JP5390299B2 - Package with high-pressure steam sterilization indicator - Google Patents

Description

  The present invention relates to a package with a high-pressure steam sterilization indicator.

  High pressure steam sterilization is used in medical and food applications. In medical applications, it is used for sterilization of pharmaceuticals such as infusions, hygiene products such as gauze, medical equipment and instruments, etc., and in food applications, it is also used for sterilizing retort foods such as curry, stew, porridge, and soup. However, an autoclave sterilization indicator is used to confirm whether or not these autoclaves have been performed.

  For example, Patent Document 1 discloses a retort packaging material film in which a base film and an outer layer film are bonded via a laminate layer, and an indicator ink layer is formed on at least a part of an adhesive surface with the laminate layer. Yes. Patent Documents 2 to 4 also disclose a similar laminated body or package with an indicator.

JP 2003-334897 A JP 2005-022173 A JP 2005-177881 A JP 2006-219135 A

In the laminated body or package of Patent Documents 1 to 4, when the inner layer film peels off or breaks when the high pressure steam sterilization is performed after packaging the medicine or food to be sterilized, the indicator is displayed. There was a risk of contamination with the contents.
In addition, because the indicator is installed above the contents, the color of the indicator is difficult to understand depending on the color of the contents.
Furthermore, when the indicator is installed only in a part where the contents are not contaminated even if the inner layer film is peeled off or broken, for example, only in the heat seal part, the indicator is required to have heat resistance that does not change color by the heat seal process. .

  Therefore, the present invention provides a high-pressure steam sterilization indicator having a distinctiveness that is not affected by the color of the contents without causing the indicator to contaminate the contents, clearly changing the color in the high-pressure steam sterilization process without being discolored in the heat seal process. It is an object of the present invention to provide an attached package and an indicator ink used therefor.

  As a result of intensive research in view of the problems of the prior art, the present inventor has installed an indicator only in the heat seal portion in a package with a high pressure steam sterilization indicator, and the indicator is not discolored by heat seal, but the high pressure The present inventors have found that the above object can be achieved by clearly discoloring in steam sterilization, and have completed the present invention.

That is, the present invention
(1) A package formed by heat-sealing a film in which a heat-sealable film is laminated on a film base material, and includes a polyurethane resin, a methine dye and / or a cyanine dye, and a resin having a carboxyl group A package with a high-pressure steam sterilization indicator, wherein the indicator ink is applied to at least a part of the heat seal part of the film base,
(2) The package with a high-pressure steam sterilization indicator according to claim 1, wherein the heat-sealable film is an unstretched polyolefin film ,
(3) The high-pressure steam according to claim 1 or 2, wherein the polyurethane resin is synthesized from a polyol, a polyisocyanate compound and a chain extender and has a number average molecular weight of 3,000 to 150,000. Package with sterilization indicator,
(4) The package with a high-pressure steam sterilization indicator according to any one of claims 1 to 3, wherein the resin having a carboxyl group is rosin or a rosin derivative having an acid value of 20 or more ,
It is.

  According to the present invention, since the indicator is installed only in the heat seal part, even if the package is peeled off or broken, there is no risk that the indicator will come into contact with the contents and become contaminated, and the color does not change under heat seal conditions. Since the color changes clearly under high-pressure steam sterilization conditions and the color development is not affected by the color of the contents, a package with a high-pressure steam sterilization indicator excellent in distinguishability and an indicator ink used therefor can be provided.

  Hereinafter, embodiments for carrying out the present invention will be described in detail. Note that this embodiment is merely an embodiment for carrying out the present invention, and the present invention is not limited by this embodiment, and various modified embodiments can be made without departing from the gist of the present invention. Is possible.

  The package with a high-pressure steam sterilization indicator of the present invention is a package formed by heat-sealing a film in which a heat-sealable film is laminated on a film substrate, wherein the indicator ink is a heat-seal portion of the film substrate. It is applied to at least a part.

  More specifically, the packaging body applies the indicator ink only to at least a part of the heat seal portion (usually considered to be the outer edge portion) of the film base material, and then laminates the heat sealable film thereon. Thus, the film with an indicator is obtained, and the film with an indicator is further folded or overlapped to seal the heat seal portion. By doing so, since the indicator is present only in the heat seal portion, it does not come into contact with the contents even when the package is peeled or broken, and it can be visually recognized that the color is clearly changed regardless of the contents.

  The film base material to which the indicator ink is applied does not have to be a single layer, and can be a laminated film of two or more layers by laminating. Moreover, after apply | coating indicator ink to this film base material, 1 or more layers of films are laminated | stacked as an intermediate | middle layer, and a heat-sealable film can be laminated on it, and it can also be set as a film with an indicator.

  Furthermore, after applying the indicator, a film with an indicator may be obtained by sequentially forming a white ink layer and a heat seal layer. Since the white ink layer serves as a background, the discoloration of the indicator after the high-pressure steam sterilization treatment can be visually recognized more clearly, and the contents can be concealed.

  The white ink is not particularly limited as long as it is an ink containing a binder resin and a white pigment. What is marketed may be sufficient, for example, LG-NT631R white S (made by Tokyo Ink Co., Ltd.) etc. are mentioned.

  A known method can be used for the lamination, and a method of laminating a heat-sealable film through an adhesive is preferable. For example, an extrusion laminating method, a dry laminating method, a wet laminating method, and a non-solvent laminating method can be mentioned, and a dry laminating method excellent in heat resistance is particularly preferable.

  The package with a high-pressure steam sterilization indicator of the present invention can be obtained by sealing the outer edge portion of the film with an indicator. Although there is no restriction | limiting in particular about a sealing system, The heat sealing system with high airtightness and load resistance is preferable.

  Examples of the heat seal method include a hot plate seal, a belt seal, and an impulse seal method, but there is no particular limitation as long as sufficient sealability and strength can be obtained.

