KR102306588B1 - Adhesive protective film and optical member comprising the same - Google Patents

Abstract

urethane resin; at least one of monofunctional (meth)acrylate and polyfunctional (meth)acrylate; and a photoinitiator, wherein the adhesive protective film has a peel force of 5 gf/inch to 25 gf/inch to the glass plate at 25° C. before UV irradiation, and the adhesive protective film is 25 gf/inch after UV irradiation There is provided an adhesive protective film and an optical member including the same, wherein the peeling force for the glass plate at ℃ is 0.5 gf / inch to 5 gf / inch.

Description

Adhesive protective film and optical member including the same

The present invention relates to an adhesive protective film and an optical member including the same.

The optical display device includes a display device including an organic light emitting device and the like. A conventional organic light emitting device includes a glass plate as a substrate. However, recently, interest in wearable or foldable devices is increasing. In response to this interest, an attempt to replace the substrate of the organic light emitting device with a film made of a plastic material from a glass plate is in progress.

The plastic film is thinner and more flexible than the glass plate. Since the panel of the plastic film substrate has poor mechanical properties, it needs to be protected with a protective film in the optical display device manufacturing process. There was a limit to using a conventional protective film for protecting a glass plate as a protective film for a plastic film. When the protective film protecting the plastic film is removed from the plastic film, if the peeling force is high, the panel including the plastic film may be damaged. In particular, since a plastic film is more flexible than a glass plate, it is easy to be damaged when the protective film is peeled off. Therefore, there is a need for a protective film capable of less damaging or changing the shape of the panel including the plastic film even when peeling from the plastic film because the peeling force of the plastic film is low.

Background art of the present invention is disclosed in Korean Patent Application Laid-Open No. 2007-0055363.

SUMMARY OF THE INVENTION It is an object of the present invention to provide an adhesive protective film having a high peeling force on an adherend before UV irradiation and a low peeling force on the same adherend after UV irradiation.

Another object of the present invention is to provide an adhesive protective film having excellent cutting properties without flying, dragging, or dispersing of the adhesive layer during cutting.

Another object of the present invention is to provide an adhesive protective film having excellent wetting property to an adherend when adhering to an adherend, and excellent fairness when cutting because air bubbles do not enter.

Another object of the present invention is to provide an adhesive protective film that does not damage the surface of the adherend when peeled from the adherend after UV irradiation.

The adhesive protective film of the present invention is a urethane resin; at least one of monofunctional (meth)acrylate and polyfunctional (meth)acrylate; and a photoinitiator, wherein the adhesive protective film has a peel force of 5 gf/inch to 25 gf/inch to the glass plate at 25° C. before UV irradiation, and the adhesive protective film is 25 gf/inch after UV irradiation The peel force to the glass plate at ℃ may be 0.5 gf / inch to 5 gf / inch.

The optical member of the present invention may include an optical film and the adhesive protective film of the present invention formed on at least one surface of the optical film.

The present invention provides an adhesive protective film having a high peeling force on an adherend before UV irradiation and a low peeling force on the same adherend after UV irradiation.

The present invention provides an adhesive protective film having excellent cutting properties without flying, dragging, or dispersing of the adhesive layer during cutting.

The present invention provides an adhesive protective film having excellent wetting properties to the adherend when adhering to the adherend, and excellent fairness during cutting because air bubbles do not enter.

The present invention provides an adhesive protective film that does not damage the surface of the adherend when peeled from the adherend after UV irradiation.

BRIEF DESCRIPTION OF THE DRAWINGS It is a schematic diagram of the method of evaluating the cutting property of the adhesive protective film of an Example and a comparative example.
2 is a schematic diagram of a method for evaluating the wetting rate of the adhesive protective film of Examples and Comparative Examples.

It will be described in detail so that a person of ordinary skill in the art can easily carry out the present invention by the following examples. The present invention may be embodied in many different forms and is not limited to the embodiments described herein.

As used herein, “(meth)acryl” may mean acryl and/or methacrylic. As used herein, "copolymer" may include oligomers, polymers, or resins.

The inventor of the present invention has high peel strength to an adherend before UV irradiation, but after UV irradiation, the peel strength to an adherend is relatively lower than before UV irradiation, and has excellent cutability and wetting property to the adherend. As a result of research to implement the adhesive protective film, the adhesive protective film of the present invention was developed and the present invention was completed. When the adhesive protective film of the present invention is adhered to an adherend, the adherend can be protected only with the adhesive protective film, and bubbles do not enter between the adhesive protective film and the adherend. The sieve can be cut to a predetermined size, and there is no flying, dragging, or dispersion of the fine particles of the adhesive protective film during cutting, so fairness can be improved. On the other hand, since the peeling force to the adherend is lowered after UV irradiation, deformation and damage to the adherend can be prevented when peeling from the adherend.

As used herein, the term "adherent" may include a plastic film formed of a polyimide resin, an acrylic resin, a polyethylene terephthalate resin, etc., as well as a glass plate.

Hereinafter, an adhesive protective film according to an embodiment of the present invention will be described.

The adhesive protective film may have a peeling force of 5 gf/inch to 25 gf/inch to the glass plate at 25° C. before UV irradiation. In the above range, it is possible to protect the adherend by being adhered to the adherend without an additional protective film, and it is possible to easily reach a peeling force range in which the adherend can be easily peeled from the adherend by UV irradiation.

