JP6297643B2 - Formaldehyde sterilization indicator and method of using the same - Google Patents

Description

  The present invention relates to a formaldehyde sterilization indicator suitable for indicating completion of formaldehyde sterilization used for sterilizing an object to be sterilized such as a medical device, and a method of using the same.

  As a sterilization process for an object to be sterilized such as a medical device, a sterilization process in which the object to be sterilized is brought into contact with formaldehyde is employed. As this sterilization treatment, formaldehyde gas sterilization treatment in which formaldehyde gas is brought into contact with formaldehyde gas under low humidity, and low temperature steam formaldehyde sterilization treatment (former in low temperature steam formaldehyde; LTSF in which sterilization material is brought into contact with formaldehyde-containing water vapor under high humidity. Sterilization treatment).

  The formaldehyde gas sterilization treatment is performed using a sterilizer having a sterilization chamber and a heating device. Specifically, it is a method of performing sterilization by introducing a low-humidity formaldehyde gas generated by injecting an aqueous formaldehyde solution into a warming device and heating the formaldehyde gas into a sterilization chamber containing an object to be sterilized. According to this sterilization method, the article to be sterilized is sterilized by direct contact with formaldehyde gas under normal temperature conditions of 25 to 30 ° C., humidity of about 50 to 60% RH, and normal pressure.

  The LTSF sterilization process is performed using a sterilizer having a sterilization chamber, a heating device, and a vacuum pump for decompressing the sterilization chamber. First, an aqueous formaldehyde solution is boiled at 55-80 ° C. with a heating device under reduced pressure or under vacuum conditions. The resulting high-humidity low-temperature formaldehyde-containing steam in the same temperature range sucks and fills the sterilization chamber containing the material to be sterilized and kept under reduced pressure or vacuum, and the sterilization chamber is 80% RH or more, specifically In this method, sterilization is performed under high humidity conditions of 95 to 100% RH. According to this sterilization method, an object to be sterilized is sterilized by contact with water vapor containing formaldehyde.

  In these sterilization processes, when the sterilization process is completed, the object to be sterilized comes into contact with formaldehyde evenly and is contacted with formaldehyde at a predetermined concentration for a predetermined time so that workers can recognize that it has been completely sterilized. A formaldehyde sterilization indicator is used having an ink layer that irreversibly discolors to indicate the completion of sterilization.

  As an ink for forming this ink layer, for example, Patent Document 1 discloses an ink composition for formaldehyde gas sterilization treatment containing disodium cromotropate. Chromotrope disodium immediately reacts with formaldehyde-containing water vapor at a temperature higher than room temperature, and changes color very rapidly due to the high temperature and high water vapor. For this reason, when used for LTSF sterilization performed at a temperature higher than that of formaldehyde gas sterilization, the color is changed immediately after the start of sterilization, even before sterilization is completed, and the sterilization of the article to be sterilized is insufficient. However, it will be judged complete.

  On the other hand, Patent Literature 2 discloses a chemical indicator ink for LTSF sterilization treatment containing an organic dye such as Congo Red. Organic dyes having a diazo aromatic ring such as Congo Red combine with formaldehyde molecules in the medium to cause a π-π transition and change color, and thus an aqueous medium such as water vapor is required for the color change. For this reason, when used for sterilization of formaldehyde gas, which is directly sterilized with formaldehyde gas under relatively low humidity conditions and the moisture is unlikely to be involved in the combination of formaldehyde gas and organic dye, it is difficult to change the color to a predetermined color tone. Even if the sterilization process has been completed, it is determined to be incomplete. As a result, the sterilization time is unnecessarily prolonged, so this chemical indicator ink cannot be used for formaldehyde gas sterilization.

  In addition, even if this chemical indicator ink changes color to the specified color tone upon contact with formaldehyde gas, it is caused by the pH change in the sterilization chamber caused by the introduction of ammonia that neutralizes formaldehyde after completion of formaldehyde gas sterilization into the sterilization chamber. As a result, the chemical indicator ink returns to the color tone before the color change.

  Thus, these ink compositions can be used only for either formaldehyde gas sterilization treatment or LTSF sterilization treatment. For this reason, in addition to the complicated operation of using dedicated formaldehyde sterilization indicators for each sterilization treatment, multiple types of formaldehyde sterilization indicators must be purchased, stored, and managed, making handling complicated. It is. This causes an operator who handles the formaldehyde sterilization indicator to make a mistake in selecting the formaldehyde sterilization indicator and to mistake the completion of sterilization.

  Patent Document 3 discloses a formaldehyde sterilization indicator composition having a hydrazine compound, a pyrimidine compound, an organic acid, and an amino compound as discoloring components. This indicator composition for formaldehyde sterilization can be used for both formaldehyde gas sterilization treatment and LTSF sterilization treatment. However, this formaldehyde sterilization indicator is liable to cause side reactions such as air oxidation and decomposition of hydrazine compounds even in the absence of formaldehyde during storage. Therefore, in order to avoid it, the temperature must be lowered, and the product must be stored and transported after being refrigerated / frozen, and handling is complicated. In addition, since a plurality of kinds of substances are used as the color changing component, the raw material management, the manufacturing process is complicated, and the cost is increased.

JP-A-9-26420 JP 2003-222620 A JP-A-7-55796

  The present invention has been made to solve the above-mentioned problems, and in any sterilization treatment of formaldehyde gas sterilization treatment or LTSF sterilization treatment, discoloration can accurately detect and display the completion of sterilization. It is an object of the present invention to provide a formaldehyde sterilization indicator that does not require transportation, can be manufactured easily and inexpensively with high yield, and a method for using the same.

