JPH0499B2 - - Google Patents

Description

[Detailed description of the invention]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a colored polymer molding material containing an organic pigment as a main colorant, and more specifically, the present invention relates to a light-fast stabilizer for a colored polymer molding material. Pigments in polymers not only provide color, but also play the role of supplementing or reinforcing physical or chemical defects such as cracks and chalking on the surface of the polymer. Pigments used for this purpose are generally inorganic pigments that have excellent physical properties such as light resistance, hiding power, and solvent resistance. However, inorganic pigments have limitations in terms of color type, brightness, etc. For this reason, there is a demand for organic pigments, and currently organic pigments have no choice but to be used to prepare colored polymers with colors that are difficult to obtain with inorganic pigments, such as red or bright colors. . Organic pigments are thus rich in hue and have excellent clarity and coloring power. However, they are inferior to inorganic pigments in physical properties such as light resistance and hiding power, and in particular, their low light resistance is a major obstacle in their use. In recent years, organic pigments with improvements in these points have been developed, but they are very expensive, so
The reality is that it is only used in extremely limited fields. Therefore, if the light resistance of commonly used inexpensive organic pigments can be improved and durable polymer colored products can be obtained, it is also possible to improve the added value of the colored products. Resource saving·
This is also significant from the standpoint of energy conservation. The industry is strongly requesting the development of such technology. PRIOR ART Several means have been attempted in the past to make the color of organic pigments in polymeric colorings more robust to light. For example, (1) making pigments themselves more robust against light, (2) incorporating ultraviolet absorbers into polymers to protect colored pigments from ultraviolet rays, and (3) making organic pigments less susceptible to light-induced damage. Measures include using autooxidation inhibitors to suppress decomposition. As a means of (1), products have been developed that improve the drawbacks of organic pigments such as light resistance, but as mentioned above, such high-grade organic pigments are very expensive.
With the exception of blue to green phthalocyanine types,
At present, it is used only in extremely limited fields and cannot be called a general-purpose pigment. Salicylic acid esters and their derivatives, benzophenone derivatives, benzotriazole derivatives, etc. are well known as ultraviolet absorbers for (2), and antioxidants for (3) include sterically hindered phenolic compounds, amine derivatives, Compounds having radical scavenging ability or peroxide decomposition ability such as imidazole derivatives are known. Although some of these compounds do exhibit the effect of preventing discoloration and fading of organic pigments, their effectiveness is small and cannot be said to be sufficient. In recent years, photobleaching of organic dyes such as dyes has mainly been caused by oxidation by active singlet oxygen generated through the involvement of the photosensitizing effect of the dye itself and oxygen in the air (triplet oxygen). It has been shown that this happens because of the To prevent photobleaching caused by this mechanism, conventional ultraviolet absorbers and autooxidant inhibitors have little effect, and compounds that have the effect of deactivating active singlet oxygen, which is the main cause of photobleaching, are needed. be effective. Compounds that have this effect include 1,4-diazabicyclo[2,2,2]octane and β-carotenes, but these have problems with sublimation and photostability. It is unsuitable for practical use, and a light fastener for organic pigment-colored products that exhibits comprehensively excellent effects for use with polymers has not yet been found. (Please refer to the Effects section below.) Summary of the Invention The present invention aims to provide a solution to the above problems, and achieves this objective by using an effective light fastening agent. This is what I am trying to do. Therefore, the light resistance stabilizer for polymer colored molding materials containing an organic pigment with improved light resistance related to photobleaching according to the present invention as a main colorant is selected from the following groups (a) to (d). It is characterized by containing at least one nickel salt. (a) A nickel salt of bisN-(n-alkyl)salicylaldimine represented by the general formula (). [In the formula (), R ¹ represents an n-alkyl group having 1 to 12 carbon atoms. ] (b) A substituted phenylsulfonic acid nickel salt represented by the general formula (). [In the formula (), R ² is a methyl group or a hydroxyl group, R ³
