WO2012173397A2

WO2012173397A2 - Liti donor film

Info

Publication number: WO2012173397A2
Application number: PCT/KR2012/004685
Authority: WO
Inventors: Chong Won Kim; Sang-Hyun Baek; Si Min Kim
Original assignee: Kolon Industries, Inc.
Priority date: 2011-06-15
Filing date: 2012-06-14
Publication date: 2012-12-20
Also published as: WO2012173397A3

Abstract

Provided is a laser induced thermal imaging (LITI) donor film including: a base film, a primer layer, a light-to-heat conversion layer, an interlayer, and a transfer layer, wherein the light-to-heat conversion layer includes a resin composition including a thermosetting resin and a light-to-heat conversion material, and the interlayer includes a UV curable resin and has a surface energy of 35mN/m or less.

Description

LITI DONOR FILM

The present invention relates to a laser induced thermal imaging (LITI) donor film, and more particularly to an LITI donor film having a laser induced thermal imaging forming element to be used in an LITI method or a process similar to the LITI method.

A recent development trend in the technology of a display device is to provide excellent visibility while using energy in a small amount. Therefore, a development in the display device using an organic light emitting device (OLED) known to consume energy less than that of the existing light emitting scheme has been competitively created.

In order to implement a full color display of the display device using the OLED, a method of patterning the color to a light emitting device is significantly important, and as a result, according to a method of forming an organic layer of the OLED determining the color of the light emitting device, a difference in implemented effect is generated. The method of forming the organic layer in the OLED include a deposition method, an inkjet scheme, a laser induced thermal imaging (LITI) method, or the like. The laser induced thermal imaging method, which is in commonly used for LITI method, converts a light emitted from a laser to thermal energy, and transfers a transfer layer to an OLED substrate using the converted thermal energy, thereby forming the organic layer in the OLED. The transfer method is described in Korean Patent No. 10-0700828, or the like. The LITI method has advantages such as forming of a pattern having high resolution, uniformity of a film thickness, ability of implementing a multilayer, and expandability to a mother glass having a large size.

In the LITI method, a decisive medium converting the light to the thermal energy to form the pattern on the substrate of the light emitting device is a LITI donor film including a transfer layer having a red pixel region (R), a green pixel region (G), a blue pixel region (B). The LITI donor film has a structure in which a base film, a light-to-heat conversion layer, and a transfer layer are sequentially laminated. The LITI donor film selectively includes an interlayer between the light-to-heat conversion layer and the transfer layer in order to prevent the material contained in the light-to-heat conversion layer from being transferred to the transfer layer.

In the case of irradiating the laser to the LITI donor film in the LITI process, light energy of the laser is converted to the thermal energy in the light-to-heat conversion layer, volumetric expansion in the light-to-heat conversion layer and the interlayer is generated by the thermal energy, such that the transfer layer is transferred on the OLED substrate by the volumetric expansion.

[Related Art Document]

(Patent Document 1) Korean Patent No. 10-0700828 (March 21, 2007)

The present inventors completed the present invention based on the fact that a surface transferred from a transfer layer may be smoothly and uniformly formed by uniformly expanding the volume of a light-to-heat conversion layer, in order to preferably implement a transferred patterns. An object of the present invention is to provide an LITI donor film capable of allowing a surface transferred from the transfer layer to be smooth and uniform when a transfer layer is transferred by the LITI method.

In addition, the present inventors completed the present invention based on the fact that the transfer layer may be uniformly formed even at a bent portion in the case in which an acceptor has a 3D shape, by optimizing pencil hardness of the interlayer. That is, another object of the present invention is to provide an LITI donor film having an interlayer having excellent form following capability.

In order to accomplish the object, the present invention relates to a laser induced thermal imaging (LITI) donor film including: a base film, a primer layer, a light-to-heat conversion layer, an interlayer, and a transfer layer, which is characterized by compositions and thicknesses of the light-to-heat conversion layer and the interlayer.

In particular, the present inventors searched in order to solve problems that, in the case of using a UV curable resin in the light-to-heat conversion layer, foaming may not occur due to excessive curing or there may be generated an edge open phenomenon on a transferred surface after being transferred, due to the foaming, that is, a phenomenon in which transferring is not performed at a bent portion or an angulated edge portion in the case in which the transfer layer is transferred as shown in FIG. 1, and then, the present inventors have found that the edge open phenomenon is improved using a thermosetting resin instead of the UV curable resin. FIG. 1 is a cross-sectional view for describing an edge open phenomenon generated on a transferred surface after being transferred, which shows an acceptor 200, a transfer layer 300, and an edge open 100.

However, in the case where a light-to-heat conversion material is not uniformly distributed but partially coheres when the thermosetting resin is used to form the light-to-heat conversion layer, at the time of laser irradiation, excessive heat may be generated at the cohesion portion, which is then burn, or a telegraphic phenomenon in which a surface form of the conversion layer is directly exhibited on the interlayer after coating the interlayer may be generated.

In addition, in the case in which a layer forming pixels is coated on the light-to-heat conversion layer, and is then transferred, the surface of the transfer layer is not smooth. As a result, in order to solve the problem as described above, a coated amount after drying of the light-to-heat conversion layer is controlled to be 1 to 3.5g/㎡, a thickness of the interlayer is controlled to be 1.0 to 3.5㎛, and a content of the light-to-heat conversion material used in the light-to-heat conversion layer is controlled to be 20 to 40wt%.

In addition, in order that the light-to-heat conversion material prevents excessive heat from being partially generated due to the cohesion, a first kneading or mixing, a second milling, and a third filtering processes are performed to solve the cohesion problem. In addition, in order to maximize a milling effect, oxidized carbonblack may be used or an additive, such as an aluminum based dispersant or the like, may be utilized. The present inventors found that, by solving carbon black cohesion problem, the transfer layer has a significantly smooth surface and the edge open phenomenon is not generated, so that the transferring is successfully performed, and then completed the present invention.

The transfer layer after being transferred has a significantly smooth surface and the edge open phenomenon is not generated, which is important to form a display having a high resolution. As described above, with the LITI donor film according to the present invention, in the case in which the coated amount after drying of the light-to-heat conversion layer is controlled to be 1 to 3.5g/㎡, a thickness of the interlayer is controlled to be 1.0 to 3.5㎛, and a content of the light-to-heat conversion material used in the light-to-heat conversion layer is controlled to be 20 to 40wt%, the surface energy of the light-to-heat conversion layer is 35mN/m or less, and surface roughness thereof is 20nm or less. In the case in which the surface roughness of the light-to-heat conversion layer is within the range described above, the surface of the transfer layer is smoothly and uniformly formed.

