KR102132698B1 - Shatterproof film and method for manufacturing the same - Google Patents

Abstract

The anti-scattering film of the present invention includes an adhesive layer; A transparent film layer on the adhesive layer; And a hard coating layer on the transparent film layer. It includes, it is characterized in that the hard coating layer is capable of double curing. The scattering prevention film of the present invention, preparing a heart coating layer resin composition containing 50 to 100 parts by weight of an urethane acrylate oligomer, 0.1 to 3 parts by weight of a photoinitiator, and 0.1 to 3 parts by weight of a thermal initiator relative to 100 parts by weight of an acrylate resin ; After applying the resin composition on the optical transparent film, heat curing to form a hard coating layer; Coating the adhesive composition on the surface of the optical transparent film to which the resin composition is not applied; And after applying a molding resin on the hard coating layer, irradiating light; It includes.
The scattering prevention film of the present invention is characterized in that the adhesion between the hard coating layer and the molding resin layer is dramatically increased by double curing of heat curing and photo curing.

Description

Shatterproof film and method for manufacturing the same}

The present invention relates to an anti-scattering film and a method for manufacturing the anti-scattering film.

The structure of a touch screen panel applied to a mobile phone, etc. is in a trend to switch from a conventional multi-layer structure to an integrated structure. The structure of the integrated touch screen panel is due to the fact that a transparent electrode (ITO) film having a high cost specific gravity is not required.

Through the integrated touch screen panel structure, it is possible to slim the product and increase the visible light transmittance. Despite the above advantages, there is a frequent problem that the cover glass on the display surface is broken by a drop impact or the like.

Accordingly, in order to enhance stability against debris generated when the glass of the portable device is broken, a scattering prevention film is inserted between the panel and the cover glass to prevent scattering of the cover glass.

Such a scattering prevention film generally includes a structure of a hard coating layer/substrate/adhesive layer, and due to its characteristics, surface hardness and optical characteristics are required for the hard coating layer. However, since the hard coating layer is provided with scratch resistance, the surface tension is low, and thus the bonding strength with the resin molding layer on the upper part is low, and thus it is difficult to secure reliability under a hot water condition or a high temperature and high humidity environment.

Korean Patent Publication No. 2013-0071582 attempted to solve the above problem by lowering the pencil hardness of the hard coating layer and consequently lowering the surface tension of the hard coating layer. However, the scattering prevention film has a problem such as occurrence of a pressing problem due to the polyethylene protective film used to protect the hard coating layer and the scratch resistance is poor due to the low pencil hardness.

Accordingly, there is a need to develop a scattering prevention film that secures reliability by increasing the bonding force between the hard coating layer and the molding resin layer.

Korean Open Patent No. 10-2013-0071582

The present invention has been made to solve the above problems and is intended to provide an increase in adhesion between the hard coating layer and the molding resin layer constituting the shatterproof film.

However, the technical problem to be achieved in the present invention is not limited to the above-mentioned problems, and other problems that are not mentioned will be clearly understood by those skilled in the art from the following description.

The scattering prevention film of the present invention includes an adhesive layer; A transparent film layer on the adhesive layer; And a hard coating layer on the transparent film layer. It includes, it is characterized in that the hard coating layer is capable of double curing.

The transparent film may include one or two or more selected from the group consisting of polyethylene terephthalate, polyether sulfone, and thermoplastic polyurethane.

The hard coating layer is characterized in that the pencil hardness is B or more and is cured simultaneously when the UV mold is cured.

The thickness of the hard coating layer may be 1㎛ ~ 3㎛.

A molding resin layer may be further formed on the hard coating layer.

The production method of the shatterproof film of the present invention, a heart coating layer resin composition comprising 50 to 100 parts by weight of an urethane acrylate oligomer, 0.1 to 3 parts by weight of a photoinitiator, and 0.1 to 3 parts by weight of a thermal initiator relative to 100 parts by weight of an acrylate resin Preparing; After applying the resin composition on the optical transparent film, forming a hard coating layer by thermal curing; Coating the adhesive composition on the surface of the optical transparent film to which the resin composition is not applied; And after applying a molding resin on the hard coating layer, irradiating light; It includes.

The scattering prevention film of the present invention, through the introduction of a double curing method of thermal curing and photocuring, the initial hard coating layer formation, the thermal curing method, and then, through the photocuring, the bonding strength between the hard coating layer and the molding resin layer jumped It works.

1 is a cross-sectional view of a shatterproof film according to an embodiment of the present invention.
2 is a cross-sectional view of an anti-scattering film according to another embodiment of the present invention.