and R ⁴ represents a hydrogen atom or a methyl group. ] (iii) A nickel salt of 1,5-disulfonic acid naphthalene represented by the chemical formula (). (d) A nickel salt of 8-hydroxyquinoline-5-sulfonic acid represented by the chemical formula (). Effects The light resistance stabilizer for polymer colored molding materials of the present invention has the following effects:
Improvements have been made in the above points. The present applicant has completed an invention for preventing fading of paint by applying the compounds of group (a) to paint compositions (Japanese Patent Application No. 209501/1983). Furthermore, an example has been disclosed in which a compound related to group (a), a bis(N-n-dodecylsalicylaldimine) metal complex, is applied to prevent color fading of photographic film color images (Japanese Patent Laid-Open No. 56-99340
Publication No.). However, there have been reports of applications in which metal complexes related to groups (a) to (d) are added directly to polymer colored molding materials that use organic pigments as the main colorant for the purpose of increasing light fastness related to photobleaching. Yes, I can't find it yet. The present invention is based on basic research on the photobleaching mechanism and prevention mechanism of organic dyes.The photobleaching prevention effect of this nickel complex absorbs the activation energy of singlet oxygen, which is the main cause of photobleaching, and deactivates it. This invention was applied to colored polymer molding materials and succeeded in achieving the desired purpose. The stabilizer compound of the present invention, when contained in a small amount in a polymer, significantly increases the light fastness of a colored organic pigment, and by utilizing these properties, it can add value to colored polymers. It is possible to provide improvements that are advantageous in terms of industrial and resource saving by increasing the strength and durability. DETAILED DESCRIPTION OF THE INVENTION Stabilizer Compound The complex used as a stabilizer against photofading of a colored polymer in the present invention is a compound belonging to the above-mentioned groups (a) to (d). The compounds of group (a) are nickel salts having an n-alkyl group, but an n-dodecyl group is suitable from the viewpoint of compatibility with polymers. In the case of compounds of group (b), suitable substituted phenyl sulfonic acid nickel salts include R ² , R ³ and R ⁴
Mesitylene sulfonic acid nickel salt in which is a methyl group, and p-phenolsulfonic acid nickel salt in which R ² is a hydroxyl group and R ³ and R ⁴ are hydrogen atoms are exemplified. Groups (c) and (d) are nickel sulfonic acid salts of naphthalene and 8-hydroxyquinoline, respectively. All of these compounds are known,
Therefore, those synthesized by any method suitable for the purpose can be used. Next, representative compounds will be illustrated along with their melting points or decomposition points, but the invention is not limited to these. Compounds of group (a) bis(methylsalicylaldimine) nickel
(Melting point: 206°C) Bis(n-butylsalicylaldimine) nickel (Melting point: 141°C) Bis(n-dodecylsalicylaldimine)nickel (Melting point: 98°C) Compounds of group (b) Nickel mesitylene sulfonate
(Melting point 300℃ or higher) Nickel p-phenolsulfonate
(Melting point 300℃ or higher) Compound (c) Nickel salt of naphthalene 1,5-disulfonate
(Melting point: 300°C or higher) Compound of group (d) Nickel salt of 8-hydroxyquinoline-5-sulfonic acid (Melting point: 294.5°C) Among the examples of compounds in [groups (a) to (d)] above, other than commercially available products Prototypes were synthesized, and their structures were confirmed by elemental analysis and infrared absorption spectrum analysis. Use of stabilizer compound The "light-resistant stabilizer" of the present invention includes one or more metal complexes (stabilizer compounds) of the above [groups (a) to (d)] in a conventional polymer colored molding material. Obtained by blending. The amount of the stabilizer compound of the present invention added is generally in the range of 0.1 to 10% by weight based on the polymer component.
