Silver-loaded glass antibacterial agent, transparent antibacterial resin product thereof, and article manufactured therefrom

Abstract

The present invention relates to the field of antibacterial materials. Specifically, provided are a silver-loaded glass antibacterial agent, a transparent antibacterial resin product thereof, and an article manufactured therefrom. The silver-loaded glass antibacterial agent comprises, in terms of oxides and based on the total molar amount of each component: 11-15 mol % P2O5, 25-35 mol % B2O3, and 50-60 mol % MgO; and comprises, in percentage by weight: 0.1-3 wt% Ag2O, 0.003-0.05 wt% Co2O3, and 0.01-0.5 wt% SiO2; wherein the antibacterial transparent resin product and the manufactured article contain the silver-loaded glass antibacterial agent described above, and have a silver migration concentration lower than 5 ppb and a haze increase value less than 5%.

Description

A silver-loaded glass antibacterial agent and its transparent antibacterial resin product and products Technical Field

[0001] The present invention relates to the field of antibacterial materials, in particular to a silver-loaded glass antibacterial agent and a transparent antibacterial resin product and articles thereof. Background Art

[0002] In recent years, areas related to microbiology and human health, such as disease prevention, public health, and environmental safety, have received significant attention. As people's living standards continue to improve, the demand for highly transparent products with antimicrobial properties is growing. Existing technologies primarily achieve this by adding organic antimicrobial and antifungal agents and glass antimicrobial agents. However, organic antimicrobial and antifungal agents have poor safety and low temperature resistance, making them an unsuitable antimicrobial solution for transparent antimicrobial polymers. Meanwhile, common silver-loaded glass antimicrobial agents offer better transparency than zinc-loaded glass antimicrobial agents. However, their transparency is less than ideal when applied to transparent polymers. Furthermore, silver ions can easily discolor when processing temperatures exceed 260-280°C and when benzene rings and carbon-carbon double bonds are present in the polymer.

[0003] Patent CN200410007612.X: Provides an antimicrobial glass composition comprising 0.1-5.0 wt% Ag2O, 30-60 mol% P2O5, 1-15 mol% of one or more compounds selected from K2O, Na2O, and Li2O, 35-55 mol% of one or more compounds selected from MgO, CaO, and ZnO, and 0.01-3 mol% of one or more compounds selected from La2O3 and Y2O3. The present inventors discovered that when the molar content of P2O5 in the antimicrobial glass composition exceeds 40%, or the molar content of alkaline earth metal oxides is less than 50%, or when La2O3 and Y2O3 are present, the haze of the corresponding products significantly increases when applied to polyester and polycarbonate products, exceeding 20%.

[0004] Patent CN201210310233.2: The antimicrobial glass composition comprises the following components, by weight percentage: ZnO 50-60wt%, preferably 50-55wt%; Ag2O 0-0.09wt%, preferably 0.01-0.05wt%. It may also include P2O5 30-40wt%, preferably 35-40wt%; and Na2O or K2O 6-18wt%, preferably 8-10wt%. When applied to polyester and polycarbonate products, this glass antimicrobial agent significantly increases the haze of the resulting products, exceeding 40%.

[0005] Patent CN1202034C: A phosphate glass comprising, based on 100% by weight, 0.2-5% Ag2O, 1-50% ZnO, 0.1-15% CaO, 0.1-15% B2O3, and 30-80% P2O5, with a ZnO / CaO weight ratio of 1.1-15. This glass antimicrobial agent significantly increases the haze of polyester and polycarbonate products when applied to these products.

[0006] Patent CN1323588C: A borosilicate glass antibacterial agent, which comprises 0.1-2wt% Ag2O, 40.5-49wt% ZnO, 6-9.5wt% SiO2, 30.5-39.5wt% B2O3, 2-10wt% rare earth metal oxides, 6-7.5wt% Na2O, and 0.01-5wt% CeO 2。 When the glass antibacterial agent is applied to polyester and polycarbonate, the haze of the corresponding products will also increase significantly.

