Ceramic glaze having antimicrobial property
Abstract
This record has no abstract on file.
Term
Projected expiry 16 February 2028.
- Priority
- Filed
- Granted
- Today
- Projected expiry
21 claims: 10 independent, 11 dependent
- 1REIVINDICAÇÕES 1. Composição de esmalte cerâmico antimicrobiano, caracterizada pelo fato de que compreende:uma base de esmalte cerâmico;e uma composição antimicrobiana incluindo: um primeiro agente antimicrobiano consistindo de Ag 2 CO3, e um segundo agente antimicrobiano que é um de BÍ2O3, CuO, SnO 2 , TiO 2 ou ZnO;em que o primeiro agente antimicrobiano está presente na composição de esmalte com uma concentração de cerca de dois a cerca de quatro por cento em peso da composição de esmalte;e em que o segundo agente antimicrobiano está presente na composição de esmalte com uma concentração de cerca de dois por cento a cerca de quatro por cento em peso da composição de esmalte.
- 2Composição de esmalte cerâmico antimicrobiano de acordo com a reivindicação 1, caracterizada pelo fato de que o segundo agente antimicrobiano é Bi 2 O 3 .
- 3Composição de esmalte cerâmico antimicrobiano de acordo com a reivindicação 1, caracterizada pelo fato de que o segundo agente antimicrobiano é ZnO.
- 4Composição de esmalte cerâmico antimicrobiano de acordo com a reivindicação 1, caracterizada pelo fato de que o primeiro agente antimicrobiano e o segundo agente microbiano estão presentes na composição de esmalte com concentrações substancialmente iguais.
- 5Composição de esmalte cerâmico antimicrobiano de acordo com a reivindicação 1, caracterizada pelo fato de que a concentração do primeiro agente antimicrobiano na composição de esmalte é cerca de dois por cento;em que o segundo agente antimicrobiano é um de Bi 2 O 3 , CuO, SnO 2 , ou ZnO.
- 6Composição de esmalte cerâmico antimicrobiano de acordo com a reivindicação 1, caracterizada pelo fato de que a concentração do primeiro agente antimicrobiano na composição de esmalte é cerca de quatro por cento;e em que o segundo agente antimicrobiano está presente na composição de esmalte com uma concentração de cerca de dois por cento.
- 7Composição de esmalte cerâmico antimicrobiano, caracterizada pelo fato de que compreende:uma base de esmalte cerâmico;e uma composição antimicrobiana incluindo: um primeiro agente antimicrobiano consistindo de Bi 2 O 3 , e um segundo agente antimicrobiano consistindo de ZnO;em que o primeiro agente antimicrobiano tem uma concentração na composição de esmalte cerâmico de cerca de dois por cento a cerca de quatro por cento;e em que o segundo agente antimicrobiano tem uma concentração de cerca de dois por cento a cerca de quatro por cento.
- 8Composição de esmalte cerâmico antimicrobiano, caracterizada pelo fato de que compreende:uma base esmalte cerâmico;e uma composição antimicrobiana sinergística incluindo um primeiro agente antimicrobiano e um segundo agente antimicrobiano, a composição antimicrobiana sendo um de: 2% Ag 2 CO 3 + 2% Bi 2 O 3 , 2% Ag 2 CO 3 + 2% CuO, 2% Ag 2 CO 3 + 4% SnO 2 , 2% Ag 2 CO 3 + 2% ZnO, 2% Ag 2 CO 3 + 4% ZnO, 2% Bi 2 O 3 + 2% CuO, 2% Bi 2 O 3 + 4% CuO, 2% CuO + 4% Ag 2 CO 3 , 2% CuO + 4% SnO 2 , 2% CuO + 2% TiO 2 , 2% CuO + 4% TiO 2 , 2% CuO + 4% ZnO, 2% SnO 2 + 4% Ag 2 CO 3 , 2% SnO 2 + 4% CuO, 2% TiO 2 + 4% Ag 2 CO 3 , 2% TiO 2 + 4% CuO, 2% ZnO + 4% Ag 2 CO 3 , ou 2% ZnO + 4% CuO.
- 9Composição de esmalte cerâmico antimicrobiano de acordo com a reivindicação 8, caracterizada pelo fato de que a combinação antimicrobiana sinergística é 2% Ag 2 CO 3 + 2% ZnO.
- 10Composição de esmalte cerâmico antimicrobiano, caracterizada pelo fato de que compreende:uma base de esmalte cerâmico;e uma composição antimicrobiana incluindo: um primeiro agente antimicrobiano consistindo de Bi 2 O 3 , e um segundo agente antimicrobiano consistindo de ZnO;em que o primeiro agente antimicrobiano está presente na composição de esmalte com uma concentração de cerca de um por cento a cerca de quatro por cento em peso da composição de esmalte;e em que o segundo agente antimicrobiano está presente na composição de esmalte com uma concentração de cerca de um por cento a cerca de quatro por cento em peso da composição de esmalte.
- 11Composição de esmalte cerâmico antimicrobiano de acordo com a reivindicação 10, caracterizada pelo fato de que:o primeiro agente antimicrobiano tem uma concentração na composição de esmalte cerâmico de cerca de dois por cento;e o segundo agente antimicrobiano tem uma concentração na composição de esmalte de cerca de dois por cento a cerca de quatro por cento.
- 12Composição de esmalte cerâmico antimicrobiano de acordo com a reivindicação 10, caracterizada pelo fato de que compreende ainda um terceiro agente antimicrobiano consistindo de Ag 2 CO 3 ;em que o primeiro agente antimicrobiano tem uma concentração na composição de esmalte cerâmico de cerca de um por cento a cerca de dois por cento;em que o segundo agente antimicrobiano tem uma concentração na composição de esmalte de cerca de um por cento a cerca de dois por cento;e em que o terceiro agente antimicrobiano tem uma concentração na composição de esmalte cerâmico de cerca de um por cento a cerca de dois por cento.
- 13Composição de esmalte cerâmico antimicrobiano de acordo com a reivindicação 12, caracterizada pelo fato de que:o primeiro agente antimicrobiano, segundo agente antimicrobiano e terceiro agente microbiano cada tem uma concentração na composição de esmalte cerâmico de cerca de um por cento.
- 14Composição de esmalte cerâmico antimicrobiano de acordo com a reivindicação 12, caracterizada pelo fato de que:o primeiro agente antimicrobiano, segundo agente antimicrobiano e terceiro agente antimicrobiano cada tem uma concentração na composição de esmalte cerâmico de cerca de dois por cento.
- 15Composição de esmalte cerâmico antimicrobiano de acordo com a reivindicação 12, caracterizada pelo fato de que:pelo menos um do primeiro agente antimicrobiano e do segundo agente antimicrobiano tem uma concentração na composição de esmalte cerâmico de cerca de dois por cento;e o terceiro agente antimicrobiano tem uma concentração na composição de esmalte cerâmico de cerca de um por cento.
