JP2001303362A - Luminous polyvinyl alcohol-based yarn - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a yarn having high luminous fluorescent color brightness/ feeling and excellent visibility and decorativeness, to provide a method for producing the same and to obtain a yarn structure obtained from the yarn. SOLUTION: This luminous polyvinyl alcohol-based yarn contains a luminous inorganic compound.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a luminous polyvinyl alcohol (PVA) fiber and a method for producing the same, and a fiber structure using the fiber. Regarding excellent fiber.

[0002]

2. Description of the Related Art Fibers having a phosphorescent phosphor coated on the fiber surface have been known. However, such fibers have a problem that they have low durability because the coating layer is easily dropped off, and are inferior in feeling. there were. On the other hand, luminous phosphors blended with a luminous phosphor in a polymer that composes the fiber and melt-spun are also known. However, when performing the melt spinning method, a large amount of luminous phosphor is required to enhance visibility. In addition, there is a problem that mechanical performance is remarkably deteriorated due to the necessity of compounding, and fluffing or the like occurs due to inferior fibrillation processability, so that high-quality fibers cannot be obtained. When the amount of the phosphorescent phosphor added is reduced in order to suppress a decrease in mechanical performance or the like, visibility becomes insufficient. In order to solve the above problems, it has been proposed that a core component composed of a polymer containing a luminous phosphor is coated with another polymer to form a core-sheath type composite fiber. Since the amount of phosphorescent phosphor is easily increased, the amount of the phosphorescent phosphor cannot be increased so much. Further, since the phosphorescent phosphor is present only in the core component, the fluorescent coloring luminance and coloring properties are low.

[0003]

SUMMARY OF THE INVENTION It is an object of the present invention to provide a luminous fiber having good feeling and mechanical performance and good luminance and color development, a method for producing the same, and a fiber structure using the fiber. To provide body and paper.

[0004]

The present invention provides (1) a luminous polyvinyl alcohol fiber containing a luminous inorganic compound, (2) a luminous polyvinyl alcohol fiber containing a luminous inorganic compound and a pigment, 3) Luminescent polyvinyl alcohol-based fibers obtained by spinning a spinning dope containing at least a luminous inorganic compound and a vinyl alcohol-based polymer by any of a dry spinning method, a wet spinning method, and a dry-wet spinning method. (1) A fiber structure using the luminous polyvinyl alcohol-based fiber according to any one of (1) to (3), (5) the luminous polyvinyl alcohol-based fiber according to any one of (1) to (3). (6) a spinning dope containing at least a luminous inorganic compound and a vinyl alcohol-based polymer by a dry spinning method, a wet spinning method or a dry-wet spinning method. The method of manufacturing a phosphorescent polyvinyl alcohol fiber spinning in one of two ways law,
About.

[0005]

DETAILED DESCRIPTION OF THE INVENTION The PVA constituting the PVA fiber of the present invention is not particularly limited, and a modified PVA modified by another unit may be used. The average degree of polymerization of PVA is 300 from the viewpoint of handling properties of the spinning stock solution and fiber properties.
It is preferably at least 5,000 and at most 5,000, particularly preferably at least 500 and at most 3,000. The degree of saponification is preferably 96% or more and more preferably 99% or more from the viewpoint of water resistance and the like.

[0006] PVA fibers can be spun by a wet spinning method, a dry-wet spinning method, or a dry spinning method, so that breakage or the like does not easily occur, and thus, a fiber having a large amount of an inorganic compound and good coloring properties can be obtained. In the case of melt spinning, the fiber constituent resin is easily affected by hard inorganic fine particles because it is melted during spinning, and easily breaks and breaks, resulting in impaired spinnability and the mechanical properties of the resulting fiber. The quality is low. Also in the case of performing wet spinning or the like, it is difficult to produce a spinning dope in which the inorganic compound is easily aggregated and uniformly dispersed, so that thread breakage is likely to occur and fiber quality is likely to be impaired. However, in the present invention, since PVA is used as a fiber constituent resin, PVA is used.
Micellization by A is performed, whereby the uniform dispersibility of the inorganic compound and the stability of the spinning dope are remarkably improved, and a desired fiber can be obtained.

