JP4327567B2 - Erasable water-based ink composition for fiber assembly - Google Patents

Description

  The present invention relates to an erasable water-based ink composition for a fiber assembly, and more specifically, a fiber assembly such as a woven fabric or a nonwoven fabric can be marked. The present invention relates to an erasable water-based ink composition that can be easily washed out and erased by washing with water.

Conventionally, it is possible to mark a fiber assembly such as a woven fabric or a non-woven fabric. Further, after marking, if the fiber assembly is washed with water, the marking can be easily washed away and erased. Several water-based ink compositions are known. For example, an ink composition is known in which a pigment and a resin are kneaded to disperse a finely powdered water-insoluble colorant in water and a fixing agent or dispersant made of a water-soluble resin is dissolved therein. (See Patent Documents 1 and 2). However, in such an ink composition, the production of the colorant is complicated, and the erasability by washing with water is not sufficient.
Japanese Patent Laid-Open No. 7-3197 Japanese Patent Laid-Open No. 9-176539

  The present invention has been made in order to solve the above-described problems in conventional erasable water-based ink compositions for fiber assemblies, and can mark fiber assemblies such as woven fabrics and non-woven fabrics. An object of the present invention is to provide an erasable water-based ink composition that can be easily washed off and erased if the fiber assembly is washed with water after marking in this manner.

  According to the present invention, a fiber assembly comprising a pigment, an emulsion of an oily substance that is hardly volatile at normal temperature (25 ° C.), and a water-soluble resin having a film-forming ability at normal temperature (25 ° C.). A body erasable water-based ink composition is provided.

  According to the water erasable ink composition for a fiber assembly of the present invention, for example, a fiber assembly such as a fabric can be marked. Normally, this marking is not easily peeled off. By washing the fiber assembly with, for example, soap, the marking can be easily removed and erased from the fiber assembly as an oil stain.

  In the ink composition according to the present invention, a pigment is used as a colorant, and the pigment dispersion medium is water. The pigment used in the present invention is not particularly limited, and those conventionally used in ink compositions are appropriately used. Therefore, such a pigment may be an organic pigment or an inorganic pigment. Specific examples include, for example, carbon black, phthalocyanine pigments such as copper phthalocyanine blue, selenium, azo, quinacridone, anthraquinone, dioxane, indigo, thioindigo, perinone, perylene, indolenone, Examples thereof include, but are not limited to, azo-azomethine pigments. A fluorescent pigment is also used.

  According to the present invention, such a pigment is usually used in the range of 1 to 10% by weight in the ink composition. When the blending amount of the pigment is less than 1% by weight based on the ink composition, the marking concentration is too thin and lacks practicality. However, even if it exceeds 10% by weight, the marking does not become darker correspondingly, and on the other hand, the erasability is impaired. In particular, according to the present invention, the pigment is preferably blended in the range of 2 to 7% by weight in the ink composition.

  According to the present invention, such a pigment is blended in an ink composition as an aqueous pigment dispersion obtained by dispersing a water-soluble resin having a film-forming ability at room temperature (25 ° C.) as a dispersant in water. ing.

  Examples of such water-soluble resins include polyvinyl alcohol resins, styrene-acrylic resins, polyvinyl pyrrolidone, etc. Among them, polyvinyl alcohol resins are preferably used. In particular, according to the present invention, the water-soluble polyvinyl alcohol resin preferably has a saponification degree in the range of 70 to 85 mol%, and a 4% aqueous solution having a viscosity at 20 ° C. in the range of 2 to 30 mPa · s. Used.

  When the saponification degree of the polyvinyl alcohol resin is out of the above range, it is difficult to obtain a stable pigment aqueous dispersion. Further, when the viscosity at 20 ° C. of a 4% aqueous solution of polyvinyl alcohol resin exceeds 30 mPa · s, the dispersion stability of the pigment is good, but the marking property is inferior. On the other hand, when the viscosity is less than 2 mPa · s, In addition to being inferior in dispersion stability, the resulting ink composition is inferior in erasability, which is not preferable.

  According to the present invention, in the aqueous dispersion of the pigment using the water-soluble resin containing the polyvinyl alcohol resin as a dispersant, the water-soluble resin has a weight ratio of 1 to 5, preferably 1 to 3 with respect to the pigment. The range is 1 to 10% by weight, preferably 2 to 8% by weight, based on the ink composition.

  In the aqueous pigment dispersion, when the ratio of the water-soluble resin to the pigment is less than 1 by weight, the resulting ink composition is inferior in viscosity stability over time and thickens over time. Thus, if the viscosity of the ink composition is increased, the marking property becomes inferior, and eventually the erasability of the marking on the fiber assembly is also inferior. According to the present invention, an ink composition having excellent viscosity stability with time can be obtained by setting the ratio of the water-soluble resin to the pigment to 1 or more by weight ratio.

