CN114214021A

CN114214021A - Raw material composition for preparing optical adhesive, optical adhesive and optical adhesive film

Info

Publication number: CN114214021A
Application number: CN202210041156.9A
Authority: CN
Inventors: 刘楷楷; 樊燕; 董红星
Original assignee: NINGBO HUGHSTAR ADVANCED MATERIAL TECHNOLOGY CO LTD
Current assignee: NINGBO HUGHSTAR ADVANCED MATERIAL TECHNOLOGY CO LTD
Priority date: 2022-01-14
Filing date: 2022-01-14
Publication date: 2022-03-22
Anticipated expiration: 2042-01-14
Also published as: CN114214021B

Abstract

The application relates to the field of optical adhesive materials, in particular to a raw material composition for preparing optical adhesive, the optical adhesive and an optical adhesive film. The raw material composition for preparing the optical adhesive comprises the following components in parts by weight: 50-70 parts of polyacrylate oligomer, 10-30 parts of nano material, 10-40 parts of acrylate dimer and 3-5 parts of photoinitiator; the functionality of the polyacrylate oligomer is 1-6, and the number average molecular weight is 10000-; the raw material composition for preparing the optical adhesive has the advantages that the optical adhesive film prepared from the raw material composition is high in hardness and excellent in folding performance at normal temperature and low temperature.

Description

Raw material composition for preparing optical adhesive, optical adhesive and optical adhesive film

Technical Field

The application relates to the field of optical adhesive materials, in particular to a raw material composition for preparing optical adhesive, the optical adhesive and an optical adhesive film.

Background

With the rise of foldable display devices, the demand of foldable optical cement is increasingly strong, the optical cement plays a role in bonding structures of each layer in the foldable display devices, and meanwhile, stress generated in the folding process of each layer can be absorbed, and displacement and delamination of each laminated structure due to stress are prevented. Due to the requirement of absorption stress, the storage modulus of the foldable optical Adhesive (OCA) is very low, mostly 30-60kPa, and the OCA with low storage modulus has very soft hardness; for example, after the cover plate hardening film with 7H hardness is attached to the OCA with low storage modulus, the hardness of the combined laminated body is reduced to 3H, and the internal module of the foldable display device cannot be effectively protected.

Therefore, how to increase the hardness of the folded optical cement and make it have a higher storage modulus is a problem to be solved.

Disclosure of Invention

An object of the embodiments of the present application is to provide a raw material composition for preparing an optical adhesive, and an optical adhesive film, which aim to improve the hardness of a folded optical adhesive and make the folded optical adhesive have excellent folding performance when the folded optical adhesive is applied to adhering a folded display module and a cured film.

The application provides a raw material composition for preparing optical cement, which comprises the following components in parts by weight:

50-70 parts of polyacrylate oligomer, 10-30 parts of nano material, 10-40 parts of acrylate dimer and 3-5 parts of photoinitiator;

wherein the functionality of the polyacrylate oligomer is 1-6, and the number average molecular weight is 10000-200000;

the nano material is nano particles modified by at least one of acryloxysilane, epoxy silane and aminosilane; the shape of the nanoparticle before modification is ellipsoidal and/or rugby, and the particle size of the nanoparticle before modification is 5-500 nm.

The raw material composition for preparing the optical adhesive can be used for preparing the optical adhesive, and an optical adhesive film can be formed after the optical adhesive is formed into a film and cured; the nano material enables the storage modulus of the optical adhesive film to be different along different directions; because the stress and the steric hindrance of the ellipsoidal and rugby-shaped nanoparticles in different directions are different, the reaction groups used for modification by acryloyloxysilane, epoxysilane and aminosilane tend to be enriched along the upper and lower surfaces of the nanoparticles in the longitudinal axis direction (namely the z direction), and the reaction groups react with acrylate dimer and polyacrylate oligomer to form chemical bonds and are mainly distributed on the upper and lower surfaces in the longitudinal axis direction, so that the longitudinal axis direction has higher storage modulus, and the hardness of the optical adhesive film is improved; correspondingly, due to the fact that the chemical bond formed in the non-longitudinal axis direction is low in density and modulus, when the optical adhesive film is stressed in the width direction or the length direction, the nano particles can move, and therefore stress can be absorbed, and the folding performance of the optical adhesive film is not affected. Therefore, the raw material composition for preparing the optical adhesive provided by the application can be used for preparing the optical adhesive film with high hardness and folding performance.

