KR20170116902A - Multilayer laser marking film and method for manufacturing the same - Google Patents

Abstract

An adhesive layer; A colored base layer having a first color; And a colored coating layer having a second color, wherein the first color and the second color are different colors, and the colored base layer comprises a urethane (meth) acrylate oligomer, a (meth) acrylate monomer; And a pigment; wherein the pressure sensitive adhesive layer comprises a first alkyl (meth) acrylate having a linear or branched alkyl group of 1 to 3 carbon atoms; Secondary alkyl (meth) acrylates having a linear or branched alkyl group of 4 to 16 carbon atoms; (Meth) acrylate having a carboxyl group and a copolymer resin of a mixed monomer component comprising a (meth) acrylate having a carboxyl group, and a process for producing the multilayer laser marking film.

Description

TECHNICAL FIELD [0001] The present invention relates to a multilayer laser marking film,

The present invention relates to a laser-markable multilayer film and a method of manufacturing the multilayer film.

Various articles have labels for their unique identification functions. These labels contain a variety of information about the item and also perform a unique identification function. For example, labels used in the automotive industry may be used to display information about various parts of a vehicle, such as, for example, tire pressure or fuel type, or to display unique security information, such as, for example, . In the event of theft or accident, these labels enable tracking of the vehicle.

As a kind of a method of manufacturing such a label, a method of writing information with a laser is used. For example, Korean Patent Laid-Open No. 10-2006-0027501 discloses an adhesive label sheet capable of marking a large amount of bar codes in a short time using a laser. And JP-A-1990-120042 discloses a heat-resistant display material having a marked layer on which an etching pattern is formed by a laser beam on a heat resistant base layer.

Such a label should have properties that can be precisely processed by a laser, have excellent adherence to an adherend, and realize various physical properties corresponding to the purpose and purpose at the same time. Therefore, research is needed to control the physical properties of the label according to each application and purpose.

One embodiment of the present invention provides a multi-layer laser marking film that is capable of precise punching and marking through a laser, and has physical properties that are easy to be desorbed and reattached within a short period of time after its attachment, and is excellent in reworkability. In addition, the multilayer laser marking film can exhibit excellent prevention performance for desorption, forgery, and modulation after a predetermined time has elapsed since the adhesion.

Another embodiment of the present invention is a method for producing a multilayer laser marking film having excellent physical properties as described above, and a method for manufacturing a multilayer laser marking film capable of realizing excellent durability of a multilayer structure of the film itself do.

In one embodiment of the present invention, an adhesive layer; A colored base layer having a first color; And a colored coating layer having a second color, wherein the first color and the second color are different colors, and the colored base layer comprises a urethane (meth) acrylate oligomer, a (meth) acrylate monomer; And a pigment; wherein the pressure sensitive adhesive layer comprises a first alkyl (meth) acrylate having a linear or branched alkyl group of 1 to 3 carbon atoms; Secondary alkyl (meth) acrylates having a linear or branched alkyl group of 4 to 16 carbon atoms; And a copolymerizable resin of a mixed monomer component comprising (meth) acrylate having a carboxyl group. The present invention also provides a multilayer laser marking film comprising a cured product of the pressure-sensitive adhesive composition.

In another embodiment of the present invention, a urethane (meth) acrylate oligomer, a (meth) acrylate monomer, And a pigment, and laminating another release film on top of the base composition; Curing the base composition to form a laminate in which a colored base layer having a first color is disposed between the two release films; Removing one release film from the laminate and forming a colored coating layer having a second color different from the first color on one side of the colored substrate layer; And a first alkyl (meth) acrylate having a linear or branched alkyl group having 1 to 3 carbon atoms on the other surface of the colored base layer after removing the other release film from the laminate; Secondary alkyl (meth) acrylates having a linear or branched alkyl group of 4 to 16 carbon atoms; And (c) forming a pressure-sensitive adhesive layer containing a cured product of a pressure-sensitive adhesive composition comprising a copolymer resin of a mixed monomer component containing a (meth) acrylate having a carboxyl group.

The multilayer laser marking film is capable of precise punching and marking with a laser, and has a property of easy detachability within a short period of time after attachment, thereby having excellent reworkability. In addition, the multilayer laser marking film can exhibit excellent prevention performance for desorption, forgery, and modulation after a predetermined time has elapsed since the adhesion.

The multilayer laser marking film can be produced with a high process efficiency. The multilayer laser marking film thus obtained has excellent interlayer interfacial adhesion, so that the multi-layer laser marking film has advantages of excellent durability Lt; / RTI >

1 schematically shows a cross section of a multilayer laser marking film according to an embodiment of the present invention.
Fig. 2 schematically shows a cross section of the multilayer laser marking film of Fig. 1 when laser marking is performed.
3 schematically shows a cross-section of a multilayer laser marking film according to another embodiment of the present invention.