- 16Substrato cerâmico esmaltado, caracterizado pelo fato de que compreende:um substrato cerâmico tendo uma primeira superfície de substrato;e uma composição de esmalte cerâmico queimada disposta sobre a superfície do primeiro substrato;em que a composição de esmalte cerâmico é a composição de esmalte cerâmico de uma das reivindicações 1 ou 7.
- 17Substrato cerâmico esmaltado, caracterizado pelo fato de que compreende:um substrato cerâmico tendo uma primeira superfície de substrato;e uma composição antimicrobiana sinergística queimada disposta sobre a superfície do primeiro substrato;em que a composição antimicrobiana sinergística é a composição de esmalte cerâmico como definida na reivindicação 8.
- 18Substrato cerâmico esmaltado, caracterizado pelo fato de que compreende:um substrato cerâmico tendo uma primeira superfície de substrato;e uma composição antimicrobiana sinergística queimada disposta sobre a superfície do primeiro substrato;em que a composição antimicrobiana sinergística é a composição de esmalte cerâmico de uma das reivindicações 10 ou 12.
- 19Método para fabricação de um substrato cerâmico esmaltado, caracterizado pelo fato de que compreende:aplicar uma composição de esmalte cerâmico antimicrobiano em um substrato cerâmico;e 5 queimar a composição de esmalte para transformar a composição de esmalte em um estado queimado;em que a composição de esmalte cerâmico antimicrobiano inclui uma composição antimicrobiana como definida em uma das reivindicações 1, 7, 10 ou 12. 10 20. Método para fabricação de uma composição de esmalte cerâmico antimicrobiano, caracterizado pelo fato de que compreende: prover uma base de esmalte cerâmico;adicionar a base de esmalte cerâmico uma composição antimicrobiana que é uma de: 15 composição antimicrobiana como definida na reivindicação 1, composição antimicrobiana como definida na reivindicação 7, composição antimicrobiana sinergística como definida na reivindicação 8, composição antimicrobiana como definida na reivindicação
- 2020 10,ou composição antimicrobiana como definida na reivindicação 12;moer a base de esmalte cerâmico e a composição antimicrobiana adicionada;
- 2125 reidratar a base de esmalte cerâmico moída;e opcionalmente, remisturar a base de esmalte reidratada.
Independent claims21
255 paragraphs in 21 sections, as filed
(54) Title: CERAMIC ENAMEL COMPOSITION (57) Summary:
ANTIMICROBIAL, CERAMIC SUBSTRATE
ENAMELED AND METHODS FOR MANUFACTURING
AN ENAMELED CERAMIC SUBSTRATE
CERAMIC ENAMEL COMPOSITION
ANTIMICROBIAL.
(30) Unionist Priority: 2/20/2007 us 60/890666,
02/20/2007 US 60/890673 (73) Holder (s): Microban Products Company (72) Inventor (s): Alvin Lamar Campbell Jr.
(74) Attorney (s): Momsen, Leonardos & Cia.
(86) International order: pct US2OO8O5419O from
16/02/2008 (87) International Publication: wo 2oos / io362ide
08/28/2008 “COMPOSITION OF ANTIMICROBIAL CERAMIC ENAMEL, ENAMELED CERAMIC SUBSTRATE, AND METHODS FOR THE MANUFACTURE OF AN ENAMELED CERAMIC SUBSTRATE AND AN ANTIMICROBIAL CERAMIC ENAMEL COMPOSITION” FIELD OF THE INVENTION
The present invention relates to the field of antimicrobial protection in a ceramic article or component thereof. More specifically, the present invention relates to a composition for imparting built-in and long-lasting antimicrobial characteristics to ceramic products.
BACKGROUND OF THE INVENTION
An area of commercial interest in particular in the art are ceramic articles and ceramic tiles. Ceramic tiles are commonly used in products that store, treat or transport water and liquid waste. Ceramic toilets, urinals, bidets, bathroom sinks (collectively known as sanitary ware), floors and other bathroom accessories are probably the most common example of such products.
When used to collect, contain or transport water, ceramic products often become stained by foam and films of biological origin (eg bacteria, fungi, mold, mildew). So far, the main method of removing foam and biological films from these ceramic products has been abrasion of the ceramic surface in the presence of a topical cleaning agent.
There is a need for a ceramic coating that has built-in protection against microbial growth and proliferation. However, existing technologies are somewhat limited in this regard. For example, the high temperatures used in ceramic firing processes typically exclude the use of organic antimicrobial agents.
Antibacterial compounds based on conventional inorganic silver (eg, zeolite, amorphous glass, sol-gel) are generally very expensive for commercial use. In addition, the incorporation of silver-based antimicrobial agents into ceramic enamels routinely presents problems with turbidity, cracking, discoloration and other undesirable consequences for the aesthetics of the enamel. There is a need for a ceramic coating that has built-in protection against microbial growth and proliferation.
Zinc oxide is known to have antimicrobial characteristics and has been used in the preparation of ceramic enamel compositions. However, known ceramic enamel compositions that rely exclusively on zinc oxide as an antimicrobial agent have not shown sufficient antimicrobial efficacy to control microbial growth and proliferation on ceramic surfaces.
Consequently, there is a need for a low-cost ceramic coating that offers persistent built-in antimicrobial protection.
DETAILED DESCRIPTION
As used here, the terms "microbe" or "microbial" should be interpreted as referring to any microscopic organisms studied by microbiologists or found in the environment of use of a ceramic article or enameled ceramic article. Such organisms include, but are not limited to, bacteria and fungi, as well as other single cell organisms, such as mold, mildew and algae. Viral particles and other infectious agents are also included in the term microbe.
In the same way, “antimicrobial” and similar terms should be interpreted as covering both, extermination of microbes, as well as microbistatic activities. That is, it is considered effective here if an antimicrobial composition reduces the number of microbes on a substrate or if the composition slows down the normal rate of microbial growth.
To facilitate discussion, this description uses the terms microbes and antimicrobial to denote broad-spectrum activity (for example, against bacteria and fungi). When speaking of efficacy against a particular microorganism or taxonomic classification, the more focused term will be used (for example, antifungal to denote efficacy against particular fungal growth).
Using the example above, it should be understood that efficacy against fungi does not in any way prevent the same antimicrobial composition from demonstrating effectiveness against another class.
For example, the discussion about the strong bacterial efficacy demonstrated by a described embodiment should not be interpreted to exclude the embodiment that also demonstrates antifungal activity. This method of presentation should not be construed as limiting the scope of the invention in any way.
