JP2009216749A - Fragile lamination label for laser printing - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fragile lamination label for laser printing, which satisfies characteristics as the label and hardly causes a fracture during stripping from release paper and during attaching operation. <P>SOLUTION: The fragile lamination label for laser printing with adhesive comprises a colored layer made of a crosslinked acrylic resin, a support layer, a breakage layer, an adhesive layer, and the release paper, and cannot be recycled. The label has a breakage angle at 10°C of 85 to 140° and stripping force of 150 mN/25.4 mm or less when being peeled from the release paper E. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

The present invention relates to a fragile laminated label for laser printing that performs printing with a laser beam. More specifically, the present invention relates to a laminating label for laser printing. The present invention relates to a brittle laminated label for laser printing that has good workability and cannot be reused after peeling once it has been applied.

For the purpose of product management and quality assurance, it is widely practiced to attach labels, sheets or the like on which individual information such as production numbers and expiration dates are printed to individual products.

As a printing method on the label sheet, for example, a method of printing liquid ink using a screen plate, a method of printing ink by thermal transfer using an ink ribbon, a method of printing ink using an ink jet printer, etc. are used. However, it is complicated and difficult to print different pieces of information individually on a large number of products by the above-described method.

Therefore, the surface layer and the base layer of the base material are provided with a concealing layer that absorbs laser light and can be removed by heat generation and destruction, and a base layer of a different color having a brightness difference that can be easily seen, and laser light is emitted from the surface. Laser printing laminates have been proposed that can perform desired printing of the color of the underlying layer by adjusting the output and irradiating a pattern such as characters so as to remove the concealing layer (Patent Documents 1 and 2). ).

These laser-printed labels with serial numbers etc. are also used for certification labels for machines and automobile parts, approval labels, etc., but if the place where the labels are used is in the engine room, etc., the operating temperature is 50 ° C. It may rise further.
In addition, even in automobiles that are used in the tropics and deserts, etc., authentication labels that are affixed to various places inside and outside the vehicle are exposed to intense direct sunlight or are exposed to harsh temperature environments. There are many.

When a normal laser-printed label is used under such severe temperature conditions, cracks and curls occur, and there is a problem that the label breaks without waiting for the service life of an automobile or the like.

Although an attempt was made to use a general label as a laser-printed laminate, the printability and handling properties were insufficient and could not be put to practical use.

In addition, a method of providing a heat-resistant resin such as a polyimide resin or a polyamide resin, which is generally used, as a layer for forming a laser printing label as a colored resin layer has been considered. Many of them are hard and brittle resin layers, which are not flexible enough to be used as labels to be attached to uneven curved surfaces, such as the surfaces of automobiles and motorcycles and the surface of machine parts. Such a problem occurred.

In Japanese Patent Application Laid-Open No. 2007-021818 (Patent Document 3), the present invention provides a laser-printable laminate comprising a colored resin layer, a colored breaking layer made of a crosslinked acrylic resin containing a glycol compound, and an adhesive layer. A laminate that can be attached to a curved surface and has brittleness has been proposed. However, since the laminate is soft and does not have an appropriate stiffness, there is a problem in that workability is poor when labeling and attaching to a substrate.

Therefore, the present inventors have intensively studied and applied a label to a substrate in Japanese Patent Application No. 2006-283051 (Patent Document 4: unpublished) and Japanese Patent Application No. 2006-283052 (Patent Document 5: unpublished). A brittle laminate for laser printing with improved pasting workability was proposed.

Many brittle laser labels manufactured from the laminate are continuously formed on release paper. Each brittle label on the release paper is printed with a serial number, etc. with a laser, and then peeled off from the release paper one by one so that it is not destroyed by the operator. Attached.

The laser labels disclosed in Patent Documents 5 and 6 may be broken or broken at the time of peeling work from the release paper if the operator is not skilled at the time of sticking work. There were inconveniences that the rate was high and production was delayed due to the re-take of failed labels.

Therefore, there has been a demand for a brittle laser label that satisfies the properties as a label and hardly causes damage during peeling from a release paper and during affixing operation.

