KR102685161B1 - Color-changing photonic crystal structure containing a titanium-composite and an aldehyde sensor manufactured using the same - Google Patents

Abstract

The present disclosure includes a high refractive index layer and a low refractive index response layer having a high refractive index difference, has excellent reflectance for light of a specific wavelength, and not only is it easy to control the refractive index of the high refractive index layer, but the low refractive index response layer is resistant to humidity and aldehyde. By having excellent sensitivity to aldehyde-based materials, we provide a color conversion one-dimensional photonic crystal structure that has significantly excellent color conversion visibility when exposed to trace amounts of aldehyde-based materials, and includes this, allowing users to easily see traces of aldehyde-based materials with the naked eye. It can be useful as an aldehyde detection sensor that can be observed.

Description

Humidity-sensitive one-dimensional photonic crystal structure and color conversion sensor for aldehyde detection using the same {Color-changing photonic crystal structure containing a titanium-composite and an aldehyde sensor manufactured using the same}

The present invention provides a one-dimensional photonic crystal structure in which high refractive index layers and low refractive index response layers having a high refractive index difference are alternately stacked, and a color conversion sensor for detecting aldehyde using the same.

Aldehyde-based substances, especially formaldehyde and acetaldehyde, mainly cause sick building syndrome and are classified as carcinogens by the World Health Organization, and are known to be very harmful to the human body even at concentrations of several ppm.

Problems caused by formaldehyde and acetaldehyde are more serious in closed environments with poor ventilation, but since ventilation is generally poor for many reasons such as heating and cooling and fine dust, the damage caused by this is gradually increasing.

To solve this problem, existing high-accuracy equipment such as gas chromatography-mass spectrometry (GC-MS) or high-performance liquid chromatography (HPLC), which can detect trace amounts of formaldehyde and acetaldehyde, has been used. , they are expensive and require separate space for equipment installation, it is difficult to detect formaldehyde or acetaldehyde in real time, and the user must be highly trained to operate the device.

In order to solve the problems of the conventional sensors, sensors capable of visual detection have been developed based on various materials such as organic salts/pigments, metal-organic-skeletons, cellulose, and metal oxide semiconductors. However, to date, sensors capable of visual detection have been developed. The reported visual detection sensors have many limitations for commercial use due to problems of low visibility and low productivity.

In order to solve the problems of conventional visual detection sensors, the inventors of the present invention attempted to provide a sensor that allows users to easily visually detect formaldehyde and acetaldehyde based on a color-converting 1D photonic crystal structure. .

A photonic crystal structure is a structure in which dielectric materials with different refractive indices are periodically stacked. Among the light incident on this repetitive structure, light in a specific wavelength range is selectively reflected through overlapping interference, that is, , refers to a structure that forms a light-forbidden zone.

In general, color conversion photonic crystal structures are classified into one-dimensional, two-dimensional, and three-dimensional photonic crystal structures depending on the structural arrangement and periodicity. Among the photonic crystal structures, the one-dimensional photonic crystal structure can be manufactured simply by simply stacking two materials with different refractive indices, and has the advantage of being easy to control optical properties by adjusting the refractive index and thickness of the two layers. Due to these advantages, the one-dimensional photonic crystal structure is widely used not only as photonic crystal fibers, light-emitting devices, and photovoltaic devices, but also as photonic crystal sensors that detect various stimuli. The photonic crystal sensor shows changes in reflection color depending on temperature, pressure, or sensitive material, helping users perceive changes in the external environment with the naked eye.

In order to commercialize a photonic crystal sensor, it must be easy to manufacture in a film form that is easy to handle, visual visibility must be high, and the price of the materials used must not be high. The above-described one-dimensional photonic crystal structure satisfies the above conditions and has high commercialization potential, but to date, a sensor based on the one-dimensional photonic crystal structure capable of selectively detecting only formaldehyde and acetaldehyde has not been reported.

Accordingly, there is an urgent need to develop a color-converting one-dimensional photonic crystal structure that can selectively and sensitively detect only formaldehyde or acetaldehyde with the naked eye, has excellent reproducibility, high visibility, and is reusable.

Republic of Korea Patent Publication No. 10-2017-0068274 A (2017.06.19)

One embodiment of the present invention is to provide a color conversion one-dimensional photonic crystal structure that has immediate color conversion and excellent visibility in various relative humidity environments.

One embodiment of the present invention is to provide an aldehyde detection sensor capable of detecting with the naked eye even a trace amount of an aldehyde-based material using the color-converting one-dimensional photonic crystal structure.

One embodiment of the present invention is to provide a color conversion one-dimensional photonic crystal structure that can be reused through a simple process and can maintain excellent initial color conversion visibility and excellent sensitivity even when reused.

One embodiment of the present invention seeks to provide a color conversion one-dimensional photonic crystal structure that can not only detect aldehyde-based substances but also remove them, and an aldehyde detection sensor including the same.

As an embodiment of the present invention, the color conversion one-dimensional photonic crystal structure is a high refractive index layer formed including a titanium-composite containing repeating units represented by the following formulas 1 to 3, and repeating represented by the formulas 3 and 4 below It may include a low refractive index sensitive layer formed including a sensitive copolymer containing a unit, and the high refractive index layer and the low refractive index sensitive layer may be alternately laminated.

[Formula 1]

[Formula 2]

[Formula 3]

[Formula 4]

(In Formulas 1 to 4, R ₁ , R ₂ , R ₄ and R ₇ are independently hydrogen or straight-chain or branched C ₁ -C ₇ alkyl, is a titanium oxide network structure, A ₁ , A ₂ and A ₄ are independently a single bond or a straight-chain or branched C ₁ -C ₇ alkylene, and R ₃ is hydrogen or a straight-chain or branched C ₁ -C ₇ alkyl, A ₃ is *-O-* or *-NH-*, R ₅ and R ₆ are independently straight-chain or branched C ₁ -C ₇ alkyl, and n and m are independently of each other It is an integer from 0 to 4.)

As an embodiment of the present invention, in Formulas 1 to 4, R ₁ , R ₂ , R ₄ and R ₇ are independently hydrogen, methyl or ethyl, Is ( ) It is a titanium oxide network structure containing _n , A ₁ and A ₂ are independently a single bond, methylene or ethylene, R ₃ is a straight or branched chain C ₁ -C ₄ alkyl, and A ₃ is *-O- *, A ₄ is straight chain C ₁ -C ₄ alkylene, R ₅ and R ₆ are independently straight chain or branched chain C ₁ -C ₄ alkyl, and n and m are independently integers from 0 to 2. there is.

As an embodiment of the present invention, the titanium-complex may contain 1 to 50 mol% of the repeating unit represented by Formula 1, based on the total repeating units.

As an embodiment of the present invention, the sensitive copolymer may contain 50 to 99 mol% of the repeating unit represented by Formula 4.

As an embodiment of the present invention, the titanium-composite may be represented by the following formula (5), and the sensitive copolymer may be represented by the following formula (6).

[Formula 5]

[Formula 6]

(In Formula 5, a, b and c are rational numbers satisfying a+b+c=1, 0.08≤a≤0.15, 0.02≤b≤0.05 and 0.8≤c≤0.9, is a titanium oxide network structure, and in Formula 6, d and e are rational numbers satisfying d+e=1, 0.9≤d≤0.99, and 0.01≤e≤0.1.)

As an embodiment of the present invention, the titanium-composite may include 50 to 80% by weight of a titanium oxide network structure based on the total mass.

