area of the water droplet is reduced by the surface tension of the water. .

  The applicant has proposed a method for solving this problem in Patent Document 1. The method of Patent Document 1 is a method in which condensed water generated in a sterilization container during a drying process is heated by steam and then vacuumed and dried. In this method, heat can be applied by steam, but since only the condensed water corresponding to the heat is evaporated, there is a problem that the condensed water in the sterilization container that originally existed does not evaporate.

JP 2002-126049 A

  The problem to be solved by the present invention is that the condensed water condensed on the surface of the object to be sterilized is efficiently evaporated in the drying process, shortening the time required for the drying process, thereby saving energy and increasing the number of sterilization operations per day. It is to let you.

This invention was made in order to solve the above-mentioned problem, and the invention according to claim 1 is a sterilization process in which an object to be sterilized placed in a sterilization container is housed in a sterilization tank and sterilized with saturated steam; A steam sterilization apparatus for performing a drying step for drying the object to be sterilized after this sterilization step, wherein a water-absorbing member made of paper or nonwoven fabric having water absorption is laid on the inner bottom surface of the sterilization container, and the sterilization target The sterilization step and the drying step are performed in a state where an object is set on the water absorbent member.

According to the first aspect of the present invention, condensed water adhering to the surface of the object to be sterilized is absorbed by the water absorbing member during the sterilization process, and heat transfer from the container and the object to be sterilized is performed during the drying process. The absorbed condensed water can be efficiently evaporated. Further, since the water-absorbing member is made of paper or non-woven fabric, the thickness per weight can be reduced as compared with a fabric made by knitting or weaving fibers, and the sterilization container and Heat transfer efficiency from the object to be heated to the water absorbing member can be improved, and drying performance can be improved.

  The invention according to claim 2 is characterized in that, in claim 1, the paper or the nonwoven fabric is composed of superabsorbent fibers.

  According to invention of Claim 2, in addition to the effect by the invention of Claim 1, since the highly water-absorbent fiber is used, there exists an effect that water absorption can be improved.

  A third aspect of the present invention is characterized in that in the first or second aspect, the paper or the nonwoven fabric is disposed on the entire inner bottom surface of the sterilization container.

  According to the invention described in claim 3, in addition to the effect of the invention described in claim 1 or 2, since the contact area between the water absorbing member and the sterilization container is wide, the water absorption from the sterilization container. By increasing the heat transfer amount to the conductive member, the heat transfer performance is improved, and the drying performance can be enhanced.

  The invention according to claim 4 is characterized in that, in claims 1 to 3, the paper or the nonwoven fabric is single.

  According to the invention described in claim 4, in addition to the effect of the invention described in claim 1 or 2, the sterilization container is compared with the paper or non-woven fabric in which the number of overlaps is two or more. The heat transfer performance to the water absorbing member can be improved, and the drying performance can be enhanced.

  According to this invention, the condensed water condensed on the surface of the object to be sterilized can be efficiently evaporated in the drying step. As a result, the time required for the drying process can be shortened, thereby saving energy and increasing the number of sterilization operations per day. Moreover, drying performance can be further improved by comprising the said water absorbing member with paper or a nonwoven fabric.

It is a schematic diagram showing a vapor sterilization apparatus of the present invention. It is a partially broken perspective view explaining the state which set the to-be-sterilized thing in this invention to the sterilization container. It is a longitudinal cross-sectional view which illustrates typically the state which set the to-be-sterilized thing in this invention to the sterilization container. It is a top view which illustrates typically the state which set the to-be-sterilized thing in this invention to the sterilization container. It is a figure explaining the pressure change in the sterilization tank of the said sterilizer. It is a figure which shows the comparison result of the drying performance of this invention and the proportionality which used the water absorbing member as the towel. It is a figure which shows the change of the drying performance at the time of changing the number of piles of a water absorbing member.

  Before describing embodiments of the present invention, terms used in the specification of this application will be described. Since the steam sterilization apparatus of the present invention performs sterilization with saturated steam, “steam” means saturated steam unless otherwise specified below. The “substance to be sterilized” does not indicate only what is desired to be sterilized, but includes those in which baskets or sterilization bags are filled with what is desired to be sterilized. When the basket and the sterilization bag are included, the basket and the sterilization bag come into contact with the water absorbing member described later.

