CN-122018051-A - Composite optical film with intrinsic hydrophobicity and preparation method thereof

CN122018051ACN 122018051 ACN122018051 ACN 122018051ACN-122018051-A

Abstract

The invention discloses a composite optical film with intrinsic hydrophobicity and a preparation method thereof. The composite optical film comprises a substrate and an optical film system arranged on the substrate, wherein the optical film system comprises an organic-inorganic hybrid hydrophobic film layer. The organic-inorganic hybrid hydrophobic membrane layer is composed of an inorganic porous framework and an organic nano disperse phase dispersed in the inorganic porous framework, wherein the inorganic porous framework has microscopic porosity which gradually increases from the inner side surface to the outer side surface. The organic nanometer disperse phase is filled in the microscopic pores in situ to form a space embedded structure with gradually increased distribution concentration gradient. The invention utilizes covalent bonding and space embedding of the organic component and the inorganic framework to obviously improve the mechanical wear resistance and the hydrophobic antifouling life of the film. The preparation method adopts a dual-source codeposition combined with a pulsed ion beam technology, and realizes the accurate construction of the gradient distribution structure by dynamically modulating the deposition rate ratio and the pulse energy phase.

Inventors

HUANG RUI
QIN GUANGLI
ZHOU YE
Zhang kaiyang
XIONG ZHONGQING
CHEN SHUN
ZHENG WEIJIA

Assignees

宁波锦辉光学科技股份有限公司

Dates

Publication Date: 20260512
Application Date: 20260323

Claims (9)

1. The composite optical film with intrinsic hydrophobicity is characterized by comprising a substrate and an optical film system arranged on the substrate, wherein the optical film system at least comprises an organic-inorganic hybridization hydrophobic film layer; the organic-inorganic hybrid hydrophobic membrane layer comprises an inorganic porous framework and a plurality of organic chain segments dispersed in the inorganic porous framework; The organic segment has a reactive functional group crosslinked with the inorganic porous skeleton and a hydrophobic end group facing away from the inorganic porous skeleton, the reactive functional group being incorporated into the inorganic porous skeleton by a covalent bond; A plurality of the organic chain segments are aggregated in the inorganic porous framework to form an organic nano disperse phase; The inorganic porous skeleton has microscopic pores formed therein, the inorganic porous skeleton having microscopic porosity gradually increasing from an inner side surface close to the substrate to an outer side surface away from the substrate; In the thickness direction of the organic-inorganic hybrid hydrophobic membrane layer, the organic nano disperse phase is filled in microscopic pores of the inorganic porous framework in situ to form a space embedded structure with gradient increasing concentration distribution from the inner side surface to the outer side surface.
2. The composite optical film of claim 1, wherein the inorganic porous skeleton defines an opening that is a localized bottleneck of the microscopic pores and an internal cavity in communication with the opening, the opening having a pore size that is less than a maximum inner diameter of the internal cavity; The organic nanometer disperse phase filled in the micro-pore is internally entangled with the hydrophobic end groups of a plurality of organic chain segments in the internal cavity to form a molecular lock catch structure with the overall three-dimensional size larger than the aperture of the opening; The organic nano disperse phase is doubly anchored in the inorganic porous framework through covalent bonding of the reactive functional groups and physical limiting of the molecular lock catch structure.
3. The composite optical film of claim 1 wherein the organic segment further comprises a secondary crosslinkable group; Inside the same organic nano disperse phase, adjacent organic chain segments are mutually crosslinked through the secondary crosslinkable groups to form a flexible organic sub-network accommodated in the micro-pores; The flexible organic sub-network and the inorganic porous framework penetrate through each other in the organic-inorganic hybrid hydrophobic membrane layer to form a composite cross-linked framework.
4. The composite optical film according to claim 1, wherein the inorganic porous skeleton is a silica network; The organic chain segment is a fluorine-containing polymer chain segment with siloxane groups, and the siloxane groups are used as the reactive functional groups and are combined with the silicon dioxide network through silicon-oxygen-silicon covalent bonds.
5. The composite optical film according to claim 1, wherein the optical film system is an antireflection film system composed of high refractive index dielectric layers and low refractive index dielectric layers alternately laminated from the substrate in a direction away from the substrate; The organic-inorganic hybrid hydrophobic film layer is arranged on the outermost side of the antireflection film system far away from the substrate, and forms the outermost low refractive index medium layer of the antireflection film system.
6. The composite optical film according to claim 1, wherein the organic nanodispersed phase has a maximum three-dimensional size of 1 nm to 100 nm to suppress rayleigh scattering of visible light by the organic-inorganic hybrid hydrophobic film layer.
7. The composite optical film of claim 1, wherein the physical thickness of the organic-inorganic hybrid hydrophobic film layer is from 10 nm to 150 nm to provide mechanical abrasion resistance while retaining the visible light transmittance of the composite optical film.
8. The composite optical film according to claim 1, wherein the inorganic porous skeleton has an intrinsic refractive index greater than that of the organic segment; The gradient of the distribution concentration of the organic nanometer disperse phase from the inner side surface to the outer side surface increases gradually, so that the equivalent refractive index of the organic-inorganic hybrid hydrophobic film layer continuously decreases in the thickness direction of the organic-inorganic hybrid hydrophobic film layer.
9. A method of producing the composite optical film according to any one of claims 1 to 8, comprising the steps of: Providing the substrate and placing it in a vacuum deposition environment; Starting a first vapor deposition source to release a first deposition material forming the inorganic porous skeleton, and simultaneously starting a second vapor deposition source to release a second deposition material forming the organic chain segment, and performing codeposition on the substrate; dynamically modulating the deposition rate ratio of the first vapor deposition source to the second vapor deposition source in the co-deposition process to form a gradient distribution of the first deposition material and the second deposition material in a thickness direction away from the substrate; simultaneously, applying a pulsed ion beam with alternating energy field levels to the substrate during the co-deposition process; in the high-energy bombardment phase of the pulsed ion beam, high-energy ions drive the first deposition material to form the inorganic porous framework with the microscopic pores; and in the low-energy deposition phase of the pulsed ion beam, the second deposition material enters the microscopic pores in situ, and covalent bonding is carried out between the reactive functional group and the inorganic porous skeleton on the premise of retaining the activity of the hydrophobic end group, so that the organic nano disperse phase with gradually increased concentration gradient is formed by self-assembly.

