Sensitive liquid crystalline polymeric material suitable for reflective hologram recording and the preparing method thereof

1. A holographic photosensitive paint, comprising a photosensitive polymeric paint and a suitable solvent, wherein the photosensitive polymeric paint comprises the following components in weight percent:

film forming gent

  20%-80%

azobenzene liquid crystal polymer

  5%-28%

polymerizable monomer

  10%-42%

photoinitiator

 0.5%-7%

photosensitizer

0.05%-2%

wherein the solid content of the holographic photosensitive paint is 5%-50% by weight.

2. The holographic photosensitive paint of claim 1 , wherein the photosensitive polymeric paint comprises the following components in weight percent:

film forming agent

 30%-70%

azobenzene liquid crystal polymer

  6%-25%

polymerizable monomer

 12%-38%

photoinitiator

2.0%-7.0%

photosensitizer

0.5%-2.0%.

3. The holographic photosensitive paint of claim 1 , wherein the film forming agent is selected from the group consisting of poly(methylmethacrylate), poly cellulose acetate butyrate, cellulose acetate butyrate-ethyl vinyl ether copolymer, a blend of polyvinyl butyral and cellulose acetate, polyvinylacetate-butyl acrylate-acrylic acid ternary copolymer, polystyrene acrylonitrile, and a blend of one or more of the preceding polymers and a fluorine-containing polymer, wherein the fluorine-containing polymer is selected from the group consisting of trifluorochloroethylene-acetate vinyl ether copolymer and tetrafluoroethylene-ethyl vinyl ether copolymer;

the polymerizable monomer is selected from the group consisting of acrylic acid, methyl methacrylate, butyl methacrylate, trimethylolpropane triacrylate, diacetone acrylamide, and diacrylate of ethoxylated bisphenol A; wherein when two or more monomers are selected, the weight ratio is 1:0.4-0.9;

the photoinitiator is selected from the group consisting of 2,4,6-triphenyl imidazolyl dimer, dibenzoyl and 2,2-dimethyl-2-phenyl acetophenone;

the photosensitizer is selected from the group consisting of erythrosin B, diethylamino-benzylidene cyclopentanone, Michler's ketone and 1,3,3-trimethyl-2-[5-(1,3,3-trimethyl-2-indolidene)-1,3-pentadiene]indole iodide;

the solvent is a blended solvent of butanone/dichloromethane/methanol, the weight ratio of which is 4-6:0.5-1.5:0.5-1.5.

4. The holographic photosensitive paint of claim 1 , wherein the azobenzene liquid crystal polymer is selected from p-aminoazobenzene poly(methyl acrylate) and p-aminoazobenzene poly(butyl acrylate).

5. The holographic photosensitive paint of claim 1 , wherein the photosensitive polymeric paint further comprises a plasticizer in an amount of 0.5-3% and/or an UV absorber in an amount of 0.1-1% and/or non-ionic surfactant in an amount of 0.1-1% based on the total weight of the photosensitive polymeric paint;

the plasticizer is selected from the group consisting of phthalates, alkyl dioic ester, polyethyleneglycol carboxylic ester and diethyl sebacate;

the UV absorber is selected from the group consisting of 2-hydroxyl-4-methoxybenzophenone and 2-(2H-benzotriazole-2)-4,6-di(1-methyl-1-phenylethyl)phenol;

the non-ionic surfactant is selected from the group consisting of polyethylene glycol, methoxy polyethylene glycol and fluoric surfactant.

6. A photosensitive polymeric film capable of recording the reflection hologram, comprising a base film, a buffer layer coated on one side of the base film, a photosensitive polymer coating layer formed of the holographic photosensitive paint according to claim 1 coated on the other side of the buffer layer, and a surface protective film covering the surface of the photosensitive polymer coating layer.

7. The photosensitive polymeric film capable of recording the reflection hologram of claim 6 , wherein the photosensitive polymer coating layer, after being dried, has a thickness of 3-50 μm.

8. The photosensitive polymeric film capable of recording reflection hologram of claim 6 , wherein the base film has a thickness of 20-100 μm and comprises a material selected from the group consisting of PVC, PET and BOPP;

the buffer layer is a link layer between the photosensitive polymer coating layer and the base film, the buffer layer comprising a photo-curing coating layer of vinyl acetate-acrylic ester copolymer, vinylidene chloride-styrene-vinyl acetate copolymer, or acrylic ester, the buffer layer having a reflective index which is substantially the same as that of the base film and the buffer layer having a thickness of 1-2 μm;

the surface protective film is made of a base material that has a release coating, and the thickness of the surface protective film is 16-23 μm.

9. A reflection hologram film, wherein an interference fringe of a holographic image or double color-changing image is recorded in the photosensitive polymer coating layer of the photosensitive polymeric film capable of recording the reflection hologram according to claim 8 .

10. A method for preparing the reflection hologram film of claim 9 , comprising the following steps:

(1) adding film forming agent, azobenzene liquid crystal polymer, polymerizable monomer, photoinitiator and photosensitizer into a solvent in proportion in darkness or under a red light, and stirring to obtain the photosensitive paint;

(2) coating the buffer layer on a first side of the base film, then coating in darkness or under a red light the photosensitive paint obtained in step (1) on the other side of the base film on which the buffer layer has been coated, drying at 65-75° C. for 1-5 minutes, covering the side of the base film on which the photosensitive paint has been coated with the protective film after drying, then passing through a 0.5-5.0 T magnetic field with a speed of 1-3 m/min at room temperature to orient the azobenzene liquid crystal polymer, so as to obtain the photosensitive polymeric film material; and

(3) uncovering the protective film of the product obtained in step (2), recording a holographic image on the photosensitive polymeric film material by a reflection hologram recording method, totally subjecting the film to UV and visible light on a UV-curing machine, and then heating at 120° C. for 2-50 minutes to obtain the reflection hologram film.

11. The method of claim 10 , wherein the wavelength of the red light is greater than 600 nm, and the reflection hologram recording method uses a laser light source in which the wavelength of the laser light source is 514.5 nm or 532 nm, the light intensity is 60-110 mw/cm 2 , and the exposure time is 0.1-1.0 s.

12. The method of claim 10 , further comprising simultaneously adding plasticizer and/or UV absorber and/or surfactant in step (1).