As an embodiment of the present invention, the color-converting one-dimensional photonic crystal structure may be a stack of 20 or less layers of high-refractive-index layers and low-refractive-responsive layers.

As an embodiment of the present invention, the high refractive index layer may have a refractive index of 1.5 to 3.0 for visible light with a wavelength of 633 nm, and a refractive index difference from the sensitive layer may be 0.07 or more.

As an embodiment of the present invention, the thickness of the high refractive index layer may be 20 to 70 nm.

As an embodiment of the present invention, the thickness of the low refractive index response layer may be 1 to 200 nm.

As an embodiment of the present invention, the color conversion one-dimensional photonic crystal structure may have a maximum reflectance of 10% or more as measured by a spectrometer.

As an embodiment of the present invention, the color conversion one-dimensional photonic crystal structure increases the wavelength range of light with maximum reflectance as relative humidity increases, and when exposed to an aldehyde-based material, light with maximum reflectance as relative humidity increases. It may be characterized by a decrease in the growth rate of the wavelength range.

As an embodiment of the present invention, the color conversion one-dimensional photonic crystal structure may exhibit a color change at a relative humidity of 30% or more.

As an embodiment of the present invention, the color conversion one-dimensional photonic crystal structure may be characterized in that it includes a reduction reaction and can be reused.

One embodiment of the present invention can provide an aldehyde detection sensor including the color conversion one-dimensional photonic crystal structure.

As an embodiment of the present invention, the aldehyde detection sensor may detect a sensing object containing more than 1 ppm of formaldehyde, more than 50 ppm of acetaldehyde, or a mixture thereof.

One embodiment of the present invention includes preparing a first composition comprising a titanium-complex containing repeating units represented by the following formulas 7 to 9, and a sensitive composition containing the repeating units represented by the following formulas 9 and 10. To provide a method for producing a color conversion one-dimensional photonic crystal structure comprising the steps of preparing a second composition containing a copolymer and forming a high refractive index layer and a low refractive index response layer by crossing the first composition and the second composition. You can.

[Formula 7]

[Formula 8]

[Formula 9]

[Formula 10]

(In Formulas 7 to 10, R ₈ , R ₉ , R ₁₁ and R ₁₄ are independently hydrogen or straight-chain or branched C ₁ -C ₇ alkyl, is a titanium oxide network structure, A ₅ , A ₆ and A ₈ are independently a single bond or a straight-chain or branched C ₁ -C ₇ alkylene, and R ₁₀ is hydrogen or a straight-chain or branched C ₁ -C ₇ alkyl, A ₇ is *-O-* or *-NH-*, R ₁₂ and R ₁₃ are independently straight-chain or branched C ₁ -C ₇ alkyl, and n and m are independently of each other It is an integer from 0 to 4.

As an embodiment of the present invention, the high refractive index layer may be formed by coating, drying, and photocuring the first composition.

As an embodiment of the present invention, the color conversion one-dimensional photonic crystal structure has a refractive index difference between the high refractive index layer and the low refractive index response layer of at least 0.07, so that the reflectance measured with a spectrometer (Ocean Optics USB4000-UV-VIS-ES) It can have significantly excellent color conversion visibility of 10% or more, preferably 30% or more, more preferably 60% or more, or 70% or more.

As an example of the present invention, the color-converting one-dimensional photonic crystal structure can display various reflection colors that can be observed with the naked eye even in an environment with a relative humidity of 30% or more or 40% or more.

As an embodiment of the present invention, the color conversion one-dimensional photonic crystal structure can exhibit a rapid color change that can be observed with the naked eye even when exposed to a trace amount of formaldehyde or acetaldehyde for just 20 minutes.

As an embodiment of the present invention, the one-dimensional photonic crystal structure can remove aldehydes in the air, thereby fundamentally preventing problems such as respiratory problems, skin diseases, and hormonal disturbances caused by aldehyde-based substances.

As an embodiment of the present invention, the one-dimensional photonic crystal structure can maintain its initial optical and chemical properties even when reused through a simple process, and thus has excellent environmental friendliness and excellent economic efficiency.

Therefore, since the humidity-sensitive one-dimensional photonic crystal structure has excellent reactivity, especially high reactivity with formaldehyde and acetaldehyde, it can be more usefully used as a formaldehyde and acetaldehyde detection sensor with significantly high visibility.

Figure 1 shows the color change according to relative humidity when the color conversion one-dimensional photonic crystal structure of Example 1 was not exposed to formaldehyde and when exposed to formaldehyde at concentrations of 1 ppm and 50 ppm for 20 minutes, respectively. .
Figure 2 shows the wavelength of 200 to 900 nm according to the change in relative humidity when the color conversion one-dimensional photonic crystal structure of Example 1 was not exposed to formaldehyde and when exposed to formaldehyde at concentrations of 1 ppm and 50 ppm, respectively, for 20 minutes. This is the result of measuring the change in reflectance in the range.
Figure 3 shows the color change according to relative humidity when the one-dimensional photonic crystal structure of Example 1 was not exposed to acetaldehyde and when exposed to acetaldehyde at concentrations of 50 ppm and 100 ppm for 20 minutes, respectively.
Figure 4 shows the wavelength of 200 to 900 nm according to the change in relative humidity when the color conversion one-dimensional photonic crystal structure of Example 1 was not exposed to acetaldehyde and when exposed to acetaldehyde at concentrations of 50 ppm and 100 ppm, respectively, for 20 minutes. This is the result of measuring the change in reflectance in the range.
Figure 5 shows a sensor in which the one-dimensional photonic crystal structure of Example 1 loses its humidity-responsive color conversion characteristics due to exposure to formaldehyde or acetaldehyde, and then changes color again according to the change in relative humidity when immersed in a 1 molar aqueous solution of hydrochloric acid. This shows that it can be recycled.
Figure 6 shows the color conversion one-dimensional photonic crystal structure of Example 1 in formaldehyde, acetaldehyde, propionaldehyde, butyraldehyde, acetone, dichloromethane, chloroform, ethyl acetate, diethyl ether, benzene, toluene, xylene, and methanol. After each was immersed for 20 minutes and dried, the reflectance was measured in the wavelength range of 200 to 800 nm in an environment with a relative humidity of 70%.

Hereinafter, a one-dimensional photonic crystal structure according to the present invention and an aldehyde detection sensor including the same will be described through examples. However, the following examples are only for reference to explain the present invention in detail, and the present invention is not limited thereto, and may be implemented in various forms.

Additionally, unless otherwise defined, all technical and scientific terms have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention pertains. The terminology used in the description herein is merely to effectively describe particular embodiments and is not intended to limit the invention.

In addition, in the following description, descriptions of known effects and configurations that may unnecessarily obscure the gist of the present invention are omitted. In the following specification, units used without special mention are based on weight, and as an example, units of % or ratio mean weight % or weight ratio.

Additionally, as used herein in the specification, the singular forms “a,” “an,” and “the” are intended to include the plural forms as well, unless the context clearly dictates otherwise.

In this specification, “single bond” means direct connection.

In this specification, ″C ₁ -C _n ″ refers to a hydrocarbon containing 1 to n carbon atoms.

In this specification, “single bond” may mean direct connection.

Conventional aldehyde detection sensors have the problem of low compatibility because they have high prices, very large equipment volumes, and require high expertise from users. To solve this problem, the present inventors have developed a new one-dimensional photonic crystal structure that has excellent processability, low volume and excellent reactivity of aldehyde-based materials with humidity, and detects trace amounts of aldehyde-based materials at least at a relative humidity of 30%, thereby producing excellent We attempted to provide an aldehyde detection sensor that can be recognized by users through color conversion visibility.

