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EP-3733752-B1 - THERMOPLASTIC RESIN COMPOSITION AND MOLDED PRODUCT MANUFACTURED THEREFROM

EP3733752B1EP 3733752 B1EP3733752 B1EP 3733752B1EP-3733752-B1

Inventors

  • BAE, SEUNG YONG
  • KIM, YOEN KYOUNG
  • KIM, JU SUNG
  • YANG, CHEON SEOK

Dates

Publication Date
20260506
Application Date
20181218

Claims (9)

  1. A thermoplastic resin composition comprising: 100 parts by weight of a thermoplastic resin comprising at least one of a polyamide resin and a polyester resin; and 1 part by weight to 5 parts by weight of zinc oxide, wherein the zinc oxide has an average particle diameter (D50) of 0.8 µm to 3 µm, as measured using a particle size analyzer; a peak intensity ratio (B/A) of 0.01 to 1.0, where A indicates a peak in the wavelength range of 370 nm to 390 nm and B indicates a peak in the wavelength range of 450 nm to 600 nm in photoluminescence measurement; a peak position degree (2θ) in the range of 35° to 37°; and a crystallite size of 1,000 Å to 2,000 Å in X-ray diffraction (XRD) analysis (measured using a high-resolution X-ray diffractometer (PRO-MRD, X'pert Inc.), as calculated by Equation 1: Crystallite size D = Kλ β cos θ where K is a shape factor, λ is an X-ray wavelength, β is an FWHM (full width at half maximum of a diffraction peak) value (degree) of an X-ray diffraction peak, and θ is a peak position degree, and wherein the polyamide resin comprises an aliphatic polyamide resin, a semi-aromatic polyamide resin, or a combination thereof and the polyester resin comprises at least one of polyethylene terephthalate, polybutylene terephthalate, polyethylene naphthalate, polytrimethylene terephthalate, and polycyclohexylene terephthalate.
  2. The thermoplastic resin composition according to claim 1, wherein the zinc oxide has a peak intensity ratio (B/A) of 0.1 to 1.0, where A indicates a peak in the wavelength range of 370 nm to 390 nm and B indicates a peak in the wavelength range of 450 nm to 600 nm in photoluminescence measurement.
  3. The thermoplastic resin composition according to claim 1 or 2, wherein the zinc oxide has an average particle diameter (D50) of 1 µm to 5 µm, as measured using a particle size analyzer.
  4. The thermoplastic resin composition according to any one of claims 1 to 3, wherein the zinc oxide has a BET specific surface area of 10 m 2 /g or less, as measured by a nitrogen gas adsorption method using a BET analyzer.
  5. The thermoplastic resin composition according to any one of claims 1 to 4, wherein the zinc oxide has a BET specific surface area of 1 m 2 /g to 7 m 2 /g, as measured by a nitrogen gas adsorption method using a BET analyzer.
  6. The thermoplastic resin composition according to any one of claims 1 to 5, wherein the thermoplastic resin composition has a color variation (ΔE) of 2 to 7, as calculated according to Equation 2 based on initial color values (L 0 *, a 0 *, b 0 *) measured on an injection-molded specimen having a size of 50 mm×90 mm×2.5 mm using a colorimeter and color values (L 1 *, a 1 *, b 1 *) of the specimen measured in the same manner as above after testing for 1,500 hours in accordance with ASTM D4459, Color variation ΔE = Δ L * 2 + Δ a * 2 + Δ b * 2 where ΔL* is a difference (L 1 *-L 0 *) between L* values before and after testing, Δa* is a difference (a 1 *-a 0 *) between a* values before and after testing, and Δb* is a difference (b 1 *-b 0 *) between b* values before and after testing.
  7. The thermoplastic resin composition according to any one of claims 1 to 6, wherein the thermoplastic resin composition has an antibacterial activity of 2 to 7 against each of Staphylococcus aureus and Escherichia coli, as calculated according to Equation 3 after inoculation of 5 cm×5 cm specimens with Staphylococcus aureus and Escherichia coli, respectively, and culturing under conditions of 35°C and 90% RH for 24 hours in accordance with JIS Z 2801, Antibacterial activity = log M 1 / M 2 where M1 is the number of bacteria as measured on a blank specimen after culturing for 24 hours and M2 is the number of bacteria as measured on each of the specimens of the thermoplastic resin composition after culturing for 24 hours.
  8. A molded product formed of the thermoplastic resin composition according to any one of claims 1 to 7.
  9. The molded product according to claim 8, wherein the molded product comprises synthetic fibers.