  The formaldehyde sterilization indicator of the present invention made to achieve the above object includes a discoloration component composed of naphthol sulfonic acids containing an intramolecular non-hydrogen-bonded naphthol hydroxyl group, and includes either formaldehyde gas or formaldehyde-containing water vapor. Discoloration is also caused by contact to indicate the completion of sterilization.

（化学式（１）中、Ｘは水素原子、水酸基、又はアミノ基であり、Ｙは水素原子、アミノ基又はＳＯ_３Ｍであり、Ｍは水素原子又はアルカリ金属である）で表わされるα−ナフトールスルホン酸類及び／又は下記化学式（２）

（化学式（２）中、Ｘ、Ｙ、及びＭは前記化学式（１）に同じ）で表されるβ−ナフトールスルホン酸類であってもよい。 In the formaldehyde sterilization indicator, the naphthol sulfonic acids are represented by the following chemical formula (1):

(In the chemical formula (1), X is a hydrogen atom, a hydroxyl group, or an amino group, Y is a hydrogen atom, an amino group, or SO ₃ M, and M is a hydrogen atom or an alkali metal). Sulfonic acids and / or the following chemical formula (2)

(In the chemical formula (2), X, Y and M may be the same as those in the chemical formula (1)).

  As for formaldehyde sterilization indicators, the naphtholsulfonic acids are 1-naphthol-3-sulfonic acid, 1-naphthol-3,6-disulfonic acid, 4,6-dihydroxynaphthalene-2-sulfonic acid, 3,6-dihydroxynaphthalene- 2,7-disulfonic acid, 3-hydroxy-2,7-naphthalenedisulfonic acid, 6-amino-1-naphthol-3-sulfonic acid, 6-amino-4-hydroxy-2-naphthalenesulfonic acid, salts thereof, It is preferably at least one selected from these hydrates and hydrates of these salts.

  In the formaldehyde sterilization indicator, the discoloration component may be contained in the ink layer attached to the base sheet.

  The formaldehyde sterilization indicator includes the discoloration component in the ink layer and a vehicle in which the discoloration component is dispersed, dissolved, and / or mixed, and the content of the discoloration component in the ink layer is 0.1 to 0.1%. It is preferable to set it as 40 mass%.

  The formaldehyde sterilization indicator is a packaging bag containing a sterilized article having a joint portion where the base sheet that transmits the formaldehyde gas and the water vapor containing formaldehyde and the flexible sheet facing the form sheet are joined at the periphery, The ink layer may be sandwiched between both sheets and attached to the joining site.

  The formaldehyde sterilization indicator is formed by sandwiching the ink layer between the base sheet that transmits the formaldehyde gas and the water vapor containing formaldehyde and a flexible or non-flexible covering sheet that is joined to the base sheet. A sterilization display card is preferred.

  The method of using the formaldehyde sterilization indicator of the present invention is such that any one of the above formaldehyde sterilization indicators is subjected to formaldehyde gas sterilization treatment or low-temperature steam formaldehyde sterilization treatment together with an object to be sterilized, and the discoloration component is discolored with formaldehyde, Indication of degree and / or completion.

  According to the formaldehyde sterilization indicator of the present invention, since the naphthol sulfones that are discoloration components are naphthol sulfonic acids that are non-azo and contain an intramolecular non-hydrogen bonding naphthol hydroxyl group, an object to be sterilized and formaldehyde gas at room temperature. It can be used for both the formaldehyde gas sterilization process that comes into contact and the LTSF sterilization process in which the object to be sterilized and the formaldehyde-containing water vapor come into contact at a temperature higher than normal temperature, and irreversibly has a predetermined color tone in these sterilization processes. It is highly reliable because it indicates the complete sterilization accurately and reliably.

  The formaldehyde sterilization indicator can be manufactured quickly and simply at low cost because the discoloration component consists of only naphthol sulfonic acids.

  In addition, the formaldehyde sterilization indicator does not change color or change in quality at normal temperature and humidity, and can be transported and stored at normal temperature and humidity, is easy to handle, and can reduce the burden on the operator. The formaldehyde sterilization indicator has a long shelf life due to the stability of the discoloration component and can be stored for a long time before use, while it does not fade for a long time after use and can be stored as evidence of sterilization history. it can.

  The formaldehyde sterilization indicator is a joint part of the packaging bag adhered to the periphery of the base sheet and the flexible sheet, and the sheet containing the discoloration component-containing ink layer is sandwiched between the two sheets. Indicate the degree and / or completion of sterilization without damaging the ink layer because the ink layer does not rub against other packaging bags and without contaminating the sterilized material because the ink layer does not contact the sterilized material. Can do. If the formaldehyde sterilization indicator is a sterilization display card with a discoloration component-containing ink layer sandwiched between the base sheet and the cover sheet, multiple formaldehyde sterilization indicators can be installed anywhere in the sterilization room, regardless of the packaging shape. Thus, the degree and / or completion of sterilization can be indicated without contaminating the article to be sterilized or the packaging material.

  According to the method of using the formaldehyde sterilization indicator of the present invention, it is not necessary to use a plurality of types of formaldehyde sterilization indicators in either the formaldehyde gas sterilization process or the LTSF sterilization process. Do not make selection mistakes.