Hereinafter, exemplary embodiments of the present invention will be described in detail with reference to the accompanying drawings so that those skilled in the art to which the present invention pertains can easily practice. The present invention can be implemented in many different forms and is not limited to the embodiments described herein.

In the following, if the “top (or bottom)” of the substrate is provided with an arbitrary configuration, not only does it mean that an arbitrary configuration is formed in contact with the upper surface (or lower surface) of the substrate, but also on the substrate and the substrate (or It is not limited to not including other components between any components formed.

The anti-scattering film of the present invention includes an adhesive layer; A transparent film layer on the adhesive layer; And a hard coating layer on the transparent film layer. It includes, it is characterized in that the hard coating layer is capable of double curing.

The hard coating layer of the scattering prevention film of the present invention adopts both a thermal curing method and a photo curing method, and the formation of an initial hard coating layer introduces a thermal curing method, and then to the hard coating layer of the scattering prevention film for UV (UV) molding When the molding resin is applied, and the photocuring initiator of the heat-cured hard coating layer simultaneously reacts, the bonding force between the hard coating layer and the UV molding increases dramatically due to the chemical photocuring reaction between the UV mold and the hard coating layer. will be.

1 is a view schematically showing an anti-scattering film according to an embodiment of the present invention. Referring to FIG. 1, a hard coating layer 103, a transparent film layer 102, and an adhesive layer 101 formed from above may be included, and a release film may be further included under the adhesive layer.

2 is a view schematically showing an anti-scattering film according to another embodiment of the present invention. Referring to FIG. 2, a molding resin layer 104 may be further formed on the hard coating layer 103.

Hereinafter, the hard coating layer of the present invention will be described in detail.

The thickness of the hard coating layer can be appropriately selected according to the specific use of the anti-scattering film. For example, the thickness of the hard coating layer may be 0.5 μm to 15 μm, more preferably 1 μm to 8 μm, and most preferably 1 μm to 3 μm. The hard coating layer may have a sufficient surface hardness when the thickness is within the above range, thereby preventing the phenomenon that the hard coating layer is damaged or the scratch resistance is deteriorated, and also reduces cracking due to stress such as bending, thereby improving bending resistance. It is possible to prevent the problem from being reduced. The material of the hard coating layer is not particularly limited, and may be selected to have an appropriate hardness according to a specific application.

The heart coating layer of the present invention is characterized by being formed of a composition comprising an acrylate resin, a urethane acrylate oligomer, a photoinitiator and a thermal initiator.

The acrylate resin includes at least two or more, preferably 2 to 15 functional groups, and contributes to improving hardness and preventing wrinkles. At this time, if the number of functional groups included in the ultraviolet-curable acrylate resin is less than 2, the addition effect may be insufficient, whereas, when the number of functional groups exceeds 15, wrinkles may occur.

The urethane acrylate oligomer may be one selected from the group consisting of tetramethylene diisocyanate, hexamethylene diisocyanate, and combinations thereof.

The weight average molecular weight of the urethane acrylate oligomer may be 500 to 10,000 or less. When the weight average molecular weight is less than 500, scratch resistance and the like are excellent, but since curing shrinkage is increased, curl phenomenon of the optical film cannot be suppressed. If the curl phenomenon is severe, it is difficult to use it as a hard coating film. When a urethane acrylate oligomer having a weight average molecular weight of more than 10,000 is used, the cured resin layer becomes soft and the hard coating function of the optical film is deteriorated, and scratch resistance and film strength are not excellent.

It is preferable that the urethane acrylate oligomer is 50 to 100 parts by weight based on 100 parts by weight of the acrylate resin. If it is outside the above range, there is a problem that the adhesion between the hard coating layer and the molding resin layer is not good.

The thermal initiator is a material capable of generating radicals by heat, and an NCO-based curing agent or an epoxy-based curing agent may be selected.

The thermal initiator is preferably included in an amount of 0.001 to 3% by weight in the mixture for thermal initiation polymerization. If the content of the initiator is less than the above range, the amount is insufficient and the yield of converting the monomer into polymer particles may decrease and the polymerization time may be long. On the contrary, when the content exceeds the above range, the polymerization time is shortened, but the average molecular weight of the resulting polymer is low. The molecular weight distribution may be wide.

The photoinitiator can be used without limitation as long as it forms a radical in response to light so that the photopolymerizable monomer can perform a polymerization reaction. As an example, 2,2-diethoxy acetophenone, 3-methyl acetophenone, α-dimethoxy-α-hydroxy acetophenone, 4,4′-dimethoxy benzophenone, 1-hydroxy-cyclohexyl-phenylketone And combinations of these, one type selected from the group.

