JP2006104250A - Coating composition - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a coating composition containing a granular pigment excellent in working property and dispersibility in addition to weather resistance, heat resistance, and especially excellent in reflective brightness and visually recognizable property at night, especially excellent as a road surface mark-coating composition. <P>SOLUTION: This pigment composition consists of the granular pigment obtained by crushing/classifying a dispersed material obtained by kneading/dispersing pigment powder consisting of at least 1 kind of an organic pigment powder selected from a group consisting of C. I. Pigment Yellow 110 which is an isoindolinone-based pigment, C. I. Pigment Yellow 139 which is an isoindolin-based pigment and C. I. pigment Yellow 181 which is a monoazo-based pigment, in a molten resin with an amount more than its oil absorbing amount as a main component. The coating composition containing the pigment composition, especially the road surface mark coating composition is also provided. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  In addition to weather resistance and heat resistance, the present invention is excellent in workability such as scattering prevention, handling, and dispersibility in paint resins, and particularly has excellent reflection luminance value, night visibility, etc. The present invention relates to a coating composition comprising a granular pigment as a main component.

  Organic pigments are characterized by highly saturated color development, and in regard to durability, which has been a weak point, in recent years, performance has dramatically improved and durability that is not inferior to inorganic pigments has appeared. The application is also applied to harsh outdoor applications such as coating compositions used for road marking lines and markings that require weather resistance and heat resistance, so-called road marking coating compositions. On the other hand, pigments also contain components that may adversely affect human health, and sufficient attention should be paid to the safety and environmental issues related to pigments. In particular, since there is a possibility of ingestion into the human body by inhalation of dust or aerosol, contamination of the work environment due to scattering at industrial sites and work sites where pigments are directly handled is a concern. In addition, a decrease in workability due to dust generation is also a major problem.

  Regarding the application of organic pigments to road marking paints, for example, the use of yellow organic pigments that do not contain harmful heavy metals such as lead and chromium has been proposed (for example, see Patent Document 1). In this technology, certain yellow organic pigments such as isoindoline, isoindolinone or monoazo pigments have excellent heat resistance, weather resistance and retroreflective properties, so they can be used in place of conventional yellow lead. It is disclosed that it is particularly suitable as a pigment for road marking paint compositions. However, even with this technique, the scattering of the pigment itself cannot be prevented.

  As a measure to prevent the scattering of pigment, for example, a measure in which the pigment is put in a small bag is prepared and the pigment powder in the small bag is handled at the work site, thereby reducing the chance of directly handling the pigment powder as much as possible. Sometimes. However, it takes time and effort to pack the pigment in a small bag in advance, and it is not always sufficient to prevent scattering.

  On the other hand, as a technique for improving the workability by granulating the pigment fine powder to prevent scattering and adhesion, for example, after heating the colored pigment and the resin to the melting point of the resin or higher, uniformly stirring and mixing In addition, a technique for rapidly cooling and solidifying and stirring again to form granules is known (see, for example, Patent Document 2). However, this technique is primarily intended for inorganic pigments, and secondly, as can be seen from the small amount of compounded resin and the production method similar to the rolling granulation method, The pigment has a structure in which the pigment is fused together, and the dispersion degree of the pigment itself is not always sufficient when the granular pigment is blended in the coating composition. Further, this method is not suitable for granulating organic pigment crystals having a relatively large aspect ratio.

  Furthermore, there is a technique for producing pigment granules by spray drying an aqueous suspension of an organic pigment and a wax (see, for example, Patent Document 3). This method is basically performed during the finishing step of the corresponding pigment powder preparation process, and a granule having a structure in which the pigment surface is coated with wax is obtained. However, in this case, it is a method that is applied in the manufacturing process of the pigment, and is not a technique that is applied to the already manufactured pigment. Therefore, the toning according to the intended use is appropriately performed using the manufactured pigment. There are problems that it is difficult to use in fields that need to be performed, and that pigments coated with wax cannot be used for road marking applications because they have releasability. As described above, the granulation method employed in the past does not sufficiently lead to the excellent characteristics of organic pigments, and it has not been possible to obtain granules that can maintain and exhibit special characteristics such as road marking applications. .

