KR20210070106A - Fiber type color changeable gas sensor and article including the same - Google Patents

Abstract

Provided is a fiber-type color change gas sensor and an article including the same, comprising: fibers having a composite cross-sectional structure or a heterogeneous cross-sectional structure; and a dye that is located on at least one of the surface and the inside of the fiber, and shows a color change when exposed to acidic or basic gas.

Description

Fiber type color changeable gas sensor and article including the same}

The present invention relates to a fiber-type color change gas sensor and an article including the same, and specifically, a fiber-type color change gas sensor that allows an operator to immediately recognize a dangerous situation by directly observing a color change with the eyes, and an article comprising the same is about

Recently, safety accidents occurring in chemical-related industrial sites and casualties due to chemical gas leaks and explosions are continuously increasing, and accordingly, the use of gas sensors is also increasing.

Currently, as a harmful gas detection sensor technology, a device method such as an electrical signal or a laser, a method of coating a color change composition on a substrate, a fiber type method using dyeing or electrospinning, etc. are used.

First, a separate device and power supply are required for device methods such as electrical signals and lasers, and when measuring harmful gases, the detection sensor equipment is installed in the place where the measurement is required, or a small equipment is carried by the operator to meet the needs. The sensing method is adopted. At this time, in the case of the stationary type, it is difficult to secure space and spread it at high cost, and in the case of the portable type, it is expensive and large in size, so there is a limitation in portability. There is this. In addition, a device employing such an electrical signal and a laser measurement method has poor flexibility, making it difficult to apply to wearables and applications requiring flexibility.

In the method of coating the color change composition on the substrate, the specific surface area of the non-woven material, paper, etc., which is the substrate used, the sensitivity of the sensor is low, and the durability and lifespan are low because it is composed of a simple physical bonding with the material, and washability There is a limit to its application in fields such as smart clothing and industrial work clothes.

In the fiber-type method using the dyeing, the materials applicable to the dyeing of the immersion dyeing or printing are limited, the sensitivity of the fibers is tens of micrometers, and the sensitivity is easy to fall, and the fabricated fibrous structure is thick, so flexibility can be reduced. In addition, in the case of the fiber-type method using the electrospinning method, the nano-size specific surface area is increased and the sensor response speed is fast, but the productivity is low, so the unit price is high, and the mechanical strength is low, so it is limited to application fields that require a certain strength such as protective clothing There is this.

An object to be solved by the present invention is to provide a fiber-type color change gas sensor and an article including the same, in which an operator can immediately recognize a dangerous situation by directly observing a color change with the eyes.

In order to solve this problem, according to one aspect of the present invention, there is provided a fiber-type color change gas sensor of the following embodiment.

According to a first implementation,

fibers having a composite cross-sectional structure or a heterogeneous cross-sectional structure; and a dye located on at least one of the surface and the inside of the fiber and exhibiting a color change when exposed to an acidic or basic gas; a fiber-type color change gas sensor comprising a.

According to a second embodiment, according to the first embodiment,

The fiber may be a long fiber having a strength of 1.5 g/d or more.

According to a third embodiment, according to the first or second embodiment,

The composite cross-sectional structure may be a sheath-core structure, a divided structure, a divided sheath-core structure, or a divided heteromorphic cross-sectional structure.

According to a fourth embodiment, according to a third embodiment,

When the composite cross-sectional structure is a cis-core structure, the dye is mixed only in the cis portion, or in the case of a divided structure, a dye showing a color change when exposed to the basic gas is provided on one side and a color when exposed to the acid gas on the other side Pigments showing changes may be mixed.

According to a fifth embodiment, according to any one of the first to fourth embodiments,

The pigments showing color change upon exposure to the acid gas are methylene blue, methyl yellow, thymol blue, pentamethoxy red, bromochresol green, Rhodamine, or a pigment containing two or more of them, and showing a color change upon exposure to the basic gas is phenophthalein, cresol red, alizarin yellow R (Alizarine Yellow R) or It may include two or more of these.

According to a sixth embodiment, according to any one of the first to fifth embodiments,

The fiber-type color change gas sensor may exhibit a color difference (ΔE) of two or more after exposure to acidic or basic gas compared to before exposure to acidic or basic gas.

According to a seventh embodiment,

Preparing a molten composition by adding a dye and a polymer for fiber formation that change color when exposed to acidic or basic gas to an extruder, mixing and melting;

melt spinning the molten composition into a fiber having a complex cross-sectional structure or a different cross-sectional structure through a complex cross-sectional nozzle or a different cross-sectional nozzle; and

winding and drawing the melt-spun fiber to make the fiber finer; containing,

A method for manufacturing a fiber-type color change gas sensor according to the first embodiment is provided.

