JP2005185643A - Indicator ink composition that develops color by moisture and printing configuration using the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an indicator for urine and moisture, in which a colorant does not flow out and a color tone is conspicuous.
A water indicator ink composition containing at least an ink binder, a colorant that develops color by the action of a developer composed of a basic substance in the presence of moisture, and a pH adjuster, and a sheet containing the developer A method for laminating an ink composition on a sheet, wherein the ink composition is printed on a sheet.
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Description

  The present invention relates to a method for producing a laminated sheet having a moisture indicator function, and more particularly, to an ink composition having a moisture (urine) indicator function by visual recognition, such as a paper diaper, and a printing composition method using the same.

With the improvement of living standards and further consideration for hygiene, paper diapers and sick sheets with urine and other moisture indicators are now being used. Now, indicator inks for this purpose include those in which the design is blurred, disappears, or discolors as the colorant in the ink flows out. For example, the following Patent Documents 1 and 2 disclose urinary decoloring indicator inks.
JP-A-6-289006 JP-A-8-92511

  However, these types of indicator inks may appear to be dirty on paper diapers due to the flowing colorant. In particular, in the type of indicator ink that changes color due to the outflow of the colorant, the amount of colorant that flows out inevitably increases in order to give a difference in the color before and after the color change. In addition, since the color after the color change becomes lighter than the color before the color change, the color change due to moisture is hardly noticeable depending on the color tone. In addition, other clothing items may be colored. In the case of a decoloring type, it may be difficult to stand out.

  For this reason, moisture (urine) that is less contaminated by colorant that has flowed out after decoloring or discoloration, and lack of visibility due to the color after discoloration being lighter than the color before discoloration, and naturally harming the human body Realization of a sheet having an indicator function and a paper diaper using the sheet has been desired.

  The present invention has been made in order to solve the above-described problems, and is a basic material that is optimal as a colorant, an ink-based resin (ink binder), a hue change due to pH of the colorant, and a developer. In addition, the coloring agent is used to confirm how the coloring state of dyes and pigments changes depending on the pH, and further considering the safety and effect of the pH adjusting agent, and further becomes an ink binder. The resin is preferably dissolved in water or an alcohol-based solvent, and the dried coating has resistance to water (resistance may not be complete; it may be semi-dissolved or swelled in water). This completes the present invention.

  According to the first aspect of the present invention, there is provided a moisture indicator ink composition containing at least an ink binder, a colorant that develops color by the action of a developer composed of a basic substance in the presence of moisture, and a pH adjuster. It is a printing constitution method of an ink composition on a sheet characterized by printing on a sheet having a colorant, and the invention of claim 2 is characterized in that a filler is used as the developer. The invention according to claim 3 is a method for printing an ink composition on a sheet according to claim 3, wherein the colorant includes fluoran, erythrosin (red No. 3) (C. 1.45430), Phloxine B (red 104- 1) (C. 1.45410), Rose Bengal (Red 105-1) (C. 1.45440), Tetrachlorotetrabromofluorescein (Red 218) (C.1. 5410), tetrabromofluorescein (red 223) (C.1.4380), eosin YS (red 230-1) (C.1.4380), dibromofluorescein (orange 201) (C.1.45370). ), Fluorescein (yellow 201) (C.1.4350), uranin (yellow 202-1) (C.1.4350), eosin YSK (red 202-2) (C.1.4380), phloxine BK (Red 231) (C. 1.45410), Rose Bengal K (Red 232) (C. 1.44540), Diiodofluorescein (Orange 206) (C. 1.45425A), Erythrosine Yellow NA ( Orange No. 207) (C. 1.45425), Uranine K (Yellow No. 202-2) (C. 1.45350), Violamine R (Red) A dye having a lactone ring selected from the group consisting of (No. 01) (C. 1.45190) or capable of forming a lactone ring by pH adjustment is used. According to the invention, the ink composition for printing on a sheet having a developer composed of a basic substance, the water indicator ink composition for printing on a sheet, comprising at least an ink binder and a water content. A moisture indicator ink composition comprising a colorant that develops color under the action of a developer composed of the basic substance and a pH adjuster in the presence, and the invention according to claim 5 provides the colorant as the colorant. Fluoran, erythrosine (red No. 3) (C. 1.45430), Phloxine B (red No. 104-1) (C. 1.45410), rose bengal (red Color 105-1) (C.I. 1.44540), tetrachlorotetrabromofluorescein (red 218) (C. 1.45410), tetrabromofluorescein (red 223) (C. 145380), eosin YS (red 230-1) (C 1.45380), dibromofluorescein (orange 201) (C.1.45370), fluorescein (yellow 201) (C.1.4350), uranin (yellow 202-1) (C.1.4350) ), Eosin YSK (Red No. 203-2) (C. 1.45380), Phloxine BK (Red No. 231) (C. 1.45410), Rose Bengal K (Red No. 232) (C. 1.45440), Diiodofluorescein (orange 206) (C. 1.45425A), erythrosine yellow NA (orange 207) (C. 1.45) 25), having a lactone ring selected from the group consisting of Uranine K (Yellow 202-2) (C.1.45350), Violamine R (Red 401) (C.1.45190), or lactone by adjusting the pH The moisture indicator ink composition according to claim 4, wherein a dye capable of forming a ring is used.