JP-A-10-114863 JP-A-54-37136, page (2) Japanese Patent Application Laid-Open No. 2001-81349

  In view of the above situation, the present invention is a granular pigment mainly composed of an organic pigment, which is excellent in workability and dispersibility in addition to weather resistance and heat resistance, and particularly excellent in reflection luminance value and night visibility. An object of the present invention is to provide a coating composition to be contained, particularly a road marking coating composition.

  As a result of diligent studies to solve the above problems, the present inventor pulverized and classified a dispersion in which a molten resin and an organic pigment powder were uniformly kneaded to granulate an organic pigment powder having a relatively large aspect ratio. The present invention has been completed by finding that it is excellent in dispersibility in paint resins.

That is, the present invention relates to a coating composition comprising a granular pigment obtained by pulverizing and classifying a dispersion obtained by dispersing an organic pigment powder in a molten resin and a coating resin, particularly a road marking coating composition. is there.
In one embodiment of the present invention, the granular pigment is obtained by pulverizing and classifying a dispersion obtained by dispersing a toning pigment powder with respect to the organic pigment powder in addition to the organic pigment powder in the molten resin. It will be.
In another embodiment of the present invention, the organic pigment is an isoindolinone pigment. I. Pigment Yellow 110, a C.I. I. Pigment Yellow 139 and C.I. which is a monoazo pigment. I. Pigment Yellow 181 is at least one selected from the group consisting of Pigment Yellow 181.

  The present invention also includes C.I. which is an isoindolinone pigment. I. Pigment Yellow 110, a C.I. I. Pigment Yellow 139 and C.I. which is a monoazo pigment. I. The dispersion obtained by kneading and dispersing the pigment powder in a molten resin having an oil absorption amount or more of a pigment powder mainly composed of at least one organic pigment selected from the group consisting of Pigment Yellow 181 is pulverized and classified. It is also a pigment composition mainly composed of a granular pigment.

Since this invention is the above-mentioned structure, the following effects are exhibited.
(1) It is possible to effectively prevent contamination of the work environment and deterioration of workability due to pigment scattering at industrial sites and work sites.
(2) The coating composition of the present invention is excellent in dispersibility of an organic pigment in a coating resin and has good color development.
(3) The coating composition of the present invention is a yellow organic pigment, particularly C.I. which is an isoindolinone pigment. I. Pigment Yellow 110, a C.I. I. Pigment Yellow 139 or C.I. which is a monoazo pigment. I. Pigment Yellow 181 granules can be used to provide a road marking coating composition excellent in reflection luminance value, night visibility as yellow, and the like.
(4) In the pigment composition of the present invention, the granular pigment is extremely excellent in dispersibility of the pigment in the resin constituting the granule.
(5) C.I. which is an isoindolinone pigment. I. Pigment Yellow 110, a C.I. I. Pigment Yellow 139 or C.I. which is a monoazo pigment. I. The pigment composition of the present invention having a granular pigment mainly containing Pigment Yellow 181 as a main component has an extremely high reflection luminance value and night visibility as yellow, and is effective with a smaller blending amount than before.
Hereinafter, the present invention will be described in detail.

  The granular pigment in the present invention can be obtained by pulverizing and classifying a dispersion in which a pigment powder for toning with respect to the organic pigment powder is further dispersed in addition to the organic pigment powder or the organic pigment powder in the molten resin. It can be done. Accordingly, in the present invention, the granular pigment is a pulverized / classified dispersion in which the organic pigment powder is the main component of the molten resin, and the toning pigment powder for the organic pigment is further blended as necessary. In this case, particles containing a pigment mainly composed of an organic pigment and a resin having a larger particle diameter than those of the original pigment powder particles. By adopting this granulation method, an organic pigment crystal powder having a relatively large aspect ratio is uniformly dispersed in the resin. Typically, the resin and the pigment crystal particles form a so-called sea-island structure. Granules can be produced. In such a granular pigment, since the pigment fine particles are already separated from each other by a resin, good dispersion can be quickly achieved when the mixture is stirred and mixed with a coating resin, and thus color development is excellent. In the present specification, the coating resin means a resin in which the granular pigment is dispersed to form a coating composition. In addition, when a yellow organic pigment described in detail later is used, the night visibility as yellow, the reflection luminance value, and the like are greatly improved as compared with the case where no granulation is performed.