According to the eighth embodiment, according to the seventh embodiment,

In the step of preparing the molten composition, when the dye and the polymer for fiber formation showing a color change when exposed to the acidic or basic gas are put into the extruder, the dye and the polymer for fiber formation are mixed in advance to prepare a master batch, , then the masterbatch and the polymer for forming pure fibers may be added and mixed.

According to the ninth embodiment, according to the eighth embodiment,

The content of the pigment showing a color change when exposed to the acidic or basic gas in the step of preparing the masterbatch may be 1 to 20% by weight based on the total weight of the masterbatch.

According to a tenth embodiment, according to any one of the seventh to ninth embodiments,

When the dye is maintained at 160 to 280° C. for 10 minutes or more, it may have a weight reduction characteristic of 50% or less.

According to an eleventh embodiment, according to any one of the seventh to tenth embodiments,

The composite cross-section nozzle may have a sheath-core structure, a divided structure, a divided sheath-core structure, or a divided heterogeneous cross-sectional structure, and the heterogeneous cross-section nozzle may have a polygonal cross-sectional structure or a hollow structure.

According to a twelfth embodiment, according to any one of the seventh to eleventh embodiments,

After the step of fibrillating, it may further include the step of twisting and braiding the fibrillated fibers.

According to one aspect of the present invention, an article of the following embodiments is provided.

According to a thirteenth embodiment, there is provided an article comprising the fibrous color change gas sensor of any one of the first to sixth embodiments.

According to the fourteenth embodiment, according to the thirteenth embodiment,

The article may be a garment, a glove, a hat, a belt, a mask, a sock, or a wristband.

According to a fifteenth embodiment, according to the thirteenth or fourteenth embodiment,

The fiber-type color change gas sensor may be applied to a part of the article in the form of knitting or embroidery.

The fiber-type color change gas sensor according to an embodiment of the present invention can be manufactured at a low cost compared to conventional expensive gas sensor equipment in a chemical industry. In addition, the fiber-type color change gas sensor is manufactured in a fiber state and can be provided as a product such as a protective suit itself through knitting or weaving, and can be easily embroidered on existing protective clothing, hats, etc. can be added As a result, the fiber-type color change gas sensor does not measure acid and base detection through a separate electric device, but directly observes the color change with the eyes, so that the operator can immediately recognize a dangerous situation, and the portability is great. Improved, it is possible to solve the cumbersome problem of determining the risk by checking whether or not the target gas is leaked and the concentration by separately mounting or carrying it in a required place based on the conventional stationary or portable device. In addition, the fiber-type color change gas sensor can be applied to a wearable device or a flexible electronic device that has recently been in the spotlight.

The following drawings attached to the present specification illustrate preferred embodiments of the present invention, and serve to further understand the technical spirit of the present invention together with the detailed description of the present invention to be described later. should not be construed as being limited only to
1 is a schematic diagram showing a cross-sectional structure of a fiber-type color change gas sensor according to an embodiment of the present invention.
2 is a photograph of a fiber-type color change gas sensor according to an embodiment of the present invention.
3 is an image of the cross-section of the gas-sensing color-changing fiber prepared in Examples 1 to 4 measured by FE-SEM.
4 is a graph showing reflectance over time for exposure to 50 ppm hydrochloric acid gas of the fiber-type color change gas sensor of Examples 1 and 2;
5 is a graph showing ΔE values according to time for exposure to 50 ppm hydrochloric acid gas of the fiber-type color change gas sensor of Examples 1 and 2;
6 is a photograph before and after exposure to acid (HCl) gas of the fiber-type color change gas sensor of Examples 1 and 2;
7 is a graph showing reflectance over time for exposure to 50 ppm ammonia gas of the fiber-type color change gas sensor of Examples 3 to 4;
8 is a graph showing ΔE values according to time for exposure to ammonia gas at 50 ppm of the fiber-type color change gas sensor of Examples 3 to 4;
9 is a photograph before and after exposure to base (ammonia) gas of the fiber-type color change gas sensor of Examples 3 to 4;
10 is a photograph showing a discoloration image of an embroidery sample using the fiber-type color change gas sensor of Example 1 after exposure to acid gas.

Hereinafter, the present invention will be described in detail. Prior to this, the terms or words used in the present specification and claims should not be construed as being limited to their ordinary or dictionary meanings, and the inventor should properly understand the concept of the term in order to best describe his invention. Based on the principle that it can be defined, it should be interpreted as meaning and concept consistent with the technical idea of the present invention.