In order to accomplish the object, the present invention relates to a laser induced thermal imaging (LITI) donor film including: a base film, a primer layer, a light-to-heat conversion layer, an interlayer, and a transfer layer, which is characterized by hardness of the interlayer.

In particular, the present inventors have found that in the case in which the hardness of the interlayer is high, form following capability is decreased, such that an edge open phenomenon where transferring is not performed at an acceptor portion having a bent portion or a phenomenon where transferring is not uniformly performed along a bent portion even though it is transferred is generated, thereby lowering a resolution of a display.

The study for solving this problem confirmed that a surface roughness of the interlayer has a significant influence. Therefore, in the case in which a pencil hardness of the interlayer is over H, the form following capability is decreased to easily generate the edge open phenomenon, and even though the edge open phenomenon is not generated, a bent surface of a bent acceptor is not uniformly filled to lower the resolution of the display in the end. Therefore, in order to solve the problem, it is preferable that the pencil hardness of the interlayer is H or lower. More preferably, the pencil hardness is HB or lower.

In one general aspect, a laser induced thermal imaging (LITI) donor film includes: a base film, a primer layer, a light-to-heat conversion layer, an interlayer, and a transfer layer, wherein the light-to-heat conversion layer includes a resin composition including a thermosetting resin and a light-to-heat conversion material, and the interlayer includes a UV curable resin, a silicon-based resin or a fluorine-based resin and has a surface energy of 35mN/m or less.

The interlayer may have a surface energy of 18mN/m to 35mN/m.

The interlayer may have a surface energy of 18mN/m to 25mN/m.

The light-to-heat conversion layer may have a surface-roughness (Ra) of 20nm or less.

In the light-to-heat conversion layer, the thermosetting resin may be a polyurethane based resin and the light-to-heat conversion material is carbon-black.

The polyurethane based resin may be selected from polyesterpolyurethane and polycarbonatepolyurethane.

The light-to-heat conversion material may be included in an amount of 20 to 40 wt%.

The light-to-heat conversion material may be dispersed in any one or two or more resins selected from polyvinylchloride, polyvinylchloride polyvinylacetate copolymer, and thermosetting polyurethane, and a solvent.

The light-to-heat conversion layer may further include a thermoplastic resin in an amount of no more than 50wt% based on the entire resin composition.

The light-to-heat conversion layer may have a coated amount after drying of 1 to 3.5g/㎡.

The interlayer may have a thickness of 1.0 to 3.5㎛.

In another general aspect, a laser induced thermal imaging donor film includes: a base film, a primer layer, a light-to-heat conversion layer, an interlayer, and a transfer layer, wherein the interlayer has a pencil hardness of H or lower.

The interlayer may be obtained by coating and curing the UV curable resin composition.

The UV curable resin composition may include at least one UV curable resin selected from a group consisting of urethaneacrylate, epoxyacrylate, polyester acrylate and siliconacrylate, and an initiator.

The UV curable resin composition may further include at least one thermoplastic resin selected from a group consisting of a polyurethane resin, an acrylate based resin, a polyester resin, and urethaneacrylate copolymer.

The UV curable resin composition may further include a fluorine-based additive or a silicon-based additive.

With the LITI donor film according to the present invention, the interlayer shape having the uniform surface may be secured by selecting the optimal thickness of the interlayer according to the surface roughness of the light-to-heat conversion layer. Therefore, in the case in which the final transfer layer is transferred, the uniform transfer surface may be obtained, thereby optimizing the resolution of the display.

In addition, the present invention may provide an LITI donor film having the excellent form following capability. Therefore, in the case in which the final transfer layer is transferred, the uniform transfer surface having excellent form following capability may be obtained, thereby eventually optimizing the resolution of the display.

The above and other objects, features and advantages of the present invention will become apparent from the following description of preferred embodiments given in conjunction with the accompanying drawings, in which:

FIG. 1 is a cross-sectional view for describing an edge open phenomenon generated on a transfer surface of the related art; and

FIG. 2 is a cross-sectional view showing an embodiment of a lamination structure of a laser induced thermal imaging (LITI) donor film according to the present invention.

[Detailed Description of Main Elements]

10 : base film

20: primer layer

30 : light-to-heat conversion layer

40 : interlyaer

50 : transfer layer

100 : edge open

200 : acceptor

300 : transferlayer

Hereinafter, referring to the drawings, a laser induced thermal imaging (LITI) donor film of the present invention will be described in detail.

As shown in FIG. 2, a base film 10, a primer layer 20, a light-to-heat conversion layer 30, an interlayer 40 and a transfer layer 50 are sequentially laminated from below.

A first aspect of the present invention provides a laser induced thermal imaging (LITI) donor film including the base film 10, the primer layer 20, the light-to-heat conversion layer 30, the interlayer 40, and the transfer layer 50, and having surface energy of 35mN/m or lower, wherein the light-to-heat conversion layer 30 includes a resin composition including a thermosetting resin and a light-to-heat conversion material, and the interlayer 40 includes a UV curable resin, a silicon-based resin, or a fluorine-based resin.

A second aspect of the present invention provides the LITI donor film including the base film 10, the primer layer 20, the light-to-heat conversion layer 30, the interlayer 40, and the transfer layer 50, wherein the interlayer has a hardness of H or lower.

Hereinafter, a configuration of each layer of the LITI donor film of the present invention will be described in detail.

Base Film

The base film in the present invention may be a glass, a transparent film or a polymer film. An example of the polymer film may include polyester, polycarbonate, polyolefin, polyvinyl resins, or the like, which is not limited thereto. More specifically, it is preferable to use polyethyleneterephthalate, polyethylenenaphthalate, or the like, because they have excellent processibility, thermal stability, and transparence. More preferably, a material having a light transmittance of 90% or higher may be used in order to increase the transparence of the light irradiated in performing a LITI method.

A surface of the base film may be modified by a surface treatment known to those skilled in the art, such as corona, plasma, or the like, to thereby control adhesion, surface tension, or the like, at the time of performing a subsequent process.

In addition, in the base film of the present invention, cohered particles positioned inside and outside and particles having different kinds of components from a gel component or a base component, preferably, have a size of 1㎛ or smaller. In the case in which the size thereof is larger than 1㎛, a laser is scattered and diffracted due to the particles or the gel component in a transfer process using the laser, such that the energy of the laser may be not transmitted to a desired portion, thereby generating a phenomenon in which the transferring is not performed.