The photoinitiator may be included in the range of 0.001 to 5% by weight of the mixture for the photoinitiation polymerization reaction. If the content of the photoinitiator is too small, there is a fear that sufficient polymerization may not proceed, and when the content is too large, there may be a possibility of deteriorating physical properties due to the presence of unreacted products after curing.

The hard coating composition may further add additives as long as it can maintain hard coating properties for use as a hard coating layer in the anti-scattering film, for example, dyes, fillers (fillers), reinforcing agents, flame retardants, Plasticizers, lubricants, stabilizers (antioxidants, UV absorbers, heat stabilizers, etc.), mold release agents, antistatic agents, surfactants, dispersants, flow control agents, leveling agents, antifoaming agents, surface modifiers, low stress agents (silicone oil ), silicone rubber, various plastic powders, etc.), and heat resistant improvers.

The hard coating layer of the present invention composed of the above composition has a pencil hardness of B or more, and is characterized in that the UV cures at the same time when the mold is cured.

The transparent film has excellent strength so as to prevent scattering of glass, such as tempered glass of a touch screen panel, and transmittance of at least 90% or more, preferably 90 to 100, so as not to impair optical properties. % May be a film having excellent transparency.

As such a transparent film, polyethylene terephthalate (polyethylene terephthalate; PET), polyethylene naphthalate (PEN), polyethersulfone (PES), polycarbonate (Poly carbonate; PC), polyethylene (polyethylene; PE), It is preferable to use one or more selected from the group consisting of poly propylene (PP), thermoplastic polyurethane (TPU) or combinations thereof, more preferably polyethylene terephthalate, polyether sulfone and thermoplastic It is preferable to include one or two or more selected from the group consisting of polyurethane, and it is preferable to use an optical PET film having a visible light transmittance of 92%.

The adhesive layer 130 is formed under the base layer 110, and the adhesive layer 130 may be formed for attachment to a touch screen panel, which is an adhered surface. The pressure-sensitive adhesive layer 130 can be used without limitation, known pressure-sensitive adhesives such as acrylic pressure-sensitive adhesives, silicone pressure-sensitive adhesives, acid-free type hydroxyl-containing pressure-sensitive adhesives. The adhesive layer 130 may include one or more selected from among them. For example, an acid-free hydroxyl-containing adhesive may include known photoinitiators such as 2-ethylhexyl acrylate, hydroxyethyl acrylate, and benzophenone, and may contain additives. It may further include. The additive is for improving the physical properties of the pressure-sensitive adhesive, and known curing accelerators, plasticizers, dispersants, surfactants, antistatic agents, antifoaming agents, leveling agents, and the like can be used without limitation.

Referring to FIG. 2, according to an embodiment of the present invention, a molding resin layer 104 may be formed on the hard coating layer 103. The molding resin layer 104 is formed to implement a design on a shatterproof film. The molding resin layer 104 may be preferably made of acrylic resin or polycarbonate, but is not limited thereto. In addition, the molding resin layer 104 may be cured by ultraviolet light. Ink or the like may be deposited on the molding resin layer 104 for decoration.

Hereinafter, the configuration and operation of the present invention will be described in more detail through preferred embodiments of the present invention. However, this is presented as a preferred example of the present invention, and in no sense can be interpreted as limiting the present invention.

Example 1

With respect to 100 parts by weight of acrylate resin (60 parts by weight of methyl methacrylate units, 30 parts by weight of butyl methacrylate units, and acrylate resin polymerized in a ratio of 10 parts by weight of glycidyl methacrylate units) Urethane acrylate oligomer (6 or more functional, molecular weight 600 to 1200, brand name: Miwon MU9800) 100 parts by weight, photoinitiator (Irgacure 184) 0.3 parts by weight, thermal initiator (NA-30 as an epoxy watch curing agent, Cosmotech) 1.0 parts by weight , Additives (A187, Evonik) 0.1 µm by weight of 1 part by weight of a hard coating agent on optical PET, heat-cured, and then coated with a pressure-sensitive adhesive on the back of PET to produce a shatterproof tape. After coating the UV mold on the hard coating surface, it was cured with UV.

Example 2

In Example 1, in the composition of the hard coating layer, in the same manner as in Example 1, except that the urethane acrylate oligomer was changed to 50 parts by weight with respect to 100 parts by weight of the acrylate resin, a scattering prevention film was prepared. Did.

Comparative Example 1

Acrylate hybrid resin (silica acrylate, 4D5-15, DSM Co., Ltd) 1.0 parts by weight of thermal initiator (NA-30 as an epoxy curing agent, Cosmotech), additive (A187, Evonik) 0.1 A hard coating agent, which is a weight part, was coated with 1 um on optical PET to heat-cure and then coated with an adhesive on the back surface of PET to obtain a scattering prevention tape. Thereafter, a UV mold was coated on the hard coating surface, and then cured with UV to prepare a scattering prevention film.

