Fingerprint-like film with adjustable surface protrusion patterns and its preparation method and application

Abstract

The present invention provides a fingerprint-like film with adjustable surface raised patterns, which is made of a chiral compound S811, an ionic liquid, an acrylic ester liquid crystal polymerizable monomer, a photoinitiator 651 and a nematic liquid crystal, and also provides a preparation method and application. The fingerprint-like film with adjustable surface raised patterns prepared by the present invention is non-replicable and can be used in the fields of anti-counterfeiting, optical devices, data storage and information encryption, decoration, etc.

Description

Technical Field

[0001] The invention belongs to the technical field of fingerprint-like films, and in particular relates to a fingerprint-like film with adjustable surface raised patterns, and a preparation method and application thereof. Background Art

[0002] The various patterns of fingerprints have been used to distinguish different people. Film materials with fingerprint structures can also be used for such functions. At present, the development of fingerprint pattern films often has the risk of being forged or imitated, which threatens the security of fingerprint recognition systems, especially in the absence of other verification mechanisms. This preparation method can prevent being placed, and the generation of fingerprints is random and cannot be prevented after generation, which has the characteristics of security. Summary of the invention

[0003] The technical problem to be solved by the present invention is to provide a fingerprint-like film with adjustable surface raised patterns and a preparation method and application thereof in view of the deficiencies of the above-mentioned prior art. The fingerprint-like film with adjustable surface raised patterns is non-replicable and can be used in the fields of anti-counterfeiting, optical devices, data storage and information encryption, decoration, etc.

[0004] In order to solve the above technical problems, the technical solution adopted by the present invention is: a fingerprint-like film with adjustable surface raised patterns, which is made of the following raw materials in mass fraction: chiral compound S811 0.1% to 10%, ionic liquid 0.1% to 1%, acrylate liquid crystal polymerizable monomer 3% to 20%, photoinitiator 651 0.01% to 0.5%, and the balance is nematic liquid crystal;

[0005] The structural formula of the chiral compound S811 is

[0006]

[0007] The structural formula of the ionic liquid is

[0008] The structural formula of the acrylic ester liquid crystal polymerizable monomer is polymerizable monomer a, polymerizable monomer b, polymerizable monomer c, polymerizable monomer d, polymerizable monomer e or polymerizable monomer f;

[0009] The structural formula of the polymerizable monomer a is:

[0010]

[0011] The structural formula of the polymerizable monomer b is:

[0012]

[0013] The structural formula of the polymerizable monomer c is:

[0014]

[0015] The structural formula of the polymerizable monomer d is:

[0016]

[0017] The structural formula of the photoinitiator 651 is:

[0018] The present invention also provides a method for producing the above-mentioned film with adjustable surface protrusion patterns similar to fingerprints, the method comprising:

[0019] The chiral compound S811, ionic liquid, acrylic liquid crystal polymerizable monomer, photoinitiator 651 and nematic liquid crystal are mixed, mixed and shaken at a temperature of 40°C to 120°C, poured into the gap formed by two glass substrates, cooled in a water environment, and irradiated for 1min to 30min under ultraviolet light conditions with an intensity of 0.01mw to 30mw to obtain a fingerprint-like film with adjustable surface raised patterns.

[0020] The present invention also provides the application of the fingerprint-like film with adjustable surface raised patterns prepared by the above method. The fingerprint-like film with adjustable surface raised patterns is used for anti-counterfeiting, optical devices, data storage and information encryption, and decoration.

[0021] Compared with the prior art, the present invention has the following advantages:

[0022] The fingerprint-like film with adjustable surface raised patterns prepared by the present invention is non-replicable and can be used in the fields of anti-counterfeiting, optical devices, data storage and information encryption, decoration, etc.

[0023] The present invention is further described in detail below with reference to the accompanying drawings and embodiments. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a polarizing microscope image of the fingerprint-like film with adjustable surface protrusion patterns prepared at 40° C. in Example 1 of the present invention.

[0025] Figure 2 This is a polarizing microscope image of the fingerprint-like film with adjustable surface protrusion patterns prepared at 80° C. in Example 1 of the present invention.

[0026] Figure 3 This is a polarizing microscope image of the fingerprint-like film with adjustable surface protrusion patterns prepared at 120° C. in Example 1 of the present invention. DETAILED DESCRIPTION

[0027] The raw material information used in the following examples is as follows:

[0028] Chiral compound S811 was purchased from Beijing Bayi Space-Time Liquid Crystal Technology Co., Ltd., CAS 250777-66-3.