It is a perspective view which shows an example of the packaging bag which is a formaldehyde sterilization indicator of this invention. It is an AA line schematic cross-sectional view of the formaldehyde sterilization indicator shown in FIG. It is the top view before and after a formaldehyde sterilization process of the sterilization display card | curd which is a formaldehyde sterilization indicator of this invention, and the BB line schematic cross-sectional view of a formaldehyde sterilization indicator.

  Hereinafter, although the form for implementing this invention is demonstrated in detail, the scope of the present invention is not limited to these forms.

  The perspective view of the packaging bag which is an example of the formaldehyde sterilization indicator of this invention is shown in FIG. The formaldehyde sterilization indicator 10 shown in the figure is a substantially rectangular sterilization bag having a base sheet 14 and a resin-made transparent flexible sheet 15. This sterilization bag accommodates an object to be sterilized (not shown) such as a medical instrument.

  The base sheet 14 is a sterilized paper that is permeable to formaldehyde gas and water vapor containing formaldehyde and impermeable to bacteria. The flexible sheet 15 is formaldehyde gas, formaldehyde-containing water vapor, and a bacteria-impermeable transparent resin film. The base sheet 14 and the flexible sheet 15 are heat-sealed and joined at the three sides of the side edge portion 12a and the lower edge portion 12b which are peripheral portions. Thereby, both the sheets 14 and 15 have the junction site | part 12 mutually affixed by the side edge part 12a and the lower edge part 12b. One side that is not heat-sealed is the opening 13. Since the flexible sheet 15 is transparent, an object to be sterilized accommodated in the formaldehyde sterilization indicator 10 which is a sterilization bag is visually recognized through this.

  A first ink layer 11 a is attached to the central portion of the outer surface of the base sheet 14. The second ink layer 11b is sandwiched between the base sheet 14 and the flexible sheet 15 at the side edge 12a. The first ink layer 11a has a ring shape, and the second ink layer 11b has a substantially rectangular shape. These ink layers 11 are formed of formaldehyde sterilization indicator ink, and the ink layer 11 contains a color-changing component that changes color upon contact with either formaldehyde gas or formaldehyde-containing water vapor. The ink for formaldehyde sterilization indicator may be prepared containing various additives such as a vehicle and a non-discoloring component together with the discoloring component. The ink layer may be only one of the first ink layer 11a and the second ink layer 11b.

（化学式（１）中、Ｘは水素原子、水酸基、又はアミノ基であり、Ｙは水素原子、アミノ基、又はＳＯ_３Ｍであり、Ｍは水素原子、又はＬｉ、Ｎａ及びＫのようなアルカリ金属である）や、下記化学式（２）

（化学式（２）中、Ｘ、Ｙ、及びＭは化学式（１）に同じ）で表すことができるものである。 This discoloration component is composed of naphthol sulfonic acids containing an intramolecular non-hydrogen bonding naphthol hydroxyl group. The intramolecular non-hydrogen bonding naphthol hydroxyl group means a hydroxyl group that does not form a hydrogen bond with another hydroxyl group bonded to the same naphthalene ring. Naphthol sulfonic acids having an intramolecular non-hydrogen-bonded naphthol hydroxyl group are exemplified by the following chemical formula (1)

(In the chemical formula (1), X is a hydrogen atom, a hydroxyl group, or an amino group, Y is a hydrogen atom, an amino group, or SO ₃ M, and M is a hydrogen atom or an alkali such as Li, Na, and K. Metal) and the following chemical formula (2)

(In the chemical formula (2), X, Y, and M are the same as those in the chemical formula (1)).

  Specific examples of the α-naphtholsulfonic acids represented by the chemical formula (1) and the β-naphtholsulfonic acids represented by the chemical formula (2) include 1-naphthol-3-sulfonic acid and 1-naphthol-3,6. -Disulfonic acid, 4,6-dihydroxynaphthalene-2-sulfonic acid, 3,6-dihydroxynaphthalene-2,7-disulfonic acid, 3-hydroxy-2,7-naphthalenedisulfonic acid, 6-amino-1-naphthol- Specific examples include non-azo specific naphthol sulfonic acids or dihydroxynaphthalene sulfonic acids composed of at least one selected from 3-sulfonic acid and 6-amino-4-hydroxy-2-naphthalene sulfonic acid. These naphthol sulfonic acids may be a salt, a hydrate, or a hydrate of a salt.

  For example, the discoloration component that is 1-naphthol-3,6-disulfonic acid disodium hydrate exhibits a white color in a state that it is not in contact with formaldehyde gas and formaldehyde-containing water vapor. Formaldehyde gas sterilization performed under conditions of atmospheric pressure, room temperature, and humidity of 50-60% RH with formaldehyde gas generated from a heated aqueous formaldehyde solution gives light orange color, and is an original white color Do not return to. In addition, 1-naphthol-3,6-disulfonic acid disodium hydrate as a discoloring component is subjected to LTSF sterilization performed under reduced pressure or vacuum, at a temperature of 55 to 80 ° C., and a humidity of 80% RH or more. When applied, it exhibits a deep orange color and does not return to its original white color.

  The discoloration component contained in the ink layer 11 is brought into contact with formaldehyde, for example, by condensation, cocondensation, polycondensation, or dimethylolation, thereby changing the delocalization state of π electrons, and irreversibly as described above. It is considered to change color. Further, the discoloration component exhibits a light color tone in a formaldehyde gas sterilization treatment performed at a relatively low humidity and normal temperature, and a dark color tone in an LTSF sterilization treatment performed at a high humidity and a temperature higher than normal temperature. This shading is presumed to depend on humidity and temperature.