  Paper is produced by sticking plant fibers and other fibers, and is produced without weaving or knitting like cloth. Paper is produced with paper flowing in a certain direction on a paper machine, and is made with fibers aligned in the direction of travel, thereby making paper with “paper flow” (paper with fiber orientation). be able to. Non-woven fabric is a fiber sheet, web or vat, in which fibers are oriented in one direction or randomly, and the fibers are joined together by alternating current and / or fusion and / or adhesion. , Excluding knitted fabrics, tufts and shrunk felts.

Next, an embodiment of the present invention will be described. A steam sterilization apparatus according to an embodiment of the present invention includes a sterilization process in which an object to be sterilized placed in a sterilization container is stored in a sterilization tank and sterilized with saturated steam, and after the sterilization process, the object to be sterilized is dried. and the drying step intends line. In the steam sterilization apparatus of this embodiment, a water-absorbing member made of paper or non-woven fabric having water absorption is laid on the inner bottom surface of the sterilization container, and an object to be sterilized is set on the water-absorbing member.

  According to this embodiment, the condensed water adhering to the surface of the object to be sterilized falls during the sterilization process and is absorbed by the water absorbing member. Next, the water-absorbing member is heated by heat transfer from the sterilization container and the object to be sterilized during the drying step, whereby condensed water absorbed by the water-absorbing member evaporates.

  The water absorbing member is heated by holding the sterilization tank wall at a high temperature during the drying process by making the sterilization tank containing the sterilization container into a jacket structure or the like, and radiating heat from the sterilization tank wall to When it is configured to heat, evaporation of condensed water is promoted by this radiant heat.

  Thus, compared to the conventional method of sterilization and drying without laying the water-absorbing member in the sterilization container, the condensed water adhering to the surface of the object to be sterilized can be efficiently evaporated during the sterilization process. .

  Further, since the water-absorbing member is made of paper or non-woven fabric, it has a larger bulk density than a fabric made by knitting or weaving fibers. The air layer in the water absorbing member can be made thin. As a result, heat transfer efficiency from the sterilization container and the material to be sterilized to the water-absorbing member is higher than that in which the water-absorbing member is made of cloth, and the drying performance is improved. It can be carried out.

  When the drying step is performed by combining decompression in the sterilization tank and heating from the sterilization tank wall, energy required for decompression and heating can be saved and energy saving can be realized. Further, by shortening the time of the drying process, a series of sterilization operations can be performed in a short time, and the number of sterilization operations per day can be increased.

Here, the components of this embodiment will be described. The object to be sterilized is not particularly limited, but is typically a medical instrument, and has a metal basket (having a large number of holes through which condensed water generated on the surface of the object to be sterilized passes as described above. ) in and medical machinery and equipment were placed, and includes a medical machines and implements placed in sterilization bags. In many cases, the medical machine instrument includes many metal instruments.

  The sterilization container is preferably made of metal and has an opening on the top surface for taking in and out the article to be sterilized, and can be called a tray.

  The sterilization container is preferably opened / closed to cover the opening in order to prevent the condensed water adhering to the sterilization tank wall from falling into the sterilization container and for hygiene considerations when the sterilization container is moved after the sterilization operation is completed. A free lid is provided, or the entire sterilization container is covered with a surrounding member that does not allow water to pass but allows water to pass. In the case where the lid is used, if the vapor passage hole is not formed of metal in the lid, the vapor passage hole can be formed in the side wall of the sterilization container. Further, when the surrounding member is used, the sterilization container is wrapped with an opaque non-woven fabric as described above, but the sterilization container can be taken in and out, and the sterilization container can be surrounded by what is called a container that can be sealed and a bag. Can do. As the lid and the surrounding member, known ones can be used.

  The sterilization tank can be referred to as a processing tank or a sterilization chamber, and is a hermetically sealed hollow container in which an object to be sterilized is stored and sterilized by saturated steam, and the object to be sterilized is put in and out through an openable / closable door. Is done.

