KR20050030647A - Ink composition containing optically variable hybrid pigments - Google Patents

Abstract

Provided is an optically variable ink composition containing an optically variable hybrid pigment whose color depends on the angle of view which is excellent in economical efficiency and is improved in optically variable effect. The optically variable ink composition contains an optically variable hybrid pigment which comprises 10-90 wt% of a first optically variable pigment where a metal-phthalocyanine colored layer is formed by chemical coating on pearlescent mica; and 10-90 wt% of a second optically variable pigment comprising a multilayered thin film comprising a metal absorbing body, a dielectric substance and a metal reflecting material formed by physical deposition. Preferably the first optically variable pigment is obtained by forming a metal-phthalocyanine colored layer on the metal oxide layer coated on a natural mica or a synthetic mica, shows a gold color, red, blue and green in turn repeatedly according to the increase of optical thickness as a side color and shows blue, blue-green or green as a front color. Preferably the color of the second optically variable pigment is changed according to the thickness of a dielectric substance.

Description

Ink composition containing an optically variable composite pigment {Ink Composition Containing Optically Variable Hybrid Pigments}

The present invention relates to an ink composition containing a composite pigment consisting of two types of optically variable pigments whose color varies depending on the angle observed. More specifically, the present invention provides a first light-variable pigment and a metal absorber, a dielectric and a metal reflector in which a metal-phthalocyanine colored layer is formed on a pearl mica by a chemical coating method, and a second thin film formed by physical vapor deposition. By using a composite pigment composed of a light variable pigment, the present invention relates to an ink composition which not only exhibits an improved light variable effect as compared with the case of using the above two types of pigments alone, but also can sustain light variable performance for a long time.

In the present invention, the "optically variable effect" means that the color appears differently depending on the angle viewed by a material. In addition, although expressed as a two-color effect, a color shifting effect, etc., in the present invention, collectively referred to as "light variable effect", a pigment having such a light variable effect "light variable pigment" It is written as. In addition, the light variable effect that occurs when a light variable pigment or an ink is prepared and transferred or printed on a proper medium needs to define terms according to the angle to be observed.

As a general method of expressing a color, the color of a material viewed from the front may be referred to as the front color, and the color of the material slightly tilted may be expressed as a side color. When placed horizontally, the color seen from the front (an angle of 90 ° or vertical) when viewed from the side (an angle of about 45 °) is expressed as "front color", and the light is reflected (a comprehensive angle near 135 °). The color that appears is expressed as "side color". In this case, the viewing angles of the front color and side color are interpreted more widely.

In general, the light variable pigment is mainly composed of multiple layers, and exhibits a light variable effect by refraction, reflection, transmission, or the like of light. The most representative example of such an effect is a pearlescent pigment (pearlescent pigment). Generally, the pearl pigment is made of fine mica, and the surface of the particle is coated with a metal oxide such as titanium dioxide to a certain thickness, and when viewed from the front (angle around 90 °), the pigment color appears as off-white to silver-white. When viewed from the side (angles around 45 ° and 135 °), distinctive interference colors appear as the coating thickness increases. In the following, mica (including natural mica and synthetic mica) is coated with a metal oxide to have a pearly interference color effect.

Such a pearl pigment is generally a multilayer form of a thin film composed of a partially or completely reflective material and a low refractive index material, and consists of a metal layer, a metal oxide layer, an organic colorant layer, and the like, and is manufactured by a method such as deposition, coating, or orientation. The front and side colors of the optically variable pigments prepared as described above are different in hue, saturation, and brightness, and the color change is related to the material of the thin film layer, the number of layers, the thickness of the layer, and the manufacturing. It depends on the method.

In this regard, the light-variable pigments can be divided into chemical coating (first type) and physical vapor deposition (second type) according to the manufacturing method, and the first type and the second type of Light variable pigments have different light variable effects due to different manufacturing methods, different physicochemical properties of pigments, and significant differences in manufacturing cost.

As an example of the first type pigments, a metal oxide is coated on the surface of natural mica or synthetic mica to electrolessly plate a metal on the surface of the mica of pearl effect having a side color by interference of light, and the metal and the organic compound are coated. There is a form in which the front color appears by reacting and coloring.

In this regard, Korean Patent Publication No. 195-23683 filed by the applicant of the present invention coats metal oxide on the surface, coats the metal again on the mica on which the interference color layer is formed, and reacts the phthalonitrile on the coated metal film. To disclose a dichroic mica having a reflective color layer by metal-phthalocyanine coloring, which is considered as a reference of the present invention.

In addition, Korean Application No. 2002-87181, filed by the present applicant, discloses a method for producing a phthalocyanine-coated mica in which a metal layer is formed on the surface of the mica and the metal and tetracyanobenzene are combined to form a colored layer. This is considered as a reference of the present invention.

