WO2023243486A1 - Film à base de polyester thermorétractable pour impression laser - Google Patents

Film à base de polyester thermorétractable pour impression laser Download PDF

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Publication number
WO2023243486A1
WO2023243486A1 PCT/JP2023/020970 JP2023020970W WO2023243486A1 WO 2023243486 A1 WO2023243486 A1 WO 2023243486A1 JP 2023020970 W JP2023020970 W JP 2023020970W WO 2023243486 A1 WO2023243486 A1 WO 2023243486A1
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Prior art keywords
heat
laser
film
laser printing
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PCT/JP2023/020970
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English (en)
Japanese (ja)
Inventor
慎太郎 石丸
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東洋紡株式会社
慎太郎 石丸
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Publication of WO2023243486A1 publication Critical patent/WO2023243486A1/fr

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    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B23—MACHINE TOOLS; METAL-WORKING NOT OTHERWISE PROVIDED FOR
    • B23K—SOLDERING OR UNSOLDERING; WELDING; CLADDING OR PLATING BY SOLDERING OR WELDING; CUTTING BY APPLYING HEAT LOCALLY, e.g. FLAME CUTTING; WORKING BY LASER BEAM
    • B23K26/00—Working by laser beam, e.g. welding, cutting or boring
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B32—LAYERED PRODUCTS
    • B32B—LAYERED PRODUCTS, i.e. PRODUCTS BUILT-UP OF STRATA OF FLAT OR NON-FLAT, e.g. CELLULAR OR HONEYCOMB, FORM
    • B32B27/00—Layered products comprising a layer of synthetic resin
    • B32B27/36—Layered products comprising a layer of synthetic resin comprising polyesters
    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B65—CONVEYING; PACKING; STORING; HANDLING THIN OR FILAMENTARY MATERIAL
    • B65D—CONTAINERS FOR STORAGE OR TRANSPORT OF ARTICLES OR MATERIALS, e.g. BAGS, BARRELS, BOTTLES, BOXES, CANS, CARTONS, CRATES, DRUMS, JARS, TANKS, HOPPERS, FORWARDING CONTAINERS; ACCESSORIES, CLOSURES, OR FITTINGS THEREFOR; PACKAGING ELEMENTS; PACKAGES
    • B65D65/00—Wrappers or flexible covers; Packaging materials of special type or form
    • B65D65/38—Packaging materials of special type or form
    • B65D65/40—Applications of laminates for particular packaging purposes
    • C—CHEMISTRY; METALLURGY
    • C08—ORGANIC MACROMOLECULAR COMPOUNDS; THEIR PREPARATION OR CHEMICAL WORKING-UP; COMPOSITIONS BASED THEREON
    • C08J—WORKING-UP; GENERAL PROCESSES OF COMPOUNDING; AFTER-TREATMENT NOT COVERED BY SUBCLASSES C08B, C08C, C08F, C08G or C08H
    • C08J5/00—Manufacture of articles or shaped materials containing macromolecular substances
    • C08J5/18—Manufacture of films or sheets

Definitions

  • the present invention relates to a heat-shrinkable polyester film for laser printing suitable for label applications and the like.
  • heat-shrinkable films have come to be widely used for applications such as label packaging, cap seals, and integrated packaging that both protect glass bottles, plastic bottles, etc. and display products.
  • polyvinyl chloride films have low heat resistance and also have problems such as generating hydrogen chloride gas and causing dioxins when incinerated.
  • polystyrene film has poor solvent resistance, requires the use of ink with a special composition when printing, and must be incinerated at high temperatures, producing a large amount of black smoke with an unpleasant odor when incinerated. There is a problem with doing so. For this reason, polyester heat-shrinkable films that have high heat resistance, easy incineration, and excellent solvent resistance tend to be widely used as shrinkable labels.
  • heat-shrinkable polyester films made of plastic films for laser printing are widely used for distributed goods such as foods, pharmaceuticals, and industrial products.
  • Heat-shrinkable polyester film for laser printing not only protects the contents, but also plays the role of displaying information such as product name, manufacturing date, and raw materials.
  • a laser printable film can be obtained by incorporating a laser-reactive coloring material into a base material, or by applying a coating layer containing a laser-reactive coloring material to a base film.
  • An object of the present invention is to provide a heat-shrinkable polyester film having a laser-printed layer that is free from unevenness, wrinkles, and distortion in laser-printed products after shrinkage.
  • a heat-shrinkable polyester film for laser printing which includes at least one laser printing layer that changes color upon laser irradiation, and which satisfies the following (1) to (3).
  • the shrinkage rate at 80°C in the main shrinkage direction is 30% or more and 80% or less.
  • the reduction rate of shrinkage at 80°C in the main shrinkage direction is 11% or more and 30% or less.
  • Transmittance of 355 nm in the ultraviolet-visible spectrum is 65% or more and 90% or less.
  • the heat-shrinkable polyester film for laser printing according to item 1 characterized in that the maximum shrinkage stress measured in 90°C hot air in the main shrinkage direction is 6 MPa or more and 20 MPa or less.
  • the heat-shrinkable polyester film for laser printing according to item 1 or 2 which has a thickness of 20 ⁇ m or more and 80 ⁇ m or less.
  • the laser printing layer that changes color when irradiated with a laser is made of a metal or metal compound selected from the group consisting of bismuth, gadolinium, neodymium, titanium, antimony, tin, aluminum, calcium, and barium, which enables marking by laser irradiation. 4.
  • thermoforming a heat-shrinkable polyester film for laser printing that is free from unevenness, wrinkles, and distortion in laser printing on products after shrinkage.
  • the heat-shrinkable polyester film for laser printing of the present invention has a film layer that can be printed by laser irradiation (hereinafter referred to as laser irradiation). It must have at least one laser-printed layer (or simply "laser-printed layer") that changes color due to In the present invention, it is preferable that the heat-shrinkable polyester film for laser printing has a laser printing layer over the entire area in the plane direction. Further, the heat-shrinkable polyester film for laser printing of the present invention may be provided with a printing layer having characters or designs other than the laser-printed characters in order to improve the design.
  • the thickness of the heat-shrinkable polyester film for laser printing of the present invention is not particularly limited, but is preferably 5 ⁇ m or more and 100 ⁇ m or less. If the thickness of the heat-shrinkable polyester film for laser printing is thinner than 5 ⁇ m, it is not preferable because not only the visibility of laser printing may be reduced, but also the mechanical strength and fusing seal strength may be reduced. On the other hand, if the thickness of the heat-shrinkable polyester film for laser printing exceeds 100 ⁇ m, it is economically useless for display purposes.
