CN114456752A - Glue for photonic crystal color label and preparation method thereof - Google Patents

Abstract

The present application relates to the technical field of polymers, and specifically discloses a photonic crystal color label glue and a preparation method thereof. A photonic crystal color label adhesive, comprising the following components in parts by weight: 20-30 parts of thermoplastic copolymer; 20-30 parts of monodisperse microspheres; 10-20 parts of mineral oil; 30-50 parts of tackifying resin; 0.1-0.5 part of antioxidant; the monodisperse microspheres are one or both of silica microspheres and metal compound microspheres, and the particle size of the monodisperse microspheres is 100-400 nm. The photonic crystal color label adhesive of the present application has brilliant structural color, high color brightness, high saturation, and good durability, which effectively improves the shortcomings of the current label color adhesive with poor heat resistance and light resistance.

Description

Glue for photonic crystal color label and preparation method thereof

technical field

The present application relates to the field of polymer technology, and more particularly, to a photonic crystal color label glue and a preparation method thereof.

Background technique

Hot melt adhesive is a kind of plastic adhesive. Its chemical properties remain unchanged under normal use temperature. It is an environmentally friendly chemical and occupies a large proportion in label adhesives. At present, there are many varieties of hot melt adhesives for labels, but the color is single, usually water white, transparent or yellow. With the continuous development of the label industry, the market also has new requirements for the color of hot melt adhesives, in order to achieve the goal of coordinating with the color of the adherend and making the crafts more beautiful and bright.

At present, most of the color label glues on the market choose to add pigments to change the color of the glue, but the heat resistance and light resistance of the pigment pigments are poor, which affects the color persistence of the label glue. Therefore, it is of great significance to develop a non-fading color label glue.

SUMMARY OF THE INVENTION

In order to improve the color persistence of the color label glue and improve the defects of poor heat resistance and light resistance of the current color label glue, the present application provides a photonic crystal color label glue and a preparation method thereof.

The technical principle of the present application is that a photonic crystal is an artificial microcrystal formed by periodic arrangement of two or more dielectric constants (refractive index) media in space. The biggest feature of photonic crystals is that they have a photonic band gap. The existence of the photonic band gap makes the propagation of light produce new behaviors and characteristics. When the light falling in the photonic band gap is in the visible light range, this part of the light cannot pass through the photonic crystal. , but form coherent diffraction on the surface of the photonic crystal. Using the above characteristics of photonic crystal, its structure can be designed so that it can reflect light of corresponding wavelength in the visible light range and show brilliant color. In terms of high reflectivity, high light saturation, high brightness, never fade and so on. Based on the above-mentioned characteristics of photonic crystals and combined with related technologies in the art, the inventor has developed a label glue with high saturation, high brightness and never fading, that is, the photonic crystal color label glue of the present application, and provides The preparation method of the color label glue is presented. The specific scheme of the photonic crystal color label glue and the preparation method thereof of the present application is as follows.

In the first aspect, the application provides a photonic crystal color label glue, which adopts the following technical solutions:

A photonic crystal color label glue, comprising the following components in parts by weight:

20-30 parts of thermoplastic copolymer;

20-30 copies of monodisperse microspheres;

10 to 20 parts of mineral oil;

30 to 50 parts of tackifying resin;

Antioxidant 0.1 to 0.5 parts;

The monodisperse microspheres are one or more of silicon dioxide microspheres, iron tetroxide microspheres, and zinc oxide microspheres, and the particle size of the monodisperse microspheres is 100-400 nm.

By adopting the above technical scheme, by introducing the photonic crystal structure into the hot melt adhesive, the defects of poor heat resistance and light resistance of the currently used hot melt adhesive using pigments as coloring components are improved, and the label adhesive has Brilliant structural color that never fades. The label glue of the present application can show different colors by adjusting the type and particle size of the monodisperse microspheres, and the colors have the advantages of high color brightness and high saturation. In addition, the hot melt adhesive of the present application also has good peel strength, which can meet the application of most label industries.

Preferably, the monodisperse microspheres are silica microspheres, and the particle size of the monodisperse microspheres is 170-220 nm.

By adopting the above technical solution, when the monodisperse microspheres are silica microspheres with a particle size of 170-220 nm, not only the prepared label adhesive has a brilliant and never-fading structural color, but also the label adhesive has Higher peel strength.

Preferably, the thermoplastic copolymer is styrene-isoprene block copolymer, styrene-butadiene block copolymer, hydrogenated styrene-isoprene block copolymer, hydrogenated styrene-butylene A mixture of any two or more of the diene block copolymers.