Accordingly, the configuration shown in the embodiments described in this specification is only one of the most preferred embodiments of the present invention and does not represent all of the technical spirit of the present invention, so various equivalents that can be substituted for them at the time of the present application It should be understood that there may be variations and variations.

According to an aspect of the present invention, a fiber having a composite cross-sectional structure or a heterogeneous cross-sectional structure; and a dye located on at least one of the surface and the inside of the fiber and exhibiting a color change when exposed to an acidic or basic gas; a fiber-type color change gas sensor comprising a.

The fiber having a composite cross-sectional structure means a fiber having a cross-sectional structure formed by including two or more different fiber components. The fiber having such a composite cross-sectional structure may be implemented through composite spinning in which two or more different polymers are spun through one pore while independently controlling the discharge amount.

The composite cross-sectional structure includes a sheath-core structure in which one component is a core (core) and the other component surrounds it, a divided structure in which two components are attached to each other, a divided sheath-core structure, or a divided It may have a heteromorphic cross-sectional structure.

The sheath-core structure includes a mono sheath-core structure having one core portion, a multi-sheath-core structure having a plurality of core portions, and the like. In addition, the divided structure includes a side-by-side structure in which two components are attached to each other, or a multi-layered side-by-side structure in which two components are combined in a form in which they are alternately joined. In addition, the divided sheath-core structure refers to a structure in which the sheath portion surrounding the core portion is divided. The above divided heterogeneous cross-sectional structure refers to a polygonal heterogeneous cross-sectional structure with a smooth surface in a side-by-side structure.

The term "fiber having a heterogeneous cross-sectional structure" refers to a fiber in which the fiber has a non-circular cross-section, and examples of such a non-circular cross-sectional structure include a polygonal cross-sectional structure such as triangular, quadrilateral, pentagonal, or hexagonal; There may be a hollow structure and the like. Since the fiber having the heterogeneous cross-sectional structure has a larger specific surface area than the fiber having a circular cross-section, the contact area with the acid or base gas is widened, so that it is possible to check whether the gas is exposed more quickly and accurately.

1 is a schematic diagram showing a cross-sectional structure of a fiber-type color change gas sensor according to an embodiment of the present invention. Figure 1 (a) shows a mono cis-core structure, Figure 1 (b) shows a side-by-side structure, Figure 1 (c) shows a divided cis-core structure, (d) shows the heterogeneous cross-sectional structure of the 7-sided polygonal cross-section.

According to one embodiment of the present invention, in the case of the fiber having the sheath-core structure, a polymer resin mixed with a dye may be provided in the outer sheath portion, and a polymer resin may be disposed in the core portion to supplement mechanical strength.

In addition, in the case of the fiber having the split structure, one type is a polymer resin mixed with a dye (part a in Fig. 1 (b)), and the other side is a polymer resin for supplementing mechanical strength (Fig. 1 (b)). part b) of can be arranged. Alternatively, one type may be made of a base-sensing dye, and the other side may be made of an acid-sensing dye, so that the fiber can detect both acid/base.

In the case of the fiber having the divided sheath-core structure, a polymer resin for supplementing the mechanical strength of the core is disposed, a base sensing dye is provided on one side of the sheath (part c in FIG. Part d of (c) of 1) may be prepared with an acid-sensitive dye. In this case, while increasing the mechanical strength of the fiber, there is an advantage that the acid and the base can be simultaneously detected on the outside.

As the fiber, any material that can be melt-spun to have a composite cross-sectional structure or a heterogeneous cross-sectional structure may be applied without limitation.

Non-limiting examples of the fibers include polyamide (nylon 6, nylon 66, etc.), polylactic acid (PLA), polyolefin (polyethylene, polypropylene, etc.), polyacrylonitrile, polyacrylic acid, polyacrylate, polymethylmethacrylic acid Late, polyethyleneimide, cellulose acetate, cellulose triacetate, polyvinyl alcohol, polyvinylpyrrolidone, polyethylene glycol, sulfonated polysulfone, polyethylene oxide and polyvinyl acetate, polyester (polyethylene terephthalate, polybutylene tere phthalate, polytrimethylene terephthalate, polyethylene naphthalate, etc.), or two or more of these.

According to one embodiment of the present invention, the average diameter of the fibers may be 5 to 30 μm, or 5 to 18 μm, or 5 to 13 μm. When the average diameter of the fiber satisfies this range, it is advantageous because the specific surface area that can be sensed increases.