  Examples of the resin mixed with the pigment in the granular pigment include petroleum resin, rosin resin, coumarone resin, indene resin, and terpene resin. These resins may be liquid or solid at room temperature, and the resin only needs to be liquid when dispersing the pigment powder. Accordingly, in the present invention, the molten resin includes not only a resin having a melting point higher than room temperature and melted by heating, but also a resin having a melting point lower than room temperature and a liquid or water tank at room temperature. . From the viewpoint of maintaining the granules, the resin is preferably a solid resin at room temperature. For example, a resin having a softening point of about 60 to 200 ° C is preferable, and 80 to 150 ° C is more preferable. In addition, it is preferable to select a resin in consideration of compatibility with a coating resin.

  The organic pigment is not particularly limited and various types can be used.For example, isoindolinone pigment, isoindoline pigment, thioindigo pigment, quinophthalone pigment, anthraquinone pigment, dioxazine pigment, phthalocyanine pigment, quinacridone pigment, perylene pigment Examples thereof include perinone pigments, diketopyrrolopyrrole pigments, condensed azo pigments, and monoazo pigments. For road marking paint compositions, C.I. is an isoindolinone pigment. I. Pigment Yellow 110, a C.I. I. Pigment Yellow 139 or C.I. I. Pigment Yellow 181 is preferable, and these can be used alone or in combination of two or more. Since these yellow pigments are excellent in weather resistance, heat resistance and retroreflective properties, they are extremely suitable for yellow road marking coating compositions.

For road marking paint compositions, in addition to the above yellow pigments in the above granular pigment, in order to color the road marking yellow according to the notification of the competent authority, if necessary, further, titanium oxide, iron oxide, Toning organic pigments such as inorganic pigments such as titanium yellow and bismuth vanadate (BiVO ₄ ), perylene pigments, perinone pigments, quinacridone pigments, diketopyrrolopyrrole pigments, condensed azo pigments and monoazo pigments Can be used in the amount needed to do.

  C. I. Pigment Yellow 139 is an organic compound having the following structural formula.

  In addition, C.I. I. Pigment Yellow 181 is an organic compound having the following structural formula.

  C. I. Pigment Yellow 110 is an organic compound having the following structural formula.

  As the granulating method of the granular pigment, (1) In addition to the organic pigment powder or the organic pigment powder in the molten state of the resin (that is, the liquid resin state), further adjustment to the organic pigment powder is performed. Examples of the production method include a step of uniformly dispersing the color pigment powder to obtain a dispersion, and (2) a step of pulverizing and classifying the obtained dispersion. The step (1) can be performed using various mixers and dispersers. For example, a kneading disperser such as a two or three roll mill, a high-speed stirring disperser, a twin screw extruder, and a Banbury. A mixer, a pressure kneader, or the like can be used. Among these, from the viewpoint of uniform dispersion of the resin and the pigment, kneaded meat dispersion, for example, kneaded meat dispersion using a three-roll mill is preferable.

  The compounding ratio (weight ratio) of the resin and the organic pigment powder or organic pigment powder and toning pigment during granulation is preferably 40:60, more preferably 50:50, and still more preferably 60:40. . When the blending ratio is within the above range, it is advantageous in forming a sea-island structure of resin and pigment particles. In the present invention, the amount of the resin is more than the amount of oil absorption of the pigment powder, that is, the organic pigment powder, preferably the organic pigment powder and the toning pigment powder, if applicable. Is preferred. The above range is advantageous in forming a sea-island structure of resin and pigment particles. On the other hand, if the amount of resin is less than the amount of oil absorption, the pigment powder is coalesced to form particle aggregates, and it is difficult to form granules in which the resin and organic pigment are uniformly dispersed. The amount of oil absorption varies depending on the type of pigment. Therefore, in the present invention, it is preferable that the blending ratio (weight ratio) is equal to or greater than the oil absorption amount while taking the oil absorption amount into consideration. The oil absorption amount of the pigment refers to the amount of oil necessary for mechanically wet-mixing the pigment with the liquid to form a hard paste, and can be measured according to JIS K 5101.