  The laminated sheet obtained by the printing composition method of the present invention can be colored or discolored in the presence of moisture to visually confirm the presence of the moisture, facilitating accurate recognition of urination of infants and the like. In addition, since there is no change (discoloration) due to the outflow of the colorant, dirt is not noticeable. Further, the laminated sheet obtained by the printing composition method of the present invention can darken the color tone after discoloration due to urination of infants and the like than the color tone before discoloration, and is excellent in accurate visibility of urination of infants and the like. It is excellent as a urine (moisture) indicator for paper diapers.

  An example of the change in hue according to the present invention is as follows. The coloring matter (coloring agent) in the ink layer printed on the sheet (film) remains almost colorless by the action of the pH adjusting agent. For example, the calcium carbonate used as a developer (filler) in the film dissolves the pigment in the ink layer, and in the process, the lactone ring of the pigment is cleaved to form a calcium salt. Changes to a different hue.

  Hereinafter, the present invention will be described based on the best mode.

  The present invention comprises an ink composition comprising at least an ink binder that develops color by the action of a developer composed of a basic substance, an appropriate pH adjuster, and finally an insoluble (insoluble) water. This is a method of printing (laminating) on a sheet having the developer, and a laminated sheet having a moisture indicator function that develops color by moisture such as urine can be produced by the printing composition method of the present invention.

  Examples of the developer made of a basic substance that directly or indirectly acts on the colorant by moisture include ammonia, sodium hydrocarbon, calcium carbonate, magnesium carbonate, magnesium silicate aluminate, magnesium oxide, calcium oxide, and calcium hydroxide. , Magnesium hydroxide, calcium silicate, magnesium silicate, and coprecipitates thereof are not particularly limited. In the present invention, those conventionally used as fillers can be suitably used as the developer.

  Examples of the colorant having a mechanism that changes color by the action of the above-described basic substance in the sheet include synthetic water-soluble dyes such as direct dyes, synthetic food dyes, natural and inorganic pigments, and organic pigments. Among them, a substance whose hue such as hue and brightness changes depending on pH is used. In particular, those whose color tone changes greatly are preferred, and those which are hardly soluble in water are preferred depending on the application. More preferably, fluoran, erythrosine (Red No. 3) (C.1.4545), Phloxine B (Red No. 104-1) (C.1.445410), Rose Bengal (Red No. 105-1) (C.1) .45440), tetrachlorotetrabromofluorescein (red 218) (C. 1.45410), tetrabromofluorescein (red 223) (C. 145380), eosin YS (red 230-1) (C.I. 1.45380), dibromofluorescein (orange 201) (C.1.45370), fluorescein (yellow 201) (C.1.445350), uranin (yellow 202-1) (C.1.4350) Eosin YSK (Red No. 203-2) (C.1.45380), Phloxine BK (Red No. 231) (C.1.4541) ), Rose Bengal K (Red No. 232) (C. 1.45440), Diiodofluorescein (Orange 206) (C. 1.45425A), Erythrosine Yellow NA (Orange 207) (C. 1.45425), It has a lactone ring selected from the group consisting of uranin K (yellow 202-2) (C.1.445350), violamine R (red 401) (C.1.45190), or forms a lactone ring by adjusting the pH Dyes that can be used are used. However, the use or combination of colorants other than these is not excluded unless the effects of the present invention are impaired. The “contained in the sheet” of the present invention may be contained in the sheet, or may be applied to the sheet separately from the pigment (colorant). And a pigment | dye may be piled up and may exist in the vicinity.