According to one embodiment of the present invention, the fiber may be a long fiber having a strength of 1.5 g/d or more, or 1.5 g/d to 7.0 g/d, or 2.5 g/d to 5.5 g/d.

As used herein, the long fiber refers to a fiber having an infinitely long fiber length as compared to a short fiber (or staple fiber) having a length of about 20 to 100 mm, and may also be called a filament fiber. have. The long fiber may be a monofilament yarn constituting a single yarn with only one strand, or a multifilament yarn in which several monofilament yarns are combined to form a single yarn.

Conventionally, in the case of fibers obtained by electrolytic solution spinning, the strength is very small (200 MPa or less), so it is difficult to apply to uses requiring a certain strength, such as protective clothing, and application in various forms in a nonwoven state may be disadvantageous.

As the pigment showing a color change upon exposure to the acidic or basic gas, a dye or pigment that is located on at least one of the surface and the inside of the fiber and causes a color change by an acidic or basic gas may be applied. As described above, since the fiber undergoes a melt spinning process to form a fiber having a composite cross-sectional structure or a heterogeneous cross-sectional structure, the dye must also have properties suitable for the melt spinning process. Therefore, the dye showing color change upon exposure to the acidic or basic gas needs thermal stability that can be used at 160 to 280° C., which is a temperature condition of a typical melt spinning process. For example, the dye exhibits a weight reduction characteristic of 50% or less when maintained for 10 minutes or more at the temperature condition of the melt spinning process, or more preferably, shows a weight reduction characteristic of 50% or less when maintained for 30 minutes or more may be desirable. In this case, the thermal stability of the dye may be evaluated using a method such as differential thermal analysis (DTA), differential scanning calorimetry (DSC), or thermogravimetry (TG).

The volume average particle diameter of the pigment may be 1 to 200 μm, or 1 to 100 μm, or 1 to 50 μm. In this case, when the volume average particle diameter of the dye satisfies this range, it is advantageous in that it is possible to minimize process problems such as clogging of the spinning nozzle.

As an example of the pigment, methylene blue (melting point 100-110 ℃), methyl yellow (melting point 111 ℃, methyl orange) (melting point) as a pigment showing a color change in acid gas leakage 300℃ or higher) Thymol Blue (melting point 221~224℃), Pentamethoxy Red (melting point 146-148℃), Bromocresol green (melting point 225℃), Rhodamine (Rhodamine) (melting point 210~211℃), etc., and it is a pigment that shows color change when basic gas leaks. Phenophthalein (melting point 258~263℃), Cresol Red (melting point 250℃) , Alizarin Yellow R (Alizarine Yellow R) (melting point 253 ~ 254 ℃), and the like may be used, but is not limited thereto.

According to one embodiment of the present invention, the fiber-type color change gas sensor contains a dye capable of detecting acid and base gas or both acid/base on the surface, so that when exposed to gas within 40 seconds, or within 30 seconds , or may be discolored within 10 seconds.

As used herein, the color change means showing a color difference (ΔE) of 2 or more, or 5 or more after exposure to acidic or basic gas compared to the first fiber-type color change gas sensor before contact with acidic or basic gas. can

At this time, ΔE is a value calculated with the distance of L*, a*, b* values obtained from the CIE L*a*b* colorimetric system measured from the spectrophotometer, and is based on the sample in the initial state (before gas exposure). ΔE is calculated from the following formula.

The fiber-type color change gas sensor according to an embodiment of the present invention does not measure acid and base detection through a separate electric device, but directly observes the color change with the eyes, so that the operator can immediately recognize a dangerous situation.

The fiber-type color change gas sensor is manufactured in the form of melt spinning together with a fiber-forming polymer and a dye, and the dye is firmly bound to the surface and inside of the fiber. Therefore, compared to the technology of applying a dye that changes color to acidic or basic gas by a conventional dyeing method or coating method, the washing durability of the article to which this fiber-type color change gas sensor is applied is remarkably superior, even after repeated washing. It can be reused without deterioration of color change characteristics.

According to one embodiment of the present invention, the content of the dye in the fiber type color change gas sensor may be 1 to 5 wt%, or 2 to 3 wt% based on the total weight of the fiber type color change gas sensor. When the content of the dye satisfies this range, it may be advantageous in terms of sensitivity of the sensor.

In addition, when the fiber-type color change gas sensor has a sheath-core structure, the cross-sectional area ratio of the sheath portion and the core portion may be 2:8 to 5:5, or 3:7 to 4:6. When the cross-sectional area ratio of the sheath portion and the core portion satisfies this range, it may be advantageous in terms of mechanical strength and radiation of the color change gas sensor.

