KR20110009372A - Eco friendly humidity indicating ink - Google Patents

Abstract

PURPOSE: Eco-friendly humidity indication ink is provided to enable application to an ink printing method and development of various colors and to allow a user to easily recognize humidity in the atmosphere. CONSTITUTION: Eco-friendly humidity indication ink comprises 70~99.8 wt% of indicator, 0.1~2 wt% of buffer solution, 80~99.7 wt% of humidity indication solution, 0.1~5 wt% of pigment, 0.1~3 wt% of dispersing agent, and 0.1~5 wt% of viscosity preserver. The indicator includes 95~99.5 wt% of C1~4 alcohol solvent and 0.5~5 wt% of indication reagent. The humidity indication solution comprises 0.1~25 wt% of a humidifying agent.

Description

Eco-friendly Humidity Directive Ink {Eco Friendly Humidity Indicating Ink}

The present invention relates to a humidity indicating ink having a humidity indicating function that can be used to manage humidity in the manufacturing facilities and products of the modern industry, such as electrical and electronics, home appliances, papermaking, food packaging, and so on by dissolving an indicator in an alcohol solvent. Indicators made; A buffer solution; A humidity indicator solution comprising a sodium chloride, sodium sulfate, magnesium hydroxide, polyethylene glycol (PEG), and a humectant containing at least one of glycerin; It relates to an environmentally friendly humidity indicator ink characterized by comprising a pigment, a dispersant, and a viscosity retaining agent.

Humidity control is a very important part in the manufacturing facilities and products of the modern industry, such as electrical and electronics, home appliances, paper and food packaging. Therefore, the prior art uses a humidity indicator card containing a humidity indicator solution as a digitized device or a convenient means to measure humidity and adjust humidity accordingly, except for the field where humidity must be precisely managed. Use a humidity indicator card that is easy to attach.

As the humidity indicator solution contained in the above-mentioned humidity indicator card, an aqueous solution of Cobalt (II) Chloride is usually used. However, in December 1998, in the European Union, the EU Commission Directive 98/98 / EC, the 25th Technical Regulation of the European Council Directive 67/548 / EEC, Cobalt chloride is classified as Carcinogenic Category II (potential carcinogen: no data on human body, but a carcinogenic record after inhalation of animal), and this regulation is effective from October 31, 2005, effectively using cobalt chloride solution. As a result of strong regulations on products, the sale of cobalt chloride-based products is being enforced in the future, and the demand for products to replace them is urgent. Therefore, the following conventional technologies have been studied.

Korean Patent No. 10-0676777 discloses a solution of 0.1 to 3 wt% by dissolving an indicator selected from thymol blue, methyl red, methyl orange, methyl red, neutral red, and aniline blue in ethyl alcohol in the preparation of a humidity indicating reagent. Then, 1 ~ 10 vol% of caustic soda solution was added to the solution to change the pH according to the humidity so that the color of the indicator solution was changed. The humidity indicator card is prepared by adding a solution at a concentration of 0.1 to 20 wt% and attaching the humidity indicator solution to the humidity-specific indicator printed on the blotter paper. The indicator changes color according to the change, and the auxiliary indicator uses an acid or basic reagent that adjusts the pH to change color according to the humidity. As it uses a mixture of moisture-inorganic and high molecular organic compounds to change the pH of the humidity indicator solution according to the figure, it does not contain cobalt chloride, so it is less harmful. Since the auxiliary indicator uses a simple acid or basic reagent, the pH is easily changed according to the amount of moisture absorbed or released by the moisturizer. As a result, it is difficult to expect a clear color change of the humidity indicator solution. Because of this fall, it can be used only by the impregnation method, so there is a problem in that it is difficult to apply to various fields in industrial use and difficulty in process.

In other words, the prior art humidity indicator solution composed of cobalt chloride has a high level of constraints and hazards in its manufacture and use due to the harmfulness of the harmful components, and a solution for controlling the pH change of the humidity indicator solution even in the prior art in which the cobalt component is excluded. Since general pH solution (caustic soda solution) and strong acid solution are used, the pH of the solution that adjusts the pH change according to the amount of moisture absorbed or released by the humectant is easily changed, so it is difficult to expect a distinct color change and the conventional humidity. The indicator solution is composed of only indicator, solution to control pH change, and humectant, so it has low viscosity. So, it can be applied only by impregnation method in industrial use. Because there is a problem that the color can be changed only with the color of the color, continuous research is required.

