A display privacy film and preparation method thereof

Abstract

The present invention discloses a display privacy film, which comprises a first anti-Newton ring PET layer, a first transparent conductive layer, a privacy liquid crystal functional layer, a second transparent conductive layer, and a second anti-Newton ring PET layer, which are sequentially arranged from top to bottom, and the privacy liquid crystal functional layer comprises a black dye colloid wall and a liquid crystal colloid wall arranged at periodic intervals. The left and right viewing angles of the display privacy film are 40-50° at the narrowest viewing angle, and 140-160° at the widest viewing angle. The display viewing angle can be changed with an applied voltage, and has very good optical properties. The display privacy film preparation method adopts a two-time curing method for curing. After the first curing, the uncured black dye in the first curing is soaked out by a petroleum ether soaking method, and then the second curing is performed. This can not only avoid the adverse effects of the black dye on the optical properties of the privacy film, but also effectively improve the production yield of the privacy film and improve the production efficiency.

Description

Technical Field

[0001] The invention relates to a display anti-peep film, and in particular to a method for preparing the display anti-peep film. Background Art

[0002] In recent years, electronic products have developed rapidly, especially mobile terminals such as mobile phones have become necessities in people's daily lives, and people's personal privacy is stored in mobile phones more and more. The viewing angle of ordinary mobile phone screens is large, which can easily cause the leakage of people's personal privacy. For this reason, many people will stick anti-peep films on their mobile phones. The principle technology of anti-peep films adopts the principle of ultra-fine louvers. It is composed of multiple layers of materials. The anti-peep main body is a fine louver structure, which is realized by a parallel grating structure; the interval between the gratings is usually 0.02-0.1mm, and there will be PET protective film layers on the top and bottom. Through the angle control of light, the transmitted light is blocked by the grating and cannot pass through, forming a narrow viewing angle of the screen.

[0003] The shutter structure of the existing display anti-peep film is mainly composed of two parts: a liquid crystal colloid wall and a black dye colloid wall. In the prior art, during the curing process of the liquid crystal functional layer, the black dye colloid is difficult to be completely cured. The uncured black dye colloid material will have an adverse effect on the optical properties of the anti-peep film, and the product yield is low, resulting in an increase in the production cost of the anti-peep film. Therefore, it is necessary to further improve the existing feedback film and its preparation process. Summary of the invention

[0004] In order to overcome the above-mentioned deficiencies in the prior art, an object of the present invention is to provide a display privacy film with better optical performance.

[0005] To achieve the above-mentioned purpose and other related purposes, the technical solution provided by the present invention is: a display anti-peep film, which includes a first anti-Newton ring PET layer, a first transparent conductive layer, an anti-peep liquid crystal functional layer, a second transparent conductive layer, and a second anti-Newton ring PET layer arranged in sequence from top to bottom, the anti-peep liquid crystal functional layer includes a black dye colloid wall and a liquid crystal colloid wall arranged at periodic intervals, the width of the liquid crystal colloid wall is 30 to 100 um, the width of the black dye colloid wall is 20 to 50 um, the height of the liquid crystal colloid wall and the black dye colloid wall is 50 to 200 um, and the distance between the center lines of the liquid crystal colloid wall and the black dye colloid wall is 35 to 100 um.

[0006] Preferably, a microstructure layer is provided on the inner side surfaces of the first anti-Newton ring PET layer and the second anti-Newton ring PET layer relative to each other.

[0007] Preferably, the first transparent conductive layer and the second transparent conductive layer are indium tin oxide layers, nanosilver layers or graphene layers.

[0008] This patent also discloses a method for preparing a privacy film that can improve the optical performance of the display privacy film and effectively increase the product yield.

