JPS5927402B2 - Method for producing colored cured phenolic fibers - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for producing colored cured phenolic fibers.

Generally, cured phenolic fibers are nonflammable and infusible.
As a new fiber, there are great expectations for its characteristics in clothing, interior goods, industrial applications, etc.

However, cured phenolic fibers have a denser fiber structure than other natural fibers or synthetic fibers, and do not have dye affinity groups, so it is extremely difficult to obtain dyed products from them. As one of the dyeing methods, a method for coloring raw material resin in which a pigment is mixed in advance during spinning of novolak resin is proposed in JP-A-50-158644.

However, in general, when dyes or pigments are mixed into the novolac resin during spinning and melt spinning is performed to obtain colored cured phenolic fibers after curing treatment, the agglomeration of the dyes or pigments during melt spinning may occur at the spinneret. This not only causes an increase in spinning pressure due to a clogged filter, and yarn breakage due to a clogged spinneret hole, which significantly reduces operability. Various disadvantages such as chemical decomposition of dyes or pigments or hue changes during the curing process, and furthermore, mixing of dyes or pigments can significantly reduce the yarn properties of the cured phenolic fiber as a product. It had

Furthermore, dyeing cured phenolic fibers black using conventional dyeing techniques is difficult to dye due to the dense fiber structure of cured phenolic fibers, and requires a large amount of dye, which is economically disadvantageous. Furthermore, even in the commonly used raw material resin coloring method using carbon black, it is necessary to use a large amount of carpon black in order to obtain black color, and the dispersibility of carpon black is poor, so melt spinning is difficult. Occasionally, the spinning filter clogged frequently and the spinneret holes clogged, which not only reduced operability but also caused a significant deterioration in the quality of the yarn produced.

The present inventors completed the present invention as a result of intensive research in order to eliminate the drawbacks in producing colored cured phenolic fibers by such raw material resin coloring method.

An object of the present invention is to provide a colored cured phenolic fiber with excellent spinnability and yarn properties. Another object of the present invention is to provide a black cured phenolic fiber having excellent spinnability, yarn properties, light resistance, and resistance to heat discoloration. Still another object is to provide a method for manufacturing such cured phenolic fibers or black cured phenolic fibers industrially easily and at low cost. That is, the present invention is characterized in that a novolak resin containing 1 to 15% (by weight) of at least one of the anthraquinone dyes represented by the general formula (1) is melt-spun and then hardened with an aldehyde. This is a method for producing colored cured phenolic fibers. General formula (where R: H1 alkyl, substituted alkyl, aryl,
It is obtained by melt-spinning a novolak resin containing a substituted aryl and at least one anthraquinone dye represented by structural formulas (2) and (3) in an amount of 1 to 15% (by weight), followed by curing treatment with an aldehyde. This method of producing colored cured phenolic fibers is characterized by subjecting the cured phenolic fibers to heat treatment at a temperature of at least 120° C. for 5 minutes or more.

Structural formula Generally speaking, the raw material resin coloring method in which dyes or pigments are mixed during spinning may cause clogging of the filter or the nozzle hole during spinning, or chemical decomposition of the dye or pigment during the curing process. However, in the method for producing colored cured phenolic fibers according to the present invention, , has good spinnability, no change in dye during curing treatment, and excellent yarn properties of the product, and also has the above structural formula (2). By subjecting the novolac resin fiber containing the anthraquinone dye shown in (3) to heat treatment after curing, it is colored black with excellent light resistance and heat discoloration resistance as well as excellent properties above. This is a completely groundbreaking invention that makes it possible to obtain cured phenolic fibers.

The novolak resin applied to the present invention generally refers to a novolak resin obtained by adding phenols in excess of aldehydes and polycondensing them in the presence of an acid catalyst, and usually has a molecular weight of 2000 or less. is used, but its molecular weight is not particularly limited.

Furthermore, the novolak resin referred to herein does not necessarily have to be a linear polymer, and may include partially branched polymers or crosslinked polymers. Further, the novolak resin containing the anthraquinone dye may be melt-spun using the novolak resin alone as the resin component, but the novolac resin may be melt-spun using 95 to 60% (by weight) of the novolac resin and 5% of the thermoplastic resin other than the novolak resin. ~40% (by weight) may be mixed and melt-spun.