JP 09-123606 A JP 09-123607 A JP 2007-021818 A Japanese Patent Application No. 2006-283051 Japanese Patent Application No. 2006-283052

The problem to be solved by the present invention is to provide a laser-printed laminate that can be clearly printed and that is less damaged during affixing operations.

The present inventors comprise the following (A) to (E): a fragile laminated label for fragile laser printing that cannot be reused due to destruction of the colored layer when peeled after being applied to a substrate. ,
The brittle laminate label for laser printing with adhesive (A) + (B) + (C) + (D) has a crack angle at 10 ° C. of 85 ° to 140 °, and is peeled off from the release paper (E). A brittle laminated label for brittle laser printing having a peeling force of 150 mN / 25.4 mm or less.
(A) A colored layer comprising a cross-linked acrylic resin and serving as the outermost layer when the laminate is attached to a substrate;
(B) a support layer comprising a cross-linked acrylic resin having a color difference visible to the colored layer (A) and laminated on the colored layer;
(C) a destructive layer laminated on the support layer (B),
(D) The pressure-sensitive adhesive layer (E) laminated on the breaking layer (C) The above problem was solved by the release paper laminated on the pressure-sensitive adhesive layer (D).

In the laminate of the present invention, the colored layer is destroyed and removed in a desired shape by laser light irradiation, so that the color of the support layer can be visually recognized in the removed portion, and laser printing that can express desired printing and images. It is a brittle laminated label.

The laminate of the present invention does not cause poor appearance such as cracks even when exposed to harsh temperature conditions for a long time, does not peel off, and can be applied following a curved surface, etc. It is a brittle laminated label for laser printing that is less broken when applied to a substrate, has good workability, and cannot be reused after peeling.

The laminated body of this invention is demonstrated in detail below.
The brittle laminate label of the present invention heats and melts the irradiated part by irradiating the colored layer with the ability to absorb laser light by adjusting the output of the laser light and condensing it into a pattern such as letters. A fragile laminated label for laser printing that is misted or exothermic / decomposed / ashed, removed in a pattern, and reveals the color of the support layer or fracture layer in the removed portion. Having different layers.

The brittle laminate label of the present invention has a colored layer on the surface that can be removed by laser light irradiation. The colored layer is formed by laminating or coating a colored resin obtained by adding a colorant to an acrylic resin on the support layer with a predetermined thickness by a known method.

The resin constituting the colored layer used in the present invention is preferably a crosslinked acrylic resin crosslinked with an amino resin crosslinking agent. The cross-linked acrylic resin herein is a resin obtained by cross-linking an acrylic resin having a functional group with a cross-linking agent or the like. An acrylic resin is a resin whose main component is a resin produced by polymerization of an acrylic monomer or a methacrylic monomer, and the main component means a resin containing 50% or more of an acrylic resin as a resin component.

Examples of the acrylic monomer include resins obtained by copolymerization using acrylic acid ester, methyl acrylate, propyl acrylate, butyl acrylate, 2-hydroxyethyl acrylate, 2-ethylhexyl acrylate, and the like as monomers, Examples of the methacrylic acid monomer include methyl methacrylate, ethyl methacrylate, propyl methacrylate, butyl methacrylate, and ethylene glycol dimethacrylate. Examples of the functional group include a hydroxyl group, a mercapto group, an epoxy group, an amide group, and a methylolated acrylamide group.

Among the resins, a resin obtained by copolymerizing a monomer having a hydroxyl group as a functional group is preferable from the viewpoint of controlling pot life after mixing with a crosslinking agent and tensile breaking elongation after crosslinking. In view of this, a resin copolymerized with methyl methacrylate (MMA) as a monomer is preferable.

Examples of the cross-linking agent for the colored layer of the present invention include melamine-based, guanamine-based, urea-based cross-linking agents, etc., but in consideration of physical properties such as heat resistance and control of tensile elongation at break after cross-linking, melamine-based cross-linking. Agents are preferred.
The crosslinking agent is used in an amount of 0.5 to 1.5 equivalents, preferably 0.8 to 1.2 equivalents, based on the reactive functional group of the resin.