  The heat seal conditions (temperature, pressure and time) are appropriately determined depending on the type of heat sealable film, but are not particularly limited as long as a desired strength is obtained and there is no appearance defect after heat seal. Since the indicator ink of the present invention has high heat resistance, it does not change color under the heat seal conditions of polypropylene or polyethylene usually used as a heat seal resin. For example, even at 250 ° C., which is the highest temperature in polypropylene heat sealing, the color does not change when the heating time is 0.2 seconds and is repeated about three times. Therefore, when a package is produced by heat sealing, the present invention can be applied to a package having a complicated shape because it is not discolored even in a portion that is heated a plurality of times such as an overlapping portion.

  The indicator ink of the present invention includes a polyurethane resin, a methine dye and / or a cyanine dye, and a resin having a carboxyl group.

  The polyurethane resin is preferably synthesized from a polyol, a polyisocyanate compound and a chain extender and has a number average molecular weight of 3,000 to 150,000. Especially, the range of 5,000-100,000 is especially preferable. If it is less than 3,000, the drying property of the indicator ink and the blocking resistance of the coated material coated with the indicator ink are lowered. On the other hand, when it exceeds 150,000, the storage stability, production suitability, and printability of the indicator ink are lowered. In addition, the number average molecular weight in this specification is a measured value by GPC method (polystyrene conversion).

  Examples of the polyol include polyester polyols, polyether polyols, polymer polyol compounds, saturated or unsaturated low molecular diols, low molecular polyols, and the like, which can be appropriately selected and used. Of these, polyester polyols and polyether polyols are preferred. Polyester polyol alone or a mixture of polyester polyol and polyether polyol may be used.

The polyester polyol is obtained, for example, by a condensation reaction between a diol and a dicarboxylic acid. Examples of the diol include ethylene glycol, diethylene glycol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, 1,5-pentanediol, and 1,6-hexanediol. , Triethylene glycol, trimethylene glycol, 1- or 2-methyl-1,3-butanediol, 1- or 2-methyl-1,4-pentyl glycol, 2-methyl-2,4-pentanediol, 3- Methyl-1,5-pentanediol, 2,4-diethyl-1,5-pentanediol, 2,2,4-trimethyl-1,3-pentanediol, 2-ethyl-1,3-hexanediol, 2, 5-dimethyl-2,5-hexanediol, 2,5-dimethyl-3,4-hexanediol, isobutylene glycol Coal, 2-methyl-1,3-propanediol, tripropylene glycol, 1,2-propylene glycol, neopentyl glycol, butylethylpropanediol, 2-ethyl-2-butyl-1,3-propanediol, 2- Examples thereof include methyl-2-propyl-1,3-propanediol, 1,4-butylenediol, 1,4-cyclohexanedimethanol, 1,4-butanediol, 1,4-butenediol and the like. In addition, a part of diol component can be changed to a polyfunctional polyol. Examples thereof include glycerin, trimethylolpropane, trimethylolethane, 1,2,6-hexanetriol, 1,2,4-butanetriol, sorbitol, pentaerythritol and the like.
Examples of dicarboxylic acids include adipic acid, succinic acid, sebacic acid, azelaic acid, fumaric acid, maleic acid, phthalic acid, terephthalic acid, isophthalic acid, malonic acid, oxalic acid, glutaric acid, and pimelic acid. A mixture of two or more types may be used. Of these, particularly preferred are adipic acid and sebacic acid.
The number average molecular weight of the polyester polyol is preferably in the range of 600 to 7,000. Among these, a particularly preferable range is 1,000 to 5,000. If the number average molecular weight is less than 600, the polyurethane resin may be hard and brittle, and if it exceeds 7,000, the adhesion of the indicator ink to the film decreases.

The polyether polyol can be obtained by polymerization or copolymerization of ethylene oxide, propylene oxide, tetrahydrofuran or the like. Examples thereof include polypropylene glycol, polyethylene glycol, polyoxytetramethylene glycol and the like. Of these, particularly preferred is polypropylene glycol.
The number average molecular weight of the polyether polyol is preferably in the range of 600 to 5,000. Of these, the range of 800 to 3,500 is particularly preferable. When the number average molecular weight is less than 600, the polyurethane resin may be hard and brittle, and when it exceeds 5,000, the blocking resistance of the coated product coated with the indicator ink is lowered.
The ratio of the polyester polyol to the polyether polyol is preferably in the range of 100/0 to 20/80 by weight. When the ratio of the polyester polyol to the polyether polyol exceeds 80% by weight, the anti-blocking property of the coated product coated with the indicator ink is lowered.

  In addition, other polymer polyol compounds may be used for the polyurethane resin. Examples thereof include polyester polyols obtained by ring-opening polymerization of cyclic ester compounds, polycarbonate diols, polybutadiene glycols, acrylic polyols, and the like.

  Furthermore, a saturated or unsaturated low molecular diol or low molecular polyol can also be used for the polyurethane resin. For example, ethylene glycol, 1,2-propanediol, 1,3-propanediol, 2-methyl-1,3-propanediol, 2-ethyl-2-butyl-1,3-propanediol, 1,2-butane Diol, 1,3-butanediol, 1,4-butanediol, 2,3-butanediol, neopentyl glycol, 1,2-pentanediol, 1,3-pentanediol, 1,4-pentanediol, 1, 5-pentanediol, 2,3-pentanediol, 2,4-pentanediol, 2-methyl-1,2-pentadiol, 2-methyl-1,3-pentadiol, 2-methyl-2,3-penta Diol, 4-methyl-1,3-pentanediol, 3-methyl-1,5-pentanediol, 3-methyl-2,3-pentanediol, -Methyl-1,2-pentanediol, 4-methyl-2,3-pentanediol, 1,2-hexanediol, 1,3-hexanediol, 1,4-hexanediol, 1,5-hexanediol, 1 , 6-hexanediol, 2,3-hexanediol, 2,4-hexanediol, 2,5-hexanediol, 3,4-hexanediol, 1,2-octanediol, 1,3-octanediol, 1, 4-octanediol, 1,5-octanediol, 1,6-octanediol, 1,7-octanediol, 1,8-octanediol, 2,3-octanediol, 2,4-octanediol, 2,5 -Octanediol, 2,6-octanediol, 2,7-octanediol, 3,4-octanediol, 3,5-octanediol , 3,6-octanediol, 1,4-butanediol, 1,4-butylenediol, diethylene glycol, triethylene glycol, dipropylene glycol, glycerin, trimethylolpropane, trimethylolethane, 1,2,6- Examples include hexanetriol, 1,2,4-butanetriol, sorbitol, pentaerythritol and the like.