In addition, when the fiber-type color change gas sensor has a sheath-core structure and a pigment is included only in the sheath, the content of the pigment is 1 to 5% by weight, or 2 to 3% by weight based on the total weight of the sheath. can be When the content of the dye satisfies this range, it may be advantageous in terms of gas sensing performance of the sensor.

In addition, when the fiber-type color change gas sensor has a side-by-side structure among the divided structures, the cross-sectional area ratio of one side and the other side may be 5:5 to 7:3, or 6:4 to 4:6. have.

When the cross-sectional area ratio of the one side and the other side satisfies this range, it may be advantageous in terms of sensing performance and radiation fairness of the sensor.

In addition, when the fiber-type color change gas sensor has a side-by-side structure and a dye is included in only one side part, the content of the dye is 1 to 5% by weight based on the total weight of the one side part, or 2 to 3% by weight. In addition, when the fiber-type color change gas sensor has a side-by-side structure and includes an acid gas sensing dye in one side portion and a basic gas detection dye in the other side portion, the content of each dye is respectively Independently, it may be 1 to 5 wt%, or 2 to 3 wt%, based on the total weight of one side part. When the content of the dye satisfies this range, it may be advantageous in terms of gas sensing performance and radiation fairness.

According to one aspect of the present invention, there is provided a method for manufacturing the above-described fiber-type color change gas sensor comprising the following steps.

Preparing a molten composition by adding a dye and a polymer for fiber formation that change color when exposed to acidic or basic gas to an extruder (extruder), mixing and melting;

melt spinning the molten composition into a fiber having a complex cross-sectional structure or a different cross-sectional structure through a complex cross-sectional nozzle or a different cross-sectional nozzle;

It may include; winding and stretching the melt-spun fiber to make the fiber finer.

At this time, when the dye and the polymer for fiber formation, which show color change when exposed to the acidic or basic gas, are put into the extruder (extruder), a master batch is prepared by mixing the dye and the polymer for fiber formation in advance, and then Masterbatch and pure fiber-forming polymer may be added and mixed.

According to one embodiment of the present invention, the content of the pigment showing a color change when exposed to the acidic or basic gas may be 1 to 20% by weight, or 1 to 10% by weight based on the total weight of the masterbatch. In the case of using the masterbatch as described above, it is advantageous to control the content of the dye contained in the final fiber, and it is possible to enable more uniform mixing between the dye and the polymer for fiber formation in the extruder.

The composite cross-sectional nozzle has a sheath-core structure, a divided structure, a divided sheath-core structure, or a divided heterogeneous cross-sectional structure to correspond to the cross-sectional structure of the above-described fiber, and the heterogeneous cross-section nozzle is triangular, quadrangular, Polygonal cross-sectional structure such as pentagonal, hexagonal, etc. It may have a polygonal cross-sectional structure or a hollow structure.

According to one embodiment of the present invention, the winding speed in the step of thinning is 800 to 5,000 m/min, and the draw ratio can be adjusted to 2 to 4 times.

In addition, the fibrillated fiber may be further subjected to a process of selectively twisting and braiding.

According to one aspect of the present invention, there is provided an article including the above-described fiber-type color change gas sensor.

The article may be a garment, a glove, a hat, a belt, a mask, a sock, or a wristband, and the like. In this case, the fiber-type color change gas sensor may be knitted or woven to obtain a fiber structure such as knitted or woven fabric, and may be directly manufactured into articles such as clothes, masks, hats, gloves, socks, belts, and wrist bands. In addition, the fiber-type color change gas sensor may be applied to an existing article such as clothes in the form of knitting or embroidery, limited to a partial area.

As such, since the fiber-type color change gas sensor according to an embodiment of the present invention can be directly manufactured as a fiber structure or applied in the form of knitting or embroidery only to a part of an existing article, in the prior art, for detecting harmful gases Even if the operator does not have a separate device (stationary or portable), it can be conveniently worn to detect exposure to harmful gases immediately.

Hereinafter, to help the understanding of the present invention, examples will be described in detail. However, the embodiments according to the present invention may be modified in various other forms, and the scope of the present invention should not be construed as being limited to the following examples. The embodiments of the present invention are provided to more completely explain the present invention to those of ordinary skill in the art.

Example 1

A fiber-type color change gas sensor capable of detecting acid was prepared as follows through the melt spinning method.