In the adhesive protective film, the peeling force to the glass plate at 25° C. after UV irradiation may be significantly lower than the peeling force to the glass plate before UV irradiation. Through this, after being adhered to the adherend, it can be easily peeled from the adherend, and deformation and damage of the adherend can be prevented during peeling. The "UV irradiation" may refer to irradiation with a total energy of 100 mJ/cm ² to 1000 mJ/cm ^{2 per unit area (1 mm 2 ) of the adhesive protective film.}

In one embodiment, the peel force change rate of the following formula 1 may be 50% or more, for example, 60% to 95%: In the above range, the peeling force before UV irradiation and after UV irradiation is appropriate to achieve the effect of the present invention. You can pay enough:

<Equation 1>

Peel force change rate = (PS1-PS2)/PS1 x 100

(In Equation 1, PS1 is the peel force of the adhesive protective film to the glass plate at 25° C. before UV irradiation (unit: gf/inch),

PS2 is the peeling force of the adhesive protective film to the glass plate at 25°C after UV irradiation (unit: gf/inch))

In another embodiment, the peeling force to the glass plate after UV irradiation may be 0.5 gf/inch to 5 gf/inch, specifically 1 gf/inch to 3.5 gf/inch. Within the above range, it can be easily peeled off without damage or deformation of the adherend upon peeling from the adherend.

Adhesive protective film adheres the length x width (50mm x 25 mm) of the end of a rectangular specimen of length x width (150mm x 25mm) to the acrylic plate, and places the other end of the adhesive protective film at an angle of 20° from the acrylic plate Then, when the other end is placed in the direction of the acrylic plate, the time for the adhesive protective film to be completely adhered to the acrylic plate may be less than 10 seconds. In the above range, the wettability of the adhesive protective film to the adherend may be good.

The adhesive protective film is a urethane resin; at least one of monofunctional (meth)acrylate and polyfunctional (meth)acrylate; and a composition for an adhesive protective film including a photoinitiator, and the urethane resin may include a mixture of the first urethane resin and the second urethane resin.

The first urethane resin may include a urethane resin containing one or more urethane bonds in the molecular chain, having a hydroxyl group at the terminal, and not having an isocyanate group at the terminal. The second urethane resin may include a urethane resin containing at least one urethane bond in the molecular chain, having an isocyanate group at the terminal, and not having a hydroxyl group at the terminal. Through this, the first urethane resin and the second urethane resin may increase the peeling force of the adhesive protective film by urethane bonding and curing reaction by a curing catalyst or the like.

The composition for an adhesive protective film is a mixture obtained by preparing a first urethane resin and a second urethane resin, respectively, and then mixing the prepared first urethane resin and the prepared second urethane resin, monofunctional (meth)acrylate, polyfunctional It can be prepared by mixing at least one of functional (meth)acrylates and a photoinitiator with each other.

A composition prepared by mixing at least one of monofunctional (meth)acrylate and polyfunctional (meth)acrylate with a photoinitiator in a product obtained by curing the first urethane resin and the second urethane resin with a curing catalyst. Since the formed adhesive protective film has poor coatability (applicability) and is not cured by a curing catalyst, peeling force may be lowered. In addition, the first urethane resin and the second urethane resin are simultaneously prepared in the same reaction system, and then at least one of monofunctional (meth)acrylate and polyfunctional (meth)acrylate is mixed with a photoinitiator to form a composition The adhesive protective film does not have a lower peeling force even after UV irradiation, and cutting properties and wetting properties to the adherend may not be good. have.

Each of the first urethane resin and the second urethane resin may be a non-(meth)acrylate-type urethane resin that does not have a (meth)acrylate group at the terminal thereof. When at least one of the first urethane resin and the second urethane resin has (meth)acrylate, there may be a problem in that it cannot be used in a foldable display because wettability to an adherend is not improved or flexibility is lowered.

The first urethane resin has a number average molecular weight (Mn) of 1,000 to 20,000, for example 2,000 to 10,000, a weight average molecular weight (Mw) of 5,000 to 50,000, for example 10,000 to 20,000, and a polydispersity of 1.1 to 5.0, for example For example, it may be 1.5 to 3.0. In the above range, the compatibility with the second urethane resin and the applicability of the composition may be excellent and the optical transparency of the adhesive protective film may be improved.

The first urethane resin may be prepared by urethane-reacting polypropylene glycol and isophorone diisocyanate. By using polypropylene glycol, the wettability to the adherend may be good. By using isophorone diisocyanate, the first urethane resin and the second urethane resin are mixed well, so that the compatibility is good, the optical transparency of the adhesive protective film can be improved, and gelation can be prevented. Accordingly, the first urethane resin may include a repeating unit derived from polypropylene glycol and a repeating unit derived from isophorone diisocyanate. In the case of using the first urethane resin prepared by using an aliphatic chain diisocyanate such as hexamethylene diisocyanate in polypropylene glycol, the wetting property, cutting property, and controllability of the peeling force before/after UV of the adhesive protective film are not good. The first urethane resin may not have a repeating unit derived from an aliphatic chain diisocyanate.

The first urethane resin may be prepared by a conventional urethane reaction known to those skilled in the art using polypropylene glycol and isophorone diisocyanate. In this case, the urethane reaction rate can be increased by using a tin-based curing catalyst such as dibutyltin dilaurate. The ratio of the total number of moles of OH groups of polypropylene glycol to the number of moles of NCO groups of isophorone diisocyanate may be OH/NCO=1.01 to 5.0, preferably 1.5 to 2.5. In the above range, it is possible to easily prepare a first urethane resin having no isocyanate group at the terminal and a hydroxyl group at the terminal.

Of the total of 100 parts by weight of the first urethane resin and the second urethane resin, the first urethane resin may be included in an amount of 20 parts by weight to 80 parts by weight, for example, 50 parts by weight to 80 parts by weight. In the above range, there may be an effect that the curing rate of the composition is increased and the wettability of the adhesive protective film is excellent.

The second urethane resin has a number average molecular weight (Mn) of 1,000 to 20,000, for example 2,000 to 10,000, a weight average molecular weight (Mw) of 5,000 to 30,000, for example 5,000 to 25,000, and a polydispersity of 1.5 to 3.0, e.g. For example, it may be 1.8 to 2.5. In the above range, there may be an effect of increasing the crosslinking density upon curing with the first urethane resin.