In the above-described prior art (Korean Patent Publication No. 1995-23683 and Domestic Application No. 2002-87181), since metal-phthalocyanine pigment is formed on the surface of mica, chemical resistance against acid and alkali, various It is excellent in solvent resistance to solvents and light resistance to various lights. In addition, since the raw material is cheap and the manufacturing method is relatively simple, the production cost is low. However, there is a disadvantage that the light variable effect is insufficient. In addition, since the metal-phthalocyanine is thinly formed, it has a certain degree of transparency, so that the concentration of the pigment may be high when the ink is manufactured and used, so that the intended optical variable effect can be exhibited. It may be an advantage or disadvantage depending on various factors such as a printing pattern.

An example of the preparation of the pigment of the second type is disclosed in U.S. Pat.Nos. 4,434,010, 4,779,898, 4,838,648, 4,930,866, 5,135,812, 5,171,363, 5,214,530, and the like. It is considered a reference for. In the above-described pigment, the metal layer and the dielectric layer, which is a metal oxide having a low refractive index, are formed in a multilayered structure so that the light appears by complex refraction and reflection in the interior, and thus the front and side colors are varied. In addition, it is excellent in solvent resistance to solvents, light resistance to various kinds of light, and the light variable effect among known light variable pigments. However, since the metals and metal dielectrics constituting the pigment are made of nano-deposited thin film deposition layers, chemical resistance to acids and alkalis is significantly low, and not only expensive raw materials are used but also the manufacturing method must be very complicated and sophisticated. The production cost is very high. In particular, because it has a metal reflective layer, it is opaque, and thus the light variable effect is good even when the concentration of the pigment is low during ink production and use, but the color is often changed according to various factors such as printing products, colors, and printing patterns requiring the light variable effect. It is necessary to modify and use.

As exemplified above, the first type of pigment in which the metal-phthalocyanate colored layer is formed on the pearl mica by chemical coating and the second layer of the dielectric layer of the low refractive index metal oxide layer and the metal layer by physical deposition When the pigment is used alone, it is difficult to satisfy all of the light variable effect, the persistence of the light variable effect, economical efficiency, and the like.

The present inventors have studied to solve the above-mentioned problems of the prior art. As a result, the first type of pigment having a metal-phthalocyanate colored layer by chemical coating on pearl mica and a metal absorber, dielectric and metal by physical vapor deposition In the case of using the composite pigment composed of the second type of pigment consisting of a multilayer thin film of the reflector, not only the problem caused when the two types of pigments are used alone can be solved, but also various physical properties of the optically variable ink composition containing the same. You can find that you can satisfy at the same time.

Accordingly, an object of the present invention is to provide a first optically variable pigment having a metal-phthalocyanate colored layer on a pearl mica by a chemical coating method and a second optically variable layer consisting of a multilayer thin film of a metal absorber, a dielectric and a metal reflector by physical vapor deposition. It is to provide a light variable ink composition that can solve the problems caused when using a pigment alone.

It is another object of the present invention to provide a light variable ink composition which is excellent in light variable performance and light variable persistence and can significantly reduce production costs.

The optically variable ink composition of the present invention for achieving the above object is composed of a first optically variable pigment in which a metal-phthalocyanine colored layer is formed by chemical coating on pearl mica and a multilayer thin film of a metal absorber, a dielectric and a metal reflector by physical vapor deposition. It is characterized by containing the light-variable composite pigment which consists of a 2nd light-variable pigment.

Hereinafter, the configuration of the present invention will be described in detail with reference to the accompanying drawings.

In the present invention, since the color representation has an objective aspect and a subjective aspect every week, it will be based on the following documents. Griffiths, "Color and Constitution of Organic Molecules" Academic Press London, 1976]

That is, as a concept of color, generally, a substance absorbing about 350 to 750 nm visible light is collectively called a pigment, and the absorption spectrum of the pigment is measured by dispersing it in a solution or a solid, and generally recording a wide absorption band. The characteristics of the spectrum are determined by the absorption maximum wavelength (λ max) and the molar absorption coefficient (ε).

The relationship between the absorbed light of the dye representing the color and the color (color) is expressed as a diagonal image of the color circle. That is, when a pigment absorbs the purple light of 400-435 nm, its color (yellow color) is yellowish green, and when it absorbs the blue light of 435-480 nm, the color of the pigment is yellow (gold), 480-490. Absorption of cyan light of ㎚, the color of the pigment absorbs orange, 490-500 nm of blue-green light. The color of the dye absorbs red, 500-560 nm of green light. Absorbs 560-580 nm yellow-green light, the color of the pigment is purple, 580-595 nm yellow light. The color of the pigment is blue, and 595-605 nm orange light. When the color of the dye absorbs green blue and red light of 605 to 700 nm, the color of the dye is expressed in blue green.