BRIEF DESCRIPTION OF THE DRAWINGS The above and other features and advantages of the present invention will become more apparent by describing in detail exemplary embodiments thereof with reference to the attached drawings in which: These embodiments are provided so that this disclosure will be thorough and complete, and will fully convey the scope of the invention to those skilled in the art to which the invention pertains. Only. Like reference numerals refer to like elements throughout the specification.

In the drawings, the thickness is enlarged to clearly represent the layers and regions. In the drawings, for the convenience of explanation, the thicknesses of some layers and regions are exaggerated.

It will also be understood that when a layer, film, region, plate, or the like is referred to as being "on" or "over" another portion, . Conversely, when a part is "directly over" another part, it means that there is no other part in the middle. In addition, when a layer, film, region, plate, or the like is referred to as being "under" or "under" another portion, . Conversely, when a part is "directly underneath" another part, it means that there is no other part in the middle.

In one embodiment of the present invention, a multi-layer laser marking film comprising a pressure-sensitive adhesive layer, a colored base layer having a first color and a colored coating layer having a second color, wherein the first color and the second color are different colors, to provide.

 At this time, the colored base layer may contain urethane (meth) acrylate oligomer, (meth) acrylate monomer; And a pigment; wherein the pressure sensitive adhesive layer comprises a first alkyl (meth) acrylate having a linear or branched alkyl group of 1 to 3 carbon atoms; Secondary alkyl (meth) acrylates having a linear or branched alkyl group of 4 to 16 carbon atoms; And a copolymerizable resin of a mixed monomer component containing (meth) acrylate having a carboxyl group.

FIG. 1 schematically shows a multilayer laser marking film 100 according to an embodiment of the present invention, and specifically shows a cross section of the multilayer laser marking film 100 in detail.

1, the multilayer laser marking film 100 includes an adhesive layer 10, a colored base layer 20, and a colored coating layer 30. The multilayer laser marking film 100 includes, for example, Layer structure in which the colored substrate layer 20 is formed on the colored substrate layer 20 and the colored coating layer 30 is formed directly on the colored substrate layer 20.

The multilayer laser marking film is a film that can be etched by a laser and write various information. The 'laser marking' means writing information to the film by etching with a laser. Specifically, in the multilayer laser marking film, laser marking can be performed on the colored coating layer.

That is, the multilayer laser marking film has laser markability, and the laser markability refers to a property that the colored coating layer is etched by laser irradiation and the etched portion is removed. As described above, the laser-irradiated portion of the colored coating layer is etched and removed, thereby interacting with the colored substrate layer and writing various characters, drawings, and the like.

The colored substrate layer 20 and the colored coating layer 30 all have a color, and the term 'colored' means that the substrate layer or the coating layer is not transparent and has a color such as white, black, or blue . Specifically, the colored substrate layer 20 has a first color, the colored coating layer 30 has a second color, and the first color and the second color are different colors.

As described above, when the colored substrate layer and the colored coating layer have different colors from each other, when the colored coating layer is etched by laser marking, the etched portions can exhibit various colors depending on the etching depth.

Specifically, referring to FIG. 2A, only the first color of the colored substrate layer 20 can be visually recognized when the entirety of the colored coating layer 30 is etched by laser marking . Referring to FIG. 2B, when a part of the thickness of the colored coating layer 30 is etched, the first color of the colored substrate layer 20 and the color of the remaining colored coating layer 30 The color in which the second color appears superimposed can be visually recognized.

The multilayer laser marking film is capable of writing letters or patterns of various colors through laser marking. For example, the multilayer laser marking film can be used in automobiles and specifically displays information about various parts of the vehicle such as tire pressure or fuel type, unique security information such as vehicle identification number and vehicle identification number Lt; / RTI >

When the multilayer laser marking film according to an embodiment of the present invention is applied to a final position as described above, the multilayer laser marking film may be erroneously adhered to a position other than the intended position. In this case, It can have a possible advantage.

In addition, the multilayer laser marking film needs to prevent forgery or alteration of important information when it is written. Specifically, the multilayer laser marking film may have " fissile " property. The term " fracture property " means a property in which an original shape is destroyed and can not be recycled when an attempt is made to detach or remove the multilayer laser marking film after the multilayer laser marking film is attached to an adherend. Since the multilayer laser marking film has self-destructive properties, unique information written thereon can not be arbitrarily changed, and characteristics that can not be falsified or modulated can be secured.

The multilayer laser marking film can realize such properties and advantages by suitably controlling the composition and structure of the colored base layer and the adhesive layer.

Specifically, in the multi-layer laser marking film according to the embodiment of the present invention, the colored base layer may include a base material composition containing a (meth) acrylate oligomer and a (meth) acrylate-based monomer as a matrix constituting the colored base material layer Of the cured product.