In some embodiments herein, the polyacrylate oligomer comprises at least one of a polyester acrylate and a polyurethane acrylate.

In some embodiments of the present application, the polyacrylate oligomer comprises an aliphatic urethane acrylate;

optionally, the aliphatic urethane acrylate has a functionality of 1-3 and a number average molecular weight of 50000-100000.

In some embodiments of the present application, the nanomaterial is a nanoparticle modified with gamma-type acryloxysilane;

optionally, the gamma-type acryloxysilane includes gamma-acryloxypropyltrimethoxysilane, gamma-methacryloxypropyltrimethoxysilane, gamma-acryloxypropyltriethoxysilane; at least one of gamma-methacryloxypropyltriethoxysilane.

The gamma-type acryloyloxysilane modified nanoparticles are selected, the gamma-type acryloyloxysilane has an acryloyloxy bond, can perform a crosslinking reaction with acrylate resin in illumination, and has 3 carbon atoms on a main chain, so that not only is the close arrangement of silane in the z direction facilitated, but also certain elasticity of the silane in the x and y directions facilitated; the storage modulus in the z direction can be further increased, and the hardness can be improved.

In some embodiments of the present application, the nanoparticles comprise at least one of silica, alumina, zinc oxide, and magnesium oxide;

optionally, the nanoparticles have a particle size of 10-200 nm;

optionally, the nanoparticles have a particle size of 10-150 nm.

In some embodiments of the present application, the acrylate dimer comprises at least one of a methyl acrylate dimer, an ethyl acrylate dimer, and a methyl methacrylate dimer.

The application also provides an optical cement, and the optical cement is prepared from any one of the raw material compositions for preparing the optical cement.

In some embodiments of the present application, a method of preparing an optical cement includes:

mixing the nano material and the acrylate dimer at 20-30 ℃, then adding the polyacrylate oligomer for mixing, and then adding the photoinitiator for mixing.

The application provides an optical adhesive film, which is prepared by standing for more than 2 minutes and then curing after any one of the optical adhesives is formed into a film.

The application provides an optics glued membrane is higher at the storage modulus of thickness direction, has higher hardness. The optical adhesive film has a stress absorption effect in the non-thickness direction, and when the non-thickness direction is subjected to stretching or shrinking stress, the nano particles can move in the film, so that the optical adhesive film has good folding performance in the non-thickness direction.

In some embodiments of the present application, the optical adhesive film has a thickness of 50 to 125 μm;

optionally, the thickness of the optical adhesive film is 50-75 μm.

Drawings

In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings that are required to be used in the embodiments will be briefly described below, it should be understood that the following drawings only illustrate some embodiments of the present application and therefore should not be considered as limiting the scope, and for those skilled in the art, other related drawings can be obtained from the drawings without inventive effort.

Fig. 1 shows a schematic distribution diagram of the nano-materials in the optical adhesive film after the optical adhesive film is molded.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present application clearer, the technical solutions of the embodiments of the present application will be clearly and completely described below. The examples, in which specific conditions are not specified, were conducted under conventional conditions or conditions recommended by the manufacturer. The reagents or instruments used are not indicated by the manufacturer, and are all conventional products available commercially.

The following provides a raw material composition for preparing an optical adhesive, an optical adhesive and an optical adhesive film according to embodiments of the present disclosure.