By adopting the above technical solutions, the present application introduces one or more thermoplastic copolymers mentioned above, since the polymer segments contain styrene rigid blocks, the cohesion of the label adhesive is greatly increased, thereby improving the adhesiveness of the label adhesive. and the durability of the bond.

Preferably, the thermoplastic copolymer is composed of a mixture of styrene-isoprene block copolymer and hydrogenated styrene-butadiene block copolymer, and the styrene-isoprene block copolymer and hydrogenated styrene-isoprene block copolymer are mixed. The weight ratio of the styrene-butadiene block copolymer is 1:1 to 4:3.

By adopting the above technical scheme, the present application compounded the styrene-isoprene block copolymer and the hydrogenated styrene-butadiene block copolymer according to the above ratio to obtain a thermoplastic copolymer, and mixed the thermoplastic copolymer with the tackifier. Resin, antioxidants and other raw materials are prepared together to form a label adhesive. The label adhesive has high peel strength and good adhesion to the substrate, which can meet the application in the field of label adhesives.

Preferably, the thermoplastic copolymer is composed of a mixture of styrene-isoprene block copolymer and hydrogenated styrene-butadiene block copolymer, and the styrene-isoprene block copolymer and hydrogenated styrene-isoprene block copolymer are mixed. The weight ratio of the styrene-butadiene block copolymer was 1:1.

By adopting the above technical scheme, the peel strength and adhesive performance of the label adhesive are further improved.

Preferably, the mineral oil is one or both of naphthenic oil and white mineral oil.

Preferably, the tackifying resin is one or more of rosin resin, hydrogenated rosin resin, C5 petroleum resin, C9 petroleum resin, and C5/C9 copolymer resin.

Preferably, the antioxidant is a sterically hindered phenolic antioxidant.

Preferably, the sterically hindered phenolic antioxidant is one or both of antioxidant 1010 and 2,6-di-tert-butyl-4-methylphenol.

In the second aspect, the application provides a method for preparing a photonic crystal color label glue, which adopts the following technical solutions:

A preparation method of photonic crystal color label glue, comprising the following steps:

S1, controlling the temperature to be 130-135°C, mixing mineral oil, antioxidant and tackifying resin accounting for 60-70% of the total weight of tackifying resin to obtain mixture A;

S2, adding thermoplastic copolymer to mixture A, controlling the stirring speed to be 15-20 r/min, the pressure to be -0.8-1.0 MPa, and pumping for 20-30 min to obtain mixture B;

S3, add the remaining amount of tackifying resin and monodisperse microspheres to mixture B, control the temperature to be 150～155°C, the stirring speed to be 20～30r/min, the pressure to be -0.8～0.9MPa, and the air extraction to be 80～100min, After cooling, the photonic crystal color label glue is obtained.

By adopting the above technical solution, the preparation method of the present application has simple steps, easy realization of conditions, and can be industrialized on a large scale. In addition, adding the tackifying resin in batches to mix in the preparation process can also improve the dispersibility of each component in the label adhesive system, thereby improving various properties of the label adhesive.

To sum up, the present application at least has the following beneficial effects:

In the present application, by introducing the photonic crystal structure into the hot melt adhesive, the prepared photonic crystal label adhesive has brilliant structural color, high color brightness, high saturation, and never fades. In addition, the label adhesive of the present application also has High peel strength, can be used in most label industries.

Detailed ways

The present application will be further described in detail below with reference to the examples.

The raw materials used in each embodiment of the application, except for the following special instructions, are commercially available:

performance test

Test 1: Viscosity Test

Use a viscometer to test the viscosity of the label glue under the conditions of 20rpm and 180°C, repeat the measurement 3 times and take the average value.

Test 2: Ring initial viscosity test

Referring to the test method in GB/T 31125-2014 "Test method for initial adhesion of adhesive tapes, ring method", test the ring initial adhesion of label adhesives.

Test 3: 180° peel force

Refer to Method 1 in GB/T 2792-2014 "Test Method for Peel Strength of Adhesive Tapes" to test the peel strength of the label adhesive.

Test Four: Color Persistence Test

(1) aging the label glue in an oven at 65°C for 7d, and observe its color change;

(2) Expose the label glue to ultraviolet light with an irradiance of 0.89W/m ² at 340nm for 24h, and observe its color change.