Examples of the thermoplastic resin include 6-nylon, 7-nylon, 9-nylon, 11-nylon, 12-nylon, 6,6-nylon, 6,10-nylon, general formula ℃ 6T denoted by n
Nylon, and general formula
Polyamides such as 11T nylon represented by H22nan, copolymers containing these as main components, and polyester polymers such as polymethylene terephthalate, polyethylene terephthalate, polybutylene terephthalate, polyethylene oxyterephthalate, and polycyclohexylene terephthalate. Polyolefin polymers such as polyethylene, polypropylene, polystyrene, polyvinylidene chloride, polyvinyl chloride and copolymers thereof, and copolymers thereof, and the above-mentioned thermoplastic resins include A mixture of these may be used.

The anthraquinone dyes applicable to the present invention are those represented by the general formula (1) above, and among them, the anthraquinone dyes represented by the structural formula or have particularly good spinnability and yarn properties. preferable.

In the method of the present invention, the anthraquinone dye represented by the general formula (1) is used in an amount of 1 to 15% based on the novolak resin.
It is preferably contained in an amount of 3 to 10% (by weight).

If the content is less than 1% (by weight), a long kneading time is required to uniformly disperse the dye, which is not only economically disadvantageous, but also tends to cause coloring spots, reducing the commercial value. decrease. Further, if the amount exceeds 15% (by weight), yarn breakage will occur frequently during melt spinning, and the quality of the yarn will deteriorate after the curing treatment. Further, in order to change the hue within the above range, the above anthraquinone dyes may be used in combination.

In the present invention, the above-mentioned anthraquinone dye is contained in a novolak resin, and after melt spinning, a curing treatment is performed with an aldehyde.

The above-mentioned method of mixing the anthraquinone dye with the novolak resin includes a method in which the anthraquinone dye is uniformly mixed during or after polymerization during the production of the novolak resin, and a method in which the mixture is uniformly mixed during melt spinning and then supplied to a melter 1, a grid melter 1, an extruder 1, etc. Alternatively, a master pellet method may be used in which novolak resin pellets containing a high content of anthraquinone dye are prepared in advance, and this is mixed with novolak resin pellets containing no dye and melt-spun. This is not limited to this.

Examples of the curing treatment include a method of curing with an acidic catalyst and an aldehyde, or a method of pre-curing with an acidic catalyst and an aldehyde and then further curing with a basic catalyst and an aldehyde.

Examples of acidic catalysts include inorganic and organic acids such as hydrochloric acid, sulfuric acid, phosphoric acid, oxalic acid, and para-toluenesulfonic acid; examples of basic catalysts include ammonia, potassium hydroxide, calcium hydroxide, etc. It will be done.
Examples of aldehydes used in the curing treatment include formaldehyde, paraformaldehyde, benzaldehyde, glyoxal, and hexamethylenetetramine, with formaldehyde being particularly preferred. ,
It can be easily obtained by melt-spinning a novolak resin containing an anthraquinone dye of structural formula (2) or (3), curing with aldehydes, and further heat-treating.

Such heat treatment needs to be carried out at a temperature of at least 120° C. for 5 minutes or more. When heat treatment is performed at a temperature lower than 120°C, it is difficult to obtain cured phenolic fibers colored black, which is one aspect of the present invention, and the light resistance and heat discoloration resistance are also insufficient. It is also economically disadvantageous since it requires processing.

The heat treatment temperature is preferably in the range of 130 to 230°C, more preferably in the range of 140 to 200°C. Within this range, color spots do not occur, and a black color with particularly good light resistance and heat discoloration resistance is produced. A colored cured phenolic fiber is obtained.

In addition, if the heat treatment time is less than 5 minutes, not only will the light resistance and heat discoloration resistance be insufficient, but also color spots will occur, resulting in completely black cured phenolic fibers.
Full 1ha 6i- 1088β day flute) FL7 or 10
~120 minutes. Raising the heat treatment temperature too high or carrying out the treatment for a long time is economically disadvantageous, and not only does the quality of the yarn tend to deteriorate, but also the vividness of the hue is lost. Furthermore, if the heat treatment conditions are too severe, the light resistance effect tends to deteriorate, which is not preferable. The object of the present invention can be easily achieved by appropriately selecting the heat treatment temperature and heat treatment time.
Most preferred is a heat treatment at a temperature of 00°C for 10-120 minutes.