The second urethane resin may be prepared by urethane-reacting polypropylene glycol and isophorone diisocyanate. By using polypropylene glycol, the wettability to the adherend may be good. By using isophorone diisocyanate, compatibility may be good by mixing well the first urethane resin and the second urethane resin. Accordingly, the second urethane resin may include a repeating unit derived from polypropylene glycol and a repeating unit derived from isophorone diisocyanate. The second urethane resin prepared by using an aliphatic chain diisocyanate such as hexamethylene diisocyanate in polypropylene glycol may have poor wetting and cutting properties. The second urethane resin may not have a repeating unit derived from an aliphatic chain diisocyanate.

The second urethane resin may be prepared by a conventional urethane reaction known to those skilled in the art using polypropylene glycol and isophorone diisocyanate. In this case, the urethane reaction rate can be increased by using a tin-based curing catalyst such as dibutyltin dilaurate. The ratio of the total number of moles of NCO groups of isophorone diisocyanate to the total number of moles of OH groups of polypropylene glycol may be NCO/OH=1.1 to 2.5, preferably 1.5 to 2.0. In the above range, it is possible to easily prepare a second urethane resin having no hydroxyl group at the terminal and an isocyanate at the terminal.

Of the total of 100 parts by weight of the first urethane resin and the second urethane resin, the second urethane resin may be included in an amount of 20 parts by weight to 80 parts by weight, for example, 20 parts by weight to 50 parts by weight. In the above range, there may be an effect of increasing the crosslinking density upon curing with the first urethane resin.

At least one of monofunctional (meth)acrylate and polyfunctional (meth)acrylate is included in the composition for an adhesive protective film to lower the peeling force after UV irradiation compared to before UV irradiation.

Among monofunctional (meth)acrylates and polyfunctional (meth)acrylates, polyfunctional (meth)acrylates can be preferably used. Polyfunctional (meth)acrylates can cure and react with each other by a small amount of UV irradiation compared to monofunctional (meth)acrylates, thereby lowering the peeling force of the adhesive protective film and preventing deformation and damage to the adherend. As the polyfunctional (meth)acrylate, (meth)acrylate having 2 to 10 (meth)acrylate groups may be used.

At least one of monofunctional (meth) acrylate and polyfunctional (meth) acrylate may use (meth) acrylate having a glass transition temperature of 50 ° C. to 200 ° C., for example 50 ° C. to 150 ° C. of the homopolymer. have. In the above range, it is possible to increase the modulus of the adhesive protective film and contribute to the effect of reducing the peeling force after UV irradiation.

For example, the polyfunctional (meth)acrylate is a di(meth) having a C1-C10 alkylene group such as 1,4-butanediol di(meth)acrylate and 1,6-hexanediol di(meth)acrylate. Di(meth)acrylate having a C1 to C10 alkylene group having a C1 to C3 alkyleneoxy group, including acrylate, dipropylene glycol di(meth)acrylate, polyethylene glycol di(meth)acrylate, neo Pentyl glycol di(meth)acrylate, neopentyl glycol adipate di(meth)acrylate, dicyclopentanyl di(meth)acrylate, caprolactone modified dicyclopentenyl di(meth)acrylate, ethylene oxide modified di (meth)acrylate, di(meth)acryloxy ethyl isocyanurate, allylated cyclohexyl di(meth)acrylate, tricyclodecanedimethanol di(meth)acrylate, dimethylol dicyclopentanedi(meth) Acrylate, ethylene oxide-modified hexahydrophthalic acid di(meth)acrylate, tricyclodecane dimethanol (meth)acrylate, neopentylglycol-modified trimethylpropane di(meth)acrylate, adamantane di(meth) ) acrylates or bifunctional (meth)acrylates such as 9,9-bis[4-(2-acryloyloxyethoxy)phenyl]fluorene; Trimethylolpropane tri(meth)acrylate, dipentaerythritol tri(meth)acrylate, propionic acid modified dipentaerythritol tri(meth)acrylate, pentaerythritol tri(meth)acrylate, propylene oxide trifunctional (meth)acrylates such as modified trimethylolpropane tri(meth)acrylate, trifunctional urethane (meth)acrylate, or tris(meth)acryloxyethyl isocyanurate; tetrafunctional (meth)acrylates such as diglycerin tetra(meth)acrylate or pentaerythritol tetra(meth)acrylate; 5-functional (meth)acrylates, such as dipentaerythritol penta (meth)acrylate; And dipentaerythritol hexa (meth) acrylate, caprolactone-modified dipentaerythritol hexa (meth) acrylate or urethane (meth) acrylate (ex. isocyanate monomer and trimethylolpropane tri (meth) acrylate 6-functional (meth) acrylate as a reactant, etc., but is not limited thereto. These can be used alone or in combination of two or more. Preferably, bifunctional, trifunctional, hexafunctional (meth) ) acrylates can be used.

At least one of monofunctional (meth)acrylate and polyfunctional (meth)acrylate is 1 part by weight to 50 parts by weight based on 100 parts by weight of the total of the urethane resin, for example, the total of the first urethane resin and the second urethane resin , for example, may be included in an amount of 5 parts by weight to 30 parts by weight, 10 parts by weight to 20 parts by weight. In the above range, the peeling force to the adherend is lowered by UV irradiation, and there may be no migration of the first urethane resin, the second urethane resin itself, or a cured reaction product thereof.