The urethane (meth) acrylate oligomer is an oligomer having a urethane structure (-CONH-) in its chemical structure. It can be easily controlled in molecular weight as compared with an oligomer having another chemical structure, And it is advantageous to appropriately secure the interface adhesion force between the colored substrate layer and the upper and lower adhesive layers and the colored coating layer.

The urethane (meth) acrylate oligomer may have a weight average molecular weight (Mw) of from about 2,000 to about 10,000, for example, from about 2,000 to about 4,000. The above-mentioned urethane (meth) acrylate oligomer has a weight average molecular weight (Mw) in the above-mentioned range, whereby the cured product of the base composition can have an appropriate curing structure, and the colorant base layer, It is possible to ensure the appropriate interfacial adhesion of each of them. In addition, the colored base layer can greatly contribute to the improvement of the friability of the multilayer laser marking film, and the base matrix of the colored base layer can be constituted to easily perform the role of realizing basic durability.

In addition, the urethane (meth) acrylate oligomer may be a trifunctional or hexagonal oligomer. That is, the urethane (meth) acrylate oligomer may contain 3 to 6 (meth) acrylate groups in one molecule.

In one embodiment, the urethane (meth) acrylate oligomer is a trifunctional to tetrafunctional oligomer; Oligomers of five or six functionalities; Or a mixture of both. The trifunctional to tetrafunctional oligomers may be cured with the (meth) acrylate monomer to give excellent fracture properties, and the oligomer having five to six functional groups may undergo curing reaction in the oligomer itself, It is possible to give a sex.

The base composition comprises a (meth) acrylate monomer together with the urethane (meth) acrylate oligomer.

Specifically, the (meth) acrylate monomer may be a cyclo-aliphatic (meth) acrylate monomer, an epoxy (meth) acrylate monomer, an aliphatic (meth) Polyol-based (meth) acrylate monomers, and combinations thereof.

The monomer can interact with the urethane (meth) acrylate oligomer by including a (meth) acrylate monomer having the chemical structure of the above-described kind, thereby greatly improving the friability of the multilayer laser marking film.

Also, the weight average molecular weight (Mw) of the (meth) acrylate monomer may be from about 200 to about 500, for example from about 200 to about 300, for example from about 300 to about 400 . When the weight average molecular weight of the (meth) acrylate monomer satisfies the above-mentioned range, it can be properly crosslinked through the curing reaction between the oligomers serving as a matrix, resulting in a dense, hard, Coating layer can be realized.

The oligomer and the monomer of the base composition each have a weight-average molecular weight (Mw) of the same range as described above, and thus have a dense structure with high curing density and can be expected to have excellent reliability and accordingly have high tensile strength and appropriate elongation It is possible to realize excellent fracture and workability.

The (meth) acrylate monomer may be a bifunctional or higher functional monomer, for example, a bifunctional to tetrafunctional monomer. That is, the (meth) acrylate monomer may have two or more photoreactive functional groups in one molecule, for example, two to four. In addition, the photoreactive functional group may be a (meth) acrylate group.

Specifically, the cyclo-aliphatic (meth) acrylate monomer includes an alicyclic group in the chemical structure. For example, the cyclo-aliphatic (meth) acrylate monomer includes a cycloalkyl group having 3 to 25 carbon atoms and a heterocycloalkyl group having 2 to 25 carbon atoms And at least one selected from the group consisting of More specifically, the cyclo-aliphatic (meth) acrylate monomers may include one selected from the group consisting of cyclohexanedimethanol diacrylate, tricyclodecane dimethanol diacrylate, and combinations thereof. have.

The epoxy (meth) acrylate monomer may be selected from the group consisting of novolac type epoxy (meth) acrylate, bisphenol-A type epoxy (meth) acrylate, bisphenol-S type epoxy (Meth) acrylate of bisphenol-F type, epoxy (meth) acrylate of phenol type, epoxy (meth) acrylate of cresol novolak type, and combinations thereof.

The aliphatic (meth) acrylate monomer may be a compound having a (meth) acrylate group at each end of a main chain composed of alkylene structural units having 1 to 16 carbon atoms. More specifically, the aliphatic (meth) acrylate monomers are selected from the group consisting of 1,6-hexanediol di (meth) acrylate, 1,3-butanediol di (meth) acrylate, 1,4-butanediol di ) Acrylate, and combinations thereof.

The polyol (meth) acrylate monomer may be at least one selected from the group consisting of 1,6-hexanediol (ethoxylate) diacrylate, tripropylene glycol diacrylate, dipropylene glycol diacrylate, triethylene glycol diacrylate, Glycol diacrylate, and combinations thereof.

The multilayer laser marking film is remarkably excellent in fracture resistance. In addition, the interface between the colored base layer and the colored coating layer has an interface adhesion suitable for allowing the colored coating layer to be removed from the colored base layer by laser marking to enable the writing of fine width characters and patterns. In addition, the interface between the colored base layer and the adhesive layer has an interface adhesion suitable for applying the multilayer laser marking film to the final article and firmly adhering to realize long-term durability.