  Thus, since the ink layer 11 containing the color-changing component that reacts by contact with any of formaldehyde gas and formaldehyde-containing water vapor, irreversibly discolors and does not fade after sterilization treatment is attached, the formaldehyde of the present invention The sterilization indicator 10 can accurately and reliably indicate that the sterilization process has been performed properly and sufficiently, and can store a record thereof. In addition, the formaldehyde sterilization indicator 10 alone can be used for both formaldehyde gas sterilization treatment and LTSF sterilization treatment, and it can indicate which one has been implemented by the shade of the color to be exhibited. Therefore, the formaldehyde sterilization indicator 10 can be easily managed, and it is not necessary to properly use a plurality of indicators according to each sterilization process. Does not cause.

  Further, this discoloration component does not oxidize or absorb moisture due to oxygen or moisture in the air at room temperature, does not deteriorate by light or heat, and does not discolor or change quality. Therefore, the formaldehyde sterilization indicator 10 does not require refrigerated transportation or refrigerated storage, can be transported or stored at room temperature, and can be stocked for a long time without deterioration, so that it can be handled easily. In addition, the ink layer 11 contains only at least one of the naphthol sulfonic acids described above as a discoloring component, and can be discolored in both formaldehyde gas sterilization treatment and LTSF sterilization treatment to indicate completion of sterilization treatment. The formaldehyde sterilization indicator 10 can simplify the management and manufacturing process of the raw material of the discoloration component, and can be manufactured at an extremely low cost.

  The ink layer 11 includes a vehicle, and when the discoloration component is dispersed, dissolved, and / or mixed in the vehicle, the prepared ink for formaldehyde sterilization indicator is printed on the base sheet 14. Only the ink layer 11 can be formed.

  As the vehicle contained in the ink for formaldehyde sterilization indicator, non-color-changeable materials such as acrylic resin, phenol resin, nylon, ethylcellulose, hydroxymethylcellulose, polyvinyl alcohol, and carboxymethylcellulose can be mentioned without disturbing the discoloration of the discoloration component. It may be a commercially available ink vehicle, PAS800 medium (trade name, manufactured by Jujo Chemical Co., Ltd.) or high-set mat medium (trade name, manufactured by Mino Group, Inc.). Dicure AK (trade name, manufactured by DIC Corporation), FDS New (trade name, manufactured by Toyo Ink Co., Ltd.), Reicure TU4400 (trade name, manufactured by Jujo Chemical Co., Ltd.), UVSPA Clear (trade name, manufactured by Teikoku Ink Manufacturing Co., Ltd.) ), UV8418 (trade name, manufactured by Seiko Advance Co., Ltd.).

  The ink for formaldehyde sterilization indicator may contain a solvent that dissolves the vehicle. Such solvents include, for example, water, ethanol, butanol, ethyl acetate, isoamyl acetate, methyl ethyl ketone, methyl isobutyl ketone, xylene, diethylbenzene, toluene, butyl cellosolve, ethyl cellosolve, mineral spirit, and UV curable resin. The monomer of the photosensitive resin is mentioned. The solvent is appropriately selected according to the type of vehicle and the printing method.

  The formaldehyde sterilization indicator ink may contain a dispersant such as talc, magnesium carbonate, and silica that disperses the discoloration component so that the color change of the discoloration component becomes clear. Furthermore, additives such as anti-settling agents, thickeners, and surfactants that improve printability may be included.

  If necessary, in the ink for formaldehyde sterilization indicator, in addition to the color-changing component, as color formers, for example, ammonium salts such as ammonium salicylate and ammonium sulfate, amines such as ethylamine hydrochloride and aminophenol, benzenesulfonamide and nicotinic acid Amides such as amides, nitrogen compounds having a cyclic structure such as 1,2,4-triazole and 2-mercaptobenzothiazole, and organic sulfur compounds other than discoloring components such as dipentamethylene thiuram tetrasulfide, 2,2 Thiourea compounds such as' -dibenzothiazolyl disulfide, L-cystine, and 2,2'-ditolylthiourea may be included.

  The content rate of the color changing component with respect to the ink layer 11 formed with such an ink for formaldehyde sterilization indicator is preferably 0.1 to 40% by mass, and more preferably 0.1 to 30% by mass. When the content rate of the discoloration component is within these ranges, the formaldehyde sterilization indicator 10 is excellent in printability, and the formed formaldehyde sterilization indicator 10 exhibits a clear and seemingly distinguishable color change. . On the other hand, if it is less than 0.1% by mass, the change in color tone before and after the color change is not noticeable, and if it exceeds 40% by mass, the ink layer 11 cannot be formed.

FIG. 2 shows a schematic cross-sectional view of the formaldehyde sterilization indicator 10 taken along the line AA. The sterilized paper used for the base sheet 14 is a nonwoven sheet such as pulp, flash-spun polyethylene nonwoven fabric, or a mixed paper thereof, and preferably has a basis weight of 40 to 80 g / m ² . The base sheet 14 may be a material that transmits formaldehyde gas and water vapor containing formaldehyde and does not transmit bacteria, and may be a porous resin film having these characteristics.