Comparative Example 2

Urethane acrylate oligomer (6 or more functional, molecular weight 600 to 1200, brand name: Miwon MU9800) 0.3 parts by weight of photoinitiator (Irgacure 184), 0.1 parts by weight of additives (A187, Evonik) 0.1 parts by weight of hard coating agent in optical PET 1um After UV curing by coating, an adhesive was coated on the back surface of PET to obtain a scattering prevention tape. Thereafter, a UV mold was coated on the hard coating surface, and then cured with UV to prepare a scattering prevention film.

Comparative Example 3

In Example 1, in the composition of the hard coating layer, in the same manner as in Example 1, except that the urethane acrylate oligomer was changed to 120 parts by weight with respect to 100 parts by weight of the acrylate resin, a scattering prevention film was prepared. Did.

Comparative Example 4

In Example 1, in the composition of the hard coating layer, in the same manner as in Example 1, except that the urethane acrylate oligomer was changed to 30 parts by weight with respect to 100 parts by weight of the acrylate resin, a scattering prevention film was prepared. Did.

Experimental Example: Measurement of adhesion

To evaluate the adhesion between the hard coating layer and the molding resin, a specimen having a width of 20 cm * length of 20 cm was prepared, and then the adhesion between the hard coating layer and the molding resin layer was evaluated. The evaluation of the adhesion was performed by measuring the proportion of the desorbed area among the entire areas generated by the grating when the points where the heart coating layer and the molding resin layer were attached are displayed in a lattice form.

5B if there is no detached area, 4B if the detached area occupies less than 5% of the entire area, 3B if the detached area occupies 5~15% of the entire area, and the detached area 15~35% of the entire area 2B, 1B when the detached region occupies 35 to 65% of the entire region, and 0B when the detached region occupies 65% or more of the entire region.

Adhesion Example 1 5B Example 2 5B Comparative Example 1 2B Comparative Example 2 0B Comparative Example 3 2B Comparative Example 4 3B

When comparing the adhesion of the anti-scattering film according to the embodiment of the present invention and the anti-scattering film according to the comparative example, it can be seen that the adhesion of the anti-scattering film of the present invention is more excellent, the content of the urethane acrylate in the hard coating layer composition When the content of 50 to 100 parts by weight with respect to 100 parts by weight of the acrylate resin was satisfied, it was confirmed that the adhesion between the hard coating layer and the molding resin layer was more excellent as compared with Comparative Examples 3 and 4 which were not.

100: shatterproof film
101: adhesive layer
102: transparent film
103: hard coaching layer
104: molding resin layer

Claims (6)

Adhesive layer;
A transparent film layer on the adhesive layer;
A hard coating layer on the transparent film layer; And
Includes a molding resin layer formed on the hard coating layer,
The resin composition of the hard coating layer is capable of double curing, including 50 to 100 parts by weight of an urethane acrylate oligomer, 0.1 to 3 parts by weight of a photoinitiator, and 0.1 to 3 parts by weight of a thermal initiator relative to 100 parts by weight of an acrylate resin,
The acrylate resin is a methyl acrylate unit 60 parts by weight, butyl methacrylate unit 30 parts by weight, glycidyl methacrylate unit 10 parts by weight of polymerized acrylate resin, characterized in that the shatterproof film. The anti-scattering film according to claim 1, wherein the transparent film comprises one or two or more selected from the group consisting of polyethylene terephthalate, polyether sulfone, and thermoplastic polyurethane. According to claim 1, The hard coating layer has a pencil hardness of B or more, UV resistant film characterized in that the curing at the same time when curing the mold. According to claim 1, The thickness of the hard coating layer is a scattering prevention film, characterized in that 1 ~ 3㎛. delete Preparing a heart coating layer resin composition comprising 50 to 100 parts by weight of an urethane acrylate oligomer, 0.1 to 3 parts by weight of a photoinitiator, and 0.1 to 3 parts by weight of a thermal initiator relative to 100 parts by weight of the acrylate resin;
After applying the resin composition on the optical transparent film, heat curing to form a hard coating layer;
Coating the adhesive composition on the surface of the optical transparent film to which the resin composition is not applied; And
After applying a molding resin on the hard coating layer, irradiating light; Including,
The acrylate resin is a methyl acrylate unit 60 parts by weight, butyl methacrylate unit 30 parts by weight, glycidyl methacrylate unit 10 parts by weight of acrylate resin polymerized in a ratio of scattering prevention film Manufacturing method.

Images