The thickness of the base film is 0.025 to 0.15mm, and more particularly, 0.05 to 0.1mm, which is not limited thereto.

Primer Layer

The primer layer of the present invention controls delivery of temperature between the base film and a layer adjacent thereto, improves adhesion between the base film and the layer adjacent thereto, and controls delivery of a radiation forming an image to the light-to-heat conversion layer. In the case of forming the primer layer, a phenomenon in which the base and the light-to-heat conversion layer are separated from each other in the transfer process using the laser may be improved, which is more preferable. A material suitable for the primer layer may be any one selected from an acryl-based resin, a polyurethane-based resin, and a polyester-based resin, or a mixed resin thereof. In the case in which heat resistance adhesion between the primer layer and the base film or between the primer layer and the light-to-heat conversion layer is poor, the base film and the light-to-heat conversion layer may be separated from each other in the transfer process using the laser.

More specifically, the primer layer of the present invention may be formed by being coated on one surface or on both surfaces of the base film by an in-line coating process at the time of forming the base film.

That is, in the case in which the base film of the present invention is a polyethyleneterephthalate film, the primer layer may be formed by coating a water dispersible primer coating liquid on the base film and performing uniaxial or biaxial stretching in the stretching of the film.

The water dispersible primer coating liquid may be used without limitation as far as it can be used in the corresponding art. Preferable is a water dispersible primer coating liquid formed of a resin having a small difference in refractive index from the polyethyleneterephthalate film which is the base film, since it improves the light transmittance. A water dispersible primer coating liquid including acryl-based resin, a polyurethane-based resin, a polyester-based resin, or the like may be preferable as an example thereof.

The thickness of the primer layer may be preferably 0.01 ~ 0.5 ㎛, which is not limited thereto.

Light-To-Heat Conversion layer; LTHC layer

The light-to-heat conversion layer of the present invention is a layer absorbing the light in infrared ray-visible ray region to convert a portion of the light to the heat, which includes a resin composition including a thermosetting resin and a light-to-heat conversion material.

The resin composition of the present invention may be made of a thermosetting resin alone or a mixed resin of the thermosetting resin and a thermoplastic resin. In the case of using the mixed resin of the thermosetting resin and the thermoplastic resin, the thermosetting resin may include 50wt% or larger of the entire resin component, including a curing agent. In the case in which the content of the thermosetting resin is less than 50wt%, anti-solvent property is lowered, such that a solvent of the interlayer may be permeated to the light-to-heat conversion layer at the time of coating the interlayer, and the light-to-heat conversion material is not smoothly dispersed in a dispersing process thereof, such that a pinhole may be generated at the time of coating.

It is preferable that the thermosetting resin in the resin composition includes a polyurethane-based thermosetting resin. Specific examples of the thermosetting polyurethane may include polycarbonate polyurethane, polyester polyurethane, polyurethane, or the like. It is preferable that a glass transition temperature (T_g) of the polyurethane resin is 10℃ or higher, and more specifically, T_g is 10 to 50℃. In the case in which the glass transition temperature is lower than the range as described above, a coating layer may be partially transferred to the opposite surface in an aging process after coating the light-to-heat conversion layer. In the case in which the glass transition temperature is higher than the range, at the time of laser irradiation, a volumetric expansion is decreased, such that transferring to a desired shape may be difficult.

An example of the curing agent may include isocyanate-based curing agent, peroxide, epoxy-based cross linker, a metal chelate-based cross linker, a melamine-based cross linker, an aziridine-based cross linker, a metal salt, or the like. These cross linkers may be used alone for 1 kind, or in combination for 2 kinds thereof. In addition, the thermoplastic resin may be added to this composition.

The thermoplastic resin may be used in an amount smaller than the total amount of the thermosetting resin and the cross linker solid content based on the solid content. Specifically, the thermoplastic resin is used in an amount less than 50wt% of the entire resin composition. As the thermoplastic resin, polyvinylchloridevinylacetate copolymer, polyvinylchloridehomopolymer, polymethylmethacrylate, isobutylmethacrylate, polybutylmethacrylate, polymethylacrylate-butylacrylatecopolymer, or the like, may be used. It is preferable that the glass transition temperature thereof is 40℃ or higher. In the case in which the glass transition temperature is less than 40℃, a blocking phenomenon may be generated.

The light-to-heat conversion material is a material, which is a material absorbing an incident laser light and converting it to heat. An example of the light-to-heat conversion material may include dyes such as a visible ray dye, an ultraviolet ray dye, an infrared dye, a fluorescent dye, and a radiation polarization dye, or the like, a pigment, a metal, a metal compound, a metal film, carbonblack, a metal oxide, a metal sulfide, or the like, and more preferably, the carbonblack.

In addition to the carbonblack, the dyes such as the visible ray dye, the ultraviolet ray dye, the infrared dye, the fluorescent dye, the radiation polarization dye, or the like, the pigment, an organic dye, an inorganic dye, a metal, a metal compound, a metal film, an iron cyanide pigment, a phthalocyanine pigment, a phthalocyanine dye, a cyanine pigment, a cyanine dye, a metal dithiolene pigment, a metal dithiolene dye, and other absorption material, or the like, may be further added thereto, as needed.

Preferably, the carbonblack has an average particle size of 10 ~ 30nm, thereby obtaining a smooth surface. In addition, the carbonblack is firstly dispersed in any one or two or more resins selected from polyvinylchloride, polyvinylchloride-polyvinylacetate copolymer, and thermosetting polyurethane to perform a surface treatment, thereby significantly improving dispersibility in the resin.

The first dispersion may be performed by adding the carbonblack to the resin such as polyvinylchloride, or the like, and using a method such as kneading, mixing, or the like. The kneading may be performed by including a solvent, and by using a kneading machine after preparing a preparation liquid having a solid content of 30 to 70wt%, in the case in which the solid content is less than 30wt%, viscosity may be lowered to decrease the degree of dispersion of the carbon, and in the case in which the solid content is more than 70wt%, excessive torque may be generated to disturb the dispersion. Additional milling process and filtering process may be further performed to the kneaded crude liquid for optimizing the degree of dispersion. It is preferable that as the solvent used in the kneading, a solvent capable of dissolving the resin according to the kind of the resin may be selected, and more specifically, a mixed solvent obtained by mixing toluene, methylethylketone, and cyclohexanone at a weight ratio of 1~5:1~5:1~5 may be used.