The thickness of the colored layer is 10 to 30 μm, preferably 10 to 20 μm. If the thickness is 10 μm or more, sufficient concealability can be obtained, and if it is less than 30 μm, the irradiated portion can be completely removed by laser light irradiation.

The colorant content of the colored layer is preferably 1 to 300% by weight, preferably 5 to 250% by weight, more preferably 8 to 200% by weight. When the content of the colorant is less than 1% by weight, the concealability is generally low and it is difficult to provide contrast with the back surface. When the content of the colorant is 300% by weight or more, the colorant layer becomes too brittle. Cracks may occur.

The colorant used in the colored layer of the present invention and the support layer and destruction layer described below is not particularly limited, but it is a weatherable and durable colorant that can be removed by laser light irradiation and can be used for a long period of time. Specifically, it can be selected from colorants listed in Color Index 3rd Edition (1971) and Supplements (1975) published by The Society of Dyers and Colorists. The colorant names shown below are based on the Color Index Generic Name specified in the same document. For example, Bk-1 means CIPigment Black1, Bk represents black (Black), and W represents white (White).
As the color of the colorant, any color tone such as yellow, orange, red, purple, blue, green, brown, black and white can be used. Usually black or white is used. Specific examples of preferred colorants are given below.

Examples of the preferable black colorants include organic pigments and inorganic pigments. Examples of preferable organic pigments include aniline black (Bk-1) and perylene black (Bk-31). Can

Examples of inorganic pigments include carbon black (Bk-31), carbon black (Bk-7), carbon black (Bk-9), iron black (Bk-11), Examples thereof include cobalt oxide pigments (Bk-13).

Among them, a preferable pigment is carbon black (black) in the form of amorphous or graphite. The preferred average particle size of carbon black is in the range of 10 to 500 nm, particularly preferably in the range of 15 to 120 nm, and various commercially available carbon blacks having a fine average particle size can be used.

Further, as the preferred white pigment, inorganic pigments are preferable, for example, zinc white (W-4), zinc sulfide (W-7), titanium dioxide (W-6), calcium carbonate (W-18). , Clay (W-19), barium sulfate (W-21), alumina white (W-24), silica (W-27), muscovite (W-20), tank (W-26), etc. Can do.

Among them, a preferable pigment is rutile type titanium oxide (white). The preferable average particle diameter of titanium oxide is in the range of 10 to 500 nm, particularly preferably in the range of 20 to 100 nm, and various commercially available types of titanium oxide having a fine average particle diameter can be used.

Moreover, the said colored layer can contain a mica and aluminum powder in the range which does not affect the coloring property and a weather resistance other than the said coloring agent.

When carbon black or titanium oxide is used, the colorant can itself be a compound that converts laser light into heat. However, if the colorant is not absorptive with respect to the laser light, a compound for converting the laser light into heat may be required, in which case a mixture of colorants or one or more colorants And a mixture of one or more compounds capable of converting laser light into heat.

Examples of the compound for converting laser light into heat include carbon black, cyanine-based, phthalocyanine-based infrared absorbers, and the like.

The brittle laminated label of the present invention is laminated on the colored layer, has a color difference visible from the colored layer, and has a support layer made of a crosslinked acrylic resin. As the acrylic resin used for the support layer, the same resin as that used for the colored layer described above is used. However, the resin must be flexible with a tensile elongation at break of 15% or more. And additives are different from the colored layer.

As the crosslinking agent used for crosslinking the acrylic resin of the support layer, an isocyanate crosslinking agent is preferable, and an aliphatic isocyanate or an alicyclic isocyanate is particularly preferable in consideration of flexibility after crosslinking.
Specifically, for example, transcyclohexane 1,4-diisocyanate, pentamethylene diisocyanate, hexamethylene diisocyanate, heptamethylene diisocyanate, 4,4′-dicyclohexylbutane diisocyanate, lysine diisocyanate, isophorone diisocyanate, lysine ester triisocyanate, 1,6 , 11-undecatriisocyanate, 1,8-diisocyanate-4-isocyanate methyloctane, 1,3,6-hexamethylene triisocyanate, bicycloheptane triisocyanate, trimethylhexamethylene diisocyanate and the like.