Hereinafter, the color conversion one-dimensional photonic crystal structure of the present invention will be described.

As an embodiment of the present invention, the color conversion one-dimensional photonic crystal structure is a high refractive index layer formed including a titanium-composite containing repeating units represented by the following formulas 1 to 3, and repeating represented by the formulas 3 and 4 below It may include a low refractive index sensitive layer formed including a sensitive copolymer containing a unit, and the high refractive index layer and the low refractive index sensitive layer may be alternately laminated.

[Formula 1]

[Formula 2]

[Formula 3]

[Formula 4]

(In Formulas 1 to 4, R ₁ , R ₂ , R ₄ and R ₇ are independently hydrogen or straight-chain or branched C ₁ -C ₇ alkyl, is a titanium oxide network structure, A ₁ , A ₂ and A ₄ are independently a single bond or a straight-chain or branched C ₁ -C ₇ alkylene, and R ₃ is hydrogen or a straight-chain or branched C ₁ -C ₇ alkyl, A ₃ is *-O-* or *-NH-*, R ₅ and R ₆ are independently straight-chain or branched C ₁ -C ₇ alkyl, and n and m are independently of each other It is an integer from 0 to 4.)

The titanium-composite is an organic-inorganic hydride material containing a titanium oxide network structure, which solves the limitation of refractive index of conventional polymer resins and can have excellent color conversion visibility even with a small number of layers.

More specifically, the titanium-composite contains a repeating unit represented by Formula 1, so that it can simultaneously have a high refractive index and excellent flexibility, and also contains a repeating unit represented by Formula 3, so that it can be used in the ultraviolet region without an initiator or crosslinker. Crosslinking may also be possible by irradiating a light source.

In addition, the titanium-composite may be preferred because it includes a repeating unit represented by Formula 2 and can have better flexibility and a superior refractive index than copolymers containing repeating units of Formula 1 and Formula 3.

As an embodiment of the present invention, in Formulas 1 to 3, R ₁ , R ₂ and R ₄ are independently hydrogen, methyl or ethyl, and A ₁ and A ₂ are independently a single bond, methylene or ethylene. , R ₃ is straight chain or branched C ₁ -C ₄ alkyl, A ₃ is *-O-*, R ₅ and R ₆ are independently straight chain or branched C ₁ -C ₄ alkyl, n and m are independently integers from 0 to 2, Is ( ) It may be a titanium oxide network structure represented by _n .

The titanium-composite is ( ) By containing the titanium oxide network structure represented by _n , not only can it have a higher refractive index than the conventional high refractive index modified polymer, but also by adjusting the n according to the content of the titanium inorganic compound added during the manufacturing process, the refractive index Adjustment may also be easy. As a result, the color conversion one-dimensional photonic crystal structure including the high refractive index layer can have the advantage of being able to easily control the wavelength range of visible light with optimal reflectance.

As another example, the above Is It can be expressed as, and in the above structure, may mean that the same structure is connected continuously.

As another embodiment, in Formulas 1 to 3, R ₁ is methyl or ethyl, R ₂ and R ₄ are independently hydrogen or methyl, and A ₁ and A ₂ are independently a single bond or methylene. , R ₃ is isobutyl, R ₅ and R ₆ are independently methyl or ethyl, n and m are independently integers from 0 to 1, and A3 may be *-O-* in the same manner as above. , this is not necessarily limited as long as it does not impair the physical properties of the color conversion one-dimensional photonic crystal structure being manufactured.

As one embodiment, the titanium-complex may contain 1 to 50 mol% of the repeating unit represented by Formula 1, based on the total repeating units. As another embodiment, the titanium-composite may contain 1 to 40 mol% or 1 to 30 mol% of the repeating unit represented by Formula 1.

A titanium-composite that satisfies the molar content in the above range may be preferred because it can maintain the excellent flexibility of the polymer structure and have a high refractive index, but this is not necessarily limited.

As one embodiment, the titanium-composite may be represented by the following formula (5).

[Formula 5]

(In Formula 5, a, b and c are rational numbers satisfying a+b+c=1, 0.08≤a≤0.15, 0.02≤b≤0.05 and 0.8≤c≤0.9, is a titanium oxide network structure.)

The titanium-composite is not particularly limited as long as it does not impair the physical properties of the color-changing one-dimensional photonic crystal structure to be manufactured, but in terms of being able to have better harmlessness to the human body, excellent wet stability, and excellent adhesiveness, the formula 5 Being displayed may be more preferable.

As another embodiment, in Formula 5, a, b, and c may be rational numbers satisfying a+b+c=1, 0.08≤a≤0.12, 0.02≤b≤0.03, and 0.85≤c≤0.9, , a titanium-composite that satisfies this may have a higher refractive index and excellent coating processability and may be preferred, but this is not necessarily limited.

In one embodiment of the present invention, the titanium-composite may contain 50 to 80% by weight of titanium oxide network structure, based on the total mass, and in another embodiment, 55 to 80% by weight. %, 60 to 80% by weight, and 65 to 75% by weight.

A titanium-composite containing a titanium oxide network structure in an amount within the above range may be preferred because the titanium oxide network structure and the copolymer structure show excellent dispersibility and form a high refractive index layer, and may have a refractive index of at least 1.5 or more.

As an embodiment of the present invention, the sensitive copolymer may contain repeating units represented by the following formulas 3 and 4, as described above.

[Formula 3]

(Formula 3 is the same as described above.)

[Formula 4]

(In Formula 4, R ₇ is independently hydrogen or straight-chain or branched C ₁ -C ₇ alkyl, and A ₄ is independently a single bond or straight-chain or branched C ₁ -C ₇ alkylene.)

Since the sensitive copolymer has excellent sensitivity to polar substances, a one-dimensional photonic crystal structure containing it not only can detect low relative humidity and trace amounts of aldehyde, but also has excellent color due to a high refractive index difference with the high refractive index layer. Changes can be visible.

The polar material may be recognizable to those skilled in the art, and may be, for example, water vapor, alcohol-based material, aldehyde-based material, carboxylic acid-based material, or alicyclic aldehyde-based material. In the present disclosure, it is sensitive to water vapor and aldehyde-based material. /I want to implement reactivity.

As an embodiment of the present invention, in Formula 4, R ₇ may be hydrogen, methyl, or ethyl, and A ₄ may be straight-chain C ₁ -C ₄ alkylene. As another embodiment, in Formula 3, R ₇ may be methyl or ethyl, and A ₄ may be ethylene or n-butylene.

A sensitive copolymer that satisfies the above structure may be preferred in that it has better relative humidity sensitivity, can have excellent color conversion visibility even with trace amounts of aldehyde-based substances, and can have excellent adhesion to the high refractive index layer. , as long as it does not impair the physical properties of the color conversion one-dimensional photonic crystal structure containing it, this is not limited.

In one embodiment of the present invention, the sensitive copolymer may contain 50 to 99 mol% of the repeating unit represented by Formula 4, based on the total repeating units, and in another embodiment, 60 mol% or more. , it may be 70 mol% or more, 80 mol% or more, or 90 mol% or more.

A sensitive copolymer satisfying the above molar content may be preferred because it can maintain excellent physical properties due to a high degree of cross-linking and at the same time have significantly excellent sensitivity to humidity and sensitivity to aldehyde-based substances, but this is not necessarily limited.