  Examples of the polyisocyanate compound include tolylene diisocyanate, 4,4′-diphenylmethane diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate, isophorone diisocyanate, 1,3-bis (isocyanate methyl) cyclohexane, 4,4′-dicyclohexyl diisocyanate and These trimethylolpropane trimers, isocyanurates, burettes, allophanates and the like can be used, and these can be used alone or in combination of two or more. Of these, 4,4'-diphenylmethane diisocyanate, isophorone diisocyanate and the like are particularly preferable.

  Examples of the chain extender include diamine compounds such as ethylenediamine, propylenediamine, hexamethylenediamine, triethylenetetramine, diethylenetriamine, isophoronediamine, dicyclohexylmethane-4,4′-diamine, dimeramine amine, and xylylenediamine, -Hydroxyethylethylenediamine, di-2-hydroxyethylpropylenediamine, di-2-hydroxyethylethylenediamine, diamine compounds having a hydroxyl group such as di-2-hydroxyethylpropylenediamine, neopentyl glycol, butylethylpropanediol, ethylene glycol, Diethylene glycol, dipropylene glycol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, 1,6-butanediol Xanthdiol, triethylene glycol, 1- or 2-methyl-1,3-butanediol, 1- or 2-methyl-1,4-pentyl glycol, 2,4-diethyl-1,5-pentanediol, tripropylene Diol compounds such as glycol, 1,2-propylene glycol, 3-methyl-1,5-pentanediol, 2-methyl-1,3-propanediol, N-methyldiethanolamine, N-methyldiisopropanolamine, phenyldiisopropanol Diol compounds having amine groups such as amine, 4-methylphenyldiethanolamine, 4-methylphenyldiisopropanolamine, alkylene oxides such as ethylene oxide, propylene oxide, and ethylene propylene oxide of bisphenol A Such as de adducts. Of these, isophoronediamine is particularly preferable.

  In the production of the polyurethane resin, a reaction terminator or a catalyst can be used as necessary. Examples of the reaction terminator include monoalcohol compounds such as methanol, ethanol, isopropyl alcohol, normal propyl alcohol, 1-butanol, 2-butanol, butylamine, sec-butylamine, tert-butylamine, dibutylamine, monoethanolamine, diethanolamine, And monoamine compounds such as propanolamine. Examples of the catalyst include amine catalysts such as triethyleneamine and triethylenediamine, tin catalysts such as dibutyltin dilaurate, dioctyltin dilaurate and tin (II) octylate, and titanium catalysts such as tetrabutyl titanate.

  The polyurethane resin is preferably in the range of 2 to 50% by weight in the total amount of the indicator ink. Among these, the range of 3 to 20% by weight is particularly preferable. If it is less than 2% by weight, the laminate suitability and / or high-pressure steam sterilization resistance of the film with an indicator is lowered. If it exceeds 50% by weight, viscosity or fluidity suitable for printing cannot be obtained.

  A diluted solvent can be used for the polyurethane resin (hereinafter, the polyurethane resin diluted with the solvent is referred to as “polyurethane resin solution” in this specification). For example, aromatic hydrocarbon solvents such as toluene and xylene, alcohol solvents such as methanol, ethanol, isopropyl alcohol, normal propyl alcohol, and butanol, ethyl acetate, propyl acetate, isopropyl acetate, butyl acetate, isobutyl acetate, sec-butyl acetate And ester solvents such as tert-butyl acetate, and ketone solvents such as acetone, methyl ethyl ketone, methyl isobutyl ketone, and cyclohexanone. These can be used alone or in combination of two or more. Of these, toluene, ethyl acetate, propyl acetate, isopropyl alcohol, methyl ethyl ketone and the like are particularly preferable.

  As a method for producing the polyurethane resin solution, a known method represented by a two-step reaction method, a one-step reaction method, or a method combining a one-step reaction method and a two-step reaction method can be used. The two-stage reaction method is a preferable production method in that it is easy to obtain a uniform polymer.

  The viscosity of the polyurethane resin solution is preferably in the range of 50 to 100,000 mPa · s / 25 ° C. for handling. Moreover, it is preferable that the amine value of a polyurethane resin solution exists in the range of 0.1-10 mgKOH / g.

  Examples of the methine dyes and / or cyanine dyes used in the indicator ink include Color Index Basic Red 12, 13, 14, 15, 27, 35, 36, 37, 45, 48, 49, 52, 53, 66 and 68, CI Basic Yellow 11, 12, 13, 14, 21, 22, 23, 24, 28, 29, 33, 35, 40, 43 44, 45, 48, 49, 51, 52 and 53, CI Basic Violet 7, 15, 16, 20, 21, 39 and 40, Color Index Orange (C.I. Basic Orange) 27, 42, 44 and 46, color index Such as Basic Blue (C.I.Basic Blue) 62 and 63, and the like. Of these, Color Index Basic Red 12, 13, 14, 15 and 37, Color Index Basic Yellow 11 and 13, Color Index Basic Violet 7 and 15 and the like are particularly preferable in discoloration. These can be used alone or in combination of two or more.