In the present invention, the first light-variable pigment, which is one component of the composite pigment, is a metal by chemical coating on pearl mica, as exemplified in Korean Patent Publication No. 195-23683 and Korean Application No. 2002-87181. It is a pigment form which has a phthalocyanine colored layer formed. An exemplary aspect of the method for producing the light variable pigment is based on pearl mica which shows the respective side color as thickness increases by attaching titanium dioxide, zirconium dioxide, chromium oxide or bismuth oxide as colloidal forms as metal oxides as thin films. Use as a substance. After coating the metal by the electroless plating method so that the metal layer is formed on the surface of the metal mica coated pearl mica, the metal layer is phthalocyanated by reacting the plated metal layer with, for example, phthalonitrile or tetracyanobenzene. It is a method of manufacturing. In other words, the metal oxide is coated on the surface to coat the metal on the pearl mica in which the side color is formed, and the phthalocyanine-based compound is reacted with the coated metal film to have the front color by metal-phthalocyanine coloring.

Since the color of the first light-variable pigment is a metal-phthalocyanine is formed as a thin film on the surface of the pearl mica, the side color of the mica does not change much, and the front color of the colorless pearl mica is phthalocyanine-based pigment to form blue to green. appear. This front color is a kind of electroless plated metal, for example, phthalonitrile, tetracy, to form a metal-phthalocyanine complex with copper, nickel, cobalt and nickel-cobalt-phosphorus alloys, nickel-copper-phosphorus alloys, and the like. The color varies depending on the anobenzene, but generally falls in the range of blue, blue green or green. More specifically, there are blue / gold, blue / purple, blue / green of copper and phthalonitrile-based, and there are blue green / gold, blue green / purple, blue green / blue, etc. Varies (Front / Side Color) In the case of the side color, the metal oxide is coated, and the optical thickness is about 210 nm, and the color is gold, red at about 250 nm, blue at about 310 nm, and green at about 360 nm. Has the property of appearing again and again.

As described above, the light-variable pigment has a metal-phthalocyanine complex formed on the surface of the pearl mica in which the metal oxide layer is formed on the natural mica or the synthetic mica. Representative compositions of natural mica usable above are M ₂ O ₃ Al ₂ O _{3 6} SiO _{2 2} H ₂ O (M is, for example, iron or magnesium), and titanium dioxide (TiO ₂ ) as the metal oxide. The back is coated to form pearl mica. The particle size is preferably about 3 to 60 µm, the particle thickness is about 0.1 to 2.0 µm, the refractive index is about 1.50 to 1.60, and the specific surface area is about 1 to 8 m 2 / g. The first light-variable pigment has the disadvantage that the manufacturing cost of the product is very low, and excellent in chemical resistance, light resistance, solvent resistance, etc. that the pigment should have basically, but the width of the color change of the light variable is relatively small. .

In the present invention, the second optically variable pigment as one component of the composite pigment is exemplified in US Patent Nos. 4,434,010, 4,779,898, 4,838,648, 4,930,866, 5,135,812, 5,171,363, 5,214,530, and the like. As can be seen, the physical vapor deposition takes the form of a multilayer thin film of a metal absorber, a dielectric and a metal reflector. As such a pigment, for example, a symmetrical laminated structure in which a reflector layer is used as a core layer, dielectric layers are formed on both sides of the reflector, and absorber layers are formed on both sides of the dielectric layer can be used.

Exemplary methods of preparing the second light-variable pigment include vacuum evaporation of an absorber (e.g., chromium), a dielectric (e.g., magnesium fluoride), and a reflector (e.g., aluminum) on a plastic substrate. Alternatively, the multilayer thin film layer is separated from the plastic substrate by pulverization and laminated in a multilayer structure in the same order as the absorber / dielectric / reflector / dielectric / absorber, and then pulverized for each particle. In particular, in the case of the second light-variable pigment exemplified above, the color may be adjusted according to the change in the thickness of the absorber / dielectric / reflector / dielectric / absorber of the multilayer structure, and is typically 50 Hz / 4,000 Hz / 900 Hz / 4,000 Hz / 50 Hz. . At this time, the color mainly changes according to the thickness change of the dielectric layer, and typical colors include gold / green, green / purple, green / blue, purple / green, etc. (front / side color), and a specific pigment or dye Mixing can change the color change to some extent.

In addition, the particle size of the second light-variable pigment can be adjusted according to the intended use, and typically has a size of about 5 to 30 μm and a particle thickness of about 1 μm for a printing ink.

The second light-variable pigment has a wide range of color change of the light-variable and opaque to reduce the pigment content required when manufacturing the ink, and excellent light resistance, solvent resistance and the like. On the other hand, manufacturing and production costs are very expensive due to the vacuum deposition process of five or more layers, fine adjustment of the deposition thickness, separation and fine particle formation of the deposited thin film, and chemically react with an acid and / or an alkali when preparing ink to vary the light. The effect is drastically deteriorated, and the color is sensitively changed according to the angle change, and thus the recognition of the color may be small.