The crosslinking agent is used in an amount of 0.1 to 1.3 equivalents, preferably 0.2 to 1.0 equivalents, relative to the functional group equivalent of the support layer resin. When the amount of the crosslinking agent is too large, flexibility is impaired, and when it is too small, heat resistance and durability are impaired.

Although the said support layer is colored in the color visually recognizable with a colored layer, the coloring agent which can be used for the colored layer mentioned above can be used similarly. The colorant content of the support layer is 10 to 500% by weight, preferably 30 to 300% by weight, more preferably 40 to 250% by weight. When the colorant content is 10% by weight or more, it is possible to ensure concealability, and when it is less than 500% by weight, it can be held as a film.

In order to maintain the flexibility of the support layer, a glycol compound can be used as a softening agent. The glycol compound is a condensed compound of diol, such as ethylene glycol, propylene glycol, 1,4-butanediol, diethylene glycol, etc., and polymers include polyethylene glycol, polytetramethyl glycol, THF-neopentyl glycol copolymer Polymer type glycol compounds are preferable from the viewpoint of volatility of glycol itself, degree of imparting flexibility per added amount, water resistance, and availability of polytetramethyl. Glycol is particularly preferred.

The glycol compound may be contained in an amount of 1 to 10% by weight, preferably 2 to 8% by weight, particularly preferably 3 to 6% by weight, based on the resin composition.
If the glycol compound is larger than 1% by weight, the film will not crack even if it is bent during application, and if it is less than 10% by weight, the film will not break and it will not be possible to peel off the label once attached. Therefore, it is preferable.

The thickness of the support layer is 30 to 60 μm, preferably 40 to 50 μm. If the thickness is 30 μm or more, sufficient flexibility can be imparted to the laminate, and if it is 60 μm or less, the fracture resistance during peeling can be imparted.

The brittle laminate label of the present invention is laminated on the support layer and has a fracture layer made of an acrylic resin. The breaking layer is preferably made of a cross-linked acrylic resin. As the acrylic resin, a resin similar to the resin used for the colored layer described above is used.
The fracture layer is formed of a resin imparted with brittleness by cross-linking or addition of a brittleness imparting component described later, and its tensile fracture elongation must be less than 10%.

Examples of the crosslinking agent used for crosslinking the acrylic resin of the destructive layer include a melamine crosslinking agent, an isocyanate crosslinking agent, an epoxy crosslinking agent, a polyamine crosslinking agent, and an aldehyde crosslinking agent. In consideration of physical properties such as control of hardness after crosslinking, a melamine-based crosslinking agent and an isocyanate-based crosslinking agent can be preferably used as long as the tensile elongation at break is satisfied.

The said melamine type crosslinking agent used for a colored layer and the said isocyanate type crosslinking agent used for a support layer can be suitably used in the range which satisfies the said tensile fracture elongation.

The crosslinking agent is used in an amount of 0.1 to 1.5 equivalents, preferably 0.2 to 1.3 equivalents, particularly preferably 0.3 to 1.2 equivalents, relative to the functional group equivalent of the fracture layer resin. If the amount of the crosslinking agent is too much, it becomes too brittle and the workability is impaired, and if it is too little, it becomes difficult to break.

It is also preferable to add a component imparting brittleness to the fracture layer.
As the component imparting brittleness, inorganic particles such as glass beads, silica and calcium carbonate, and organic particles such as acrylic beads, styrene beads and silicone beads can be used, but from the viewpoint of narrow particle size distribution. Glass beads, acrylic beads, styrene beads, and silicone beads are preferable, and glass beads and acrylic beads are particularly preferable in consideration of heat resistance.