  • the thickness of the heat-shrinkable polyester film for laser printing is more preferably 10 ⁇ m or more and 90 ⁇ m or less, and even more preferably 20 ⁇ m or more and 80 ⁇ m or less.
  • the thickness of the laser printing layer constituting the heat-shrinkable polyester film for laser printing of the present invention is preferably 5 ⁇ m or more and 100 ⁇ m or less. If this thickness is less than 5 ⁇ m, even if the concentration of the laser printing pigment described below is increased, the visibility of the laser printing may deteriorate. On the other hand, if the thickness of the printing layer exceeds 100 ⁇ m, it is economically useless for display purposes.
  • the thickness of the laser printing layer is more preferably 10 ⁇ m or more and 90 ⁇ m or less, and even more preferably 20 ⁇ m or more and 80 ⁇ m or less.
  • all the layers constituting the heat-shrinkable polyester film for laser printing of the present invention may be provided with layers that have been subjected to corona treatment, coating treatment, flame treatment, etc. in order to improve the surface printability. is also possible.
  • Laser printing layer that changes color upon laser irradiation In order to make the printing layer constituting the present invention laser printable, it is necessary to add a laser printing pigment that has the ability to change color upon laser irradiation.
  • the plastic that makes up the heat-shrinkable polyester film for laser marking usually hardly reacts to laser light, so it cannot be printed by laser irradiation.
  • Laser printing pigments are excited by the energy of the laser beam, and the surrounding plastic is carbonized, making printing possible. In addition to the carbonization effect of plastic, some types of laser printing pigments themselves turn black. Printing on the printing layer becomes possible due to the individual or combined effect of this carbonization effect and the color change effect of the laser printing pigment. From the viewpoint of printing density, it is preferable to select a laser printing pigment that has both the carbonizing effect of plastic and its own discoloration effect.
  • laser printing pigments include bismuth, gadolinium, neodymium, titanium, antimony, tin, aluminum, calcium, and barium alone or in their oxides.
  • titanium oxide, calcium carbonate, bismuth trioxide, antimony trioxide, and barium sulfate are preferred, and titanium oxide, calcium carbonate, and bismuth trioxide are more preferred.
  • the particle size of the laser printing pigment is preferably 0.1 ⁇ m or more and 10 ⁇ m or less. If the particle size of the laser printing pigment is less than 0.1 ⁇ m, the color change upon laser irradiation may not be sufficient.
  • the particle size of the laser printing pigment is more preferably 1 ⁇ m or more and 9 ⁇ m or less, and even more preferably 2 ⁇ m or more and 8 ⁇ m or less.
  • the amount of laser printing pigment added to the laser printing layer is preferably 0.05% by mass or more and 50% by mass or less. If the amount of pigment added is less than 0.05% by mass, it is not preferable because the laser print density will not be sufficient. On the other hand, if the amount of pigment added exceeds 50% by mass, the amount (volume) of carbonized plastic will be relatively reduced, so there is a risk that the print density will not be sufficient.
  • the amount of laser printing pigment added is more preferably 0.1% by mass or more and 49% by mass or less, even more preferably 0.15% by mass or more and 48% by mass or less, and 0.2% by mass or more and 47% by mass or less. It is particularly preferable.
  • the amount of laser-printed pigment added to the entire laser-printed layer can be determined by proportionally dividing the thickness ratio of each layer and the amount of added laser-printed pigment.
  • the method of blending the laser printing pigment it can be added at any stage of manufacturing the resin that becomes the raw material for the laser printing layer or the film that becomes the laser printing layer.
  • the stage of manufacturing resin there are methods such as blending a slurry of particles dispersed in a solvent with plastic raw materials using a vented kneading extruder, or using a method of blending dried particles and plastic resin using a kneading extruder.
  • Another example is a method of blending (masterbatching).
  • masterbatching a method in which a masterbatch containing a laser-printed pigment is used as a raw material for the film is preferred.
  • various additives other than the laser printing pigment may be added as necessary, such as waxes, antioxidants, antistatic agents, A crystal nucleating agent, a thinner, a heat stabilizer, a coloring pigment, a coloring inhibitor, an ultraviolet absorber, etc. can be added.
  • fine particles as a lubricant to improve slipperiness. Any fine particles can be selected as the fine particles.
  • inorganic fine particles include silica, alumina, kaolin, lead white, titanium white, zeolite, zinc white, lithopone, etc.
  • organic fine particles include acrylic particles, melamine particles, silicone particles, and cross-linked particles. Examples include polystyrene particles, carbon black, iron oxide, and the like.
  • the average particle diameter of the fine particles can be appropriately selected as necessary within the range of 0.05 to 3.0 ⁇ m when measured using a Coulter counter.
  • the lower limit of the fine particle content is preferably 0.01% by mass, more preferably 0.015% by mass, and even more preferably 0.02% by mass. If it is less than 0.01% by mass, slipperiness may decrease.
  • the upper limit is preferably 1% by mass, more preferably 0.2% by mass, and still more preferably 0.1% by mass. If it exceeds 1% by mass, it is not preferable because problems such as decreased surface smoothness and blurred printability may occur.
  • the method of blending particles into the laser printing layer they can be added at any stage of manufacturing the plastic raw material, and the particles can be added at any stage of manufacturing the plastic raw material, and the particles can be added in accordance with the above "1.2.1. Types of laser printing pigments, amount added, and method of addition". The same method can be adopted.
  • the heat-shrinkable polyester film for laser printing of the present invention has a printing layer, a smooth layer, a surface protection layer, an antistatic layer, etc. as layers other than the above-mentioned laser printing layer. You can leave it there.
  • the heat-shrinkable polyester film for laser printing of the present invention may be provided with letters or designs for the purpose of improving design.
  • known materials such as ink for gravure printing and ink for flexographic printing can be used.
  • the number of printed layers may be one or multiple layers. In order to improve the design by printing in multiple colors, it is preferable to have a printing layer consisting of multiple layers.
  • the printed layer may be located either in the outermost layer or in the middle layer.
  • the heat-shrinkable polyester film for laser printing of the present invention has a layer for the purpose of making the film suitable for slipping in addition to printing by laser irradiation.
  • the slippery layer is a surface layer, and it is preferable to add fine particles as a lubricant to the slippery layer, which may be on one side or both sides. Any fine particles can be selected as the fine particles.
  • inorganic fine particles include silica, alumina, kaolin, lead white, titanium white, zeolite, zinc white, lithopone, etc.