The photoinitiator may catalyze the photocuring reaction between monofunctional (meth)acrylate and polyfunctional (meth)acrylate after UV irradiation. As the photoinitiator, a conventional photoradical initiator known to those skilled in the art may be used, for example, a benzoin-based, hydroxyketone-based, aminoketone-based or phosphine oxide-based photoinitiator may be used, but is not limited thereto. The photoinitiator may be included in an amount of 0.001 parts by weight to 1 parts by weight, for example, 0.01 parts by weight to 0.5 parts by weight, based on 100 parts by weight of the total of the urethane resin, for example, the first urethane resin and the second urethane resin. In the above range, it does not affect the physical properties of the protective film, catalyzes the photocuring reaction between monofunctional (meth)acrylate and polyfunctional (meth)acrylate, and prevents the optical transparency of the protective film from being lowered due to the remaining amount. can

The composition for an adhesive protective film may further include a curing catalyst.

The curing catalyst catalyzes the curing reaction of the first urethane resin and the second urethane resin, thereby improving processability and preventing changes in physical properties of the protective film due to long-term aging. As the curing catalyst, a conventional curing catalyst known to those skilled in the art may be used, for example, a tin-based catalyst such as dibutyltin dilaurate may be used. The curing catalyst may be included in an amount of 0.001 parts by weight to 1 parts by weight, for example 0.01 parts by weight to 0.5 parts by weight, based on 100 parts by weight of the total of the urethane resin, for example, the first urethane resin and the second urethane resin. In the above range, without affecting the physical properties of the protective film, catalyzing the reaction of the first urethane resin and the second urethane resin, it is possible to prevent the lowering of the optical transparency of the protective film due to the residual amount of the curing catalyst.

The composition for an adhesive protective film may further include at least one of a rework agent and an antistatic agent. The rework agent may help to easily peel the adhesive protective film from the adherend. The antistatic agent can prevent deformation and damage to the adherend by suppressing the generation of static electricity when the adhesive protective film is peeled from the adherend. As the rework agent, a conventional rework agent known to those skilled in the art may be used, for example, a silicone-based rework agent may be used. As the antistatic agent, a conventional antistatic agent known to those skilled in the art may be used, for example, an ionic liquid may be used.

The rework agent may be included in an amount of 0.01 to 10 parts by weight, for example, 0.05 to 5 parts by weight, based on 100 parts by weight of the total of the urethane resin, for example, the first urethane resin and the second urethane resin. Within the above range, the rework function may be performed without affecting the physical properties of the protective film. The antistatic agent may be included in an amount of 0.001 parts by weight to 5 parts by weight, for example, 0.01 parts by weight to 1 part by weight, based on 100 parts by weight of the total of the urethane resin, for example, the first urethane resin and the second urethane resin. In the above range, it is possible to perform an antistatic function without affecting the physical properties of the protective film.

The composition for an adhesive protective film may further include a solvent. The solvent improves the applicability (coating film property) of the composition during the manufacture of the adhesive protective film to smooth the surface of the protective film, thereby improving adhesion with the adherend. As the solvent, a conventional solvent may be used, for example, a ketone-based solvent such as methyl ethyl ketone may be used.

The composition for the adhesive protective film may further include conventional additives known to those skilled in the art. Additives include, for example, leveling agents, surfactants, curing accelerators, ionic liquids, lithium salts, inorganic fillers, softeners, molecular weight regulators, antioxidants, antioxidants, stabilizers, tackifying resins, modifying resins (polyol resins, phenolic resins, Acrylic resins, polyester resins, polyolefin resins, epoxy resins, epoxidized polybutadiene resins, etc.), defoamers, plasticizers, dyes, pigments (colored pigments, extenders, etc.), processing agents, sunscreens, optical brighteners, dispersants, Conventional additives such as heat stabilizers, light stabilizers, ultraviolet absorbers, coagulants, lubricants and solvents may be further included. The additive is 0.001 part by weight to 1 part by weight, specifically 0.003 part by weight to 1 part by weight, specifically 0.005 part by weight to 1 based on 100 parts by weight of the total of the urethane resin, for example, the first urethane resin and the second urethane resin It may be included in parts by weight. In the above range, it is possible to produce an additive effect without affecting the peeling force and reliability of the adhesive film.

The adhesive protective film may not include an isocyanate-type thermosetting agent. When the isocyanate-type thermosetting agent is included, the peeling force may not be sufficiently lowered even after UV irradiation because the peeling force is too high.

The adhesive protective film is coated with a composition for an adhesive protective film to a predetermined thickness on a polyethylene terephthalate film, which is a base film, and left in an oven at 50° C. to 100° C. for 1 minute to 60 minutes to dry and cure the coating layer, Then, another release film is placed on the coating layer and laminated to prepare a laminate, and the obtained laminate may be aged at 50° C. to 100° C. for 1 hour to 48 hours.

The adhesive protective film may have a thickness of 20 μm to 200 μm, for example, 50 μm to 150 μm. In the above range, it may be used as an adhesive protective film.

The adhesive protective film may have a light transmittance of 90% or more. In the above range, it can be used for adhesive protective film applications.

The adhesive protective film may have a glass transition temperature of -150°C to -20°C, preferably -100°C to -50°C. In the above range, there may be an excellent effect of wetting properties of the adhesive protective film and peeling force before UV irradiation.

Hereinafter, an adhesive protective film of another embodiment of the present invention will be described.

The adhesive protective film is a urethane resin; at least one of monofunctional (meth)acrylate and polyfunctional (meth)acrylate; and a photoinitiator, wherein the urethane resin may include a first urethane resin, a second urethane resin, and a third urethane resin. The urethane resin is substantially the same except that it further includes a third urethane resin.

The third urethane resin reacts with monofunctional (meth)acrylate and polyfunctional (meth)acrylate to lower the peeling force to the adherend even in a small amount of UV irradiation, and is a cured reaction product of the first urethane resin and the second urethane resin migration can be prevented. In addition, in the third urethane resin, compared to the case of using only the first urethane resin and the second urethane resin to achieve the same effect, the peeling force to the adherend is improved by relatively reducing the content of the first urethane resin and the second urethane resin. You can prevent it from getting too high.