After melting nylon 6 (Grade1011BRT, Hyosung, Korea) resin through an extruder (twin extruder) temperature controlled at 260°C, Rhodamine B, a pigment that changes color when exposed to acid gas ( CAS# 81-88-9, Sigma-Aldrich, USA) 10 wt% was injected into the hopper and uniformly dispersed in the polymer resin. The molten resin was discharged through a nozzle, passed through a coagulation bath at 25° C., and the solidified resin was cut into 3 mm to prepare a masterbatch containing a color change when exposed to acid gas.

During melt spinning, a sheath/core nozzle was used, the diameter of the nozzle used was 0.4Φ, the number of holes was 36 holes, the ratio of polymer discharge between the sheath and core nozzle was 4:6, and the nozzle temperature was 280. ℃ was. In the sheath part, the prepared nylon 6/rhodamine 10 wt% (wt%) masterbatch and pure nylon 6 raw material are mixed, and the content of the pigment showing color change when exposed to acidic gas is 1 wt% based on the total weight of the sheath part. Nylon 6 / rhodamine resin that can detect acid was added as much as possible, and polypropylene (PP) (HP552R, Polymirae, Korea) resin that can support fiber properties was added to the core part to provide a sheath of nylon 6 (rhodamine) / PP. A fiber-type color change gas sensor capable of sensing an acid having a /core structure was manufactured.

Example 2

In the sheath part, nylon 6/rhodamine 10 wt% masterbatch and pure nylon 6 raw material are mixed and acid-sensing nylon 6/rhodamine resin with 3 wt% of pigment that changes color when exposed to acid gas is added. An acid-sensing fiber-type color change gas sensor having a sheath/core structure of nylon 6 (rhodamine)/PP was prepared in the same manner as in Example 1, except that

Example 3

A fiber-type color change gas sensor capable of detecting a base was prepared as follows through the melt spinning method.

Polylactic acid (PLA) (6201D, IngeoTM, USA) resin is melted through an extruder (twin extruder) temperature controlled at 160°C, and Alizarine Yellow R (CAS# 2243), a pigment that changes color when exposed to basic gas -76-7, Sigma-Aldrich, USA) 10 wt% was injected into the hopper and uniformly dispersed in the polymer resin. The molten resin was discharged through a nozzle, passed through a coagulation bath at 25°C, and the solidified resin was cut into 3 mm to prepare a masterbatch containing a color change when exposed to basic gas.

During melt spinning, a sheath/core nozzle was used, the diameter of the nozzle used was 0.3Φ, the number of holes was 36 holes, the S/C ratio was 4:6, and the nozzle temperature was 200°C. In the sheath part, PLA/Alizarine Yellow R resin capable of detecting a base with 1 wt% of a pigment that shows color change when exposed to basic gas by mixing the manufactured PLA/Alizarine Yellow R 10wt% masterbatch and pure PLA raw material was added. In the core part, polypropylene (PP) (HP552R, Polymirae, Korea) resin that can support fiber properties is put in, and a base-detectable fiber-type color change gas having a sheath/core structure of PLA (Alizarine Yellow R)/PP The sensor was fabricated.

Example 4

PLA/Alizarine Yellow R resin capable of detecting a base with 3 wt% of a pigment that changes color when exposed to basic gas by mixing PLA/Alizarine Yellow R 10 wt% masterbatch and pure PLA raw material in the sheath A fiber-type color change gas sensor capable of detecting a base having a sheath/core structure of PLA (Alizarine Yellow R)/PP was prepared in the same manner as in Example 1, except that.

2 shows photographs of the fiber-type color change gas sensor prepared in Examples 1 to 4.

Comparative Example 1

In Example 3, melt spinning was performed with a single nozzle instead of a sheath/core nozzle at the same content as the PLA/Alizarine Yellow R resin injected into the sheath. The diameter of the nozzle used at this time was 0.3Φ, the odd number was 10 holes, and the nozzle temperature was 200°C. In the case of single spinning, spinning was impossible due to high pack pressure due to aggregation of the dispersed raw materials.

Experimental Example 1; Cross-section confirmation of fibers manufactured with sheath/core composite nozzles

3 is an image of the cross-section of the gas-sensing color-changing fiber prepared in Examples 1 to 4 measured by FE-SEM. It was confirmed that the sheath/core structure of the melt-spun fiber was well formed, and it was confirmed that the diameter of the entire fiber tends to increase as the content of the pigment that changes color when exposed to acidic basic gas injected into the sheath increases. did. In addition, it was confirmed that the fiber containing the pigment showing color change when exposed to acidic or basic gas was located in the sheath portion of the surface, and the PP for supplementing strength and radioactivity was located in the core portion.