  The water-absorbing member is formed of paper or non-woven fabric, and preferably adheres to the surface of the object to be sterilized from the amount to be sterilized (maximum capacity) accommodated in the sterilization container during the sterilization process. It is comprised so that it may have the absorption performance which can absorb more than condensed water amount (maximum condensed water amount). The maximum amount of condensed water can be obtained by calculation or experiment from the sterilization conditions of the sterilization step, the maximum capacity, and the like.

  The material of the paper or nonwoven fabric is preferably a superabsorbent fiber. Superabsorbent fibers contain water-swellable fibers as the main material. The water-swellable fiber is, for example, a fiber such as cellulose, cotton, rayon, water-absorbing polymer, and is preferably rayon.

  When the water absorbent member is a nonwoven fabric, an adhesive binder is included in addition to the water-swellable fiber. As the adhesive binder, resin powder, core-sheath resin fibers, or the like can be used.

  The water absorbing member is required to have a predetermined water absorption performance and an evaporation performance (drying performance) for evaporating the absorbed water. The water absorption performance is improved by containing a large amount of the water-swellable fiber. Moreover, it is thought that water absorption performance improves also by improving the diffusibility of water. Moreover, it is thought that the diffusibility of water improves by giving directionality to the said water-swellable fiber. For this reason, in this embodiment, in order to improve the diffusibility of the condensed water dropped from the object to be sterilized, preferably, the paper or the nonwoven fabric is provided with the water-swellable fiber having directivity.

Since the evaporation performance depends on heat transfer from the object to be sterilized and the sterilization container,
The heat transfer performance (heat transfer efficiency) from the object to be sterilized and the sterilization container is improved.

  The following conditions can be considered as conditions for improving the heat transfer performance. The first condition is to take a wide contact area between the water-absorbing member and the sterilization container. For this reason, in this embodiment, the water absorbing member is spread over the entire inner bottom surface of the sterilization container. The “entire surface” is preferably 100% of the area of the inner bottom surface (excluding the rising wall) of the sterilization container, but is an area where the sterilized object does not protrude from the water absorbent member, for example, 70% or more. And The water-absorbing member may be laid so as to contact the rising wall, and in this case, it exceeds 100% of the inner bottom surface of the sterilization container.

  The second condition is the number of stacked water absorbing members. When the number of the water-absorbing members is increased, heat transfer from the sterilization container to the upper water-absorbing member is deteriorated, and heat transfer performance is deteriorated. This decrease in heat transfer performance is thought to be due to the fact that an air layer is formed between the stacked water absorbing members, and this air layer becomes an obstacle to heat transfer from the object to be sterilized and the sterilization container. For this reason, the number of the water-absorbing members stacked is preferably single. However, although not preferable from the viewpoint of heat transfer performance, in this embodiment, it is possible to double the water absorption amount of the water absorbing member.

  The third condition is a condition of the structure of the water absorbing member. The heat transfer performance is improved by using paper or a non-woven fabric as the water-absorbing member instead of a cloth such as a towel or linen. Moreover, it can also be improved by increasing the bulk density of the water-absorbing member and reducing the thickness of the water-absorbing member. The reason is considered that heat transfer efficiency improves as a result of being able to thin the air layer in the water-absorbing member in any case. For this reason, in this embodiment, preferably, the thickness of the water absorbing member is set to 1.0 mm or less.

  Furthermore, the drying performance is considered to be improved by aligning the direction of the water-swellable fibers of the water-absorbing member in a predetermined direction. The reason is that during the drying step, the surface of the water-absorbing member (the surface on the side in contact with the object to be sterilized) is in partial contact with the object to be sterilized. Condensed water evaporates. That is, the water-absorbing member has a portion where evaporation has progressed and a portion where evaporation has not progressed. In order to improve the evaporation performance, water from a portion where evaporation has not progressed to a portion where evaporation has progressed can be improved. It is necessary to improve mobility. This water mobility is considered to be improved by aligning the direction of the water-swellable fibers in a predetermined direction.

The steam sterilization apparatus of this embodiment includes at least the sterilization step and the drying step. The sterilization step is performed by supplying steam into the sterilization tank. A steaming space for heating the inside of the sterilization tank is preferably provided around the sterilization tank for performing the sterilization process. The steaming space is provided so as to heat the outer wall of the sterilization tank, and preferably a space formed between the outer wall and the surrounding wall by providing an enclosure wall so as to cover the outer wall of the sterilization tank. (It can also be referred to as a jacket.) However, it can also be constituted by a heat transfer tube arranged along the outer wall of the sterilization tank.