[0009] A preparation process of a display privacy film comprises the following steps:

[0010] 1) stirring the photopolymerizable monomer and the black dye, then adding the violet light initiator and the spacer ion and stirring, and then laminating the mixture between two layers of transparent ITO films through a laminating device to form a laminated film material;

[0011] 2) Cover the laminated film with a mask plate and perform the first UV curing to form a black dye colloid wall spaced between the two transparent ITO films;

[0012] 3) Soak the laminated film material that has undergone the first UV curing in petroleum ether to soak out all the uncured UV polymerizable monomers and black dye in the laminated film material;

[0013] 4) Mix the nematic liquid crystal and the photopolymerization monomer and stir, then add the ultraviolet light initiator and mix and stir, and then pour the mixed mixture into the laminating film material;

[0014] 5) The laminated film material is subjected to a second UV curing to form a liquid crystal colloid wall between the black dye colloid walls.

[0015] Preferably, the photopolymerizable monomer is one or a mixture of polyester acrylate, epoxy acrylate, unsaturated polyester, polyether acrylate, water-based acrylate and vinyl ether.

[0016] Preferably, the nematic liquid crystal is one or a mixture of SLC7011-100, E7, SLC1717 and SLC09535.

[0017] Preferably, the ultraviolet light initiator is one or more of Irgacure651, Irgacure2022, Irgacure2959, Irgacure127, and Irgacure184.

[0018] Preferably, the black dye colloid wall comprises, by mass percentage: 10-30% black dye, 65-85% photopolymerizable monomer, 0.1-3.5% ultraviolet light initiator, and 0.1-5% spacer.

[0019] Preferably, the liquid crystal colloid wall comprises, by mass percentage, 20-45% nematic liquid crystal, 50-75% photopolymerizable monomer, and 0.1-5% photoinitiator.

[0020] The above technical solution has the following beneficial effects: the left and right viewing angles of the display privacy film are 40-50° at the narrowest viewing angle, and 140-160° at the widest viewing angle. The display viewing angle can be changed with the applied voltage, and it has very good optical properties. The display privacy film preparation method adopts a two-time curing method for curing. After the first curing, the uncured black dye in the first curing is soaked out by petroleum ether soaking, and then the second curing is performed. This can not only avoid the adverse effects of the black dye on the optical properties of the privacy film, but also effectively improve the production yield of the privacy film and improve the production efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 It is a front view of an embodiment of the present invention.

[0022] Figure 2 It is a schematic structural diagram of the first solidification of an embodiment of the present invention.

[0023] Figure 3 Schematic diagram of the optical path in the non-powered state of an embodiment of the present invention.

[0024] Figure 4 Schematic diagram of the optical path in the power-on state of an embodiment of the present invention.

[0025] Component number description: 101, first anti-Newton ring PET layer; 102, first transparent conductive layer; 103, anti-peeping liquid crystal functional layer; 104, second transparent conductive layer; 105, second anti-Newton ring PET layer; 106, black dye colloid wall; 107, liquid crystal colloid wall. DETAILED DESCRIPTION

[0026] The following is a description of the implementation of the present invention by means of specific embodiments. Those skilled in the art can easily understand other advantages and effects of the present invention from the contents disclosed in this specification.

[0027] See also Figures 1 to 4 . It should be noted that the structures, proportions, sizes, etc. illustrated in the drawings in this specification are only used to match the contents disclosed in the specification for people familiar with this technology to understand and read, and are not used to limit the limiting conditions for the implementation of the present invention, so they have no substantial technical significance. Any modification of the structure, change in the proportional relationship, or adjustment of the size should still fall within the scope of the technical content disclosed by the present invention without affecting the effects and purposes that can be achieved by the present invention. At the same time, the terms such as "upper", "lower", "left", "right", "middle" and "one" quoted in this specification are only for the convenience of description, and are not used to limit the scope of the implementation of the present invention. Changes or adjustments in their relative relationships should also be regarded as the scope of the implementation of the present invention without substantially changing the technical content.