A first embodiment is an antimicrobial ceramic enamel composition. A second embodiment described here is a method for making an antimicrobial ceramic enamel composition. The enamel composition comprises a plurality of conventional enamel ingredients and a combination of antimicrobial agents, as described more fully below.
The following brief discussion on ceramic tiles and in particular on ceramic enamel on the outer surfaces of ceramic products and glassy porcelain or ceramic production is provided as an aid to the reader. This discussion is presented in the context of the production of bathroom accessories. Those skilled in the art recognize that the production process for ceramic products may vary from those shown below, and that the ceramic enameling process described here is adaptable to other substrates.
Enamels are generally manufactured from powdered glass combined with colored oxides of elements such as cobalt, chromium, manganese, or nickel. The powder mixture is suspended in water and applied to the ceramic surface by spraying, painting, dipping or other known application methods.
The suspension, or slurry, in which the enamel is applied to the ceramic surface must have particular properties that ensure that the enamel is easy to apply, does not run during firing, and adheres well when wet and after firing. These properties of the slurry are often obtained by adding a small amount of clay to the suspension and, controlling both, the amount of water in the slurry as well as the size of the powder particles. Organic surfactants (eg surfactants, detergents) can also be added to the slurry to improve its properties.
The colors in enamels are controlled by adding coloring agents to the glazed components of the enamel. Special effects in enamels can also be produced. If salt is added to the oven during firing, the enamel develops a fine orange peel-like texture that can be uniform or irregular depending on conditions. An enamel that foams during firing has a coarse surface of broken bubbles known as bubble enamel.
It was treated to develop a baseline enamel composition, which is a conventional, non-antimicrobial ceramic enamel base, and methodology to assist in the identification of appropriate and effective antimicrobial agents. Through the specific background of the technique, the development of baseline enamel, its processing, and its maturation temperature are now briefly reviewed.
Two potential enamel fries were identified that did not contain any of the antimicrobial agents that could comprise at least 95% of the enamel composition. These frits were used to form enamel pastes that were applied to the unglazed burnt tile. These slurries were evaluated with r
different viscosities and solids content. It is also preferable that the enamels are easy to apply through different methods.
A conventional enamel composition used for experimental tests here is made up of 95% slow-burning enamel base (containing primarily S1O2 and secondarily, inter alia, KNaO, CaO, BaO, SrO AI2O3 and B<sub>2</sub>O<sub>3</sub>).
Alkaline earth oxide materials such as calcium carbonate, wolastonite, and zinc oxide are generally added as a raw material. Other alkaline earth oxides such as lead oxide, strontium oxide, barium oxide, and magnesium oxide are more typically added in the fried form. Alkaline earth oxides are advantageous because they provide a melting action without having a greater effect on thermal expansion r
of the enamel. Oxides can also serve as coloring compounds.
It is also present in the enamel composition of 5% EPK kaolin, and an extra 1% addition of Bentonite (an absorbent aluminum silicate clay formed from volcanic ash and well known to those skilled in the art). This dry material is mixed in a sufficient amount of deionized water to produce an enamel slurry with a specific density of 1.35 ± 0.05 g / cm<sup>3</sup>. This represents a solids content of 41.74%.
Notable among the many antimicrobial agents used were Ag<sub>2</sub>CO<sub>3</sub> (CAS No. 534-16-7); Bi<sub>2</sub>O<sub>3</sub> (CAS No. 1304-76-3); CuO (CAS No. 1317-38-0); SnO<sub>2</sub> (CAS No. 18282-10-5); Uncle<sub>2</sub> (anatase; CAS No. 1346367-7) and ZnO (CAS No. 1314-13-2).
An antimicrobial enamel composition was made by adding together (for example, by mixing) components of the conventional enamel composition and combinations of antimicrobial agents. The components and antimicrobial agent (s) were added based on the weight of solids content of the baseline enamel, excluding such antimicrobial agent (s). The enamel base is described in greater detail above.
The enamel base, with antimicrobial agent (s) mixed in it, was then ground in a ball mill for fifteen minutes. The ground enamel base was kept overnight to allow for hydration, and was then remixed. The antimicrobial enamel composition was then ready to be applied to a substrate (for example, a non-glazed tile).
All material addition calculations are based on the percentage of baseline enamel solids and the specific density is checked before each group of material assessment samples is processed. Each material to be evaluated is added to 1000 milliliters of baseline enamel.
r
It is expected, however, that other conventional ceramic enamel compositions can be replaced without deviating from the essential characteristics of the antimicrobial ceramic enamel as described here.
In a third embodiment, a method for fixing a ceramic enamel on a substrate provides the substrate with durable antimicrobial properties. The method generally comprises providing a ceramic enamel composition having one or more antimicrobial agents arranged therein as specified in the present description, applying the antimicrobial enamel composition to a substrate, and curing the enamel composition according to conventional enamel firing techniques. .
The work in progress used immersion to apply the enamel formulation on tiles, although other application methods known to those skilled in the art can be used. The enamel is then dried and fixed to the ceramic surface by burning.
During firing, the powdered glass softens and balances greatly on the ceramic surface, reacting with the ceramic substrate to form a strong and adherent bond between them. If an enamel is applied to an already burnt ceramic substrate, a second burn is required to melt and bond the enamel to the substrate. Alternatively, it is possible to apply the glaze to an unburned ceramic and to burn both the glaze and the substrate together.
Various components, such as alkali oxide, borates, and lead oxide can be added to the ceramic enamel composition to facilitate softening at lower temperatures so that the enamel flows more easily during firing and to minimize roughness and defects on the ceramic enamel surface. The present antimicrobial combinations are compatible with these common additives.
The initial stage of a typical ceramic production process is the production of slip or slurry, a clay from which bathroom ceramic products are made. The slip is made from a mixture of clays, kaolin, phyllites, feldspar and quartz.
Individual pieces are molded by pouring the slip into molds made of plaster or microporous resin. In molding processes using plaster molds, the pieces are formed by absorbing the water contained in the slip through the capillary action of the plaster. As the water leaves the slip, the piece solidifies to a point where the mold can be opened. The still malleable part is then removed from the mold.
Molding processes that use resin molds are called “high pressure” processes. Parts are formed by filtering the water contained in the slip clay through micropores in the resin molds by applying pressure. The water is eliminated through the injection of compressed gas along the molds.
After molding and removing the molds, the pieces go to dry drying under controlled temperature and humidity (approximately 90 degrees C). The drying cycle takes about 7 hours, reducing the part's water content from about 16% to less than 1%. Following this, the parts are inspected for possible failures. The pieces then go to the coating process. The coating process is alternatively referred to as the enameling step.