Raw material composition for preparing optical cement

The raw material composition for preparing the optical cement comprises the following components in parts by weight:

50-70 parts of polyacrylate oligomer, 10-30 parts of nano material, 10-40 parts of acrylate dimer and 3-5 parts of photoinitiator. In other words, in the raw material composition for preparing the optical adhesive, the mass ratio of the polyacrylate oligomer, the nano material, the acrylate dimer and the photoinitiator is (50-70): (10-30): (10-40): (3-5).

In the application, the nano material is nano particles modified by at least one of acryloxysilane, epoxysilane and aminosilane; the shape of the nano particles before modification is ellipsoidal and/or rugby, and the particle size of the nano particles before modification is 5-500 nm.

In the present application, the particle size before nanoparticle modification is 5-500nm, and in some embodiments, the particle size before nanoparticle modification is 10-200 nm; in some embodiments, the nanoparticles have a particle size of 10-150 nm.

It should be noted that, in the embodiments of the present application, the nanoparticles may not have a single particle size, for example, the particle size of the nanoparticles may be within the foregoing range; for example, the nanoparticles may have a particle size of 5-100nm, 10-200nm, 12-500nm, 10-260nm, 10-110nm, 15-180nm, 12-300nm, and the like.

The shape of the nanoparticles before modification is ellipsoidal and/or rugby. In other words, the shape of the nanoparticle before modification is ellipsoidal; or the shape of the nanoparticles before modification is rugby shape; alternatively, the nanoparticles have both an ellipsoidal shape and an olivary shape before modification.

In some embodiments of the present application, nanoparticles modified with at least one of an acryloxysilane, an epoxysilane, and an aminosilane are commercially available; alternatively, the following examples may be used for modification: adding at least one of acryloxysilane, epoxy silane and aminosilane into ammonia water with the pH value of more than or equal to 12 or acetic acid water solution with the pH value of less than or equal to 3, preserving the temperature for a period of time at 50-60 ℃, then adding nanoparticles, and continuing to react for 1-2 h; and after the reaction is finished, replacing the modified nano material into an organic solvent or drying.

Fig. 1 shows a schematic diagram of a raw material composition for preparing an optical adhesive after forming an adhesive film, and for convenience of description, a thickness direction of the film is defined as a z direction, a width direction of the film is defined as an x direction, and a length direction of the film is defined as a y direction. Due to the characteristics of the structure of the ellipsoidal or rugby-shaped nano particles, the stress and the steric hindrance in different directions are different. After the nano particles are dispersed in a material containing polyacrylate oligomer and acrylate dimer, the nano particles are in a flat state under the action of gravity; after the surface of the nanoparticle is modified with the modifier (at least one of acryloxysilane, epoxysilane and aminosilane), the reactive groups in the modifier are easy to enrich on the upper surface and the lower surface of the particle in the z direction due to the steric hindrance of the nanoparticle, and are distributed less in the x direction and the y direction; in other words, the groups in the acryloxysilane, epoxysilane, and aminosilane are distributed predominantly at both ends of the particle in the z-direction; after the nano material is subjected to photocuring reaction with polyacrylate oligomer and acrylate dimer under the action of a photoinitiator, the nano material and the polyacrylate oligomer are crosslinked into bonds along two ends in the z direction, so that the high storage modulus in the z direction is obtained, and the hardness of the optical adhesive film is improved. Because the number of functional groups in the x direction and the y direction is small, and because of steric hindrance, the nano particles and the oligomer in the x direction and the y direction have few bonds, and the modulus is low; when the adhesive film is stressed in the x direction and the y direction, the adhesive film can move relatively, namely the adhesive film has a certain stress absorption effect and does not influence the folding performance.

In some embodiments of the present application, the nanoparticles comprise at least one of silica, alumina, zinc oxide, and magnesium oxide.

The nano particles are modified by at least one of acryloxysilane, epoxy silane and aminosilane to form the nano material.