[0028] like Figure 1 As shown, this patent discloses a display privacy film, which includes a first anti-Newton ring PET layer 101, a first transparent conductive layer 102, a privacy liquid crystal functional layer 103, a second transparent conductive layer 104, and a second anti-Newton ring PET layer 105 arranged in sequence from top to bottom. The first anti-Newton ring PET layer 101 and the second anti-Newton ring PET layer 105 are arranged on both sides of the entire film body, which can better protect the film body. In order to prevent the problem of mutual adsorption of film materials, a microstructure layer can be arranged on the inner side surfaces opposite to the first anti-Newton ring PET layer 101 and the second anti-Newton ring PET layer 105.

[0029] The first transparent conductive layer 102 and the second transparent conductive layer 104 are used to energize the anti-peeping liquid crystal functional layer 103. The first transparent conductive layer 102 and the second transparent conductive layer 104 are indium tin oxide layers, nanosilver layers or graphene layers. When the electric field is turned off, the liquid crystal in the anti-peeping liquid crystal functional layer is in a light scattering state, and the transmitted light is distributed in a wide angle range (such as Figure 3 As shown); when the electric field is turned on, the liquid crystal in the anti-peeping liquid crystal functional layer is transparent, and after the incident light passes through the periodic light shielding stripe structure, the transmitted light is distributed in a narrow angle range (as shown Figure 4 as shown).

[0030] The anti-peeping liquid crystal functional layer 103 includes a black dye colloid wall 106 and a liquid crystal colloid wall 107 arranged at periodic intervals. The width of the liquid crystal colloid wall 107 is 30 to 100 um, the width of the black dye colloid wall 106 is 20 to 50 um, the height of the liquid crystal colloid wall 107 and the black dye colloid wall 106 is 50 to 200 um, and the distance between the center lines of the liquid crystal colloid wall 107 and the black dye colloid wall 106 is 35 to 100 um. This setting can effectively improve the optical properties of the entire anti-peeping film and make its viewing angle in the best state. The anti-peeping film with this structure has a left-right viewing angle of 40-50° at the narrowest viewing angle and a left-right viewing angle of 140-160° at the widest viewing angle, and can be adjusted with the voltage. The display anti-peeping film of the present invention has the characteristic of adjustable transmission light angle range. This display anti-peep film is expected to be applied to displays. By turning the electric field on and off, the display can be switched between different viewing angles, that is, switched between anti-peep and non-anti-peep states. It can be applied to optical display fields such as computers, smart phones, and ATM displays.

[0031] The present invention also discloses a method for preparing an anti-peep film, and a specific embodiment thereof is as follows:

[0032] Embodiment 1

[0033] 1) Stirring a photopolymerizable monomer and a black dye, then adding a violet light initiator and spacer ions and stirring, and then laminating the mixture between two layers of transparent ITO films through a laminating device to form a laminated film material, forming a thin layer of 50 to 200 microns thick; the photopolymerizable monomer adopts a mixture of polyester acrylate: polyolefin acrylate: polyether acrylate in a mass ratio of 2:4:2, the photopolymerizable monomer accounts for 80% of the total mass, and the black dye accounts for 18% of the total mass. After the black dye and the photopolymerizable monomer are mixed and stirred for 50 minutes, an ultraviolet light initiator Irgacure184 and 50um glass microbeads are added, and the ultraviolet light initiator Irgacure184 and the 50um glass microbeads account for 1% of the total mass respectively. After stirring for 30 minutes, the mixture is laminated between two layers of transparent ITO films through a laminating device;

[0034] 2) If Figure 2 As shown, a mask plate is covered on the laminated film at 25°C, and the first UV curing is performed to form a black dye colloid wall set between the two transparent ITO films; the light intensity used for the first UV curing is 5mw / cm 2 The UV irradiation was completed for 6 min.