The heat treatment according to the method of the present invention may be carried out by selecting the above-mentioned heat treatment temperature and time using, for example, a hot air circulation type rotary dryer, a net type dryer, etc. Furthermore, it may also be carried out by a steam heat treatment method using steam or the like. It is not particularly limited to this.

When obtaining colored cured phenolic fibers according to the method of the present invention, a plasticizer,
Inorganic or organic substances such as flame-retardant additives may be added, and when mixing the thermoplastic resin, the above-mentioned substances may be added.

When producing hardened phenolic fibers colored black according to the method of the present invention, the hardened fibers are subjected to oil or resin treatment such as oil treatment, softening treatment, antistatic treatment, etc. before heat treatment. may be used, and is not particularly limited to this.

Thus, by melt-spinning the novolak resin containing the anthraquinone dye represented by the general formula (1) according to the method of the present invention and then curing it with an aldehyde, it is possible to prevent the filter in the spinneret from becoming clogged during melt-spinning. There is no increase in spinning pressure caused by the spinning process, and there is no occurrence of yarn breakage due to clogging of the nozzle hole, so the operability is significantly improved, and there is no change in hue and is stable even in the presence of acidic or basic catalysts during curing treatment. Furthermore, colored cured phenolic fibers with excellent yarn properties can be obtained. In addition, after melt-spinning a novolak resin containing an anthraquinone dye of structural formula (2) or (3), curing treatment with aldehydes and further heat treatment improves spinnability and yarn properties. A cured phenolic fiber colored black can be obtained which has not only good properties but also excellent light resistance and heat discoloration resistance.

Furthermore, the raw material resin coloring method according to the present invention is economically very advantageous compared to ordinary dip dyeing methods, pigment dyeing methods, etc., and in the manufacturing process for obtaining colored cured phenolic fibers. The contribution of the present invention to product quality, economy, etc. is immeasurable. Furthermore, the colored cured phenolic fiber according to the method of the present invention can be easily produced industrially without impairing the properties of the sulfurized phenolic fiber such as infusibility, nonflammability, and chemical resistance. It is.

Next, examples will be described in detail, but the present invention is not limited thereto.

The methods for measuring light resistance and thermochromic resistance in Examples are as follows.

Light resistance: Fade-o-meter - JISLO after 20 hours of irradiation
842 (1971).

Heat discoloration resistance: Treated in a hot air circulation dryer at a temperature of 80°C for 24 hours, chromaticity coordinates under a standard C light source were determined from the samples before and after the treatment, and color difference in NBS units was measured.
Example 1 Anthraquinone dyes having the structural formula according to the present invention were added to a novolak resin having a number average molecular weight of 820 in varying amounts, and were prepared using a spinning device using a grid melter with a nozzle hole diameter of 0.3 m7fLφ and a number of holes of 50. Melt spinning was performed using a Hall spinneret at a spinning speed of 500 m/min, and the temperature was further raised from room temperature to 95°C in 120 minutes using a mixed aqueous solution of 17% (by weight) hydrochloric acid and 12% (by weight) formaldehyde. After that, it was held at that temperature for 150 minutes to perform a curing treatment, and after washing with hot water, it was treated with a 50% neutral methanol aqueous solution to obtain a cured phenolic fiber colored in vivid red with each single yarn fineness of 3.0 denier. I got it.

Spinning pressure after 240 hours of continuous spinning under the same filter conditions during melt spinning depending on the amount of dye added, number of yarn breaks just below the spinneret, and yarn quality characteristics after curing treatment F2 Texture 1 Main 7f-J
As is clear from the above results, the anthraquinone dye according to the present invention was added to the novolak resin at 1 to 1
It can be seen that by containing 5% (by weight), there is almost no increase in spinning pressure or yarn breakage, and furthermore, the yarn properties after curing treatment are excellent.