  The drying step is preferably performed by reducing the pressure while heating the inside of the sterilization tank. The heating is preferably performed by supplying steam to the steam supply space. Moreover, the said pressure reduction is performed by operating the pressure reduction means connected to the said sterilization tank. As a method for reducing the pressure, a method in which the pressure reducing means is continuously operated during the drying step to reduce the pressure and a method in which the pressure reducing means is operated intermittently to reduce the pressure can be employed. According to the results of the experiment, it was confirmed that continuous decompression during the drying process is superior in the drying performance.

Furthermore, the steam sterilization apparatus of this embodiment can include steps other than the sterilization step and the drying step as a series of sterilization operations. This process includes a preheating process and an air removal process as a pretreatment process.

Hereinafter, the steam sterilization apparatus of Example 1 of this invention is demonstrated based on drawing. Figure 1 is a schematic diagram showing a vapor sterilization apparatus of the present invention. FIG. 2 is a perspective view illustrating a state where the object to be sterilized is set to a sterile container in the present invention, FIG. 3, the present invention FIG. 4 is a longitudinal cross-sectional view schematically illustrating a state in which an object to be sterilized is set in a sterilization container, and FIG. 4 is a state in which the object to be sterilized in the present invention is set in a sterilization container (a state in which it is not surrounded by an enclosing member) FIG. 5 is a diagram for explaining the pressure change in the sterilization tank of the steam sterilizer, and FIG. 6 is a comparison between the present invention and the water absorbent member as a towel. FIG. 7 is a diagram showing a change in drying performance when the number of superposed water absorbing members is changed.

  In FIG. 1, a steam jacket 2 formed in a double can shape as a steam supply space is provided on the outer wall of the sterilization tank 1, and the sterilization tank 1 is heated from the outside.

Then, the steam sterilization apparatus of Example 1 includes a sterilization process (FIG. 5) in which the object to be sterilized 4 placed in a metal sterilization container 3 having an upper opening is accommodated in the sterilization tank 1 and sterilized with saturated steam (FIG. 5). After this sterilization step, a drying step (FIG. 5) for drying the article to be sterilized 4 is performed. Then, the water-absorbing member 6 is interposed between the article to be sterilized 4 and the inner bottom surface 5 of the sterilization container 3 so as to be in direct contact with the article to be sterilized 4 and the inner bottom surface 5 to perform a sterilization process. Furthermore, condensed water adhering to the object to be sterilized 4 during this sterilization process is absorbed by the water absorbent member 6 and absorbed by the water absorbent member 6 by heat transfer from the object to be sterilized 4 and the sterilization container 3 during the drying process. It is configured to evaporate condensed water.

  In the first embodiment, the water absorbing member 6 is formed of a nonwoven fabric. JP3457 or JP5323 made by Kuraray Laflex Co., Ltd., which is made of superabsorbent fibers and sold as a wet napkin, is used as the material for the nonwoven fabric (JP stands for Japan Products, and the number after JP is Kuraray) This is the No. of the brand of CRAFlex Co., Ltd.). JP3547 is formed from rayon as a water-swelling fiber and heat-sealing fiber (PE / PET) as an adhesive binder. JP5323 is formed of rayon, heat-bonding fibers (PE / PP), and polyester. This heat-fusible fiber has a two-layer structure. The fiber lengths are: rayon: 40 mm, heat-sealing fiber: 51 mm, and polyester: 51 mm. This nonwoven fabric has directionality to the fibers, and improves the diffusibility of the condensed water dropped from the article to be sterilized 4. The non-woven fabric is not limited to the above, and for example, SA-821 manufactured by Hogi Medical Co., Ltd. can be used.

  In this Example 1, in order to improve the heat transfer performance (heat transfer efficiency) from the article to be sterilized 4 and the sterilization container 3, 100% of the water absorbing member 6 is removed from the inner bottom surface (excluding the rising wall) 5 of the sterilization container 3. As an area occupied, it is spread over the inner bottom surface 5. The rising wall around the sterilization container 3 is formed to be inclined slightly outward so that the upper surface opening is widened.