[0035] 3) Soak the laminated film material that has undergone the first UV curing in petroleum ether for a period of time to soak out all the uncured UV polymerizable monomers and black dyes in the laminated film material;

[0036] 4) Mix the nematic liquid crystal and photopolymerization monomer and stir, then add the ultraviolet initiator to mix and stir, and then pour the mixture into the laminated film; select positive nematic liquid crystal, the mass ratio of which is SLC7011-100: E7: SLC09535 = 2:1:1, and the positive nematic liquid crystal accounts for 45% of the total mass; the photopolymerization monomer uses a mass ratio of polyester acrylate: polyolefin acrylate: polyether acrylate = 2:4:2 mixture, and the photopolymerization monomer accounts for 54% of the total mass. After mixing the positive nematic liquid crystal and the photopolymerization monomer and stirring for 50 minutes, add the ultraviolet initiator Irgacure184, which accounts for 1% of the total mass, and stir for 30 minutes before pouring into the film under negative pressure.

[0037] 5) Perform a second UV curing on the laminated film to form a liquid crystal colloid wall between the black dye colloid walls. The second UV curing uses a light intensity of 5mw / cm 2 UV irradiation for 10 min.

[0038] Embodiment 2

[0039] 1) Stirring a photopolymerizable monomer and a black dye, then adding a violet light initiator and spacer ions and stirring, and then laminating the mixture between two layers of transparent ITO films through a laminating device to form a laminated film material; the mass ratio of the photopolymerizable monomer is polyester acrylate, the photopolymerizable monomer accounts for 85% of the total mass, and the black dye accounts for 10% of the total mass. After the black dye and the photopolymerizable monomer are mixed and stirred for 50 minutes, an ultraviolet light initiator Irgacure2022 and 50um glass microbeads are added, the ultraviolet light initiator Irgacure2022 accounts for 3.5% of the total mass, and the 50um glass microbeads account for 1.5% of the total mass. After stirring for 30 minutes, the mixture is laminated between two layers of transparent ITO films through a laminating device;

[0040] 2) If Figure 2 As shown, a mask plate is covered on the laminated film material, and the first UV curing is performed to form a black dye colloid wall set between the two transparent ITO films; the light intensity used for the first UV curing is 5mw / cm 2 The UV irradiation was completed for 6 min.

[0041] 3) Soak the laminated film material that has undergone the first UV curing in petroleum ether for a period of time to soak out all the uncured UV polymerizable monomers and black dyes in the laminated film material;

[0042] 4) Mix the nematic liquid crystal and photopolymerization monomer and stir, then add the ultraviolet initiator and mix and stir, and then pour the mixture into the laminated film; select positive nematic liquid crystal, the mass ratio of which is SLC7011-100: SLC09535 = 1:1, and the positive nematic liquid crystal accounts for 20% of the total mass; the photopolymerization monomer uses polyether acrylate, and the photopolymerization monomer accounts for 75% of the total mass. After mixing the positive nematic liquid crystal and the photopolymerization monomer and stirring for 50 minutes, add the ultraviolet initiator Irgacure184, which accounts for 5% of the total mass, and stir for 30 minutes before pouring into the film under negative pressure.

[0043] 5) Perform a second UV curing on the laminated film to form a liquid crystal colloid wall between the black dye colloid walls. The second UV curing uses a light intensity of 5mw / cm 2 UV irradiation for 10 min.

[0044] Embodiment 3

[0045] 1) Stirring a photopolymerizable monomer and a black dye, then adding a violet light initiator and spacer ions and stirring, and then laminating the mixture between two layers of transparent ITO films through a laminating device to form a laminated film material; the mass ratio of the photopolymerizable monomer is polyester acrylate, the photopolymerizable monomer accounts for 65% of the total mass, and the black dye accounts for 28% of the total mass. After the black dye and the photopolymerizable monomer are mixed and stirred for 50 minutes, an ultraviolet light initiator Irgacure2022 and 50um glass microbeads are added, the ultraviolet light initiator Irgacure2022 accounts for 3.5% of the total mass, and the 50um glass microbeads account for 3.5% of the total mass. After stirring for 30 minutes, the mixture is laminated between two layers of transparent ITO films through a laminating device;

[0046] 2) If Figure 2 As shown, a mask plate is covered on the laminated film material, and the first UV curing is performed to form a black dye colloid wall set between the two transparent ITO films; the light intensity used for the first UV curing is 5mw / cm 2 The UV irradiation was completed for 6 min.