  However, when the weight ratio of the water-soluble resin to the pigment is greater than 5 or when the water-soluble resin is used in excess of 10% by weight based on the ink composition, the resulting ink composition Is too high in viscosity, inferior in marking properties, and erasability is not sufficient. On the other hand, when the amount of the water-soluble resin used is too small, the dispersion stability of the pigment is not sufficient in the obtained ink composition, and the obtained ink composition is inferior in erasability.

  In the present invention, the water-soluble resin is a pigment dispersant and at the same time has a film-forming ability at room temperature. Therefore, if marking on the fiber assembly using the ink composition according to the present invention, the water-soluble resin forms a film and covers and protects the marking on the fiber assembly. It is not removed from the fiber assembly when lightly rubbed.

  The water-based erasable ink composition according to the present invention is marked on a fiber assembly, and after drying, this marking is removed by washing, that is, as an erasing agent at room temperature (25 ° C.). And an oily substance which is hardly volatile is formulated as an O / W emulsion prepared using a surfactant as an emulsifier.

  As the oily substance, aliphatic carboxylic acid esters, higher hydrocarbons or higher alcohols are preferably used. The aliphatic carboxylic acid ester includes monobasic acid esters, dibasic acid diesters, dihydric alcohol mono- or diesters, trihydric alcohol mono-, di- or triesters, polyglycerin esters, and the like. In the present invention, such an aliphatic carboxylic acid ester is particularly preferably used as a release agent.

  According to the present invention, aliphatic carboxylic acid esters, particularly higher fatty acid alkyl esters or higher fatty acid glycerides among oily substances that are hardly volatile at room temperature (25 ° C.), for example, cetyl isooctanoate, isopropyl myristate, isopropyl palmitate , Isooctyl stearate, 2-hexyldecyl isostearate, diethyl sebacate, glyceryl tri (caprylate capric acid), and the like. Among these, in the present invention, isooctyl stearate, cetyl isooctanoate or glyceryl tri (caprylate caprate) is preferably used. Examples of higher hydrocarbons that are hardly volatile at room temperature (25 ° C.) include liquid paraffin, and examples of higher alcohols include hexyl alcohol, octyl alcohol, and dodecyl alcohol. These oily substances may be used alone or in combination of two or more.

  According to the present invention, the oily substance O / W emulsion can be prepared by a normal emulsification method using an appropriate surfactant as an emulsifier. Commercial products can also be used. Furthermore, if necessary, two or more emulsions of aliphatic carboxylic acid ester, higher hydrocarbon or higher alcohol can be blended in the ink composition.

  The ink composition according to the present invention contains, as a erasing agent, an oily substance that is hardly volatile at ordinary temperature (25 ° C.), usually in the range of 1 to 15% by weight in terms of its own weight. Is blended in the range of 2 to 13% by weight.

  When the ink composition according to the present invention is marked on the fiber assembly, such an oily substance forms a coating on the surface of the fiber assembly, and a pigment is deposited on the coating to form a marking. It is considered that the water-soluble resin forms a film on the marking formed as described above, and covers the marking.

  Accordingly, in the ink composition, when the oily substance is less than 1% by weight, the erasability of the marking is not sufficient. On the other hand, when the amount exceeds 15% by weight, the marking is poor and the erasability is poor. In addition, the marking property on the fiber assembly is inferior, and further, oil bleeding occurs when the fiber assembly is marked. The ink composition according to the present invention contains, for example, a wetting agent so that the ink composition does not dry at the pen tip when used in a marking pen. As this wetting agent, for example, water-soluble polyhydric alcohols such as glycerin, ethylene glycol, and propylene glycol are used in the range of 2 to 30% by weight based on the ink composition.

  Furthermore, in addition to the above, the ink composition according to the present invention may contain various surfactants as a surface tension adjusting agent, if necessary.

  The ink composition according to the present invention is preferably used by filling a marking pen. That is, according to the present invention, the ink composition is preferably for a marking pen. A marking pen is a writing instrument called a felt pen. It is equipped with a pen tip made of a plastic molding or the like at the tip of a cylindrical main body, and felt, fiber bundles, etc. are impregnated with ink in the main body. A writing instrument that enables marking on a fiber assembly by supplying ink from such an ink storage means to the pen tip by utilizing capillary action and a so-called core-type marking pen. The second is a non-core type or so-called free ink type marking pen in which ink is directly stored in a cylindrical main body and this ink is supplied to the pen tip.