Example

Example 1

A photonic crystal color label glue is prepared from thermoplastic copolymer, monodisperse microspheres, mineral oil, tackifying resin and antioxidant. The usage amount of each component is shown in Table 1.

Wherein, the thermoplastic copolymer is composed of styrene-isoprene block copolymer and hydrogenated styrene-butadiene block copolymer in a weight ratio of 4:3;

Monodisperse microspheres are silica microspheres with a particle size of 170 nm;

The mineral oil is naphthenic oil;

The tackifying resin is rosin resin;

The antioxidant is a sterically hindered phenolic antioxidant, specifically antioxidant 1010.

The preparation method of the photonic crystal color label glue of the present embodiment comprises the following steps:

S1, control the temperature to 130 ℃, mix mineral oil, antioxidant and tackifying resin accounting for 60% of the total weight of tackifying resin to obtain mixture A;

S2, adding thermoplastic copolymer to mixture A, controlling the stirring speed to be 15r/min, the pressure to be 1.0MPa, and pumping for 30min to obtain mixture B;

S3, add the remaining amount of tackifying resin and monodisperse microspheres to mixture B, control the temperature to be 150°C, the stirring speed to be 30r/min, the pressure to be -0.8MPa, pump air for 80min, and cool to obtain a photonic crystal color label Use glue.

Example 2-3

A photonic crystal color label glue is different from Example 1 in that the usage amount of each component is shown in Table 1.

The usage amount of each component of embodiment 1-3 and performance testing result are shown in the following table:

Table 1

It can be seen from the data in the above table that the viscosity of the photonic crystal color label adhesive prepared in Examples 1-3 at 20rpm and 180°C is ≥6200cps, the initial ring viscosity is ≥25N/25mm, and the 180° peel force is ≥30N/25mm. After 7d of ℃ aging treatment and 24h exposure to ultraviolet light with an irradiance of 0.89W/m ² at 340nm, the color did not change.

This shows that the photonic crystal structure is introduced into the label glue in the present application, so that the label glue has a brilliant and never-fading structural color, effectively improving the defects of poor heat resistance and light resistance of the current pigment system glue, and the label The adhesive also has high viscosity, initial ring tack and peel strength, and can be used in most label industries.

Examples 4-7

A photonic crystal color label glue is different from Example 3 in that the particle size of the monodisperse microspheres is different, as shown in Table 2.

The particle diameter of embodiment 3,4-7 monodisperse microsphere and performance detection result are as shown in the following table:

Table 2

It can be seen from the data in the above table that the viscosity of the photonic crystal color label glue prepared in Example 4-7 at 20rpm and 180°C is ≥6000cps, the initial ring viscosity is ≥24N/25mm, and the 180° peeling force is ≥31N/25mm. After 7d of ℃ aging treatment and 24h exposure to ultraviolet light with an irradiance of 0.89W/m ² at 340nm, the color did not change.

Examples 9-10

A photonic crystal color label glue is different from Example 4 in that the types of monodisperse microspheres are different, as shown in Table 3.

Embodiment 4, 9-10 monodisperse microsphere species and performance testing result are shown in the following table:

table 3

It can be seen from the data in the above table that the viscosity of the photonic crystal color label glue prepared in Examples 9-10 at 20rpm and 180°C is ≥6400cps, the initial ring viscosity is ≥26N/25mm, and the peeling force at 180° is ≥33N/25mm. After 7d of ℃ aging treatment and 24h exposure to ultraviolet light with an irradiance of 0.89W/m ² at 340nm, the color did not change.

Example 11

A photonic crystal color label glue, the difference from Example 4 is that the thermoplastic copolymer is composed of a styrene-isoprene block copolymer and a hydrogenated styrene-butadiene block copolymer in a weight ratio of 1 :1 mixed composition.

The performance testing results of embodiment 4 and 11 are shown in the following table:

Table 4

It can be seen from the data in the above table that the viscosity of the photonic crystal color label adhesive prepared in Example 11 at 20rpm and 180°C can reach 6700cps, the initial ring viscosity can reach 29N/25mm, the peeling force at 180° can reach 36N/25mm, and After 65 ℃ of aging treatment for 7d, 340nm irradiance 0.89W/m ² UV exposure for 24h, no change in color.

Comparative ratio

Comparative Example 1

An adhesive for color labels, which is different from Example 1 in that the same weight of pigment is used instead of monodisperse microspheres. Among them, the pigment is purple, which is collected from Guangzhou Xianrenhui International Trade Co., Ltd.