[0047] 3) Soak the laminated film material that has undergone the first UV curing in petroleum ether for a period of time to soak out all the uncured UV polymerizable monomers and black dyes in the laminated film material;

[0048] 4) Mix the nematic liquid crystal and the photopolymerization monomer and stir them, then add the ultraviolet initiator and stir them, and then pour the mixture into the laminated film material; select positive nematic liquid crystal, SLC7011-100 is used for the positive nematic liquid crystal, and the positive nematic liquid crystal accounts for 30% of the total mass; the photopolymerization monomer uses polyether acrylate, and the photopolymerization monomer accounts for 69.9% of the total mass. After the positive nematic liquid crystal and the photopolymerization monomer are mixed and stirred for 50 minutes, the ultraviolet initiator Irgacure184 is added, and the ultraviolet initiator Irgacure651 accounts for 0.1% of the total mass. After stirring for 30 minutes, pour it into the film under negative pressure conditions;

[0049] 5) Perform a second UV curing on the laminated film to form a liquid crystal colloid wall between the black dye colloid walls. The second UV curing uses a light intensity of 5mw / cm 2 UV irradiation for 10 min.

[0050] Embodiment 4

[0051] 1) Stirring a photopolymerizable monomer and a black dye, then adding a violet light initiator and spacer ions and stirring, and then laminating the mixture between two layers of transparent ITO films through a laminating device to form a laminated film material; the mass ratio of the photopolymerizable monomer is polyester acrylate, the photopolymerizable monomer accounts for 69.8% of the total mass, and the black dye accounts for 30% of the total mass. After the black dye and the photopolymerizable monomer are mixed and stirred for 50 minutes, an ultraviolet light initiator Irgacure2022 and 50um glass microbeads are added, the ultraviolet light initiator Irgacure2022 accounts for 0.1% of the total mass, and the 50um glass microbeads account for 0.1% of the total mass. After stirring for 30 minutes, the mixture is laminated between two layers of transparent ITO films through a laminating device;

[0052] 2) If Figure 2 As shown, a mask plate is covered on the laminated film material, and the first UV curing is performed to form a black dye colloid wall set between the two transparent ITO films; the light intensity used for the first UV curing is 5mw / cm 2 The UV irradiation was completed for 6 min.

[0053] 3) Soak the laminated film material that has undergone the first UV curing in petroleum ether for a period of time to soak out all the uncured UV polymerizable monomers and black dyes in the laminated film material;

[0054] 4) Mix the nematic liquid crystal and the photopolymerization monomer and stir them, then add the ultraviolet initiator and stir them, and then pour the mixture into the laminated film material; select positive nematic liquid crystal, SLC7011-100 is used for the positive nematic liquid crystal, and the positive nematic liquid crystal accounts for 45% of the total mass; the photopolymerization monomer uses polyether acrylate, and the photopolymerization monomer accounts for 50% of the total mass. After the positive nematic liquid crystal and the photopolymerization monomer are mixed and stirred for 50 minutes, the ultraviolet initiator Irgacure184 is added, and the ultraviolet initiator Irgacure651 accounts for 5% of the total mass. After stirring for 30 minutes, pour it into the film under negative pressure conditions;

[0055] 5) Perform a second UV curing on the laminated film to form a liquid crystal colloid wall between the black dye colloid walls. The second UV curing uses a light intensity of 5mw / cm 2 UV irradiation for 10 min.

[0056] The display privacy film has a left and right observation angle of 40-50° at the narrowest viewing angle and a left and right observation angle of 140-160° at the widest viewing angle. The display viewing angle can be changed with the applied voltage, and has very good optical properties. The display privacy film preparation method adopts a two-time curing method for curing. After the first curing, the uncured black dye in the first curing is soaked out by petroleum ether soaking, and then the second curing is performed. This not only avoids the adverse effects of the black dye on the optical properties of the privacy film, but also effectively improves the production yield of the privacy film and improves the production efficiency. Therefore, the present invention effectively overcomes the various shortcomings of the prior art and has a high industrial utilization value.

