JP-2026074463-A - Recycled resin compositions, resin molded products, resin housings, and electronic devices

Abstract

[Problem] The problem addressed by the present invention is to provide a recycled resin composition, resin molded product, resin housing, and electronic device that are substantially free of harmful substances, have high impact strength, and are excellent in flame retardancy. [Solution] A recycled resin composition comprising a PCR material containing polycarbonate and a core-shell type impact modifier, wherein the core-shell type impact modifier contains silicone rubber, and the fluororesin content in the recycled resin composition is less than 1000 ppm. [Selection Diagram] None

Inventors

• ▲崎▼村 友男
• 間簔 雅

Assignees

• コニカミノルタ株式会社

Dates

Publication Date

20260507

Application Date

20241021

Claims (7)

1. A recycled resin composition containing a PCR material containing polycarbonate and a core-shell type impact modifier, The aforementioned core-shell type impact modifier contains silicone rubber, A recycled resin composition characterized in that the fluororesin content in the recycled resin composition is less than 1,000 ppm.
2. The recycled resin composition according to claim 1, characterized in that the core of the core-shell type impact modifier is a silicone-acrylic composite rubber, and the shell is composed of a resin having structural units derived from methyl methacrylate.
3. The recycled resin composition according to claim 1, characterized in that the total content of the PCR material containing the polycarbonate and the core-shell type impact modifier in the recycled resin composition is 50% by mass or more, and the content ratio of the PCR material containing the polycarbonate and the core-shell type impact modifier is in the range of 88:12 to 96:4.
4. The recycled resin composition according to claim 1, characterized in that the total content of chlorine and bromine in the recycled resin composition is less than 1,000 ppm.
5. A resin molded article characterized by being composed of a recycled resin composition according to any one of claims 1 to 4.
6. A resin housing characterized by including the resin molded product described in claim 5.
7. An electronic device characterized by comprising a resin housing as described in claim 6.

Description

This invention relates to recycled resin compositions, resin molded articles, resin housings, and electronic devices. More specifically, it relates to recycled resin compositions, resin molded articles, resin housings, and electronic devices that possess high impact strength and excellent flame retardancy. In recent years, PFAS regulations concerning resin molded products and other similar items have become stricter. Many of these products contain harmful substances such as fluororesins like polytetrafluoroethylene (PTFE). Therefore, there is a requirement to minimize the amount of harmful substances such as fluororesins in such products. Hereafter, "polytetrafluoroethylene" will be abbreviated as "PTFE." Here, resin molded products are required to be flame-retardant, and some are required to conform to the V-0 standard set by UL (Underwriters Laboratories) in the United States, which is used in the evaluation of this flame retardancy. Hereafter, this standard will be referred to as the "V-0 standard." Resin molded products that are required to comply with V-0 standards often use flame retardants and drip inhibitors during manufacturing to ensure flame retardancy, considering the impact on human health and environmental protection. Drip inhibitors typically use PTFE or its processed products to ensure flame retardancy, and as a result, these resin molded products often contain a significant amount of harmful substances such as fluororesins. For example, for electronic device casings that require excellent performance in both flame retardancy and impact strength, technologies such as those disclosed in Patent Document 1 have been disclosed. Furthermore, as disclosed in Patent Document 2, a technology for preventing degradation from initial performance has been disclosed for resin compositions made using PCR material containing polycarbonate as a raw material. However, there is still room for improvement in these technologies. Japanese Patent Application Publication No. 11-21441Japanese Patent Publication No. 2000-103952 The present invention, its components, and embodiments for carrying out the present invention will be described in detail below. In this application, "~" is used to mean that the numerical values before and after it include the lower and upper limits, respectively. The advantages and features provided by one or more embodiments of the present invention will be better understood from the following detailed description and accompanying drawings, which are for illustrative purposes only. Therefore, they are not intended to define any limitations of the invention. 1. Recycled Resin Composition The recycled resin composition of the present invention is characterized by containing a PCR material containing polycarbonate and a core-shell type impact modifier, wherein the core-shell type impact modifier contains silicone rubber and the fluororesin content is less than 1000 ppm. (1.1) Contents (PCR material containing polycarbonate) The "PCR material containing polycarbonate" according to the present invention is a raw material for the recycled resin composition of the present invention, and is a market-recovered resin recovered from molded products using polycarbonate as a base material. It should be noted that such market-recovered resins typically contain resins other than polycarbonate, and strictly speaking, PCR materials containing polycarbonate also include substances that are not resins. There are no particular restrictions on the polycarbonate content in the PCR material according to the present invention; it is sufficient as long as polycarbonate is the main component. Here, "virgin polycarbonate" as used herein refers to polycarbonate material before it is molded into an article, and is not a recycled resin from the market. Virgin polycarbonate itself is usually sold as pellets consisting solely of virgin polycarbonate. Furthermore, pellets of virgin polycarbonate resin compositions with added additives such as colorants, antioxidants, and flame retardants are also sold. These pellets are fed into a molding machine to produce molded resin articles. There are no particular restrictions on the polycarbonate content in the virgin polycarbonate resin composition; it is sufficient as long as polycarbonate is the main component. Virgin polycarbonate, while possessing excellent impact resistance in its initial state, is a material that degrades rapidly due to its poor fluidity and susceptibility to hydrolysis. Furthermore, while virgin polycarbonate alone can exhibit flame retardancy of approximately V-2, achieving V-0 flame retardancy requires the inclusion of PTFE containing harmful substances or other flame retardants. However, the recycled resin composition of the present invention, even without containing virgin polycarbonate, can improve flame retardancy to V-0 by including a polycarbonate-containing PCR material, without the need for the aforementioned PTFE or flame retardants. Furthermore,