As an embodiment of the present invention, the titanium-complex is not particularly limited, but may have a number average molecular weight of 100,000 to 2,000,000 g/mol, 500,000 to 2,000,000 g/mol, or 1,000,000 to 2,000,000 g/mol.

The number average molecular weight measurement method uses dimethylformamide containing lithium bromide as a mobile phase solvent for the sample, uses gel permeation chromatography (GPC) equipment (Agilent Technologies) including a refractive index change detector, and flows the mobile phase solvent at 40°C. It may be measured under the condition of a speed of 1.0 mL/min.

As an embodiment of the present invention, the sensitive copolymer may be represented by the following formula (6).

[Formula 6]

(In Formula 6, d and e are rational numbers that satisfy d+e=1, 0.9≤d≤0.99, and 0.01≤e≤0.1.)

In one embodiment of the present invention, the sensitive copolymer is not particularly limited, but may have a number average molecular weight of 100,000 to 2,000,000 g/mol, 500,000 to 2,000,000 g/mol, or 1,000,000 to 2,000,000 g/mol.

Since the method for measuring the number average molecular weight of the sensitive copolymer is the same as the method for measuring the number average molecular weight of the titanium composite, detailed description will be omitted.

According to one embodiment of the present invention, the primary photonic crystal structure has a structure in which high refractive index layers and low refractive index response layers are alternately stacked, and includes a high refractive index layer containing a titanium-composite having a higher refractive index than a conventional high refractive index polymer resin. Therefore, it can have excellent sensitivity to polar substances and excellent color change visibility.

As an embodiment of the present invention, the high refractive index layer may have a refractive index of 1.5 to 3.0 for visible light with a wavelength of 633 nm, and a refractive index difference from the low refractive index layer may be 0.07 or more.

Since the high refractive index layer has a chemical bond between the titanium oxide network structure and the copolymer structure, it may have a refractive index in the above range, preferably 1.6 or more, 1.61 or more, more preferably 1.65 or more, and most preferably 1.7 or more. .

That is, due to the significantly higher refractive index of the high refractive index layer, the refractive index difference with the low refractive index response layer may be 0.07 or more, 0.10 or more, preferably 0.15 or more, or 0.20 or more. The upper limit is not limited, but may be 0.30 or less.

As an embodiment of the present invention, in the color conversion one-dimensional photonic crystal structure, the high refractive index layer may have a thickness of 20 to 70 nm, and the low refractive index response layer may have a thickness of 1 to 100 nm. As another embodiment, the thickness of the high refractive index layer may be preferably 230 nm or less, 200 nm or less, 180 nm or less, 170 nm or less, 150 nm or less, or 145 nm or less, and more preferably 100 nm or less, 90 nm or less. It may be ㎚ or less or 80 ㎚ or less, but is not necessarily limited as long as it does not impair the physical properties of the color conversion one-dimensional photonic crystal structure being manufactured.

As an embodiment of the present invention, the color conversion one-dimensional photonic crystal structure may be laminated by alternating high refractive index layers and low refractive response layers in 20 layers or less, preferably 18 layers or less, 17 layers or less, more preferably 15 layers or less. It may be no more than 14 floors, 14 floors or less, 13 floors or less, and at best 12 floors or less, 11 floors or less, or, without limiting the lower limit, at least 6 floors or more, or 8 floors or more.

Since the color conversion one-dimensional photonic crystal structure has a large refractive index difference between the high refractive index layer and the low refractive index response layer having a refractive index of at least 1.5 or more, it can have excellent color change visibility due to the high reflectance even with a smaller number of stacks.

As an embodiment of the present invention, the color conversion one-dimensional photonic crystal structure may have a reflectance of 10% or more as measured by a spectrometer (Ocean Optics USB4000-UV-VIS-ES), preferably 30% or more, 40% or more, or 60% or more. % or more, more preferably 60% or more, 70% or more, and although the upper limit is not limited, it may be 100% or less or less than 100%.

Conventional color conversion one-dimensional photonic crystal structures have to have a refractive index of at least 10% or more by increasing the difference in refractive index of the alternately stacked layers or by stacking a large number of layers, but in the present invention, it has a refractive index that is significantly higher than that of a polymer resin with a general refractive index. By including a titanium-composite, it can have excellent reflectance even when laminated in the same way as a conventional color conversion one-dimensional photonic crystal structure.

As an embodiment of the present invention, the color conversion one-dimensional photonic crystal structure increases the wavelength range of light with maximum reflectance as relative humidity increases, and when exposed to an aldehyde-based material, light with maximum reflectance as relative humidity increases. It may be characterized by a decrease in the growth rate of the wavelength range.

More specifically, the color conversion one-dimensional photonic crystal structure may be characterized by a color change that can be easily recognized by the user according to changes in relative humidity, but no further color change occurs even when exposed to only a trace amount of aldehyde-based material. Through this, aldehyde-based substances can be detected.

In other words, the color conversion one-dimensional photonic crystal structure can have remarkable color conversion visibility due to the swelling behavior of the low-refraction sensitive layer changing due to humidity depending on relative humidity, and furthermore, has excellent reactivity with aldehyde-based materials, Not only can it remove aldehydes, but it can also detect trace amounts of aldehyde-based substances, making it useful as an aldehyde detection sensor.

As an embodiment of the present invention, the color conversion one-dimensional photonic crystal structure may exhibit a color change at a relative humidity of 30% or more.

Since the color conversion one-dimensional photonic crystal structure has excellent sensitivity to moisture, it can have a visible color change even at a relative humidity of 30% or more.

As an embodiment of the present invention, the color conversion one-dimensional photonic crystal structure may be reusable including a reduction reaction.

As described above, the color conversion one-dimensional photonic crystal structure has a distinct color change upon contact with water (steam) and has excellent reactivity with polar compounds, for example, aldehyde-based materials, so that a trace amount of aldehyde can be removed in a short period of time. Just by being exposed to humidity, the color change (change of reflected wavelength) characteristics change significantly, making it easy to see the detected aldehyde-based substances with the naked eye. In addition, even if the color conversion one-dimensional photonic crystal structure reacts with an aldehyde-based material, it can be restored to its initial physical properties through a simple reduction reaction, specifically by immersing it in dilute acid, so it can be used continuously.

One embodiment of the present invention includes preparing a first composition comprising a titanium-complex containing repeating units represented by the following formulas 7 to 9, and a sensitive composition containing the repeating units represented by the following formulas 9 and 10. It may include preparing a second composition containing a copolymer and forming a high refractive index layer and a low refractive index response layer by crossing the first composition and the second composition.

[Formula 7]

[Formula 8]

[Formula 9]

[Formula 10]

(In Formulas 7 to 10, R ₈ , R ₉ , R ₁₁ and R ₁₄ are independently hydrogen or straight-chain or branched C ₁ -C ₇ alkyl, is a titanium oxide network structure, A ₅ , A ₆ and A ₈ are independently a single bond or a straight-chain or branched C ₁ -C ₇ alkylene, and R ₁₀ is hydrogen or a straight-chain or branched C ₁ -C ₇ alkyl, A ₇ is *-O-* or *-NH-*, R ₁₂ and R ₁₃ are independently straight-chain or branched C ₁ -C ₇ alkyl, and n and m are independently of each other It is an integer from 0 to 4.)

Since the titanium-composite and the sensitive copolymer in the method for producing the color-converting one-dimensional photonic crystal structure are the same as described above, detailed description of Formulas 7 to 10 will be omitted.