[0007] In view of this, the present invention is proposed. Technical issues

[0008] Existing technologies mainly achieve this by adding organic antibacterial and mildew-proofing agents and glass antibacterial agents. However, organic antibacterial and mildew-proofing agents have poor safety and low temperature resistance, and are not the optimal antibacterial solution for transparent antibacterial polymer materials. At the same time, general silver-loaded glass antibacterial agents have better transparency than zinc-loaded glass antibacterial agents, but their transparency when applied to transparent polymer materials is not ideal. Moreover, when the processing temperature exceeds 260-280°C and benzene rings and carbon-carbon double bonds exist in the polymer material, it is easy to cause silver ions to discolor. Technical Solutions

[0009] The present invention provides a silver-loaded glass antibacterial agent. Based on the total molar number of each component, calculated as oxides, the silver-loaded glass antibacterial agent contains: 11-15 mol% P2O5, 25-35 mol% B2O3, 50-60 mol% MgO; wherein the weight percentage of the silver-loaded glass antibacterial agent is 0.1-3 wt% Ag2O, 0.003-0.05 wt% Co2O3, and 0.01-0.5 wt% SiO2.

[0010] As with the above-mentioned glass antibacterial agent composition, as arbitrary components, CeO2, CaO, CuO, ZnO, Al2O3, Na2O, V2O5 and other components and their compositions can also be added in a specified amount of 0.0001-5wt% by weight within the scope of the purpose of the present invention.

[0011] In the present invention, the content of P2O5 is preferably 11-15 mol%, and the content of B2O3 is 25-35 mol%. They are the main components of the glass network structure former (the molar ratio of P2O5 to B2O3 is preferably 1:1.5-1:3, more preferably 1:2 as the glass network structure former). The present invention has found through experiments that in order to obtain a more stable P2O5 5 and B2O 3 As the primary network former, the glass must contain an increased amount of B2O3 within its structure. Increasing the proportion of BO3 and BO4 structural units within the glass improves network connectivity, making the glass structure more stable. Furthermore, the borate network inhibits the hydrolysis and dissolution of the phosphate network. Furthermore, increasing the amount of B2O3 lowers the melting point and viscosity of the glass, facilitating its formation. The increased stability of phosphoborate glass helps suppress discoloration caused by silver ions during preparation and application. However, when B2O3 is present, the glass is more stable than the phosphate network. 3 When the molar content of P2O5 is further increased, the stability of the glass tends to decrease. When the molar ratio of P2O5 to B2O3 exceeds 1:1.5, the silver-loaded glass antibacterial agent is easily discolored when applied to polymer materials. When the molar ratio of P2O5 to B2O3 is lower than 1:3, the silver-loaded glass antibacterial agent is easy to discolor. When the content of P2O5 in the present invention is lower than 11 mol%, B2O3 3 When the content of P2O5 is lower than 25mol%, it is not easy to vitrify, and the fired glass is easy to precipitate elemental silver. When the content of P2O5 is further lower than 8mol% or B2O 3 When the content of P2O5 is higher than 15mol%, B2O 3 When the content of P2O5 is higher than 35 mol%, the stability of the glass will decrease and the water resistance will deteriorate. When the content of P2O5 is further higher than 20 mol% or the content of B2O3 is further higher than 40 mol%, the stability of the glass will be significantly reduced and the water resistance will be significantly deteriorated.

[0012] The present inventors discovered that adding 0.01-0.5 wt% SiO2 to the primary network formers of glass can further enhance glass stability and transparency. However, exceeding 0.5 wt% SiO2 reduces the amount of non-bridging oxygen, further reducing silver ions to elemental silver during glass preparation, and ultimately causing discoloration of the glass.