For example, the aminosilane may be selected from at least one of gamma-aminopropyltriethoxysilane, gamma-aminopropyltrimethoxysilane, gamma-aminopropylmethyldimethoxysilane or gamma-aminopropylmethyldiethoxysilane.

For example, the acryloxysilane may be selected from at least one of acryloxytrimethylsilane, acryloxytriisopropylsilane, γ - (methacryloxy) propyltrimethoxysilane, γ - (methacryloxy) propylmethyldimethoxysilane.

For example, the epoxy silane may be one selected from the group consisting of 3- (2, 3-glycidoxy) propyltrimethoxysilane, 3- (2, 3-glycidoxy) propyltriethoxysilane, 3- (2, 3-glycidoxy) propylmethyldimethoxysilane, and 3- (2, 3-glycidoxy) propylmethyldiethoxysilane.

In some embodiments of the present application, the nanomaterial is a nanoparticle modified with gamma-acryloxysilane.

Alternatively, the gamma-type acryloxysilane includes gamma-acryloxypropyltrimethoxysilane, gamma-methacryloxypropyltrimethoxysilane, gamma-acryloxypropyltriethoxysilane; at least one of gamma-methacryloxypropyltriethoxysilane. The gamma-type acryloyloxysilane modified nano-particles are selected, so that the storage modulus in the z direction can be further increased, and the hardness is improved.

Illustratively, the polyacrylate oligomer may be present in an amount of 50 parts, 51 parts, 53 parts, 55 parts, 57 parts, 58 parts, 60 parts, 61 parts, 63 parts, 65 parts, 68 parts, 69 parts, 70 parts, etc., by weight of the base composition.

The functionality of the polyacrylate oligomer is 1-6, and the number average molecular weight is 10000-; for example, the functionality of the polyacrylate oligomer can be 1, 2, 3, 4, 5, 6, and the like; the number average molecular weight of the polyacrylate oligomer may be 10000, 20000, 30000, 50000, 70000, 80000, 100000, 140000, 150000, 160000, 180000, 200000, and the like.

The polyacrylate oligomer needs to be subjected to crosslinking reaction with groups modified on the surface of the nano particles, and needs to have a soft chain structure, and can be contracted and stretched when stressed, so that the polyacrylate oligomer absorbs the stress and has a foldable property; therefore, in the present application, the above polyacrylate oligomer is selected.

In some embodiments, the polyacrylate oligomer comprises at least one of a polyester acrylate and a polyurethane acrylate.

In some embodiments, the polyacrylate oligomer comprises an aliphatic urethane acrylate; the functionality of the aliphatic urethane acrylate is 1 to 3, and may be, for example, 1, 2, 3, etc., and the number average molecular weight of the aliphatic urethane acrylate is 50000, 60000, 70000, 80000, 90000, 100000, etc.

The aliphatic polyurethane acrylate has the advantages of high transparency, no yellowing, stable viscosity and the like, and can increase the transparency of the optical adhesive film.

As an example, the photoinitiator may be at least one selected from 1-hydroxycyclohexyl phenyl ketone, 1' - (methylenebis-4, 1-phenylene) bis [ 2-hydroxy-2-methyl-1-propanone ], 2-hydroxy-2-methyl-1-phenyl-1-propanone, 2-methyl-1- (4-methylthiophenyl) -2-morpholinyl-1-propanone, benzoin dimethyl ether and (2,4, 6-trimethylbenzoyl) diphenylphosphine oxide.

Optical cement

The optical cement provided by the application is prepared from any one of the raw material compositions for preparing the optical cement.

In some embodiments, the method of preparing an optical cement comprises: mixing the nano material and the acrylate dimer at the temperature of 20-30 ℃, then adding the polyacrylate oligomer for mixing, and then adding the photoinitiator for mixing.

In some embodiments, it is desirable to first modify the nanoparticles with at least one of an acryloxysilane, epoxysilane, and aminosilane. It is to be understood that in some embodiments, nanoparticles that have been modified with at least one of an acryloxysilane, epoxysilane, and aminosilane can be purchased directly for use.