  • organic fine particles include acrylic particles, melamine particles, silicone particles, and cross-linked particles. Examples include polystyrene particles, carbon black, iron oxide, and the like.
  • the average particle diameter of the fine particles can be appropriately selected as necessary within the range of 0.05 to 3.0 ⁇ m when measured using a Coulter counter.
  • the lower limit of the fine particle content is preferably 0.01% by mass, more preferably 0.015% by mass, and even more preferably 0.02% by mass. If it is less than 0.01% by mass, slipperiness may decrease.
  • the upper limit is preferably 1% by mass, more preferably 0.2% by mass, and still more preferably 0.1% by mass. If it exceeds 1% by mass, it is not preferable because problems such as decreased surface smoothness and blurred printability may occur.
  • the heat shrinkage rate at 80°C in the main shrinkage direction is less than 30%, when used as a film for beverage labels or lunch box packaging, the amount of shrinkage will be small, resulting in label wrinkles and sagging after heat shrinkage. So I don't like it.
  • the shrinkage rate at 80° C. is more preferably 35% or more, particularly preferably 40% or more, and most preferably 45% or more. There is no problem even if the heat shrinkage rate at 80°C in the main shrinkage direction is higher than 80%, but if the shrinkage rate at 80°C is 80% or less, the film can be formed with good production efficiency.
  • the 90°C heat shrinkage rate in the main shrinkage direction is preferably 35% or more and 80% or less. If the heat shrinkage rate at 90°C in the main shrinkage direction is less than 35%, when used as a film for beverage labels or lunch box packaging, the amount of shrinkage will be small, resulting in label wrinkles and sagging after heat shrinkage. So I don't like it.
  • the 90°C heat shrinkage rate in the main shrinkage direction is more preferably 40% or more, particularly preferably 45% or more. There is no problem even if the 90°C heat shrinkage rate in the main shrinkage direction is higher than 80%, but if the 90°C heat shrinkage rate in the main shrinkage direction is 80% or less, a film can be formed with good production efficiency.
  • the heat-shrinkable polyester film for laser printing of the present invention can be After shrinking by 10% in the shrinkage direction, the reduction rate of shrinkage at 80° C. in the main shrinkage direction is 11% or more and 30% or less. Normally, when a heat-shrinkable film is shrunk by 10%, the heat shrinkage rate decreases by the amount of shrinkage, that is, by 10%. In this case, even after the object to be coated is heat-shrinked, the label still has a heat-shrinkage rate (heat-shrinkage performance).
  • the heat generated when the label is irradiated with a laser increases the thermal contraction of the corresponding portion, making it more likely that deformation and holes will occur.
  • it was necessary to reduce the shrinkage rate before shrinkage making it difficult to use for applications that require a high shrinkage rate such as irregularly shaped bottles, and using heat that is not versatile. There was a risk that it would become a shrink film. Therefore, in order to achieve both a high shrinkage rate before shrinkage and a low shrinkage rate (high heat resistance) after shrinkage, the present inventors found that it is necessary to reduce the heat shrinkage rate at 80°C in the main shrinkage direction after shrinking by 10%.
  • the ratio it is preferable to set the ratio to 11% or more. The conditions necessary to realize this characteristic will be described later. If the reduction rate of the 80° C. heat shrinkage rate in the main shrinkage direction after shrinking by 10% is less than 11%, it is not preferable because the heat resistance after shrinkage may be insufficient. On the other hand, the higher the reduction rate of this shrinkage rate is, the more preferable it is, but if it is 30% or less, a film can be formed with good production efficiency.
  • the reduction rate of the 80° C. heat shrinkage rate in the main shrinkage direction after shrinking by 10% is preferably 12% or more and 29% or less, more preferably 13% or more and 28% or less.
  • the heat-shrinkable polyester film for laser printing of the present invention has the following properties: It is preferable that the 80° C. heat shrinkage rate in the main shrinkage direction after shrinking by 10% is 20% or more and 60% or less. This characteristic corresponds to the heat resistance described above with respect to the reduction rate of the heat shrinkage rate at 80° C. in the main shrinkage direction after shrinking by 10%. If the 80°C heat shrinkage rate in the main shrinkage direction after 10% shrinkage is less than 20%, the 80°C heat shrinkage rate in the main shrinkage direction tends to be less than 30%, which is not preferable.
  • the 80°C heat shrinkage rate in the main shrinkage direction after 10% shrinkage exceeds 60%, it is not preferable because the heat resistance after shrinkage tends to be insufficient.
  • This shrinkage rate is more preferably 21% or more and 59% or less, and even more preferably 22% or more and 58% or less.
  • the heat-shrinkable polyester film for laser printing of the present invention has a maximum shrinkage stress measured in 90°C hot air in the main shrinkage direction of 6 MPa or more. It is preferable that it is 20 MPa or less. If this maximum shrinkage stress is less than 6 MPa, it is not preferable because the reduction rate of the 80°C shrinkage rate in the main shrinkage direction after shrinking by 10% in the main shrinkage direction with 100°C hot air tends to be less than 10%.
  • the maximum shrinkage stress exceeds 20 MPa, there is a risk that too much force will be applied to the object to be covered when the film shrinks, resulting in deformation of the object to be covered, or poor finish (so-called sink marks) when the film is shrunk as a label. may become large.
  • the maximum shrinkage stress is more preferably 6.5 MPa or more and 19.5 MPa or less, and even more preferably 7 MPa or more and 19 MPa or less.
  • the heat-shrinkable polyester film for laser printing of the present invention has a transmittance at 355 nm in the UV-visible spectrum of 65% or more and 90% or less.
  • the transmittance at 355 nm in the UV-visible spectrum indicates the ability to absorb ultraviolet (UV) lasers. The lower the transmittance is, the more likely it is to absorb laser energy and change color, and the density of laser printing tends to be higher.
  • UV ultraviolet
  • the transmittance at 355 nm in the ultraviolet-visible spectrum exceeds 90%, it becomes difficult to make the difference in color L* value of the laser-printed portion 1.0 or more.
  • the transmittance at 355 nm in the ultraviolet-visible spectrum is preferably 66% or more and 89% or less, more preferably 67% or more and 88% or less.
  • the heat-shrinkable polyester film for laser printing of the present invention has the following characteristics: It is preferable that the absolute value of the difference in color L* values (hereinafter sometimes simply referred to as "difference in L* values”) is 1.0 or more and 10.0 or less. If this difference is less than 1.0, the color tone of the printed area and the non-printed area will be close, making it difficult to visually recognize the printing. On the other hand, if the difference in L* value exceeds 10.0, the printing becomes easier to see, but the laser irradiation power needs to be increased accordingly, which increases the damage to the heat-shrinkable polyester film for laser printing. This is undesirable because it tends to cause problems such as holes and deformation.