The third urethane resin may be a (meth)acrylate-type urethane resin having a (meth)acrylate group at the terminal.

The third urethane resin has a number average molecular weight (Mn) of 1,000 to 20,000, for example 2,000 to 10,000, a weight average molecular weight (Mw) of 5,000 to 50,000, for example 8,000 to 20,000, and a polydispersity of 1.5 to 3.0, for example For example, it may be 1.9 to 2.5. Within the above range, there may be an effect of excellent compatibility with the first urethane agent, the second urethane resin, and a monofunctional or polyfunctional (meth)acrylate.

The third urethane resin may be prepared by reacting polypropylene glycol and isophorone diisocyanate with a urethane reaction, and then reacting a compound having a (meth)acrylate group and a hydroxyl group or an isocyanate group. By using polypropylene glycol, the wettability to the adherend may be good. By using isophorone diisocyanate, compatibility may be good by mixing well with the first urethane resin and the second urethane resin. Accordingly, the third urethane resin may include a repeating unit derived from polypropylene glycol and a repeating unit derived from isophorone diisocyanate. The third urethane resin prepared by using an aliphatic chain diisocyanate such as hexamethylene diisocyanate in polypropylene glycol may have poor wetting and cutting properties. The third urethane resin may not include a repeating unit derived from an aliphatic chain diisocyanate. The compound having a (meth) acrylate group and a hydroxyl group or an isocyanate group is one of hydroxyethyl (meth) acrylate, hydroxybutyl (meth) acrylate, isocyanate ethyl (meth) acrylate, and isocyanate propyl (meth) acrylate These may include, but are not limited to.

The third urethane resin may be prepared by a conventional urethane reaction known to those skilled in the art using a compound having polypropylene glycol, isophorone diisocyanate, a (meth) acrylate group and a hydroxyl group or an isocyanate group. In this case, the urethane reaction rate can be increased by using a tin-based curing catalyst such as dibutyltin dilaurate. The ratio of the total number of moles of NCO groups of isophorone diisocyanate to the number of moles of total OH groups of polypropylene glycol may be NCO/OH=0.1 to 5.0, preferably 0.5 to 2.0. Within the above range, it can react with a compound having a (meth)acrylate group and a hydroxyl group or an isocyanate group.

Of the total of 100 parts by weight of the first urethane resin, the second urethane resin, and the third urethane resin, the first urethane resin is 20 parts by weight to 70 parts by weight, for example, 20 parts by weight to 50 parts by weight, the second urethane resin is 10 parts by weight Weight parts to 60 parts by weight, for example, 20 parts by weight to 40 parts by weight, the third urethane resin may be included in an amount of 10 parts by weight to 60 parts by weight, for example, 10 parts by weight to 40 parts by weight. Within the above range, compatibility, wetting property, and cutting property between each component in the adhesive protective film are excellent, and there may be an effect of easy control of peeling force before and after UV irradiation.

The optical member according to an embodiment of the present invention may include an optical film and an adhesive protective film formed on at least one surface of the optical film, and the adhesive protective film may include the adhesive protective film according to embodiments of the present invention. .

The optical film may be a film formed of at least one of a polyethylene terephthalate resin, a polycarbonate resin, a polyimide resin, a poly(meth)acrylate resin, a cyclic olefin polymer resin, and an acrylic resin. The optical film may have a thickness of 50 μm to 250 μm, preferably 50 μm to 100 μm. In the above range, it is possible to support an adhesive protective film.

The optical member may further include a release film (liner) on the other surface of the adhesive protective film. The release film can prevent the adhesive protective film from being contaminated by foreign substances. As the release film, an optical film formed of the same or different material as the above-described optical film may be used. The release film may have a thickness of 10 μm to 100 μm, preferably 10 μm to 50 μm. In the above range, it is possible to support an adhesive protective film.

The optical member according to another embodiment of the present invention includes an optical film and an adhesive protective film formed on at least one surface of the optical film, and the adhesive protective film may include the adhesive protective film according to embodiments of the present invention. .

The optical film may be formed of a polyimide film as a display panel. In one embodiment, the optical film may be composed of a light emitting device layer and a polyimide film formed on at least one surface of the light emitting device layer. An organic insulating film or an inorganic insulating film may be further formed between the optical film and the adhesive protective film.

Hereinafter, the configuration and operation of the present invention will be described in more detail through preferred embodiments of the present invention. However, these are presented as preferred examples of the present invention and should not be construed as limiting the present invention in any sense.

manufacturing example One: first urethane Preparation of resin

In a flask, 2 mol of polypropylene glycol (PPG-3020, Kumho Petrochemical) and 1 mol of isophorone diisocyanate (IPDI, Sigma Aldrich) were added, and dibutyltin dilaurate (DBTDL, Sigma Aldrich) catalyst was mixed with polypropylene glycol. 0.03% by weight was added and mixed with respect to the total of isophorone diisocyanate. The resulting mixture was stirred at room temperature while injecting nitrogen for 30 minutes, and then heated to 61 DEG C, so that the temperature in the flask was 60 DEG C. Polypropylene glycol and isophorone diisocyanate were reacted at the above temperature for 4 hours, and ^{the peak of NCO was confirmed by FTIR at 2200 cm -1} to complete the reaction, whereby the first urethane resin (number average molecular weight: 7775, weight average molecular weight: 15716, polydispersity: 2.0). The prepared first urethane resin has a repeating unit derived from polypropylene glycol, a repeating unit derived from isophorone diisocyanate, contains one or more urethane bonds in the chain, has only a hydroxyl group at the terminal, and does not have an isocyanate group at the terminal does not