In the present invention, the content of the light-to-heat conversion material is preferably included in an amount of 20 to 40wt%. In the case in which the content of the light-to-heat conversion material is lower than 20wt%, a transfer process using the laser has a limitation in expanding the light-to-heat conversion layer, such that a desired pattern may not be uniformly transferred. In the case in which the content is higher than 40wt%, excessive heat is generated in the laser transfer process to burn the light-to-heat conversion layer, such that the transferring may not be performed.

The light-to-heat conversion layer in the present invention may be formed by a kneading process, a milling process, a filtering process, and a coating process, or by a milling process, a filtering process, and a coating process. The kneading process and the milling process may be performed for optimizing the degree of dispersion of the particles. The milling may performed by employing various methods such as a ring mill, a sand mill, and the like.

The milling process may be variously used. In the case of using the ring mill, a crude liquid obtained by adding the remaining resin and solvent to the firstly kneaded crude liquid such that the entire liquid has a solid content of 10wt% to 20wt%, or a resin/carbonblack/solvent mixture liquid (having a solid content of 10wt% to 20wt%) is injected to a main container of a milling machine, zirconium particles of 0.5~2.0mm fill into a ring part in volume by 50 to 80%, and then agitation is performed. The agitation is double performed. One agitation is performed so that the solution in a main milling container is injected into the ring part while being circulated, and the other agitation is performed so as to disperse the particles in the ring part. The particles filling into the ring part may be other particles for milling besides the zirconium. The milling may be performed in various stages, as needed. After a first milling is performed by filing of zirconium particles of 2.0mm, a second milling is performed by filling of particles of 1.5mm, and a third milling is performed by filling of particles of 0.5mm, thereby uniformly dispersing carbon black particles.

Alternatively, a milling machine sequentially filled with the particles by respective sizes may be used to sequentially perform the milling.

At the time of milling, the solid content is preferably included in 10wt% to 20wt%. Although there is some difference according to the composition ratio of the resin, in the case in which the content is lower than 10wt%, particle dispersing efficiency may be decreased, and in the case in which the content is higher than 20wt%, liquid stability of the milled solution may be decreased.

The filtering process may remove large particles having a particle size of 2.5㎛ or larger. An example of a coating process may include a bar coating process, a die coating process, and a roll coating process. Various coating methods may be applied, if needed. In the case in which additional cross linking is separately needed after the coating process, the degree of cross linking may be controlled through separate aging.

The light-to-heat conversion layer is formed by being coated and dried on a substrate including the primer layer. Since the layer is thermosetting type, a cross linking treatment is needed by an appropriate heat treatment. The cross linking treatment may be performed with the drying process at a temperature for drying process, and the cross linking treatment may be separately performed after the drying process.

It is preferable that the light-to-heat conversion layer has a coated amount after drying of 1 to 3.5g/㎡. In the case in which the coated amount after drying, of the light-to-heat conversion is smaller than 1g/㎡, the light-to-heat conversion layer may be burned in the transfer process, and in the case in which the coated amount after drying is larger than 3.5g/㎡, heat is not appropriately transferred, such that the transfer may not be sufficiently performed.

In addition, it is preferable that the light-to-heat conversion layer has surface-roughness (Ra) of 20nm or less, and more preferably, 10 to 20nm. In the case in which the surface roughness thereof is more than 20nm, the surface of the transfer layer may not be smooth and uniform.

Interlayer

An interlayer in the present invention is formed in order that when the transfer layer is transferred by heat generated from the light-to-heat conversion layer, the light-to-heat conversion material present in the light-to-heat conversion layer is transferred together, and in order that the heat generated from the light-to-heat conversion layer is transferred to the transfer layer to burn the light-to-heat conversion layer due to the heat.

Preferably, as the interlayer in the present invention, a UV curable resin may be used. For improving form shape following capability, a thermoplastic resin having no tack at a room temperature may be mixed thereto for use.

In addition, since the interlayer needs to perform a release function of separating the transfer therefrom, it is preferable that a fluorine-based resin or a silicon-based resin having lower surface energy is added thereto so that the interlayer has a surface energy of 35mN/m or lower, more specifically, 18mN/m to 35mN/m, more preferably, 18mN/m to 25mN/m. In the case in which the surface energy is higher than 35mN/m, since the interlayer cannot perform the release function in the transfer process, the transfer layer is not separated therefrom, such that the transferring is not performed. Therefore, as the surface energy of the interlayer is lower, adhesive force between the transfer layer and the interlayer is decreased, such that the transferring may be smoothly performed in the transfer process. As the surface energy of the interlayer is higher, the adhesive strength between the transfer layer and the interlayer is increased, such that smooth transferring is difficult in the transfer process. A desirable range in performing the release function is 18mN/m to 35mN/m, more preferably, 18mN/m to 25mN/m, which is the range in which the transfer may be smoothly performed.

In addition, the interlayer of the present invention has an excellent form following capability in the case in which a portion of the transfer layer is transferred by a laser. In order to implement the characteristics as described above, the interlayer is characterized by having pencil hardness of H or lower.

In addition, preferably, the coated thickness after drying of the interlayer is 1.0 to 3.5㎛. In the case in which the thickness is less than 1.0㎛, heat shielding effect may be decreased to burn the transfer layer, and uniform surface shape may not be obtained, such that the surface of the transferred layer is not uniform, thereby decreasing resolution of the display. In the case in which the thickness is over 3.5㎛, the heat is excessively shielded, such that the transfer layer may not be transferred.

More specifically, in the case in which the surface roughness of the light-to-heat conversion layer is increased, the thickness of the interlayer needs to be increased in order to secure the uniform surface shape. In the case in which the surface roughness (Ra) value of the light-to-heat conversion layer is 10nm to 20nm, the thickness of the interlayer is 2.5 to 3.5㎛, in the case in which the surface roughness (Ra) value of the light-to-heat conversion layer is 5 to 10nm, the thickness of the interlayer is 2 to 3.5㎛, and in the case in which a surface roughness (Ra) value of the light-to-heat conversion layer is 5 nm or less, the thickness of the interlayer is 1 to 3㎛.

As the UV curable resin usable in the interlayer, urethaneacrylate, epoxy acrylate, polyester, acrylate, siliconacrylate, or the like, may be used. In order to control the surface roughness to be 35mN/m or less, a substituent including fluorine is grafted to a backbone of the UV curable resin, or a reactive or a nonreactive fluorine based and silicone based additives may be added as an additive. In addition, various additives may be added to the interlayer in order to remove static electricity.