Particularly preferred is 0.3 to 2% by weight. When added to chlorosulfonated polyethylene, the amount added is preferably about 0.3 to 1.5% by weight, since the stabilizer compound tends to slightly delay or speed up the vulcanization time if added too much. Although some of the stabilizer compounds according to the present invention exhibit a slight green color, within the above-mentioned addition amount range, there is hardly any behavior accompanied by a change in the color tone of the colored pigment, and it can be used with confidence. can. In the present invention, these stabilizer compounds may be used in combination with other antioxidants and ultraviolet absorbers. Known antioxidants that help prevent discoloration include 2,6-di-t-butyl-4-methylphenol, 2,2'-methylenebis(4-methyl-6
-t-butylphenol), 4,4'-thiobis(3-methyl-6-t-butylphenol), 4,
Examples include phenol derivatives such as 4'-butylidene bis(6-t-butyl-m-cresol). By using these together, a greater effect of suppressing photobleaching may be obtained. Base polymer coloring composition As long as the stabilizer compound of the present invention is the above-mentioned specific metal complex and has an organic pigment as the main coloring agent, the base polymer coloring composition can be any suitable material. It can be something. In addition, the "base polymer coloring composition" here refers to
Refers to a polymer composition in which the stabilizer compound of the present invention is to be incorporated. Therefore, compositions containing known antioxidants such as the above-mentioned phenol derivatives, if necessary, are also considered to be a base polymer coloring composition as used in the present invention. Polymer compositions generally have very complex compositions, but the types of polymers to which the stable compounds of the present invention can be applied include polyolefins such as polyethylene, polypropylene, and polyvinyl chloride, polyurethanes, and synthetic Preferred examples include rubbers, but are not limited to these. The organic pigment used as the main coloring agent of the polymer coloring composition of the present invention is CIPigment Red 49.
In addition to red organic pigments such as CIPigment Red 3 (Toluidine Red), CIPigment Red 38 (Pyrazolone Red), CIPigment Red 48 (Watching Red), and CIPigment Orange 17 (Orange Lake), CI Solvent
Many organic pigments such as yellow and blue pigments such as No. 33 (quinoline yellow base) can be mentioned, and the present invention does not particularly limit the type of organic pigment to be used. However, since there are few suitable inorganic pigments with excellent light resistance, organic pigments are unavoidably used, and when applied to polymer compositions colored with red and yellow organic pigments, which are very frequently used. It can be said that the merit of the present invention is the greatest. In addition, inorganic pigments whose use has become difficult due to heavy metal pollution problems in recent years, such as yellow cadmium sulfide (CdS), which has been widely used for a long time, are subject to voluntary regulations due to the toxicity of cadmium. For polymer colored products using alternative organic pigments (for example, those with a quinophthalone skeleton), which were developed with the idea of replacing them with safe organic pigments even at the expense of light resistance, Great benefits can also be expected when the stabilizer compound of the present invention is applied. Suitable products for which the light stabilizer according to the present invention can be effectively used include colorfully colored corrugated boards that are directly exposed to sunlight outdoors, construction-related products such as rain gutters, roofing materials, and sealing materials, and laundry products. scissors, footwear, pipes, hoses, leisure supplies,
Exterior parts of vehicles such as automobiles, electric wires that are exposed to light indoors for long periods of time, home appliances, office supplies including office equipment, decorative boards, bathtubs, various large and small containers, escalator handrails, toys, and many other items. can be mentioned. Hereinafter, the effects of the present invention will be explained with reference to Examples, but the scope of the present invention is not limited to the embodiments described in the Examples. Examples Example 1 Chlorosulfonated polyethylene (Du Pont, USA)
100 parts by weight of Hypalon 40), 50 parts by weight of light calcium carbonate, 15 parts by weight of titanium white, 4 parts by weight of magnesia, 3 parts by weight of pentaerythritol, Noxeler TRA (Dipentamethylenethiuram tetrasulfide produced by Ouchi Shinko Chemical) Kogyo Co., Ltd. Product name) 2
Parts by weight, 4 parts by weight of yellow organic pigment of CI Solvent 33 (quinoline yellow base), various stabilizer compounds
0.5 parts by weight [However, 2,6-di-t-butyl-
4-Methylphenol (hereinafter abbreviated as "BHT")
1.0 parts by weight] was kneaded using a kneading roll machine using a conventional processing method. This kneaded material was vulcanized in a hot press at 160° C. for 20 minutes to obtain a sheet-like vulcanized product measuring 150×150×2 mm. A test piece of a predetermined size was cut from this sheet-like vulcanizate and exposed to light under the following conditions. Sunshine weather meter (blackboard temperature 63℃,
The results for 200 hours of exposure (no rainfall) are shown in Table-
As shown in 1. However, the color difference value (ΔE ^* _ab ) of the test piece before and after exposure to light is measured and calculated as [(Δ ^* _ab of the one with added stabilizer compound) / (ΔE ^* _ab of the standard one without additives)] ×
A value of 100 was calculated and compared as a measure of light fastness improvement ("fading ratio" shown in Tables 1 to 5). When the color difference value (ΔE ^* _ab = 28.5) of a standard vulcanizate that does not contain a stabilizer compound is used as the standard (100), the stabilizer compound of the present invention (example of the present invention) has a value of 9.8 to 54.3%. By adding the agent compound, the photofading of the colored pigment is suppressed to 1/10 to 1/2, and the light fastness is improved. In addition, the stabilizer compound (N8HQS) of the present invention and the phenolic antioxidant
An improvement in light fastness is also observed when used in combination with BHT (see Table 1). Example 2 The yellow pigment of Example 1 was replaced with 6 parts by weight of the red pigment of CI Pigment 38 (Pyrazolone Red B), and the light exposure time in a sunshine weather meter was changed.