In addition, considering the characteristics of the fiber quality and the occurrence of colored spots, it is 3 to 10%.
It turns out that the range of (weight) is preferable. In addition, compared to the dye-free product, the colored cured phenolic fiber has
There was no difference in non-fusibility and non-flammability. Example 2 A novolak resin with a number average molecular weight of 790 was prepared with the following structural formula (I
) to 30% (by weight) were preliminarily contained and granulated to obtain colored novolak resin pellets.

Structural Formula The above colored pellets were mixed with additive-free pellets and fed into a 20 mmφ extruder so that the above dyes accounted for 6% (by weight) of the novolak resin, and the nozzle diameter was 0.25 m.
Spinning speed 600 m/m using a spindle with mφ and 120 holes.
Melt spinning was carried out for 1 minute.

Further, a curing treatment was performed in the same manner as in Example 1 to obtain colored cured phenolic fibers each having a single fiber fineness of 2.0 denier. Table 2 shows the spinning pressure fluctuation value during spinning for 120 hours, the number of yarn breakages, the hue after curing treatment, and the yarn quality characteristics during spinning during the production of each colored cured phenolic fiber.

As is clear from the above results, by containing the anthraquinone dyes (1) to (5) according to the present invention and performing curing treatment after melt spinning, the spinning pressure fluctuation value during melt spinning is lower than that without additives. It can be seen that the yarn is smaller in approximately the same range as compared to the above, the number of yarn breakages due to the clogging of the nozzle hole is lower, and furthermore, the hue after the curing treatment is clearer and the yarn quality characteristics are also better.

When anthraquinone dyes other than the general formula (1) such as azo dye M-(t) or structural formula (to) were used, the color changed during the curing process.

After the curing treatment, there was almost no difference in the infusible, nonflammable properties and chemical resistance of each colored cured phenolic fiber compared to additive-free products.

Example 3 Using the colored cured phenolic fiber containing the anthraquinone dye of the structural formula ~ obtained in Example 2, the heat treatment temperature was changed in a hot air circulation dryer, and the heat treatment time was 40 minutes. A heat treatment was performed for 120 minutes to obtain a cured phenolic fiber colored black.

Table 3 shows the presence or absence of color spots and the results of the light fastness test for each sample.

In the above heat treatment, although cured phenolic fibers colored black were obtained under each heat treatment temperature condition of 120°C or higher, color spots occurred when heat treated at 250°C. Moreover, the quality of the fibers was significantly reduced to 1.2 y/d or less in strength and 20% or less in elongation, and furthermore, when the heat treatment conditions became severe, the light resistance tended to decrease.

On the other hand, under other heat treatment conditions, the strength was 1.3 to 1.
67/d elongation was maintained at 25-35%. As is clear from the above results, it can be seen that by performing heat treatment at a temperature of 120° C. or higher, cured phenolic fibers colored black with excellent light resistance can be obtained. Also, considering the decrease in strength and elongation of the fibers and the occurrence of color spots, in the above heat treatment in the temperature range of 130 to 230 °C, 24 °C under each heat treatment temperature condition.
It can be seen that in the 0-minute heat treatment, the curing heat treatment conditions colored black are preferable. In addition, as a result of the heat discoloration test of each of the above-mentioned black colored cured phenolic fibers, the number of NBS units was significantly improved in the range of 2.8 to 5.9, and the non-fusible and non-flammable properties of each sample were significantly improved. No difference was observed when compared with a product without dye additives.

Example 4 Similar to Example 3, structural formula 5(5) obtained in Example 2
Colored cured phenolic fibers containing anthraquinone dyes were heat treated using a hot air circulation rotary dryer at heat treatment temperatures of 140°C and 180°C with varying heat treatment times.

Table 4 shows the results of the light fastness test and the presence or absence of color spots on each sample. Although enol-based fibers were obtained, the quality of the fibers showed a significant decrease in strength of less than 1.2 y/d and elongation of less than 20%, and the light resistance also tended to decrease.

Also, under other conditions, the strength is 1.3 to 1.67/
d elongation was maintained at 25-37%. Furthermore, the fibers obtained by heat treatment for 5 minutes or more were completely black. As is clear from the above results, under each heat treatment temperature condition, heat treatment for 5 minutes or more improves light resistance, and also improves the presence of color spots and decreases in fiber strength and elongation. Taking this into account, it can be seen that heat treatment conditions of 5 to 180 minutes are preferable.