  Further, when the number of the water-absorbing members 6 is increased, the heat transfer from the sterilization container 3 to the upper water-absorbing member is deteriorated and the heat transfer performance is deteriorated. In order to prevent the heat transfer performance from being lowered, The number of water-absorbing members 6 stacked is single. Further, the thickness of the water absorbing member 6 is set to 1.0 mm or less in order to improve the heat transfer performance.

  As shown in FIG. 3, the sterilization container 3 is entirely covered with an enclosing member 7 that does not allow water to permeate but allows vapor to permeate. The surrounding member 7 is an opaque nonwoven fabric.

Next, the steam sterilizer of Example 1 will be described. A first steaming line 8 as a steaming path is connected to the sterilization tank 1, and a second steaming line 9 is connected to the steam jacket 2. The first and second steam supply lines 8 and 9 are respectively provided with first and second valves 10 and 11 as steam supply control means. The first and second steam supply lines 8 and 9 are connected to an original steam supply line (not shown) having a steam source valve (not shown) that is two-position controlled to be fully closed and fully opened. In the first embodiment, a motor valve is used as the first valve 10 to stabilize the temperature in the sterilization tank 1 and improve the sterilization quality, and the second valve 11 is selected to be open and closed to improve operation response and reduce costs. A solenoid valve is used.

  An air supply line 12 is connected to the sterilization tank 1, and aseptic air is supplied into the sterilized tank 1 that has been depressurized, so that the inside of the sterilization tank 1 is restored to atmospheric pressure. The air supply line 12 is provided with a sterile filter 13 and an air supply valve 14 in order from the upstream side.

  Further, a evacuation line 15 is connected to the sterilization tank 1 so that the inside of the sterilization tank 1 is depressurized. The evacuation line 15 is provided with a first exhaust valve 16 and a vacuum pump 17 in order from the upstream side. The exhaust line 18 is branched from the upstream position of the first exhaust valve 16 in the vacuum line 15, and the downstream end thereof is connected to the downstream position of the vacuum pump 17 in the vacuum line 15. The exhaust line 18 serves to discharge the steam in the sterilization tank 1. A second exhaust valve 19 is provided in the exhaust line 18.

The sterilization tank 1 and the steam jacket 2 are provided with first and second pressure sensors 20 , 21 as pressure detection means for detecting respective internal pressures, and a drain discharge port communicating with the sterilization tank 1 of the evacuation line 15. The temperature sensor 22 is provided in the part called. The mounting position of the temperature sensor 22 is selected so as to detect the lowest temperature in the sterilization tank 1 and a portion communicating with the sterilization tank 1.

The first and second pressure sensors 20 , 21 and the temperature sensor 22 are connected to the controller 23 by signal lines. The controller 23 follows the preset control procedure according to the first and second valves 10 and 11, the steam source valve, the air supply valve 14, the first exhaust valve 16, and the second exhaust valve 19. And the operation of the vacuum pump 17 is controlled.

  As shown in FIG. 5, the control procedure is configured to sequentially execute a preheating process, an air exclusion process, a steaming process, a sterilization process, an exhaust process, and a drying process.

  The operation of the first embodiment having the above configuration will be described below according to the operation process. In the preheating process for warming the article to be sterilized 4, the door of the sterilization tank 1 is closed, the steam source valve, the second valve 11, the air supply valve 14 and the second exhaust valve 19 are opened, and steam is introduced into the steam jacket 2. To maintain the inside of the steam jacket 2 at a predetermined pressure. Next, the door of the sterilization tank 1 is opened, and the pre-heating step of heating the sterilization tank 1 by heating the sterilization tank 1 by putting the sterilization object 4 into the sterilization tank 1 is performed. This preheating step is performed for a predetermined time by a timer. In this preheating step, the second valve 11 is controlled by the pressure detected by the second pressure sensor 16, and the inside of the steam jacket 2 is controlled to be the first set value.

  Next, in the air removal step, the air supply valve 14 and the second exhaust valve 19 are closed, the first exhaust valve 16 is opened and the vacuum pump 17 is operated to discharge the air in the sterilization tank 1; One exhaust valve 16 is closed, the vacuum pump 17 is stopped, and the operation of supplying the steam into the sterilization tank 1 by opening the steam source valve and the first valve 10 is repeated several times alternately.