The colored base layer is an intermediate layer which is in contact with both the colored coating layer and the adhesive layer, and its composition can be suitably controlled to realize the above-mentioned physical properties and advantages.

Specifically, the base material composition for forming the colored base layer contains the (meth) acrylate monomer in an amount of more than about 0 parts by weight and not more than about 66 parts by weight based on 100 parts by weight of the urethane (meth) acrylate oligomer For example, from about 25 to about 40 parts by weight. When the (meth) acrylate monomer is used in an amount within the above-mentioned range with respect to the oligomer, the effect of improving the fracture property of the colored base layer is further improved, and the composition is cured to have appropriate hardness and elongation, Can be improved.

  The base composition comprises a pigment as a component for imparting color to the colored base layer. The kind of the pigment is not particularly limited, and various pigments may be used alone or in a suitable mixture according to the color of the colored base layer.

The pigment may be selected from, for example, titanium dioxide (TiO ₂ ), carbon black, platinum, azo pigments, cobalt violet, cadmium sulfide, chromic acid ferrocyanide, silicate, phosphate, phthalocyanine compound, (Dioxazine) compounds, and combinations thereof. However, the present invention is not limited thereto.

The base composition may include about 50 to about 135 parts by weight of the pigment, for example, about 80 to about 120 parts by weight, based on 100 parts by weight of the urethane (meth) acrylate oligomer. If the pigment is contained in an excessively small amount, the effect may be deteriorated in terms of the color contrast with the colored coating layer, and the friability may also be lowered. In addition, laser processing may not be performed properly. On the contrary, if the pigment is contained excessively, it may give a negative tendency to the curing process of the base composition, and it may hinder the colored base layer from securing proper interface adhesion and fracture property. Therefore, the pigment can be used in the above-mentioned range of contents to exhibit appropriate color without lowering the required physical properties of the colored base layer.

The colored base layer includes a cured product of the base composition, and the cured product may specifically be an electron beam cured product or an ultraviolet (UV) cured product. In the case of curing by heat or other curing means, since the curing proceeds slowly with a small energy, the crushability of the base layer is lowered and the elongation is too large, so that desired physical properties can not be realized. Therefore, since the colored base layer is made of an electron beam cured product or an ultraviolet ray cured product, a large amount of energy is instantaneously applied during curing, so that it is easy to secure the crushability.

1, the multilayer laser marking film 100 includes an adhesive layer 10 disposed on one side of the colored substrate layer 20, and the adhesive layer 10 is formed on the coloring substrate layer 20, And plays a role of improving the fracture property and reworkability together with the base layer.

Specifically, the adhesive layer may be a first alkyl (meth) acrylate having a linear or branched alkyl group having 1 to 3 carbon atoms; Secondary alkyl (meth) acrylates having a linear or branched alkyl group of 4 to 16 carbon atoms; And a copolymerizable resin of a mixed monomer component containing (meth) acrylate having a carboxyl group.

The copolymer resin of the pressure-sensitive adhesive composition may have a weight average molecular weight (Mw) of about 1,000,000 to about 150, for example, about 1,200,000 to about 130. By controlling the weight average molecular weight of the copolymer resin to the above range, the build-up process of the adhesive layer and the adherend can be performed at an appropriate speed, so that the multilayer laser marking film can realize improved reworkability have. In addition, the pressure-sensitive adhesive layer may be easy to implement appropriate friability together with the colored base layer.

 Specifically, the first alkyl (meth) acrylate has a linear or branched alkyl group having 1 to 3 carbon atoms and includes, for example, methyl (meth) acrylate, ethyl (meth) ) Acrylate, isopropyl (meth) acrylate, and combinations thereof.

The second alkyl (meth) acrylate has a linear or branched alkyl group having 4 to 16 carbon atoms, and examples thereof include n-butyl (meth) acrylate, isobutyl (meth) acrylate, Acrylate, isobutyl (meth) acrylate, hexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, heptyl (Meth) acrylate, isononyl (meth) acrylate, lauryl (meth) acrylate, tetradecyl (meth) acrylate and combinations thereof.

The (meth) acrylate having a carboxyl group may include one selected from the group consisting of acrylic acid, methacrylic acid, crotonic acid, itaconic acid, fumaric acid, cinnamic acid, and combinations thereof.

The mixed monomer component has a weight average molecular weight (Mw) in the above range by using the (meth) acrylate having the first alkyl (meth) acrylate, the second alkyl (meth) acrylate and the carboxyl group in an appropriate ratio, The adhesive layer can realize an appropriate interfacial adhesion force with the colored base layer due to the chemical structure derived from the respective monomers and the multilayer laser marking film can exhibit excellent friability and Excellent reworkability can be realized at the same time.

