JP3134279B2 - Colorant for polyester resin - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a colorant mainly used for coloring polyethylene terephthalate resin, which is used as a material for various molded articles such as fibers, films and three-dimensional molded articles. The present invention relates to a black polyester colorant having an improved black hue by using a resin, a polybutylene terephthalate resin, and carbon black.

[0002]

2. Description of the Related Art Conventionally, black hue has been used in terms of hue comparison judgment such as reddish, bluish, dark, thin, deep, lacking in depth, etc., and subtle hue judgment has been made. . Above all, expressions such as jet black, deep black, formal black and crow's wet feather color are used as excellent deep black, but in general expression it is "deep black", The demands are strong.

In a stock solution coloring method for a polyethylene terephthalate-based resin using a master batch containing carbon black, carbon black has a fine primary particle size, and the more finely dispersed in the polyethylene terephthalate-based resin, A deep black color is obtained. However, since carbon black having fine primary particles has strong cohesiveness, it is difficult to obtain fine and uniform dispersion in the resin. For this reason, carbon black tends to give a molded product a reddish tint, thereby giving the product an inexpensive image, and despite being excellent in other physical properties, its use is disliked.

As means for improving the dispersion of carbon black, a method of using polyglycol as a dispersant (Japanese Patent Publication No. 44-22744) and a method of adjusting the redness of carbon black with copper phthalocyanine green (Japanese Patent Publication No. 55-40619) and the like. However, in these methods, the coloring fastness of the polyethylene terephthalate-based resin molded article is reduced due to the influence of the dispersant and phthalocyanine green, and the use of the colored polyester-based resin is actually limited. .

[0005]

An object of the present invention is to provide a black colorant for obtaining a polyethylene terephthalate resin molded article having a deep black color without lowering the color fastness.

[0006]

The present inventors have made intensive studies to solve the above-mentioned problems, and as a result, as a resin system for distributing and containing carbon black in a colorant, a combination of polyethylene terephthalate resin and polybutylene terephthalate resin. The use was found to have a carbon black dispersing effect, and an undiluted colored yarn (hereinafter sometimes referred to as a so-called dyed yarn) was experimentally produced and a hue evaluation was carried out. As a result, a deep black was obtained. Furthermore, in a spinning test using a master batch having a high carbon black content, a result was obtained in which the deflocculability of the master batch was improved.

That is, the present invention is a coloring agent for polyethylene terephthalate, comprising a polyethylene terephthalate resin (A), a polybutylene terephthalate resin (B) and carbon black (C).

A typical example of the polyethylene terephthalate resin (A) used in the present invention is a resin obtained by polycondensation through a transesterification reaction or an esterification reaction using dimethyl terephthalate or terephthalic acid and ethylene glycol as starting materials. (Hereinafter sometimes referred to as PET), but any polymer having ethylene terephthalate units as a main component may be used.

The polybutylene terephthalate resin (B) is, for example, a resin called polybutylene terephthalate (polytetramethylene terephthalate) obtained by polycondensation of 1,4-butanediol with terephthalic acid or dimethyl terephthalate. As a representative example (hereinafter sometimes referred to as PBT), any polymer may be used as long as it is mainly composed of a butylene terephthalate unit.

In the present invention, the ratio (A) / (B) of the resin (A) to the resin (B) is usually 99/1.
２０20/80. Preferably, 97/3 to 3
5/65, especially in the range 97/3 to 75/25.

As the carbon black in the present invention, various types of carbon black can be used, and usually those having an average primary particle diameter of 10 to 60 μm are used. Preferably, it is in the range of 14 to 40 mμ.

The proportion of carbon black used in the present invention is the sum of (A) + (B) of resin (A) and resin (B).
) In the range of 2 to 80 parts by weight per 100 parts by weight,
Preferably it is in the range of 2 to 55 parts by weight.