The first light variable pigment and the second light variable pigment described above commonly exhibit metallic luster, have a flaky shape in the form of meat scales, and need to maintain a range of particle sizes. In general, the size of the pigment particles for exhibiting the light variable effect is about 1 to 60 µm, but is preferably about 3 to 30 µm for application to a printing ink. In particular, when the particles of the light-variable pigment are about 3 μm or less, the light-variable effect disappears. This is because the rate of reflection decreases.

In the first light variable pigment and the second light variable pigment, the change width of the light variable color and the perceived width felt by a person are, for example, as follows.

When the first light-variable pigment is blue / purple, the recognition color may be high because blue color is seen from the front and purple color is seen from most side angles. have.

When the second light-variable pigment is gold / green, the printed matter is gold when viewed from the front, but the recognition of the color is low because the mixed color of gold and green changes little by little as the side angle is changed. That is, the overall light variable effect is good, but the partial light variable effect is worse than that of the first light variable pigment.

As such, the first light variable pigment and the second light variable pigment used in the present invention have a considerable difference from the light variable effect and the color difference value which are detected when visual observation, because the pigment production method is different and the principle is different. In view of the light variable effect, the second light variable pigment is more preferable.

On the other hand, although there is no rational colorimeter to measure the light variable effect, it can be compared by a numerical value or chromaticity diagram measured using an angle conversion color difference meter that measures the color while changing the angle. However, the numerical value or chromaticity measured in this way cannot be seen as an absolute light variable effect.

In the present invention, the above-mentioned first light variable pigment and the second light variable pigment are suitably mixed and used according to the characteristics of the ink to be prepared. In this regard, the mixing ratio is preferably in the range of about 10/90 to 90/10 by weight, more preferably in the range of about 30/70 to 70/30, so that the respective pigments are mixed. It is possible to manufacture an ink in which the light-variable color that is contained varies. If any one of the two types of pigments is contained in an excessively large or small proportion, problems may occur when using either pigment alone as described above. In this case, the first light variable pigment and the second light variable pigment may be suitably used in combination of two or more pigments belonging to each category in order to achieve a desired color.

The light variable ink composition provided according to the present invention is observed differently in front color and side color, and has excellent metallic luster, light resistance, durability, and the like, so that it can be variously used for automobile paint, nail polish, plastic case, printing ink, paint, and toys. Can be applied. However, since the pigment is relatively expensive and limitedly produced and used, it is particularly effective to use it as a visual authenticity ink or anti-counterfeiting ink of securities and security printing products. Applying such a light variable ink composition to banknotes, securities, etc., it is possible to easily identify the authenticity when visual observation, and in particular, it is difficult to reproduce the light variable effect when forging a printed product with a sophisticated copier or computer output. It is suitable for the manufacture of anti-counterfeiting ink. At this time, considering the transfer characteristics of the ink, because the particles of the complex pigment is relatively large, the printing method is intaglio printing, screen printing, gravure printing is effective, it can be prepared and used as the ink having the physical properties suitable for the printing method. In particular, the light variable effect is excellent in the effect of color change only when the particles of the pigment in the ink are arranged in parallel to the printing medium after the printing medium ink such as paper, plastic, or the like is transferred.

In view of the foregoing, the light variable ink provided according to the present invention is added in an appropriate amount so as to meet the required properties of the ink to be prepared as described above. In this regard, intaglio inks generally have a high solid content and high viscosity, whereas screen inks, gravure inks and flexo inks have a low solids content due to their low solid content and high solvent content. For example, intaglio printing inks have a very high pigment content of 50% by weight or more, and screen printing and gravure printing inks have a low content of pigments of 50% by weight or less. Solvent-rich ink forms are good for light variable effects. As such, the components of the ink other than the composite pigment are well known in the art, and are not particularly limited in the present invention.

The ink composition of this invention can use resin, an oil, a solvent, etc. as a vehicle which is an approximately main material, and contains the light variable composite pigment which is the above-mentioned color material. In addition, at least one auxiliary material selected from a viscous agent, a desiccant, a wax, a diluent, a surfactant, a plasticizer, and the like may be added for workability, dryness, printability, and the like. However, the use of an additive having a chemical reaction with the surface of the pigment and the component having a color number to reduce the light variable effect should be excluded. In order to further improve physical properties such as the light variability effect and glossiness of the light variable ink, a glossy material may be selectively added as a filler. Such fillers are selected from at least one of pearl pigments, gold powder, silver powder, copper powder, transparent silica and the like.

The present invention can be more clearly understood by the following examples, which are only intended to illustrate the present invention and are not intended to limit the scope of the invention.

