JPH0335349B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to extender pigments containing zeolite as a main component. Generally, extender pigments are non-coloring pigments,
It is used with other coloring pigments in paint and printing ink formulations or as a base for lake pigments, making the primary colors of the coloring pigments effective. It exerts effects such as reinforcing the paint film, smoothing the surface of the base and paint film, and giving appropriate viscosity and fluidity to the paint and printing ink. It is necessary for the pigment to meet the following requirements. (1) It should be as transparent as possible in a vehicle such as linseed oil or varnish; (2) The pigment particles should be fine-grained, easy to mix with vehicles and other pigments, and have good dispersibility; (3) It must have an appropriate oil absorption value and the desired flow characteristics can be obtained with an appropriate amount of blending; (4) It must be insoluble in vehicles and solvents, and it must not be reactive with them; (5) It must be resistant to light and heat.・It must be resistant to chemicals, etc. (6) It must not interfere with the drying properties of printing ink, and (7) It must be non-toxic. Conventionally, barium sulfate, calcium carbonate, alumina white, white carbon, and the like have been mainly used as extender pigments, but these extender pigments have advantages and disadvantages, and none of them are comprehensively satisfactory. That is, barium sulfate has been used as an extender pigment for a long time, but when kneaded with linseed oil, it becomes a translucent paste, which is easy to knead, but is not very suitable as a general-purpose ink. Calcium carbonate is also easy to mix, but it is translucent in linseed oil, making it unsuitable for printing inks that require a high degree of transparency. It also has the disadvantage that it tends to produce a slightly matte coating. When alumina white is kneaded with linseed oil, a nearly transparent paste can be obtained, but when kneaded with varnish with a high acid value, it has the disadvantage of causing rebarring and slowing down the drying of the ink. Furthermore, the gloss of the coating film is likely to be lost, and other pigments may become discolored. White carbon, on the other hand, is quite transparent in the vehicle, but has significantly higher oil absorption values (100-200
Since the viscosity increases when added in a small amount (ml/100g), the amount added is limited to a small amount, and there is a drawback that a sufficient color spreading effect on colored or white pigments and a reinforcing effect on the coating film cannot be obtained. On the other hand, it has been known to add a small amount of a certain type of zeolite (molecular sieve) to paints, but this is mainly done by adding dehydrated and activated zeolite as a kind of drying agent. The purpose of the present invention is to prevent the can from bursting or the lid from blowing off due to gas generation during storage due to trace amounts of moisture.
The implementation modes and effects are completely different. It is also known that a certain type of amorphous aluminosilicate fine powder (zeolex) is used as a filler in paints, but this type of aluminosilicate is different from zeolite and is rather similar to white carbon. The diameter of the primary particles is 0.02 to 0.04 μm.
It consists of ultra-fine particles, and the oil absorption value is about 100 to 150.
ml/100g, and the structure, properties, purpose of use, effects, etc. of the substance are also significantly different from the extender pigment of the present invention. The present inventors conducted various experiments and studies in order to develop a new high-performance extender pigment that overcomes many of the drawbacks of conventional extender pigments. They discovered that the modified product is extremely suitable as an extender pigment and completed the present invention. That is, the present invention provides homogeneous, fine, substantially spherical particles of A-type zeolite and/or It is an extender pigment characterized by Generally, zeolite has the general formula (1.0±0.2)
M ₂ O・Al ₂ O ₃・xSiO ₂・yH ₂ O (where M is Na or an equivalent monovalent or polyvalent metal, x is often a value of 1.5 to 20, and y is a value of 0 to 10). They are aminosilicates with a unique crystal structure that can be identified by chemical composition and X-ray diffraction, and various types are known, including natural minerals and synthetic products (usually M is Na ). Furthermore, since zeolite generally has unique adsorption and ion exchange performance based on its unique crystal structure, various uses have been developed that take advantage of these characteristics. In the present invention, the zeolite is homogeneous, fine, substantially spherical particles of type A zeolite or/and type X zeolite, and has an oil absorption value of 10 to 10.
80 ml/100 g and a refractive index value of 1.42 to 1.53. However, in this case, uniform fine particles mean that the part with a particle size of 10 μm or more is 1
% or less, and has a particle size distribution such that the particle size portion of 6 μm or less is 85% or more. It is unsuitable to use paints or printing inks that contain large amounts of coarse particles of 10 μm or more because they tend to cause unevenness on the painted or printed surface and increase wear on rollers and stirrers. In addition, particles with non-uniform particle size distribution tend to have poor dispersion in the vehicle, requiring addition of a large amount of dispersion aid and kneading for a long time, resulting in increased costs and reduced efficiency. Furthermore, the term "substantially spherical particles" refers to particles or spherical particles in which the corners and edges of the A-type zeolite single-crystal particles, which are generally cubic like sugar cubes, have disappeared and become rounded. In addition, the optimum oil absorption value is 10 to 80ml/100g, but this is because most common pigments have oil absorption values similar to this, and are easy to knead with a vehicle and have appropriate fluidity. This is because it provides properties that are essential for extender pigments. On the other hand, the refractive index value is an important property that governs the transparency of extender pigments, and the closer the refractive index value of the linseed oil or varnish used, the better the transparency can be obtained. In order to obtain good transparency, it is necessary that the refractive index value (n _D ) be between 1.42 and 1.53. Therefore, zeolites with values outside this range are basically unsuitable as extender pigments. Zeolite particles having the above-mentioned particle characteristics, which are the object of the present invention, can be prepared by various methods under controlled conditions.
Synthetic zeolites such as type A zeolite and type Furthermore, some or most of the Na ₂ O components in these zeolites are converted to Na ⁺ by an ion exchange reaction.