The enameling stage typically comprises the application of ceramic enamel on the parts using pistols in individual booths equipped with an exhaust system and a water curtain. A typical ceramic enamel is produced from a mixture of kaolin, feldspar, quartz, colorants and other additives. Once coated, the pieces are burned in continuous sieves, reaching temperatures of around 1250 ° C in a cycle of approximately 15 hours. The firing process gives the enameled piece an appearance with color and transparency that is typical of vitreous porcelain.
The procedure for making samples for material evaluation is simple. A baseline enamel reservoir, as described above, is maintained. Tiles samples having been applied on or on them the present enamel composition; the present description refers to immersed sample tiles.
Each immersed tile was placed inside a refractory clay box, each refractory clay box capable of holding up to twenty tiles. The refractory clay box was placed inside one of the two electric shafts and burned to a 06 pyrometric cone equivalent. This measure of thermal history is approximately equivalent to 1889 ° F or 1062 ° C. Baseline enamel samples were fired at temperatures in the range 1888 ° F to 2194 ° F.
The above procedure is similar to applying enamel in a production environment. Final baseline enamel formulations resulted in samples having a glassy surface with a low temperature, high resistance to dye absorption, and showing no antimicrobial properties.
Microscopic images of the baseline tile / enamel interface revealed complete enamel vitrification without the inclusion of bubbles or unfused materials. Baseline samples are the foundation for comparing and judging candidate materials. The baseline enamel adopted is simple in composition, easy to process and apply, and has a low firing temperature. These attributes greatly facilitate the evaluation of candidate samples for material.
In production, this layer of dry enamel is about 2 millimeters thick. A more cost-effective method for producing an antimicrobial surface would involve the use of a much thinner secondary enamel applied over the regular enamel (first). This enamel thickness could be 0.5 mm or less in thickness.
r
Exposure of the enameled tile to microbes is expected to result in microbial contact only with the enameled composition on the surface of the enameled tile. The material below the surface is trapped inside the enamel glass and is thus sequestered from microbes.
A variety of antimicrobial agents were tested in the baseline enamel composition after enamelling a substrate sample. Of these compounds, a variety of combinations were also evaluated, as detailed in the following discussion and examples.
In a fourth embodiment, a ceramic article having the antimicrobial enamel composition described above exhibits durable antimicrobial properties. The antimicrobial ceramic article comprises a substrate, for example, a ceramic substrate, having at least one first surface; and a burnt or cured enamel arranged on at least a portion of the first surface. The ceramic enamel composition used in this embodiment is the same as that described in the first embodiment.
Antimicrobial agents were used to manufacture a range of antimicrobial enamel compositions, each composition consisting of one, two, or three antimicrobial agents. Several ceramic articles were then prepared to test the antimicrobial characteristics of the enamels mentioned. The test articles comprised an underlying ceramic substrate made from a standard commercial slip.
The enamel used in the test was the baseline enamel previously described, to which varying amounts of combinations of antimicrobial agents were added as mentioned. The enamel composition was applied to the articles by immersion, and the test articles were then burned.
As mentioned, combinations of two antimicrobial agents have been evaluated for antimicrobial efficacy in glazes fired on ceramic substrates. Ag compounds<sub>2</sub>CO<sub>3</sub>, Bi<sub>2</sub>O<sub>3</sub> CuO, SnO<sub>2 </sub>Uncle<sub>2</sub> and ZnO were evaluated. Each compound was tested sequentially at 2% in parallel with one of the other five compounds. The second compound was tested at either 2% or 4%. As an example, using Ag<sub>2</sub>CO<sub>3</sub> and ZnO, then the following possibilities were tested: 2% Ag<sub>2</sub>CO<sub>3</sub> and 2% ZnO; 2% Ag<sub>2</sub>CO<sub>3</sub> and 4% ZnO, and 4% Ag<sub>2</sub>CO<sub>3</sub> and 2% ZnO.
Continuing with this exemplary combination of antimicrobial agents, the combination of 4% Ag<sub>2</sub>CO<sub>3</sub> and 4% ZnO has not been tested, as combinations of 4% / 4% are generally considered too expensive to sell and / or have been observed to negatively affect the aesthetics of the final enamel. It is expected that such combinations could show effectiveness if the combination of 2% / 4% and / or 4% / 2% were effective, although antagonistic effects have been observed in some combinations. Each compound was sequentially tested at 2% in tandem with the other five compounds.
Test articles were also prepared without any antimicrobial agents in the enamel for use as a negative control.
The measure of antimicrobial efficacy is the reduction in the number of organisms surviving the test protocol compared to the baseline standard. Minimum efficiency is assumed to result in a reduction level of 1 common logarithm, (log (Sample Std / NOS NOS)).
Three samples from each addition level and three baseline enamel samples were then tested in triplicates. The test is in accordance with the modified JIS test protocol Z2801: 2000 (available from the Japanese Industrial Standards Committee, Tokyo, Japan). The Z2801 protocol is an internationally known standard test for antimicrobial activity and efficacy. The protocol and specific changes made to it are summarized below.
Pieces of tile samples having a diameter of approximately 55 mm were used. The ceramic enamel composition was applied and burned according to the instructions for the commercial enamel base employed. This process produced test discs having an area of approximately 2500 square millimeters on the top surface.
The comparison test for antimicrobial efficacy used Klebsiella pneumoniae, ATCC 4352. The test organism was grown, and an exponentially growing portion of the culture was collected in a Japanese nutrient medium (JNB) diluted to 1/500. An inoculum was prepared in about 10<sup>6</sup> colony forming units (CFU) per millimeter by dilution with 1/500 JNB.
A tile sample was placed on a tissue moistened in the laboratory on a culture plate, and 75 microliters of test inoculum (~ 0.8 χ 10<sup>5</sup> CFU) were pipetted onto the sample surface. A slurry for covering or film was placed on and in contact with the inoculum to ensure uniform and substantially complete coverage of the inoculum on the sample surface. The culture plate was then incubated for 24 hours at 37 ° C with moisture.
The bacteria in the sample and slurry for covering / film were recovered, collected in a neutralizing medium, and counted. The antimicrobial activity of the test samples is expressed here as a log reduction value, compared to the bacterial growth of the corresponding untreated (control) sample. A log reduction is expressed as log (U / B), where U is the average CFU of the test organism from the inoculum recovered in the neutralizing medium from the (untreated) tile sample of the negative control, and B is the average CFU of the test organism recovered in the neutralizing medium from the inoculated sample.
EXAMPLE 1
In a first example, 2% Ag<sub>2</sub>CO<sub>3</sub> was used as a first antimicrobial agent in a family of enamel compositions, which also contained a second antimicrobial agent: one from Bi<sub>2</sub>O<sub>3</sub> CuO, SnO<sub>2i</sub> Uncle<sub>2</sub> or ZnO. The second antimicrobial agent was tested at both 2% and 4%. Tile samples were enameled and the tiles were evaluated according to the modified JIS Z2801: 2000 test protocol described above for the effect of the enameled tile on bacterial reduction. The results are shown in TABLE 1.