When inorganic particles or organic particles are used as the brittleness imparting component, the average particle size needs to be not more than the thickness of the brittle layer, and is 1 to 150 μm, preferably 5 to 100 μm, particularly preferably 10 to 80 μm.
If the particle diameter is 1 μm or more, brittleness can be imparted, and if it is less than 150 μm, cracks during the pasting operation are difficult to occur.

The content of the brittleness imparting component is 0.5 to 10 parts by weight, preferably 0.8 to 7 parts by weight, and particularly preferably 1 to 5 parts by weight with respect to 100 parts by weight of the resin.
If the brittleness-imparting component is 0.5 parts by weight or more with respect to 100 parts by weight of the resin, there is an effect of imparting brittleness. Does not enter.

Further, the breaking layer may be colored or transparent, but when colored, it is preferably colored in the same hue as the support layer, and the colorant that can be used in the above-described colored layer is the same. Can be used. The content of the colorant in the destructive layer is 10 to 500% by weight, preferably 30 to 300% by weight, and more preferably 50 to 250% by weight. When the colorant content is 10% by weight or more, it is possible to ensure concealment, and when it is less than 500% by weight, it can be held as a film.

An adhesive layer is further laminated on the brittle laminate label of the patent invention. The adhesive layer has a thickness of 15 to 100 μm, preferably 20 to 70 μm, more preferably 25 to 45 μm. If the film thickness is 15 μm or more, adhesion to the adherend can be ensured, and if the film thickness is less than 100 μm, the adherability is good and the cost is advantageous.

Further, the adhesive strength of the adhesive layer was determined as 5N / 25.4 mm measured by a 180 ° folded peel test using a tensile tester after being bonded to an adherend as a tape having a width of 25.4 mm and left for 24 hours. The above is preferable. When the adhesive strength is less than 5N / 25.4 mm, there is a tendency that the end portion is lifted when it is attached to an uneven curved surface.

The resin constituting the adhesive layer is not particularly limited, but an acrylic adhesive is preferable from the viewpoints of weather resistance, transparency, yellowing resistance, and the like, and the acrylic adhesive includes a tackifier as necessary. Additives such as ultraviolet absorbers, light stabilizers and antioxidants can be added.

The tensile strength measured based on JIS K 7172 of the brittle laminated label of the present invention is 20 N / 10 mm or more, preferably 25 N / 10 mm or more. If the tensile strength is less than 20 N / 10 mm, the sticking workability is deteriorated because the stiffness does not occur when sticking.

Furthermore, the brittle laminated label of the present invention needs to have a crack angle at 10 ° C. of 85 ° to 140 °, preferably 95 ° to 135 °. The crack angle here is a value measured by fixing the label end in an atmosphere of 10 ° C., bending the label to the colored layer side, and cracking. If the crack angle is 85 degrees or more, the peel force can be peeled without breaking the label when peeled from the release paper of 150 mN / 25.4 mm or less, and if the crack angle is less than 140 degrees, After being attached to the substrate, it becomes difficult to peel without destroying.

When the brittle laminated label of the present invention is applied to a substrate and then peeled off with a hand or an instrument, the film breaks. Although the mechanism of fracture is various, a colored layer having a low tensile fracture strength is often cracked and cannot be restored due to stress strain accompanying peeling.

The brittle laminate label of the present invention is a support in which a colored resin layer is printed on a process film by coating or gravure and dried to form a colored layer, and a colorant is similarly dispersed on the colored layer. It is manufactured by coating the layer forming resin or printing it with gravure and drying it, and then coating the supporting layer with the destruction layer forming resin or printing it with gravure and drying it, and then punching it into a predetermined shape. However, it can also be manufactured by a known laminated label manufacturing method.

As shown in FIG. 1, the laminate 1 of the present invention has a fracture layer 3 on an adhesive layer 4, a support layer 2 thereon, and a colored layer 1 that can be removed by laser light irradiation thereon. Yes. When the laminate is irradiated with laser light, the colored layer 1 is removed in the shape of laser irradiation, the support layer 2 is exposed, and a desired print image or the like is formed by comparing the colors of the colored layer 1 and the support layer 2.