It is also possible to use cation-substituted zeolites substituted with other cations. In this case, the types of cations other than Na ⁺ are
Monovalent cations such as H ⁺ , Li ⁺ , K ⁺ , Mg ²⁺ ,
Various divalent cations such as Ca ²⁺ , Sr ²⁺ , Ba ²⁺ , Zn ²⁺ , Cd ²⁺ , Pb ²⁺ etc. can be mentioned, but it depends on the type of cation and degree of substitution. Since the value of the refractive index of the zeolite particles varies, a high degree of transparency can be achieved by adjusting the value to be very close to the refractive index of the vehicle ultimately used. In addition, if necessary, these zeolite particles can be
A higher quality extender pigment can be obtained by adjusting the pH value or performing various modification treatments on the surface of the zeolite particles. In particular, zeolite particles coated with a dense amorphous silica film have an extremely inert surface and are more resistant to light, heat, chemicals, etc., regardless of the type of original zeolite. Even when mixed with other materials or various formulations, the properties of paints and printing inks will not deteriorate. Although various methods are possible for forming such a dense amorphous silica film on the surface of zeolite particles, for example, the method disclosed in US Pat. No. 2,885,366 can be applied. Furthermore, the zeolite used as an extender pigment in the present invention includes not only the above-mentioned zeolite itself but also a modified zeolite obtained by modifying such a zeolite. Here, zeolite modification means neutralizing the zeolite with a desired acidic substance to adjust the basicity of the zeolite particles, and coating the zeolite particle surface with fine silica sol or white metal hydroxide. treatment or surfactant,
This refers to the addition of a particle surface modifier such as a dispersant, thereby maintaining the properties of the zeolite itself and substantially suppressing its drawbacks such as basicity or cation elution. As a result, various pigment properties such as light resistance, heat resistance, acid resistance, alkali resistance, and dispersibility can be further improved. Therefore, for example, in the neutralization treatment of zeolite, the basicity can be adjusted by treating the slurry with a mild acid, and in the silica coating treatment, the zeolite aqueous slurry is heated and a sodium silicate aqueous solution and acid are gradually added. This process allows a fine, dense silica film to be formed on the surface of the zeolite particles. Among modified zeolites, zeolite particles coated with a dense amorphous silica film are particularly stable, regardless of the type of zeolite core, and are resistant to light, heat, chemicals, etc. It has even more fastness, and its properties as a paint or printing ink will not deteriorate even when mixed with a vehicle with a high acid value or various formulations. As is clear from the above description, the following points are pointed out as characteristics of the extender pigment of the present invention. (i) It is much more transparent than conventional extender pigments such as barium sulfate and calcium carbonate. In particular, the extender pigments of the present invention, whose refractive index is adjusted to a value similar to that of linseed oil and varnish used in paints and printing inks, are almost completely transparent in these vehicles. (ii) Pigment particles are fine-grained, have an oil absorption value on the same level as general pigments, are easy to mix with vehicles and other pigments, and have good particle dispersibility. This point is markedly different from alumina white and white carbon, which have large oil absorption values. (iii) Since the specific gravity value is relatively small at approximately 2, the same filling effect can be obtained with approximately 1/2 the amount used compared to barium sulfate. (iv) is insoluble in vehicles and solvents; (v) Resistant to light and heat. In particular, zeolite particles coated with dense amorphous silica have extremely inert surfaces, are not attacked by various chemicals, and do not inhibit the drying properties of printing inks. Therefore, even if it is kneaded with an oil having a high acid value, it will not cause rebang, solidify the surface, or promote gelation. (vi) non-toxic; The extender pigment of the present invention, which has many of these characteristics, can be used not only for general paints and printing inks, but also for special pigments and high-grade printing inks that require high quality characteristics, or for transparent lake pigments. It can be said that it is an epoch-making extender pigment that can be widely used as a sexual base material. Hereinafter, the present invention will be explained by showing production examples, examples, comparative examples, and reference examples. The results of these examples were evaluated using the following test method. Oil absorption: 19 of JIS K5101-78 Specific gravity: 17 of JIS K5101-78 Refractive index: Measured by Larsen's oil immersion method using an Atsube refractometer. Particle size distribution: Measured using a Coulter Counter (manufactured by Coulter Electronics) with an aperture tube diameter of 20 μm. Color difference: Digital colorimeter (Suga Test Instruments Co., Ltd.)
The color difference was measured using Transparency 1
When color pigments are not included (Note) Measure the color difference of each sample pigment applied on the black side with the black side of the hiding power measurement paper as the reference, and define the one with a small color difference as having high transparency. did. 2. When containing colored pigments, measure the color difference between the colors applied to the black side of the hiding power measurement paper coated with each sample pigment based on the color applied to the white side, and those with large color differences are considered transparent. defined as large. (Note) Hiding power measurement paper Art paper with white and black sides (approx. 217 x 197 mm)
The 45 degree diffuse reflectance was 79.69% for the white surface and 1.48% for the black surface. Example 1 Table 1 shows the specific gravity, refractive index, and oil absorption of various zeolite extender pigments of the present invention. Table 1 also shows amorphous aluminosilicate pigment (trade name) as a commercially available extender pigment for comparison with the above zeolite.
Zeolex), precipitated barium sulfate, precipitated calcium carbonate, and white carbon were also shown at the same time. Table 1 shows that aluminosilicate pigments and various zeolites have a specific gravity of approximately 2, which is smaller than other extender pigments. Furthermore, the refractive index is close to that of linseed oil (1.480), and it is clear that an almost transparent coating film can be obtained when mixed with linseed oil. In addition, the various aluminosilicate-based zeolites shown in Table 1 are all crystalline particles with a particle size of 0.5 to 5 μm, and their oil absorption is usually 80 ml/100 g or less.
0.02-0.04μm oil absorption 100ml/100g or more).