EXAMPLE 2
In a second example, 2% Bi<sub>2</sub>O<sub>3</sub> was used as a first antimicrobial agent in a family of enamel compositions, which also contained a second antimicrobial agent: one from Ag<sub>2</sub>CO<sub>3 </sub>CuO, SnO<sub>2;</sub> Uncle<sub>2</sub> or ZnO. The second antimicrobial agent was tested at both 2% and 4%. Tile samples were enameled and the tiles were evaluated according to the modified JIS Z2801: 2000 test protocol described above for the effect of the enameled tile on bacterial reduction. The results are shown in TABLE 2.
TABLE 1
Antimicrobial Combination: Ag<sub>2</sub>CO<sub>3</sub> K. pneumoniae
<td>Ag<sub>2</sub>CO<sub>3</sub></td><td>Bi<sub>2</sub>O<sub>3</sub></td><td>CuO</td><td>SnO<sub>2</sub></td><td>Uncle<sub>2</sub></td><td>ZnO</td><td>Log reduction</td>
<td> -</td><td> -</td><td> -</td><td> -</td><td> -</td><td> -</td><td>AT</td>
<td> 2%</td><td> -</td><td> -</td><td> -</td><td> -</td><td> -</td><td> 2,4</td>
<td> 2%</td><td> 2%</td><td> -</td><td> -</td><td> -</td><td> -</td><td> 3,6</td>
<td> 2%</td><td> 4%</td><td> -</td><td> -</td><td> -</td><td> -</td><td> 3,0</td>
<td> 2%</td><td> -</td><td> 2%</td><td> -</td><td> -</td><td> -</td><td> 3,9</td>
<td> 2%</td><td> -</td><td> 4%</td><td> -</td><td> -</td><td> -</td><td> 3,8</td>
<td> 2%</td><td> -</td><td> -</td><td> 2%</td><td> -</td><td> -</td><td> 3,2</td>
<td> 2%</td><td> -</td><td> -</td><td> 4%</td><td> -</td><td> -</td><td> 1,9</td>
<td> 2%</td><td> -</td><td> -</td><td> -</td><td> 2%</td><td> -</td><td> 2,4</td>
<td> 2%</td><td> -</td><td> -</td><td> -</td><td> 4%</td><td> -</td><td> 2,7</td>
<td> 2%</td><td> -</td><td> -</td><td> -</td><td> -</td><td> 2%</td><td> 3,0</td>
<td> 2%</td><td> -</td><td> -</td><td> -</td><td> -</td><td> 4%</td><td> 3,3</td>
EXAMPLE 3
In a third example, 2% CuO was used as a first antimicrobial agent in a family of enamel compositions, which also contained a second antimicrobial agent: one from Ag<sub>2</sub>CO3<sub>> </sub>B12O3, SnO<sub>2</sub>. Uncle<sub>2</sub> or ZnO. The second antimicrobial agent was tested at both 2% and 4%. Tile samples were enameled and the tiles were evaluated according to the modified JIS Z2801: 2000 test protocol described above for the effect of the enameled tile on bacterial reduction. The results are shown in TABLE 3.
TABLE 2
Antimicrobial Combination: Bi<sub>2</sub>O<sub>3</sub> K. pneumoniae
<td>Bi<sub>2</sub>O<sub>3</sub></td><td>Ag<sub>2</sub>CO<sub>3</sub></td><td>CuO</td><td>SnO<sub>2</sub></td><td>Uncle<sub>2</sub></td><td>ZnO</td><td>Log reduction NA</td>
<td> 2%</td><td> -</td><td> -</td><td> -</td><td> -</td><td> -</td><td> 0,8</td>
<td> 2%</td><td> 2%</td><td> -</td><td> -</td><td> -</td><td> -</td><td> 1,3</td>
<td> 2%</td><td> 4%</td><td> -</td><td> -</td><td> -</td><td> -</td><td> 3,7</td>
<td> 2%</td><td> -</td><td> 2%</td><td> -</td><td> -</td><td> -</td><td> 1,9</td>
<td> 2%</td><td> -</td><td> 4%</td><td> -</td><td> -</td><td> -</td><td> 3,1</td>
<td> 2%</td><td> -</td><td> -</td><td> 2%</td><td> -</td><td> -</td><td> 0,5</td>
<td> 2%</td><td> -</td><td> -</td><td> 4%</td><td></td><td> -</td><td> 0,9</td>
<td> 2%</td><td> -</td><td> -</td><td> -</td><td> 2%</td><td> -</td><td> -0,2</td>
<td> 2%</td><td> -</td><td> -</td><td> -</td><td> 4%</td><td> -</td><td> 0,8</td>
<td> 2%</td><td> -</td><td> -</td><td> -</td><td> -</td><td> 2%</td><td> 0,7</td>
<td> 2%</td><td> -</td><td> -</td><td> -</td><td> -</td><td> 4%</td><td> 1,4</td>
TABLE 3
Antimicrobial Combination: CuO K. pneumoniae
<td>CuO</td><td>Ag<sub>2</sub>CO<sub>3</sub></td><td>Bi<sub>2</sub>O<sub>3</sub></td><td>SnO<sub>2</sub></td><td>Uncle<sub>2</sub></td><td>ZnO</td><td>Log reduction AT</td>
<td> 2%</td><td> -</td><td> -</td><td> -</td><td> -</td><td> -</td><td> 0,4</td>
<td> 2%</td><td> 2%</td><td> -</td><td> -</td><td> -</td><td> -</td><td> 3,8</td>
<td> 2%</td><td> 4%</td><td> -</td><td> -</td><td> -</td><td> -</td><td> 4,0</td>
<td> 2%</td><td> -</td><td> 2%</td><td> -</td><td> -</td><td> -</td><td> 2,5</td>
<td> 2%</td><td> -</td><td> 4%</td><td> -</td><td> -</td><td> -</td><td> 1,9</td>
<td> 2%</td><td> -</td><td> -</td><td> 2%</td><td> -</td><td> -</td><td> 0,3</td>
<td> 2%</td><td> -</td><td> -</td><td> 4%</td><td> -</td><td> -</td><td> 2,4</td>
<td> 2%</td><td> -</td><td> -</td><td> -</td><td> 2%</td><td> -</td><td> 2,0</td>
<td> 2%</td><td> -</td><td> -</td><td> -</td><td> 4%</td><td> -</td><td> 2,3</td>
<td> 2%</td><td> -</td><td> -</td><td> -</td><td> -</td><td> 2%</td><td> 0,5</td>
<td> 2%</td><td> -</td><td> -</td><td> -</td><td> -</td><td> 4%</td><td> 3,0</td>
EXAMPLE 4
In a fourth example, 2% SnO<sub>2</sub> was used as a first antimicrobial agent in a family of enamel compositions, which also contained a second antimicrobial agent: one from Ag<sub>2</sub>CO3<sub>5</sub> BIO2O3, CuO, TiO<sub>2</sub> or ZnO. The second antimicrobial agent was tested at both 2% and 4%. Tile samples were enameled and the tiles were evaluated according to the modified JIS Z2801: 2000 test protocol described above for the effect of the enameled tile on bacterial reduction. The results are shown in TABLE 4.