  The ink composition according to the present invention is not particularly limited in its production method. For example, a pigment aqueous dispersion is prepared by dispersing a pigment in water using a water-soluble resin as a dispersant. Separately, as an erasing agent, an O / W emulsion of an oily substance was prepared. After that, water and an aqueous pigment dispersion were charged in a container together with a surfactant as necessary, and mixed with stirring. The ink composition according to the present invention can be obtained by adding a preservative, an antifungal agent, and the like to the emulsion, and if necessary, stirring and mixing.

  In addition to the above, the ink composition may contain any pH adjuster, preservative, antifungal agent, etc., which are usually blended in the aqueous ink composition, if necessary.

  As described above, the aqueous erasable ink composition for fiber assemblies according to the present invention has an oily substance that is hardly volatile at room temperature dispersed in water as an O / W emulsion as an erasing agent and a water-soluble pigment. The resin is dispersed in water using a water-soluble resin as a dispersant, and the water-soluble resin has a film-forming ability at room temperature.

  Therefore, it is considered that the marking formed on the fiber assembly, for example, the fabric using such an ink composition is easily removed, that is, erased from the fiber assembly for the following reason. That is, when a fiber assembly, for example, a fabric is marked using the ink composition according to the present invention, the oily substance in the ink composition covers the surface of the fiber assembly, and the pigment is deposited on the surface. In addition to forming the marking, the water-soluble resin is not miscible with the oily substance and coats and forms a film to protect the marking. Therefore, the marking on the fiber assembly is not easily peeled off under normal conditions.

  However, if such a fiber assembly is washed, the water-soluble resin dissolves in water and there is no protection against the marking. Furthermore, since soap or detergent is usually used in washing, Due to the action of the detergent, the pigment forming the marking is peeled off and separated from the fiber assembly together with an oily substance, so to speak as an oil stain, and thus the marking on the fiber assembly is easily removed, i.e. erased. is there. However, the present invention is not restricted by the reason that the marking is removed from the fiber assembly.

  EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to these examples. In the following Examples and Comparative Examples, the ratio of each component in the ink composition is indicated by weight%, and the balance is water.

Example 1
Pigment dispersion Black pigment dispersion ¹⁾ 40.0
Emulsifier of cetyl isooctanoate (oily substance 5
0%) 20.0
Wetting agent Glycerin 10.0
Preservative Proxel XL-2 (Avisia Co., Ltd.) 0.5

Example 2
Pigment dispersion Red pigment dispersion ²⁾ 40.0
Eraser Diethyl sebacate emulsion (oil 50
%) 15.0
Wetting agent Glycerin 10.0
Preservative Proxel XL-2 (Avisia Co., Ltd.) 0.5

Example 3
Pigment dispersion Blue pigment dispersion ³⁾ 40.0
Eliminating agent for tri (caprylic acid capric acid) glyceryl
John (50% oily substance) 10.0
Wetting agent Propylene glycol 15.0
Preservative Proxel XL-2 (Avisia Co., Ltd.) 0.5

Example 4
Pigment dispersion Green pigment dispersion ⁴⁾ 40.0
Eraser White mineral oil emulsion (oily substance
50%) 20.0
Wetting agent Propylene glycol 15.0
Preservative Proxel XL-2 (Avisia Co., Ltd.) 0.5

Example 5
Pigment dispersion Black pigment dispersion ⁵⁾ 40.0
Emulsifier of cetyl isooctanoate (oily substance 5
0%) 20.0
Wetting agent Glycerin 10.0
Preservative Proxel XL-2 (Avisia Co., Ltd.) 0.5

Comparative Example 1
Pigment dispersion Blue pigment dispersion ³⁾ 40.0
Wetting agent Propylene glycol 15.0
Preservative Proxel XL-2 (Avisia Co., Ltd.) 0.5

Comparative Example 2
Pigment dispersion Red pigment dispersion ⁶⁾ 40.0
Wetting agent Glycerin 10.0
Preservative Proxel XL-2 (Avisia Co., Ltd.) 0.5

(Note 1) Pigment dispersion 1) Black pigment dispersion 8% by weight of carbon black (Special Black 100) pigment and polyvinyl alcohol resin (Poval PVA-403 manufactured by Kuraray Co., Ltd., saponification degree 78.5-81.5) A water-based pigment dispersion comprising 12% by weight of a mol%, 4% aqueous solution at 20 ° C. and a viscosity of 2.8 to 3.3 mPa · s).