The titanium-composite further contains a repeating unit represented by Formula 8, so that it not only has a better refractive index, excellent flexibility, and excellent harmlessness to the human body, but also has the formula 7 in the manufacturing method. It may be preferred because it can be formed with better reactivity, but this is not necessarily limited as long as it does not impair the physical properties of the color conversion one-dimensional photonic crystal structure being manufactured.

As one embodiment, the titanium-complex may be prepared in the presence of acid, including a titanium-oxide compound and a precopolymer containing repeating units represented by Formula 8, Formula 9, and Formula 11 below.

[Formula 8]

[Formula 9]

[Formula 11]

(In Formula 11, R ₁₅ may be hydrogen or straight-chain or branched C ₁ -C ₇ alkyl.)

Since R ₁₅ in Formula 11 is the same as R ₈ in Formula 7, detailed description is omitted.

The titanium-oxide compound can be used without limitation as long as it can produce a titanium-composite. For example, It may be expressed as a structure of .

In the above structure, R ₁₆ to R ₁₉ may independently be hydrogen, straight or branched chain C ₁ -C ₇ alkyl, substituted or unsubstituted C ₄ -C ₂₀ cycloalkyl, or substituted or unsubstituted C ₆ -C ₂₀ aryl. In terms of excellent reactivity with the precursor copolymer, R ₁₆ to R ₁₉ may independently be hydrogen or straight-chain or branched C ₁ -C ₇ alkyl, or independently of each other straight-chain C ₁ -C ₇ alkyl. However, this is not necessarily limited.

As an embodiment of the present invention, the titanium-composite production method may involve reacting the precursor copolymer and the titanium-oxide compound in a solvent in a solution state.

The solvent used in the titanium-composite production method can be used without limitation as long as it can dissolve the precursor copolymer, and non-limiting examples include methanol, ethanol, propanol, tetrohydrofuran, dichloroethylene, etc. There may be one or more than one selected.

The solvent used in the titanium-composite manufacturing method may be the same or different from the solvent included in the first composition, which is the first aspect in which the composition prepared by the titanium-composite manufacturing method can be used as the first solvent and titanium. -The titanium-composite obtained by drying the composition prepared by the composite manufacturing method can be manufactured in a second mode by dissolving it again in a solvent and preparing it with the first solvent.

The first embodiment has a simple process and can reduce the volume of manufacturing process equipment, and the second embodiment can be preferred in terms of being able to produce a first composition with higher purity, which is known to those skilled in the art. You can choose according to your needs.

As an embodiment of the present invention, the method of (co)polymerizing the precursor copolymer may be polymerization by solution polymerization or emulsion polymerization, and since this can be recognized by those skilled in the art, detailed description is omitted.

As an embodiment of the present invention, the sensitive copolymer containing the repeating unit represented by Formula 9 and Formula 10 is the same as the sensitive copolymer represented by Formula 3 and Formula 4, and therefore detailed statements are omitted.

As an embodiment of the present invention, the second composition may include a sensitive copolymer dissolved in a solvent, and the solvent may be used without limitation as long as it can dissolve the sensitive copolymer. As a non-limiting example, methanol It may be any one or two or more selected from the group consisting of ethanol, propanol, tetrohydrofuran, and dichloroethylene.

As an embodiment of the present invention, the resin concentration of the first composition and the second composition is not particularly limited as long as it has a coating viscosity, but may be 0.1 to 10 g/ml, and in terms of excellent spin casting processability, it is 0.1 to 5 g/ml or 0.1 to 1 g/ml may be preferred.

In one embodiment of the present invention, the steps of forming the high refractive index layer and the low refractive index response layer can be stacked in an alternating manner to produce a color conversion one-dimensional photonic crystal structure.

The color conversion one-dimensional photonic crystal structure is not particularly limited as long as the high refractive index layer and the low refractive response layer are stacked crossing each other. For example, [high refractive index layer] - [low refractive index sensitive layer] - [high refractive index layer] - [low refractive index sensitive layer] layer] may be laminated, or may be cross-laminated as [low refractive index response layer] - [high refractive index layer] - [low refractive index response layer] - [high refractive index layer].

As an embodiment of the present invention, the high refractive index layer may be formed by coating, drying, and photocuring the first composition.

The first composition coating method can be used without limitation as long as it is a method recognized by those skilled in the art. For example, it can be coated by night coating, spin casting coating, dip coating, drop casting, and roll coating, and can provide a smoother surface and a thinner thickness. Spin casting may be more preferred in terms of forming a high refractive index layer.

The drying process for forming the high refractive index layer can be preferred because it can shorten the time of the photocuring process and prevent the coated first composition from leaving, and the drying temperature is, for example, 40 to 70 ° C. or It may be 40 to 60°C, but is not particularly limited as long as solvent drying is possible and the physical properties of the titanium-composite included are not deteriorated.

Photocuring of the first composition may further include an initiator and a cross-linking agent, but in terms of having a high refractive index and excellent transparency, it may be preferable not to include an initiator or a cross-linking agent.

The titanium-composite included in the first composition may be crosslinked by irradiating a light source in the ultraviolet/visible region with a wavelength of 360 to 400 nm, and the high refractive index layer formed therefrom may have a significantly high refractive index.

The method of forming the low refractive index layer from the second composition may be the same or different from the method of forming the high refractive index layer from the first composition, and this will be described in detail in the following examples, so detailed description will be omitted.

The present disclosure provides an aldehyde detection sensor including the color conversion one-dimensional photonic crystal structure.

The color conversion one-dimensional photonic crystal structure has excellent reflectivity for light of a specific wavelength and is particularly easy to control optical characteristics, so as an example, it can be used as a photonic crystal fiber, a light emitting device, a photovoltaic device, a photonic crystal sensor, or a semiconductor laser etching material. However, in one aspect of the present invention, it can be usefully used as an aldehyde detection sensor by including a color conversion one-dimensional photonic crystal structure with excellent reactivity with aldehyde-based materials.

According to the present disclosure, the color conversion one-dimensional photonic crystal structure has a high refractive index difference between the high refractive index layer and the low refractive index layer, and the low refractive index layer has significantly excellent sensitivity to humidity and polar substances, and has excellent sensitivity by detecting aldehyde-based substances. It was discovered that it has color conversion visibility and can further remove aldehyde-based substances, and the present invention was completed by applying this to an aldehyde detection sensor.

As an embodiment of the present invention, the aldehyde detection sensor may detect a detection object containing more than 1 ppm of formaldehyde and more than 50 ppm of acetaldehyde.

The aldehyde detection sensor shows excellent reactivity with aldehyde compounds and a significant color change depending on humidity, so it has excellent detection ability to detect detection objects containing at least 1 ppm or more formaldehyde, 50 ppm or more acetaldehyde, or mixtures thereof. You can have

As described above, the aldehyde detection sensor can be reused only through a simple reduction process, and can not only detect aldehyde-based substances but also remove them, thereby fundamentally solving various problems caused by aldehyde-based substances.

As an embodiment of the present invention, the aldehyde detection sensor may include various accessory parts such as a semiconductor device, case, inhaler, and warning speaker, and these may be used without limitation as long as they are recognizable to those skilled in the art.

Hereinafter, the present invention will be described in detail with reference to examples. However, these are for explaining the present invention in more detail, and the scope of the present invention is not limited to the following examples.