TABLE 4
Antimicrobial Combination: SnO<sub>2</sub> K. pneumoniae
<td>SnO<sub>2</sub></td><td>Ag<sub>2</sub>CO<sub>3</sub></td><td>Bi<sub>2</sub>O<sub>3</sub></td><td>CuO</td><td>Uncle<sub>2</sub></td><td>ZnO</td><td>Log reduction</td>
<td> -</td><td> -</td><td> -</td><td> -</td><td> -</td><td> -</td><td>AT</td>
<td> 2%</td><td> -</td><td> -</td><td> -</td><td> -</td><td> -</td><td> 0,1</td>
<td> 2%</td><td> 2%</td><td> -</td><td> -</td><td> -</td><td> -</td><td> 0,5</td>
<td> 2%</td><td> 4%</td><td> -</td><td> -</td><td> -</td><td> -</td><td> 3,7</td>
<td> 2%</td><td> -</td><td> 2%</td><td> -</td><td> -</td><td> -</td><td> 1,2</td>
<td> 2%</td><td> -</td><td> 4%</td><td> -</td><td> -</td><td> -</td><td> 0,5</td>
<td> 2%</td><td> -</td><td> -</td><td> 2%</td><td> -</td><td> -</td><td> 0,5</td>
<td> 2%</td><td> -</td><td> -</td><td> 4%</td><td> -</td><td> -</td><td> 4,0</td>
<td> 2%</td><td> -</td><td> -</td><td> -</td><td> 2%</td><td> -</td><td> 0,0</td>
<td> 2%</td><td> -</td><td> -</td><td> -</td><td> 4%</td><td> -</td><td> 0,1</td>
<td> 2%</td><td> -</td><td> -</td><td> -</td><td> -</td><td> 2%</td><td> 0,2</td>
<td> 2%</td><td> -</td><td> -</td><td> -</td><td> -</td><td> 4%</td><td> 0,4</td>
TABLE 5
Antimicrobial Combination: T1O2 K. pneumoniae
<td>T1O2</td><td>Ag<sub>2</sub>CO<sub>3</sub></td><td>B12O3</td><td>CuO</td><td>SnO<sub>2</sub></td><td>ZnO</td><td>Log reduction AT</td>
<td> 2%</td><td> -</td><td> -</td><td> -</td><td> -</td><td> -</td><td> 0,0</td>
<td> 2%</td><td> 2%</td><td> -</td><td> -</td><td> -</td><td> -</td><td> 0,8</td>
<td> 2%</td><td> 4%</td><td> -</td><td> -</td><td> -</td><td> -</td><td> 3,6</td>
<td> 2%</td><td> -</td><td> 2%</td><td> -</td><td> -</td><td> -</td><td> 0,7</td>
<td> 2%</td><td> -</td><td> 4%</td><td> -</td><td> -</td><td> -</td><td> 0,7</td>
<td> 2%</td><td> -</td><td> -</td><td> 2%</td><td> -</td><td> -</td><td> 0,4</td>
<td> 2%</td><td> -</td><td> -</td><td> 4%</td><td> -</td><td> -</td><td> 3,9</td>
<td> 2%</td><td> -</td><td> -</td><td> -</td><td> 2%</td><td> -</td><td> 0,0</td>
<td> 2%</td><td> -</td><td> -</td><td> -</td><td> 4%</td><td> -</td><td> 0,5</td>
<td> 2%</td><td> -</td><td> -</td><td> -</td><td> -</td><td> 2%</td><td> 0,0</td>
<td> 2%</td><td> -</td><td> -</td><td> -</td><td> -</td><td> 4%</td><td> 0,2</td>
EXAMPLE 5
In a fifth example, 2% TiO<sub>2</sub> was used as a first antimicrobial agent in a family of enamel compositions, which also contained a second antimicrobial agent: one from Ag<sub>2</sub>CO<sub>3j</sub> Bi<sub>2</sub>O<sub>3</sub>, CuO, SnO<sub>2</sub> or ZnO. The second antimicrobial agent was tested at both 2% and 4%. Tile samples were enameled and the tiles were evaluated according to the modified JIS Z2801: 2000 test protocol described above for the effect of the enameled tile on bacterial reduction. The results are shown in the TABLE
5.
EXAMPLE 6
In a sixth example, 2% ZnO was used as a first antimicrobial agent in a family of enamel compositions, which also contained a second antimicrobial agent: one from Ag<sub>2</sub>CO<sub>3;</sub> Bi<sub>2</sub>O<sub>3</sub>, CuO, SnO<sub>2</sub> or TiO<sub>2</sub>The second antimicrobial agent was tested at both 2% and 4%. Tile samples were enameled and the tiles were evaluated according to the modified JIS Z2801: 2000 test protocol described above for the effect of the enameled tile on bacterial reduction. The results are shown in the TABLE
6.
TABLE 6
Antimicrobial Combination: ZnO K. pneumoniae
<td>ZnO</td><td>Ag<sub>2</sub>CO<sub>3</sub></td><td>Bi<sub>2</sub>O<sub>3</sub></td><td>CuO</td><td>SnO<sub>2</sub></td><td>Uncle<sub>2</sub></td><td>Log reduction</td>
<td> -</td><td> -</td><td> -</td><td> -</td><td> -</td><td> -</td><td>AT</td>
<td> 2%</td><td> -</td><td> -</td><td> -</td><td> -</td><td> -</td><td> 0,4</td>
<td> 2%</td><td> 2%</td><td> -</td><td> -</td><td> -</td><td> -</td><td> 2,4</td>
<td> 2%</td><td> 4%</td><td> -</td><td> -</td><td> -</td><td> -</td><td> 3,7</td>
<td> 2%</td><td> -</td><td> 2%</td><td> -</td><td> -</td><td> -</td><td> 1,3</td>
<td> 2%</td><td> -</td><td> 4%</td><td> -</td><td> -</td><td> -</td><td> 1,5</td>
<td> 2%</td><td> -</td><td> -</td><td> 2%</td><td> -</td><td> -</td><td> 0,5</td>
<td> 2%</td><td> -</td><td> -</td><td> 4%</td><td> -</td><td> -</td><td> 3,7</td>
<td> 2%</td><td> -</td><td> -</td><td> -</td><td> 2%</td><td> -</td><td> 0,2</td>
<td> 2%</td><td> -</td><td> -</td><td> -</td><td> 4%</td><td> -</td><td> 0,2</td>
<td> 2%</td><td> -</td><td> -</td><td> -</td><td> -</td><td> 2%</td><td> -0,1</td>
<td> 2%</td><td> -</td><td> -</td><td> -</td><td> -</td><td> 4%</td><td> 0,1</td>
<td colspan="2">RESULTS</td><td></td><td></td><td></td><td></td><td></td>
<td></td><td>When</td><td>two</td><td>agents</td><td colspan="2">antimicrobials</td><td>chemicals are</td>
<td>used in</td><td colspan="2">combination, in</td><td colspan="2">a composition</td><td>only</td><td>or like two</td>
separate additions at the point of use, three results are possible: 1) an additive (neutral) effect; 2) an antagonistic effect; or 3) a synergistic effect.