  The flexible sheet 15 is one in which an outer film 15a, a laminate layer 15b, and an inner film 15c are bonded and integrated in this order. The outer film 15a is a transparent biaxially stretched polyethylene terephthalate (PET) film having a thickness of 5 to 20 μm, preferably 8 to 15 μm. The inner film 15c is a transparent unstretched polypropylene (PP) film or low density polyethylene (LDPE) film having a thickness of 15 to 100 μm, preferably 20 to 40 μm.

  The laminate layer 15b is interposed between the outer film 15a and the inner film 15c. For example, a transparent adhesive layer in which a polyester polyol-isocyanate two-component adhesive is applied to the outer film 15a or the inner film 15c. It is.

  The formaldehyde sterilization indicator 10 is manufactured as follows.

  First, an ink for formaldehyde sterilization indicator is prepared by putting the color-changing component and the vehicle into a dispersing machine such as a ball mill, a roll mill, a sand mill, and / or a likai machine and mixing them. The discoloration component is preferably dissolved in the vehicle. According to this, since the formaldehyde sterilization indicator 10 is subjected to the formaldehyde gas sterilization treatment and the LTSF sterilization treatment, the entire ink layers 11a and 11b are made uniform, so that the color difference before and after the discoloration of the ink layers 11a and 11b is conspicuous. Visibility can be improved. The discoloration component may be dispersed in the vehicle. According to this, since the discoloration component dispersed in the vehicle is covered with this, the particle surface of the discoloration component is surely protected or smooth and prevents irregular reflection of light. 10 shows the stability which was further excellent in transportation and storage under normal temperature conditions, or shows a clear color and becomes easy to visually recognize. The vehicle is preferably permeable to formaldehyde gas and formaldehyde gas-containing vapor. Moreover, after mixing a vehicle and a color-change component, you may provide the viscosity suitable for various printing to the ink for formaldehyde sterilization indicators by adding a solvent.

  Next, the ink for formaldehyde sterilization indicator is applied by printing to the central part on one outward side of the sterilized paper that is the material of the base sheet 14 and the two opposite sides on the other inward side. Thus, the solvent is volatilized to form the ring-shaped first ink layer 11a and the rectangular second ink layer 11b.

  An adhesive is applied to one surface of the outer film 15a to form a laminate layer 15b, and the inner film 15c is bonded thereto by a dry lamination method to produce the flexible sheet 15.

  The second ink layer 11b and the inner film 15c face each other, the base sheet 14 and the flexible sheet 15 are stacked, and these are heat-sealed by heat-sealing the three sides of the peripheral portion. As a result, a lower edge portion 12b where the sheets 15 and 16 are joined together and a joining portion 12 which is a side edge portion 12a joined while sandwiching the second ink layer 11b is formed, and the sterilized bag-like formaldehyde sterilization indicator 10 is formed. Get.

  A method of using the formaldehyde sterilization indicator 10 will be described with reference to FIGS.

  The formaldehyde sterilization indicator 10 is transported and stored under normal temperature conditions without being refrigerated. An object to be sterilized, which is a medical instrument such as a scissors, a scalpel, and tweezers, is accommodated by the operator in the formaldehyde sterilization indicator 10 from the opening 13, and close to the lower edge 12 b of the opening 13, and the base sheet 14 is acceptable. The flexible sheet 15 is thermally welded by a heat sealer. Thereafter, the article to be sterilized, which is transported and stored under normal temperature conditions as needed and still contained in the formaldehyde sterilization indicator 10, is subjected to formaldehyde sterilization treatment.

  First, the case where formaldehyde gas sterilization is performed will be described. A formaldehyde sterilization indicator 10 containing an object to be sterilized is placed on a shelf (not shown) in the sterilization chamber of the sterilizer. After the sterilizer door is closed and the sterilization chamber is sealed, a 12 mass% formaldehyde aqueous solution is injected into the heating device of the sterilizer, and formaldehyde gas generated by the heating is introduced into the sterilization chamber. Formaldehyde gas causes a temperature drop in the introduction path connecting the heating device and the sterilization chamber. As a result, a room-temperature sterilization chamber has a 2000 ppm formaldehyde atmosphere. In addition, when heating the aqueous formaldehyde solution, the inside of the heating device may be decompressed to 20 to 90 kPa. At this time, the sterilization chamber is preferably pressurized to at least 90 kPa.

  This atmosphere is maintained for 180 minutes. Thereby, the sterilization treatment is performed on the article to be sterilized, and the discoloration component contained in the ink layer 11 of the formaldehyde sterilization indicator 10 is, for example, in the absence of a solvent such as a water solvent or an organic solvent, The color changes from white to pale orange. As a result, the formaldehyde sterilization indicator 10 becomes visible as the discoloration of the ink layer 11 and can detect that the formaldehyde gas sterilization is completed.

  Thereafter, residual formaldehyde gas in the sterilization chamber is removed. The door of the sterilizer is opened by the operator, and the formaldehyde sterilization indicator 10 is taken out together with the article to be sterilized. Since the formaldehyde sterilization indicator 10 has the first ink layer 11a and the second ink layer 11b, the operator slightly tilts the formaldehyde sterilization indicator 10 by hand. Only by visually observing that the formaldehyde sterilization indicator 10 has been changed to a predetermined color tone, it can be quickly confirmed that the sterilization treatment has been reliably performed under appropriate conditions. Thereby, the formaldehyde sterilization indicator 10 reduces the work burden on the operator.