Comparative Example 1

Preparation and printing of photo variable inks

The light variable ink prepared in Comparative Example 1 is a solvent evaporative screen ink, and as a resin component, about 20% by weight of polyvinyl chloride resin (trade name: Solvin A, molecular weight 50,000) and urethane-modified alkyd resin (molecular weight: 24,000), as a solvent Alcohol-based ethers (ethoxypropionic acid ethyl ester and dipropylene glycol monoethyl ether), aliphatic petroleum solvents (boiling point: 280-320 DEG C) were blended in about 60% by weight and pigments in about 20% by weight. The pigments used were the first light variable pigment and the second light variable pigment, respectively. In addition, a small amount of fumed silica (SiO ₂ ; Arosil 300) having a filler property and a small amount of dioctylphthalate having a plasticizer property were added as an auxiliary agent for printability of the ink.

The first light-variable pigments were blue or blue green / gold, blue or blue green / purple, and blue or blue green / green, respectively, for convenience, hereinafter "# 1 Blue / Gold", "# 1Blue / Violet", and "# 1Blue / Green ". In addition, the second optically variable pigments were gold / green, green / purple, and purple / green by color, respectively, and are referred to as "# 2Gold / Green", "# 2Green / Violet", and "# 2Violet / Green" for convenience. It was.

The ink prepared as described above was printed by the silk screen method. At this time, the screen used was 150 mesh, the thickness of the screen was about 30㎛. The thickness of the ink coating film after drying was about 15 micrometers.

Measurement of light variable effects

The light variable effect was evaluated using a multi-angle spectrophotometer (trade name MA68 II, manufactured by X-rite), and various angles (15 ° / 25 ° / 45 ° / 75 ° / 110 based on the reflection angle of light) were evaluated. Measured at °.

By using the CIE L ^* a ^* b ^* colorimetric chromaticity diagram obtained by using the angle conversion color difference meter, the light variable effect can be quantified and displayed. The CIE L ^* a ^* b ^* colorimetric chromaticity diagram is a display method using a color coordinate space by developing the XYZ color to study the difference of the color difference between two colors according to the difference of the senses. The color space and color method, in which the difference in color value between two colors and the difference in sensation when looking at color, are easily matched, because of the low correlation with. In general, in CIE L ^* a ^* b ^* , L ^* represents brightness, a ^* and b ^* represent chromaticity coordinates, + a ^* for red direction, -a ^* for green direction, + b ^* for yellow direction,- b ^* indicates the blue direction, and chromaticity increases outward from the center of the chromaticity diagram. L ^* a ^* b ^* may be defined as in Equation 1 below.

In the above, X, Y and Z are three stimulus values of the color used in the XYZ color system, and X ₀ , Y ₀ and Z ₀ are three stimulus values of the illumination light source.

Test results for the light variable effect are shown in Tables 1 and 2 below, and the CIE L ^* a ^* b ^* colorimetric chromaticity diagrams for the results are shown in FIGS. 1 and 2.

Measuring angle L ^* a ^* b ^* # 1Blue / Gold # 1Blue / Violet # 1Blue / Green 15 ° L ^* 103.62 75.79 102.90 a ^* -2.54 23.84 -26.00 b ^* 37.74 -13.61 18.29 25 ° L ^* 88.28 66.89 89.73 a ^* -4.19 18.52 -22.64 b ^* 27.80 -13.45 16.64 45 ° L ^* 64.13 53.17 66.12 a ^* -7.80 6.20 -15.49 b ^* 7.66 -11.46 9.46 75 ° L ^* 51.37 45.32 50.42 a ^* -11.19 -4.92 -9.92 b ^* -4.54 -8.79 1.58 110 ° L ^* 48.93 44.26 48.24 a ^* -12.60 -8.68 -9.81 b ^* -6.48 -8.34 -1.17

Measuring angle L ^* a ^* b ^* # 2Gold / Green # 2Green / Violet # 2Violet / Green 15 ° L ^* 109.83 82.27 95.63 a ^* -11.11 -1.34 61.32 b ^* 71.72 -36.25 4.06 25 ° L ^* 83.97 69.43 73.84 a ^* 3.48 -23.53 55.41 b ^* 48.77 -18.39 -12.23 45 ° L ^* 48.75 46.35 45.24 a ^* 11.20 -29.77 28.11 b ^* 14.80 4.70 -17.06 75 ° L ^* 32.80 28.51 33.81 a ^* 3.41 -12.83 7.74 b ^* 2.11 5.57 -5.88 110 ° L ^* 29.20 22.34 30.51 a ^* -0.44 -4.84 3.00 b ^* -0.76 2.48 -1.55

Example 1

# 1 Blue / Green as the first light variable pigment and # 2 Gold / Green as the second light variable pigment at various mixing ratios (0/100, 30/70, 50/50, 70/30 and 100/0 by weight). Except having prepared the ink by mixing, it carried out in the same manner as in Comparative Example 1 to evaluate the light variable effect.