[Table] The zeolite which is the extender pigment of the present invention described above was produced as follows. Using predetermined amounts of sodium silicate solution and sodium aluminate solution as starting materials, a gel is made by simultaneously bringing these two solutions into contact using the method described in JP-A-57-3713, and the resulting gel is crystallized at approximately 80°C. NaA type zeolite (No. 1-1) by keeping it until it forms
was synthesized. In addition, a gel was prepared by reacting a sodium silicate solution and a sodium aluminate solution without back-mixing according to the method described in JP-A No. 57-166311, and this gel was stirred at 25°C for about 30 minutes. After aging the gel by leaving it to stand for a while, the temperature was raised to 95°C to perform crystallization, thereby synthesizing NaX type zeolite (No. 1-3). In addition, by applying silica coating treatment to NaA type zeolite (No. 1-1), silica-coated NaA
While preparing type zeolite (No. 1-2),
By sufficiently replacing Na in NaA type zeolite (No. 1-1) with Ca through an ion exchange reaction.
CaA type zeolite (No. 1-4) was prepared. NaA type zeolite (No. 1-1), which is the extender pigment of the present invention, consists of uniformly fine spherical or rounded cubic particles having the particle size distribution shown in Table 2, and has a fine particle texture that allows it to be absorbed into linseed oil. The dispersibility was extremely good.