  • the difference in L* values is more preferably 1.5 or more and 9.5 or less, and even more preferably 2.0 or more and 9.0 or less.
  • the polyester used in the heat-shrinkable polyester film for laser printing of the present invention is ethylene. It has a terephthalate unit.
  • the ethylene terephthalate unit is preferably 40 mol% or more, more preferably 50 mol% or more, and even more preferably 55 mol% or more in 100 mol% of the constituent units of the polyester.
  • the above-mentioned structural unit shall mean a monomer unit of polyhydric alcohol and polyhydric carboxylic acid that constitute the copolymer.
  • the heat-shrinkable polyester film for laser printing of the present invention contains at least 5 mol% or more of at least one kind from the group consisting of butanediol, diethylene glycol, and ⁇ -caprolactone in 100 mol% of the total polyester resin component. It is preferable.
  • the reduction rate of shrinkage at 80°C in the main shrinkage direction after shrinking by 10% in the main shrinkage direction with 100°C hot air The inventors of the present invention have found that it is easy to increase the ratio to 10% or more.
  • the main shrinkage rate after shrinking by 10% in the main shrinkage direction with hot air at 100°C makes it easier to reduce the 80°C shrinkage rate of 10% or more. If the content of at least one component selected from butanediol, diethylene glycol, and ⁇ -caprolactone is less than 5 mol%, the relaxation of short chain components such as ethylene glycol becomes relatively large, and the There is a possibility that the shrinkage rate (before 10% shrinkage treatment in the main shrinkage direction with 100° C. hot air) will be less than 30%.
  • the content of these long chain components is more preferably 6 mol% or more and 29 mol% or less, and even more preferably 7 mol% or more and 28 mol% or less.
  • the polyester raw material used for the heat-shrinkable polyester film for laser printing of the present invention further includes units derived from one or more monomers that can be an amorphous component other than the units derived from butanediol, diethylene glycol, and ⁇ -caprolactone.
  • the total amount) is preferably 18 mol% or more based on 100 mol% of all polyester resin components. If the amorphous component is less than 18 mol%, the heat shrinkage properties will be poor.
  • the monomer that can become an amorphous component is preferably 20 mol% or more and 25 mol% or less in 100 mol% of the polyhydric alcohol component or 100 mol% of the polyhydric carboxylic acid component in the total polyester resin.
  • monomers that can be amorphous components include neopentyl glycol, 1,4-cyclohexanedimethanol, isophthalic acid, 1,4-cyclohexanedicarboxylic acid, 2,6-naphthalene dicarboxylic acid, and 1,3-propanediol. , 2,2-diethyl-1,3-propanediol, 2-n-butyl-2-ethyl-1,3-propanediol, 2,2-isopropyl-1,3-propanediol, 2,2-di- Examples include n-butyl-1,3-propanediol and hexanediol. Among these, neopentyl glycol, 1,4-cyclohexanedimethanol, and isophthalic acid are preferred.
  • the structural unit consisting of isophthalic acid and butanediol is a structural unit derived from butanediol, and is also a structural unit derived from one or more monomers that can be an amorphous component. Therefore, in the present invention, the content of the structural unit consisting of isophthalic acid and butanediol is counted as a structural unit derived from butanediol, and also as a structural unit derived from one or more monomers that can be an amorphous component. shall be taken as a thing.
  • the content of structural units derived from butanediol refers to the total content of the structural units consisting of isophthalic acid and butanediol, and the content of structural units consisting of terephthalic acid and butanediol.
  • the content of constituent units derived from one or more monomers that can become an amorphous component is determined by the content of constituent units consisting of isophthalic acid and butanediol and the content of constituent units consisting of isophthalic acid and ethylene glycol. It refers to the total content of the constituent units derived from one or more monomers that can become amorphous components. The same applies to the relationship between the content of constituent units derived from ⁇ -caprolactone and the content of constituent units derived from one or more monomers that can be an amorphous component.
  • Dicarboxylic acid components other than those mentioned above constituting the polyester used in the present invention include aromatic dicarboxylic acids such as orthophthalic acid; aliphatic dicarboxylic acids such as adipic acid, azelaic acid, sebacic acid, and decanedicarboxylic acid; and alicyclic dicarboxylic acids. Examples include acids.
  • an aliphatic dicarboxylic acid for example, adipic acid, sebacic acid, decanedicarboxylic acid, etc.
  • the content is preferably less than 3 mol% (in 100 mol% of the dicarboxylic acid component).
  • Heat-shrinkable polyester films for laser printing obtained using polyesters containing 3 mol % or more of these aliphatic dicarboxylic acids have insufficient film stiffness during high-speed installation.
  • the polyester does not contain trivalent or higher polycarboxylic acids (for example, trimellitic acid, pyromellitic acid, anhydrides thereof, etc.).
  • trimellitic acid for example, trimellitic acid, pyromellitic acid, anhydrides thereof, etc.
  • anhydrides thereof etc.
  • polyhydric alcohol components other than those mentioned above constituting the polyester used in the present invention include aromatic diols such as bisphenol A.
  • the polyester used in the present invention is a polyester whose glass transition point (Tg) is adjusted to 50 to 80°C by appropriately selecting the amounts of butanediol, diethylene glycol, and ⁇ -caprolactone, and the amount of monomers that can become amorphous components. preferable. Tg is more preferably 52°C or more and 78°C or less.
  • the polyester used in the present invention contains a diol having 8 or more carbon atoms (for example, octanediol, etc.) or a polyhydric alcohol of 3 or more valences (for example, trimethylolpropane, trimethylolethane, glycerin, diglycerin, etc.) It is preferable not to do so.
  • a diol having 8 or more carbon atoms for example, octanediol, etc.
  • a polyhydric alcohol of 3 or more valences for example, trimethylolpropane, trimethylolethane, glycerin, diglycerin, etc.
  • the most preferable polyester is 1 to 25 mol% of butylene terephthalate units, 1 to 25 mol% of units consisting of ⁇ -caprolactone and terephthalic acid, and 2 to 50 mol% of these total units, out of 100 mol% of all polyester constituent units.
  • the polyester contains 18 to 25 mol% of units consisting of a monomer that can be an amorphous component and terephthalic acid, and the remainder is ethylene terephthalate units. Note that an amorphous unit in which part of terephthalic acid is replaced with isophthalic acid may be included.