Test results for the light variable effect are shown in Table 3 below, and the CIE L ^* a ^* b ^* colorimetric chromaticity diagrams for the results are shown in FIG. 3.

Measuring angle L ^* a ^* b ^* (# 1Blue / Green) / (# 2Gold / Green) 0/100 30/70 50/50 70/30 100/0 15 ° L ^* 109.83 102.42 101.39 92.82 86.72 a ^* -11.11 -15.67 -9.30 -12.60 -11.01 b ^* 71.72 55.58 46.25 26.12 6.52 25 ° L ^* 83.97 82.49 81.35 78.17 76.45 a ^* 3.48 -2.84 -1.33 -7.64 -12.07 b ^* 48.77 40.00 27.18 14.45 -0.18 45 ° L ^* 48.75 51.58 54.80 56.06 59.52 a ^* 11.20 5.54 -0.36 -6.78 -14.70 b ^* 14.80 10.16 1.26 -5.64 -13.56 75 ° L ^* 32.80 36.26 42.70 44.46 48.86 a ^* 3.41 -0.96 -6.18 -11.14 -17.59 b ^* 2.11 -2.84 -9.11 -15.18 -22.21 110 ° L ^* 29.20 32.00 38.91 40.78 45.38 a ^* -0.44 -4.83 -9.36 -13.19 -19.40 b ^* -0.76 -6.17 -11.80 -17.79 -24.56

Example 2

Except that the ink was prepared by fixing the mixing ratio of the first light variable pigment and the second light variable pigment at 50:50 by weight, and combining various types of the first light variable pigment and the second light variable pigment. It carried out similarly to the comparative example 1, and evaluated the optical variable effect.

Test results for the light variable effect are shown in Table 4 below, and the CIE L ^* a ^* b ^* colorimetric chromaticity diagrams for the results are shown in FIG. 4.

Measuring angle L ^* a ^* b ^* (# 1Blue / Violet) / (# 2Viloet / Green) (# 1Blue / Violet) / (# 2Green / Viloet) (# 1Blue / Gold) / (# 2Gold / Green) 15 ° L ^* 99.39 89.82 115.57 a ^* 49.70 9.68 -9.34 b ^* -16.55 -41.94 62.05 25 ° L ^* 73.87 71.29 85.09 a ^* 35.12 -3.47 -1.08 b ^* -20.52 -24.41 35.56 45 ° L ^* 50.96 52.54 53.80 a ^* 9.34 -8.33 0.55 b ^* -12.02 -7.16 5.91 75 ° L ^* 43.73 45.01 42.42 a ^* -1.08 -7.72 -3.46 b ^* -5.45 -3.24 -3.88 110 ° L ^* 42.83 42.85 40.07 a ^* -4.13 -6.64 -5.68 b ^* -5.35 -4.40 -6.42

Comparative Example 2

For printed specimens obtained by printing in the same manner as in Comparative Example 1, except that ink was prepared using # 1 Blue / Green as the first light variable pigment and # 2 Gold / Green as the second light variable pigment alone. Chemical resistance was tested by the method of.

Chemical resistance test

The printed specimen of the light variable ink composition was cut to a size of 2 × 2 cm 2 to measure chemical resistance test and thus light variable properties. The acid resistance test was performed by immersion at 25 ° C. for 30 minutes using 5% by weight aqueous hydrochloric acid solution, alkali test by caustic soda 2% by weight aqueous solution and 100% by weight acetone.

Test results for the light variable effect after the chemical resistance treatment are shown in Table 5, and the CIE L ^* a ^* b ^* colorimetric chromaticity diagrams for the results are shown in FIGS. 5 and 6.

Measuring angle L ^* a ^* b ^* # 1Blue / Green # 2Gold / Green NaOH 2% HCl 5% Acetone NaOH 2% HCl 5% Acetone 15 ° L ^* 88.57 87.41 85.20 78.12 79.14 118.27 a ^* -9.71 -9.84 -10.18 -3.63 -7.17 -12.29 b ^* 11.63 7.80 7.27 11.08 4.85 80.38 25 ° L ^* 77.85 76.50 74.36 63.10 64.83 91.32 a ^* -10.58 -10.94 -11.77 2.05 -1.71 3.82 b ^* 4.26 0.00 -1.42 6.98 2.47 55.72 45 ° L ^* 59.35 58.70 59.57 41.60 42.20 52.03 a ^* -13.43 -13.54 -14.92 2.60 1.29 12.77 b ^* -10.96 -15.59 -14.72 1.48 0.14 15.17 75 ° L ^* 47.84 48.49 52.10 31.75 31.47 34.95 a ^* -16.72 -16.61 -17.49 -0.62 -0.70 2.95 b ^* -21.37 -25.56 -21.59 -1.28 -1.79 0.99 110 ° L ^* 44.48 45.54 48.82 28.40 27.84 32.27 a ^* -18.50 -17.94 -18.65 -1.25 -1.25 -1.07 b ^* -24.50 -28.31 -23.23 -2.29 -2.68 -2.44

Example 3

The printed specimen obtained by printing in the same manner as in Example 1 was subjected to alkali and acid resistance treatment according to Comparative Example 2, and then the light variable effect was tested. The results are shown in Tables 6 and 7 below, and the CIE L ^* a ^* b ^* colorimetric chromaticity diagrams for the results are shown in FIGS. 7 and 8.