For example, the nano material is added into the acrylate dimer and mixed uniformly, the mixing condition can be, for example, the rotation speed of a homogenizer is 2000-4000 r/min, stirring is carried out for 2h, and the temperature is kept between 20 and 25 ℃ during stirring; then adding polyacrylate oligomer, and continuing stirring for 0.5 h; the photoinitiator was added and stirring continued for 0.5 h. The whole charging process is carried out under a yellow lamp, and the charging is completed and then sealed in a dark place.

Optical adhesive film

The optical adhesive film is formed by forming any one of the optical adhesives and then curing.

As an example, the optical glue coating manner may be slit coating, comma coating, silk bar coating, or the like; staying for 2-5min in the horizontal direction after coating, and then curing, wherein in the curing process, the ultraviolet irradiation energy can be 400-1500Mj/cm²。

In the process of curing the optical adhesive coating film, due to steric hindrance and under the action of gravity, the arrangement mode of the nanoparticles in the film layer is almost the same as the schematic diagram in fig. 1; therefore, the storage modulus of the optical adhesive film in the z direction is higher, and the optical adhesive film has higher hardness. The optical adhesive film has a stress absorption function in the x direction and the y direction, and when the x direction and the y direction are stressed, the nano particles can move in the film, so that the optical adhesive film can be folded in the x direction and the y direction.

In some embodiments, the optical adhesive film is prepared to have a thickness of 50 to 125 μm, and illustratively, may have a thickness of 50 to 75 μm. For example, it may be 50 μm, 55 μm, 58 μm, 60 μm, 65 μm, 67 μm, 70 μm, 72 μm, 75 μm, 80 μm, 82 μm, 85 μm, 90 μm, 96 μm, 100 μm, 118 μm, 125 μm, or the like.

It should be noted that, in some other embodiments of the present application, the thickness of the optical adhesive film may be set according to a specific use scenario; in addition, the shape of the optical adhesive film can also be set according to a specific use scene, and the shape of the optical adhesive film is not limited in the application.

In some embodiments of the present application, the storage modulus of the optical adhesive film in the thickness direction is 80 to 150kPa, and the storage modulus in the direction perpendicular to the thickness is 30 to 50 kPa.

The optical adhesive film provided by the embodiment of the application has both the folding performance and the higher hardness.

The features and properties of the present application are described in further detail below with reference to examples.

In the following examples and comparative examples, the materials selected are illustrated as follows:

e274 (produced by Japanese catalyst) produced by Japanese catalyst is gamma-type methacryloxy trimethoxy silane modified ellipsoidal silica; the particle size of the ellipsoidal silicon dioxide is 80-120 nm.

UV265 from penno (r.v.) is gamma methacryloxytriethoxysilane modified oliveto-alumina; the particle size of the olive-type alumina is 20-30 nm.

The spherical silica E132 produced by the Japanese catalyst (produced by the Japanese catalyst) is spherical silica modified by gamma-methacryloxytrimethoxysilane; the particle size of the spherical silicon dioxide is 75-100 nm.

E-48 (produced by Japanese catalyst) produced by Japanese catalyst is gamma-type methacryloxy triethoxy silane modified ellipsoidal silica, and the particle size of the ellipsoidal silica is 200-250 nm.

Polyacrylate oligomer R385 (manufactured by Nippon synthetic chemistry) having a molecular weight of 80000 and a functionality of 1.

Polyacrylate oligomer PU5860 (from Dongguan) has a molecular weight of 3000 and a functionality of 9.

Examples 1 to 4, comparative examples 1 to 5

Examples 1-4, comparative examples 1-5 all provide a raw material composition for preparing an optical adhesive, and an optical adhesive film. The ingredients and proportions of the raw material composition for preparing the optical cement are shown in table 1.