Additionally, unless otherwise defined, all technical and scientific terms have the same meaning as commonly understood by one of ordinary skill in the art to which the present invention pertains. The terminology used in the description herein is merely to effectively describe particular embodiments and is not intended to limit the invention.

[measurement method]

1. Refractive index measurement

Measurements were made according to ISO 489, and the thickness and refractive index of the high refractive layer and the sensitive layer prepared below were measured using a spectroscopic ellipsometer (HORIBA Scientific, UVISEL).

2. Measurement of titanium oxide network structure content

Using a thermogravimetric analyzer (TA Instruments, Q2000), the weight percent of the titanium oxide network structure contained in the high refractive index layer prepared in the following Examples and Preparation Examples was determined.

3. Reflectance measurements

Using a spectrometer (Ocean Optics USB4000-UV-VIS-ES), the reflectance according to the wavelength of the color-converted one-dimensional photonic crystal structure prepared in the following examples and preparation examples was measured, and the incident angle of the light source was maintained at 0°.

4. Number average molecular weight measurement

To analyze the number average molecular weight of water-insoluble polymers, a gel permeation chromatography (GPC, Agilent Technologies 1260 series) equipped with two column tubes (Agilent PLgel 5 μm MIXED-D x 7.5 mm) and a refractive index change detector was used. For analysis, dimethylformamide solvent containing 0.01 molar concentration of lithium bromide was flowed at 40°C at a rate of 1.0 mL/min, and polymethyl methacrylate was used as a standard sample to determine the number average molecular weight.

To analyze the number average molecular weight of water-soluble polymers, a GPC (Tosoh HLC-8320) equipped with two column tubes (Tosoh TSKgel G5000PWXL-CP and TSKgel G3000PWXL-CP) and a refractive index change detector was used. For analysis, a mixed mobile phase of 0.1 molar concentration of sodium nitrate and 30 volume ratio of acetonitrile maintaining pH 2 was flowed at a rate of 1.0 mL/min at 40°C, and the number average molecular weight was determined using polyethylene glycol as a standard sample.

[Production Example 1]

In a nitrogen environment, 0.96 g of Dopamine acrylamide (DMA), 0.55 g of 4-Benzoylphenyl acrylate (BAP), 4.42 N-Isopropylacrylamide (NIPAM), and 0.07 g of Azobisisobutyronitrile were added to a schlenk flask containing 60 ml of methanol, and incubated with nitrogen gas for 10 minutes. It was bubbling. Afterwards, the Schlenk flask was placed in a silicone oil bath at 70°C and polymerized with sufficient stirring for 14 hours. Afterwards, the reactants in the Schlenk flask were slowly added dropwise to 500 ml of diethyl ether at room temperature and stirred, and the resulting precipitate was obtained through a reduced-pressure filter. . The obtained precipitate was washed with diethyl ether and dried in a vacuum oven at 25°C for 24 hours to obtain copolymer A in the form of a white solid. Afterwards, for further purification, the prepared copolymer A was re-dissolved in 60 ml and slowly added dropwise to 500 ml of diethyl ether while stirring. The resulting precipitate was obtained by vacuum filtering and dried in a vacuum oven at 25°C for 24 hours to form a white solid. High-purity copolymer A was obtained. As a result of GPC and NMR measurements, the number average molecular weight was 69,070 g/mol and the polydispersity index was 1.97. Regarding the total repeating units, N-Isopropylacrylamide repeating units were 87 mol%, Dopamine acrylamide repeating units were 10 mol%, and It was confirmed that 4-Benzoylphenyl acrylate was 3 mol%.

[Production Example 2]

1.66 g of titanium propoxide and 8 ml of 1-propanol were added to a 70 ml vial and stirred for 10 minutes to obtain mixture 1. At the same time, 0.2 g of copolymer A of Preparation Example 1 and 8 ml of 1-propanol were added to a 20 ml vial and ultrasonic dispersion was performed for 10 minutes to obtain Mixture 2. The mixture 2 contained in a 20 mL vial was slowly added dropwise to the 70 mL vial containing the mixture 1 contained in a 70 mL vial and stirred for 10 minutes to obtain mixture 3. Afterwards, 0.02 ml of hydrochloric acid was added to mixture 3 and stirred at room temperature for 10 minutes to obtain mixed solution B containing titanium-complex.

[Production Example 3]

In a nitrogen environment, 0.38 g of 2-Aminoethyl methacrylate hydrochloride, 7 mg of 4-Benzoylphenyl acrylate, and 5 mg of Azobisisobutyronitrile were added to a schlenk flask containing 4 ml of dimethyl sulfoxide and bubbled with nitrogen gas for 10 minutes. Afterwards, the schlenk flask was placed in a silicone oil bath at 70°C and polymerized with sufficient stirring for 12 hours. Afterwards, the reactants in the schlenk flask were transferred to a cellophane tube (molecular weight cutoff 14,000), placed in a beaker containing 2 L of distilled water, and dialyzed at room temperature for 2 days. did. Afterwards, it was freeze-dried for 3 days to obtain copolymer C in the form of a white solid.

As a result of GPC and NMR measurements of the prepared copolymer C, number average molecular weight = 30,276 g/mol, polydispersity index was 1.86, and proton NMR analysis showed that the composition ratio of the copolymer was 2-Aminoethyl methacrylate:4-Benzoylphenyl acrylate. = 98:2 was confirmed.

Afterwards, 0.5 g of copolymer C obtained in Preparation Example 3 was added to 1-neck RBF containing 30 ml of 0.1M NaOH and stirred for 2 hours. Afterwards, the reactant in the 1-neck RBF was transferred to a cellophane tube (molecular weight cutoff 14,000), placed in a beaker containing 2 L of distilled water, and dialyzed for 2 days at room temperature. Afterwards, it was freeze-dried for 3 days to obtain copolymer D in the form of a white solid.

The synthesis of the prepared responsive copolymer D was confirmed through FT-IR and proton NMR analysis, and the number average molecular weight and polydispersity index were the same as those of copolymer C in Preparation Example 3.

[Comparative Manufacturing Example 1]

In a nitrogen environment, 10.00 g of styrene, 0.24 g of 4-Benzoylphenyl acrylate, and 20 mg of Azobisisobutyronitrile were added to a schlenk flask containing 40 ml of 1,4-dioxane and bubbled with nitrogen gas for 10 minutes. Afterwards, the schlenk flask was placed in a silicone oil bath at 70°C and polymerized with sufficient stirring for 12 hours. Afterwards, the reactant in the schlenk flask was slowly added dropwise to 1000 ml of n-hexane at room temperature and stirred, and the resulting precipitate was obtained through a reduced-pressure filter. . The obtained precipitate was washed with n-hexane and dried in a vacuum oven at 25°C for 24 hours to obtain a copolymer in the form of a white solid. Afterwards, for further purification, the prepared copolymer B was re-dissolved in 60 ml and slowly added dropwise to 500 ml of diethyl ether while stirring. The resulting precipitate was obtained by filtering under reduced pressure, and dried in a vacuum oven at 25°C for 24 hours to form a white solid. High-purity copolymer E was obtained. As a result of GPC and NMR measurements of the prepared copolymer E, it was found that the number average molecular weight was 57,759 g/mol and the polydispersity index was 1.57. Regarding the total repeating units, styrene repeating units were 97 mol% and 4-Benzoylphenyl acrylate. It was confirmed that it was 3 mol%.