[0029] The ionic liquid (1-hexadecyl-3-methylimidazolium bromide) was purchased from Shanghai Bid Pharmaceutical Technology Co., Ltd., CAS 132361-22-9.

[0030] Nematic liquid crystal was purchased from slc1717 (Shijiazhuang Yongsheng Huaqing Liquid Crystal Co., Ltd., o =1.519,n e =1.720,at298k).

[0031] Photoinitiator 651 was purchased from Shanghai Beilu Chemical Technology Co., Ltd., CAS 24650-42-8. It is a highly efficient UV photoinitiator used to initiate UV polymerization reactions of unsaturated prepolymer systems.

[0032] Example 1

[0033] The fingerprint-like film with adjustable surface raised lines of this embodiment is made of the following raw materials by mass fraction: chiral compound S8110.1%, ionic liquid (1-hexadecyl-3-methylimidazolium bromide) 1%, acrylate liquid crystal polymerizable monomer 20%, photoinitiator 6510.01%, and the balance is nematic liquid crystal;

[0034] The structural formula of the chiral compound S811 is

[0035]

[0036] The structural formula of the ionic liquid is

[0037] The ionic liquid has a certain degree of compatibility with liquid crystals and is hydrophobic, so it will stand on the surface of the substrate, and the long chains help the liquid crystal molecules to align perpendicularly to the substrate.

[0038] The structural formula of the acrylic acid ester liquid crystal polymerizable monomer is

[0039] The acrylic ester liquid crystal polymerizable monomer was purchased from Nanjing Xinyao Technology Co., Ltd., CAS1333496-32-4;

[0040] The acrylic ester liquid crystal polymerizable monomer undergoes UV polymerization reaction of an unsaturated prepolymerization system, thereby increasing the stability of the film.

[0041] The structural formula of the photoinitiator 651 is:

[0042] This embodiment also provides a method for producing the above-mentioned fingerprint-like film with adjustable surface protrusion patterns, the method comprising:

[0043] The chiral compound S811, ionic liquid, acrylic liquid crystal polymerizable monomer, photoinitiator 651 and nematic liquid crystal are mixed, mixed and shaken at a temperature of 40°C, and poured into the gap formed by two glass substrates. The specific method is as follows: the left and right sides of the two glasses are separated by a polyester film to obtain a uniform thickness, and the sample is poured in by capillary action; then after cooling in a water environment, it is irradiated with ultraviolet light with an intensity of 0.01mw for 30 minutes to obtain a fingerprint-like thin film with an adjustable surface raised texture with a thickness of 20μm.

[0044] In this embodiment, nematic liquid crystal and chiral compound S811 are the basis for producing fingerprints, but even with these two materials, if the film is made directly without any treatment, fingerprints will not appear, but other lines will appear. After adding ionic liquid and cooperating with heat treatment, fingerprints can appear. At the same time, adding acrylic liquid crystal polymerizable monomers and photoinitiator 651 can increase the stability of the film.

[0045] According to the preparation method of this embodiment, the difference in preparation is that the heat treatment temperature is different, and the temperature of the film preparation with adjustable surface protrusion lines is adjusted to 40°C ( Figure 1 ) becomes 80℃( Figure 2 )、120℃( Figure 3 ) to prepare a film with adjustable surface convex patterns similar to fingerprints.

[0046] like Figure 1-3 As shown, the fingerprint pattern of the film with adjustable surface raised patterns prepared at different heat treatment temperatures can be changed, which can achieve temperature anti-counterfeiting. The regularity of the fingerprint patterns at different temperatures is different, but the patterns appear randomly. In addition, even under the same temperature conditions, the fingerprints of the prepared films are different, so they are not imitative and are safer. The fingerprint spacing can be adjusted by adjusting the ratio of the chiral compound S811 to the nematic phase liquid crystal.

[0047] In this embodiment, the fingerprint-like surface raised patterns prepared at different heat treatment temperatures have different adjustable film fingerprint patterns, and a series of fingerprint patterns with non-replicable anti-counterfeiting functions can be produced.

[0048] While ensuring the uniqueness of the fingerprint lines, the spacing between the fingerprint lines can be adjusted by adjusting the ratio of the chiral compound S811 to the nematic phase liquid crystal. The higher the content of the chiral compound S811, the larger the spacing.