  Keep the printed ink composition and the surrounding pH constant so that the ink composition printed (laminated) on the sheet having the developer does not develop color due to moisture in the air (suppressing initial coloring). An inorganic acid, an organic acid, or the like is used as a pH adjuster for maintaining the range (particularly somewhat acidic). For example, formic acid, acetic acid, phosphoric acid, succinic acid, fumaric acid, phthalic acid, terephthalic acid, benzoic acid, P-hydroxybenzoic acid, DL-malic acid, maleic acid, salicylic acid, oxalic acid, gluconic acid, citric acid , Adipic acid, tartaric acid, sorbic acid, L (+) ascorbic acid, rutin, phytic acid.

The ink binder is not particularly different from those conventionally used in ink compositions for moisture indicators, such as acrylic resin, urethane resin, butyric acetate fiber resin, nitrified cotton, polyamide resin, gum copearl, gum rosin, shellac. And vinyl chloride vinyl acetate copolymer resin. However, other materials and polymer binders can be used or used together. The ink binder is preferably a resin that dissolves in an alcohol-based solvent and has water resistance when formed into a coating film.
Components such as a developer and a colorant of the present invention can be contained in microcapsules.

  As the solvent used in the ink composition of the present invention, an alcohol solvent is mainly used. Examples of the alcohol solvent include methyl alcohol, ethyl alcohol, isopropyl alcohol, n-propyl alcohol, n-butyl alcohol, sec-butyl alcohol, isobutyl alcohol and the like. Of course, other solvents such as esters aliphatic hydrocarbons and ketones may be used or used in combination. In addition, when using together with them, the density | concentration of alcohol is not specifically limited. Therefore, it is not particularly different from those conventionally used in ink compositions as solvents.

  In addition, the ink composition of the present invention may contain an appropriate amount of an antifoaming agent, a thickener, a plasticizer, a dispersant, an emulsifier, an antioxidant, an antiseptic, or the like depending on the application. Moreover, it is also possible to mix the decoloring ink composition or the normal ink composition which does not have an indicator function with the ink composition of this invention.

  The ink composition of the present invention is obtained by mixing 0 to 1 to 20 parts by weight of the above-described colorant, 5 to 50 parts by weight of an ink binder, a pH adjuster, and an appropriate amount of a solvent. Note that this ratio may be changed in an appropriate amount depending on the application.

  As a sheet having a developer composed of a basic substance used in the present invention, for example, a large amount of the developer such as calcium carbonate described above is kneaded in a synthetic resin such as polyethylene used for a paper diaper and then stretched. Can include a developer-containing sheet (synthetic resin film) having fine holes (moisture permeability). Moreover, the sheet | seat containing the developer which consists of a basic substance used for this invention can be obtained by coating the developer which consists of a basic substance on a sheet | seat. In addition to the synthetic resin film, paper, synthetic paper, nonwoven fabric, or the like can be used.

  Printing (lamination) an ink composition containing at least a colorant, an ink binder, and a pH adjuster substance that develops color by the action of a developer composed of a base substance in the presence of moisture on a sheet containing the developer. The method of performing is not particularly limited, and a gravure printing method, a flexographic printing method, a silk screen method, and the like, depending on the composition of the ink composition, its concentration, the stage of processing of the printed material (sheet) to be used, etc. Can be appropriately selected. Moreover, although it is a to-be-printed body (sheet), as mentioned above, it is not specifically limited, For example, paper, a synthetic paper, a synthetic resin film, a nonwoven fabric etc. are mentioned.

  In addition, in order to obtain various necessary durability and performance, overcoating or undercoating may be performed when printing the ink composition on a sheet. The materials used for these overcoats and undercoats are selected appropriately depending on the application, for example, to give a little acidity to delay the color development a little, or to make it a little thicker to give sweat resistance. The

  Hereinafter, the printing configuration method of the present invention will be specifically described based on the embodiments.

  4 parts by weight of red dye 218 (tetrachlorotetrabromofluorescein) as a colorant, 10 parts by weight of shellac {manufactured by Gifu Shellac Manufacturing Co., Ltd.} as an ink binder, and 10 parts by weight of phosphoric acid as a pH adjuster, Furthermore, ethyl alcohol was added as a remaining amount to make 100 parts by weight, and these mixed liquids were stirred so as to be uniform throughout to obtain a colorless ink composition.

  Next, the obtained colorless ink composition was printed (laminated) on a moisture-permeable polyethylene film containing calcium carbonate to obtain a colorless printed matter (laminated sheet), and the following color development test was performed.