The present invention is a problem of the prior art relating to the humidity indicator solution (ink) having a humidity indicator function,

Humidity indicator solution composed of cobalt chloride has a high level of restrictions and hazards in its manufacture and use due to the harmfulness of harmful ingredients, and in the conventional technology in which cobalt ingredients are excluded, a solution for controlling the pH change of the humidity indicator solution is a general basic solution. (Caustic soda solution), because it uses a strong acid solution, the pH of the solution that adjusts the pH change according to the amount of moisture absorbed or released by the humectant is difficult to expect a distinct color change and the conventional humidity indicator solution simply It consists only of indicator, solution to adjust pH change, and humectant, so it has low viscosity properties, so it can be applied only by impregnation method in industrial use, and only by color of humidity indicator solution according to pH. Since there is a problem that color implementation is possible, it aims to provide a solution to solve this problem.

The present invention is designed to solve the problems of the prior art as described above,

70-99.8 wt% of an indicator consisting of 95 to 99.5 wt% of an alcohol solvent having 1 to 4 carbon atoms and 0.5 to 5 wt% of an indicator; 0.1-2 wt% of a buffer solution; 80 to 99.9 wt% of a humidity indicator solution containing 0.1 to 25 wt% of a sodium chloride, sodium sulfate, magnesium hydroxide, polyethylene glycol (PEG), and one or more types of glycerin; An environmentally friendly humidity indicating ink characterized by comprising a pigment 0.1 ~ 5wt%, dispersant 0.1 ~ 3wt%, viscosity maintaining agent 0.1 ~ 5wt%.

The present invention does not contain any harmful ingredients, and therefore, there is no restriction and no harmfulness in the manufacture and use, and the general basic solution (caustic soda solution) and strong acid by using a buffer solution as a solution to control the pH change of the humidity indicating solution. Since the solution is used, the pH is easily changed according to the amount of moisture absorbed or released by the humectant, and as a result, there is an effect of solving the problem of the prior art, which is difficult to expect a clear color change of the humidity indicator solution.

Humidity indicator ink containing pigment, dispersant, and viscosity retaining agent in humidity indicator solution composed of indicator, buffer solution, and humectant can be applied as ink printing method for industrial use. It is possible to realize a variety of colors and to easily recognize the humidity in the atmosphere.

The present invention is 70 to 99.9 wt% of the indicator consisting of 95 to 99.5 wt% of alcohol solvent having 1 to 4 carbon atoms, 0.5 to 5 wt% of indicator; 0.1-2 wt% of a buffer solution; 80 to 99.9 wt% of a humidity indicator solution containing 0.1 to 25 wt% of a sodium chloride, sodium sulfate, magnesium hydroxide, polyethylene glycol (PEG), and glycerin; Regarding the environmentally friendly humidity indicator ink, characterized in that it comprises a pigment 0.1-5wt%, dispersant 0.1-3wt%, viscosity maintaining agent 0.1-5wt%,

When the present invention is classified macroscopically, a humidity indicator solution having a function of changing color due to a change in humidity in the air, and various colors, and to make ink for applying the humidity indicator solution by ink printing method (Ink printing method) It can be divided into a pigment, a dispersing agent, and a viscosity maintaining agent which are components to be included.

In addition, if the classification is classified microscopically according to the principle of action, the indicator changes the pH according to the reaction water and the color changes accordingly, and the moisture absorbed or released by the following moisturizer changes the pH of the indicator. Humidity indicator solution consisting of a buffer solution that prevents a slight pH change and induces a distinct color change of the indicator, a humidifier that functions to absorb or release moisture in the atmosphere, and an indicator according to the change of pH. In order to apply pigments to realize various colors with color change, dispersant for appropriately dispersing the pigments in other constituents, and to apply the humidity indication ink of the present invention to industrial ink printing method. It can be divided into a viscosity maintaining agent that functions to control the viscosity and the present invention in detail with reference to the drawings 1 to 2 below The people.