[0049] The texture can achieve temperature anti-counterfeiting. In the process of film preparation, when the temperature rises above a certain point, the temperature changes, and the texture of the film prepared later will change. The obvious change is that when the temperature rises above the phase transition point of the liquid crystal, the texture will change after the temperature drops.

[0050] Example 2

[0051] The fingerprint-like film with adjustable surface raised lines of this embodiment is made of the following raw materials by mass fraction: chiral compound S81110%, ionic liquid (1-hexadecyl-3-methylimidazolium bromide) 0.1%, acrylate liquid crystal polymerizable monomer 3%, photoinitiator 6510.5%, and the balance is nematic liquid crystal;

[0052] The structural formula of the chiral compound S811 is

[0053]

[0054] The structural formula of the ionic liquid is

[0055] The structural formula of the acrylic acid ester liquid crystal polymerizable monomer is

[0056] The acrylic ester liquid crystal polymerizable monomer was purchased from Nanjing Xinyao Technology Co., Ltd., CAS 132900-75-5;

[0057] The acrylic ester liquid crystal polymerizable monomer is used to generate UV polymerization reaction of unsaturated prepolymer system to increase the stability of the film;

[0058] The structural formula of the photoinitiator 651 is:

[0059] This embodiment also provides a method for producing the above-mentioned fingerprint-like film with adjustable surface protrusion patterns, the method comprising:

[0060] The chiral compound S811, ionic liquid, acrylic liquid crystal polymerizable monomer, photoinitiator 651 and nematic liquid crystal are mixed, mixed and shaken at a temperature of 80°C, and poured into the gap formed by two glass substrates. The specific method is as follows: the left and right sides of the two glasses are separated by a polyester film to obtain a uniform thickness, and the sample is poured in by capillary action; then after cooling in a water environment, it is irradiated with ultraviolet light with an intensity of 30mw for 1 minute to obtain a fingerprint-like surface raised texture adjustable film with a thickness of 20μm.

[0061] Example 3

[0062] The fingerprint-like film with adjustable surface raised lines of this embodiment is made of the following raw materials by mass fraction: chiral compound S8113%, ionic liquid (1-hexadecyl-3-methylimidazolium bromide) 0.5%, acrylate liquid crystal polymerizable monomer 5%, photoinitiator 6510.1%, and the balance is nematic liquid crystal;

[0063] The structural formula of the chiral compound S811 is

[0064]

[0065] The structural formula of the ionic liquid is

[0066] The structural formula of the acrylic acid ester liquid crystal polymerizable monomer is

[0067] The acrylic ester liquid crystal polymerizable monomer was purchased from Nanjing Xinyao Technology Co., Ltd., CAS 125248-71-7;

[0068] The structural formula of the photoinitiator 651 is:

[0069] This embodiment also provides a method for producing the above-mentioned fingerprint-like film with adjustable surface protrusion patterns, the method comprising:

[0070] The chiral compound S811, ionic liquid, acrylic liquid crystal polymerizable monomer, photoinitiator 651 and nematic liquid crystal are mixed, mixed and shaken at a temperature of 120°C, and then poured into the gap formed by two glass substrates. The specific method is as follows: the left and right sides of the two glasses are separated by a polyester film to obtain a uniform thickness, and the sample is poured in by capillary action; then after cooling in a water environment, it is irradiated with ultraviolet light with an intensity of 20mw for 10 minutes to obtain a fingerprint-like surface raised texture adjustable film with a thickness of 20μm.

[0071] Example 4

[0072] The fingerprint-like film with adjustable surface raised lines of this embodiment is made of the following raw materials by mass fraction: chiral compound S8118%, ionic liquid (1-hexadecyl-3-methylimidazolium bromide) 0.3%, acrylate liquid crystal polymerizable monomer 15%, photoinitiator 6510.05%, and the balance is nematic liquid crystal;

[0073] The structural formula of the chiral compound S811 is

[0074]

[0075] The structural formula of the ionic liquid is

[0076] The structural formula of the acrylic acid ester liquid crystal polymerizable monomer is

[0077] The acrylic ester liquid crystal polymerizable monomer was purchased from Nanjing Xinyao Technology Co., Ltd., CAS 164590-18-5;

[0078] The structural formula of the photoinitiator 651 is:

[0079] This embodiment also provides a method for producing the above-mentioned fingerprint-like film with adjustable surface protrusion patterns, the method comprising:

[0080] The chiral compound S811, ionic liquid, acrylic liquid crystal polymerizable monomer, photoinitiator 651 and nematic liquid crystal are mixed, mixed and shaken at a temperature of 100°C, and then poured into the gap formed by two glass substrates. The specific method is as follows: the left and right sides of the two glasses are separated by a polyester film to obtain a uniform thickness, and the sample is poured in by capillary action; after cooling in a water environment, it is irradiated with ultraviolet light at an intensity of 20mw for 15min to obtain a fingerprint-like thin film with adjustable surface raised patterns with a thickness of 20μm.