Specifically, the mixed monomer component may be prepared by mixing the first alkyl (meth) acrylate: the second alkyl (meth) acrylate: the carboxyl group-containing (meth) acrylate in a weight ratio of 20 to 30:60 to 70: 15 days.

The pressure-sensitive adhesive composition may further include a solvent and a curing agent together with the copolymer resin.

The type of the solvent is not particularly limited, but may include toluene. The pressure-sensitive adhesive composition can ensure an appropriate viscosity range through the solvent, and the coating property and workability can be improved.

The pressure-sensitive adhesive composition may have a viscosity of from about 1000 cps to about 5000 cps, for example from about 1500 cps to about 3000 cps, at room temperature from about 20 캜 to about 30 캜. By controlling the viscosity of the pressure-sensitive adhesive composition within the above range, excellent coatability and processability can be realized.

The curing agent may include one selected from the group consisting of an aziridine curing agent, a peroxide type curing agent, an isocyanate type curing agent, and combinations thereof. In one embodiment, the curing agent may comprise an aziridine curing agent. The adhesive composition may contain 0.01 to 1 part by weight of the curing agent relative to 100 parts by weight of the copolymer resin.

The multilayer laser marking film is used by attaching the adhesive layer so as to be in contact with an adherend. At this time, the multilayer laser marking film may have an adhesion force of about 1000 gf / inch or less after about 1 minute to about 10 minutes after the adhesive layer is adhered to an adherend of metal, for example, about 0 gf / inch , About 1000 gf / inch or less. As a result, the multilayer laser marking film can be detached again within a short time after attachment, and as a result, it can exhibit improved reworkability.

Referring to FIG. 1, the multilayer laser marking film 100 includes a colored coating layer 30 disposed on one side of the colored substrate layer 20. The colored coating layer 30 is a layer to be subjected to laser marking and is a layer which is etched by laser irradiation and is separated and removed from the colored base layer 20.

The colored coating layer 30 may include an ultraviolet (UV) cured product or an electron beam cured product of the coating composition, thereby realizing excellent reliability as compared with a case where the coloring coating layer 30 is produced by other curing means such as thermosetting.

Specifically, the coating composition comprises an ultraviolet curable oligomer or electron beam curable oligomer; And pigments.

The ultraviolet-curable oligomer or the electron-beam-curable oligomer may each include a bifunctional bisphenol A epoxy acrylate oligomer, a trifunctional urethane acrylate oligomer, or a mixture thereof.

The ultraviolet-curable oligomer or the electron-beam-curable oligomer may have a weight average molecular weight (Mw) of about 500 to about 3,000, for example, about 500 to about 2,000. Thus, the colored coating layer is excellent in durability and the precision of laser marking can be improved.

The colored coating layer has a color different from that of the colored base layer as described above. To the extent that the conditions with different colors are satisfied, the coating composition comprises a pigment.

For example, the pigment may be selected from the group consisting of titanium dioxide (TiO ₂ ), carbon black, stones, azo pigments, cobalt violet, cadmium sulfide, chromic acid ferrocyanide, silicate, phosphate, phthalocyanine But are not limited to, compounds selected from the group consisting of compounds, dioxazine compounds, and combinations thereof.

The colored substrate layer and the colored coating layer may contain different pigments to realize different colors. For example, the colored substrate layer may include white pigment including titanium dioxide (TiO ₂ ) as a pigment, and the colored coating layer may include black as a pigment including carbon black.

On the other hand, the colored base layer and the colored coating layer may contain different pigments and different colors may be realized by adjusting their contents.

The coating composition may contain about 1 to about 20 parts by weight of the pigment relative to 100 parts by weight of the ultraviolet-curable oligomer or electron beam-curable oligomer. As a result, the colored coating layer is easy to secure an appropriate adhesion with the colored base layer, and at the same time, a precise laser marking performance can be realized while exhibiting an appropriate color.

The multilayer laser marking film can realize improved crushibility by including the colored coating layer, the colored substrate layer and the adhesive layer together, and the interfacial adhesion between the respective layers is appropriately controlled, and the precision of laser marking and the durability Can be secured at the same time.

The multi-layer laser marking film is designed to appropriately design the thickness of the layer, thereby ensuring easy laser marking characteristics, realizing the fracture property, and securing the properties without breaking or tearing have.

The thickness of the colored coating layer may be, for example, from about 2 탆 to about 4 탆. By satisfying the thickness range of the colored coating layer, the efficiency of laser marking is improved, the colored coating layer etched from the colored base layer can be removed neatly, and the effect of visibility after laser marking can be easily realized .

Further, the thickness of the colored base layer may be, for example, about 50 탆 to about 150 탆. When the thickness of the colored base layer and the thickness of the colored coating layer satisfy the above range, the colored base layer can exhibit excellent durability during laser marking and can greatly contribute to improvement of the crushability of the multilayer laser marking film. The multi-layer laser marking film can be easily handled or handled, and the multilayer laser marking film can be excellent in puncture property when processed into a desired size.