Further, the hardness of the UV curable resin may be lowered by mixing with the thermoplastic resin in order to improve the form following capability. As an example of the thermoplastic resin, polyurethane resin, acrylate based resin, a polyester resin, a urethaneacrylate copolymer resin may be used. Preferably, the thermoplastic resin needs to have compatibility with the UV curable resin, and have glass transition temperature in the range of 50 to 110℃. It is preferable that the UV curable resin and the thermoplastic resin are mixed at a weight ratio of 70:30 to 99:1. In the case in which the content of the thermoplastic resin is over 30wt%, film flexibility is rather increased to decrease film strength, and thus, the transfer layer may be transferred together in the LITI process.

In addition, in order to lower the surface energy of the UV curable resin, the fluorine based additive and the silicone based additive may be further added thereto, as needed.

A specific example of the fluorine based additive may include a fluorine based compound having a vinyl reaction group, and a non-reactive fluorine-based additive, and the like. An example of the silicone-based additive may include polyether modified polydimethyl siloxane, a polyether modified dimethylpolysiloxane copolymer, a dimethylpolysiloxane based additive and a modified dimethylpolysiloxane based additive, a methylalkylsiloxane based additive, a siliconacrylate additive having reactivity, or the like. A specific example thereof may include BYK-300, BYK-301, and BYK-302 (BYK, Co., Ltd.,), Teramer USO-100 AMTE Co., Ltd) for product names, which is not limited thereto. Preferably, the additive has a content of 1 to 10 parts by weight based on 100 parts by weight of the UV curable resin.

In addition, an initiator may be used in an amount of 0.1 to 10 parts by weight based on 100 parts by weight of the UV curable resin. Any photopolymerization initiator may be used as the initiator without limitation, and specific examples thereof may include IRGACURE 184 and the like.

The interlayer may be formed by bar coating, roll coating, die coating, or the like.

In addition, the interlayer may be formed in a two layered-structure, and a aluminum deposition layer may be further formed on the interlayer, as needed.

Transfer Layer

The transfer layer is formed on the interlayer by being uniformly coated on the inter layer through evaporation, sputtering, solution-coating, or the like. The transfer layer generally includes at least one layer to be transferred to a receptor. For example, the transfer layer may be formed of an organic, inorganic, or organometallic material including an electroluminescent material or an electrically activate material, and other materials.

More specifically, an example of the materials may include poly(phenylenevinylene), poly-para-phenylene, polyfluorene, polydialkylfluorene, polythiophene, poly(9-vinylcarbazole), poly(N-vinylcarbazole-vinylalcohol)copolymer, triarylamine, polynorbornene, polyaniline, polyarylpolyamine, triphenylamine-polyetherketone, or the like, which is not limited thereto.

The transfer layer may further include one or more materials selected from a light emitting material, a hole transmissive organic material, and an electron transmissive organic material, known to the art, correspondingly characteristics of organic light emitting devices, and further include a compound including at least one selected from a non-light emitting low molecular material, a non-light emitting charge transfer polymer material, and a curable organic binder material.

A configuration of the transfer layer may be used without limitation as far as the configuration is generally used in the art.

In addition, the transfer layer may be formed in a two-layer structure including an aluminum deposition layer in order to improve releasing property.

While this invention has been described in connection with what is presently considered to be practical exemplary embodiments, it is to be understood that the invention is not limited to the disclosed embodiments, but, on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope of the appended claims.

Hereinafter, a method of measuring each physical property will be described below.

1) Surface Roughness

Surface roughness was measured by using a two-dimensional surface roughness measuring instrument (Kousaka Lab. Surfcorder SE-3300) under conditions that a radium of a stylus is 1㎛, a load is 0.7 mN, and a cutoff value is 80 ㎛. A portion in which standard length is 1.5mm from a curve of cross-section of a film in a center line direction thereof was selected. This process was repeated five times, and then calculate an average thereof. When Roughness curve is y=f(x) wherein the center line is X axis, and a vertical direction is y axis, the surface roughness was calculated by the following equation.

Surface Roughness (Ra)= (1/L)∫f(x)dx

2) Surface Energy

Surface energy was measured by a contact angle measuring instrument and purified water and diiodomethane were used to measure a contact angle. Then, the surface energy was obtained by Owens-Wendt method. The method as described above was repeated 10 times, and an average value thereof was then taken.

3) Transfer Property

Tris(8-hydroxyquinolinato)aluminium(Alq3) as a transfer layer was 500Åcoated on an inter layer, and transferring was then performed using a Nd YAG laser having 1064nm wavelength at an energy range of 100 to 130W.

When the transferred appearance after transferring is the same as a portion irradiated by the laser; O

When the transferred appearance after transferring is partially same as a portion irradiated by the laser; △

When the transferring is not performed in a portion irradiated by the laser; X

4) Blocking Property

10 prepared samples were overlapped, pressed by a load of 200gf/㎠, and then were left in 40℃ oven for 3 days, thereby determining whether or not the blocking was generated.

- Blocking is generated; X

- blocking is partially generated; △

- blocking is not generated; O

5) Form Following Capability

Tris(8-hydroxyquinolinato)aluminium(Alq3) as a transfer layer was 500Åcoated on an inter layer, and transferring was then performed using a Nd YAG laser having 1064nm wavelength at an energy range of 100 to 130W. A transferring width was 10㎛, and a depth of an acceptor was 0.2㎛.

An acceptor shape is clearly shown in the transferred shape after transferring; O

The acceptor shape is not shown in the transferred shape after transferring; X

6) Measurement of Pencil Hardness

A coating layer was formed on a PET substrate of 100㎛, to have a coated thickness after drying and UV curing of 5㎛. As described above, the pencil hardness was measured by a JIS K5400 method.

Example 1

Preparation of Composition (A-1) for forming light-to-heat conversion layer

Polyvinylchloridevinylacetate copolymer (Dow chemical Co., Ltd., VMCH grade) 18wt%, a polyurethane resin (Lubrizol Co., Ltd., ESTANE 5715 grade) 43wt%, polyisocyanate (Aekyung Chemical Co., Ltd., AK75 grade) 9wt%, and carbonblack (Degussa, PRINTEX L6 grade) 30wt% were added to a mixed solvent obtained by mixing toluene, methylethylketone, and cyclohexanone at a weight ratio of 1:1:1, so that the solid content became 15wt%, thereby preparing a composition for forming a light-to-heat conversion layer.

Here, a crude liquid was prepared through a kneading process and a milling filtering process as follows.