After the air removal process, the process moves to the steaming process. In this steaming process, the first valve 10 is opened,
Steam for heat sterilization is supplied into the sterilization tank 1 through the first steam supply line 2. And the sterilization process which continues the state which filled the vapor | steam in the sterilization tank 1 for a predetermined time is performed. The transition from the steaming process to the sterilization process is executed by detecting the sterilization temperature set by the temperature sensor 22, for example, 135 ° C. Then, after counting the sterilization time is started and the sterilization process for a predetermined time is performed, the sterilization process is finished.

In the steaming process and the sterilization process, the supply of steam into the sterilization tank 1 and the steam jacket 2 is performed based on detection signals from the first and second pressure sensors 20 , 21 . This is done by controlling 11.

  When the sterilization process is completed, an exhaust process is performed in which the second exhaust valve 19 is opened to bring the inside of the sterilization tank 1 to atmospheric pressure. A drying process is performed after this exhaust process. This drying process is performed for a predetermined drying time by opening the first exhaust valve 16 and continuously operating the vacuum pump 17.

  The pressure change in the sterilization tank 1 between the air exclusion process and the drying process is schematically shown in FIG.

  Next, functions and effects of the water absorbing member 6 will be described. During the sterilization process, the saturated vapor passes through the surrounding member 7 and sterilizes the article to be sterilized 4 in the sterilization container 3 by heating. During this sterilization, condensed water of saturated steam adheres to the surface of the article to be sterilized 4, and the adhering condensed water falls and is absorbed and diffused by the water absorbing member 6. It is considered that this condensed water is effectively absorbed by forming the water absorbing member 4 with water-swellable fibers.

  Next, the condensed water absorbed by the water absorbing member 6 during the sterilization process evaporates due to heat transfer from the sterilized object 4 and heat transfer from the sterilization container 3 during the drying process. In particular, since the contact area between the water-absorbing member 6 and the sterilization container 3 is large, heat transfer from the sterilization container 3 becomes dominant in the evaporation.

  The heat transfer from the article to be sterilized 4 includes heat conduction and radiation in which heat directly moves. When the condensed water evaporates in the vicinity of the article to be sterilized 4, the condensed water moves from a part away from the article to be sterilized 4. In the condensed water evaporating action, the radiant heat from the steam jacket 2 is blocked by the surrounding member 7 and therefore hardly contributes to evaporation.

Here, it illustrated by a comparative experiment with comparative example effects due to the use of the water absorbing member 6 of Example 1.

(Contrast experiment 1 using a water absorbent member as a towel)
A non-woven fabric was used as the water-absorbing member 6 of Example 1, and a towel was used as a proportional water-absorbing member, and a drying performance comparison experiment 1 was performed as follows.

  The test object is a stainless steel bat (W600mm x D300mm x H60mm, weight 1348 to 1488g) with a cloth (cotton towel and sheet), and a stainless steel bar (lkg, φ30mm length) as a virtual object to be sterilized 4 above it. 6 (total weight: 160kg) are placed. Thereafter, a non-woven fabric KC500 (W90mm × D900mm) manufactured by Kimberly Clark was double-wrapped and taped with a sterilized tape.

The sheet as the water absorbent member 6 is SA-821 manufactured by Hogi Medical Co., Ltd., and has a surface area (width): W260 mm × D560 mm, and weight: about 18 g. The width (surface area) of the water absorbent member 6 was 100% of the width of the inner bottom surface 5 of the sterilization container 3.
The towel is a cotton towel, surface area: W500mm × D1000mm, weight: about 150g.

The test object was accommodated in the high pressure steam sterilizer, and the sterilization process and the drying process were performed on the following conditions.
Sterilization process setting: High temperature sterilization (sterilization temperature: 135 ° C, sterilization time: 5 minutes)
Drying process: continuous vacuum drying (drying time: 20 minutes)

  The result of the comparison experiment 1 is as shown in FIG. In FIG. 6, the weight increase amount means the weight of the condensed water remaining in the water absorbing member after the drying process. In this comparison experiment 1, it is considered that about 130 g of condensed water is generated during the sterilization process and is absorbed by the water absorbing member 6. When the drying process was completed, 12 g of the water-absorbing member 6 of Example 1 remained in the condensed water absorbed, and 39 g of water remained in the comparative towel.