[0013] In the present invention, the MgO content is preferably 50-60 mol%. In phosphoborate glass, MgO is an important network modifier, and its content significantly affects the stability of the glass. When the MgO content is less than 50 mol%, the glass stability decreases. When the MgO content is less than 40 mol%, the number of non-bridging oxygen atoms in the glass network structure is relatively high, significantly reducing the glass's stability and hydrolysis resistance. When the MgO content exceeds 60 mol%, the melting temperature of the glass increases, which can easily lead to crystallization. When the MgO content exceeds 65 mol%, the melting temperature of the glass increases significantly, making processing more difficult. It also makes the glass more susceptible to crystallization, impairing its transparency and homogeneity. Although zinc oxide and calcium oxide can form a synergistic effect with magnesium oxide, which may be beneficial to structural stability and improve antibacterial properties, and the selection of magnesium oxide will also significantly increase the melting temperature of the glass, compared with magnesium oxide, the Ca-O and Zn-O bonds formed by calcium oxide and zinc oxide in the glass are weaker, the chemical stability is lower, and it is more prone to crystallization, its transparency will decrease, and MgO will have a greater effect on regulating the refractive index of the glass. Therefore, the present invention selects MgO as the network modifier of the glass.

[0014] The addition of Co2O3 in the present invention can regulate the glass's absorption of visible and infrared light, and allows cobalt ions to enter the glass network as network modifiers, thereby improving the glass's acid and alkali resistance, improving the stability of the glass in different application scenarios, further suppressing the discoloration problem of the glass during application, and improving the glass's light transmittance and transparency. Cobalt oxide within the concentration range defined by the present invention exhibits a blue hue that is difficult to detect with the naked eye. When applied to polymer materials, it is more comfortable for the human eye and can neutralize the yellow color caused by possible discoloration of silver ions, thereby improving the discoloration resistance and transparency of silver-loaded glass antibacterial materials. However, when the content of cobalt oxide exceeds 0.05%, there will be obvious color development, and the water resistance of the glass will decrease.

[0015] In the present invention, the Ag2O content is preferably 0.1 to 3 wt%. When the Ag2O content is lower than 0.1 wt%, the antibacterial performance is unstable. When the Ag2O content exceeds 3 wt%, the antibacterial glass obtained is prone to discoloration during preparation and application.

[0016] The present invention does not incorporate alkali metal oxides. The addition of alkali metal oxides can reduce the chemical stability of phosphoborate glass, particularly the water resistance of silver-loaded glass, making silver ions more susceptible to discoloration in extreme applications. According to Appendix A of GB / T 17219-1998, Safety Assessment Standard for Drinking Water Transmission and Distribution Equipment and Protective Materials, even 0.1 mol% of alkali metal oxides added to the silver-loaded glass antimicrobial agent will result in a silver ion concentration exceeding 5 ppb.

[0017] The present invention does not add CuO because the addition of more than one thousandth of copper oxide may cause a relatively obvious color change. In addition, the addition of excessive copper oxide will cause the glass to become opaque and cause the breakage of the main network of P~O~P and B~O~B bonds in the glass, thereby reducing the water resistance of the glass.

[0018] The present invention does not add Al2O3. Even though the addition of alumina can further improve the stability of the glass structure, the addition of alumina will cause the glass melting temperature to further increase, which is not conducive to glass melting. At the same time, the addition of alumina will cause the light transmittance of the glass to decrease and the refractive index of the glass to increase. As a result, when the silver-loaded glass antibacterial agent is used, the transparency of the corresponding transparent polymer material will decrease. The present invention uses alumina or replaces boron oxide. If the content exceeds 1 mol%, the melting temperature will be greatly increased, and if it exceeds 3 mol%, sintering will be impossible.

[0019] The present invention does not add rare earth metal oxides. Although CeO2 has a high redox potential and can inhibit the discoloration of the silver ion glass antibacterial agent during the firing process, the ionic radius of rare earth metal ions is larger, making it easier for them to occupy interstitial positions in the phosphoborate system glass network and bond with non-bridging oxygen. Silver ions are not easily burned into the glass structure during the firing process. Under high temperature conditions, reduction reactions are easily induced, resulting in a decrease in the silver ion content in the glass structure, resulting in the risk of easy discoloration and reduced antibacterial performance.