  The dispersion obtained in the step (1) is cooled and solidified below the melting point, and then pulverized and classified in the step (2). As an apparatus for pulverization / classification, for example, pulverization / classification apparatuses such as a vertical roller mill, a centrifugal roller mill, a turbo mill, a pulverizer, a pin mill, a feather mill, and a plastic mill can be used. In the pulverization, when excessive pulverization energy is applied, the granule disintegrates. Therefore, it is desirable that an appropriate pulverization energy can be applied, but adjustment thereof can be appropriately performed by those skilled in the art.

  Moreover, it is also possible to perform the said (1) and (2) process continuously integrally, for example, it is also possible to perform dispersion | distribution and granulation by granulators, such as a high-speed stirrer. Therefore, a granular pigment obtained by such a production method is also applicable as long as the object of the present invention is not impaired.

  In the present invention, the granular pigment preferably has a volume average particle size of 0.1 to 10 mm, more preferably 0.1 to 3 mm. When the average particle size is in the above range, the diffusion and dispersion of the granular pigment in the coating composition is good.

  The pigment composition of the present invention contains the above-mentioned granular pigment as a main component, and may contain a toning pigment, an extender / reinforcing extender pigment, and the like, if necessary.

  In the coating composition of the present invention, the coating resin is not particularly limited, and a coating resin usually used in a coating composition can be used. In the case of a melt-type (3 types) road marking paint, thermoplastic resins such as aliphatic petroleum resin, rosin resin, coumarone resin, indene resin, and terpene resin can be used.

  In the coating composition of the present invention, examples of the road marking coating composition include C.I. I. Pigment Yellow 181 and C.I. I. It is preferable to contain at least one of Pigment Yellow 139 as a main component.

  C. I. It is preferable that Pigment Yellow 139 has a volume average particle size of the pigment crystal powder of 0.05 to 2 μm. The thickness of 0.05 μm or more is advantageous for sufficiently exhibiting retroreflectivity, and it is technically difficult to form particles having a size of more than 2 μm. More preferably, it is 0.1-1 micrometer.

  In the coating composition of the present invention, examples of the road marking coating composition include C.I. I. Pigment Yellow 110 may be used as a main component. C. I. When Pigment Yellow 110 is the main component, the major axis of the pigment crystal powder particles is preferably 0.1 to 2 μm. When it is 0.1 μm or more, it is advantageous to exhibit retroreflectivity, and it is technically difficult to form particles exceeding 2 μm. More preferably, it is 0.2-1 micrometer.

  In the road marking paint composition, C.I. I. Pigment Yellow 139, C.I. I. Pigment Yellow 181, and C.I. I. The content of Pigment Yellow 110 is not particularly limited, and can be appropriately selected as necessary when toning the road marking yellow according to the competent authority notification.

  In the present invention, the road marking coating composition is added with a thermoplastic coating resin as a coating resin, glass beads, and other additives used as necessary, for example, cryolite, plasticizer, extender pigment, etc. By adding a necessary amount of the above-mentioned granular pigment to the mixture, it is possible to obtain a melt type (3 types) road marking paint.

  As said extender pigment, inorganic extender pigments, such as calcium carbonate, barium sulfate, talc, mica powder, can be added, for example. It is preferable that these compounding quantities are 30 to 70 weight% in a coating composition.

  Hereinafter, the present invention will be described in more detail with reference to examples. However, the present invention is not limited to these examples.

Production Example 1
Production of granular pigment A dispersion obtained by uniformly dispersing using a three roll mill (manufactured by Inoue Seisakusho Co., Ltd.) (roll temperature 150 to 160 ° C.) with the following composition (weight ratio) was cooled and solidified to room temperature. Then, the mixture was pulverized and classified by a pulverization / classification apparatus (Feather Mill, manufactured by Hosokawa Micron Corporation) to obtain a granular pigment having a volume average particle diameter of 3 mm.
Formulation C.I. I. Pigment 181 (oil absorption 115 ml / 100 g) 45 g
Petroleum resin (melting point 95 ° C, manufactured by Mitsui Chemicals) 55g

Examples 1-5, Comparative Examples 1-7
About the coloring material, the mixture of the following composition is heated and mixed at a mantle heater at 180 ° C. while being stirred for 5 minutes while mixing and mixing the coloring materials shown in Table 1, and road marking paint composition. The thing was manufactured. The composition of the coating composition is as follows.
Compound Resin Highlets R-500X (aliphatic petroleum resin, Mitsui Chemicals) 13 parts by weight Cryosalt 20 parts by weight Calcium carbonate 47 parts by weight Glass beads (JIS R 3301-1 compliant) 16 parts by weight Vegetable oil-modified alkyd resin ( Arakawa Chemical Co., Ltd.) 3 parts by weight Colorant (Colorant types and combinations shown in Table 1)
The abbreviations in Table 1 are as follows.
A: C.I. I. Pigment 181
B: Granular C.I. I. Pigment 181
C: Pigment using bismuth vanadate D: Yellow lead