manufacturing example 2: Second Urethane Preparation of resin

In a flask, 1 mol of polypropylene glycol (PPG-3020, Kumho Petrochemical) and 3 mol of isophorone diisocyanate (IPDI, Sigma Aldrich) were added, and dibutyltin dilaurate (DBTDL, Sigma Aldrich) catalyst was added to polypropylene glycol. 0.03% by weight was added and mixed with respect to the total of isophorone diisocyanate. The resulting mixture was stirred at room temperature while injecting nitrogen for 30 minutes, and then heated to 61 DEG C, so that the temperature in the flask was 60 DEG C. Polypropylene glycol and isophorone second urethane resin by reacting a diisocyanate at this temperature for 4 hours, and at 2200cm ^-1 by FTIR confirmed a peak of NCO completion of the above reaction (a number-average molecular weight: 9445, weight average molecular weight: 18665, polydispersity: 2.0). The prepared second urethane resin has a repeating unit derived from polypropylene glycol, a repeating unit derived from isophorone diisocyanate, contains one or more urethane bonds in the chain, has only an isocyanate at the terminal, and does not have a hydroxyl group at the terminal .

manufacturing example 3: 3rd Urethane Preparation of resin

In a flask, 2 mol of polypropylene glycol (PPG-3020, Kumho Petrochemical) and 1 mol of isophorone diisocyanate (IPDI, Sigma Aldrich) were added, and dibutyltin dilaurate (DBTDL, Sigma Aldrich) catalyst was added to polypropylene glycol. 0.03 wt% was added and mixed with respect to the total of isophorone diisocyanate and isophorone diisocyanate. The resulting mixture was stirred at room temperature while injecting nitrogen for 30 minutes, and then heated to 61 DEG C, so that the temperature in the flask was 60 DEG C. Polypropylene glycol and isophorone diisocyanate were reacted at the above temperature for 4 hours, and the peak of NCO was confirmed by FTIR at ^{2200 cm -1 to complete the reaction.} Then, by adding 4 mol of 2-isocyanate ethyl methacrylate (MOI) and reacting for 2 hours at the same temperature, confirming ^{the FTIR peak of NCO at 2200 cm -1} to complete the reaction, the third urethane resin (number average Molecular weight: 4887, weight average molecular weight: 10185, polydispersity: 2.1) was prepared.

The prepared third urethane resin has a repeating unit derived from polypropylene glycol and a repeating unit derived from isophorone diisocyanate, contains one or more urethane bonds in the chain, does not have an isocyanate group and a hydroxyl group at the terminal, It has only methacrylate.

Example One

To 10 parts by weight of methyl ethyl ketone (MEK), based on the solid content, 40 parts by weight of the first urethane resin of Preparation Example 1, 25 parts by weight of the second urethane resin of Preparation Example 2, 35 parts by weight of the third urethane resin of Preparation Example 3, 0.05 parts by weight of a dibutyltin dilaurate (DBTDL, Sigma Aldrich) catalyst was mixed. Then, 10 parts by weight of trimethylolpropane triacrylate (TMPTA, glass transition temperature: 62° C.) as a crosslinking agent, 0.25 parts by weight of TPO (diphenyl (2,4,6-trimethylbenzoyl)phosphine oxide) as a photoinitiator, 3 parts by weight of rework agent Z-10 (Soken) and 0.2 parts by weight of antistatic agent FC4400L were added and mixed to prepare a composition for an adhesive protective film.

Example 2 to Example 7

In Example 1, a composition for an adhesive protective film was prepared in the same manner as in Example 1, except that the type and/or content of each component of the composition for an adhesive protective film was changed as shown in Table 1 below.

comparative example One

In a flask, 10 parts by weight of methyl ethyl ketone (MEK), polypropylene glycol (Preminol 53011, number average molecular weight 10000, trifunctional, Asahi glass Co.,) 75 parts by weight, polypropylene glycol (Sannix GP-1500, number average molecular weight) 1500, trifunctional, Sanyo Chemical Ind. Ltd) 25 parts by weight and 10 parts by weight of isopropyl palmitate (Aldrich) were mixed. Then, 40 parts by weight of toluene diisocyanate trimethylolpropane adduct L-45 (Soken), 3 parts by weight of rework agent Z-10, and 0.2 parts by weight of antistatic agent FC4400L were mixed. Then, 0.6 parts by weight of a dibutyltin dilaurate (DBTDL, Sigma Aldrich) catalyst was mixed to prepare a composition for an adhesive protective film.

comparative example 2

In a flask, 10 parts by weight of methyl ethyl ketone (MEK), polypropylene glycol (Preminol 53011, number average molecular weight 10000, trifunctional, Asahi glass Co.,) 75 parts by weight, polypropylene glycol (Sannix GP-1500, number average molecular weight) 1500, trifunctional, Sanyo Chemical Ind. Ltd) 25 parts by weight and 10 parts by weight of isopropyl palmitate (Aldrich) were mixed. Then, 40 parts by weight of toluene diisocyanate trimethylolpropane adduct L-45 (Soken), 10 parts by weight of trimethylolpropane triacrylate, 0.25 parts by weight of TPO, 3 parts by weight of rework agent Z-10, antistatic agent FC4400L 0.2 parts by weight was added. Then, 0.6 parts by weight of a dibutyltin dilaurate (DBTDL, Sigma Aldrich) catalyst was mixed to prepare a composition for an adhesive protective film.

comparative example 3

In a flask, 10 parts by weight of methyl ethyl ketone (MEK), Cyabine SH-109H (polyurethane prepared by urethane reaction of polypropylene glycol and hexamethylene diisocyanate, solid content: 58% by weight, number average molecular weight: 20000) 100 parts by weight, 8 parts by weight of T-501B (hexamethylene diisocyanurate, Toyochem), and 1 part by weight of dibutyltin dilaurate (DBTDL, Sigma Aldrich) catalyst were mixed. Then, 3.0 parts by weight of rework agent Z-10 and 0.2 parts by weight of antistatic agent FC4400L were added and mixed to prepare a composition for an adhesive protective film.

comparative example 4

In a flask, 10 parts by weight of methyl ethyl ketone (MEK), Cyabine SH-109H (polyurethane prepared by urethane reaction of polypropylene glycol and hexamethylene diisocyanate, solid content: 58% by weight, number average molecular weight: 20000) 100 parts by weight, T-501B (hexamethylene diisocyanurate, Toyochem) 12 parts by weight, dipentaerythritol hexaacrylate 30 parts by weight, TPO 4.5 parts by weight, rework agent Z-10 3 parts by weight, antistatic agent FC4400L 0.2 Parts by weight were added and mixed. Then, 1 part by weight of dibutyltin dilaurate (DBTDL, Sigma Aldrich) catalyst was mixed.