[0020] Based on the structure of phosphoborate glass, the present invention does not prefer alkali metal oxides, copper oxide, zinc oxide, calcium oxide, aluminum oxide, and rare earth metal oxides. However, it is not denied that these components may play a role in adjusting and improving glass properties in glass with specific molar ratios of phosphorus oxide, boron oxide, and magnesium oxide, and this is also within the scope of protection of the present invention. The introduction of 0.0001-5wt% of CeO2, CaO, CuO, ZnO, Al2O3, Na2O, V2O5, and other components described in the present invention can be used as components to adjust and improve transparency and stability outside the optimal ratio range of the glass antimicrobial agent composition of the present invention. Under conditions exceeding the content limits of the various components of the present invention, they can also play a role in improving transparency and stability. However, this treatment method is not preferred. Beneficial effects

[0021] This paper systematically experiments and studies the molar ratio of phosphorus oxide to boron oxide in phosphate borate glass, laying the foundation for the further development and application research of this type of glass. This paper also conducts detailed experiments and analysis on the effects of calcium oxide, zinc oxide, and magnesium oxide in phosphate borate glass systems, and selects magnesium oxide as a glass network modifier with superior optical tuning properties and higher stability. This provides data reference for the application of these three metal oxides in other glass systems, such as silicate glass and phosphate glass. This paper successfully prepares a silver-loaded glass antimicrobial agent, addressing the problem of silver ion discoloration caused by processing temperatures exceeding 260°C and the presence of benzene rings and carbon-carbon double bonds in polymer materials. The silver-loaded glass antimicrobial agent exhibits excellent transparency. Antimicrobial polyester and polycarbonate resins and products made from this agent exhibit a haze increase of less than 5% and a transmittance decrease of less than 2% for 3 mm thick samples. Particularly preferred are haze increases of less than 1% and transmittance decreases of less than 1%. The antibacterial performance of the antibacterial material prepared by the present invention meets the requirements of GB21551.2-2010. BRIEF DESCRIPTION OF THE DRAWINGS

[0022] FIG1 is a scanning electron microscope image of the glass antibacterial agent of Example 3 of the present invention;

[0023] FIG2 is a laser particle size distribution diagram of the glass antibacterial agent of Example 3 of the present invention;

[0024] FIG3 is a transparent comparison diagram of the antibacterial PCTG tablet of Example 3 of the present invention. Best Mode for Carrying Out the Invention

[0025] The preparation method of the silver-loaded glass antibacterial agent of the present invention comprises the following steps:

[0026] (1) The components or the corresponding acids, salts, oxides, and hydroxides are fully mixed (natural minerals can also be selected as raw materials, but natural minerals may contain excessive heavy metals or impurity ions, which is not preferred), and then melted at a high temperature of 1300-1450°C;

[0027] (2) The melt obtained in step (1) is then quenched to obtain glass in the form of flakes or blocks, which is then physically crushed to obtain a silver-loaded glass antibacterial agent.

[0028] The present invention also relates to a transparent antibacterial resin product and articles containing the silver-loaded glass antibacterial agent of the present invention, including but not limited to transparent antibacterial PCTG, PC, PET masterbatch with an effective content of 5-10wt% and articles thereof.

[0029] The transparent antimicrobial PCTG, PC, and PET resins described herein may also contain dispersants, nucleating agents, and the like, as needed to further reduce haze or increase light transmittance. However, since the haze and light transmittance of the transparent antimicrobial PCTG, PC, and PET resins described herein are already very close to those of the base resin material without the addition of an antimicrobial agent, the improvement is not significant.

[0030] The silver-loaded glass antibacterial agent of the present invention includes but is not limited to being applied to polymer resin materials such as PP, PE, ABS, PMMA, AS, Tritan, melamine, polyurethane, silicone, etc., and processed into corresponding products, such as plastic products.

[0031] When applied to water pipes, the silver-loaded glass antimicrobial agent of the present invention has a silver ion dissolution concentration of less than 5 ppb, reaching a maximum of 0.5 ppb, meeting the GB / T 17219-1998 safety assessment standard for drinking water distribution equipment and protective materials. Other silver-loaded glass antimicrobial agents have data exceeding 5 ppb, and most exceed 10 ppb. Modes for Carrying Out the Invention

[0032] The following provides a clear and complete description of the technical solutions in the embodiments of the present invention, in conjunction with the accompanying drawings. Obviously, the described embodiments are only some, and not all, of the embodiments of the present invention. All other embodiments derived by persons of ordinary skill in the art based on the embodiments of the present invention without inventive effort are intended to fall within the scope of protection of the present invention.