Also, the thickness of the adhesive layer may be about 20 탆 to about 50 탆. When the thickness of the pressure-sensitive adhesive layer satisfies the above-described range, the multilayer laser-marking film can secure adhesion to the final product, and at the same time, the multilayer laser-marking film can smoothly function as an adhesive tape The effect can be obtained.

1, the multi-layer laser marking film 100 may include a multi-layer structure of an adhesive layer 10, a colored base layer 20, and a colored coating layer 30. As shown in FIG. Referring to FIG. 3, the multi-layer laser marking film 100 may further include a release layer 40 on one or both sides of the outermost edge.

3 (a), the release layer 40 may be formed on only one side of the adhesive layer 10, and the side of the adhesive layer 10 and the side of the colored coating layer 10 30 may be formed together.

The release layer 40 is removed when the multilayer laser marking film is applied to a final product. The release layer 40 formed on one side of the colored coating layer 30 may be removed before laser marking, It may be removed later. When the release layer 40 is removed after the laser marking, the release layer 40 may be formed of a material having transparency to the laser.

In another embodiment of the present invention, a method of producing the multilayer laser marking film is provided. The multilayer laser marking film is produced by preparing a colored base layer containing a cured product of the base composition and preparing a colored coating layer on one side of the colored base layer and an adhesive layer on the other side of the colored base layer .

Specifically, the multi-layer laser marking film may be formed by applying the base composition onto one release film and laminating another release film on the base composition; Curing the base composition to form a laminate in which a colored base layer having a first color is disposed between the two release films; Removing one release film from the laminate and forming a colored coating layer having a second color different from the first color on one side of the colored substrate layer; And removing the other release film from the laminate and forming an adhesive layer on the other surface of the colored substrate layer.

As described above, after the multilayer laser marking film has a structure in which a colored substrate layer is interposed between two release films, the two release films are sequentially removed, and then the both sides of the colored substrate layer By forming the above-mentioned colored coating layer and the above-mentioned pressure-sensitive adhesive layer on each other, the interfacial adhesion between the respective layers can be securely ensured. In addition, the thickness uniformity of the colored base layer can be improved.

Specifically, the colored coating layer is formed by applying the coating composition to one side of the colored substrate layer; And curing the coating composition to form a colored coating layer.

Alternatively, the colored coating layer may be prepared by preparing a transfer film comprising a cured product of the coating composition; And transferring the cured product of the coating composition onto the one side of the colored substrate layer through the transfer film to produce a colored coating layer.

The pressure-sensitive adhesive layer may be prepared by directly coating the pressure-sensitive adhesive composition on one side of the colored substrate layer and then thermally curing the pressure-sensitive adhesive composition. Alternatively, the adhesive layer may be prepared by previously preparing a pressure- Or the like.

At this time, the manufacturing method of the multilayer laser marking film may further include a step of corona treatment before forming the adhesive layer on one side of the colored substrate layer. That is, before the pressure-sensitive adhesive composition is directly coated, Or a corona treatment may be performed on one side of the colored substrate layer before the adhesive layer is laminated.

In one embodiment, the multilayer laser marking film is produced by corona treatment on one side of the colored substrate layer, followed by direct coating of the pressure sensitive adhesive composition onto the corona treated side, The pressure-sensitive adhesive layer can be produced. In this case, the adhesion between the colored base layer and the adhesive layer can be advantageously improved.

Hereinafter, specific embodiments of the present invention will be described. However, the embodiments described below are only intended to illustrate or explain the present invention, and thus the present invention should not be limited thereto.

< Manufacturing example >

Manufacturing example  1: Preparation of base composition

25 parts by weight of an alicyclic acrylate monomer having a weight average molecular weight (Mw) of 304 and 100 parts by weight of a trifunctional urethane acrylate oligomer having a weight average molecular weight (Mw) of 2,500 and 70 parts by weight of titanium dioxide (TiO ₂ ) Was prepared.

Manufacturing example  2-4: Preparation of adhesive composition

A pressure-sensitive adhesive composition comprising a copolymer resin and an aziridine curing agent as shown in Table 1 below was prepared. In Table 1, the content is expressed as parts by weight.