The physical properties of the compositions for adhesive protective films prepared in Examples and Comparative Examples were evaluated in Tables 1 and 2 below, and the results are shown in Tables 1 and 2 below.

(1) Peel strength (peel strength, peel strength before UV irradiation, unit: gf/inch): degassing the composition for an adhesive protective film, and applying the obtained composition to a thickness of 75 μm on a polyethylene terephthalate film, and at 130° C. The applied layer was dried and cured by standing in an oven for 4 minutes. Then, a silicone coating-release film (thickness: 38 μm) was placed on the application layer (thickness: 75 μm) and laminated to prepare a laminate. The resulting laminate was aged at 50° C. for 24 hours.

Then, the laminate was cut to length x width (150 mm x 25 mm) to obtain three specimens. The silicone coating-release film was peeled off from each specimen to expose the adhesive protective film, and the PET film and the adhesive protective film were laminated on a glass plate through the adhesive protective film and pressed with a 2 kg roller. Then, the peeling force was measured when peeling the adhesive protective film from the glass plate using a texture analyzer at a peeling rate of 2400mm/sec, a peeling angle of 180°, and a peeling temperature of 25°C, and an average of the peeling forces was obtained.

(2) Peeling force after UV irradiation (unit: gf/inch): Three specimens were prepared in the same manner as in (1). Then, UV was irradiated with a total energy of 500 mJ/cm ² per unit area (1 mm ^{2 ) with a metal halide lamp.} At this time, UV irradiation was irradiated from the PET film side. Then, the peel force was measured in the same manner as in (1), and the average of the peel force was obtained.

(3) Cuttability: Three specimens were prepared in the same manner as in (1). The silicone coating-release film was peeled off from the specimen to expose the adhesive protective film. 1, in the laminate of the PET film (1) and the adhesive protective film (2), on one side of the adhesive protective film (2), a stainless pencil (diameter 1 mm) (3) used for measuring pencil hardness is applied to the adhesive protective film (2) It was placed at an angle of 45° with respect to the surface and was scraped while moving at a load of 1 kg, a speed of 48 mm/min, and 25°C. At this time, if there are no particles formed on the surface of the adhesive protective film or if thin thread-like residue is not formed and the adhesive protective film is scratched, '○', particles are formed in irregular shapes and sizes on the surface of the adhesive protective film and the adhesive layer If it was scratched, it was rated as 'X'.

(4) Wetting rate: Three specimens were prepared in the same manner as in (1). The silicone coating-release film and the PET film were peeled off from the specimen to obtain an adhesive protective film. Referring to FIG. 2 , only the end end 5-1 of the adhesive protective film 5 was adhered to the acrylic plate 4 with a length of 50 mm. Then, in a state where the other end (5-2) of the adhesive protective film (5) is not adhered to the acrylic plate (40), the acrylic plate (4) and the adhesive protective film (5) have an angle (θ) of 20 The angle was held and held. Then, when the other end (5-2) of the adhesive protective film (50) is placed in the direction of the acrylic plate (4) (referred to as 0 seconds), the adhesive protective film (5) is completely attached to the acrylic plate (4). The time until adhesion was measured. If the time was less than 10 seconds, it was evaluated as ○, and if the time was more than 10 seconds, it was evaluated as x.

(5) Wetting air gap: The wetting air gap evaluates the wettability of the adhesive protective film to the adherend. A patterned polyimide film in which a pattern having a height of 1 μm and a flat surface were continuously formed was used as an adherend. The adhesive protective films prepared in Examples and Comparative Examples were laminated on the patterned polyimide film using a 2 kg roll. Whether an agir gap was formed between the pattern and the flat surface among the bonding surfaces of the adhesive protective film and the patterned polyimide film was evaluated using an optical microscope. If air bubbles were not seen, it was evaluated as '○', and if air bubbles were visible, it was evaluated as 'x'.

Example One 2 3 4 5 6 7 1st urethane resin 40 45 50 50 60 45 45 2nd urethane resin 25 30 35 40 40 30 30 3rd urethane resin 35 25 15 10 0 25 25 catalyst 0.05 0.05 0.05 0.05 0.05 0.05 0.05 SR833S 0 0 0 0 0 10 0 TMPTA 10 10 10 10 0 0 0 DPHA 0 0 0 0 15 0 10 photoinitiator 0.25 0.25 0.25 0.25 0.25 0.25 0.25 rework system 3 3 3 3 3 - - antistatic agent 0.2 0.2 0.2 0.2 0.2 - - menstruum 10 10 10 10 10 7 7 Peeling force before UV irradiation 19.8 12.1 10.1 6.1 10.3 23.2 21.5 Peeling force after UV irradiation 1.9 1.8 1.8 1.6 3.1 2.1 1.8 tailorability ○ ○ ○ ○ ○ ○ ○ wetting speed ○ ○ ○ ○ ○ ○ ○ wetting air gap ○ ○ ○ ○ ○ ○ ○