It should be noted that no difference was observed in the infusible and nonflammable properties and chemical resistance of the cured phenolic fibers colored black obtained by each of the above heat treatments compared to unheat-treated products and dye-free products. In addition, as a result of the heat discoloration resistance test of each of the above-mentioned black phenolic fibers, the NBS units were significantly improved in the range of 2.8 to 6.9.

Example 6 83% (by weight) novolak resin with a number average molecular weight of 880,
A mixture consisting of 10% (by weight) of 6 nylon and 7% (by weight) of anthraquinone dye of the following structural formula according to the present invention was melt-spun according to the method of Example 1, and an additional 17%
(by weight) of hydrochloric acid and 13% (by weight) of formaldehyde in a mixed aqueous solution, the temperature was raised from room temperature to 95°C in 90 minutes, held at that temperature for 120 minutes, washed with hot water, and further increased to 2.5% (by weight). A hardening treatment was performed at 90° C. for 60 minutes in a mixed aqueous solution of (by weight) ammonia and 26% (by weight) formaldehyde.

Further treatment was performed with a 50% neutral methanol aqueous solution to obtain a hardened phenolic fiber colored dark blue with a single yarn fineness of 3 denier strength 1.437/d elongation 46%. The fibers were heat-treated at 160° C. for 40 minutes in a hot air circulating band dryer to obtain cured phenolic fibers colored black.

Regarding the above black colored cured phenolic fiber,
As a result of light resistance and heat discoloration tests, the untreated fiber had a light resistance of grade 3 to 4 and heat discoloration resistance of 3.5, compared to the untreated fiber's light resistance of grade 1 and heat discoloration resistance of 22 (NBS units). I got it.

Furthermore, there was almost no yarn breakage during spinning, and no difference in yarn properties or non-fusibility and non-flammability was observed before and after heat treatment.

Claims (1)

[Scope of Claims] 1 A novolak resin containing 1 to 15% (by weight) of at least one anthraquinone dye represented by the general formula (1) is melt-spun and then hardened with an aldehyde. A method for producing colored cured phenolic fibers. General formulas▲Mathematical formulas, chemical formulas, tables, etc.▼・・・・・・・・・
...(1) (However, R:H) alkyl, substituted alkyl, aryl, substituted aryl X:H, OH Y:H, halogen). 2. The manufacturing method according to claim 1, wherein the anthraquinone dye is represented by structural formula (2) or (3). Structural formula▲There are mathematical formulas, chemical formulas, tables, etc.▼・・・・・・
・・・・・・(2)▲There are mathematical formulas, chemical formulas, tables, etc.▼
(3) 3. The manufacturing method according to claim 1 or 2, which contains 3 to 10% (by weight) of anthraquinone dye. 4 Novolac resin is 95-60% novolac resin (
weight) and thermoplastic resins other than novolac resins 5-40%
(by weight). 5 Obtained by melt-spinning a novolak resin containing 1 to 15% (by weight) of at least one of the anthraquinone dyes represented by structural formulas (2) and (3), and then curing with aldehydes. A method for producing colored cured phenolic fibers, which comprises heat-treating the cured phenolic fibers at a temperature of at least 120° C. for 5 minutes or more. ▲There are mathematical formulas, chemical formulas, tables, etc.▼・・・・・・・・・(
2) ▲There are mathematical formulas, chemical formulas, tables, etc.▼・・・・・・・・・
-(3)6 The manufacturing method according to claim 5, which contains 3 to 10% (by weight) of anthraquinone dye. 7. The manufacturing method according to claim 5 or 6, wherein the heat treatment is performed at a temperature of 130 to 230°C. 8 Claim 5 in which heat treatment is performed for 5 to 180 minutes
6. The manufacturing method according to item 6 or 7. 9. The manufacturing method according to claim 7 or 8, wherein the heat treatment is performed at a temperature of 140 to 200°C for 10 to 120 minutes. 10 Novolac resin is 95-60% novolac resin
(weight) and thermoplastic resin other than novolac resin 5 to 40
% (weight).