Measuring angle L ^* a ^* b ^* (# 1Blue / Green) / (# 2Gold / Green) 0/100 30/70 50/50 70/30 100/0 15 ° L ^* 78.12 80.12 91.59 85.82 88.57 a ^* -3.63 -6.29 -6.38 -9.38 -9.71 b ^* 11.08 11.28 23.19 8.32 11.63 25 ° L ^* 63.10 66.52 74.97 74.17 77.85 a ^* 2.05 -1.87 -2.01 -8.22 -10.58 b ^* 6.98 7.22 13.59 1.96 4.26 45 ° L ^* 41.60 45.54 50.99 56.32 59.35 a ^* 2.60 -1.63 -2.91 -9.84 -13.43 b ^* 1.48 -0.08 -1.88 -10.05 -10.96 75 ° L ^* 31.75 34.40 39.61 46.82 47.84 a ^* -0.62 -4.31 -7.17 -12.17 -16.72 b ^* -1.28 -5.57 -9.86 -17.15 -21.37 110 ° L ^* 28.40 30.59 36.36 43.28 44.48 a ^* -1.25 -5.21 -8.60 -13.29 -18.50 b ^* -2.29 -7.42 -12.39 -19.10 -24.50

Measuring angle L ^* a ^* b ^* (# 1Blue / Green) / (# 2Gold / Green) 0/100 30/70 50/50 70/30 100/0 15 ° L ^* 79.14 77.93 89.87 80.42 87.41 a ^* -7.17 -8.86 -8.31 -10.93 -9.84 b ^* 4.85 5.21 8.91 3.36 7.80 25 ° L ^* 64.83 65.60 75.90 70.49 76.50 a ^* -1.71 -5.06 -5.38 -10.14 -10.94 b ^* 2.47 2.06 4.06 -1.47 0.00 45 ° L ^* 42.20 47.57 53.79 55.08 58.70 a ^* 1.29 -3.42 -5.76 -10.42 -13.54 b ^* 0.14 -3.40 -5.82 -11.10 -15.59 75 ° L ^* 31.47 37.84 42.42 46.10 48.49 a ^* -0.70 -5.16 -8.55 -12.16 -16.61 b ^* -1.79 -7.45 -12.75 -17.75 -25.56 110 ° L ^* 27.84 34.04 39.20 42.10 45.54 a ^* -1.25 -5.93 -9.51 -13.29 -17.94 b ^* -2.68 -9.10 -15.29 -20.04 -28.31

The CIE L ^* a ^* b ^* values of the first tunable pigment using pearl mica as a substrate showed a linear color change with a specific slope, and the color was higher than that of the second tunable pigment. The change effect was small. As an unusual result, it was indicated by color coordinates opposite to the color perceived by the naked eye (ie, blue color as the front color and gold color as the side color when visual observation was observed, but the measurement result of the front color is gold and the side color is blue. ), Which may be different from the mechanical measurements due to the difference in perception and reflection of the pigment's refraction, reflection, and glossiness.

As a result of analyzing the CIE L ^* a ^* b ^* values when the second optically variable pigment was used, a spiral color circle was shown as the angle was changed, and the color change effect was higher than that of the first optically variable pigment. Although it was large, it was evaluated that the perception of visual color change could be decreased because the width of the color change was sensitive to the angle.

On the other hand, in the case of mixing and using the first light variable pigment and the second light variable pigment according to Examples 1 and 2, the intrinsic characteristics of the first light variable pigment and the second light variable pigment is represented by the mixing ratio, When the mixing ratio of the pigment is 50/50, it was confirmed that the linearity property of the first light-variable pigment and the spiral color circulation property of the second light-variable pigment were mixed to produce a median light variable effect. In terms of visual aspects, it was confirmed that the light variable effect is superior to that of using alone.

As a result of Comparative Example 2 and Example 3, in the case of the ink using the first light variable pigment alone, it was confirmed that the light variable effect does not decrease even when treated with acid, alkali and solvent, but the second light variable pigment alone In the case of the used ink, a chemical reaction is caused by an acid or an alkali, and thus the light variable effect is rapidly reduced. Therefore, when the securities or banknotes are printed with the ink using the second light variable pigment alone, the light variable effect disappears during the distribution period, and thus has a weakness of preventing the authenticity of the product. However, when the ink is prepared by mixing the first light variable pigment and the second light variable pigment, the chemical resistance of the first light variable pigment is enhanced to not only improve the durability of the light variable effect, but also to improve the chemical resistance and light variable. Significant improvements were obtained in terms of diversification of effects.