Comparative Example 2-3

A color label glue, the difference from Example 1 is that the particle size of the monodisperse microspheres is different, as shown in Table 5.

Embodiment 1 and comparative example 1-3 monodisperse microsphere particle size and performance detection result are as shown in the following table:

table 5

It can be seen from the data in the above table that the viscosity of the label adhesive prepared in Comparative Examples 1-3 at 20rpm and 180°C is only 5200-5800cps, the initial ring viscosity is only 20-23N/25mm, and the peeling force at 180° is only 26- 28N/25mm, aged at 65°C for 7 days, and exposed to UV light with an irradiance of 0.89W/m ² at 340nm for 24 hours, the color of the adhesive used in the label of Comparative Example 1 changed significantly, and there was obvious fading. The label glue of Comparative Example 2-3 is a colorless colloid after preparation, because the microspheres with a particle size below 80 nm are colorless, the diffracted light is ultraviolet light, and the diffracted light greater than 400 nm is infrared, which cannot express color.

This shows that the photonic crystal color label adhesive of the embodiment of the present application has brilliant structural color, high color brightness, high saturation, and never fades, and has high viscosity, annular initial tack and peel strength, and can be applied in most label industries.

This specific embodiment is only an explanation of the application, and it does not limit the application. Those skilled in the art can make modifications to the embodiment without creative contribution as needed after reading this specification, but as long as the rights of the application are All claims are protected by patent law.

Claims (10)

1. a photonic crystal color label glue is characterized in that, comprises the component of following parts by weight: 20-30 parts of thermoplastic copolymer; 20-30 copies of monodisperse microspheres; 10 to 20 parts of mineral oil; 30-50 parts of tackifying resin; Antioxidant 0.1～0.5 part; The monodisperse microspheres are one or more of silicon dioxide microspheres, iron tetroxide microspheres, and zinc oxide microspheres, and the particle size of the monodisperse microspheres is 100-400 nm. 2 . The photonic crystal color label glue according to claim 1 , wherein the monodisperse microspheres are silica microspheres, and the particle size of the monodisperse microspheres is 170-220 nm. 3 . 3. The photonic crystal color label glue according to claim 1, wherein the thermoplastic copolymer is a styrene-isoprene block copolymer, a styrene-butadiene block copolymer, a hydrogenated A mixture of any two or more of styrene-isoprene block copolymer, hydrogenated styrene-butadiene block copolymer. 4. The photonic crystal color label glue according to claim 3, wherein the thermoplastic copolymer is mixed by a styrene-isoprene block copolymer and a hydrogenated styrene-butadiene block copolymer composition, the weight ratio of the styrene-isoprene block copolymer and the hydrogenated styrene-butadiene block copolymer is 1:1-4:3. 5. The photonic crystal color label glue according to claim 3 or 4, wherein the thermoplastic copolymer is composed of a styrene-isoprene block copolymer and a hydrogenated styrene-butadiene block copolymer The weight ratio of the styrene-isoprene block copolymer and the hydrogenated styrene-butadiene block copolymer is 1:1. 6 . The photonic crystal color label glue according to claim 1 , wherein the mineral oil is one or both of naphthenic oil and white mineral oil. 7 . 7. photonic crystal color label glue according to claim 1, is characterized in that, described tackifying resin is a kind of in rosin resin, hydrogenated rosin resin, C5 petroleum resin, C9 petroleum resin, C5/C9 copolymer resin or more. 8 . The photonic crystal color label glue according to claim 1 , wherein the antioxidant is a sterically hindered phenolic antioxidant. 9 . 9. The photonic crystal color label glue according to claim 8, wherein the sterically hindered phenolic antioxidant is antioxidant 1010, 2,6-di-tert-butyl-4-methylphenol one or both of them. 10. the preparation method of any described photonic crystal color label glue of claim 1-7, is characterized in that, comprises the following steps: S1, controlling the temperature to be 130-135°C, mixing mineral oil, antioxidant and tackifying resin accounting for 60-70% of the total weight of tackifying resin to obtain mixture A; S2, adding thermoplastic copolymer to mixture A, controlling the stirring speed to be 15-20 r/min, the pressure to be -0.8-1.0 MPa, and pumping for 20-30 min to obtain mixture B; S3, add the remaining amount of tackifying resin and monodisperse microspheres to mixture B, control the temperature to be 150～155°C, the stirring speed to be 20～30r/min, the pressure to be -0.8～0.9MPa, and the air extraction to be 80～100min, After cooling, the photonic crystal color label glue is obtained.