As mentioned above, the humidity indicator solution consists of an indicator, a buffer solution, and a humectant. The indicator consists of an alcohol solvent having 95 to 99.5 wt% of carbon atoms having 1 to 4 carbon atoms, and an indicator of 0.5 to 5 wt%. At this time, the indicator is a reagent that distinguishes the nature (acid, neutral, basic) of the substance by changing its color according to the pH of the substance. In the present invention, the pH of the buffer solution is changed by the moisture in the atmosphere The color of the indicator changes according to pH, and as a result, it is used as a component that changes the color of the entire humidity indicating ink. In addition, since the general indicator has its own discoloration range according to the type, in order to determine the pH of the substance using the discoloration of the indicator, the type of the indicator should also be changed according to the universal pH of the substance. Differentially, indicators with neutral and basic discoloration ranges are used. In other words, pure distilled water has a neutral pH of 7, but general moisture has a weak basicity of pH 8.3 or less, so that an effective color change can be recognized only by using an indicator having basic to neutral discoloration. Use indicators. In other words, the preferred indicator is an anthocyanin pH 2 to 13, cresol red pH 7.2 to 8.8, phenolphthalein pH 8.0 to 9.8 or a full range indicator pH 1 to 14 by using a discoloration range, such as reacting with water of average pH8.3 or less Effective color change can be recognized, and the indicator is determined by the ratio of acidic and basic forms so that the color changes and the concentration of the indicator is not related. 0.5 to 5 wt% is mixed with 95 to 99.5 wt% of the personal alcohol solvent.

In addition, a buffer solution is a mixture of an acid and its base. It is a solution that prevents the pH change when an acid or base is added. The pH of the buffer solution is determined by the following Henderson-Hasselbalch equation. You can get it.

[Chemical Formula]

^{HA ↔ A - + H + -} (1)

(HA: acid, A ^-: conjugate base ions, H ⁺ of the acid: acid ion)

when,

[Equation]

pH = pK _a ^{+ Log ([A -] /} [HA]) - (2)

That is, the buffer solution is a solution made by mixing an acid HA and a conjugate base A ^- in a reaction having the formula (1), Henderson-Hasselbalch, that the relationship between the molar concentration of ^a) equation (2)) in a buffer solution (pH is the acid dissociation constant (acid dissociation constant, K _a) of buffer solution) by the formula, an acid (HA), the molar concentration and its conjugate base (a of As can be seen, the preferred buffer pH range is determined by the following buffer capacity (β).

[Equation]

β = dC _ｂ / dpH =-dC _a / dpH-(3)

(β: buffer capacity, C _ｂ : number of moles of strong acid, dC _a : Forfeiture of strong base)

The above equation is a buffer capacity (β) indicating how much the solution prevents the pH change when a strong acid or strong base is added to the buffer solution, and in relation to the above equation (2), pH and C _ｂ or a mathematical expression expressing the ratio of pH to C _a and pH = pK _a ^{([HA] = [A -} ]) one can see that when the buffer capacity (β) is the maximum, at this time the buffer can be prevented most preferably to a pH change. In addition, in determining the pH of the buffer solution of the present invention whose pH is changed by moisture in the air in connection with the above, pK _a is as close as possible to the average pH of water. It is preferable to choose a buffer solution with a value pK _a Use a buffer solution with a pH of 7.3 to 9.3 in the range of ± 1. In addition, the buffer solution of the present invention, in addition to the above-mentioned indicators can be used as long as it is made of a general acid and base having a pH corresponding to the above range and is added at a composition ratio of 0.1 to 2wt% of the total humidity indicator solution.

In addition, the humectant is a composition for changing the pH of the present invention by absorbing or releasing moisture in the air, and uses a composition having excellent humidity control without reacting with the indicator and buffer solution. Therefore, the present invention uses sodium chloride, sodium sulfate, magnesium hydroxide, polyethylene glycol (PEG), and glycerin 0.1-25 wt% of one or more humectants to effectively absorb and release moisture in the air. At this time, the rate of absorbing and releasing moisture in the air varies depending on the type of the humectant and the composition ratio of the humectant, so that the color change humidity may be configured differently according to the use of the humectant by changing the type and composition ratio of the humectant. It is added in a composition ratio of 0.1-25 wt% of the humidity indicator solution in a range that does not impair the physical properties of.

In addition, the present invention includes the humidity indicator solution consisting of the indicator, the buffer solution, the humectant 80 ~ 99.9% by weight because the humidity indicator is less than 80wt% problem that the function of the humidity indicator falls.

In addition to the humidity indicator solution, the pigment is a composition for realizing the color of the present invention. However, the prior art is capable of color using only the humidity indicator solution. By including 0.1 ~ 5wt% of organic pigment or food coloring in the solution, it is possible to implement various colors as well as the color according to the pH of the indicator of humidity indicator, thus making the present invention more versatile in industrial use. Is a composition for uniformly dispersing the pigment in the humidity indicating solution, and is generally available as long as it has a function of surface-activated polarity and nonpolarity, and is preferably added in a composition ratio of 3 wt% of a water-soluble resin and a dispersant such as alkaline emulsion and gum arabic. It should not affect the function of other compositions.