  Two folded tissue papers were stacked on the printed surface (ink composition layer) of the printed material (laminated sheet), and 2 ml of water was dropped on the printed surface (ink composition layer) and allowed to stand for 3 minutes. Thereafter, the tissue paper was removed. The colorless printed matter (laminated sheet) was colored pink.

  4 parts by weight of red dye 218 (tetrachlorotetrabromofluorescein) as a colorant, 10 parts by weight of Cyanine Blue 4034 (manufactured by Sanyo Dye Co., Ltd.), and shellac (manufactured by Gifu Shellac Co., Ltd.) as an ink binder } And 10 parts by weight of phosphoric acid as a pH adjuster, and methyl alcohol as a remaining amount to 100 parts by weight. The mixture is stirred so that the whole is uniform, and the blue ink composition I got a thing.

Next, a blue printed matter (laminated sheet) was obtained by a laminating method in which the obtained blue ink composition was printed on a moisture-permeable polyethylene film containing magnesium carbonate.
The following tests were performed using the obtained blue printed matter.
Two sheets of folded tissue paper were stacked on the printing surface (ink composition layer) of the blue printed material (laminated sheet), and 2 ml of water was dropped and allowed to stand for 3 minutes, and then the tissue paper was removed. The blue printed product had turned purple.

  Next, an experiment was conducted assuming that it was actually used for indicators such as urination. That is, the ink composition of Example 1 was printed on a sheet containing calcium carbonate for disposable diapers, and a moisture-proof sheet was put on the upper surface of the baby's skin side and attached to an infant. In this case, if there was urination, the color was surely developed.

  As mentioned above, although this invention has been demonstrated based on the preferable embodiment, of course, this invention is not limited to them at all. That is, for example, it may be as follows.

(1) For use in sheets for elderly people and long-term care patients, a protective layer and a coating layer of basic substance (developer) are provided on the top and bottom of the ink layer that develops color in the presence of moisture. Coloring with etc. is prevented.

(2) Although related to (1) above, it is possible to gradually develop color due to moisture in the air, sweating by the wearer, etc., so that it becomes a guide to know the end of the period of use and the replacement period Is possible. For this reason, the content of the pH adjusting agent and the moisture permeability of the moisture permeable sheet are also determined in consideration of the season, period of use, and the like. In addition, it is possible to attach different types of indicator ink compositions to multiple locations, change the blending ratio of pH adjuster, thickness of overcoat, etc., and change the presence or degree of coloring in each location. is there.

Claims (5)

  Printing a moisture indicator ink composition containing at least an ink binder, a colorant that develops color by the action of a developer composed of a basic substance in the presence of moisture, and a pH adjuster on a sheet having the developer. A printing configuration using an ink composition on a characteristic sheet.   The printing configuration using the ink composition on the sheet according to claim 1, wherein a filler is used as the developer.   The printing composition using the ink composition on the sheet according to claim 1 or 2, wherein a dye having a lactone ring or capable of forming a lactone ring by adjusting pH is used as the colorant. .   Moisture indicator ink composition for printing a sheet having a developer composed of a basic substance, at least an ink binder, a colorant that develops color by the action of the developer composed of the basic substance in the presence of moisture, and pH A moisture indicator ink composition comprising a regulator.   Examples of the colorant include fluoran, erythrosin (Red No. 3) (C. 1.45430), Phloxine B (Red No. 104-1) (C. 1.45410), Rose Bengal (Red No. 105-1) (C.I. 1.44540), tetrachlorotetrabromofluorescein (red 218) (C. 1.45410), tetrabromofluorescein (red 223) (C. 145380), eosin YS (red 230-1) (C 1.45380), dibromofluorescein (orange 201) (C.1.45370), fluorescein (yellow 201) (C.1.45350), uranin (yellow 202-1) (C.1.4350) ), Eosin YSK (Red No. 203-2) (C.1.45380), Phloxine BK (Red No. 231) (C.1.4541) ), Rose Bengal K (Red No. 232) (C. 1.45440), Diiodofluorescein (Orange 206) (C. 1.45425A), Erythrosine Yellow NA (Orange 207) (C. 1.45425), It has a lactone ring selected from the group consisting of uranin K (yellow 202-2) (C.1.445350), violamine R (red 401) (C.1.45190), or forms a lactone ring by adjusting the pH The water indicator ink composition according to claim 4, wherein a dye that can be used is used.