Experimental Example 2; fiber strength

In order to check the fiber denier, strength and elongation of Examples 1 to 4, a short fiber physical property measuring instrument (Favimat, tetechno, Germany) was used, the gauge length was 20 mm, and the crosshead speed was 10 mm/min. About 10 specimens were measured for each sample, and the result was calculated as the average value. Table 1 shows the fineness, strength, and elongation of Examples 1 to 4.

In Examples 1 and 2, it can be confirmed that the fineness of the fiber increases and the strength decreases relatively as the content of the pigment showing a color change when exposed to the acid gas injected into the sheath under the same spinning conditions increases. there was. In the case of Examples 3 and 4, as the content of the pigment showing a color change upon exposure to the basic gas injected into the sheath increased, the fineness was slightly decreased, and it was confirmed that the strength was similar.

fineness (den) Strength (g/den) Elongation (%) Example 1 2.8 4.7 22 Example 2 3.74 3.41 37.2 Example 3 3.1 5.4 30.1 Example 4 2.7 5.4 32.1

Experimental Example 3; acid gas test

In order to confirm the color change performance of the fiber-type color change gas sensor of Examples 1 and 2 under acid gas, the sample was exposed to an acid (HCl) gas at a concentration of 50 ppm and the color change with time was observed. The gas test equipment is a home-made equipment that is connected to a colorimeter (Color-eye 7000A spectrophotometer, X-rite, USA) and is designed to measure and monitor real-time color change. As a brief description of the device configuration of this equipment, it is possible to monitor the color change of the color change fiber in real time by measuring the reflectance after connecting the stainless chamber with the specimen fixed to the colorimeter and flowing the set gas concentration through the gas circulation device. Colorimetry was performed for a total of 5 minutes at 10-second intervals using a macro program as a system.

4 is a graph showing reflectance over time for exposure to 50 ppm hydrochloric acid gas of the fiber-type color change gas sensor of Examples 1 and 2;

Referring to FIG. 4 , it was confirmed that the fiber-type color change gas sensor of Examples 1 and 2 continuously changed the reflectance with time under hydrochloric acid gas.

5 is a graph showing ΔE values according to time for exposure to 50 ppm hydrochloric acid gas of the fiber-type color change gas sensor of Examples 1 and 2; Table 2 shows the response speed of the fiber-type color change gas sensor of Examples 1 and 2, and in this experiment, the response speed was based on the time of the starting point at which the ΔE value was changed by 5 or more. In the case of Examples 1 and 2, the response speed was 40 seconds, and the ΔE value at that time was shown in the table.

Response speed (s) △E Example 1 40 5.3 Example 2 40 8.2

Referring to FIG. 5 and Table 2, as a result of judging the response speed based on the time when the ΔE value becomes 5 or more, it was confirmed that Examples 1 and 2 showed a clear color change within 40 seconds. At this time, ΔE is a value calculated with the distances of L*, a*, and b* values obtained from the CIE L*a*b* colorimetric system measured from the spectrophotometer. it is calculated

6 is a photograph before and after exposure to acid (HCl) gas of the fiber-type color change gas sensor of Examples 1 and 2;

Referring to FIG. 6 , it was confirmed that the fiber-type color change gas sensor of Examples 1 and 2 changed color from white or beige to purple when exposed to gas.

Experimental Example 4; base gas test

In order to confirm the color change performance of the fiber-type color change gas sensor of Examples 3 to 4 under a base gas _{, the sample was exposed to a base (NH 3} ) gas at a concentration of 50 ppm and the color change over time was observed. As the gas test equipment, the same equipment as in Experimental Example 3 was used.

7 is a graph showing reflectance over time for exposure to 50 ppm ammonia gas of the fiber-type color change gas sensor of Examples 3 to 4;

Referring to FIG. 7 , it was confirmed that the fiber-type color change gas sensor of Examples 3 to 4 had a rapid change in reflectance with time under ammonia gas.

8 is a graph showing ΔE values according to time for exposure to ammonia gas at 50 ppm of the fiber-type color change gas sensor of Examples 3 to 4; Table 3 shows the response speed of the fiber-type color change gas sensor of Examples 3 to 4, and in this experiment, the response speed was based on the time of the starting point at which the ΔE value was changed by 5 or more. In the case of Examples 3 and 4, the response speed was 10 seconds, and ΔE values at that time were shown in the table.

Referring to FIG. 8 and Table 3, as a result of determining the response speed based on the time when the ΔE value becomes 5 or more, it was confirmed that Examples 3 and 4 showed a clear color change within 10 seconds.