In some cases, conjugate spun fibers (core-sheath type,
(Side-by-side type, bonded type, etc.) or mixed spun fiber (sea-island structure fiber), etc., and a component other than the vinyl alcohol polymer may be blended as long as the effect of the present invention is not impaired. It is preferable to include a luminous chromogenic inorganic compound in the vicinity of the fiber surface from the viewpoint of obtaining high color development of the brightness. Specifically, at least a part of the chromogenic inorganic compound is present in the surface layer within 3 μm from the fiber surface. Preferably.

The phosphorescent inorganic compound used in the present invention is not particularly limited as long as it has phosphorescent fluorescent coloring.
For example, emitted by visible light irradiation including ultraviolet or ultraviolet component (e.g. D ₆₅ light by standard light source), moreover inorganic compound emitting afterglow over somewhat longer time after stopping the irradiation can be suitably used. Among them, those afterglow can be confirmed with the naked eye completely light brightness 200 lux D ₆₅ standard light source into left inorganic compound until afterglow is erased when left for 5 hours in the dark after the irradiation for 10 minutes in the dark Is preferably used. Since the afterglow is emitted after the irradiation is stopped as well as the irradiation with the ultraviolet light or the visible light containing the ultraviolet component, the decorativeness is high, and the presence or absence of forgery can be easily confirmed. Specifically, CaSrS: Bi (blue light emission), ZnS: Cu (green light emission), ZnCdS: Cu
Preferable examples include sulfide-based phosphors such as (yellow to orange light emission), and alkaline earth metal aluminates activated by europium and the like. In particular, an alkaline earth metal aluminate activated by europium or the like can be preferably used from the viewpoint of light resistance, chemical stability, persistence of the luminous effect and the like.
Examples of the alkaline earth metal constituting the luminous inorganic compound include strontium, barium, calcium and the like.Specifically, an alkaline earth metal salt and alumina, europium are sufficiently mixed, and if necessary, cerium or the like is used. And a mixture obtained by further adding and mixing the co-activator of the above and firing the mixture in a nitrogen-hydrogen mixed gas stream using an electric furnace. Of course, two or more fluorescent inorganic compounds may be used in combination as the luminous inorganic compound.

The larger the particle size of the luminous inorganic compound is, the higher the luminance of the luminous fluorescent color is, but the sedimentation stability and spinnability in the spinning solution are liable to decrease.
From the above, the average particle size is 20 μm or less, particularly 5 μm
It is preferable to set the value to 0.5 μm or less from the viewpoint of emission luminance.
m or more. In general, those having a small average particle size are not commercially available, and in some cases, it is preferable to reduce the average particle size by pulverizing an inorganic compound. The pulverization method is not particularly limited, and a suitable example is a method in which the inorganic compound is dispersed in water and then wet pulverized using a wet pulverizer (such as an attritor) having ceramic balls.

The proportion of the luminous inorganic compound contained in the fiber is 3 to 50% by mass / PVA, especially 5 to 45% by mass /
It is preferable to use PVA, more preferably 10 to 40% by mass / PVA. From the viewpoint of emission luminance, it is preferable to increase the amount of the inorganic compound. However, since the sedimentation and spinnability in the spinning dope are reduced, it is preferable to appropriately examine the amount according to the purpose. When the melt spinning method is adopted, the blending amount of the inorganic compound can be limited to at most about 8% by mass from the viewpoint of spinnability and the like, but in the present invention, a spinning method other than the melt spinning method can be adopted. Since PVA having an excellent effect of uniformly dispersing the inorganic compound is used, even if the amount of the inorganic compound is large, spinnability is hardly impaired, and a fiber having high emission luminance and excellent quality can be obtained.