The optically variable ink composition of the present invention is a metal light absorber, a dielectric and a metal reflector by physical vapor deposition and a first optically variable pigment having a metal-phthalocyanate colored layer by a chemical coating method on a pearl mica, which has been conventionally used alone. By using the second light-variable pigment composed of a multi-layer thin film of the composite, it is possible to solve the problems appearing when used alone, and to improve and improve various physical properties such as variety, chemical resistance, and economy of the light variable effect at the same time. In particular, commercial applications are expected in the field of authenticity of anti-counterfeiting and security documents.

Simple modifications and variations of the present invention can be readily used by those skilled in the art, and all such variations or modifications can be considered to be included within the scope of the present invention.

1 is a CIE L ^* a ^* b ^{* of} a light variable ink prepared using only the first light variable pigments (# 1 Blue / Green, # 1 Blue / Violet and # 1 Blue / Green), respectively, according to Comparative Example 1 of the present invention. It is a colorimetric chromaticity diagram.

FIG. 2 shows CIE L ^* a ^* b ^* of optically variable inks prepared using the second optically variable pigments (# 2Gold / Green, # 2Green / Violet, # 2Violet / Green) alone according to Comparative Example 1 of the present invention. It is a colorimetric chromaticity diagram.

FIG. 3 shows the mixing ratios of the first optically variable pigment (# 1 Blue / Green) and the second optically variable pigment (# 2 Gold / Green) according to Example 1 of the present invention, respectively, at 100/0, 50:50 and 0/100 ( CIE L ^* a ^* b ^* colorimetric chromaticity diagram of light variable inks prepared by weight).

FIG. 4 is a 50:50 fixation of a mixing ratio of a first light variable pigment and a second light variable pigment by weight according to Example 2 of the present invention, and various combinations of the first light variable pigment and the second light variable pigment CIE L ^* a ^* b ^* colorimetric chromaticity diagram of the photo variable ink prepared as described above.

5 is a CIE L obtained after a chemical resistance test (sodium hydroxide, hydrochloric acid, and acetone) of a light variable ink prepared by using a first light variable pigment (# 1 Blue / Green) alone according to Comparative Example 2 of the present invention. ^* a ^* b ^* Colorimetric chromaticity diagram.

6 is a CIE L obtained after a chemical resistance test (sodium hydroxide, hydrochloric acid, and acetone) of a light variable ink prepared by using a second light variable pigment (# 2 Gold / Green) alone according to Comparative Example 2 of the present invention. ^* a ^* b ^* Colorimetric chromaticity diagram.

7 is a CIE L ^* a ^* b ^* colorimetric chromaticity diagram obtained after an alkali test (sodium hydroxide) treatment of a printed specimen obtained by printing in the same manner as in Example 1 according to Example 3 of the present invention.

8 is a CIE L ^* a ^* b ^* colorimetric chromaticity diagram obtained after an acid test (hydrochloric acid) treatment of a printed specimen obtained by printing in the same manner as in Example 1 according to Example 3 of the present invention.

Claims (7)

 1. A light-tunable complex pigment comprising a first light-variable pigment having a metal-phthalocyanine colored layer formed by a chemical coating on pearl mica and a second light-tunable pigment composed of a multilayer thin film of a metal absorber, a dielectric and a metal reflector by physical vapor deposition. Light variable ink composition, characterized in that. The method of claim 1, wherein the first light-variable pigment is a metal-phthalocyanine colored layer is formed on a metal oxide layer coated on natural mica or synthetic mica, the side color is gold, red, blue And a color repeatedly appearing in the order of green, and blue, blue-green, or green appear as the front color. The optically variable ink composition of claim 1, wherein the second optically variable pigment is stacked in the order of the metal absorber / dielectric / metal reflector / dielectric / metal absorber, and the photovariable color is adjusted according to the thickness of the dielectric. . The optically variable ink composition according to claim 1, wherein the ink composition further comprises a filler selected from the group consisting of pearl pigments, gold powder, silver powder, copper powder and transparent silica. The light variable ink composition of claim 1, wherein a mixing ratio of the first light variable pigment and the second light variable pigment in the light variable composite pigment is 10/90 to 90/10 by weight. The light variable ink composition according to claim 1, wherein the light variable composite pigment comprises two paper-like first light variable pigments and / or two or more types of second light variable pigments. The optically variable ink composition according to claim 1, wherein the ink composition further comprises an auxiliary material selected from the group consisting of a viscous agent, a desiccant, a wax, a diluent, a surfactant, and a plasticizer.