  The methine dye and / or cyanine dye in the total amount of the indicator ink is preferably in the range of 0.1 to 5% by weight. Of these, the range of 0.2 to 3% by weight is particularly preferable. If it is less than 0.1% by weight, sufficient color development is not exhibited, and if it exceeds 5% by weight, the hue change after discoloration is poor.

The acid value of the resin having a carboxyl group used for the indicator ink is preferably 20 or more. Among these, 30 or more is particularly preferable. Thereby, when the indicator ink is applied, an excellent color forming effect of the methine dye and / or cyanine dye can be obtained.
The softening point of the resin having a carboxyl group is preferably 60 ° C. or higher. Among these, 80 ° C. or higher is particularly preferable. When the softening point is less than 60 ° C., the blocking resistance of the coated material coated with the indicator ink is lowered.

  The resin having a carboxyl group is, for example, rosin, hydrogenated rosin, polymerized rosin, rosin maleic acid modified product and its ester compound, rosin fumaric acid modified product and its ester compound, rosin acrylic acid modified product and its ester compound Rosin esterified resin, disproportionated rosin and the like. Thereby, a clear discoloration effect of the methine dye and / or cyanine dye in the high-pressure steam sterilization treatment can be obtained.

  The resin having the carboxyl group in the total amount of the indicator ink is preferably in the range of 0.1 to 30% by weight. Among these, the range of 1 to 25% by weight is particularly preferable. If it is less than 0.1% by weight, a clear discoloration effect of the methine dye and / or cyanine dye cannot be obtained in the high-pressure steam sterilization treatment. On the other hand, if it exceeds 30% by weight, the blocking resistance of the coated product coated with the indicator ink is lowered.

  The ratio of the polyurethane resin to the resin having a carboxyl group is preferably in the range of 95/5 to 10/90 by weight. Especially, the range of 90 / 10-20 / 80 is especially preferable. When the polyurethane resin exceeds 95% by weight by blending the polyurethane resin and the carboxyl group-containing resin, a clear discoloration effect of the methine dye and / or cyanine dye in the high-pressure steam sterilization treatment is obtained. In addition, if the resin having a carboxyl group exceeds 90% by weight, the laminate suitability and / or high-pressure steam sterilization resistance of the film with an indicator deteriorates.

  In addition to polyurethane resins, methine dyes and / or cyanine dyes and resins having a carboxyl group, the indicator inks of the present invention include other resins, invariant colorants (color hues by high-pressure steam sterilization treatment) as necessary. Dyes that do not change), additives, other solvents, and the like.

  Other resins can be used for the purpose of improving the performance and film properties of the indicator ink. For example, nitrified cotton, acrylic resin, polyamide resin, vinyl chloride-vinyl acetate copolymer, polyester resin, chlorinated polypropylene resin, chlorinated ethylene-vinyl acetate resin, rosin modified resin, phenol resin, ethylene-vinyl acetate resin, alkyd resin , Butyral resin, ketone resin and the like.

  The invariant colorant is not particularly limited as long as it has heat resistance and migration resistance capable of withstanding high-pressure steam sterilization. Pigments and dyes can be appropriately selected and used within a range in which the hue of methine dyes and / or cyanine dyes can be clearly recognized before and after high-pressure steam sterilization.

  Examples of the permanent color pigment include, for example, titanium oxide, dial, barium sulfate, calcium carbonate, silica, zinc oxide, zinc sulfide, mica, talc, carbon black and other inorganic pigments, phthalocyanine-based, insoluble azo-based, condensed Examples thereof include organic pigments such as azo, dioxazine, anthraquinone, quinacridone, perylene, Paynon, and thioindigo. The dye is preferably one that dissolves or disperses in an organic solvent and does not react under alkalinity. For example, Color Index Direct Yellow (CI Direct Yellow) 12, 27 and 98, Color Index Direct Red (CI Direct Red) 1, 4 and 28, Color Index Direct Orange (C.I. (Direct Orange) 8, 26 and 29, CI Direct Brown 2, 44, 58, 106 and 209, CI Acid Orange 74, Color Index CI Acid Red 111, Color Index Acid Blue 113, 117 and 120, Color Index Acid GREEN (C.I. Acid Green) 9, 19 and 44, C.I. Acid Brown 13, C.I.Mordant Brown 19, C.I. Color Brown Disper Thread (CI Disperse Red) 9, Color Index Solvent Yellow (C.I. Solvent Yellow) 16, 21, 29, 56 and 61, Color Index Solvent Orange (CI Solvent Orange) 12, 14, 37 and 40, Color Index Solvent Red (CI Solvent Red) 1, 8, 23, 30, 49, 81, 82, 83, 84, 100, 109 and 121, Color Index CI Solvent Blue 5, 12 and 70, CI Solvent Biolet 8, 21 and 27, CI Solvent Brown 20, etc. Is mentioned. The invariant colorant is not particularly limited as long as the hue of the methine dye and / or cyanine dye is clearly recognizable before and after autoclaving. It is preferable to add in the range of 0.1 to 30% by weight in the total amount of the indicator ink.

  As the additive, an antifoaming agent, a leveling agent, an anti-blocking agent, a wax, a pigment dispersant and the like are appropriately selected for the purpose of improving the printability and film properties of the indicator ink within a range not deteriorating the indicator function. Can be used.

  Any other solvent may be used as long as it dissolves and / or disperses components constituting the indicator ink and maintains fluidity, and a known organic solvent, water, and the like can be appropriately selected and used.