  Next, the case where the LTSF sterilization process is performed will be described. Similar to the formaldehyde gas sterilization process, the formaldehyde sterilization indicator 10 is placed on the shelf of the sterilization chamber. Thereafter, the sealed sterilization chamber is evacuated to 5 to 25 kPa and kept at 55 to 70 ° C. Formaldehyde-containing water vapor generated by ultrasonic boiling of an aqueous formaldehyde solution (formaldehyde concentration of 2 to 38% by mass) is introduced into the sterilization chamber. The sterilization chamber is maintained at a temperature of 55 to 70 ° C. and a humidity of 80% RH or more for 45 minutes. Thereby, the sterilization process is performed on the object to be sterilized, and the discoloration component contained in the ink layer 11 of the formaldehyde sterilization indicator 10 is discolored, for example, from white to dark orange in a formaldehyde gas-containing steam atmosphere. Furthermore, after ammonia is introduced into the sterilization chamber and formaldehyde is neutralized, the operator opens the door of the sterilizer, and the formaldehyde sterilization indicator 10 is taken out together with the object to be sterilized. At this time, since the formaldehyde sterilization indicator 10 does not return to white, the operator can confirm that the LTSF sterilization process has been completed and the sterilization process has been performed by simply looking at the formaldehyde sterilization indicator 10 that has turned dark orange. I can confirm.

  The formaldehyde sterilization indicator 10 may be a sterilization bag shown in FIGS. 1 and 2, a sheet having a base sheet with an ink layer, a container, and a container.

  FIG. 3 shows a plan view of a sterilization display card which is a formaldehyde sterilization indicator 10. FIG. 4A shows the color change component before the color change, and FIG. 4B shows the color change component after the color change. Moreover, in the figure (c), the BB line schematic cross-sectional view of the formaldehyde sterilization indicator 10 is shown. The sterilization display card is a thin card that is rectangular in plan.

  As shown in FIG. 3 (c), the formaldehyde sterilization indicator 10 includes a base sheet 14 that is sterilized paper that transmits formaldehyde gas and formaldehyde-containing water vapor, and a cover sheet made of a thermoplastic resin that overlaps one surface of the base sheet 14. A certain flexible sheet 15 is provided. The flexible sheet 15 is a single transparent polypropylene film. The ink layer 11 containing a color changing component is attached to the base sheet 14 while being surrounded by the printing layer 16, and is sandwiched between this and the flexible sheet 15. Thereby, the ink layer 11 is protected from scratches and water wetting during transportation and storage. The base sheet 14 and the flexible sheet 15 are attached to each other by heat sealing.

  As shown in FIG. 5A, a letter “OK” is drawn at a position near one of the short sides of the formaldehyde sterilization indicator 10. In this state, the discoloration component contained in the ink layer 11 has the same color as that of the base sheet 14 and therefore is not visually recognized through the flexible sheet 15.

  The formaldehyde sterilization indicator 10 which is a sterilization display card is placed in the sterilization chamber together with the article to be sterilized when the article to be sterilized is subjected to formaldehyde gas sterilization treatment or LTSF sterilization treatment after being transported and stored at room temperature. When the formaldehyde sterilization indicator 10 reacts with formaldehyde of formaldehyde gas or formaldehyde-containing water vapor, the discoloration component changes color, and the discoloration component exhibits a color tone different from that of the base sheet 14. As a result, the letters “OK” appear in a visible manner, and the completion of the sterilization process is displayed as a result of the sterilization process being properly and reliably performed on the sterilized object.

  The discoloration component contained in the ink layer 11 changes from a light color to a dark color depending on the formaldehyde concentration and the contact time with which it contacts. For example, a standard color that corresponds to the degree of progress of sterilization and the color of the discolored component is compared with the color tone that the discolored component exhibits by sterilization, and the degree and degree of sterilization are displayed in addition to the completion of formaldehyde sterilization As such, the formaldehyde sterilization indicator 10 may be used. As a chemical indicator, the formaldehyde sterilization indicator 10 shows a result similar to the biological detection result of detecting the suitability of sterilization based on the presence or absence of bacterial growth due to culture.

  Examples of the present invention will be described in detail below, but the scope of the present invention is not limited to these examples.

(Example 1-1)
50 g of acrylic resin as a vehicle and 50 g of butyl cellosolve as a solvent were added and mixed to dissolve the vehicle. To this was added 1 g of sodium 1-naphthol-3-sulfonate as a discoloring component, and the mixture was placed in a ball mill pot and kneaded to prepare an ink for formaldehyde sterilization indicator. This was screen-printed on rectangular sterilized paper as a base sheet to form an ink layer containing a discoloration component. After the ink layer was dried and the solvent was volatilized, a protective sheet made of polypropylene was stacked on the base sheet and the entire surface was heat-sealed with a heat sealer so as to sandwich the ink layer, and this was a sterilization display card. One formaldehyde sterilization indicator was made.

(Examples 1-2 to 1-7)
Except having changed the kind of color-change component as shown in Table 1, the formaldehyde sterilization indicator of Examples 1-2 to 1-7 which is a sterilization display card was produced like Example 1-1.

(Example 2-1)
A formaldehyde sterilization indicator of Example 2-1 which is a sterilization display card was produced in the same manner as Example 1-1 except that the amount of discoloration component was 30 g.

(Examples 2-2 to 2-7)
Except having changed the kind of color-change component as shown in Table 2, the formaldehyde sterilization indicator of Examples 2-2 to 2-7 which is a sterilization display card was produced like Example 2-1.