  The result of the comparative experiment 1 shows that when the water absorbing member 6 of Example 1 is used, the drying performance is remarkably improved as compared with the case where a towel is used. This is because the water-absorbing member 6 is made of a non-woven fabric, so that the air layer in the water-absorbing member 6 can be made thinner as compared with towels made by knitting or weaving fibers. As a result, it is considered that the heat transfer efficiency from the sterilization container 3 and the article to be sterilized 4 to the water absorbing member is higher than that of the towel, and the drying performance is improved.

(Contrast experiment 2 when the number of superposed water-absorbing members is changed)
Next, a comparative experiment 2 for confirming a change in the drying performance when the number of the water-absorbing members 6 was changed was performed as follows.

A stainless steel vat (W60 0m m × D30 0m m × H6 0m m, weight 1348～1488G) as a sterile container 3 laid sheet (W300mm × D200mm, weight 2 to 3 g) as a water absorbing member 6, the center 44g of Water was added dropwise to absorb water. Thereafter, it wrapped double with Kimberly-Clark Corp. The nonwoven fabric K C500 (W900 × D900) as enclosing member 7, was used as an experimental subject those taping with sterile tape.

  The sheet as the water-absorbing member 6 is a non-woven fabric (JP3547 manufactured by Kuraray Laflex Co., Ltd.). The width (surface area) of the water absorbent member 6 was 100% of the width of the inner bottom surface 5 of the sterilization container 3. Then, the number of independent sheets (the number of stacked sheets) was changed, but the amount of dripped water was fixed to 44 g, and the water absorbing member 6 was allowed to absorb water.

The test object was housed in a high-pressure steam sterilizer, and a sterilization process and a drying process were performed under the following conditions, and weight measurements before and after the start were performed.
Sterilization process: High temperature sterilization (sterilization temperature: 135 ° C, sterilization time: 5 minutes)
Drying process: continuous vacuum drying (drying time: 15 minutes)
In addition, condensed water is generated in the sterilization container 3 by the sterilization process, but it is slight.

  The result of the comparison experiment 2 is as shown in FIG. In FIG. 7, the number of overlaps (number of sheets): 1 to 3 shows the results of two experiments under the same conditions, and the number of overlaps: 4 and 5 shows the results of one experiment. FIG. 7 shows that the amount of weight increase, which is the amount of increase from the weight before water absorption, increases as the number of water-absorbing members 6 stacked is increased.

  The result of the comparative experiment 2 shows that the evaporation amount decreases and the drying performance decreases as the number of the water-absorbing members 6 stacked increases. The reason for this is that the distance from the sterilization container 3 to the upper water-absorbing member 6 becomes longer, it is difficult for heat to be transferred from the sterilization container 3 to the upper water-absorbing member 6, and the upper water-absorbing member 6 and the lower water-absorbing member 6 It is considered that a thin air layer is formed between the conductive member 6 and the air layer becomes an obstacle to heat transfer.

DESCRIPTION OF SYMBOLS 1 Sterilization tank 3 Sterilization container 4 Object to be sterilized 5 Inner bottom surface 6 Water absorbing member

Claims (4)

A steam sterilization apparatus that performs a sterilization process in which a material to be sterilized in a sterilization container is housed in a sterilization tank and sterilized with saturated steam, and a drying process for drying the material to be sterilized after the sterilization process,
A water-absorbing member made of water-absorbing paper or nonwoven fabric is laid on the inner bottom surface of the sterilization container, and the sterilization step and the drying step are performed in a state where the sterilized object is set on the water-absorbing member. Steam sterilizer . The steam sterilization apparatus according to claim 1, wherein the paper or the nonwoven fabric is composed of a superabsorbent fiber. The steam sterilization apparatus according to claim 1 or 2, wherein the paper or the nonwoven fabric is disposed on the entire inner bottom surface of the sterilization container. The said paper or nonwoven fabric is single, The steam sterilizer of any one of Claims 1-3 characterized by the above-mentioned.

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