  • various additives may be added as necessary, such as waxes, antioxidants, antistatic agents, crystal nucleating agents, and thinning agents. , heat stabilizers, coloring pigments, coloring inhibitors, ultraviolet absorbers, etc. can be added.
  • fine particles as a lubricant to the resin forming the heat-shrinkable polyester film for laser printing of the present invention to improve the workability (slip properties) of the film.
  • Any fine particles can be selected.
  • inorganic fine particles include silica, alumina, titanium dioxide, calcium carbonate, kaolin, barium sulfate, etc.
  • organic fine particles include acrylic resin, etc.
  • examples include particles, melamine resin particles, silicone resin particles, and crosslinked polystyrene particles.
  • the average particle size of the fine particles is preferably in the range of 0.05 to 3.0 ⁇ m.
  • the average particle diameter of the fine particles is a value measured using a Coulter counter.
  • the above-mentioned particles into the resin forming the heat-shrinkable polyester film for laser printing of the present invention can be added at any stage of producing the polyester resin; It is preferable to add the compound as a slurry dispersed in ethylene glycol or the like at a stage after the end of the transesterification reaction or before the start of the polycondensation reaction to proceed with the polycondensation reaction.
  • a method of blending a slurry of particles dispersed in ethylene glycol or water with a polyester resin raw material using a kneading extruder with a vent or a method of blending dried particles and a polyester resin raw material using a kneading extruder It is also preferable to carry out the method by blending the two.
  • the heat-shrinkable polyester film for laser printing of the present invention is produced by melt-extruding the polyester raw material described above using an extruder to form an unstretched film. can be obtained by stretching the unstretched film by a predetermined method shown below.
  • the present invention will be described by taking as an example the sequential biaxial stretching in which horizontal uniaxial stretching or longitudinal stretching is followed by horizontal stretching, which is a general method for producing a shrink film. It may be a sequential biaxial stretching that carries out the following, or a simultaneous biaxial stretching that stretches in the longitudinal and transverse directions at the same time.
  • an unstretched film can be obtained by rapidly cooling the sheet-shaped molten resin after extrusion.
  • a method of rapidly cooling the molten resin a method of obtaining a substantially unoriented resin sheet by casting the molten resin from a die onto a rotating drum and rapidly cooling and solidifying it can be suitably employed.
  • the stretching ratio in the longitudinal direction is preferably 2 times or less.
  • the lower limit of the longitudinal stretching ratio is 1x (no stretching). If the longitudinal stretching ratio is greater than 2 times, the molecular chains will be oriented not only in the transverse direction, which is the main shrinkage direction, but also in the longitudinal direction, which will inhibit the movement of the molecular chains that try to relax in the transverse direction. This is not desirable because it can be considered.
  • the upper limit of the longitudinal stretching ratio is more preferably 1.8 times or less, and even more preferably 1.6 times or less.
  • a particularly preferable longitudinal stretching ratio is 1 times the lower limit.
  • the stretching ratio in the longitudinal direction is preferably 2 times or more and 5 times or less. If the stretching ratio in the longitudinal direction is less than 2 times, it becomes difficult to make the 80°C heat shrinkage rate in the main shrinkage direction 30% or more and the 90°C heat shrinkage rate 35% or more. On the other hand, if the stretching ratio exceeds 5 times, the stretching stress becomes too high and the film is likely to break, which is not preferable.
  • the stretching ratio in the longitudinal direction is more preferably 2.5 times or more and 4.5 times or less, and even more preferably 3 times or more and 4 times or less.
  • longitudinal stretching can be either one-stage stretching or multi-stage stretching of two or more stages.
  • longitudinal stretching is the main contraction direction, relaxation in the longitudinal direction is required after stretching in the longitudinal direction. The detailed conditions will be explained below in [3-2-4] Heat treatment/relaxation conditions after stretching in the shrinkage direction.
  • the lateral stretching in the present invention is performed at a temperature of Tg + 10°C or more and Tg + 30°C or less, and 3 times or more and 6 times or less, with both ends in the width direction being gripped with clips in a tenter. Do this so that the magnification is as follows.
  • the temperature for transverse stretching is more preferably Tg+12°C or higher, further preferably Tg+14°C or higher, more preferably Tg+28°C or lower, and even more preferably Tg+26°C or lower.
  • the transverse stretching ratio is more preferably 3.5 times or more, further preferably 3.7 times or more, more preferably 5.5 times or less, and even more preferably 5 times or less.
  • the stretching temperature exceeds Tg + 30°C, the thickness accuracy of the film tends to decrease, but by controlling the stretching temperature to Tg + 30°C or less, the thickness accuracy of the film can be increased, which is preferable. .
  • the stretching temperature is lower than Tg+10°C, the orientation in the width direction will become too large, making it easy to break during transverse stretching, which is not preferable.
  • the polyester raw material contains 5 mol% or more of long chain components such as butanediol, diethylene glycol, and ⁇ -caprolactone, and by relaxing in the width direction, it can be reduced by 10% in the main shrinkage direction with hot air at 100°C. After shrinkage, the reduction rate of the 80°C shrinkage rate in the main shrinkage direction can be easily set to 10% or more. It has conventionally been thought that heat treatment is meaningless if the temperature at which the material is relaxed in the width direction is lower than the transverse stretching temperature.
  • the relaxation temperature is higher than the transverse stretching temperature, it becomes difficult to achieve a thermal shrinkage rate (before shrinkage) of 30% or more in the main shrinkage direction at 80°C.
  • the relaxation temperature is preferably -10°C or more and 0°C or less, more preferably -9°C or more and -1°C or less relative to the transverse stretching temperature.
  • the relaxation rate in the width direction is preferably 3% or more and 20% or less.
  • the relaxation rate is less than 3%, the relaxation of the short chain components will not be sufficient, and after shrinking by 10% in the main shrinkage direction with 100°C hot air, the reduction rate of the shrinkage rate at 80°C in the main shrinkage direction will be 10% or more. It may be difficult to do so.
  • the relaxation rate exceeds 20%, it becomes difficult to achieve a heat shrinkage rate (before shrinkage) of 30% or more in the main shrinkage direction at 80°C.
  • the relaxation rate in the width direction is preferably 4% or more and 19% or less, more preferably 5% or more and 18% or less.
  • the residence time in the relaxing step is preferably 1 second or more and 9 seconds or less.
  • the relaxation time is less than 1 second, the short chain components will not be sufficiently relaxed, and after shrinking by 10% in the main shrinkage direction with 100°C hot air, the reduction rate of the shrinkage rate at 80°C in the main shrinkage direction will be 10%. It becomes difficult to do so.