Description

Composite optical film with intrinsic hydrophobicity and preparation method thereof Technical Field The invention relates to the technical field of optical films, in particular to a composite optical film with intrinsic hydrophobicity and a preparation method thereof. Background With rapid development of touch display, wearable equipment and vehicle-mounted optical systems, the composite optical film is required to have good hydrophobic and antifouling properties while providing optical properties such as anti-reflection and anti-reflection. Most of the existing hydrophobic antifouling treatments are to attach a fluorine-containing or silicon-containing organic low surface energy coating layer on the outer surface of an inorganic optical film through the processes of vapor deposition, spray coating or lifting. However, such applied surface coatings are generally thin and rely primarily on physical adsorption or limited interfacial chemical bonds to bond with the underlying film system, which are extremely prone to peeling and dissipation under prolonged ordinary wiping or external mechanical abrasion, resulting in rapid failure of the hydrophobic and anti-fouling function of the optical film. In order to improve abrasion resistance, attempts have been made in the industry to subject organic hydrophobic materials to conventional physical blending or continuous co-deposition with inorganic optical materials. However, the conventional co-deposition process is easy to cause irregular agglomeration of organic matters in an inorganic medium, which not only causes optical Rayleigh scattering to reduce the light transmittance of the film, but also greatly weakens the integral mechanical hardness of the film layer due to loose internal microstructure, and is difficult to consider the long-acting antifouling life and stable optical transmittance in a severe use environment. Disclosure of Invention Aiming at the technical defects that the hydrophobic antifouling coating on the surface of the optical film in the prior art is extremely easy to abrade and peel under mechanical friction to cause rapid failure of functions, and the conventional organic-inorganic co-deposition process is easy to cause loose internal structure of the film and poor overall mechanical strength, the invention provides a composite optical film with intrinsic hydrophobicity and a preparation method thereof. The composite optical film with intrinsic hydrophobicity provided by the invention comprises a substrate and an optical film system arranged on the substrate, wherein the optical film system at least comprises an organic-inorganic hybridization hydrophobic film layer; the organic-inorganic hybrid hydrophobic membrane layer comprises an inorganic porous framework and a plurality of organic chain segments dispersed in the inorganic porous framework; The organic segment has a reactive functional group crosslinked with the inorganic porous skeleton and a hydrophobic end group facing away from the inorganic porous skeleton, the reactive functional group being incorporated into the inorganic porous skeleton by a covalent bond; A plurality of the organic chain segments are aggregated in the inorganic porous framework to form an organic nano disperse phase; The inorganic porous skeleton has microscopic pores formed therein, the inorganic porous skeleton having microscopic porosity gradually increasing from an inner side surface close to the substrate to an outer side surface away from the substrate; In the thickness direction of the organic-inorganic hybrid hydrophobic membrane layer, the organic nano disperse phase is filled in microscopic pores of the inorganic porous framework in situ to form a space embedded structure with gradient increasing concentration distribution from the inner side surface to the outer side surface. Preferably, the inorganic porous skeleton defines an opening as a local bottleneck of the microscopic pores and an internal cavity communicating with the opening, and the pore diameter of the opening is smaller than the maximum inner diameter of the internal cavity; The organic nanometer disperse phase filled in the micro-pore is internally entangled with the hydrophobic end groups of a plurality of organic chain segments in the internal cavity to form a molecular lock catch structure with the overall three-dimensional size larger than the aperture of the opening; The organic nano disperse phase is doubly anchored in the inorganic porous framework through covalent bonding of the reactive functional groups and physical limiting of the molecular lock catch structure. Preferably, the organic segment further comprises a secondary crosslinkable group; Inside the same organic nano disperse phase, adjacent organic chain segments are mutually crosslinked through the secondary crosslinkable groups to form a flexible organic sub-network accommodated in the micro-pores; The flexible organic sub-network and the inorganic porous framework pe