Description

[Technical Field] The present invention relates to a thermoplastic resin composition and a molded product manufactured therefrom. More particularly, the present invention relates to a thermoplastic resin composition which has good weather resistance, antibacterial properties, and mechanical properties, and a molded product manufactured therefrom. [Background Art] Recently, with increasing interest in personal health and hygiene and increasing income level, there is increasing demand for thermoplastic resin products having antibacterial and hygienic functions. Accordingly, there is an increasing number of thermoplastic resin products subjected to antibacterial treatment to remove or inhibit bacterial growth on surfaces of household goods and electronic products. Therefore, development of a functional antibacterial material having stability and reliability (an antibacterial thermoplastic resin composition) is a very important challenge. In addition, with increasing interest in personal hygiene and beauty, there is increasing demand for oral hygiene products and beauty equipment, and the adoption of antibacterial materials, such as brushes with antibacterial bristles (antibacterial fiber) is increasing in the art. In order to prepare such an antibacterial thermoplastic resin composition, it is necessary to add antibacterial agents. Such antibacterial agents may be divided into organic antibacterial agents and inorganic antibacterial agents. Organic antibacterial agents are sometimes toxic to humans, are effective only against certain bacteria, and are likely to decompose and lose antibacterial properties upon processing at high temperature, despite being relatively inexpensive and providing good antimicrobial effects even in small amounts. In addition, since the organic antibacterial agents can cause discoloration after processing and cannot have long-term antibacterial persistence due to dissolution-related problems, the range of organic antibacterial agents applicable to an antibacterial thermoplastic resin composition is extremely limited. Inorganic antibacterial agents are antibacterial agents containing metal components, such as silver (Ag) and copper (Cu), and are widely used in preparation of antibacterial thermoplastic resin compositions (antibacterial resins) due to good thermal stability thereof. However, since the inorganic antibacterial agents need to be used in large amounts due to lower antibacterial activity than the organic antibacterial agents and have disadvantages of relatively high price, difficulty in uniform dispersion upon processing, and discoloration due to the metal components, the inorganic antibacterial agents are used in a limited range of applications. Therefore, there is a need for a thermoplastic resin composition which has good properties in terms of weather resistance (discoloration resistance), antibacterial effects, and antibacterial persistence while providing antifungal properties. The background technique of the present invention is disclosed in Korean Patent No. 10-0696385 and thefollowing documents: EP3315546A1 (published on May 2, 2018) discloses a thermoplastic resin composition which exhibits good properties in terms of weather resistance and antibacterial resistance, said composition comprising a thermoplastic resin (100 parts by weight) comprising among others a polyamide resin and a polyester resin and zinc oxide (0.5-30 parts by weight) having a peak intensity ratio (B/A) of 0.1-10 wherein A indicates a peak in the wavelength range of 370 nm to 390 nm and B indicates a peak in the wavelength range of 450 nm to 600 nm in photoluminescence measurement; a peak position degree (2θ) in the range of 35° to 37°; and a crystallite size of 1,000 Å to 2,000 Å in analysis of X-ray diffraction (XRD), as calculated by Equation 1: CrystallitesizeD=Kλβcosθ wherein, K is a shape factor, λ is an X-ray wavelength, β is an FWHM value (degree) of an X-ray diffraction peak, and θ is a peak position degree. EP3560902A1 (published on October 30, 2019) discloses a composition for artificial marble comprising a binder resin (100 parts by weight) which includes an acrylic resin and an unsaturated polyester resin, an inorganic filler (100-300 parts by weight) and zinc oxide (1-10 parts by weight) having a peak intensity ratio (B/A, as defined above) of 0.01-1, a peak position degree (2θ) in the range of 35° to 37°; and a crystallite size of 1,000 Å to 2,000 Å in analysis of X-ray diffraction (XRD), as calculated by above-mentioned Equation 1. JPH10251444A discloses a resin composition having antibacterial properties comprising a polymer material (100 parts by weight), a phosphoric ester compound (0.001-10 parts by weight) and a zinc oxide (0.001 to 10 parts by weight). Prasanna VL, "Insight into the mechanism of antibacterial activity of ZnO: surface defects mediated reactive oxygen species even in the dark", Langmuir, 2015, pages 9155-9162, has evidenced that the surface charge density of