  • the relaxation time exceeds 9 seconds, the equipment becomes too large, which is not preferable.
  • the relaxation time is more preferably 1.5 seconds or more and 8.5 seconds or less, and even more preferably 2 seconds or more and 8 seconds or less.
  • laser types that can be used for laser printing on the heat-shrinkable polyester film for laser printing of the present invention include CO2 laser (10600 nm), YAG laser (1064 nm), and YVO4 laser. (1064 nm), fiber laser (1064, 1090 nm), green laser (532 nm), and UV laser (355 nm).
  • the type of laser used for laser printing in the present invention is not particularly limited, but CO 2 laser is often used to burn out plastic, and is used for purposes different from printing, which is the gist of the present invention. Because it is often used, it is not preferred as a laser source.
  • YAG laser, YVO 4 laser, fiber laser, green laser, and UV laser are preferable as laser sources, and YAG laser, fiber laser, and UV laser are more preferable, and UV laser is particularly preferable because it causes less thermal damage.
  • Commercially available devices can be used for laser printing, and representative examples include LM-2550 (YAG laser) manufactured by Brother Industrial Printing, MX-Z2000H-V1 (fiber laser) manufactured by Omron, and 8028 Trotec Speedy 100 flexx manufactured by Trotec. (fiber laser), Keyence MD-X1000 (YVO4 laser), MD-U1000C (UV laser), etc.
  • the specifications and settings that can be set differ depending on the device manufacturer and model, and also vary depending on the film being printed, so it is difficult to generalize, but we recommend using the Keyence MD-U1000C (UV laser, wavelength 355 nm). Examples are as follows.
  • the laser power is preferably 20% or more and 80% or less of the output of the maximum device specification of 13W. If the output is less than 20%, the print density will decrease and visibility will decrease, which is not preferable. If the output is 80% or more, holes will occur in the display, which is not preferable.
  • the output is more preferably 25% or more and 75% or less, and even more preferably 30% or more and 70% or less.
  • the pulse frequency is preferably 10 kHz or more and 100 kHz or less. If the frequency is less than 10 kHz, the laser energy per irradiation becomes high and the thickness reduction rate of the printed area tends to exceed 80 vol%, which is not preferable.
  • the frequency exceeds 100 kHz, it is easy to reduce the thickness of the printed part to 80 vol% or less, but it may be difficult to make the difference in color L* value of the printed part to 1 or more. It is more preferably 15 kHz or more and 95 kHz or less, and even more preferably 20 kHz or more and 90 kHz or less.
  • the scan speed is preferably 10 mm/sec or more and 3000 mm/sec or less. If the scanning speed is less than 10 mm/sec, the printing speed will be extremely low, which will slow down the production speed of the display, which is not preferable.
  • the scan speed is more preferably 100 mm/second or more and 2900 mm/second or less, and even more preferably 200 mm/second or more and 2800 mm/second or less.
  • Display body The display body of the present invention is formed by covering at least a portion of the outer periphery of an object to be packaged with the heat-shrinkable polyester film for laser printing of the present invention, and then heat-shrinking the film.
  • Items to be packaged include plastic bottles for food storage, polyethylene containers used for shampoos and conditioners, various bottles, cans, plastic containers for sweets and lunch boxes, paper boxes, etc. Can be done.
  • labels made from heat-shrinkable polyester films do not have to cover the entire container, but only a portion, such as a bottle lid (cap seal), before being completely attached to the container. It may also be a preform.
  • the label when covering such packaging objects by heat-shrinking a label obtained from a heat-shrinkable polyester film, the label is heat-shrinked by about 2 to 15% and adheres to the packaging object.
  • the difference in color L* value between the laser printed portion and the non-printed portion after laser printing is 1.0 or more and 10 or less.
  • Labels can be made by applying an organic solvent slightly inward from the edge of one side of a rectangular film, then immediately rolling the film, overlapping the edges, and gluing it to form a label; or by rolling it. Apply an organic solvent slightly inward from the edge of one side of the film that has been rolled up into a shape, immediately roll the film, overlap the ends and glue them together, form a tube, and cut the resulting product into a label. .
  • organic solvent for adhesion cyclic ethers such as 1,3-dioxolane or tetrahydrofuran are preferred.
  • aromatic hydrocarbons such as benzene, toluene, xylene and trimethylbenzene
  • halogenated hydrocarbons such as methylene chloride and chloroform
  • phenols such as phenol, or mixtures thereof
  • the evaluation method for heat-shrinkable polyester films for laser printing is as follows. A sample of the non-printed part was cut out from a part 1 mm or more away from the printed part or the melt-cut seal part and used as a sample.
  • a heat-shrinkable film for laser printing was applied to a metal frame (FIG. 1) with an inner dimension of 160 mm square and a frame thickness of 20 mm, and was subjected to a 10% shrinkage treatment. Specifically, after cutting the film to 150 mm in the longitudinal direction x 200 mm in the width direction, mark lines are placed so that the interval in the width direction is 178 mm ( Figure 2), and the mark lines are aligned with the inner dimensions of the metal frame. A film was pasted (the gauge line interval of the film was 178 mm, the metal frame interval was 160 mm, and the relaxation rate was 10%).
  • the metal frame with the film attached was inserted into a hot air oven (STPH-102 manufactured by ESPEC) with a small window of 25 mm in height x 200 mm in width in the door, and the film was shrunk by 10% in the width direction.
  • a square sample of 10 cm x 10 cm was cut from the center of the 10% shrink treated film and immersed in warm water at 80°C ⁇ 0.5°C for 10 seconds under no load to shrink it. It was immersed in water at ⁇ 0.5°C for 10 seconds, pulled out from the water, and its longitudinal and lateral dimensions were measured, and the respective heat shrinkage rates were determined according to Equation 1 above.
  • the direction in which the thermal shrinkage rate was large was defined as the main shrinkage direction.
  • Glass transition point (Tg) Weigh 5.0 ⁇ 0.2 mg of the sample film in a TA Instruments T-zero pan or aluminum pan (flat plate shape), and heat it for 30 seconds on a hot plate heated to 300 °C to melt the sample. I let it happen. Thereafter, the sample was taken out from the hot plate with tweezers and immediately immersed in liquid nitrogen for 1 minute to prepare a melted and rapidly cooled sample.
  • a film (diameter 4.5 mm) obtained by stacking films and punching them into a circular shape was used so as to improve adhesion to the bottom of the pan.
  • Good adhesion to the bottom of the pan means that the film sample does not bend inside the pan when the sample is sealed in the pan, and there is no space between the stacked films when the film is firmly pressed with the lid.