A raw spinning solution may be prepared by blending a PVA-based resin and a luminous inorganic compound, and the fibers may be produced by a wet spinning method, a dry-wet spinning method or a dry spinning method. The mixing ratio of the PVA-based resin in the spinning dope is 8 to 30% by mass, especially 1%.
The content is preferably 0 to 20% by mass. If the PVA concentration is too low, the phosphorescent inorganic compound will settle, making it difficult to obtain desired fibers. As a solvent, water is preferably used from the viewpoint of spinnability, cost, and the like, but an organic solvent such as dimethyl sulfoxide may be used in some cases.

From the standpoint of suppressing the sedimentation of the luminous inorganic compound in the spinning dope and remarkably improving the uniform dispersibility, the dispersion water containing the luminous inorganic compound is added to the PVA immediately before the spinning nozzle.
It is preferable to employ a method in which the mixture is poured into the aqueous solution A, stirred immediately, and uniformly mixed with the spinning solution, and then discharged from the nozzle. By employing this method, fibers in which the luminous inorganic compound is uniformly dispersed can be produced more efficiently. It is preferable that the dispersion water is always settled by a stirrer until it is poured into the spinning solution. At this time, it is more preferable to add a dispersant for enhancing the uniform dispersibility of the inorganic compound to the dispersion water containing the luminous inorganic compound. The concentration of the luminous inorganic compound in the dispersed water is 20 from the viewpoint of uniform dispersibility and the like.
It is preferable that the concentration of the PVA solution is set to be higher than the desired concentration by about 3 to 5% because the addition of the dispersion water lowers the PVA concentration of the PVA aqueous solution.

From the viewpoint of suppressing aggregation of the luminous inorganic compound and improving dispersibility in water, it is preferable to add various surfactants to the spinning dope. In addition, by adding a surfactant, excellent effects such as prolongation of die life and improvement of stretchability of fiber can be obtained. The addition amount of the surfactant is preferably 20% by mass or less / spinning solution, particularly preferably 0.1 to 5% by mass.

A pigment may be added to the spinning dope to color the fibers in the visible light range. In particular, when a pigment having a color different from the luminescent color of the luminous inorganic compound is added, the color developed under visible light irradiation and the fluorescent color generated under ultraviolet irradiation can be changed. Excellent effects can be obtained. The pigment is not particularly limited as long as it can be stably dispersed in a spinning solution containing PVA and a luminous inorganic compound and can be stably spun. The amount of the pigment added is from 0.01 to 0.01 in terms of spinning stability and coloring properties.
It is preferably 5% by mass / PVA, particularly preferably 0.1 to 3% by mass. As the pigment, a wavelength of 400 nm or more and 780 n
Those that develop color under visible light of m or less are preferred.

The desired luminous PVA is obtained by spinning the spinning solution by a wet spinning method, a dry spinning method, or a dry-wet spinning method having an air gap filled with air or an inert gas between a spinning nozzle and a coagulation bath. A system fiber is obtained. From the viewpoint of spinning stability, it is more preferable to employ a wet spinning method. When performing wet spinning or dry-wet spinning, it is only necessary to immerse the yarn discharged from the nozzle in a coagulation bath. When the PVA aqueous solution is used as the spinning solution, for example, salts having a dehydrating ability such as sodium sulfate (Glauber's salt), ammonium sulfate, and sodium carbonate can be suitably used as the substance having a solidifying ability. The concentration of the coagulating liquid can be selected from 100 g / liter to a saturated concentration, but those having a concentration close to the saturated concentration can be suitably used because of their high dehydrating and coagulating ability. Coagulation bath concentration 20-70
° C, particularly preferably 30 to 50 ° C.

After the shinoshi is separated from the coagulation bath, it may be drawn to a predetermined fiber thickness according to a standard method. As a preferred method, after the bath is separated, the roller is stretched about 1 to 4 times, and then the same dehydration and coagulation capacity as the coagulation bath is obtained.
After performing wet heat stretching at a low temperature of 1 to 4 times in a bath of 0 to 100 ° C., drying, and stretching and heat treatment are performed as desired. If necessary, a formalization treatment or the like for improving water resistance can be performed.