Adhesive composition Copolymer resin Aziridine hardener Composition ratio Mw content Kinds content Production Example 2 MA: EHA: AA = 25: 65: 10 125 million 100 Isophthaloylbis (2-Methylaziridine) 0.04 Production Example 3 MA: EHA: AA = 30: 65: 5 1.3 million 100 Isophthaloylbis (2-Methylaziridine) 0.04 Production Example 4 MA: EHA: AA = 25: 70: 5 1.1 million 100 Isophthaloylbis (2-Methylaziridine) 0.04 Production Example 5 GMA: EHA: AA = 25: 65: 10 1 million 100 Isophthaloylbis (2-Methylaziridine) 0.04 Production Example 6 GMA: BA: AA = 10: 80: 10 52 million 100 Isophthaloylbis (2-Methylaziridine) 0.04 Production Example 7 MA: HBA: AA = 25: 65: 10 34 million 100 Isophthaloylbis (2-Methylaziridine) 0.04

* MA: methyl acrylate

* EHA: Ethylhexyl acrylate

* AA: Acrylic acid

* GMA: glycidyl methacrylate

* BA: butyl acrylate

* HBA: hydroxybutyl acrylate

< Example  And Comparative Example >

Example  One

The base composition of Preparation Example 1 was applied to one surface of a polyethylene terephthalate (PET) release film, and the same PET release film was laminated on the surface.

Then, the base composition was cured by electron beam curing to prepare a laminate in which a release film, a colored base layer and a release film were laminated. Subsequently, one release film of the laminate was peeled off, and a trifunctional urethane acrylate oligomer (Mwaspo ™ o) having a weight average molecular weight (Mw) of 1900 as an ultraviolet-curable oligomer was laminated on one side of the colored substrate layer from which the release film was peeled 100 parts by weight of a mixture of a bifunctional bisphenol A epoxy acrylate oligomer (SARTOMER, CN120C80) manufactured by Mitsubishi Chemical Corporation, MIRAMER PU3200); And 5 parts by weight of carbon black was applied and then UV-cured to prepare a colored coating layer.

Then, another release film of the laminate was peeled off, the back surface of the colored base layer was corona-treated, the pressure-sensitive adhesive composition of Production Example 2 was applied, and then thermally cured at 110 DEG C for 3 minutes to form an adhesive layer .

Thus, a multilayer laser marking film including a colored coating layer having a thickness of 2 mu m, a colored base layer having a thickness of 100 mu m and a pressure-sensitive adhesive layer having a thickness of 25 mu m was produced.

Example  2

A multilayer laser marking film was produced in the same manner as in Example 1 except that the pressure-sensitive adhesive composition of Production Example 3 was used.

Example  3

A multilayer laser marking film was produced in the same manner as in Example 1, except that the pressure-sensitive adhesive composition of Production Example 4 was used.

Comparative Example  One

A multilayer laser marking film was produced in the same manner as in Example 1 except that the pressure-sensitive adhesive composition of Production Example 5 was used.

Comparative Example  2

A multilayer laser marking film was produced in the same manner as in Example 1 except that the pressure-sensitive adhesive composition of Production Example 6 was used.

Comparative Example  3

A multilayer laser marking film was produced in the same manner as in Example 1 except that the pressure-sensitive adhesive composition of Production Example 7 was used.

<Evaluation>

Experimental Example  1: Within a short time Reworkability  evaluation

Each of the multilayer laser marking films of Example 1-3 and Comparative Example 1-3 was produced with specimens having a size of 2.54 cm 10 cm (width x length), and then adhered to each of the adhesive layers on an aluminum- And the 2 kg roller is reciprocated 5 times so that the 2 cm end in the longitudinal direction is not attached. After a lapse of 10 minutes from the point of attachment, detachment is attempted from a portion not attached to the end in the longitudinal direction, and the detachability is observed. In addition, if it is detachable, it is observed whether or not it is attached again.

The results are shown in Table 2 below. Specifically, the case where the multilayer laser film can be detached and the case where the multilayer laser film can be reattached is referred to as 'OK', and the case where the multilayered laser film is not detached and the peeled residue is left as 'NG' is described.

Experimental Example  2: Friable  evaluation

For each of the multilayer laser marking films of Examples 1-3 and 1-3, a sample of 75 mm x 150 mm size was attached to a coating of aluminum and exposed to isopropyl alcohol (IPA) at a concentration of 100% After 1 hour, the fracture property was evaluated according to whether or not the shape was broken at the time of forced desorption using a knife. The results are shown in Table 2 below. 'OK' is described as a case of being broken at the time of desorption, and 'NG' is described as a case of being desorbed without being broken at the time of desorption.

Short-time reworkability Friability Desorption after 10 minutes Reattachment after desorption Example 1 OK OK OK Example 2 OK OK OK Example 3 OK OK OK Comparative Example 1 OK NG OK Comparative Example 2 NG NG OK Comparative Example 3 NG NG OK

With reference to Tables 1 and 2, the multilayer laser marking films of Examples 1 to 3 according to an embodiment of the present invention were obtained through the coloring substrate layer and the adhesive layer as described above, It can be seen that the short-time reprocessability and the fracture property are realized at the same time as compared with the multilayer laser marking film.

Specifically, in the case of Comparative Example 1, desorption can be performed within a short period of time after attachment, but it is impossible to reattach it, so that it can be seen that the required level of short-time reworkability can not be realized.