  • the film before punching may have wrinkles, it is preferable to smooth out the wrinkles when punching the sample.
  • the shape and size of the punched sample are not limited to the above-mentioned ones, as long as the sample does not bend and fits on the bottom of the pan.
  • the prepared melt-quenched sample was measured using a temperature-modulated differential scanning calorimeter (DSC) "DSC250" (manufactured by TA Instruments) in MDSC (registered trademark) heat-only mode at an average heating rate of 2°C/min and a modulation period. Measurements were taken for 40 seconds to obtain reverse heat flow. In the reverse heat flow obtained in the measurement, Tg, which appears as a signal that changes stepwise from the baseline, was determined. Specifically, draw an extension line of the baseline of each heat flow on the lower temperature side and higher temperature side than Tg, find the intersection with the tangent at the inflection point (Tg), and read the value of the horizontal axis at this intersection. , the average value of the low temperature side and high temperature side was taken as Tg.
  • DSC temperature-modulated differential scanning calorimeter
  • MDSC registered trademark
  • the printing machine uses an ultraviolet (UV) laser marker (MD-U1000, manufactured by Keyence Corporation) with a wavelength of 355 nm, and the laser is operated under the following conditions: laser power 40%, scan speed 1000 mm/s, pulse frequency 40 kHz, spot variable -20. Irradiated. Deformation of the label was determined based on the following criteria. Judgment ⁇ : There are no holes or distortions in the laser irradiation area Judgment ⁇ : There are holes or distortions in the laser irradiation area
  • the printing machine uses an ultraviolet (UV) laser marker (MD-U1000, manufactured by Keyence Corporation) with a wavelength of 355 nm, and the laser is operated under the following conditions: laser power 40%, scan speed 1000 mm/s, pulse frequency 40 kHz, spot variable -20. Irradiated.
  • UV ultraviolet
  • a spectroscopic color difference meter manufactured by Nippon Denshoku Co., Ltd., ZE-6000 was used, and the L* value of each printed area and non-printed area of one label after laser printing was determined by the reflection method. It was measured. Note that the sample used for the measurement was the flat part of the label.
  • the specific method for measuring the printed area is as follows. Among the characters printed as "12345ABCDE", a 3 cm square sample was cut out so as to include all "B" (at this time, characters other than "B” may be included) and measured.
  • a 6 ⁇ sample stand (the opening that the measurement light hits is about 1 cm in diameter) and a 6 ⁇ sight were used as the measurement light source of the color difference meter, so that the letter "B" would fit into the opening of the sample stand.
  • the sample stand may be changed as necessary (for example, 10 ⁇ , 30 ⁇ , etc.). Even if the print protrudes, a portion of the print only needs to enter the opening of the sample stage and be illuminated by the measurement light.
  • the non-printed area a sample of 3 cm square was cut out from the unprinted area, and the color L* value was measured using a color difference meter with a diameter of 6 mm and a sample stand.
  • the viewing area of the color difference meter and the sample stand may be changed to 10 ⁇ , 30 ⁇ , etc. as necessary, and in that case, the sample size should be such that it covers the opening of the sample stand (so that the measurement light does not leak). It can be any size.
  • polyesters B to J having the compositions shown in Table 1 were obtained.
  • polyester D a composite oxide pigment of bismuth and neodymium (TOMATEC COLOR 42-920A manufactured by TOMATEC Co., Ltd.; average particle size 1 ⁇ m) was added as a laser printing pigment at a ratio of 5% by mass to the polyester.
  • polyester E a mica pigment coated with antimony-doped tin oxide (Iriotec (R) 8825 manufactured by MERCK; average particle size less than 15 ⁇ m) was used as a laser printing pigment in an amount of 5% by mass based on the polyester. added in proportion.
  • polyester F SiO 2 (Silysia 266 manufactured by Fuji Silysia Co., Ltd.; average particle size: 1.5 ⁇ m) was added as a lubricant at a ratio of 7,000 ppm to the polyester.
  • TPA is terephthalic acid
  • IPA is isophthalic acid
  • EG is ethylene glycol
  • BD is 1,4-butanediol
  • NPG is neopentyl glycol
  • CHDM is 1,4-cyclohexanedimethanol
  • TMG is polytetramethylene.
  • the glycol, CL, is ⁇ -caprolactone
  • DEG is diethylene glycol (which may contain by-products during polymerization).
  • chemically recycled terephthalic acid was used for polymerization of polyester raw material J.
  • each polyester was suitably made into chips.
  • Polyester raw material I was PET copolymerized with 10 mol% of isophthalic acid obtained by mechanically recycling a PET bottle, and had an intrinsic viscosity of 0.75 dl/g.
  • Example 1 As raw materials for the printing layer (layer A), polyester A, polyester D, and polyester I were mixed at a mass ratio of 85:3:12, and as raw materials for the B layer, polyester A, polyester F, and polyester I were mixed at a mass ratio of 830:7:10. mixed with.
  • the mixed raw materials for layer A and layer B were each melted in separate extruders.
  • the respective molten resins were joined by a feed block in the middle of the channel, discharged from a T-die, and taken off while cooling on a chill roll whose surface temperature was set to 30° C. to obtain an unstretched laminated film.
  • the Tg of the unstretched film was 65°C.
  • the obtained unstretched film was introduced into a transverse stretching machine (tentter), and while holding both ends of the film with clips, it was preheated until the film temperature reached 90°C, and then, the film temperature was 85°C and the film was stretched 4 times in the width direction. It was stretched .5 times. Next, heat treatment at 80° C. and 10% relaxation treatment in the width direction were performed. Next, the uniaxially stretched film of about 40 ⁇ m was wound into a roll while cutting and removing both edges of the film. The properties of the obtained film were evaluated by the method described above. The film forming conditions and evaluation results are shown in Table 2. The film had no practical problems in both shrinkage finish and laser printing evaluation.
  • the obtained unstretched film is introduced into a longitudinal stretching machine in which a plurality of roll groups are consecutively arranged, and after being preheated with a preheating roll until the film temperature reaches 80°C, it is rotated at a low speed with a surface temperature of 80°C. Using the difference in rotational speed between the roll and a high-speed rotating roll whose surface temperature was set to 80, the film was stretched 1.3 times in the longitudinal direction.