The optical cement is prepared from the raw material composition shown in the table 1, and the specific preparation method is as follows:

slowly adding the nano material into the acrylate dimer, and stirring at a high speed of 4000 revolutions per minute at 2000 ℃ in a homogenizer for 2 hours at a temperature of 23 ℃; slowly adding polyacrylate oligomer, and continuously stirring for 0.5 h; the photoinitiator was then added and stirring was continued for 0.5 h. The whole charging process is carried out under a yellow lamp, and the optical cement is obtained by light-shielding and sealing after charging.

The optical adhesive film is formed by adopting the optical adhesive to form a film and then curing the film, and the preparation method comprises the following steps:

coating the optical adhesive coating on a release film to form a film with the thickness of 25-125 μm, and irradiating with ultraviolet light at the irradiation energy of 400-². And sticking a release film on the surface of the optical cement after curing.

The following tests were carried out on the products obtained in the respective examples and comparative examples.

The pencil hardness test method is as follows:

attaching a hardening film with the pencil hardness of 7H to an optical adhesive film to be tested, attaching the other surface of the optical adhesive film to be tested to glass with a flat and non-convex surface for testing, using an electric pencil hardness meter, a Mitsubishi pencil and a load of 750g, testing for 7H and 5 strips, testing for 6H if 3 or more than 3 strips are scratched, and recording the pencil hardness value of 6H if 3 or more than 3 strips are not scratched; if 3 or more scratches still exist, continuing to test for 5H; the 4H and 3H rules were tested as above.

On the contrary, in the 7H testing process, if 3 or more than 3 of 5 strips have no scratch, 8H is tested, and if 3 or more than 3 strips have scratch, the pencil hardness value is recorded as 7H; when the test is carried out for 8H, if 3 or more than 5 pencil leads are not scratched, the test is continued for 9H, and if 3 or more than 3 pencil leads are scratched, the pencil hardness value is recorded as 8H; whereas a pencil hardness value of 9H was recorded.

The normal temperature dynamic bending test method comprises the following steps:

the optical adhesive film to be tested is attached to the folding display module, the 7H hardening film is attached to the other side of the folding display module, then the hardening film is placed on a dynamic bending tester sample table towards the bending direction, the bending radius is set to be 1mm, after 1 ten thousand times of bending, a strong light flashlight is used for irradiating and observing whether a bending area is layered or not, if layering occurs, the test is stopped, the bending times are recorded, and if no anomaly exists, the test is continued.

And (3) testing the low-temperature dynamic bending by the following testing method:

attaching an optical adhesive film to be tested to a folding display module, attaching a 7H hardening film to the other side of the folding display module, then placing the hardening film on a sample table of a low-temperature dynamic bending tester facing the bending direction, setting the bending radius to be 1mm, setting the temperature to be-40 ℃, observing whether a layering field exists in a bending area or not by using strong light flashlight irradiation after bending for 1 thousand times, stopping the test if layering occurs, recording the bending times, and continuing the test if no anomaly exists.

Peel force test, test method as follows:

tearing off any release film of an optical adhesive film to be tested, attaching the optical adhesive film to the surface of 50 mu mPE, cutting the optical adhesive film into strips with the thickness of 25mm multiplied by 125mm, tearing off the other release film, attaching the optical adhesive film to the plain glass, pulling up one end of PET, testing 180-degree peel force by using a peel force testing machine, and recording test data.

The test results of examples 1 to 4 and comparative examples 1 to 5 are shown in table 1.

TABLE 1

Note: the normal-temperature dynamic bending and the low-temperature dynamic bending both adopt an inward bending form towards the surface of a hardening film, and the bending radius R is 1 mm.

From comparative example 1 and example 1 it can be seen that: in the preparation process of the optical cement, the temperature is not easy to be overhigh, the nano particles are agglomerated, and the bending performance is reduced.