The visibility of the colored fiber is greatly affected by the amount of the phosphorescent inorganic compound added, but is also greatly affected by the thickness of the fiber. The diameter of the fiber may be set as appropriate, but it is preferable to increase the diameter from the viewpoint of visibility.
Specifically, the diameter is about 20 to 30 μm or more, that is, 6d
tex or more is preferable. When the dry spinning method is adopted, not only fibers having a diameter of 25 μm or more can be produced, but also monofilaments having a diameter of 1 mm or more can be produced.
Further, when thin fibers are preferable, as in the case where the obtained fibers are made into paper, a wet spinning method or a dry-wet spinning method is preferably employed, and fibers having a diameter of about 5 to 60 μm are efficiently used. Can be manufactured A fiber having an excessively large fiber diameter is not preferable as a stock because of poor papermaking properties. In the melt spinning method, it is difficult to produce fibers with such fineness because the yarn is apt to break.

According to the present invention, there can be obtained a fiber which emits luminous fluorescent light with a high luminance and is excellent in quality and feeling and is free from agglutination. The fiber can be used for various purposes. For example, industrial materials, clothing, medical, agricultural materials, living materials, miscellaneous goods, etc., specifically, curtains,
Can be used for wallpaper, carpets (for emergency passages, etc.), raincoats, night work clothes, hats, banners, signs, lamp shades, artificial flowers, work ropes, tent ropes, counterfeit prevention paper such as securities paper, etc. However, it is suitable as anti-counterfeit paper.

Although the fiber of the present invention may be used as it is, it can be processed into any fiber structure. Specifically, cut fiber, yarn (spun yarn, filament yarn),
It can be processed into strings, ropes, fabrics (woven or knitted fabrics, nonwoven fabrics, etc.). At this time, it may be used in combination with fibers other than the PVA-based fibers of the present invention. The fibers that can be used in combination are not particularly limited, but may be other PVA fibers containing no dyeable fine particles, polyester fibers (including wholly aromatic polyester fibers), polyamide fibers, polyvinyl alcohol-ethylene copolymer. Fiber, cellulose fiber, cotton, hemp, and the like.

Among them, the fiber of the present invention is excellent in water dispersibility since it has high hydrophilicity and does not cause agglutination, and has a high adhesive effect, and thus is suitable as a stock. The fiber may be used as a stock to make a desired paper. At this time, general paper materials such as pulp (luminous PV
It is also possible to use together with a PVA-based fiber other than the A-based fiber), a binder fiber and the like, and obtain the obtained paper under ultraviolet irradiation or visible light irradiation containing an ultraviolet component without impairing the properties of conventional paper. A remarkable effect can be obtained from the fact that a high luminance and the ability to generate afterglow can be added under the light emitting device. 0.1 to 80% by mass of luminous PVA-based fiber from the point of anti-counterfeiting effect
/ Paper is preferably blended. The obtained paper is suitable as, for example, anti-counterfeit paper, decorative paper such as wallpaper, etc., and is particularly excellent as anti-counterfeit paper such as security paper.

[0021]

EXAMPLES The present invention will be described more specifically with reference to the following examples, but the present invention is not limited thereto. [Average particle size μm] 5,000 to 20,000 under electron microscope
Regarding the fine particles observed in the cross section of the fiber magnified 00 times, the diameter is measured when the fine particle shape is a perfect circle or a substantially circular shape, and the long diameter is measured when the fine particle shape is non-circular, and the average value of the diameter of the fine particles present in one cross section is calculated This is performed in five or more cross sections, and the average value is obtained. In the case of the fine particle dispersion, the particle size distribution is measured using a Microtrac particle size distribution measuring device, and the highest peak point particle size (MV value) is defined as the average particle size. [Inorganic compound content (based on PVA addition) mass%] The PVA-based fiber weighed in advance is dissolved in hot water, and the solution is filtered through a Teflon (registered trademark) membrane filter or an ultrafiltration membrane. The compound was separated and dried to determine the content.