[Example 1]

To produce a one-dimensional photonic crystal structure, the copolymer-titanium complex mixed solution B of Preparation Example 2 was used as a high refractive index layer composition, and the copolymer D of Preparation Example 4 was dissolved in methanol at a concentration of 0.02 g/mℓ to achieve low refractive index sensitivity. It was used as a layer composition.

The prepared high refractive index composition was coated on a PET/PVC substrate by spin-casting (6000 rpm 2/30s). Afterwards, it was heat-dried in a convection oven at 50°C for 2 minutes, cooled at room temperature for 3 minutes, and cross-linked for 30 seconds using an exposure machine with a UVA (320-400 nm) light source to form a high refractive index layer.

A low refractive index responsive layer was formed on top of the high refractive index layer by using the low refractive index response layer composition prepared above in the same manner as the high refractive index layer manufacturing method. Thereafter, the high refractive index layer and the low refractive index response layer were alternately formed using the same method to produce a color conversion one-dimensional photonic crystal structure with a total of 11 layers.

The color conversion one-dimensional photonic crystal structure prepared was measured using the above method and is shown in Table 1 below.

[Examples 2 to 5]

In Example 1, a color-converting one-dimensional photonic crystal structure was manufactured in the same manner as in Table 1 below, except that the titanium content in the copolymer-titanium composite was different.

The color conversion one-dimensional photonic crystal structure prepared was measured using the above method and is shown in Table 2 below.

[Comparative Example 1]

In Example 2, a color conversion one-dimensional photonic crystal structure was manufactured in the same manner as in Example 2, except that the high refractive index layer was formed only with a polymer composition obtained by dissolving copolymer A of Preparation Example 1 in methanol.

The color conversion one-dimensional photonic crystal structure prepared was measured using the above method and is shown in Table 2 below.

[Comparative Example 2]

In Example 2, a color-converting one-dimensional photonic crystal structure was manufactured in the same manner as in Comparative Preparation Example 1, except that the high refractive index layer was formed only with copolymer E prepared in Comparative Preparation Example 1.

The color conversion one-dimensional photonic crystal structure prepared was measured using the above method and is shown in Table 2 below.

High refractive index layer low refractive index layer refractive index difference Reflectance (%) initial reflection wavelength
(nm) Titanium content
(weight%) thickness
(nm) refractive index thickness
(nm) refractive index Example 1 70 39.6 1.71 69.2 1.52 0.19 60 341 Example 2 50 34.5 1.66 0.14 48 314 Example 3 30 28.6 1.62 0.10 32 292 Example 4 20 25.1 1.59 0.07 10 279 Example 5 80 62.1 1.73 0.21 71 415 Comparative Example 1 - 31 1.53 0.01 One 301 Comparative Example 2 - 41 1.57 0.05 6 339

Looking at Examples 1 to 5 in Table 1, it was confirmed that the reflectance of the color-converting one-dimensional photonic crystal structure was at least 10% or more, preferably 71% or more, depending on the titanium content of the high refractive index layer, and that the reflectance was high enough to be observed with the naked eye. In order to indicate, it is preferable that the titanium content is 50% by weight or more, and when the titanium content is less than 80% by weight, the initial reflection wavelength is formed to be less than 400 nm, so the color conversion one-dimensional photonic crystal sensor has the widest range in the visible light region. This suggests that there may be a range of discoloration.

On the other hand, the color conversion one-dimensional photonic crystal structures of Comparative Examples 1 and 2 had a very narrow refractive index difference, so it was confirmed that the reflectance was less than 6%, and at worst, less than 1%. This suggests that in order for the color conversion one-dimensional photonic crystal structures of Comparative Examples 2 and 3 to have the same reflectance as Examples 1 to 5, the number of cross-stacked layers should be more than 11 layers.

Experimental Example 1. Formaldehyde sensitivity measurement

The color conversion one-dimensional photonic crystal structure prepared in Example 1 was placed in a closed chamber, formaldehyde gas was introduced into the chamber to have a concentration of 1 ppm and 50 ppm, reacted for 20 minutes, and then the chamber was exposed to air and 2 Remaining aldehyde gas is removed by circulating nitrogen for a period of time.

Afterwards, the chamber was closed, the internal relative humidity was adjusted to 30%, 40%, 50%, 60%, 70%, or 80%, and the color change image of the one-dimensional photonic crystal structure was taken and shown in Figure 1 below. At the same time, the spectrometer ( The reflectance of the one-dimensional photonic crystal structure was continuously measured in the 200 to 800 nm wavelength range using an Ocean Optics USB4000-UV-VIS-ES) reflectance meter, and is shown in Figure 2 below.

Experimental Example 2. Measurement of acetaldehyde sensitivity

The color conversion one-dimensional photonic crystal structure prepared in Example 1 was used, and measurements were made in the same manner as in Experimental Example 1, except that 50 ppm or 100 ppm of acetaldehyde was used, and the resulting color conversion image is shown in Figure 3. The reflectance was continuously measured in the wavelength range of 200 to 800 nm and is shown in Figure 4 below.

Referring to Figures 1 and 2 below, when the color conversion one-dimensional photonic crystal structure is not exposed to formaldehyde, the swelling characteristic increases as the relative humidity increases due to the high hydrophilicity of the primary amine group in the low refractive index response layer. It shows a clear color change that gradually changes to red.

And since the color conversion one-dimensional photonic crystal structure does not undergo color conversion when exposed to formaldehyde, it can detect and remove trace amounts of formaldehyde and trace amounts of acetaldehyde. That is, the color conversion one-dimensional photonic crystal structure can generally detect trace amounts of aldehyde in an environment with a relative humidity of 30% or more.

Also, by checking FIGS. 3 and 4, it was confirmed that the color conversion one-dimensional photonic crystal structure was capable of detecting acetaldehyde, similar to when exposed to formaldehyde.

Experimental Example 3. Continuous use measurement

The color conversion one-dimensional photonic crystal structure used in Experimental Examples 1 and 2 was immersed in a 1 M aqueous HCl solution for 30 minutes, washed with distilled water, and dried in a convection oven at 50°C for 2 hours. Thereafter, the dried color conversion one-dimensional photonic crystal structure was placed in a closed chamber and the relative humidity was adjusted to 30%, 40%, 50%, 60%, 70%, and 80%, and the results are shown in Figure 5 below.

Referring to Figure 5 below, it was confirmed that the color conversion one-dimensional photonic crystal structure of Example 2 surprisingly had remarkably excellent humidity sensitivity even when reused by being immersed in an aqueous hydrochloric acid solution, and thus could be continuously recycled.

Experimental Example 4. Sensor detection selectivity measurement

Using the color conversion one-dimensional photonic crystal structure prepared in Example 1, formaldehyde, acetaldehyde, propionaldehyde, butyraldehyde, acetone, dichloromethane, chloroform, ethyl acetate, diethyl ether, benzene, toluene, xylene , and each was immersed in methanol for 20 minutes, then washed with distilled water and dried in a convection oven at 50°C for 2 hours. Afterwards, the chamber was closed, the internal relative humidity was adjusted to 70%, and the reflectance was continuously measured in the 200 to 800 nm wavelength range of the one-dimensional photonic crystal structure using a spectrometer (Ocean Optics USB4000-UV-VIS-ES) reflectance meter, as shown in Figure 6 below. indicated.

Referring to Figure 6 below, except for the case of immersion in formaldehyde and acetaldehyde, the maximum reflectance wavelength in the visible light region is observed around 650 nm at a relative humidity of 70%, which is the color conversion 1 manufactured in Example 1 above. This suggests that the 3D photonic crystal structure has selectivity only for formaldehyde and acetaldehyde.