[Table] On the other hand, the extender pigment of the present invention, NaX type zeolite (No. 1-3), was composed of uniformly fine particles with a nearly spherical shape, and had extremely good dispersibility in linseed oil. Example 2 Na-A zeolite of Example-1 (No. 1-1)
Various Ca-A type zeolites (Ca-
The relationship between the Ca-ion exchange rate and the refractive index is shown in the attached diagram (assuming that the Ca exchange rate is 100% when the CaO/Al ₂ O ₃ molar ratio of type A zeolite is 1.0). From the diagram
The refractive index of the Ca-A type zeolite also increased as the Ca exchange rate increased, and it is clear from this result that the refractive index of the extender pigment (zeolite) of the present invention can be adjusted according to the refractive index of the vehicle. .
The state of the particles hardly changed before and after the ion-exchange reaction; they were all uniform and fine, and the dispersibility in the vehicle was extremely good, and the oil absorption amount also hardly changed before and after the ion-exchange reaction. . In addition, the Ca- of NA-A type zeolite (No. 1-1)
Ion exchange was carried out by conventional ion exchange techniques using calcium chloride solution. Test Example 1 The hiding power of the extender pigment of the present invention was measured using a cryptometer according to the method described in JISK5101 (pigment test method) 6. Use No. 4 linseed oil as the vehicle and perform the test according to the JISK5115 test method for precipitated barium sulfate. When measuring the hiding power of calcium carbonate and various zeolites, add pigment volume concentration to the mixed paste of precipitated barium sulfate. A paste was prepared and tested.
The results are shown in Table-3. From Table 3, it is clear that the hiding power of the various zeolites of the present invention is 1 mm or more, and that they have extremely excellent transparency compared to precipitated barium sulfate and calcium carbonate.