An additive (neutral) effect has no economic advantage over individual antimicrobial agents. An antagonistic effect could produce a negative result or reduced effectiveness.
Only synergism, which is much less likely than an additive or antagonistic effect, has a positive result and thus has economic advantages.
According to the invention, the combinations identified below demonstrate an unexpected synergistic antimicrobial effect on a burnt ceramic enamel. The combinations of the first and second antimicrobial agents, as described here, achieve superior antimicrobial activity with lower concentrations of antimicrobial agent as compared to the antimicrobial capacity of any antimicrobial agent alone. Such a superior effect has a distinct economic advantage and increases the effectiveness of the antimicrobial combination per unit weight.
Examining the results for antimicrobial agents individually and in combinations where the first antimicrobial agent is 2% Ag<sub>2</sub>CO3 (results in
TABLE 7), it can be seen that the addition of 2% of an antimicrobial agent alone demonstrated a range of effective results: Ag<sub>2</sub>CC> 3 (2.4 effectiveness), Bi<sub>2</sub>C> 3 (0.8; weak efficacy), CuO (0.4; very weak efficacy), ZnO (0.4; very weak efficacy), SnO<sub>2</sub> (0.1; essentially no effectiveness) and TiO<sub>2</sub> (0.0; no effectiveness).
However, it can be seen quickly that simple additions of a second 2% antimicrobial agent resulted in either an additive, antagonistic, or synergistic effect. In addition, the addition of the second 4% antimicrobial agent did not yield results according to expectations based on the results of testing individual antimicrobial agents or combinations of antimicrobial agents [2% + 2%].
For Ag combinations<sub>2</sub>CC> 3 and Bi<sub>2</sub>O<sub>3></sub> the combination [2% Ag<sub>2</sub>CO<sub>3</sub> + 2% Bi<sub>2</sub>O<sub>3</sub>] exhibits a synergistic effect with respect to the results that can be expected.
However, it can be seen that twice the level of the second antimicrobial agent (ie, [2% Ag<sub>2</sub>CC> 3 +
4% Bi<sub>2</sub>O<sub>3</sub>]) has an antagonistic effect, in which the observed efficacy is less than both (a) the expected value of log reduction of additive to [2% Ag<sub>2</sub>CC> 3 + 4% Bi<sub>2</sub>C> 3]; and (b) the observed value of log reduction for the combination [2% Ag<sub>2</sub>CC> 3 + 2% BIO2] 18
TABLE 7
<td></td><td colspan="4">Antimicrobial Combination: Ag<sub>2</sub>CO<sub>3</sub></td><td colspan="2">K. pneumoniae</td>
<td>Ag<sub>2</sub>CO<sub>3</sub></td><td>Bi<sub>2</sub>O<sub>3</sub></td><td>CuO</td><td>SnO<sub>2</sub></td><td>Uncle<sub>2</sub></td><td>ZnO</td><td>Log reduction</td>
<td> -</td><td> -</td><td> -</td><td> -</td><td> -</td><td> -</td><td>AT</td>
<td> 2%</td><td> -</td><td> -</td><td> -</td><td> -</td><td> -</td><td> 2,4</td>
<td> -</td><td> 2%</td><td> -</td><td> -</td><td> -</td><td> -</td><td> 0,8</td>
<td> 2%</td><td> 2%</td><td> -</td><td> -</td><td> -</td><td> -</td><td> 3,6</td>
<td> 2%</td><td> 4%</td><td> -</td><td> -</td><td> -</td><td> -</td><td> 3,0</td>
<td> 2%</td><td></td><td></td><td></td><td></td><td></td><td> 2,4</td>
<td> -</td><td> -</td><td> 2%</td><td> -</td><td> -</td><td> -</td><td> 0,4</td>
<td> 2%</td><td> -</td><td> 2%</td><td> -</td><td> -</td><td> -</td><td> 3,9</td>
<td> 2%</td><td> -</td><td> 4%</td><td> -</td><td> -</td><td> -</td><td> 3,8</td>
<td> 2%</td><td></td><td></td><td></td><td></td><td></td><td> 2,4</td>
<td> -</td><td> -</td><td> -</td><td> 2%</td><td> -</td><td> -</td><td> 0,1</td>
<td> 2%</td><td> -</td><td> -</td><td> 2%</td><td> -</td><td> -</td><td> 3,2</td>
<td> 2%</td><td> -</td><td> -</td><td> 4%</td><td></td><td></td><td> 1,9</td>
<td> 2%</td><td></td><td></td><td></td><td></td><td></td><td> 2,4</td>
<td> -</td><td> -</td><td> -</td><td> -</td><td> 2%</td><td> -</td><td> 0,0</td>
<td> 2%</td><td> -</td><td> -</td><td> -</td><td> 2%</td><td> -</td><td> 2,4</td>
<td> 2%</td><td> -</td><td> -</td><td> -</td><td> 4%</td><td> -</td><td> 2,7</td>
<td> 2%</td><td></td><td></td><td></td><td></td><td></td><td> 2,4</td>
<td> -</td><td> -</td><td> -</td><td> -</td><td> -</td><td> 2%</td><td> 0,4</td>
<td> 2%</td><td> -</td><td> -</td><td> -</td><td> -</td><td> 2%</td><td> 3,0</td>
<td> 2%</td><td> -</td><td> -</td><td> -</td><td> -</td><td> 4%</td><td> 3,3</td>
<td></td><td>For</td><td colspan="2">combinations of</td><td>Ag<sub>2</sub>CO<sub>3</sub></td><td>and CuO,</td><td>the combination [2%</td>
Ag<sub>2</sub>CO<sub>3</sub> + 2% CuO] exhibits a strong synergistic effect in relation to the expected results based on purely additive principles. Increase the level of the second antimicrobial agent twice (that is, [2% Ag<sub>2</sub>CO<sub>3</sub> + 4% CuO]) destroys the synergistic effect, instead of resulting in antagonism: the observed effectiveness of the combination [2% Ag<sub>2</sub>CO<sub>3</sub> + 4% CuO] (3.8) is essentially the same as the combination [2% Ag<sub>2</sub>CO<sub>3</sub> + 2% CuO] (3.9 / 3.8) and well below the very high log reduction expected for this combination.