[0033] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one skilled in the art to which this invention pertains. The terms used in this specification of the present invention are for the purpose of describing specific embodiments only and are not intended to limit the present invention. The term "and / or" as used herein includes any and all combinations of one or more of the associated listed items.

[0034] Examples and Comparative Examples

[0035] The embodiments of the present invention will be described in detail below with reference to the examples, but those skilled in the art will appreciate that the following examples are intended only to illustrate the present invention and should not be construed as limiting the scope of the invention. Where specific conditions are not specified in the examples, conventional conditions were used. Where the manufacturers of the reagents or instruments are not specified, they are all conventional products that can be purchased commercially.

[0036] In the present invention, the migration concentration of silver is evaluated according to Appendix A of GB / T 17219-1998 Safety Evaluation Standard for Drinking Water Transmission and Distribution Equipment and Protective Materials, wherein the concentration of the silver-loaded glass antimicrobial agent in PPR is 0.5%.

[0037] In the present invention, the antibacterial test is carried out according to the standard test method of GB21551.2-2010; the powder morphology is analyzed by a scanning electron microscope, and the particle size distribution is measured by a laser particle size analyzer.

[0038] The following experiments were conducted to verify the effects of the present invention.

[0039] Examples 1 to 5: The components and compounds corresponding to the contents of the examples shown in Table 1 were mixed, and the resulting mixture was melted in an electric furnace at 1300 to 1450°C for 2 to 3 hours; the molten mixture was then removed from the furnace and poured into a graphite mold and allowed to cool to room temperature. The block of antibacterial glass was then ground with a jaw crusher or a ball mill, and finally subjected to physical ultrafine grinding to a particle size D90 of less than 10 microns, thereby obtaining the glass antibacterial agents of Examples 1 to 5 of the present invention, whose silver migration concentrations are shown in Table 1.

[0040] Comparative Examples 1 to 5: The components and compounds corresponding to the contents of the comparative examples shown in Table 1 were mixed, and the resulting mixture was melted in an electric furnace at 1300-1450°C for 2-3 hours; the molten mixture was then removed from the furnace and poured into a graphite mold and allowed to cool to room temperature. The block of antibacterial glass was then ground with a jaw crusher or a ball mill, and finally subjected to physical ultrafine grinding to a particle size D90 of less than 10 microns, thereby obtaining the glass antibacterial agents of Comparative Examples 1 to 5 of the present invention. The silver migration concentration is shown in Table 1.

[0041] Table 1 Implementation components and silver migration concentration

[0042]

[0043] Examples 6-15: The compositions of Examples 1-5 were mixed with PCTG resin in the proportions shown in Table 2. The mixtures were pelletized using a twin-screw extruder and injection molded into antibacterial PCTG sheets (5 cm x 5 cm, 3 mm thick; all haze and transmittance values ​​reported herein were obtained using 3 mm thick sheets). The samples described in Examples 6-15 were obtained. The antibacterial properties and transparency results are shown in Table 2.

[0044] Comparative Examples 6-15: The compositions of Comparative Examples 1-5 of the present invention were mixed with PCTG resin in the proportions shown in Table 3. The mixtures were pelletized using a twin-screw extruder and then injection molded into antibacterial PCTG sheets (5 cm x 5 cm, 3 mm thick; all haze and transmittance values ​​reported herein were measured using 3 mm thick sheets). The samples described in Comparative Examples 6-15 were obtained. The antibacterial properties and transparency results are shown in Table 3.

[0045] Table 2 Antibacterial properties and transparency of antibacterial polyester and polycarbonate samples

[0046] Table 3 Antibacterial properties and transparency of antibacterial polyester and polycarbonate samples of comparative examples

[0047] Comparative Example 16: Compared with Example 3, zinc oxide was used instead of magnesium oxide, while other factors remained unchanged. It was found that the glass exhibited crystallization.

[0048] Comparative Example 17: Compared with Example 3, zinc oxide was used to replace half of the magnesium oxide, while other factors remained unchanged. No crystallization occurred. However, in the experiment of using the zinc oxide in PCTG resin, it was found that the PCTG easily discolored.

