KR-20260065849-A - Method for distinguishing between adhesive and substrate

Abstract

A method for easily distinguishing an adhesive and a substrate from a mixture comprising an adhesive and a substrate is provided. The method for distinguishing an adhesive and a substrate according to an embodiment of the present invention is a method for distinguishing an adhesive and a substrate from a mixture (A) comprising an adhesive, a substrate and a first organic solvent, and performs at least one operation selected from the group consisting of (i), (ii), and (iii) below. (i) A stirring operation of the mixture (A) in a saturated aqueous solution of the first organic solvent. (ii) A stirring operation of the mixture (A) in a mixture of water containing at least one selected from the group consisting of a second organic solvent and a third organic solvent in an amount exceeding saturation. (iii) Immerse the mixture (A) in a third organic solvent, recover the mixture (B) after immersion, and stir the mixture (B) in water.

Inventors

• 고타니 치히로
• 노무라 다카유키
• 야마다 요스케
• 야마모토 아키요시

Assignees

• 닛토덴코 가부시키가이샤

Dates

Publication Date

20260511

Application Date

20240821

Priority Date

20230905

Claims (7)

1. A method for distinguishing the adhesive and the substrate from a mixture (A) comprising the adhesive, the substrate and the first organic solvent, and Performing at least one operation selected from the group consisting of (i), (ii), and (iii) below, Method for distinguishing between adhesive and substrate. (i) A stirring operation of the mixture (A) in a saturated aqueous solution of the first organic solvent. (ii) A stirring operation of the mixture (A) in a mixture of water containing at least one selected from the group consisting of a second organic solvent and a third organic solvent in an amount exceeding saturation. (iii) Immerse the mixture (A) in a third organic solvent, recover the mixture (B) after immersion, and stir the mixture (B) in water.
2. In paragraph 1, A fractionation method in which the first organic solvent is an organic solvent having an HSP value of 10 to 45.
3. In paragraph 1, A fractionation method wherein the second organic solvent is an organic solvent having an HSP value of 10 to 45 and a solubility in water exceeding 10 g/L and less than or equal to 500 g/L at 20°C.
4. In paragraph 1, A fractionation method in which the above-mentioned third organic solvent is an organic solvent having an HSP value of 10 to 45 and a solubility in water of 10 g/L or less at 20°C.
5. In paragraph 1, A separation method that involves settling after the above stirring.
6. In paragraph 1, A method of differentiation in which the above adhesive is an adhesive included in an adhesive tape.
7. In paragraph 1, A method of differentiation in which the above description is a material included in an adhesive tape.

Description

Method for distinguishing between adhesive and substrate The present invention relates to a method for distinguishing between an adhesive and a substrate. Adhesive tapes are widely used for attaching labels to articles or packaging materials, baling materials, use in manufacturing processes for electronic or optical components, and for masking purposes. In particular, their use in manufacturing processes for electronic or optical components has increased recently, and a large amount of adhesive tape waste is generated at manufacturing sites. Waste adhesive tape is typically disposed of by incineration or transported to a waste disposal facility. However, from the perspective of reducing the environmental burden and, furthermore, resource circulation, such disposal methods are undesirable. Therefore, it is necessary to minimize the disposal of adhesive tape waste as described above and to reuse resources. As a means of reducing such disposal of adhesive tape, the recycling of adhesive tape materials is considered. Once the technology for recycling adhesive tape materials is established, it is expected to lead to the suppression of CO2 emissions related to fossil resource extraction, for example, and have a significant effect on solving the problem of climate change. Representative materials for adhesive tape include adhesives and substrates. An adhesive tape is typically obtained by dissolving a polymer (sometimes referred to as a base polymer) and additives according to the purpose, such as a crosslinking agent, in a solvent to form an adhesive composition, coating this onto a substrate, and, if necessary, performing heating and drying to carry out a crosslinking reaction, thereby forming an adhesive on the substrate (e.g., Patent Document 1). Where the term "weight" appears in this specification, it may be replaced with "mass," which is the SI unit commonly used to represent weight. In this specification, when "specific gravity" is used, it refers to the commonly accepted meaning of specific gravity, which is the specific gravity when the specific gravity of water is set to 1. A method for distinguishing between an adhesive and a substrate according to an embodiment of the present invention is a method for distinguishing between the adhesive and the substrate from a mixture (A) comprising an adhesive, a substrate, and a first organic solvent. As an adhesive, any suitable adhesive may be used within a range that does not impair the effects of the present invention. The adhesive may be of only one type or two or more types. Representative examples of such adhesives include acrylic adhesives. As for the acrylic adhesive, any suitable acrylic adhesive may be used within a range that does not impair the effects of the present invention. Representative examples of such acrylic adhesives include acrylic adhesives as waste (sometimes referred to as "waste acrylic adhesives"). Examples of waste acrylic adhesives include, for instance, acrylic adhesives contained in acrylic adhesive tapes recovered after use; a mixture containing acrylic adhesives obtained by performing any suitable treatment on acrylic adhesive tapes recovered after use; acrylic adhesives that remain on a substrate when the acrylic adhesive tape is peeled off from a substrate to which the acrylic adhesive tape is attached; and acrylic adhesives attached to an acrylic adhesive manufacturing device. As for the material, any suitable material may be adopted within a range that does not impair the effects of the present invention. The material may be of only one type or two or more types. Representative examples of such a material include a material included in an adhesive tape. As for the substrate, any suitable substrate may be adopted within a range that does not impair the effects of the present invention. Representative examples of such substrates include a substrate as a waste material (sometimes referred to as "waste material"). Examples of waste materials include a substrate contained in adhesive tape recovered after use, or a mixture comprising a substrate obtained by performing any suitable treatment on adhesive tape recovered after use. As for the material of the base, any suitable material may be adopted within a range that does not impair the effects of the present invention. Representative examples of such a material of the base include resin materials. Examples of resin materials used as the material for the base include, for instance, acrylic resins such as polyimide (PI), polyetheretherketone (PEEK), polyethylene terephthalate (PET), polyethylene naphthalate (PEN), polybutylene terephthalate (PBT), and polymethyl methacrylate (PMMA), polycarbonate, triacetylcellulose (TAC), polysulfone, polyarylate, polyethylene (PE), polypropylene (PP), ethylene-propylene copolymer, ethylene-vinyl acetate copolymer (EVA), polyamide (nylon), fully aromatic polyamide (aramid), polyvinyl chloride (PVC), polyvinyl acetate, polyphenylene sulfide (PPS), flu