(Example 3-1)
Example which is a sterilization display card in the same manner as Example 1-1 except that a polyester acrylate UV curable resin is used as a vehicle, ethyl acetate is used as a solvent, and relief printing is used instead of screen printing. A 3-1 formaldehyde sterilization indicator was prepared.

(Examples 3-2 to 3-7)
Except having changed the kind of color-change component as shown in Table 3, the formaldehyde sterilization indicator of Examples 3-2 to 3-7 which is a sterilization display card was produced like Example 3-1.

(Example 4-1)
A formaldehyde sterilization indicator of Example 4-1 as a sterilization display card was produced in the same manner as in Example 3-1, except that the amount of discoloration component was 30 g.

(Examples 4-2 to 4-7)
Except having changed the kind of discoloration component as shown in Table 4, the formaldehyde sterilization indicator of Examples 4-2 to 4-7 which is a sterilization display card was produced like Example 4-1.

(Example 5-1)
To 15 g of urethane resin as a vehicle, 7 g of methyl ethyl ketone (MEK) as a solvent was added and mixed to dissolve the vehicle. To this was added 0.1 g of sodium 1-naphthol-3-sulfonate as a discoloring component, and the mixture was placed in a ball mill pot and kneaded to prepare an ink for formaldehyde sterilization indicator. This was gravure-printed so as to draw a ring shape on one surface of sterilized paper, which is a rectangular base sheet, to give a first ink layer. On the other side of this sterilized paper, gravure printing was performed so as to draw a rectangle, and a second ink layer was applied. An example of a sterilization bag in which sterilized paper and a flexible sheet are overlapped so that the first ink layer is on the outside, and these are heat-sealed on the three sides of the peripheral portion and heat-sealed to form a joining portion. A 4-1 formaldehyde sterilization indicator was prepared.

(Examples 5-2 to 5-7)
Except having changed the kind of discoloration component as shown in Table 5, the formaldehyde sterilization indicator of Examples 5-2 to 5-7 which is a sterilization bag was produced like Example 5-1.

(Examples 6-1 to 6-7)
Formaldehyde sterilization indicators of Examples 6-1 to 6-7, which are sterilization bags, were produced in the same manner as in Examples 5-1 to 5-7, except that the amount of each color changing component was 5 g.

(Comparative Example 1)
In accordance with Patent Literature 3, 30 g of butyl cellosolve as a solvent was added to PAS800 medium (trade name, manufactured by Jujo Chemical Co., Ltd.) as a vehicle and mixed to dissolve the vehicle. To this, 20 g of hydrazine sulfate, 5 g of 4,6-dimethyl-2-hydroxypyrimidine, 5 g of maleic acid, and 5 g of sulfanilic acid were added as a color-changing component, put into a ball mill, kneaded for 72 hours, and formaldehyde sterilization indicator An ink was prepared. Thereafter, the formaldehyde sterilization indicator of Comparative Example 1 was produced in the same manner as in Example 1-1.

(Comparative Example 2)
The ink for formaldehyde sterilization manufactured by Tempil (trade name: Tempilink TIFFRG 492) was flexographically printed on a rectangular sterilized paper to form an ink layer. Thereafter, the same operation as in Example 1 was performed to prepare a formaldehyde sterilization indicator of Comparative Example 2.

(Comparative Example 3)
As a formaldehyde sterilization indicator of Comparative Example 3, a sterilization card (trade name: Self-adhesive package monitoring indicator) manufactured by gke was used.

(Comparative Example 4)
As the formaldehyde sterilization indicator of Comparative Example 4, a chemical indicator attached to the ACE test biological indicator purchased from Fukuzawa Shoji Co., Ltd. (trade name: chemical indicator attached to the ACE test biological indicator (for formalin sterilization)) was used. .

(Comparative Example 5)
A formaldehyde sterilization indicator of Comparative Example 5 was prepared in the same manner as in Example 1-1 except that disodium chromotrope was used as the color changing component.

(Formaldehyde gas sterilization test)
The formaldehyde sterilization indicators of Examples 1-1 to 1-7 and Comparative Examples 1 to 5 were placed side by side so as not to overlap in a formaldehyde gas sterilizer (trade name: Ecopulsar PS-140R, manufactured by Mediate Co., Ltd.). . Thereafter, the sterilization chamber is sealed, and an aqueous formaldehyde solution is injected into the heating device of the sterilizer so that the formaldehyde concentration in the sterilization chamber becomes 2000 ppm and heated to 50 ° C. to vaporize the formaldehyde, and the humidity in the sterilization chamber is 50 Hold for 180 minutes while maintaining ~ 60% RH. Next, after removing the residual formaldehyde gas in the sterilization chamber, all formaldehyde sterilization indicators were taken out and visually checked for discoloration.

(LTSF sterilization test)
The formaldehyde sterilization indicators of Examples 1-1 to 1-7 and Comparative Examples 1 to 5 were placed side by side so as not to overlap each other in the LTSF sterilizer (manufactured by GETINGE, trade name: HS66 TurboLTSF). Thereafter, the sterilization chamber was sealed, formaldehyde-containing water vapor (formaldehyde concentration 2%) was introduced into the sterilization chamber, and maintained for 45 minutes while maintaining the humidity in the sterilization chamber at 80% RH or higher and the temperature at 55 ° C. Next, after removing the residual formaldehyde-containing water vapor in the sterilization chamber, all the formaldehyde sterilization indicators were taken out and visually checked for discoloration.

