Classifications

• • B—PERFORMING OPERATIONS; TRANSPORTING
  • B29—WORKING OF PLASTICS; WORKING OF SUBSTANCES IN A PLASTIC STATE IN GENERAL
  • B29B—PREPARATION OR PRETREATMENT OF THE MATERIAL TO BE SHAPED; MAKING GRANULES OR PREFORMS; RECOVERY OF PLASTICS OR OTHER CONSTITUENTS OF WASTE MATERIAL CONTAINING PLASTICS
  • B29B17/00—Recovery of plastics or other constituents of waste material containing plastics
  • B29B17/02—Separating plastics from other materials
• • C—CHEMISTRY; METALLURGY
  • C09—DYES; PAINTS; POLISHES; NATURAL RESINS; ADHESIVES; COMPOSITIONS NOT OTHERWISE PROVIDED FOR; APPLICATIONS OF MATERIALS NOT OTHERWISE PROVIDED FOR
  • C09D—COATING COMPOSITIONS, e.g. PAINTS, VARNISHES OR LACQUERS; FILLING PASTES; CHEMICAL PAINT OR INK REMOVERS; INKS; CORRECTING FLUIDS; WOODSTAINS; PASTES OR SOLIDS FOR COLOURING OR PRINTING; USE OF MATERIALS THEREFOR
  • C09D9/00—Chemical paint or ink removers
• • Y—GENERAL TAGGING OF NEW TECHNOLOGICAL DEVELOPMENTS; GENERAL TAGGING OF CROSS-SECTIONAL TECHNOLOGIES SPANNING OVER SEVERAL SECTIONS OF THE IPC; TECHNICAL SUBJECTS COVERED BY FORMER USPC CROSS-REFERENCE ART COLLECTIONS [XRACs] AND DIGESTS
  • Y02—TECHNOLOGIES OR APPLICATIONS FOR MITIGATION OR ADAPTATION AGAINST CLIMATE CHANGE
  • Y02W—CLIMATE CHANGE MITIGATION TECHNOLOGIES RELATED TO WASTEWATER TREATMENT OR WASTE MANAGEMENT
  • Y02W30/00—Technologies for solid waste management
  • Y02W30/50—Reuse, recycling or recovery technologies
  • Y02W30/62—Plastics recycling; Rubber recycling