From example 2 and comparative example 2 it can be seen that: the addition of the nano material can improve the hardness of the final optical adhesive film. Comparative example 2, in which no nanomaterial was added, had better low-temperature dynamic bending performance at-40 ℃, but had lower hardness.

From example 2 and comparative example 3 it can be seen that: compared with the spherical nano particles, the performance of dynamic bending at low temperature of minus 40 ℃ is obviously improved by adopting the ellipsoidal nano particles.

From example 2 and comparative example 4 it can be seen that: the nano material is less, and the hardness of the final optical adhesive film is lower.

From example 3 and comparative example 5 it can be seen that: the addition amount of the nano material is too much, and the normal-temperature dynamic bending performance and the low-temperature dynamic bending performance are reduced.

Examples 5 to 6, comparative examples 7 to 8

Examples 5-6, and comparative examples 7-8 all provide raw material compositions for preparing optical glues, and optical glue films. Referring to the preparation method and test means of example 1, the raw materials and test results of examples 5 to 6 and comparative examples 7 to 8 are shown in Table 2.

TABLE 2

From comparative example 6 and example 5 it can be seen that: the acrylate resin selected in example 5 is more advantageous in improving the peeling force and in stabilizing the bending property of the film. In comparative example 6, 9-functional resin with a smaller molecular weight was used, and the degree of photocuring crosslinking was too large, which resulted in a decrease in the adhesive strength of the optical adhesive film and further in a decrease in the folding property.

From comparative example 7 and example 5 it can be seen that: the bending performance is reduced due to the overlarge particle size of the nano material; the addition of 200-250nm ellipsoidal silica in comparative example 7 resulted in a decrease in bending properties and a slight decrease in hardness.

From comparative example 8 and example 5 it can be seen that: the bending performance is reduced due to excessive addition of the nano material; the addition of 35 parts by weight of oliveto-type alumina in comparative example 8 resulted in a decrease in bending properties.

The above description is only a preferred embodiment of the present application and is not intended to limit the present application, and various modifications and changes may be made by those skilled in the art. Any modification, equivalent replacement, improvement and the like made within the spirit and principle of the present application shall be included in the protection scope of the present application.

Claims

1. The raw material composition for preparing the optical cement is characterized by comprising the following components in parts by weight:

2. A feedstock composition for the preparation of an optical glue according to claim 1 wherein said polyacrylate oligomer comprises at least one of a polyester acrylate and a polyurethane acrylate.

3. A feedstock composition for the production of an optical glue according to claim 2 wherein said polyacrylate oligomer comprises an aliphatic urethane acrylate;

4. The raw material composition for preparing optical cement according to claim 1, wherein the nano material is a nano particle modified by gamma-type acryloxysilane;

optionally, the gamma-type acryloxysilane includes at least one of gamma-acryloxypropyltrimethoxysilane, gamma-methacryloxypropyltrimethoxysilane, gamma-acryloxypropyltriethoxysilane, and gamma-methacryloxypropyltriethoxysilane.

5. A raw material composition for optical cement as claimed in claim 1, wherein said nanoparticles comprise at least one of silica, alumina, zinc oxide and magnesium oxide;

optionally, the nanoparticles have a particle size of 10-200 nm;

optionally, the nanoparticles have a particle size of 10-150 nm.

6. A stock composition for use in making an optical glue as claimed in claim 1 wherein the acrylate ester dimer comprises at least one of methyl acrylate dimer, ethyl acrylate dimer and methyl methacrylate dimer.

7. An optical cement prepared from the raw material composition for optical cement according to any one of claims 1 to 6.

8. The optical glue of claim 7, wherein the preparation method of the optical glue comprises the following steps:

9. An optical adhesive film, wherein the optical adhesive film is prepared by standing for more than 2 minutes and then curing after the optical adhesive film of claim 7 or 8 is formed.

10. The optical adhesive film according to claim 9,

the thickness of the optical adhesive film is 50-125 μm;

optionally, the thickness of the optical adhesive film is 50-75 μm.