(Accelerated storage test)
The formaldehyde sterilization indicators of Examples 1-1 to 1-7 and Comparative Examples 1 to 5 were arranged so as not to overlap in a constant temperature and humidity chamber maintained at a temperature of 40 ° C. and a humidity of 80% RH, and left for 6 months. An accelerated storage test was conducted. Thereafter, all formaldehyde sterilization indicators were taken out and visually checked for discoloration.

  Only the formaldehyde sterilization indicator of Comparative Example 1 was subjected to a formaldehyde sterilization treatment test and an LTSF sterilization treatment test.

  Table 7 summarizes the results of the formaldehyde gas sterilization test, the LTSF sterilization test, and the accelerated storage test. In Table 7, with respect to the formaldehyde gas sterilization test and the LTSF sterilization test, ◯ indicates that there is discoloration, × indicates discoloration to a color other than a predetermined color tone or discoloration to a predetermined color tone when sterilization is not completed, and xx Indicates no discoloration. Regarding the accelerated storage test, ○ indicates no abnormal discoloration, and × indicates abnormal discoloration that was discolored without contact with formaldehyde.

  As shown in Table 7, the formaldehyde sterilization indicators of Examples 1-1 to 1-7 to which the present invention is applied can be used for sterilization of both formaldehyde gas sterilization and LTSF sterilization, and can be stored at room temperature. It was a thing. On the other hand, as shown in Comparative Examples 1-5, the conventional formaldehyde sterilization indicator has deteriorated due to the accelerated storage test, so it can be discolored without being exposed to formaldehyde, or the completion of formaldehyde gas sterilization processing cannot be displayed. Since it changed color before completion of the LTSF sterilization treatment, it was lacking in versatility as a formaldehyde sterilization indicator.

  The formaldehyde sterilization indicator of the present invention is used for sterilization of both formaldehyde gas sterilization and LTSF sterilization after being transported and stored at room temperature.

  The method of using the formaldehyde sterilization indicator of the present invention can be applied to any sterilization treatment of formaldehyde gas sterilization treatment and LTSF sterilization treatment after transportation and storage at room temperature.

  10 is an aldehyde sterilization indicator, 11 is an ink layer, 11a is a first ink layer, 11b is a second ink layer, 12 is a bonding site, 12a is a side edge, 12b is a lower edge, 13 is an opening, and 14 is a base A sheet, 15 is a flexible sheet, 15a is an outer film, 15b is a laminate layer, 15c is an inner film, and 16 is a printing layer.

Claims (8)

  A formaldehyde sterilization indicator comprising a discoloration component comprising a naphthol sulfonic acid containing an intramolecular non-hydrogen-bonded naphthol hydroxyl group, and displaying disinfection completion by discoloration upon contact with either formaldehyde gas or formaldehyde-containing water vapor . The naphthol sulfonic acids are represented by the following chemical formula (1)

(In the chemical formula (1), X is a hydrogen atom, a hydroxyl group, or an amino group, Y is a hydrogen atom, an amino group, or SO ₃ M, and M is a hydrogen atom or an alkali metal). Sulfonic acids,
And / or the following chemical formula (2)

(In the chemical formula (2), X, Y, and M are the same as the chemical formula (1)).
The formaldehyde sterilization indicator according to claim 1, wherein the β-naphthol sulfonic acids represented by the formula:   The naphthol sulfonic acids are 1-naphthol-3-sulfonic acid, 1-naphthol-3,6-disulfonic acid, 4,6-dihydroxynaphthalene-2-sulfonic acid, 3,6-dihydroxynaphthalene-2,7-disulfone. Acid, 3-hydroxy-2,7-naphthalenedisulfonic acid, 6-amino-1-naphthol-3-sulfonic acid, 6-amino-4-hydroxy-2-naphthalenesulfonic acid, salts thereof, hydrates thereof And a formaldehyde sterilization indicator according to claim 1, wherein the formaldehyde sterilization indicator is at least one selected from hydrates of these salts.   The formaldehyde sterilization indicator according to any one of claims 1 to 3, wherein the discoloration component is contained in an ink layer attached to a base sheet.   The ink layer contains the color changing component and a vehicle in which the color changing component is dispersed, dissolved, and / or mixed, and the content of the color changing component in the ink layer is 0.1 to 40% by mass. The formaldehyde sterilization indicator according to claim 4.   The base sheet that transmits the formaldehyde gas and the formaldehyde-containing water vapor and the flexible sheet facing the base sheet have a bonding part bonded at the periphery, and is a packaging bag that contains an object to be sterilized. The formaldehyde sterilization indicator according to claim 4, wherein the formaldehyde sterilization indicator is sandwiched between sheets and attached to the joining portion.   A sterilization display card in which the ink layer is sandwiched between the base sheet that transmits the formaldehyde gas and the water vapor containing formaldehyde and a flexible or non-flexible covering sheet that is joined to the base sheet. The formaldehyde sterilization indicator according to claim 4, wherein the formaldehyde sterilization indicator is provided.   The formaldehyde sterilization indicator according to any one of claims 1 to 7 is subjected to formaldehyde gas sterilization treatment or low-temperature steam formaldehyde sterilization treatment together with an object to be sterilized, and the discoloration component is discolored with formaldehyde, and thereby the degree of sterilization and / or A method of using a formaldehyde sterilization indicator, characterized by indicating completion.

Images