2) Red pigment dispersion 8% by weight of Novo Palm Red GLF pigment and polyvinyl alcohol resin (Poval L-9-78 manufactured by Kuraray Co., Ltd., saponification degree 76.5-79.0 mol%, 4% aqueous solution at 20 ° C An aqueous pigment dispersion comprising 12 wt% of a viscosity of 6.0 to 6.7 mPa · s).

3) Blue pigment dispersion 8% by weight of chromoftal blue A3RJ pigment and polyvinyl alcohol resin (Poval PVA405 manufactured by Kuraray Co., Ltd., saponification degree: 80.0 to 83.0 mol%, 4% aqueous solution viscosity at 20 ° C. 5 to 5.2 mPa · s) and 15% by weight of an aqueous pigment dispersion.

4) Green pigment dispersion 10% by weight of Lionol Green 6YK pigment and polyvinyl alcohol resin (Nippon Synthetic Chemical Co., Ltd. Gohsenol KM-11, saponification degree 76.7-79.3 mol%, 20% of 4% aqueous solution) An aqueous pigment dispersion having a viscosity of 11.7 to 14.3 mPa · s) at 10 ° C.

5) Black pigment dispersion An aqueous pigment dispersion comprising 10% by weight of Monarch 800 pigment and 15% by weight of styrene-acrylic resin (John Crill 62 manufactured by Johnson Polymer, solid content: 34% by weight).

6) Red pigment dispersion An aqueous pigment dispersion comprising 8% by weight of Shimler Fast Red 4127 pigment and 15% by weight of styrene-acrylic resin (John Crill 63 manufactured by Johnson Polymer, solid content of 30% by weight).

  The above ink composition was filled into a core-type marking pen, and a continuous circle was marked on a JIS union cloth made of various materials shown in Table 1, and then allowed to stand at room temperature for 24 hours and dried. The cloth was divided into two parts, one was used as a blank, and the other was washed by hand using a solid soap and dried, and then the erasability of the marking was evaluated. ◎ when there is no marking left, ◯ when a part of the marking is slightly left, △ when the color or shape of the marking is clearly left, △ when no marking is removed did. The results are shown in Table 1.

  As is apparent from the results shown in Table 1, the ink compositions of the present invention according to Examples 1 to 4 use a polyvinyl alcohol resin as a water-soluble resin together with an emulsion of oily substances, and are woven fabrics of almost all materials. The top marking has been (almost) completely removed by washing. The ink composition of the present invention according to Example 5 uses a styrene-acrylic resin as a water-soluble resin together with an emulsion of an oily substance, and the markings are almost completely removed by washing on unwoven fabrics of many materials. .

On the other hand, according to the ink composition of Comparative Example 1, polyvinyl alcohol resin is used as the water-soluble resin, but it does not contain oily substances. Remains clearly. According to the ink composition of Comparative Example 2, the styrene-acrylic resin is used as the water-soluble resin, but since it does not contain an oily substance, the marking is not removed at all even when washing is performed on the unwoven fabric of most materials. .

Claims (4)

And 1 to 10 wt% pigment, the oil 1-15 wt% of the emulsion is a low volatility at room temperature (25 ° C.) as a scavenger, room temperature as the water-soluble resin having a film forming ability at (25 ° C.) Polyvinyl alcohol resin having a saponification degree in the range of 70 to 85 mol%, a viscosity of 4% aqueous solution in the range of 2 to 30 mPa · s at 20 ° C., and 2 to 30 weights of water-soluble polyhydric alcohol as a wetting agent % Erasable water-based marking pen ink composition for fiber assembly , wherein the pigment comprises the polyvinyl alcohol resin in a weight ratio of 1 to 5 with respect to the pigment, and the ink composition. Based on the above, it is blended as a pigment water dispersion formed by dispersing in water using it as a dispersant in the range of 1 to 10% by weight. Ink composition. And 1 to 10 wt% pigment, the oil 1-15 wt% of the emulsion is a low volatility at room temperature (25 ° C.) as a scavenger, room temperature as the water-soluble resin having a film forming ability at (25 ° C.) styrene - acrylic resin, a fiber aggregate-body Clear aqueous marking pen ink composition comprising a water-soluble polyhydric alcohols having 2 to 30 wt% of a wetting agent, in the preparation, the pigment is the styrene - acrylic resin An erasable water-based marking pen ink composition for a fiber assembly, wherein the composition is formulated as a pigment aqueous dispersion obtained by dispersing the pigment in water using a dispersant . The ink composition according to claim 1 or 2 , wherein the oily substance is at least one selected from aliphatic carboxylic acid esters, higher hydrocarbons and higher alcohols. The ink composition according to claim 1 or 2, wherein the water-soluble polyhydric alcohol as the wetting agent is glycerin, ethylene glycol or propylene glycol.