JPS6038430B2 - Indicator ink for ethylene oxide gas sterilization - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an improvement in a sterilization indicator ink for ethylene oxide gas sterilization, and particularly to an indicator ink that exhibits a clear color change before and after ethylene oxide gas sterilization.

Medical or surgical equipment or surgical gowns used in hospitals,
It goes without saying that all coverings, rubber gloves, gauze, etc. must be sterilized and sterile.

Currently, medical and surgical equipment used in hospitals are generally sterilized by their manufacturers before being delivered to hospitals. Ethylene oxide gas sterilization is often used as a sterilization method in such cases. Furthermore, among these medical and surgical instruments, those that are not disposable but can be used repeatedly are washed and sterilized in a central material room within the hospital after use, and then reused.

High-pressure steam sterilization is often used as a sterilization method in this case, but ethylene oxide gas sterilization is exclusively used for plastic products and rubber products that are sensitive to heat and steam. By the way, when sterilizing medical or surgical equipment with ethylene oxide gas, it is necessary to preserve the sterilized equipment aseptically until use, so each item must be sterilized with paper, cloth, non-woven fabric, or plastic film. The product is packaged in a bag or other packaging material, and sterilized while still in the package.

Here, sterilization indicator ink that changes color before and after ethylene oxide gas sterilization treatment is printed on a conspicuous location on the outside of the package of these medical and surgical instruments to be sterilized, or Alternatively, by attaching adhesive labels, adhesive tapes, etc. on which the indicator ink has been printed in advance, sterilized medical,
It is possible to prevent packaging items such as surgical equipment from being mixed up with unprocessed items. In addition, sterilization indicator ink that changes color when sterilization conditions are met is printed near the center of the package of these medical and surgical instruments to be sterilized. The card is inserted and the sterilization condition inside the package is checked for each package. Conventionally, the indicator ink for ethylene oxide gas sterilization used for applications such as
Known examples include those described in Japanese Patent Publication No. 29 and Japanese Patent Publication No. 52-10043. The former is an indicator ink that contains a basic substance, hydrochloride, and an indicator, taking advantage of the property of ethylene oxide to combine with hydrogen chloride, and although its hue change and color density are good, Since the light resistance of pH indicators is generally poor, they tend to turn brown when stored in the light for a long period of time.

In addition, the latter utilizes the principle that an azo dye with a specific molecular structure containing a thiazole ring changes color when it reacts with ethylene oxide, and the hue change or color of the ink before and after ethylene oxide gas sterilization treatment is observed. Although it has excellent density, it cannot be said that the color clarity is sufficient.

The inventors of the present application have developed an ethylene oxide gas that has excellent preservability for printed matter, large hue changes and color density before and after sterilization using ethylene oxide gas, and excellent color clarity, which is important for identifying color differences. As a result of extensive research into sterilization indicator ink, the present invention was achieved.

That is, the present invention relates to the following general formula {11 [wherein R is a hydrogen atom, a lower alkyl group, a lower alkoxy group, a phenyl group, a benzyl group, a nitro group, a mercapto group, a lower alkylthio group, a benzylthio group, and a lower alkylsulfonyl group] represents.

is a benzene nucleus, and R2 and R3 each represent a hydrogen atom, a nitroso group, a lower alkyl group, a substituted lower alkyl group, a fenyl group, and a penzyl group.

R2 and R3 may be combined to form a ring.
Further, the benzene nucleus may have a non-dissociable direct fusuma group.

] 1,3,4-thiadiazole ring and P-
The present invention relates to an indicator ink for ethylene oxide gas sterilization characterized by using an azo dye containing an aniline or aniline derivative structure coupled at the position as a color-changing colorant. Examples of the straight lower alkyl group represented by R2 or R3 in the above single-pronged formula '1} are 8
-Hydoxyethyl group (1CH2CH20H), B-cyanoethyl group (1C&-CH2CN), 8-methoxyethyl group (1C4CH20C&), 8-phenoxyethyl group, and the like.

R2 and R3 are combined a ring formed by An example of the structure is Piverizine Liao morpholine ring pyrrole ring etc.

Furthermore, examples of non-demagnetizing substituents that the benzene nucleus can take include lower alkyl groups, lower alkoxy groups, acylamino groups, nitro groups, and chlorine atoms.

The dye represented by the above general formula '1} used in the indicator ink for ethylene oxide gas sterilization of the present invention can be synthesized by a known synthesis method.

For example, by diazotizing 2-amino-5-1,3,4-thiadiazole represented by the general formula {31 [in the formula, R has the above-mentioned meaning],
2 and R3 have the above-mentioned meanings].

Although the indicator ink for ethylene oxide gas sterilization of the present application, which is produced using the azo dye represented by the above general formula [1}, can be made into one suitable for any printing method, it is particularly suitable for use as a grabber printing ink or It is easy to make an ink suitable for flexo printing.

That is, an azo dye represented by the general formula '1' is dissolved in a solvent mainly composed of an alcohol solvent, an ester solvent, a ketone solvent, an aromatic hydrocarbon solvent, or an aliphatic hydrocarbon solvent, and then It can be manufactured by adding a polymeric substance soluble in these solvents as a binder. However, in this case it is generally necessary to add acidic substances to accelerate the reaction between the dye and ethylene oxide.