In addition, in the case of Comparative Examples 2 to 3, since desorption and reattachment within a short time after attachment can not be performed, it can be seen that the reworkability is significantly inferior to those of Examples 1 to 3.

100, 100 ': multilayer laser marking film
10: Adhesive layer
20: colored substrate layer
30: colored coating layer
40:

Claims (17)

An adhesive layer; A colored base layer having a first color; And a colored coating layer having a second color, wherein the first color and the second color are different colors from each other,
The colored substrate layer may comprise urethane (meth) acrylate oligomer; (Meth) acrylate monomers; And a cured product of a base composition comprising a pigment,
Wherein the adhesive layer comprises a first alkyl (meth) acrylate having a linear or branched alkyl group having 1 to 3 carbon atoms; Secondary alkyl (meth) acrylates having a linear or branched alkyl group of 4 to 16 carbon atoms; And a copolymerizable resin of a mixed monomer component comprising a (meth) acrylate having a carboxyl group
Multilayer laser marking film.
The method according to claim 1,
Wherein the colored coating layer is etched by laser irradiation and the etched portion is removed,
Multilayer laser marking film.
The method according to claim 1,
The weight average molecular weight (Mw) of the copolymer resin is from 1 million to 1.5 million
Multilayer laser marking film.
The method according to claim 1,
Wherein the mixed monomer component is a mixture of the first alkyl (meth) acrylate: second alkyl (meth) acrylate: carboxyl group-containing (meth) acrylate in a weight ratio of 20 to 30:60 to 70:
Multilayer laser marking film.
The method according to claim 1,
The weight average molecular weight (Mw) of the urethane (meth) acrylate oligomer is 2,000 to 10,000
Multilayer laser marking film.
The method according to claim 1,
The urethane (meth) acrylate oligomer is a trifunctional or hexafunctional
Multilayer laser marking film.
The method according to claim 1,
The weight average molecular weight (Mw) of the (meth) acrylate monomer is 200 to 500
Multilayer laser marking film.
The method according to claim 1,
The (meth) acrylate monomer may be a bifunctional to tetrafunctional
Multilayer laser marking film.
The method according to claim 1,
The (meth) acrylate monomer may be a cyclo-aliphatic (meth) acrylate monomer, an epoxy (meth) acrylate monomer, an aliphatic (meth) acrylate monomer, a polyol ) Based (meth) acrylate monomers, and combinations thereof.
Multilayer laser marking film.
The method according to claim 1,
The above-mentioned base composition is characterized by containing (meth) acrylate monomer in an amount of more than 0 parts by weight and not more than 66 parts by weight, based on 100 parts by weight of the urethane (meth) acrylate oligomer
Multilayer laser marking film.
The method according to claim 1,
The base composition comprises 50 to 135 parts by weight of the pigment, based on 100 parts by weight of the urethane (meth) acrylate oligomer
Multilayer laser marking film.
The method according to claim 1,
The adhesive force of 1 to 10 minutes after adhesion of the adhesive layer to the adherend of metal is 1000 gf / cm or less
Multilayer laser marking film.
The method according to claim 1,
The colored coating layer may comprise an ultraviolet curable oligomer or electron beam curable oligomer; And a cure of a coating composition comprising a pigment
Multilayer laser marking film.
14. The method of claim 13,
The ultraviolet-curable oligomer or electron-beam-curable oligomer may be at least one compound selected from the group consisting of bifunctional bisphenol A epoxy acrylate oligomers, trifunctional urethane acrylate oligomers,
Multilayer laser marking film.
A urethane (meth) acrylate oligomer, a (meth) acrylate monomer on the one release film; And a pigment, and laminating another release film on top of the base composition;
Curing the base composition to form a laminate in which a colored base layer having a first color is disposed between the two release films;
Removing one release film from the laminate and forming a colored coating layer having a second color different from the first color on one side of the colored substrate layer; And
A first alkyl (meth) acrylate having a linear or branched alkyl group having 1 to 3 carbon atoms on the other surface of the colored base layer after removing the other release film from the laminate; Secondary alkyl (meth) acrylates having a linear or branched alkyl group of 4 to 16 carbon atoms; (Meth) acrylate having a carboxyl group and a copolymer resin of a mixed monomer component comprising a (meth) acrylate having a carboxyl group
A method for producing a multilayer laser marking film.
16. The method of claim 15,
The step of forming the adhesive layer comprises:
Directly coating the pressure-sensitive adhesive composition on the other surface of the colored substrate layer, and curing the pressure-sensitive adhesive composition;
Forming a pressure-sensitive adhesive layer comprising a cured product of the pressure-sensitive adhesive composition on the other surface of the colored substrate layer;
A method for producing a multilayer laser marking film.
16. The method of claim 15,
The step of forming the adhesive layer comprises:
Further comprising the step of corona treating the other side of the colored substrate layer before forming the adhesive layer
A method for producing a multilayer laser marking film.

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