The colorant in the present invention is prepared by mixing the resin (A) and the carbon black and then adding the resin (B), mixing the resin (B) and the carbon black and then adding the resin (A), A) The same desired effect can be obtained by any of the methods of simultaneously mixing (B) and carbon black.

The colorant of the present invention may contain, for example, pigments other than carbon black, flame retardants and other various additives, if desired, in addition to these essential components. It is.

Further, the coloring agent of the present invention can be used for various thermoplastic polyester resins, especially PET, PB
It is suitably used for polyethylene terephthalate-based resins such as T and polybutylene terephthalate-based resins, and polyethylene terephthalate-based resins are particularly preferred.

The colorant for polyester resin according to the present invention may be used by a conventional method of using a masterbatch for a thermoplastic polyester resin. For example, in the case of coloring a polyester fiber, 2 to 10 parts by weight of the coloring agent according to the present invention is blended with 100 parts by weight of PET to be colored, and the mixture is melt-extruded according to a conventional method to obtain a fiber. A colored fiber is obtained. This fiber has an excellent black hue and can be used for clothing such as school uniforms, fishing nets, ropes and other industrial materials, and others.

[0017]

The molded article colored by the colorant of the present invention has a deep black color because the carbon black particles are finely dispersed in the polyester resin constituting the colorant and the dissolution of the colorant. It seems that the adhesiveness was improved and the function of facilitating the dispersion of the carbon black in the polyester resin to be colored occurred, and particularly good results were obtained in the polyethylene terephthalate resin.

[0018]

The present invention will be more specifically described below with reference to examples, comparative examples and measurement examples. The part in each example is
It is based on weight, and PET is “R” manufactured by Toyobo.
D-500 ”and PBT from Mitsubishi Kasei (currently Mitsubishi Chemical).
"Novadur 5008" manufactured by Tokai Carbon Co., Ltd. and "Seast-6" manufactured by Tokai Carbon Co., Ltd. were used as carbon black.

Example 1 After 90 parts of PET, 10 parts of PBT and 25 parts of carbon black were mixed, the mixture was dried in a drier at 170 ° C. for 5 hours and melt-extruded to obtain a master batch. After mixing 10 parts of the master batch with 90 parts of a polyethylene terephthalate resin for dilution (to be colored, the same applies hereinafter), the mixture is spun and stretched to obtain an original yarn (hereinafter referred to as original yarn-a). .

Comparative Example 1 After mixing 100 parts of PET and 25 parts of carbon black,
It was dried in a dryer at 70 ° C. for 5 hours, and was melt-extruded to obtain a master batch. After mixing 10 parts of the master batch and 90 parts of polyethylene terephthalate resin for dilution, the mixture was spun and stretched according to a conventional method to obtain an original yarn (hereinafter referred to as original yarn-p).

Comparative Example 2 After mixing 100 parts of PBT and 25 parts of carbon black,
It was dried in a dryer at 70 ° C. for 5 hours, and was melt-extruded to obtain a master batch. After mixing 10 parts of the master batch with 90 parts of polyethylene terephthalate resin for dilution, the mixture was spun and stretched according to a conventional method to obtain an original yarn (hereinafter referred to as original yarn-q
).

Measurement Example 1 Colorimetry was performed by a spectrophotometer for comparing the hues of the original yarns a, p, and q, and the results were represented by L value, a value, and b value.
It is shown in Table 1. Those with a small L value are excellent in blackness,
The smaller the a-value and the b-value, the deeper the hue is and the deeper the black.

Examples 2, 3, 4, and 5 The amount of carbon black was 25 parts (PET (A) + PBT).
(B)) The mixing ratio of a total of 100 parts was 99/1, 9 respectively.
7/3, 80/20, 35/65, the original yarn was obtained in accordance with the prescription of Example 1 (hereinafter, the original yarn-b, respectively).
c, d, and e).

Measurement Example 2 For comparison of hues, the above-mentioned yarns-b, c, d, and e were measured by the above-mentioned method, and the results are shown in Table 1.