  Examples of the organic solvent include aromatic hydrocarbon solvents such as toluene and xylene, aliphatic hydrocarbon solvents such as hexane, cyclohexane, methylcyclohexane, and ethylcyclohexane, methanol, ethanol, isopropyl alcohol, normal propyl alcohol, 1- Alcohol solvents such as butanol, 2-butanol, isobutanol, tert-butanol, ethyl acetate, propyl acetate, isopropyl acetate, butyl acetate, isobutyl acetate, sec-butyl acetate, ester solvents such as tert-butyl acetate, acetone, Ketone solvents such as methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone, ethylene glycol monomethyl ether, ethylene glycol monoethyl ether, ethylene glycol monodimethyl Examples include ethers, glycol ether solvents such as ethylene glycol monobutyl ether, propylene glycol monomethyl ether, propylene glycol monoethyl ether, propylene glycol monopropyl ether, propylene glycol monobutyl ether, and esterified products thereof. For example, ethylene glycol monomethyl ether acetate, ethylene glycol monoethyl ether acetate, ethylene glycol monobutyl ether acetate, diethylene glycol monoethyl ether acetate, diethylene glycol monobutyl ether acetate, propylene glycol monomethyl ether acetate, propylene glycol monoethyl ether Etc. Le acetate and the like, can be used in combination singly or two or more kinds. The solvent is preferably in the range of 50 to 98% by weight in the total amount of the indicator ink. Of these, particularly preferred is the range of 60 to 95% by weight.

  The indicator ink of the present invention uniformly dissolves and / or disperses a polyurethane resin solution, a methine dye and / or a cyanine dye, a resin having a carboxyl group, other resins, an invariant colorant, and an additive in a solvent. Can be manufactured. A stirrer or a disperser can be used as a production machine for dissolving and / or dispersing, and examples thereof include a dissolver, a roll mill, a ball mill, a bead mill, and an attritor. In the case where bubbles or coarse particles are contained in the indicator ink, it is preferably removed using a known filter or the like in order to reduce the printability and the quality of the printed matter.

  The viscosity of the indicator ink of the present invention is not particularly limited as long as it does not interfere with printing. Considering the production suitability and handling of the indicator ink, the range of 10 to 1,000 mPa · s / 25 ° C. is preferable.

  The indicator ink of the present invention is applied to at least a part of the heat-sealed portion of the film substrate. As the coating method, it can be selected from known printing or coating, spraying, etc., for example, silk screen printing method, gravure printing method, offset printing method, flexographic printing method, roller coater method, brush coating method, spray method, For example, the knife jet coater method. Of these, the gravure printing method or the flexographic printing method is preferable because of its high quality and high productivity.

  In the case of printing, printing can be performed as it is. However, according to the printing method, printing conditions, printing effect, 3 (manufactured by Kogaisha Co., Ltd.) can be used by adjusting to a desired viscosity by diluting with a diluent solvent. The viscosity in this case is preferably in the range of 12 to 40 seconds. The diluent solvent may be any one as long as it can be used by adjusting the viscosity of the indicator ink, and examples thereof include organic solvents and water, and commercially available diluent solvents can also be used.

  The thickness of the indicator ink layer applied to the film substrate of the present invention is particularly limited as long as it has a sufficient degree of coloring before and after the high-pressure steam sterilization treatment and the color change can be clearly recognized. However, it is preferably within the range of 0.01 to 10 μm. Of these, the range of 0.1 to 3 μm is particularly preferable. If it is less than 0.01 μm, a sufficient concentration cannot be obtained, and if it exceeds 10 μm, the blocking resistance of the coated material coated with the indicator ink is lowered.

  When the indicator ink of the present invention is printed using a multi-color machine, it is possible to simultaneously print an in-line pattern in addition to the indicator ink. For example, the company name of the manufacturer, the product name, the contents, the component display, the design such as sales promotion, and the pseudo display of the hue before and after the color change of the indicator.

  The indicator ink of the present invention can be printed even under the condition of one liquid that is printed by adding a diluent solvent as it is, but can also be printed under the condition of two liquids in which a polyisocyanate curing agent is added thereto. In printing with two liquids, the heat resistance, water resistance, adhesion and the like of the indicator ink are improved, and this is preferable in that a film with an indicator that is resistant under high-pressure steam sterilization conditions can be obtained.

  Examples of the polyisocyanate curing agent include tolylene diisocyanate, 4,4′-diphenylmethane diisocyanate, hexamethylene diisocyanate, xylylene diisocyanate, isophorone diisocyanate, 1,3-bis (isocyanate methyl) cyclohexane, 4,4 ′. -Modified forms such as dicyclohexyl diisocyanate and their trimethylolpropane trimer, isocyanurate, burette, and allophanate, and the like can be used alone or in combination of two or more.

  Examples of the film base material used for the package with a high-pressure steam sterilization indicator include polyester films such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN), polyolefin films such as polyethylene and polypropylene, polystyrene films, ethylene-vinyl alcohol, Transparent film with polyvinyl alcohol and other alcoholic films, polyamide film or barrier polyamide film with a barrier layer in the middle, polycarbonate film, polyacrylonitrile film, polyimide film, PET film or polyamide film with a deposition layer such as alumina or silica Evaporated polyester film or transparent evaporated polyamide film, polyvinylidene chloride resin, polyvinyl alcohol resin , Various coating films obtained by coating such as polyacrylic acid resins and the like, which stretch may be either unstretched, or may be laminated alone or two or more kinds. These can be selected appropriately in consideration of mechanical strength and dimensional stability. Further, in order to improve the adhesion of the indicator ink on the surface on which the indicator ink layer is applied, a corona treatment, a low-temperature plasma treatment, a flame treatment, a solvent treatment, a coating treatment, or the like can be selected. Among these, a biaxially stretched PET film, a polyamide film, or a vapor deposition film in which a vapor deposition layer such as alumina or silica is provided thereon is particularly preferable.

  The thickness of the film substrate is not particularly limited as long as it does not interfere with printability, winding property, and the like, but is preferably within a range of 5 to 200 μm. Of these, particularly preferred is a range of 6 to 30 μm.