[0057] The above embodiments are merely illustrative of the principles and effects of the present invention, and are not intended to limit the present invention. Anyone familiar with the art may modify or alter the above embodiments without departing from the spirit and scope of the present invention. Therefore, all equivalent modifications or alterations made by a person of ordinary skill in the art without departing from the spirit and technical concept disclosed by the present invention shall still be covered by the claims of the present invention.

Claims

1. A display privacy film, characterized in that: It includes a first anti-Newton ring PET layer, a first transparent conductive layer, an anti-peeping liquid crystal functional layer, a second transparent conductive layer, and a second anti-Newton ring PET layer which are arranged in sequence from top to bottom. The anti-peeping liquid crystal functional layer includes a black dye colloid wall and a liquid crystal colloid wall which are arranged at periodic intervals. The width of the liquid crystal colloid wall is 30 to 100 um, the width of the black dye colloid wall is 20 to 50 um, the height of the liquid crystal colloid wall and the black dye colloid wall is 50 to 200 um, the distance between the center lines of the liquid crystal colloid wall and the black dye colloid wall is 35 to 100 um, and the liquid crystal colloid wall includes, by mass percentage, 20 to 45% of nematic phase liquid crystal, 50 to 75% of photopolymerizable monomer, and 0.1 to 5% of photoinitiator.

2. The display privacy film according to claim 1, characterized in that: Microstructure layers are arranged on the inner sides of the first anti-Newton ring PET layer and the second anti-Newton ring PET layer that are opposite to each other.

3. The display privacy film according to claim 1, characterized in that: The first transparent conductive layer and the second transparent conductive layer are indium tin oxide layers, nano silver layers or graphene layers.

4. A process for preparing a display privacy film, characterized in that: It includes the following steps: 1) stirring the photopolymerizable monomer and the black dye, then adding the violet light initiator and the spacer ion and stirring, and then laminating the mixture between two layers of transparent ITO films through a laminating device to form a laminated film material; 2) Cover the laminated film with a mask plate and perform the first UV curing to form a black dye colloid wall spaced between the two transparent ITO films; 3) Soak the laminated film material that has undergone the first UV curing in petroleum ether to soak out all the uncured UV polymerizable monomers and black dye in the laminated film material; 4) Mix the nematic liquid crystal and the photopolymerization monomer and stir, then add the ultraviolet light initiator and mix and stir, and then pour the mixed mixture into the laminating film material; 5) The laminated film material is subjected to a second UV curing to form a liquid crystal colloid wall between the black dye colloid walls.

5. The process for preparing the display privacy film according to claim 4, characterized in that: The photopolymerizable monomer is one or a mixture of polyester acrylate, epoxy acrylate, unsaturated polyester, polyether acrylate, water-based acrylate and vinyl ether.

6. The process for preparing the display privacy film according to claim 4, characterized in that: The nematic liquid crystal is one or a mixture of SLC7011-100, E7, SLC1717 and SLC09535.

7. The process for preparing the display privacy film according to claim 4, characterized in that: The ultraviolet light initiator is one or more of Irgacure651, Irgacure2022, Irgacure2959, Irgacure127 and Irgacure184.

8. The process for preparing the display privacy film according to claim 4, characterized in that: The black dye is black ink.

9. The process for preparing the display privacy film according to claim 4, characterized in that: The black dye colloid wall comprises, by mass percentage, 10-30% of black dye, 65-85% of photopolymerizable monomer, 0.1-3.5% of ultraviolet light initiator and 0.1-5% of spacer.

10. The process for preparing the display privacy film according to claim 4, characterized in that: The liquid crystal colloid wall includes, by mass percentage, 20-45% of nematic liquid crystal, 50-75% of photopolymerizable monomer, and 0.1-5% of photoinitiator.

Images