Definitions

• Patent Document 1 One example of technology in this field is described in Patent Document 1.
• Patent Document 1 describes a method for separating and recovering laminated films, which is aimed at providing a method for easily separating laminated films laminated with a reactive adhesive present in plastic composite waste into single-layer films, and which is characterized by having step 1 of immersing the laminated film laminated with an adhesive in a morpholine solution having a morpholine concentration of 50% by mass or more while heating and stirring the laminated film at 20 to 90°C or subjecting it to ultrasonic vibration, and step 2 of recovering the single-layer films of each separated layer.
• the present invention relates to a method for producing a treatment liquid for peeling a laminated resin film, comprising the steps of: [20] A method for producing recycled resin, comprising a peeling step of peeling at least a part of a laminate resin film by the method for peeling a laminate resin film according to any one of [9] to [18].
• the content of potassium hydroxide in the laminate resin film peeling treatment liquid when the entire laminate resin film peeling treatment liquid is taken as 100 mass%, is preferably 0.5 mass% or more, more preferably 1 mass% or more, even more preferably 3 mass% or more, and even more preferably 5 mass% or more, from the viewpoint of further improving the peelability of the laminate resin film, and is preferably 18 mass% or less, more preferably 15 mass% or less, and even more preferably 12 mass% or less, from the viewpoint of further improving the solubility of potassium hydroxide and alcohol.
• the content of the amide-based solvent in the laminate resin film peeling treatment liquid is preferably 1 mass % or more, more preferably 5 mass % or more, even more preferably 10 mass % or more, and even more preferably 20 mass % or more, and is preferably 60 mass % or less, more preferably 55 mass % or less, and even more preferably 50 mass % or less, when the entire laminate resin film peeling treatment liquid is taken as 100 mass %.
• the content of the amide-based solvent equal to or more than the lower limit, the peelability of the printed layer of the laminate resin film described below can be further improved.
• the solubility of potassium hydroxide in the laminate resin film peeling treatment liquid can be further improved, and the peelability of the laminate resin film can be further improved.
• the amide-based solvent may be any compound having an amide bond in the molecule, and examples thereof include ⁇ -alkoxy-N-substituted propanamide, N-methylpyrrolidone (NMP) (N-methyl-2-pyrrolidone), dimethylformamide (DMF), diethylformamide (DEF), and the like.
• NMP N-methylpyrrolidone
• DMF dimethylformamide
• DEF diethylformamide
• the method for producing the treatment liquid for peeling off a laminated resin film of this embodiment preferably includes a step of preparing a mixed solution of potassium hydroxide and an alcohol, and a step of adding an amide solvent to the obtained mixed solution.
• the amide-based solvent is dissolved after potassium hydroxide is sufficiently dissolved in the alcohol, and therefore the solubilities of both the potassium hydroxide and the amide-based solvent can be further improved.
• the laminated resin film peeling treatment liquid of this embodiment contains potassium hydroxide, alcohol, and an amide-based solvent, in the peeling step of the laminated resin film peeling method, peeling of the base material layer and adhesive layer and peeling of the printed layer (deinking) in the laminated resin film can be performed simultaneously.
• the adhesive layer of the laminated resin film can be effectively dissolved by the synergistic effect of potassium hydroxide, alcohol, and amide-based solvent in the laminated resin film peeling treatment liquid, and as a result, the base material layer and the like that were adhered by the adhesive layer can be peeled off.
• This peeling can expose the printed layer that was in the inner layer of the laminated structure of the laminated resin film, and the printed layer can be peeled off (deinked). Therefore, the obtained recycled resin can be colorless (white).
• "colorless (white)" means "colorless or white”.
• the printing ink used in the printing layer may be a known one.
• Typical binder resins for printing inks include one or more selected from the group consisting of cellulose resins such as nitrocellulose, urethane resins, polyamide resins, vinyl chloride/vinyl acetate copolymers, rosin resins and modified products thereof, ketone resins, polyester resins, and (meth)acrylic resins.
• the printed layer may or may not contain a hardener in the ink depending on the application of the laminated resin film.
• the laminated resin film peeling treatment liquid of this embodiment can peel (deink) the printed layer regardless of whether the ink contains a hardener or not.
• the polyol compound is not particularly limited, but examples thereof include polyols having a number of functional groups of preferably 2 to 6, more preferably 2 to 4, a number average molecular weight of preferably 200 to 200,000, more preferably 300 to 100,000, and even more preferably 300 to 50,000, and an acid value of preferably 0 to 280 mgKOH/g, more preferably 0 to 100 mgKOH/g, and even more preferably 0 to 50 mgKOH/g.
• the total thickness of the laminated resin film of the present embodiment is preferably 20 ⁇ m or more, more preferably 30 ⁇ m or more, and even more preferably 40 ⁇ m or more, and is preferably 200 ⁇ m or less, and more preferably 150 ⁇ m or less.
• the thickness of the substrate layer in this embodiment is preferably 10 ⁇ m or more, more preferably 20 ⁇ m or more, and is preferably 150 ⁇ m or less, more preferably 100 ⁇ m or less.
• the thickness of the adhesive layer in this embodiment is preferably 1 ⁇ m or more, more preferably 2 ⁇ m or more, preferably 3 ⁇ m or more, and is preferably 10 ⁇ m or less, more preferably 5 ⁇ m or less.
• Laminated films 1 to 4 were prepared according to the following procedure.
• ⁇ Printing method> The above printing ink was printed on an OPP film using a gravure printing machine. When a hardener was used, the hardener was mixed with the ink before printing on the OPP film.
• laminate resin film 1 OPP film 1 was changed to OPP film 2 with a printed layer (with hardener), and an adhesive (a mixture of adhesive 1 and adhesive 2) was applied to the surface of the printed layer side, but the film was produced in the same manner as laminate resin film 1, thereby obtaining laminate resin film 3 having a structure of OPP (with printed layer (with hardener))/adhesive layer/CPP.
• laminate resin film 4 of OPP (with printed layer (with curing agent))/adhesive layer/VMCPP was obtained in the same manner as laminated resin film 3, except that the CPP film in laminated resin film 3 was replaced with a VMCPP film.
• laminate resin film 5 (Laminated Resin Film 5) The above inks 1 to 6 (without hardener) were printed on top of each other in the order of the ink numbers by the above ⁇ Printing method> to obtain an OPP film 3 with a printed layer (without hardener).
• OPP film 1 was changed to OPP film 3 with a printed layer (without curing agent), and an adhesive (a mixture of adhesive 1 and adhesive 2) was applied to the surface of the printed layer side, but the film was produced in the same manner as laminate resin film 1, thereby obtaining laminate resin film 5 having a structure of OPP (with printed layer (without curing agent))/adhesive layer/CPP.
• the obtained laminated resin films 1 and 3 were cut into pieces of 10 mm x 10 mm size with a cutter according to the small piece cutting conditions in Table 1.
• the cut pieces had a shape close to a square with one side measuring 10 mm.
• each of the laminated resin films 2 to 4 was subjected to a crushing machine (SRH3-360TRFS, manufactured by HORAI CORPORATION) using a screen having a mesh diameter of 6 mm ⁇ or 10 mm ⁇ , and small pieces passing through each screen were collected.
• the shapes of the crushed small pieces were random.
• the laminated resin films 1 to 4 cut into small pieces were treated with the laminated film peeling treatment liquid of each example.
• 0.1 g of the laminated resin film and 20 g of the laminated film peeling treatment liquid were placed in a glass container, and the sealed glass container was heated to 50°C.
• a magnetic stirrer with a heater was used to stir with a stirrer tip.
• ultrasonic treatment was performed, the temperature was maintained at 50°C in an ultrasonic cleaner with a heating function (As One Corporation, model number: US-2), and ultrasonic treatment was performed at 38 kHz. In both cases, stirring or ultrasonic treatment was performed while maintaining the temperature at 50°C, and the peelability was evaluated after 2 hours, 6 hours, and 12 hours.

Landscapes

• Engineering & Computer Science (AREA)
• Chemical & Material Sciences (AREA)
• Environmental & Geological Engineering (AREA)
• Mechanical Engineering (AREA)
• Chemical Kinetics & Catalysis (AREA)
• General Chemical & Material Sciences (AREA)
• Life Sciences & Earth Sciences (AREA)
• Materials Engineering (AREA)
• Wood Science & Technology (AREA)
• Organic Chemistry (AREA)
• Separation, Recovery Or Treatment Of Waste Materials Containing Plastics (AREA)

Priority Applications (1)

Applications Claiming Priority (2)

Publications (1)

Family

ID=91717521

Family Applications (1)

Country Status (2)

Citations (7)

• 2023
  • 2023-12-08 JP JP2024567404A patent/JPWO2024142859A1/ja active Pending
  • 2023-12-08 WO PCT/JP2023/044090 patent/WO2024142859A1/ja active Application Filing

Patent Citations (7)

Also Published As

Similar Documents

Legal Events