First, for the kneading process, the polyvinylchloridevinylacetate copolymer was warm-dissolved in the mixed solvent obtained by mixing toluene, methylethylketone, and cyclohexanone at a weight ratio of 1:1:1 at 50℃, thereby preparing 13wt% of a polyvinylchloride vinylacetate solution. After putting a predetermined amount of carbonblack into a kneading machine, a small amount of polyvinylchloridevinylacetate solution was put thereinto while operating the kneading machine, and then kneading was performed for 1 hour.

After completion of the kneading, the kneaded solution was put into a main milling container of a ring mill of which 80% is filled with 1.2mm zirconium particles. 20wt% polyurethane resin warm-dissolved at 50℃ by using the mixed solvent previously prepared by mixing toluene, methylethylketone, and cyclohexanone at a weight ratio of 1:1:1 and a mixture resin (weight ratio of toluene: methylethylketone: cyclohexanone = 1: 1: 1) were added thereinto, thereby preparing the solution having a solid content ratio of 15wt%. After putting of the prepared solution, two agitators in the milling machine were operated to perform the milling. One agitator used in order to put a mixed coating solution into the milling machine was set to be 1000 rpm, the other agitator mounted at a ring part for a particle distribution function was set to be 2000 rpm, and the agitators were operated for 6 hours.

The milled solution was filtered using a filter capable of filtering out particles of 2.5㎛ or larger. The filtered solution was coated using a mayer bar #8, and dried at 120℃ for 30 seconds. Then, in the case in which it was confirmed that a surface state does not have the particles of 2.5㎛ or larger through a microscope, the filtering was completed. After the filtering, polyisocyanate as a curing agent was put thereinto, and agitation was performed for 1 hour to prepare a composition for forming a light-to-heat conversion layer.

Preparation of Composition (B-1) for forming interlayer

A silicon based additive (BYK Co., Ltd., BYK-302) of 0.2wt% based on the entire composition was added to a UV curable urethaneacrylate resin (Toyo ink Co., Ltd., Lioduras LCH), preparing a composition for forming an interlayer.

Preparation of LITI donor film

A polyethyleneterephthalate (PET) film (Kolon industries, Inc., H11F) in which both surfaces thereof were treated by acrylprimer was prepared as a base film.

Composition (A-1) for forming the light-to-heat conversion layer was coated on an acryl primer layer of the prepared base film by a micro gravure coating method and then dried, thereby forming the light-to-heat conversion layer. In this case, a coated amount after drying was 1.5g/㎡. An aging process was further performed at 50℃ for 3 days.

Composition (B-1) for forming the interlayer, which was prepared, was coated on the light-to-heat conversion layer by using a microgravure coater and then dried, thereby forming the interlayer. In this case, the coated thickness thereof was controlled to be 2.0㎛.

Physical properties of the prepared film were measured, and the measurement results are shown in Table 1 below.

Example 2

A film was prepared by the same method as Example 1, except that the thickness of the interlayer was controlled to be 3.0㎛.

Example 3

A film was prepared by the same method as Example 1, except that the coated amount after drying of the light-to-heat conversion layer was controlled to be 2.5g/m².

Example 4

A film was prepared by the same method as Example 1, except that the composition of the light-to-heat conversion layer was changed.

Preparation of Composition (A-2) for forming light-to-heat conversion layer

Polyvinylchloridevinylacetate copolymer (Dow chemical Co., Ltd., VMCH grade) 16wt%, a polyurethane resin (Lubrizol, ESTANE 5715 grade) 37wt%, polyisocyanate (Aekyung Chemical Co., Ltd., AK75 grade) 7wt%, and carbonblack (Degussa, PRINTEX L6 grade) 40wt% were added to a mixed solvent obtained by mixing toluene, methylethylketone, and cyclohexanone at a weight ratio of 1:1:1, so that the solid content became 15wt%, thereby preparing a composition for forming a light-to-heat conversion layer.

Example 5

Preparation of Composition (A-3) for forming light-to-heat conversion layer

Polyvinylchloridevinylacetate copolymer (Dow chemical Co., Ltd., VMCH grade) 20wt%, a polyurethane resin (Lubrizol, ESTANE 5715 grade) 46wt%, polyisocyanate (Aekyung Chemical Co., Ltd., AK75 grade) 9wt%, and carbonblack (Degussa, PRINTEX L6 grade) 25wt% were added to a mixed solvent obtained by mixing toluene, methylethylketone, and cyclohexanone at a weight ratio of 1:1:1, so that the solid content became 15wt%, thereby preparing a composition for forming a light-to-heat conversion layer.

Example 6

A film was prepared by the same method as Example 1, except that the composition of the interlayer was changed.

Preparation of Composition (B-2) for forming interlayer

With respect to 100 parts by weight of the solid content of a fluorine substituted UV curable urethaneacrylate resin (Negami Co., Ltd., KY11M-45CF), 3 parts by weight of an initiator (Ciba Co., Ltd., Irgacure 184) was added to prepare the composition for forming the interlayer.

Example 7

Preparation of Composition (B-3) for forming interlayer

With respect to 100 parts by weight of the solid content of a UV curable urethaneacrylate resin (Negami Co., Ltd., KY11M-45CF), 3 parts by weight of an photoinitiator (Ciba Co., Ltd., Irgacure 184) and 3 parts by weight of a silicon-based additive (AMTE Co., Ltd., USO-100) were added to prepare the composition for forming the interlayer.

Example 8

Preparation of Composition (B-4) for forming interlayer

Example 9

Preparation of Composition (A-4) for forming light-to-heat conversion layer

Polyvinylchloridevinylacetate copolymer (Dow chemical Co., Ltd., VMCH grade) 18wt%, a polyurethane resin (Lubrizol Co., Ltd., ESTANE 5715 grade) 43wt%, polyisocyanate (Aekyung Chemical Co., Ltd., AK75 grade) 9wt%, carbonblack (Degussa, PRINTEX L6 grade) 30wt% were added to a mixed solvent obtained by mixing toluene, methylethylketone, and cyclohexanone by 1:1:1 weight ratio so as to have solid contents of 15wt%, thereby preparing a composition for producing a light-to-heat conversion layer.

First, for the kneading process, the polyvinylchloridevinylacetate copolymer was warm-dissolved in the mixed solvent obtained by mixing toluene, methylethylketone, and cyclohexanone at a weight ratio of 1:1:1 at 50℃, thereby preparing 13wt% of a polyvinylchloridevinylacetate solution. After putting a predetermined amount of carbonblack into a kneading machine, a small amount of polyvinylchloridevinylacetate solution was put thereinto while operating the kneading machine, and then kneading was performed for 1 hour.