Examples of lasers that can be irradiated include CO2 laser, Nd: YAG laser, excimer laser, semiconductor laser, semiconductor excitation solid laser, Ar laser, N2 / Dye laser, HeCd laser, etc. It is preferable to use a CO2 laser, an Nd: YAG laser or the like that is relatively easy to handle.

One or more brittle laminated labels of the present invention are arranged on release paper. As the release paper, release paper that has been subjected to release treatment by a known method can be used. However, the peel strength of the brittle laminated label is 120 mN / 25.4 mm or less, preferably 100 mN / 25.4 mm or less, particularly preferably 90 mN / What becomes 25.4 mm or less is used.

Using a laser printer, a fragile laminated label of a predetermined size and shape printed with a serial number, etc. is continuously formed on a roll-like release paper, and tens to hundreds of fragile laminated labels are formed. Sheets arranged in succession are formed. Each label is peeled off from the sheet on the release paper one by one and is attached to individual parts and substrates one by one by hand.
When the peeling force of the label from the release paper is 120 mN / 25.4 mm or less and the crack angle is 85 degrees or more, the label is hardly destroyed when peeling the label.

The present invention enables laser printers to individually print differently depending on the purpose, and prints serial numbers and dates for the purpose of product management and quality assurance. It is a brittle laminated film for laser printing for displaying individual information of the above, and it breaks when the label is peeled off after being applied. Therefore, fraud due to reuse of reuse can be prevented, and the workability of attaching is good. A brittle laminate label is provided.

Reference example 1
Acrylic resin KP-1876 (made by Nikka Polymer Co., Ltd.) 50 parts by weight, acrylic resin 2100U7 (made by Nippon Carbide Industries Co., Ltd.): 50 parts by weight, CAB (ethyl acetate 20% solution): double parts, melamine -Based crosslinking agent MS-11 (manufactured by Sanwa Chemical Co., Ltd.): 18 parts by weight, curing catalyst CT-5 (manufactured by Sanwa Chemical Co., Ltd.): 4.5 parts by weight, colorant FPGS-5910B (Daiichi Seika) Industrial Co., Ltd.): 15 parts by weight and MIBK: 22.5 parts by weight were mixed to prepare a black resin solution for a colored layer.

Reference example 2
Acrylic resin 2100U7 (Nippon Carbide Industries Co., Ltd.): 50 parts by weight, Colorant: FPGS-5010W (Daiichi Seika Kogyo Co., Ltd.): 100 parts by weight, Isocyanate-based crosslinking agent Coronate HK (Nippon Polyurethane Industry ( Co., Ltd.): 16 parts by weight, glycol compound: PTMG-1000M (manufactured by Sanyo Chemical Industries, Ltd.): 5 parts by weight, MIBK: 4 parts by weight were mixed to prepare a white resin solution for a support layer.

Reference example 3
Acrylic resin 2100U7 (Nippon Carbide Industries Co., Ltd.): 50 parts by weight, Colorant: FPGS-5010W (Daiichi Seika Kogyo Co., Ltd.): 100 parts by weight, Isocyanate-based crosslinking agent Coronate HK (Nippon Polyurethane Industry ( 16 parts by weight, glycol compound PTMG-1000M (manufactured by Sanyo Chemical Industries, Ltd.): 5 parts by weight, MIBK: 4 parts by weight, acrylic beads art pearl GR-300 (manufactured by Negami Industrial Co., Ltd.) : 0.5 part by weight was mixed to prepare a white resin solution for a fracture layer.

Reference example 4
Acrylic adhesive KP-1384L (manufactured by Nippon Carbide Industries Co., Ltd.): 85 parts by weight, aluminum chelate crosslinking agent CK-401 (manufactured by Nippon Carbide Industries Co., Ltd.): 2 parts by weight, fluorescent whitening agent Kayalite B ( Nippon Shokubai Co., Ltd.): 2 parts by weight, ethyl acetate: 31 parts by weight were mixed to prepare an adhesive solution.