  The intermediate layer can be laminated by laminating the film base material coated with the indicator ink. This intermediate layer can be provided as necessary for imparting pinhole resistance, light shielding properties, gas barrier properties, fragrance retention, and the like. For example, a polyester film such as polyethylene terephthalate (PET) or polyethylene naphthalate (PEN), a transparent deposited polyester or transparent deposited polyamide film, an alcohol-based film such as ethylene-vinyl alcohol or polyvinyl alcohol, a polyamide film or a barrier layer is disposed in the middle Examples include barrier polyamide films, polyvinylidene chloride resins, polyvinyl alcohol resins, various coating films coated with polyacrylic acid resins, metal foils such as aluminum foil, and paper. In order to improve the adhesion, a corona treatment, a low-temperature plasma treatment, a flame treatment, a solvent treatment, a coating treatment, or the like can be applied, or a pre-treated one can be selected. From the viewpoint of cost and versatility, the corona treatment is particularly preferable, and treatment is performed on both sides.

  The thickness of the intermediate layer is not particularly limited as long as it does not interfere with workability and cost, but is preferably within a range of 3 to 200 μm. Of these, the range of 5 to 30 μm is particularly preferable.

  As the heat-sealable film used for the package with the high-pressure steam sterilization indicator of the present invention, any film that can be heat-sealed at a temperature of 250 ° C. or lower can be used. For example, polypropylene, polyethylene, ethylene vinyl acetate, ethylene-methacrylic acid copolymer, ethylene-methacrylic acid ester copolymer, ethylene-acrylic acid copolymer, ethylene-acrylic acid ester copolymer, and resins of these metal cross-linked products An unstretched film such as an unstretched polypropylene film or a polyethylene film is preferable.

  The thickness of the heat-sealable film is not particularly limited as long as it is within the range that does not hinder the winding property and cost, but is preferably within the range of 10 to 200 μm. Of these, particularly preferred is a range of 20 to 80 μm.

  EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention concretely, it is not limited only to a following example etc. In Examples and the like, “parts” and “%” represent “parts by weight” and “% by weight” unless otherwise specified.

(Synthesis Example 1)
A four-necked flask equipped with a stirrer, a condenser, a thermometer, and a nitrogen gas inlet tube was charged with 600 parts of 3-methyl-1,5-pentaneadipatediol having a number average molecular weight of 3,000 and a number average molecular weight of 3,000. 150 parts of neopentyl glycol adipate diol, 250 parts of polypropylene glycol having a number average molecular weight of 3,000, and 144.8 parts of isophorone diisocyanate were charged and reacted at 105 ° C. for 6 hours while introducing nitrogen gas. 2.3%) was obtained. To this urethane prepolymer, 763 parts of methyl ethyl ketone was added to obtain a uniform urethane prepolymer resin solution A′1,907.8 parts. Subsequently, 1,000 parts of the urethane prepolymer resin solution A ′ is gradually added to a mixture comprising 25.5 parts of isophoronediamine, 5.2 parts of dibutylamine, 630.3 parts of methyl ethyl ketone, and 442 parts of isopropyl alcohol at room temperature. Then, the mixture was heated to 60 ° C. and reacted for 3 hours to obtain a polyurethane resin solution A. The obtained polyurethane resin solution A had a resin solid content of 30%, a viscosity of 1,050 mPa · s / 25 ° C., an amine value of 0.4 mgKOH / g, and a number average molecular weight of 9,500.

(Synthesis Example 2)
A four-necked flask equipped with a stirrer, a condenser, a thermometer, and a nitrogen gas inlet tube was charged with 666 parts of 3-methyl-1,5-pentaneadipatediol having a number average molecular weight of 2,000 and 2,000 parts having a number average molecular weight of 2,000. 334 parts of polypropylene glycol and 200 parts of 4,4′-diphenylmethane diisocyanate were charged and reacted at 105 ° C. for 6 hours while introducing nitrogen gas to obtain a urethane prepolymer (isocyanate content 2.1%). To this urethane prepolymer, 800 parts of ethyl acetate was added to obtain 2,000 parts of a uniform urethane prepolymer resin solution B ′. Subsequently, 1,000 parts of the urethane prepolymer resin solution B ′ is gradually added to a mixture of 24.7 parts of isophoronediamine, 2.6 parts of dibutylamine, 625.7 parts of ethyl acetate, and 440 parts of isopropyl alcohol at room temperature. Then, the mixture was heated to 60 ° C. and reacted for 3 hours to obtain a polyurethane resin solution B. The obtained polyurethane resin solution B had a resin solid content of 30%, a viscosity of 950 mPa · s / 25 ° C., an amine value of 0.5 mgKOH / g, and a number average molecular weight of 10,200.

Example 1
20 parts of polyurethane resin solution A, 15 parts of hydrogenated rosin (acid number 170, softening point 85 ° C.), 1 part of basic red 37, 50 parts of propyl acetate, 4 parts of methyl ethyl ketone and 10 parts of isopropyl alcohol are mixed for 3 hours to obtain red Indicator ink no. 1 was obtained. Indicator ink No. 1 is gravure-printed on a 12 μm PET film, and then a 15 μm polyamide film as an intermediate layer is dry-laminated with a two-component curable urethane adhesive A-525 / A-52 (Mitsui Chemical Polyurethane Co., Ltd.) The film with an indicator was obtained by laminating by a method, and further laminating a 60 μm unstretched polypropylene film having heat sealability. After aging at 50 ° C. for 6 days, the heat-sealable film surfaces of the indicator-attached film were put together, heat-sealed at 250 ° C. for 0.2 seconds, at a pressure of 3 kgf / cm ² , and filled with water as the contents. A 4-way pouch was created.