  • the film after longitudinal stretching is introduced into a transverse stretching machine (tentter), and with both ends of the film held by clips, the film is preheated until the film temperature reaches 105°C, and then, the film temperature is 88°C and the film is stretched 4 times in the width direction. It was stretched .5 times. Next, heat treatment at 82° C. and 15% relaxation treatment in the width direction were performed. Next, the biaxially stretched film of about 20 ⁇ m was wound up into a roll while cutting and removing both edges of the film. The properties of the obtained film were evaluated by the method described above. The film forming conditions and evaluation results are shown in Table 2. The film had no practical problems in terms of shrinkage finish and laser printing evaluation.
  • the obtained unstretched film is introduced into a longitudinal stretching machine in which a plurality of roll groups are successively arranged, and after being preheated with a preheating roll until the film temperature reaches 82°C, it is rotated at a low speed with a surface temperature of 82°C.
  • the film was stretched 3.6 times in the longitudinal direction by utilizing the difference in rotational speed between the roll and a high-speed rotating roll whose surface temperature was set to 78°C. Thereafter, a 10% relaxation treatment was performed in the longitudinal direction at 78° C. by utilizing the speed difference between the high-speed rotating roll and another low-speed rotating roll.
  • Example 1 A uniaxially stretched film roll was obtained in the same manner as in Example 1, except that the relaxation treatment in the width direction was not performed after the lateral stretching in the lateral stretching device.
  • the manufacturing conditions and evaluation results are shown in Table 2.
  • Example 2 A uniaxially stretched film roll was obtained in the same manner as in Example 1, except that a heat treatment at 110° C. and a 10% relaxation treatment in the width direction were performed after the lateral stretching in the lateral stretching device.
  • the manufacturing conditions are shown in Table 2, and the evaluation results are shown in Table 2.
  • Example 3 The polyester raw materials shown in Table 2 were melt-extruded in the same manner as in Example 1 to obtain an unstretched film. Under the conditions shown in Table 3, the unstretched film was preheated to 95°C in a tenter without longitudinal stretching, then stretched 4.5 times in the width direction at 85°C, and then heat-treated at 83°C in the width direction. A 10% relaxation treatment was performed. Next, the uniaxially stretched film of about 40 ⁇ m was wound into a roll while cutting and removing both edges of the film. The properties of the obtained film were evaluated by the method described above. The evaluation results are shown in Table 2.
  • Example 4 The polyester raw materials shown in Table 2 were melt-extruded in the same manner as in Example 1 to obtain an unstretched film. Under the conditions shown in Table 3, the unstretched film was longitudinally stretched 3.6 times at 85°C, preheated to 140°C in a tenter, stretched 5.3 times in the width direction at 110°C, and then stretched at 95°C. Heat treatment and 10% relaxation treatment in the width direction were performed. Next, the uniaxially stretched film of about 40 ⁇ m was wound into a roll while cutting and removing both edges of the film. The properties of the obtained film were evaluated by the method described above. The evaluation results are shown in Table 2.
  • the heat-shrinkable film for laser printing is a stretched film that has undergone a predetermined relaxing process using a predetermined amount of at least one of butanediol, diethylene glycol, and ⁇ -caprolactone, and is a stretched film that has undergone a predetermined relaxing process.
  • the laser printing was free of unevenness, wrinkles, and distortion.
  • Comparative Example 1 the relaxation in the lateral direction was 0% (no relaxation), and in Comparative Example 3, the total amount of long chain molecules butanediol, ⁇ -caprolactone, and diethylene glycol was 1.8 mol%, so Comparative Example 4 Since the stretching ratio in the longitudinal direction, which is not the main shrinkage direction, was set to 3.6, the reduction rate of shrinkage at 80° C. after 10% shrinkage was lower than 11% in all cases, resulting in poor laser printing quality. In Comparative Example 2, the shrinkage rate in the main shrinkage direction before shrinkage did not satisfy the predetermined range, resulting in a film with poor shrinkage finishing properties.
  • the heat-shrinkable polyester film for laser printing of the present invention has no unevenness, wrinkles, or distortion in the laser printing on the product after shrinkage, so it can be used as a label that serves both to protect glass bottles or plastic bottles, and to display the product. It can be widely used for packaging, cap seals, integrated packaging, etc.

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Abstract

Le problème décrit par la présente invention est de fournir un film à base de polyester thermorétractable qui est destiné à l'impression laser et qui ne provoque pas d'irrégularité, de plis ou de déformation par rapport à l'impression laser sur un produit rétracté. La solution selon l'invention porte sur un film à base de polyester thermorétractable pour impression laser qui comprend au moins une couche d'impression laser qui subit un changement de couleur lors de l'irradiation avec un laser et satisfait les conditions (1)-(3) suivantes. (1) Le pourcentage de retrait dans une direction de retrait principale à 80°C est de 30 à 80 %. (2) Un taux de diminution du pourcentage de retrait dans la direction de retrait principale à 80°C, après avoir subi un retrait à 10 % dans la direction de retrait principale dans l'air chaud à 100°C, est de 11 à 30 %. (3) Le taux de transmittance à 355 nm dans le spectre ultraviolet-visible est de 65 à 90 %.
PCT/JP2023/020970 2022-06-13 2023-06-06 Film à base de polyester thermorétractable pour impression laser WO2023243486A1 (fr)

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Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2014012379A (ja) * 2012-07-05 2014-01-23 C I Kasei Co Ltd 熱収縮性ポリエステル系フィルムおよびその製造方法
WO2016152517A1 (fr) * 2015-03-20 2016-09-29 東洋紡株式会社 Film de polyester thermorétractable et matériau d'emballage
JP2016193491A (ja) * 2014-02-04 2016-11-17 東洋紡株式会社 熱収縮性ポリエステル系フィルム
WO2021079868A1 (fr) * 2019-10-25 2021-04-29 東洋紡株式会社 Film imprimable au laser et emballage dans lequel il est utilisé
JP2021138098A (ja) * 2020-03-06 2021-09-16 三菱ケミカル株式会社 熱収縮性積層フィルム

Patent Citations (5)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
JP2014012379A (ja) * 2012-07-05 2014-01-23 C I Kasei Co Ltd 熱収縮性ポリエステル系フィルムおよびその製造方法
JP2016193491A (ja) * 2014-02-04 2016-11-17 東洋紡株式会社 熱収縮性ポリエステル系フィルム
WO2016152517A1 (fr) * 2015-03-20 2016-09-29 東洋紡株式会社 Film de polyester thermorétractable et matériau d'emballage
WO2021079868A1 (fr) * 2019-10-25 2021-04-29 東洋紡株式会社 Film imprimable au laser et emballage dans lequel il est utilisé
JP2021138098A (ja) * 2020-03-06 2021-09-16 三菱ケミカル株式会社 熱収縮性積層フィルム

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