Comparative Example 1 Comparative Example 2 Comparative Example 3 Comparative Example 4 Preminol 53011 75 75 0 0 Sannix GP-1500 25 25 0 0 Isopropyl palmitate 10 10 0 0 Cyabine SH-109H 0 0 100 100 Thermal initiator (T-501B) 0 0 8 12 Thermal Initiator (L-45) 40 40 0 0 catalyst 0.6 0.6 One One TMPTA 0 10 0 0 DPHA 0 0 0 30 photoinitiator 0 0.25 0 4.5 rework system 3 3 3 3 antistatic agent 0.2 0.2 0.2 0.2 menstruum 10 10 10 10 Peeling force before UV irradiation 4.3 6.2 6.5 13.2 Peeling force after UV irradiation 4.3 7.2 5.8 8.0 tailorability x x x x wetting speed x x x x wetting air gap x x x x

*From Table 1 and Table 2

TMPTA is trimethylolpropane triacrylate (the glass transition temperature of the homopolymer is 62℃)

SR833S is tricyclodecane dimethanol diacrylate (glass transition temperature of homopolymer is 110℃)

DPHA is dipentaerythritol hexaacrylate (the glass transition temperature of homopolymer is 54℃)

As shown in Table 1, the adhesive protective film of the present invention has a high peeling force to an adherend before UV irradiation and a high peeling force to the same adherend after UV irradiation, so that it can be used as a protective film for a process on an adherend. can In addition, the adhesive protective film of the present invention has excellent cutting properties because there is no flying, dragging, or dispersion of the adhesive protective film particles when cutting, and has excellent wetting properties to the adherend when adhering to the adherend and does not contain air bubbles. Fairness was excellent.

On the other hand, as in Comparative Examples 1 and 2, the first urethane resin and the second urethane resin are simultaneously prepared in the same reaction system, or at least one of monofunctional (meth)acrylate and polyfunctional (meth)acrylate The adhesive protective film formed of the composition prepared by further mixing did not lower the peeling force even after UV irradiation, and had poor cutting properties and wettability to the adherend.

In addition, as in Comparative Examples 3 and 4, the adhesive protective film prepared from a composition including a urethane resin prepared from hexamethylene diisocyanate instead of isophorone diisocyanate had poor wetting properties and cutability.

Simple modifications or changes of the present invention can be easily carried out by those of ordinary skill in the art, and all such modifications or changes can be considered to be included in the scope of the present invention.

Claims (15)

urethane resin; at least one of monofunctional (meth)acrylate and polyfunctional (meth)acrylate; And an adhesive protective film formed of a composition comprising a photoinitiator,
The adhesive protective film has a peel force of 5 gf/inch to 25 gf/inch to the glass plate at 25° C. before UV irradiation,
The adhesive protective film has a peel force of 0.5 gf/inch to 5 gf/inch to the glass plate at 25° C. after UV irradiation,
The urethane resin is non- (meth) comprising a acrylate-type urethane resin, the adhesive protective film.
The adhesive protective film according to claim 1, wherein the adhesive protective film has a peel force change rate of 50% or more of the following formula:
<Equation 1>
Peel force change rate = (PS1-PS2)/PS1 x 100
(In Equation 1, PS1 is the peel force of the adhesive protective film to the glass plate at 25° C. before UV irradiation (unit: gf/inch),
PS2 is the peeling force of the adhesive protective film to the glass plate at 25°C after UV irradiation (unit: gf/inch)).
According to claim 1, wherein the adhesive protective film is adhered to the acrylic plate with the end of the rectangular specimen of length x width (150mm x 25mm) as the contact area length x width (50mm x 25mm), and the other end of the adhesive protective film When the end is positioned at an angle of 20° from the acrylic plate and then the other end is placed in the direction of the acrylic plate, the time for the adhesive protective film to be completely adhered to the acrylic plate is less than 10 seconds, the adhesive protective film .
The adhesive protective film according to claim 1, wherein the urethane resin has a repeating unit derived from polypropylene glycol and a repeating unit derived from isophorone diisocyanate.
The adhesive protective film according to claim 1, wherein the urethane resin does not have a repeating unit derived from an aliphatic chain diisocyanate.
delete The adhesive protective film according to claim 1, wherein the urethane resin comprises a mixture of a first urethane resin having no isocyanate group at the terminal and a hydroxyl group at the terminal and a second urethane resin having no hydroxyl group at the terminal and an isocyanate at the terminal. .
The method according to claim 7, wherein the first urethane resin is 20 to 80 parts by weight, and the second urethane resin is 20 to 80 parts by weight of the total of 100 parts by weight of the first urethane resin and the second urethane resin. Which will be included, the adhesive protective film.
The adhesive protective film according to claim 7, wherein the composition further comprises a (meth)acrylate-type third urethane resin having a (meth)acrylate group at a terminal thereof.
The adhesive protective film according to claim 9, wherein the (meth)acrylate-type third urethane resin has a repeating unit derived from polypropylene glycol and a repeating unit derived from isophorone diisocyanate.
10. The method of claim 9, wherein the first urethane resin is 20 parts by weight to 70 parts by weight of the total of 100 parts by weight of the first urethane resin, the second urethane resin, and the third urethane resin, and the second urethane resin is 10 parts by weight. To 60 parts by weight, the third urethane resin is included in 10 parts by weight to 60 parts by weight, the adhesive protective film.
The adhesive protective film according to claim 1, wherein at least one of the monofunctional (meth)acrylate and the polyfunctional (meth)acrylate is included in an amount of 1 to 50 parts by weight based on 100 parts by weight of the urethane resin. .
The adhesive protective film of claim 1, wherein the adhesive protective film further comprises at least one of a rework agent, a curing catalyst, and an antistatic agent.
The adhesive protective film according to claim 1, wherein the composition does not contain an isocyanate-type thermosetting agent.
optical film; and
An optical member comprising the adhesive protective film of any one of claims 1 to 5 and 7 to 14 formed on one surface of the optical film.

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