(Example 2)
10 parts of polyurethane resin solution B, 15 parts of hydrogenated rosin (acid value 168, softening point 88 ° C.), 1 part of basic red 37, 50 parts of propyl acetate, 4 parts of methyl ethyl ketone and 20 parts of isopropyl alcohol are mixed for 3 hours to give red Indicator ink no. 2 was obtained. Indicator ink No. 2 is gravure-printed on a 12 μm PET film, and then with a two-component curable urethane adhesive A-525 / A-52 (Mitsui Chemical Polyurethane Co., Ltd.), an intermediate layer of 7 μm aluminum foil and 15 μm A polyamide film was laminated by a dry laminating method, and a 60 μm unstretched polypropylene film having heat sealability was further laminated to obtain a film with an indicator. After aging at 50 ° C. for 7 days, the heat-sealable film surfaces of the indicator-attached film were put together, heat-sealed at 200 ° C. for 0.5 seconds, at a pressure of 3 kgf / cm ² , and filled with water as the contents. A 4-way pouch was created.

(Example 3)
39 parts of polyurethane resin solution, 19.5 parts of rosin (acid value 170, softening point 85 ° C.), 1.5 parts of basic red 37, 20 parts of propyl acetate and 20 parts of isopropyl alcohol are mixed for 3 hours to give a red indicator Ink No. 3 was obtained. Indicator ink No. 3 is a non-toluene-type dilution solvent PU515 (manufactured by Tokyo Ink Co., Ltd.), the viscosity is adjusted to 18 seconds with Zaan Cup # 3 (manufactured by Kikai Co., Ltd.), and gravure printing is performed on a 12 μm transparent vapor-deposited PET film Then, with a two-component curable urethane-based adhesive A-525 / A-52 (Mitsui Chemical Polyurethane Co., Ltd.), a 60 μm unstretched polypropylene film having heat sealability is laminated by a dry laminating method, A film with an indicator was obtained. After aging at 45 ° C. for 5 days, the heat-sealable film surfaces of the indicator-attached film were put together, heat-sealed at 200 ° C. for 0.5 seconds, at a pressure of 3 kgf / cm ² , and filled with water as the contents. A 4-way pouch was created.

Example 4
30 parts of polyurethane resin solution A, 15 parts of rosin (acid value 170, softening point 85 ° C.), 1.5 parts of cyanine blue pigment (Pigment Blue 15: 3), 2.5 parts of methyl ethyl ketone, 30 parts of ethyl acetate, 20 parts of isopropyl alcohol Disperse with a bead mill, add 1 part of Basic Red 37 to this and mix for 3 hours. 4 was obtained. Indicator ink No. 4 is a non-toluene dilution solvent PU515 (manufactured by Tokyo Ink Co., Ltd.), Zaan Cup # 3 (manufactured by Kikai Co., Ltd.), the viscosity is adjusted to 18 seconds, and gravure printing is performed on a 12 μm PET film. Next, with a two-component curable urethane adhesive A-525 / A-52 (manufactured by Mitsui Chemicals Polyurethanes Co., Ltd.), an unstretched polypropylene film of 60 μm having heat sealability is laminated by a dry laminating method, with an indicator. A film was obtained. After aging at 50 ° C. for 5 days, the heat-sealable film surfaces of the indicator-attached film were combined, heat-sealed at 250 ° C. for 0.5 second, and a pressure of 3 kgf / cm ² , and filled with water as the contents. A 4-way pouch was created.

(Example 5)
Indicator ink No. 2 is gravure-printed on a 12 μm PET film, followed by gravure printing with white ink LG-NT631R White S (manufactured by Tokyo Ink Co., Ltd.), then two-component curable urethane adhesive A-525 / A-52 (Mitsui Chemicals) Polyurethane Co., Ltd.) was used to laminate a 15 μm polyamide film serving as an intermediate layer by a dry lamination method, and a 60 μm unstretched polypropylene film having heat sealability was laminated to obtain a film with an indicator. After aging at 50 ° C. for 6 days, the heat-sealable film surfaces of the indicator-attached film were combined, heat-sealed at 200 ° C. for 0.5 seconds, at a pressure of 3 kgf / cm ² , and filled with water as the contents. A 4-way pouch was created.

(Example 6)
While adding the process of cooling the room temperature of the four-way pouch prepared in Example 1 to room temperature, the same place was further heat-sealed twice at 250 ° C. for 0.2 seconds at a pressure of 3 kgf / cm ² .

(Comparative Example 1)
15 parts of rosin (acid number 168, softening point 88 ° C.), 1 part of basic red 37, 50 parts of propyl acetate, 14 parts of methyl ethyl ketone and 20 parts of isopropyl alcohol were mixed for 3 hours. 5 was obtained. Indicator ink No. 5 is gravure-printed on a 12 μm PET film, and then a 15 μm polyamide film serving as an intermediate layer is dry-laminated with a two-component curable urethane adhesive A-525 / A-52 (Mitsui Chemical Polyurethane Co., Ltd.) The film with an indicator was obtained by laminating by a method, and further laminating a 60 μm unstretched polypropylene film having heat sealability. After aging at 50 ° C. for 6 days, the heat-sealable film surfaces of the indicator-attached film were combined, heat-sealed at 200 ° C. for 0.5 seconds, at a pressure of 3 kgf / cm ² , and filled with water as the contents. A 4-way pouch was created.

(Comparative Example 2)
20 parts of polyurethane resin solution B, 1 part of basic red 37, 50 parts of propyl acetate, 9 parts of methyl ethyl ketone and 20 parts of isopropyl alcohol were mixed for 3 hours. 6 was obtained. Indicator ink No. 6 is gravure-printed on a 12 μm PET film, and then with a two-component curable urethane adhesive A-525 / A-52 (Mitsui Chemical Polyurethane Co., Ltd.), an intermediate layer of 7 μm aluminum foil and 15 μm A polyamide film was laminated by a dry laminating method, and a 60 μm unstretched polypropylene film having heat sealability was further laminated to obtain a film with an indicator. After aging at 50 ° C. for 5 days, the heat-sealable film surfaces of the indicator-attached film were combined, heat-sealed at 250 ° C. for 0.5 second, and a pressure of 3 kgf / cm ² , and filled with water as the contents. A 4-way pouch was created.