[0022] After erasing [phosphorescent characteristics and afterglow characteristics] complete afterglow remaining in the sample and store a certain amount of the sample to about 15 hours dark, 10 minutes lightness 200 lux by D ₆₅ standard light source radiation Immediately after the stimulation, the state of light emission due to light storage in the dark was evaluated on the following four levels. Subsequently, the luminescence state due to the afterglow after being left in the dark for 5 hours from the irradiation was evaluated on the following four levels. A (very good): Sufficient light emission can be visually recognized with the naked eye. （(Good): Light emission can be visually recognized with the naked eye. Δ (Slightly poor): Light emission was barely visible with the naked eye. X (poor): Light emission cannot be confirmed with the naked eye.

Example 1 A phosphorescent inorganic compound of the structural formula Sr ₄ Al ₁₄ O ₂₅ : Eu, Dy which emits phosphorescent fluorescence under ultraviolet irradiation (“BG-30” manufactured by Nemoto Special Chemical Co., Ltd.)
OFF ”) 30 parts by mass, 7.5 parts by mass of a water dispersant (“ Demol P ”manufactured by Kao Corporation, pure content 20% by mass) with water 6
An aqueous dispersion of 30% by mass of the phosphorescent inorganic compound was added to 2.5 parts by mass. Next, the aqueous dispersion was wet-pulverized in a wet ball mill equipped with ceramic balls until the average particle size of the inorganic compound became about 1 μm.

An aqueous PVA solution having a PVA (degree of saponification: 99.9 mol%, viscosity-average degree of polymerization: 1700) concentration of 18% by mass.
Into 0 parts by mass, 18 parts by mass of the dispersion having a concentration of 30 parts by mass of the pulverized phosphorescent inorganic compound was injected and stirred, and the PVA concentration was 16% by mass.
Immediately after the spinning stock solution was prepared, it was discharged from a nozzle having 2000 holes into a coagulating solution having a temperature of 40 ° C. and a sodium sulfate concentration of 420 g / liter to form a shinoshino. Next, the obtained Itoshino is
La-stretching (drawing ratio 2 times), then 1.5-fold wet heat stretching in a saturated sodium sulfate bath at 95 ° C, and then drying at 160 ° C,
Further, it was heat-treated at 220 ° C. and wound up. The spinning property is good, and the yarn can be efficiently spun without substantially causing breakage,
The luminous inorganic compound was uniformly dispersed in the fiber.
Next, the glazing salt contained was washed in running water at 25 ° C. for 1 hour, and dried in a drier to obtain a single fiber fineness of 11 dtex.
Fibers were produced. The obtained fiber contains a luminous inorganic compound in an amount of 30% by mass / PVA, has no sticking or the like, has a good feel, and has a very good luminous property (◎) and a clear fluorescent blue color. Color was developed and the afterglow characteristics were also good (良好).

Example 2 PVA having a PVA (degree of saponification of 99.9 mol% and a viscosity average degree of polymerization of 1700) having a concentration of 18% by mass
Example 1 was repeated except that 12 parts by mass of a dispersion having a pulverized phosphorescent inorganic compound concentration of 30% by mass as in Example 1 was injected into 100 parts by mass of the aqueous solution A and stirred to prepare a spinning solution having a PVA concentration of 16% by mass. 11 dtex fiber was produced in the same manner as described above.
The spinnability was good and the fiber could be efficiently spun without substantial breakage or the like, and the obtained luminous inorganic compound was uniformly dispersed in the fiber. The obtained fiber contains 2 luminous inorganic compounds.
0% by mass / contains PVA, no sticking or the like is generated, the feeling is good, the phosphorescent properties are extremely good (良好), and a clear fluorescent blue color is generated, and the afterglow properties are also good (○). )Met.