[Table] Test Example 2 Various zeolites and extender pigments of the present invention are kneaded with No. 4 linseed oil to create a uniform paste with approximately the same viscosity, and a film applicator of 0.0762 is applied onto hiding power measurement paper using a film applicator. mm
(3 moles) thick. After drying at room temperature, use a color difference meter to measure the tristimulus values X, Y, and Z of the color of the black side of the hiding power measurement paper, and from this, the L, a, b values,
The color difference ΔE was determined. The results are shown in Table 4. Table-4
The color difference (△E) with respect to the blank (the black side of the hiding power measurement paper) is superior in transparency. The precipitated calcium carbonate value was 30 or higher, which clearly shows that the zeolite type has excellent transparency. Zeolex also has a small color difference, but the black surface to which it is applied takes on a matte appearance and loses its luster.

[Table] Test Example 3 Na-A zeolite described in Example-1 (No. 1-1), 20% silica coated Na-A zeolite (No. 1-2), precipitated barium sulfate, precipitated For the four types of calcium carbonate samples, a uniform paste was made with No. 4 linseed oil and applied to the hiding power measurement paper in the same manner as Test Example 2, and after drying, the color difference △
E was measured. The pastes were prepared so that the pigment volume concentration in each pigment paste was 41.9% (settled burr). The results are shown in Table-5. Table 5 shows that when the pigment volume concentration is kept constant, precipitated barium sulfate and precipitated calcium carbonate have almost the same color difference of about 50 compared to the blank, whereas zeolite has a color difference of less than 10, which is extremely transparent. It is clear that

[Table] Test Example 4 Na-A zeolite described in Example 1 (No. 1
-1) and No. 4 linseed oil to make a uniform paste and use a film applicator to make a 0.0762
A thickness of 3 mils (mm) was applied to the opacity test paper. Immediately after application, dry in a dryer at 110℃.
The coating film was observed after drying. As a result, no blisters or pinholes due to foaming were observed on the paint film surface.
When kneaded with linseed oil, no adverse effects due to the structural water of zeolite were observed. Test Example 5 Na-A zeolite described in Example 1 (No.
1-1) Using 20% silica-coated Na-A zeolite (No. 1-2), precipitated barium sulfate, precipitated calcium carbonate, and alumina white, each pigment was kneaded uniformly with No. 4 printing varnish. The combined material was placed in a sample bottle (φ15 mm x 35 H), sealed, and a reviving test was conducted in a constant temperature bath at 80°C. As a result of observing the state of reviving every 24 hours, reviving was observed in Alumina White after 24 hours, while the other four pigments were exposed to 80℃
No reviving was observed after 72 hours, indicating that Na-A zeolite and silica-coated Na-A zeolite have the same stability as precipitated barium sulfate and precipitated calcium carbonate. . Test Example 6 Na-A zeolite described in Example 1 (No.
1-1), using precipitated barium sulfate and precipitated calcium carbonate as extender pigments, and using navy blue and chromium oxide as coloring pigments, 99 parts of each extender pigment for 1 part of the color pigment (deep blue or chromium oxide). mix,
Furthermore, No. 4 linseed oil was added and kneaded into a uniform paste using a Hoover muller, which was then applied onto the hiding power measurement paper using an applicator. The ratio of pigment and linseed oil was adjusted to the pigment volume concentration of JISK5115 precipitated barium sulfate. After drying, the color difference between the black side and the white side of the hiding power measurement paper was measured using a color difference meter. The results are shown in Table-5. Table 6 also shows the color tristimulus values X, Y, Z and L, a, b values. Table 6 shows that the color difference △E between the white side and the black side of the hiding power measurement paper shows that there is almost no color difference for precipitated barium sulfate or calcium carbonate, even when the colored pigments of navy blue or chromium oxide are diluted.
In the case of Na-A type zeolite, ΔE is 25 to 30, which is a large color difference.

[Table] This means that when mixed with colored pigments, Na-A zeolite has less hiding power than precipitated barium sulfate or calcium carbonate, that is, it has excellent transparency. This shows that when diluting with pigment, the original color tone of the colored pigment can be maintained indefinitely even when the dilution ratio is increased. For example, X, Y, Z of the white side of the hiding power measurement paper when the dark blue shown in Table 5 is diluted with extender pigment.
Looking at the values, when diluted with Na-A,
The Z value is the smallest, which indicates that the overall color tone is blackish, indicating that when dark blue is diluted, the unique color tone of dark blue does not change to whitish due to dilution. These effects mean that it is possible to significantly reduce the amount of expensive coloring pigments used when adjusting the color of paints and printing inks.

[Brief explanation of drawings]

The figure is a graph showing the relationship between the ion exchange rate and the refractive index of A-type zeolite when Na in NaA-type zeolite is ion-exchanged with Ca.

Claims (1)

[Scope of Claims] 1. Uniform, fine, substantially spherical particles containing A-type zeolite or/and An extender pigment characterized by a value of 1.42 to 1.53. 2. The extender pigment according to claim 1, wherein a part or most of the Na ₂ O component in the zeolite is substituted with a monovalent or polyvalent cation other than Na ⁺ . 3. The extender pigment according to claim 1 or 2, wherein the zeolite particles are covered with a dense amorphous silica film.