Effective acidic substances include inorganic solid acids such as silica, acid clay, and activated clay, malonic acid, maleic acid, citric acid,
0 nitrobenzoic acid, salicylic acid, 2-hydroxy-3
- naphthoic acid, phthalic acid, phthalic anhydride, one or more hydrophobic substituents (tert-butyl group, benzyl group, etc.)
(e.g., P-tert-butylbenzoic acid, 3-tert-butylsalicylic acid, etc.), many organic acids such as bisphenol A, and polyvalent metal salts of such organic acids (Ca, Mg , N, Zn,
Mn, Cu, Co salts, etc.) can be used, but in order to prevent the acidic substances in the ink from transferring to the printing substrate, such as paper, if the printed matter of the indicator ink is stored in a high-temperature environment, it must be slightly water-repellent. , it is preferable to use one. Further, if a polymeric substance having an acidic group in its molecule is used as a binder to be added to the above-mentioned indicator ink, the amount of addition of the above-mentioned acidic substance may be reduced. Examples of binders having such acidic groups include styrene-maleic anhydride copolymers, vinyl chloride-vinyl acetate-maleic anhydride copolymers, and hydrolysates thereof, vinyl chloride-vinyl acetate-acrylic acid copolymers. Examples include coalescence, rosin-modified maleic acid resin, and phenolaldehyde resin. The above-mentioned additives of acidic substances vary depending on the acid strength of the acid added, the properties and amount of the binder used in the ink, so it cannot be generalized, but in most cases the color-changing colorant used in the ink An amount of 1'a to 1p of the azo dye is used. In addition to the above-mentioned additives, the indicator ink for ethylene oxide gas sterilization of the present invention contains colorless and colored pigments, other dyes that do not change color due to ethylene oxide, and various other materials commonly added to printing inks. Additives can also be added. Furthermore, two or more color-changing azo dyes represented by the general formula 01 can be used in combination. The azo dye base used in the indicator ink for ethylene oxide gas sterilization of the present invention is suitably about 0.1 to 3% by weight of the entire ink. The indicator ink for ethylene oxide gas sterilization of the present invention thus produced can be directly printed on packaging materials for sterilization such as medical and surgical equipment by gravure printing or flexographic printing, or Alternatively, it is printed on paper or plastic film, and processed into adhesive labels, adhesive tapes, etc. that can be attached to the outside of packages such as medical and surgical equipment to be sterilized. These are used as markers to distinguish between sterilized packages and untreated packages in ethylene oxide gas sterilization of medical and surgical equipment. In addition, the indicator ink of the present invention can be printed on thick paper or plastic sheet and processed into a card of an appropriate shape.
It can also be used to check the sterilization status inside the package by inserting it into the center of a package of medical or surgical equipment that is sterilized with ethylene oxide gas.

The printed matter of the ethylene oxide sterilization indicator ink of the present invention not only has a hue that changes greatly between before and after sterilization treatment, but also each hue is clear, so it is suitable for non-sterilized medical use, It is easy to distinguish between packages such as surgical instruments and sterilized packages, or to check the sterilization status inside the package, and errors in judgment are less likely to occur.

As mentioned above, the printed matter of the indicator ink for ethylene oxide gas sterilization of the present invention is excellent in the degree of hue change and color clarity before and after the ethylene oxide gas sterilization treatment. When at least one of R2 or R3 in the general structural formula '1} of the azo dye used for is a phenyl group or a penzyl group, the dye is particularly excellent in terms of hue change and color clarity. The present invention will be explained in more detail below with reference to Examples, but the present invention is not limited to these Examples. Example 1 Azo dye (having the following structural formula) 1 part binder (
Rosin modified maleic acid resin) 35 parts acidic substance (phthalic acid) 1 part solvent (ethanol/isopropyl/ethyl cellosolve = 30/25/8
) Mix Isobe and dissolve the aso dye, acidic substance, and binder in a solvent to create an ink.

When this was printed on sterile paper using a flexo printing method, a clear red print was obtained. When this is sterilized with ethylene oxide gas (using a mixed gas of 2% by weight of ethylene oxide and 8% by weight of Freon at a pressure of lk9/2 and treated at 40qo for 3 hours), it becomes a clear bluish purple color. It changed color. Example 2 Azo dye (with the following structural formula) 1 part Binder (vinyl chloride-pinyl acetate-monohydroaleic acid copolymer)
28 parts acidic substance (trimellitic acid) 1 part solvent (M old K/MIBK
= 1/1) Mix the 7 capitals and dissolve the azo dye, acidic substance, and binder in a solvent to create ink.

When 50 parts of a solvent (M old K/MIBK=1/1) was added to this and printed on sterile paper using a gravure printing method, a clear light-colored print was obtained. This was sterilized with ethylene oxide gas (using a mixed gas of 2% by weight of ethylene oxide and 8% by weight of carbon dioxide at a pressure of 2k9/m, 55% by weight).
After processing for 3 hours at ℃), the printed matter turned bright purple. Example 3 An ink was prepared in the same manner as in Example 2 except that an azo dye having the structural formula shown in the left column below was used, and the hue change and hue when the printed material was sterilized with ethylene oxide gas The clarity (before and after sterilization) is shown in the table below.

Claims (1)

[Claims] 1 General formula ▲ Numerical formula, chemical formula, table, etc. group, benzylthio group, and lower alkylsulfonyl group. ▲There are mathematical formulas, chemical formulas, tables, etc.▼ is a benzene nucleus, and R_2 and R_3 each represent a hydrogen atom, a lower alkyl group, a substituted lower alkyl group, a phenyl group, and a benzyl group. R_2 and R_3 may be combined to form a ring. In addition, the benzene nucleus ▲There are mathematical formulas, chemical formulas, tables, etc.▼ may have non-dissociable substituents. ] 1,3,4-thiadiazole ring and P-
1. An indicator ink for ethylene oxide gas sterilization, characterized in that an azo dye containing an aniline or aniline derivative structure coupled at a position is used as a color-changing colorant. 2. The indicator for ethylene oxide gas sterilization according to claim 1, characterized in that an azo dye in which at least one of R_2 and R_3 in general formula (1) is a phenyl group or a benzyl group is used. ink.