Therefore, according to one aspect of the present invention, the color conversion one-dimensional photonic crystal structure exhibits excellent reflectivity and visibility due to a high refractive index difference of 0.19 or more between the high refractive index layer and the low refractive index response layer, so it can be used as an aldehyde sensor capable of visual detection, It is sensitive to humidity and contains a low refractive index sensitive layer that causes an irreversible chemical reaction when contacted with formaldehyde and acetaldehyde, making it more useful as an aldehyde detection sensor capable of detecting trace amounts of formaldehyde and acetaldehyde. It can be used easily.

In addition, the color-converting one-dimensional photonic crystal structure according to an aspect of the present invention not only has the above-described high reflectance and sensitive sensitivity to humidity and aldehyde-based materials, but can also maintain excellent sensitivity to humidity and aldehyde-based materials even when continuously reused. It was confirmed that it exists.

As a result, the color conversion one-dimensional photonic crystal structure of the present invention is based on an inexpensive polymer material, and has excellent hardness compared to conventional complex and expensive sensors, is very easy to film, and eliminates formaldehyde and acetaldehyde. Because it can be selectively sensitive, has excellent visibility due to high reflectivity, and can be reused, it can be usefully used as a color conversion sensor to detect aldehyde-based substances.

As described above, in the present invention, the color conversion one-dimensional photonic crystal structure and the aldehyde detection sensor including the same have been described through specific details and limited embodiments, but this is only provided to facilitate a more general understanding of the present invention, and the present invention It is not limited to the above embodiments, and various modifications and variations can be made from these descriptions by those skilled in the art.

Therefore, the spirit of the present invention should not be limited to the described embodiments, and the scope of the patent claims described below as well as all things that are equivalent or equivalent to the scope of the claims will be said to fall within the scope of the spirit of the present invention. .

Claims (17)

A high refractive index layer formed including a titanium-composite containing repeating units represented by the following formulas 1 to 3; and
A low refractive index sensitive layer formed including a sensitive copolymer containing repeating units represented by the following formulas 3 and 4,
A color-converting one-dimensional photonic crystal structure in which the high refractive index layers and the low refractive index response layers are alternately stacked.
[Formula 1]

[Formula 2]

[Formula 3]

[Formula 4]

In Formulas 1 to 4,
R ₁ , R ₂ , R ₄ and R ₇ are independently hydrogen; or straight chain or branched chain C ₁ -C ₇ alkyl,
is a titanium oxide network structure,
A ₁ , A ₂ and A ₄ are independently a single bond; or straight chain or branched chain C ₁ -C ₇ alkylene,
R ₃ is hydrogen; or straight chain or branched chain C ₁ -C ₇ alkyl,
A ₃ is *-O-* or *-NH-*,
R ₅ and R ₆ are independently straight-chain or branched-chain C ₁ -C ₇ alkyl,
n and m are independently integers from 0 to 4. According to clause 1,
In Formulas 1 to 4,
R ₁ , R ₂ , R ₄ and R ₇ are independently hydrogen, methyl or ethyl,
Is ( ) It is a titanium oxide network structure containing _n ,
A ₁ and A ₂ are independently a single bond, methylene or ethylene,
R ₃ is straight or branched C ₁ -C ₄ alkyl,
A ₃ is *-O-*,
R ₅ and R ₆ are independently linear or branched C ₁ -C ₄ alkyl,
A color conversion one-dimensional photonic crystal structure where n and m are independently integers of 0 to 2. According to clause 1,
The titanium-composite is a color-converting one-dimensional photonic crystal structure containing 1 to 50 mol% of the repeating unit represented by Formula 1, based on the total repeating units. According to clause 1,
The sensitive copolymer is a color-converting one-dimensional photonic crystal structure containing 50 to 99 mol% of a repeating unit represented by Formula 4. According to clause 1,
The titanium-composite is represented by the following formula (5), and the sensitive copolymer is represented by the following formula (6).
[Formula 5]

[Formula 6]

In Formula 5, a, b and c are rational numbers satisfying a+b+c=1, 0.08≤a≤0.15, 0.02≤b≤ and 0.8≤c≤0.9, is a titanium oxide network structure,
In Formula 6, d and e are rational numbers that satisfy d+e=1, 0.9≤d≤0.99, and 0.01≤e≤0.1. According to clause 1,
The titanium-composite is a color-converting one-dimensional photonic crystal structure comprising 50 to 80% by weight of a titanium oxide network structure, based on the total mass. According to clause 1,
The color-converting one-dimensional photonic crystal structure is a color-converting one-dimensional photonic crystal structure in which a high refractive index layer and a low refractive response layer are alternately stacked in 20 or less layers. According to clause 1,
The high refractive index layer has a refractive index of visible light with a wavelength of 633 nm of 1.5 to 3.0, and the color conversion one-dimensional photonic crystal structure has a refractive index difference from the sensitive layer of 0.07 or more. According to clause 1,
The thickness of the high refractive index layer is 20 to 70 nm,
A color conversion one-dimensional photonic crystal structure wherein the low refractive index response layer has a thickness of 1 to 200 nm. According to clause 1,
The color conversion one-dimensional photonic crystal structure is a color conversion one-dimensional photonic crystal structure having a maximum reflectance of 10% or more as measured by a spectrometer. According to clause 1,
In the color conversion one-dimensional photonic crystal structure, as relative humidity increases, the wavelength range of light with maximum reflectance increases,
A color-converting one-dimensional photonic crystal structure characterized by a decrease in the rate of increase in the wavelength range of light with maximum reflectance as relative humidity increases when exposed to aldehyde-based materials. According to clause 1,
The color conversion one-dimensional photonic crystal structure is a color conversion one-dimensional photonic crystal structure that changes color at a relative humidity of 30% or more. According to clause 1,
The color conversion one-dimensional photonic crystal structure is characterized in that it includes a reduction reaction and is reusable. An aldehyde detection sensor comprising the color conversion one-dimensional photonic crystal structure of any one of claims 1 to 13. According to clause 14,
The aldehyde detection sensor detects an object containing more than 1 ppm of formaldehyde, more than 50 ppm of acetaldehyde, or a mixture thereof. Preparing a first composition comprising a titanium-complex containing repeating units represented by the following formulas 7 to 9;
Preparing a second composition comprising a sensitive copolymer containing repeating units represented by Formula 9 and Formula 10 below; and
A method of manufacturing a color conversion one-dimensional photonic crystal structure comprising: forming a high refractive index layer and a low refractive index response layer by crossing the first composition and the second composition.
[Formula 7]

[Formula 8]

[Formula 9]

[Formula 10]

In Formulas 7 to 10,
R ₈ , R ₉ , R ₁₁ and R ₁₄ are independently hydrogen; or straight chain or branched chain C ₁ -C ₇ alkyl,
is a titanium oxide network structure,
A ₅ , A ₆ and A ₈ are independently a single bond; or straight chain or branched chain C ₁ -C ₇ alkylene,
R ₁₀ is hydrogen; or straight chain or branched chain C ₁ -C ₇ alkyl,
A ₇ is *-O-* or *-NH-*,
R ₁₂ and R ₁₃ are independently straight-chain or branched-chain C ₁ -C ₇ alkyl,
n and m are independently integers from 0 to 4. According to clause 16,
A method of manufacturing a color-converting one-dimensional photonic crystal structure in which the high refractive index layer is formed by coating, drying, and photocuring the first composition.