Example 6 After mixing 10 parts of PBT, 90 parts of PET and 43 parts of carbon black, the mixture was dried in a drier at 170 ° C. for 5 hours and melt-extruded to obtain a master batch. 6.7 parts of the master batch and polyethylene terephthalate resin for dilution 9
After mixing 3.3 parts, the mixture was spun and drawn according to a conventional method to obtain an original yarn (hereinafter referred to as an original yarn-f).

Example 7 After mixing 20 parts by weight of PBT, 80 parts by weight of PET and 43 parts by weight of carbon black, the mixture was dried in a dryer at 170 ° C. for 5 hours and melt-extruded to obtain a master batch. After mixing 6.7 parts of the masterbatch and 93.3 parts of polyethylene terephthalate resin for dilution, the mixture was spun and stretched according to a conventional method to obtain an original yarn (hereinafter referred to as original yarn-g).

Measurement Example 3 For comparison of hues, the above-mentioned yarns-f and g were also measured by the above-mentioned method, and the results are shown in Table 1.

Comparative Example 3 After mixing 100 parts of PET and 43 parts of carbon black, 1
It was dried in a dryer at 70 ° C. for 5 hours and melt-extruded to obtain a master batch. After mixing 6.7 parts by weight of the master batch and 93.3 parts of a polyethylene terephthalate resin for dilution, the mixture was spun according to a conventional method. However, the yarn was broken at the time of drawing, and the drawing operation was difficult, and a protrusion was observed on the surface of the obtained spun yarn (hereinafter referred to as spun yarn-r).

Comparative Example 4 After mixing 100 parts of PBT and 43 parts of carbon black,
It was dried in a dryer at 70 ° C. for 5 hours, and was melt-extruded to obtain a master batch. After mixing 6.7 parts of the master batch with 93.3 parts of polyethylene terephthalate resin for dilution, the mixture was spun according to a conventional method. However, the yarn was broken at the time of drawing, and the drawing operation was difficult, and a protrusion was observed on the surface of the obtained spun yarn (hereinafter referred to as spun yarn-s).

Measurement Example 4 As a result of observing the original yarns -r and s with an optical microscope, it was found that the protrusions were caused by unraveled materials of the master batch. For the uncoated yarns -a to g, p, and q, no unraveled material of the master batch and no protrusions on the yarn surface were confirmed.

[0031]

[Table 1]

[0032]

The coloring agent of the present invention can be used for polyester resin molded articles requiring a deep black color.
Typically, it can be used for clothing such as school uniforms and formal clothes, industrial materials such as fishing nets, ropes and carpets, and light shielding sheets. Comparing the masterbatch according to the present invention with the masterbatch according to the present invention, the masterbatch according to the present invention requires only a small amount to obtain the same concentration. Thereby, the processability of the colored molded product is improved, and the reduction of material loss can contribute to the reduction of industrial waste.

Claims (7)

(57) [Claims] 1. A polyester resin colorant comprising a polyethylene terephthalate resin (A), a polybutylene terephthalate resin (B), and carbon black (C). 2. The weight ratio (A) / (B) of the resin (A) to the resin (B) is from 97/3 to 35/65.
The coloring agent as described above. 3. The weight ratio (A) / (B) is 97/3 to 75.
The coloring agent according to claim 2, wherein the ratio is / 25. 4. The use ratio of carbon black (C) is as follows:
Total of resin (A) and resin (B) ((A) + (B)) 1
The amount is 2 to 80 parts by weight with respect to 00 parts by weight.
Or the coloring agent of 3. 5. The use ratio of carbon black (C) is as follows:
The colorant according to claim 4, wherein the amount is 20 to 55 parts by weight. 6. The colorant according to claim 1, which is a colorant for a polyethylene terephthalate resin. 7. A colorant for undiluted colored fibers.
The coloring agent according to any one of Items 1 to 6, above.