(Comparative Example 3)
35 parts of TPH medium (polyamide-based medium manufactured by Tokyo Ink Co., Ltd.), 8 parts of hydrogenated rosin (acid value 168, softening point 88 ° C.), 0.8 part of basic red 37, 20 parts of ethyl acetate, 10 parts of toluene, 20 parts of isopropyl alcohol and 6.2 parts of normal propyl alcohol were mixed for 3 hours to obtain red indicator ink No. 7 was obtained. Indicator ink No. 7 is gravure-printed on a 12 μm PET film, and then a 15 μm polyamide film serving as an intermediate layer is dry-laminated with a two-component curable urethane adhesive A-525 / A-52 (Mitsui Chemical Polyurethane Co., Ltd.). The film with an indicator was obtained by laminating by a method, and further laminating a 60 μm unstretched polypropylene film having heat sealability. After aging at 50 ° C. for 6 days, the heat-sealable film surfaces of the indicator-attached film were put together, heat-sealed at 250 ° C. for 0.2 seconds, at a pressure of 3 kgf / cm ² , and filled with water as the contents. A 4-way pouch was created.

(Comparative Example 4)
13 parts of bismuth oxide, 20 parts of thiourea, 7 parts of talc, 65 parts of LG-NT R medium (polyurethane medium manufactured by Tokyo Ink Co., Ltd.) and 17 parts of ethyl acetate were mixed. 8 was obtained. Indicator ink No. 8 is gravure-printed on a 12 μm PET film, and then a 15 μm polyamide film serving as an intermediate layer is dry-laminated with a two-component curable urethane adhesive A-525 / A-52 (Mitsui Chemical Polyurethane Co., Ltd.). The film with an indicator was obtained by laminating by a method, and further laminating a 60 μm unstretched polypropylene film having heat sealability. After aging at 50 ° C. for 6 days, the heat-sealable film surfaces of the indicator-attached film were combined, heat-sealed at 200 ° C. for 0.5 seconds, at a pressure of 3 kgf / cm ² , and filled with water as the contents. A 4-way pouch was created.

  The following performance evaluation was performed using the film with an indicator and the four-way pouch obtained in Examples 1 to 5 and Comparative Examples 1 to 4, and the four-way pouch obtained in Example 6.

[Lamination suitability of film with indicator]
Film with indicator is cut to 15mm width, and the film base material and the bonded base material (intermediate layer and / or heat-sealable film) for forming the indicator ink layer are Tensilon Universal Testing Machine (Orientec Co., Ltd.) T-type peeling was performed at a pulling speed of 300 mm / min, and the tensile strength (degree of cutting by pulling) of the film with an indicator was measured. If the measured value is 200 g or more, it is judged that the strength is sufficient for retort use. Good laminate suitability: ○, if less than 200 g, it is judged that it does not have sufficient strength for retort use. X.

[Discoloration by heat seal]
The discoloration of the heat seal part of the four-way pouch was visually confirmed, and evaluation was made with ○ indicating no discoloration and × indicating discoloration.

[Performance evaluation of packaging bags with indicators]
The autoclave was subjected to high-pressure steam sterilization at a steam temperature of 121 ° C. for 30 minutes, and the state after the treatment was visually confirmed for the clarity of the hue change and the appearance abnormality of the four-way pouch. Evaluations were evaluated as “Good” for “Excellent” and “Poor” for poor.

The above evaluation results are summarized in Table 1.
As shown in Table 1, the films with indicators of Examples 1 to 6 had sufficient laminate suitability, the hue clearly changed before and after the high-pressure steam sterilization treatment, and there was no abnormality in appearance. Moreover, it turns out that it did not discolor in heat sealing, but discolored only when the high pressure steam sterilization process. In Example 6, the heat seal condition was repeated three times, but the heat seal part did not change color.

  On the other hand, although it is a comparative example, in comparative example 1, the retort float which swells between the film base material which forms an indicator layer, and its bonding base material generate | occur | produced, and in comparative example 2, the hue change was unclear. It was. Furthermore, in Comparative Example 3, since the laminate strength, which is the basic performance as a container, was insufficient, the evaluation other than the color development of the indicator was stopped. Moreover, although the comparative example 4 is a packaging bag with an indicator produced according to patent document 1, since a heat seal part discolored, it turns out that it cannot be used for the objective of this invention.

  The package with a high-pressure steam sterilization indicator of the present invention can be used as a package for confirming completion of high-pressure steam sterilization for medical use and food use. Moreover, since the indicator ink of this invention is excellent in heat resistance, it can be used also for a heat seal part.

Claims (4)

In a package created by heat-sealing a film in which a heat-sealable film is laminated on a film substrate,
A high-pressure steam sterilization indicator, characterized in that an indicator ink containing a polyurethane resin, a methine dye and / or a cyanine dye, and a resin having a carboxyl group is applied to at least a part of the heat seal portion of the film base. Package with attachment. The package with a high-pressure steam sterilization indicator according to claim 1, wherein the heat-sealable film is an unstretched polyolefin film . 3. The high-pressure steam sterilization indicator according to claim 1 or 2, wherein the polyurethane resin is synthesized from a polyol, a polyisocyanate compound and a chain extender, and the number average molecular weight thereof is 3,000 to 150,000. Packaging body. The package with a high-pressure steam sterilization indicator according to any one of claims 1 to 3, wherein the resin having a carboxyl group is rosin or a rosin derivative having an acid value of 20 or more .