In addition, a viscosity retaining agent is added as another composition for ink-inducing the humidity indicating solution, which is used only as an impregnation method because the viscosity of the conventional humidity indicating solution is inferior, so that it can be applied to various fields in industrial use. Problems with difficult side and process difficulty can be applied by ink printing method, economical and usability can be improved, and various colors can be realized to make it easy to recognize humidity in the atmosphere. . Viscosity retainers that function as described above may be used in general ink production, but it is preferable to use a viscosity retainer containing at least one of water-soluble cellulose and Xanthan Gum. Since the viscosity maintaining agent is a vegetable composition, it is harmless to the human body in the present invention, and thus, 0.1 to 5 wt% is added because it increases adhesiveness and viscosity and enables emulsification stability. The following describes the present invention in detail as a preferred embodiment of the present invention. The following examples do not limit the present invention and those skilled in the art can variously implement them within the scope of the present invention.

[Example]

1. Humidity indication ink manufacture

1-A. Humidity indicator solution

89 g of an indicator consisting of 97 g of ethyl alcohol solvent and 3 g of indicator CR (Aldrich, Cresol Red);

1 g of a buffer solution of pH 8 made of Tris hydrogen chloride and sodium hydroxide;

Prepare a humidity indicator solution containing 10 g of sodium chloride.

1-B. Humidity indicator ink preparation

96.8 g of the humidity indicator solution prepared above;

Humidity indicator ink is prepared by mixing 0.2 g of blue pigment (VIDHI Dyestuff Mfg., Ltd. Blue No. 1), 1 g of gum arabic, and 2 g of xanthan gum.

2. Application of humidity indicator ink

The humidity indicator ink prepared above is filled in a screen printer using an ink printing method and then printed on a paper card.

3. Results

In the dry state (relative humidity: 30%) as shown in Figs. 1 to 2, the humidity indicator ink, which was green, changed its color to violet in the wet state (relative humidity: 50%) to easily recognize the change in humidity. can do.

As in the above embodiment, the present invention does not contain any harmful components, and thus has no restrictions and harmful effects in manufacturing and use, and general basic solution (caustic) by using a buffer solution as a solution for controlling pH change of the humidity indicating solution. Soda solution), strong acid solution, pH is easily changed according to the amount of moisture absorbed or released by the humectant. As a result, it is effective to solve the problem of the prior art, which is difficult to expect a clear color change of the humidity indicator solution. Ink printing in the production facilities and products of modern industries such as electrical and electronics, home appliances, paper, food packaging, etc. by realizing the humidity indicator ink containing pigments, dispersants, and viscosity retaining agents in the humidity indicator solution composed of the Humidity management is possible by applying ink printing method, economical efficiency and usability are improved, and various colors are realized. It has the effect of easily recognizing the humidity in the air.

1 is a humidity indicator ink showing the color in a dry state according to an embodiment of the present invention.

Figure 2 is a humidity indicator ink showing the color in a humid state according to an embodiment of the present invention.

Claims (4)

70-99.8 wt% of an indicator consisting of 95 to 99.5 wt% of an alcohol solvent having 1 to 4 carbon atoms and 0.5 to 5 wt% of an indicator; 0.1-2 wt% of a buffer solution; 80 to 99.9 wt% of a humidity indicator solution containing 0.1 to 25 wt% of a sodium chloride, sodium sulfate, magnesium hydroxide, polyethylene glycol (PEG), and glycerin; Environmentally friendly humidity indicator ink characterized in that it comprises a pigment 0.1 ~ 5wt%, dispersant 0.1 ~ 3wt%, viscosity maintaining agent 0.1 ~ 5wt%. The method of claim 1, Eco-friendly humidity indicator ink, characterized in that the indicator is a basic indicator, one of anthocyanin, cresoled, phenolphthalein. The method of claim 1, Eco-friendly humidity indicator ink, characterized in that the buffer solution is a basic buffer solution in the range of pH7.3 ~ 9.3. The method of claim 1, Eco-friendly humidity indicator ink characterized in that the viscosity retaining agent comprises at least one of water-soluble cellulose and Xanthan Gum.

Images