Table 2 shows the results obtained using the same method except that the time was changed to 270 hours. From Table 2, it is recognized that the light fastness is improved by adding the stabilizer compound of the present invention. Example 3 100 parts by weight of polyether-based urethane prepolymer (Coronate 4095 manufactured by Nippon Polyurethane Industry Co., Ltd.), 6 parts by weight of CI Pigment 38, which is a red pigment, and 1.0 parts by weight of various stabilizer compounds (however, 1.0 parts by weight of BHT) ) are mixed at room temperature. The mixture is heated to 70°C and defoamed under reduced pressure. A curing agent (3,3'-dichloro-4,4'-diaminodiphenylmethane) heated and melted at 120°C was mixed into the defoamed mixture at 70°C in an amount of 17.6 parts by weight per 100 parts by weight of the prepolymer. Thereafter, it was poured into a mold and cured at 120°C for 3 hours to obtain a crosslinked urethane sheet measuring 150 x 150 x 2 mm. A test piece of a predetermined size was cut from this sheet and exposed to light for 270 hours in a sunshine weather meter (blackboard temperature 63°C, no rain).The results are shown in Table 3. From Table 3, it is recognized that the light fastness is improved by adding the stabilizer compound of the present invention. Example 4 Low density polyethylene (NUC manufactured by Nippon Unicar Co., Ltd.)
red pigment CI in 100 parts by weight of polyethylene)
6 parts by weight of Pigment 38 and 0.5 parts by weight of various stabilizer compounds were mixed and heated and molded using a hot press at 175°C for 5 minutes to produce a sheet of 150 x 150 x 2 mm. From this point on, the results of light exposure in the Sunshine weather meter using the same method as in Example 3 are shown in Table-
As shown in 4. Example 5 A sheet was prepared in the same manner as in Example 4 except that the low density polyethylene was changed to polyvinyl chloride (Vinicron 4000M manufactured by Mitsui Toatsu Chemical Co., Ltd.), and the results of light exposure are shown in Table 5. As shown. however,
The amount of BHT added was 1.0 part by weight. From Tables 4 and 5, it is recognized that the light fastness is improved by adding the stabilizer compound of the present invention.

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Claims (1)

[Scope of Claims] 1. A polymer colored molding material containing an organic pigment as a main coloring agent, characterized by comprising at least one nickel salt selected from the following groups (a) to (d). Light stabilizer. (a) A nickel salt of bisN-(n-alkyl)salicylaldimine represented by the general formula (). [In the formula (), R ¹ represents an n-alkyl group having 1 to 12 carbon atoms. ] (b) A substituted phenylsulfonic acid nickel salt represented by the general formula (). [In the formula (), R ² is a methyl group or a hydroxyl group, R ³
and R ⁴ represents a hydrogen atom or a methyl group. ] (iii) A nickel salt of 1,5-disulfonic acid naphthalene represented by the chemical formula (). (d) A nickel salt of 8-hydroxyquinoline-5-sulfonic acid represented by the chemical formula ().