[Example 3] PVA (degree of saponification: 99.9 mol%, viscosity average degree of polymerization: 1700) PV having a concentration of 18% by mass
Example 1 was repeated except that 6 parts by mass of the same dispersion of the pulverized phosphorescent inorganic compound as in Example 1 having a concentration of 30% by mass was injected into 100 parts by mass of the aqueous solution A and stirred to prepare a spinning solution having a PVA concentration of 16% by mass. 11 dtex fiber was produced in the same manner as described above.
The spinnability was good and the fiber could be efficiently spun without substantial breakage or the like, and the obtained luminous inorganic compound was uniformly dispersed in the fiber. The obtained fiber contains 1 luminous inorganic compound.
0% by mass / contains PVA, no sticking, etc., good feeling, good luminous properties (good)
And a clear fluorescent blue color was generated, and the afterglow characteristics were also good (良好).

Example 4 PVA (PV of 99.9 mol%, Viscosity Average Polymerization Degree 1700) PV of 18% by Mass
Into 100 parts by mass of the aqueous solution A, 18 parts by mass of the pulverized phosphorescent inorganic compound used in Example 1 having a concentration of 30% by mass and 0.5 part by mass of an orange pigment (manufactured by Dainichi Seika Kogyo Co., Ltd.) were injected. By stirring, a spinning solution having a PVA concentration of 16% by mass was prepared, and 11 dtex fibers were produced in the same manner as in Example 1.
The spinnability was good, the yarn could be efficiently spun without substantially causing breakage, and the luminous inorganic compound was uniformly dispersed in the fiber. The obtained fiber contains 30% by mass of the luminous inorganic compound.
/ PVA-containing, no sticking, etc., good feeling, colored orange under visible light, very good luminous properties (）), vivid fluorescent blue However, the afterglow characteristics were also good (○).

Comparative Example 1 A spinning dope was prepared and wet spinning was performed in the same manner as in Example 1 except that the luminous inorganic compound was not added to the spinning dope. The thickness of this thread Shino is 11dtex single yarn
In is a orange under visible light, be irradiated with D ₆₅ standard light does not emit phosphorescent light emission, phosphorescent characteristics and afterglow characteristics were both poor (×).

[Examples 5 to 8] Paper was produced using each of the PVA fibers obtained in Examples 1 to 4.
A PVA-based fiber containing no luminous inorganic compound (“VPB103 × 3” manufactured by Kuraray Co., Ltd., fineness: 1 dtex, fiber length: 3 mm) is dispersed in water at a temperature of 18 ° C. so as to be 45% by mass of the total mass of the sample. A sample fiber cut to a length of about 3 mm was added so as to be 40% by mass of the total mass of the sample, and a PVA binder fiber (“VPB105-1 × 3” manufactured by Kuraray Co., Ltd.) having a single fiber fineness of 1 d and a fiber length of 3
mm) to be 15% by mass of the total mass of the stock,
The slurry was uniformly stirred and mixed to prepare a slurry having a solid content concentration of 0.4% by mass. The slurry was supplied to a TAPPI paper machine to form a paper, and then dried using a cylinder dryer at 100 ° C. to produce a paper having a basis weight of 30 g / m ² . All of the fibers obtained in the examples had no sticking between the single fibers, and were excellent in water dispersibility, and high quality paper was obtained. Phosphorescent characteristics and afterglow characteristics due to both irradiation of D ₆₅ standard light also are those excellent like the fiber performance before papermaking, suitable as anti-counterfeit treated paper such as paper or security papers ornamental, such as wallpaper Was something.

Claims (6)

[Claims] 1. A luminous polyvinyl alcohol fiber containing a luminous inorganic compound. 2. A luminous polyvinyl alcohol fiber containing a luminous inorganic compound and a pigment. 3. A luminous polyvinyl alcohol fiber obtained by spinning a spinning solution containing at least a luminous inorganic compound and a vinyl alcohol polymer by a dry spinning method, a wet spinning method or a dry-wet spinning method. . 4. A fibrous structure comprising the luminous polyvinyl alcohol-based fiber according to claim 1. 5. A paper comprising the luminous polyvinyl alcohol-based fiber according to claim 1. 6. A method for producing a luminous polyvinyl alcohol-based fiber, comprising spinning an undiluted spinning solution containing at least a luminous inorganic compound and a vinyl alcohol-based polymer by a dry spinning method, a wet spinning method or a dry-wet spinning method. .