Evaluation method On a tin plate of 70 mm × 150 mm × 0.3 mm, a coated plate was prepared with an applicator for three types of JIS K 5665. In addition, in observation of night visibility as a color tone and yellow, the above-mentioned coating composition was applied on a flat plate, and the glass beads were uniformly dispersed and fixed at a rate of 25 g / m before the coating film cooled. Observed.
(1) Color tone The visibility of the sample coated plate as yellow in the daytime was evaluated by visual observation, and the following criteria were used.
A: The color tone is clear B: The color tone is not clear (2) Night visibility as yellow The visibility as yellow when the headlight of a car is irradiated at night by visually observing the sample coating plate The following criteria are shown.
A: Visibility equivalent to that of paint using conventional chrome lead B: Slightly inferior but visible as yellow C: Not visible as yellow (3) Applicability Work when applying the above paint on a flat plate Sexuality was evaluated subjectively and indicated by the following criteria.
A: Good B: Good C: Inferior (4) Reflected luminance value Using a luminance meter (Mirolux (trade name), manufactured by Potters Barotini) with the coated surface in a dry state, an incident angle of 86.5 degrees, an observation angle of 1 The brightness of the coating surface was measured by further receiving the light from the light projector irradiated to the front coating surface at 5 degrees by the front light receiver (unit: mcd / lx · m ² ).

  The nighttime visibility and the reflection luminance values of Examples 1 to 5 are 1.3 to 1.4 times better than Comparative Examples 1 to 5 having the same blending amount, respectively. In order to ensure the value, it is necessary to add about 1.5 times the colorant in the aspect of the comparative example. Further, even when the blending amount is relatively small as in Examples 1 and 2, the night visibility as yellow is excellent, whereas the aspects of Comparative Examples 1 and 2 are insufficient in night visibility. . Thus, since the granular pigment in the present invention has a very good dispersion as compared with the case where it is not granulated, it shows a remarkable improvement in color tone, night visibility, reflection luminance value and the like.

  The coating composition of the present invention can prevent scattering when using organic pigments and adverse effects on workability, and is excellent in pigment dispersibility, so that not only the working environment is improved, but also the characteristics of the coating composition. And is extremely useful for implementation in the industrial field.

Claims (8)

A coating composition comprising a granular pigment obtained by pulverizing and classifying a dispersion obtained by dispersing organic pigment powder in a molten resin, and a coating resin. 2. The granular pigment is obtained by pulverizing and classifying a dispersion obtained by dispersing, in addition to an organic pigment powder, a toning pigment powder for the organic pigment powder in a molten resin. Paint composition. The organic pigment is C.I. which is an isoindolinone pigment. I. Pigment Yellow 110, a C.I. I. Pigment Yellow 139 and C.I. which is a monoazo pigment. I. The coating composition according to claim 1, wherein the coating composition is at least one selected from the group consisting of Pigment Yellow 181. C. I. The coating composition according to claim 3, wherein Pigment Yellow 139 has a volume average particle size of 0.05 to 2 μm. C. I. The coating composition according to claim 3, wherein the pigment yellow 110 has a major axis of 0.1 to 2 μm. The granular pigment is obtained by pulverizing and classifying a dispersion obtained by kneading and dispersing the pigment powder in a molten resin having an oil absorption amount or more of the pigment powder. Paint composition. The coating composition according to any one of claims 1 to 6, which is a road marking coating composition. C. is an isoindolinone pigment. I. Pigment Yellow 110, a C.I. I. Pigment Yellow 139 and C.I. which is a monoazo pigment. I. The dispersion obtained by kneading and dispersing the pigment powder in a molten resin having an oil absorption amount or more of a pigment powder mainly composed of at least one organic pigment selected from the group consisting of Pigment Yellow 181 is pulverized and classified. A pigment composition mainly composed of a granular pigment.