[0049] Comparative Example 18: Compared with Example 3, calcium oxide was used instead of magnesium oxide, while other conditions remained unchanged. The results showed that crystallization also occurred.

[0050] Comparative Example 19: Compared with Example 3, with other conditions unchanged, 3 mol% of aluminum oxide was used instead of boron oxide. The results showed that the melting temperature needed to be increased by 150°C to achieve vitrification, and crystallization occurred during the cooling process of the glass melt.

[0051] Comparative Example 20: Compared with Example 3, with other conditions unchanged, 5 mol% of aluminum oxide was used instead of boron oxide. The results showed that it was difficult to achieve vitrification during the glass melting process.

[0052] Comparative Example 21: Compared with Example 3, 3 wt% sodium oxide was added while keeping other factors unchanged. The results showed that although the melting temperature was lowered, the glass antibacterial agent was easily discolored in the experiment of applying it to PCTG resin.

[0053] Comparative Example 22: Compared with Example 3, 3 wt% CeO2 was added while keeping other conditions unchanged. The results showed that it was difficult to achieve vitrification during the melting process.

[0054] Comparative Example 23: Compared with Example 3, other factors remained unchanged, but 3 mol% V2O5 was used to replace phosphorus oxide. As a result, it was found that the molten glass turned yellow.

[0055] Comparative Example 24: Compared with Example 3, 1 wt% CuO was added while keeping other conditions unchanged. The glass turned blue and unmelted dark lumps were formed at the bottom of the crucible.

[0056] Comparative Example 25: A glass antibacterial agent containing 2.0wt% Ag2O, 50mol% P2O5, 7mol% Na2O, 40mol% MgO, and 3mol% Y2O3 was prepared with reference to patent CN200410007612.X. The silver migration concentration was 39.7ppb. When added to PCTG at 0.5%, the haze value was 26.3.

[0057] Comparative Example 26: Referring to patent CN1202034C, a glass antibacterial agent containing 2.0wt% Ag2O, 30wt% P2O5, 15wt% B2O3, 30wt% ZnO, and 15wt% CaO was prepared. The silver migration concentration was 30.1ppb. When it was added to PCTG at 0.5%, the haze value was 56.3.

[0058] Comparative Example 27: Referring to Example 1 of Patent 202010430700.X, a glass antibacterial agent was prepared, the silver migration concentration of which was 22.7 ppb. It was added to PCTG at 0.5%, and its haze value was 36.3. Industrial Applicability

[0059] The experimental results of the examples and comparative examples show that glass with P2O5 and B2O3 as the main network formers within the molar content range specified by the present invention and magnesium oxide, silicon oxide, and cobalt oxide as network modifiers within the content specified by the present invention have the advantages of more stable structure, higher light transmittance, and better transparency. It has better color stability during the application and processing process, and the addition amount required to achieve antibacterial performance is lower. The migration concentration of silver is lower than 5ppb, meeting GB / T17219-1998.

[0060] The above description is only a preferred specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any technician familiar with the technical field, within the technical scope disclosed by the present invention, who makes equivalent replacements or changes based on the technical solution and inventive concept of the present invention, should be covered by the scope of protection of the present invention.

Claims

1. A silver-loaded glass antibacterial agent, characterized in that: Based on the total molar number of each component, calculated as oxide, the silver-loaded glass antibacterial agent contains: 11-15 mol% P2O5, 25-35 mol% B2O3, 50-60 mol% MgO; wherein the weight percentage is 0.1-3 wt% Ag2O, 0.003-0.05 wt% Co2O3, and 0.01-0.5 wt% SiO2.

2. A silver-loaded glass antibacterial agent as claimed in claim 1, characterized in that: The molar ratio of P2O5 and B2O3 is 1:1.5 to 1:

3.

3. The silver-loaded glass antibacterial agent according to claim 1, characterized in that: The silver-loaded glass antibacterial agent meets GB / T17219-1998, and the silver ion concentration is lower than 5ppb.

4. A transparent antibacterial resin product and article, characterized in that: Contains the silver-loaded glass antibacterial agent according to claim 1.

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