Response speed (s) △E Example 3 10 36.6 Example 4 10 39.6

9 is a photograph before and after exposure to base (ammonia) gas of the fiber-type color change gas sensor of Examples 3 to 4;

Referring to FIG. 9 , it was confirmed that the fiber-type color change gas sensor of Examples 3 to 4 changed color from yellow to turbid yellow or brown when exposed to gas.

Experimental Example 5; Acid gas testing of embroidery samples

An embroidery sample was prepared by a basic straight stitch method according to the pattern of the fiber-type color change gas sensor of Example 1 on a general polyester fabric (ISO 105-F04 polyester standard white fabric).

After exposing the prepared embroidery sample using a gas test equipment to 200 ppm of acid (HCl) gas for 5 minutes, the color change was observed, and the results are shown in FIG. 10 . Referring to FIG. 10 , in the embroidery sample using the fiber-type color change gas sensor of Example 1, a vivid color change was observed after exposure to acid gas, and the work article (clothes, gloves, shoes, belt, mask, hat, etc.) ), it is expected that the operator can quickly check the presence of harmful gases with the naked eye.

Claims (15)

fibers having a composite cross-sectional structure or a heterogeneous cross-sectional structure; and a dye located on at least one of the surface and the inside of the fiber and exhibiting color change when exposed to acidic or basic gas. According to claim 1,
Fiber-type color change gas sensor, characterized in that the fiber is a long fiber having a strength of 1.5 g/d or more. According to claim 1,
The fiber type color change gas sensor, characterized in that the composite cross-sectional structure is a sheath-core structure, a divided structure, a divided sheath-core structure, or a divided heterogeneous cross-sectional structure. 4. The method of claim 3,
When the composite cross-sectional structure is a cis-core structure, the dye is mixed only in the cis portion, or in the case of a divided structure, a dye showing a color change when exposed to the basic gas is provided on one side and a color when exposed to the acid gas on the other side A fiber-type color change gas sensor, characterized in that a dye showing a change is mixed. According to claim 1,
The pigments showing color change upon exposure to the acid gas are methylene blue, methyl yellow, thymol blue, pentamethoxy red, bromochresol green, Rhodamine, or a pigment containing two or more of them, and showing a color change upon exposure to the basic gas is phenophthalein, cresol red, alizarin yellow R, or Fiber-type color change gas sensor comprising two or more of them. According to claim 1,
Fiber type color change gas sensor, characterized in that the fiber type color change gas sensor exhibits a color difference (ΔE) of two or more after exposure to acidic or basic gas compared to before exposure to acidic or basic gas. Preparing a molten composition by adding a dye and a polymer for fiber formation that change color when exposed to acidic or basic gas to an extruder, mixing and melting;
melt spinning the molten composition into a fiber having a complex cross-sectional structure or a different cross-sectional structure through a complex cross-sectional nozzle or a different cross-sectional nozzle; and
winding and drawing the melt-spun fiber to make the fiber finer; containing,
The method for manufacturing a fiber-type color change gas sensor according to claim 1 . 8. The method of claim 7,
In the step of preparing the molten composition, when the dye and the polymer for fiber formation showing a color change when exposed to the acidic or basic gas are put into the extruder, the dye and the polymer for forming the fiber are mixed in advance to prepare a master batch, , Then, a method of manufacturing a fiber-type color change gas sensor, characterized in that the mixing of the master batch and the polymer for forming pure fibers. 9. The method of claim 8,
Method for producing a fiber-type color change gas sensor, characterized in that the content of the pigment showing color change when exposed to the acidic or basic gas in the step of preparing the masterbatch is 1 to 20% by weight based on the total weight of the masterbatch . 8. The method of claim 7,
A method of manufacturing a fiber-type color change gas sensor, characterized in that the dye has a weight reduction characteristic of 50% or less when maintained at 160 to 280° C. for 10 minutes or more. 8. The method of claim 7,
Fiber-type color change, characterized in that the composite cross-section nozzle has a sheath-core structure, a divided structure, a divided sheath-core structure, or a divided irregular cross-sectional structure, and the irregular cross-section nozzle has a polygonal cross-sectional structure or a hollow structure A method of manufacturing a gas sensor. 8. The method of claim 7,
After the step of fibrillating, the method of manufacturing a fiber-type color change gas sensor, characterized in that it further comprises the step of twisting and braiding the fibrillated fiber. An article comprising the fiber-type color change gas sensor of any one of claims 1 to 6. 14. The method of claim 13,
wherein the article is a garment, a glove, a hat, a belt, a mask, a sock, or a wristband. 14. The method of claim 13,
The article, characterized in that the fiber-type color change gas sensor is applied to a part of the article in the form of knitting or embroidery.

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