The milled solution was filtered using a filter capable of filtering out particles of 3.0㎛ or larger. The filtered solution was coated using a mayer bar #8, and dried at 120℃ for 30 seconds. Then, in the case in which it was confirmed that a surface state does not have the particles of 3.0㎛ or larger through a microscope, the filtering was completed. After the filtering, polyisocyanate as a curing agent was put thereinto, and agitation was performed for 1 hour to prepare a composition for forming a light-to-heat conversion layer.

Example 10

A film was prepared by the same method as Example 1, except that the coated amount after drying of the light-to-heat conversion layer was controlled to be 3.5g/㎡.

Example 11

A film was prepared by the same method as Example 1, except that the thickness of the interlayer was controlled to be 3.5㎛.

Example 12

A film was prepared by the same method as Example 1, except that the thickness of the interlayer was controlled to be 4.0㎛.

Example 13

A film was prepared by the same method as Example 1, except that the thickness of the interlayer was controlled to be 0.5㎛.

Example 14

A film was prepared by the same method as Example 1, except that the coated amount after drying of the light-to-heat conversion layer was controlled to be 4.0g/㎡.

Example 15

A film was prepared by the same method as Example 1, except that the coated amount after drying of the light-to-heat conversion layer was controlled to be 0.5g/㎡.

Example 16

Preparation of composition (A-5) for forming light-to-heat conversion layer

Polyvinylchloridevinylacetate copolymer (Dow chemical Co., Ltd., VMCH grade) 43wt%, a polyurethane resin (Lubrizol Co., Ltd., ESTANE 5715 grade) 18wt%, polyisocyanate (Aekyung Chemical Co., Ltd., AK75 grade) 9wt%, carbonblack (Degussa, PRINTEX L6 grade) 30wt% were added to a mixed solvent obtained by mixing toluene, methylethylketone, and cyclohexanone at a weight ratio of 1:1:1 so as to have solid contents of 15wt%, thereby preparing a composition for producing a light-to-heat conversion layer.

Example 17

Preparation of composition (A-6) for forming light-to-heat conversion layer

Polyvinylchloridevinylacetate copolymer (Dow chemical Co., Ltd., VMCH grade) 12wt%, a polyurethane resin (Lubrizol, ESTANE 5715 grade) 30wt%, polyisocyanate (Aekyung Chemical Co., Ltd., AK75 grade) 8wt%, and carbonblack (Degussa, PRINTEX L6 grade) 50wt% were added to a mixed solvent obtained by mixing toluene, methylethylketone, and cyclohexanone at a weight ratio of 1:1:1, so that the solid content became 15wt%, thereby preparing a composition for forming a light-to-heat conversion layer.

Comparative Example 1

A film was prepared by the same method as Example 1, except that, PET film which is not primer-treated was used.

Comparative Example 2

A film was prepared by the same method as Example 1, except that the compositions of the interlayer and the light-to-heat conversion layer were changed.

Preparation of Composition (A-7) for forming light-to-heat conversion layer

Polyvinylchloridevinylacetate copolymer (Dow chemical Co., Ltd., VMCH grade) 12wt%, a polyurethane resin (Lubrizol, ESTANE 5715 grade) 30wt%, polyisocyanate (Aekyung Chemical Co., Ltd., AK75 grade) 8wt%, and carbonblack (Degussa, PRINTEX L6 grade) 80wt% were added to a mixed solvent obtained by mixing toluene, methylethylketone, and cyclohexanone at a weight ratio of 1:1:1, so that the solid content became 15wt%, thereby preparing a composition for forming a light-to-heat conversion layer.

Preparation of Composition (B-5) for forming interlayer

UV curable urethaneacrylate resin (Toyo ink Co., Ltd., Lioduras LCH series) was used. After the resin is diluted with methylethylketone solution to prepare a solution having solid content of 20wt%, a coating is performed.

[Table 1]

As shown in Table 1 above, it may be appreciated that the form following capability, the pencil hardness, the transfer property and the blocking property were excellent in the examples 1 to 11 in which the surface energy was 35mN/m or less, the thickness of the interlayer was 3.5㎛ or less, the coated amount after drying of the light-to-heat conversion layer was 3.5g/㎡ or less, and the carbon content was 40wt% or less.

In addition, it may be appreciated that in the comparative example 1 in which the primer layer was not formed, the form following capability and the transfer property was poor; and in the comparative example 2, the carbon content was high and surface energy was not controllable, such that the form following capability and the transfer property were poor and the blocking property was bad.

Example 18

Preparation of Composition (A-8) for forming light-to-heat conversion layer

After completion of the kneading, the kneaded solution was put into a main milling container of a ring mill of which 80% is filled with 1.2mm zirconium particles. 20wt% polyurethane resin warm-dissolved at 50℃ by using the mixed solvent previously prepared by mixing toluene, methylethylketone, and cyclohexanone at a weight ratio of 1:1:1 and a mixture resin (weight ratio of toluene: methylethylketone: cyclohexanone = 1: 1: 1) were added thereinto, thereby preparing the solution having a solid content ratio of 15wt%. After putting into the prepared solution, two agitators in the milling machine were operated to perform the milling. One agitator used in order to put a mixed coating solution into the milling machine was set to be 1000 rpm, the other agitator mounted at a ring part for a particle distribution function was set to be 2000 rpm, and the agitators were operated for 6 hours.

The milled solution was filtered using a filter capable of filtering particles of 2.5㎛ or larger. The filtered solution was coated using a mayer bar #8, and dried at 120℃ for 30 seconds. Then, in the case in which it was confirmed that a surface state does not have the particles of 2.5㎛ or larger through a microscope, the filtering was completed. After the filtering, polyisocyanate as a curing agent was put thereinto, and agitation was performed for 1 hour to prepare a composition for forming a light-to-heat conversion layer.

Preparation of Composition (B-6) for forming interlayer

An initiator (BASF Co., Ltd., IRGACURE 184) was added to a UV curable urethaneacrylate resin (Negami Co., Ltd., KY11) in an amount of 3 parts by weight based on 100 parts by weight of urethaneacrylate solid content, and a reactive siliconacrylate based additive (AMTE CO., Ltd., Teramer USO-100, solid content 100% solution) was added in an amount of 3 parts by weight of the entire urethaneacrylate solid content, to thereby prepare the composition for forming the interlayer.