Example 1
The black resin solution for colored layer obtained in Reference Example 1 was applied to a PET film (S75 manufactured by Teijin DuPont Films) and dried at 150 ° C. for 3 minutes to form a colored layer having a thickness of 15 μm.
On this colored layer, the white resin solution for a support layer obtained in Reference Example 2 was applied so that the thickness after drying was 40 μm, and dried at 140 ° C. for 3 minutes, then at 150 ° C. for 2 minutes, A film in which a colored layer and a support layer were laminated was produced.
Next, the white resin solution for the fracture layer obtained in Reference Example 3 was applied to the support layer side of the film in which the colored layer and the support layer were laminated so that the thickness after drying was 60 μm. It dried on conditions, and the laminated body of the colored layer, the support layer, and the destruction layer was obtained.
Furthermore, the pressure-sensitive adhesive solution obtained in Reference Example 4 was applied to release paper A (SLK-70AWP manufactured by Sumika Kogyo Co., Ltd.) having a peel strength of 80 mN / 25.4 mm, dried at 90 ° C. for 2 minutes, A 30 μm pressure-sensitive adhesive layer was formed. The laminate was bonded to the laminate so that the surface of the fracture layer was in contact with the pressure-sensitive adhesive layer, and peeled from the PET film on the colored layer side to produce a brittle laminate label for laser printing.
Tables 1 and 2 show the test results of blending, crackability, pasting workability, and non-reusability of the resulting brittle laminate label.

Example 2, Example 3, Example 4
Laminated body of colored layer, support layer, and breaking layer in the same manner as in Example 1 with the blending amount of acrylic bead art pearl GR-300 of white resin solution for breaking layer being 1 part by weight, 2 parts by weight and 4 parts by weight Got.
Tables 1 and 2 show the test results of blending, crackability, pasting workability, and non-reusability of the obtained laminate.

Example 5
The amount of acrylic bead art pearl GR-300 in the white resin solution for the destructive layer was 4 parts by weight, and a laminate of a colored layer, a support layer and a destructive layer was obtained in the same manner as in Example 1.
Further, as in Example 1, a pressure-sensitive adhesive layer was formed, and the same method as in Example 1 was performed using release paper B (SLB-80W manufactured by Sumika Kogyo Co., Ltd.) having a peel strength of 40 mN / 25.4 mm. A brittle laminate label for laser printing was prepared. Tables 1 and 2 show the test results of blending, cracking property, pasting workability, and non-reusability of the obtained laminate.

Comparative Example 1
A tax quality laminated label for laser printing was produced in the same manner as in Example 1 except that the acrylic resin Art Pearl GR-300, which is a white resin solution for the destructive layer, was not added.
Tables 1 and 2 show the test results of blending, cracking property, pasting workability, and non-reusability of the obtained laminate.

Comparative Example 2
A brittle laminated label for laser printing was prepared in the same manner as in Example 1 except that the blending amount of acrylic bead art pearl GR-300 in the white resin solution for the fracture layer was changed to 10 parts by weight.
Tables 1 and 2 show the test results of blending, crackability, pasting workability, and non-reusability of the obtained laminate.

Comparative Example 3
The amount of acrylic bead art pearl GR-300 in the white resin solution for the destructive layer was 2 parts by weight, and a laminate of a colored layer, a support layer and a destructive layer was obtained in the same manner as in Example 1.
Further, in the same manner as in Example 1, a pressure-sensitive adhesive layer was formed, and laser was released in the same manner as in Example 1 using release paper C (Fujimori Kogyo Co., Ltd. 110S-218) having a peeling force of 200 mN / 25.4 mm. A brittle laminated label for printing was produced. Tables 1 and 2 show the test results of blending, cracking property, pasting workability, and non-reusability of the obtained laminate.

Each physical property was measured under the following conditions.
(1) Crackability A 25.4 mm x 150 mm brittle laminate label with a pressure-sensitive adhesive layer and a release paper of 80 mN / 25.4 mm peel-off is prepared and peeled off from the release paper in an atmosphere of 10 ° C. It stuck on the spatula to the length of 30 mm. The part not pasted from the pasted boundary part was fixed with a metal plate, the label was bent to the colored layer side, and the angle when it was broken was measured with a protractor.
Five labels were measured, and the average of three points of data excluding the maximum and minimum values was taken as the measurement result.