[0081] Example 5

[0082] The fingerprint-like films with adjustable surface protrusion patterns prepared in Examples 1-4 are used for anti-counterfeiting, optical devices, data storage and information encryption, and decoration. The specific application scenarios are as follows:

[0083] (1) Anti-counterfeiting technology

[0084] Application scenarios: The complex optical properties of fingerprint textures can be used to generate unique micropatterns for the manufacture of anti-counterfeiting labels and high-security authentication marks.

[0085] Mechanism: The reflected light from fingerprint texture is wavelength selective and can exhibit unique optical effects that are difficult to replicate.

[0086] (2) Optical devices

[0087] Application scenarios: In tunable optical devices and optical filters, it is used to dynamically control the reflection and transmission of light.

[0088] Mechanism: By changing the pitch of the fingerprint texture, the polarization direction and wavelength response of light can be adjusted, thereby achieving dynamic optical regulation.

[0089] (3) Sensor

[0090] Application scenarios: Fingerprint textures are used in environmental sensors to detect temperature, pressure or chemical stimuli.

[0091] Mechanism: Fingerprint texture is sensitive to external stimuli (such as temperature changes), and structural changes are manifested through optical signals for instant detection.

[0092] (4) Decoration and art design

[0093] Application scenarios: Use the visual effects of fingerprint textures to create decorative materials or artworks.

[0094] Mechanism: The colorful reflections of light and the unique spiral pattern are attractive and are used in high-end decorative materials and innovative art designs.

[0095] (5) Data storage and information encryption

[0096] Application scenario: Use the uniqueness of fingerprint texture to design high-security devices for information encryption and data storage.

[0097] Mechanism: The structure of the fingerprint can be used as a physically unclonable function (PUF) to store secure information that can only be read by specific optical devices.

[0098] The above is only a preferred embodiment of the present invention and does not limit the present invention in any way. Any simple modification, change and equivalent change made to the above embodiment according to the technical essence of the invention still falls within the protection scope of the technical solution of the present invention.

Claims

1. A film with adjustable fingerprint-like surface protrusions, characterized in that: The invention is prepared from the following raw materials in mass fractions: 0.1% to 10% of chiral compound S811, 0.1% to 1% of ionic liquid, 3% to 20% of acrylate liquid crystal polymerizable monomer, 0.01% to 0.5% of photoinitiator 651, and the balance is nematic liquid crystal; The structural formula of the chiral compound S811 is The structural formula of the ionic liquid is The structural formula of the acrylic ester liquid crystal polymerizable monomer is polymerizable monomer a, polymerizable monomer b, polymerizable monomer c, polymerizable monomer d, polymerizable monomer e or polymerizable monomer f; The structural formula of the polymerizable monomer a is: The structural formula of the polymerizable monomer b is: The structural formula of the polymerizable monomer c is: The structural formula of the polymerizable monomer d is: The structural formula of the photoinitiator 651 is:

2. A method for preparing the fingerprint-like film with adjustable surface protrusion patterns as claimed in claim 1, characterized in that: The method is: The chiral compound S811, ionic liquid, acrylic liquid crystal polymerizable monomer, photoinitiator 651 and nematic liquid crystal are mixed, mixed and shaken at a temperature of 40°C to 120°C, poured into the gap formed by two glass substrates, cooled in a water environment, and irradiated for 1min to 30min under ultraviolet light conditions with an intensity of 0.01mw to 30mw to obtain a fingerprint-like film with adjustable surface raised patterns.

3. An application of a film with adjustable surface protrusion patterns similar to fingerprints prepared by the method of claim 2, characterized in that: The fingerprint-like film with adjustable surface raised patterns is used for anti-counterfeiting, optical devices, data storage and information encryption, and decoration.

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