Preparation of LITI donor film

Composition (A-8) for forming the light-to-heat conversion layer was coated on an acryl primer layer of the prepared base film by a micro gravure coating method and then dried, thereby forming the light-to-heat conversion layer. In this case, the coated thickness thereof coating after drying was 2.5㎛. An aging process was further performed at 50℃ for 3 days.

Composition (B-6) for forming the interlayer, which was prepared, was coated on the light-to-heat conversion layer by using a microgravure coater and then dried, thereby forming the interlayer. In this case, the coated thickness thereof was controlled to be 2.5㎛.

Physical properties of the prepared film were measured, and the measurement results are shown in Table 2 below.

Example 19

A film was prepared by the same method as Example 18, except that the composition of the interlayer was changed.

Preparation of Composition (B-7) for forming interlayer

A thermosetting urethaneacrylate resin (Taisei Co., Ltd., 8UA-146) and a UV curable urethaneacrylate resin (Negami Co., Ltd., KY-11) were combined so that a ratio of solid contents is 30:70. An initiator (BASF Co., Ltd., IRGACURE 184) was added in an amount of 3 parts by weight based on 100 parts by weight of urethaneacrylate solid content, and a reactive siliconacrylate based additive (AMTE CO., Ltd., Teramer USO-100, solid content 100% solution) was added in an amount of 3 parts by weight of the entire urethaneacrylate solid content, to thereby prepare the composition for forming the interlayer.

Example 20

Preparation of Composition (B-8) for forming interlayer

Comparative Example 3

Preparation of Composition (B-9) for forming interlayer

An initiator (BASF Co., Ltd., IRGACURE 184) was added to a UV curable urethaneacrylate resin (Negami Co., Ltd., UN-906) in an amount of 3 parts by weight urethaneacrylate solid content, and a reactive siliconacrylate based additive (AMTE CO., Ltd., Teramer USO-100, solid content 100% solution) was added in an amount of 3 parts by weight of the entire urethaneacrylate solid content, to thereby prepare the composition for forming the interlayer.

Comparative Example 4

Preparation of Composition (B-10) for forming interlayer

An initiator (BASF Co., Ltd., IRGACURE 184) was added to a UV curable urethaneacrylate resin (Negami Co., Ltd., UN908) in an amount of 3 parts by weight urethaneacrylate solid content, and a reactive siliconacrylate based additive (AMTE CO., Ltd., Teramer USO-100, solid content 100% solution) was added in an amount of 3 parts by weight of the entire urethaneacrylate solid content, to thereby prepare the composition for forming the interlayer.

[Table 2]

As shown in Table above, it may be appreciated that, in the LITI donor film according to the present invention, the pencil hardness in the interlayer was H or lower, such that the LITI donor film has excellent coating appearance and excellent transfer property when the LITI donor film is applied to laser transferring.

However, it may be appreciated that Comparative Examples 3 and 4 in which the pencil hardness of the interlayer was high had bad form following capability.

Therefore, it may be appreciated that the pencil hardness of the interlayer has an influence on the form following capability, and preferably, it has excellent form following capability when the pencil hardness thereof is in the range of 1H or lower.

Claims

A laser induced thermal imaging (LITI) donor film comprising: a base film, a primer layer, a light-to-heat conversion layer, an interlayer, and a transfer layer,

wherein the light-to-heat conversion layer includes a resin composition including a thermosetting resin and a light-to-heat conversion material, and the interlayer includes a UV curable resin and has a surface energy of 35mN/m or less.
The LITI donor film of claim 1, wherein the interlayer has a surface energy of 18mN/m to 35mN/m.
The LITI donor film of claim 2, wherein the interlayer has a surface energy of 18mN/m to 25mN/m.
The LITI donor film of claim 1, wherein the light-to-heat conversion layer has a surface-roughness (Ra) of 20nm or less.
The LITI donor film of claim 1, wherein in the light-to-heat conversion layer, the thermosetting resin is a polyurethane based resin and the light-to-heat conversion material is carbon-black.
The LITI donor film of claim 5, wherein the polyurethane based resin is selected from polyesterpolyurethane and polycarbonatepolyurethane.
The LITI donor film of claim 1, wherein the light-to-heat conversion material is included in an amount of 20 to 40 wt%.
The LITI donor film of claim 1, wherein the light-to-heat conversion material is dispersed in any one or two or more resins selected from polyvinylchloride, polyvinylchloride polyvinylacetate copolymer, and thermosetting polyurethane, and a solvent.
The LITI donor film of claim 1, wherein the light-to-heat conversion layer further includes a thermoplastic resin in an amount of no more than 50wt% based on the entire resin composition.
The LITI donor film of claim 1, wherein the light-to-heat conversion layer has a coated amount after drying of 1 to 3.5g/㎡.
The LITI donor film of claim 1, wherein the interlayer has a thickness of 1.0 to 3.5㎛.
The LITI donor film of claim 1, wherein the UV curable resin of the interlayer is a fluorine substituted UV curable resin.
The LITI donor film of claim 1, wherein the interlayer further includes a silicon-based resin or a fluorine-based resin.
The LITI donor film of claim 1, wherein the interlayer has a pencil hardness of H or lower, which is measured by JIS K5400.
A laser induced thermal imaging donor film, comprising: a base film, a primer layer, a light-to-heat conversion layer, an interlayer, and a transfer layer,

wherein the interlayer has a pencil hardness of H or lower, which is measured by JIS K5400.
The LITI donor film of claim 15, wherein the interlayer is obtained by coating and curing the UV curable resin composition.
The LITI donor film of claim 15, wherein the interlayer has a surface energy of 35mN/m.
The LITI donor film of claim 15, wherein the UV curable resin composition includes at least one UV curable resin selected from a group consisting of urethaneacrylate, epoxyacrylate, polyester acrylate and siliconacrylate, and an initiator.
The LITI donor film of claim 18, wherein the UV curable resin composition further includes at least one thermoplastic resin selected from a group consisting of a polyurethane resin, an acrylate based resin, a polyester resin, and urethaneacrylate copolymer.
The LITI donor film of claim 18, wherein the UV curable resin composition further includes a fluorine-based additive or a silicon-based additive.
A laser induced thermal imaging donor film, comprising: a base film, a primer layer, a light-to-heat conversion layer, an interlayer, and a transfer layer,

wherein the light-to-heat conversion layer includes a resin composition including a thermosetting resin and a light-to-heat conversion material, and the interlayer includes a UV curable resin and has a surface energy of 35mN/m or less, and a pencil hardness of H or lower, which is measured by JIS K5400.