(2) Affixing workability From the brittle laminated label obtained in the example, a tester who produced a laser printed laminate label of 15 mm × 50 mm and put a work gloves in an atmosphere of 10 ° C. Was peeled off from the release paper and affixed to a white painted plate, and it was visually confirmed and evaluated whether or not the colored layer was broken (cracked) during peeling and affixing.
100 labels were attached, and the following criteria were evaluated according to the number of labels destroyed during the attaching operation.
◎: 0 out of 100 breaks ○: 1-2 out of 100 breaks △: 3-5 out of 100 breaks ×: 6 or more out of 100 breaks

(3) A 15 mm × 50 mm brittle laminated label subjected to non-reusable laser printing was applied to a white painted plate and left in a 23 ° C. atmosphere for 72 hours.
Thereafter, the laminate was peeled off from the painted plate using a cutter knife. At that time, the case where the label could not be re-applied due to the destruction of the label was evaluated as “not reusable” and the case where it could be re-applied was evaluated as “reusable”.
The above test was carried out 10 times or more for each sample and evaluated according to the following criteria.
○: Impossible 9 times or more △: Impossible 7-8 times ×: Impossible 6 times or less

(4) Character omission Using "ML-Z9510" manufactured by Keyence Corporation, the letter "A" was printed at an output of 15 W and a scanning speed of 500 mm / second, with thicknesses of 130 μm, 250 μm, and 400 μm, respectively. The release paper was peeled off, and each character was observed from the pressure-sensitive adhesive layer side with transmitted light. The case where the brittle laminate label was not burned out by the laser was indicated as “◯”, and the case where the pressure-sensitive adhesive layer was burned out was indicated as “x”.

(5) Character sharpness From the surface of the sample evaluated for character omission, the end of the printed character was observed using an optical microscope (OLYMPUS BX51) and judged according to the following criteria.
The character end is sharp and clean: ○
Burr is seen at part of the character end: △
Burr is generated at the entire character end: ×

(6) Barcode readability EAN128 pattern barcodes were printed under the same conditions as for character omission. This bar code was read 10 times with a bar code reader, and the case where it could be read 10 times was marked with ◯, and the case where it could not be read once was marked with x.

(7) A sample printed with the EAN128 pattern barcode in the same manner as in the heat resistance barcode reading test was left for 1000 hours in an environment of 150 ° C., and then read 10 times with a barcode reader. The case where it was possible was marked with ○, and the case where it could not be read even once was marked with ×.

FIG. 1 is a cross-sectional view of a label laminate for brittle laser printing including beads in a fracture layer of the present invention.

Explanation of symbols

1. 1. Colored layer 2. Support layer 3. Destructive layer 4. Adhesive layer Bead 6. Release paper

Claims (3)

A brittle laminated label for laser printing that consists of the following (A) to (E) and becomes impossible to reuse due to destruction of the colored layer when peeled off after bonding to a substrate,
The brittle laminated label for laser printing with adhesive (A) + (B) + (C) + (D) has a crack angle at 10 ° C. of 85 ° to 140 °, and is peeled off from the release paper (E). A brittle laminated label for laser printing having a peeling force of 150 mN / 25.4 mm or less.
(A) A colored layer comprising a cross-linked acrylic resin and serving as the outermost layer when the laminate is attached to a substrate,
(B) A support layer comprising a cross-linked acrylic resin having a color difference visible to the colored layer (A) and laminated on the colored layer;
(C) a destructive layer laminated on the support layer (B),
(D) Adhesive layer (E) laminated on the destructive layer (C) Release paper laminated on the adhesive layer (D)   The laminated label for brittle laser printing according to claim 1, wherein the breaking layer (C) contains 0.3 to 4.0 parts by weight of a brittleness imparting component with respect to 100 parts by weight of the acrylic resin.   The brittle laminate label for laser printing according to claim 1 or 2, wherein the brittleness imparting component is an acrylic resin bead.