Ag<sub>2</sub>CO<sub>3</sub> and SnO<sub>2</sub> demonstrated a strong and surprising synergy for the combination [2% Ag<sub>2</sub>CO<sub>3</sub> + 2% SnO<sub>2</sub>] (3.2 log reduction). Unexpectedly, the combination of Ag<sub>2</sub>CO<sub>3</sub> and SnO<sub>2</sub> showed marked antagonism when the SnO concentration<sub>2</sub> was doubled to 4%:
the log reduction fell to 1.9, well below both the observed results of
3.2 for the combination [2% Ag<sub>2</sub>CO3 + 2% SnO<sub>2</sub>] as well as the expected additive result.
Results for 2% Ag<sub>2</sub>CO3 and 2% TiO<sub>2</sub> were concluded to be merely additives. Unexpectedly, however, the duplication of TiO<sub>2</sub> to 4% resulted in a lesser synergistic effect: the effectiveness of the combination [2% Ag<sub>2</sub>CO<sub>3</sub> + 4% TiO<sub>2</sub>] (2.7 log reduction value) was slightly above both the expected additive effect values for the combination and the log reduction observed for the combination [2% Ag<sub>2</sub>CC> 3 + 4% TiO<sub>2</sub>].
The evaluation of Ag combinations<sub>2</sub>CO<sub>3</sub> + ZnO showed marginal synergy for the combination [2% Ag<sub>2</sub>CC> 3 + 4% ZnO] (3.0 observed log reduction value). The synergy was decreased with the increase in the concentration of ZnO to 4% (3.3 real).
The data presented for the other two combinations of antimicrobial compounds can also be analyzed, and other identified examples of additive, synergistic, and antagonistic effects.
Several combinations were judged to be of particular interest. These combinations are listed in Table 8, as showing synergistic effects. That is, the observed log reduction values of the combinations exceeded a statistically significant margin from the expected log reduction values based on the performance of the individual antimicrobial agent components of each combination.
In addition to the above binary combinations, a less expansive set of tertiary combinations was evaluated. These combinations comprise Bi<sub>2</sub>C> 3, ZnO and Ag<sub>2</sub>CO3. The concentrations of the individual compounds in the experienced tertiary combinations include Bi<sub>2</sub>O3 at 1% and 2%; and 1% and 2% ZnO; and Ag<sub>2</sub>0.5% CO3, 1% and 2%.
TABLE 8
<td>Agioj</td><td colspan="3">BÍ7O3 CuO SnOj Antimicrobial Combination</td><td>T1O2</td><td>ZnO</td><td>Reduction Log</td>
<td> 2%</td><td> -</td><td> 2%</td><td> -</td><td> -</td><td> -</td><td> 3,9</td>
<td> 2%</td><td> -</td><td> -</td><td> 2%</td><td> -</td><td> -</td><td> 3,2</td>
<td> 2%</td><td> -</td><td> -</td><td> -</td><td> -</td><td> 2%</td><td> 3,0</td>
<td> 2%</td><td> -</td><td> -</td><td> -</td><td> -</td><td> 4%</td><td> 3,3</td>
<td> 4%</td><td> -</td><td> 2%</td><td> -</td><td> -</td><td> -</td><td> 4,0</td>
<td> 4%</td><td> -</td><td> -</td><td> 2%</td><td> -</td><td> -</td><td> 3,7</td>
<td> 4%</td><td> -</td><td> -</td><td> -</td><td> 2%</td><td> -</td><td> 3,6</td>
<td> 4%</td><td> -</td><td> -</td><td> -</td><td> -</td><td> 2%</td><td> 3,7</td>
<td> -</td><td> 2%</td><td> 2%</td><td> -</td><td> -</td><td> -</td><td> 1,9</td>
<td> -</td><td> 2%</td><td> 2%</td><td> -</td><td> -</td><td> -</td><td> 2,5</td>
<td> -</td><td> 2%</td><td> 4%</td><td> -</td><td> -</td><td> -</td><td> 3,1</td>
<td> -</td><td> -</td><td> 2%</td><td> 4%</td><td> -</td><td> -</td><td> 2,4</td>
<td> -</td><td> -</td><td> 2%</td><td> -</td><td> 2%</td><td> -</td><td> 2,0</td>
<td> -</td><td> -</td><td> 2%</td><td> -</td><td> 4%</td><td> -</td><td> 2,3</td>
<td> -</td><td> -</td><td> 2%</td><td> -</td><td> -</td><td> 4%</td><td> 3,02%</td>
<td> -</td><td> -</td><td> 4%</td><td> 2%</td><td> -</td><td> -</td><td> 4,0</td>
<td> -</td><td> -</td><td> 4%</td><td> -</td><td> 2%</td><td> -</td><td> 3,9</td>
<td> -</td><td> -</td><td> 4%</td><td> -</td><td> -</td><td> 2%</td><td> 3,7</td>
<td> 2%</td><td> 2%</td><td> -</td><td> -</td><td> -</td><td> -</td><td> 3,6</td>
<td> 2%</td><td> 4%</td><td> -</td><td> -</td><td> -</td><td> -</td><td> 3,0</td>
<td> 2%</td><td> -</td><td> 4%</td><td> -</td><td> -</td><td> -</td><td> 3,8</td>
<td> 4%</td><td> 2%</td><td> -</td><td> -</td><td> -</td><td> -</td><td> 3,7</td>
Initially, the three compounds were used with equal concentrations of 1% and 2%. Combinations were also evaluated in which one of B12O3, Ag<sub>2</sub>CO<sub>3</sub> and ZnO were added at 2%, while the other compounds were added at 1%. Finally, experiments were carried out in which two compounds were added at 2% and the remaining compound at 1%. The results are collected in TABLE 9, with the log reduction again expressed against bacterial growth in the untreated sample.
The tertiary combination data show that the three components were effective when present in the ceramic enamel composition with equal concentrations of 1%. Tertiary combinations of antimicrobial agents in which an increase to 2% of one or both in the concentration of B12O3 and in the concentration of ZnO have also demonstrated effectiveness against the bacterial inoculum.
The antimicrobial activity was higher for the tertiary combination containing 2% each of Bi<sub>2</sub>O<sub>3</sub>, Ag<sub>2</sub>CO3 and ZnO.The strength of the antimicrobial activity for this combination exceeds what is expected based on the performance of the component of the individual antimicrobial agents.
It should be mentioned that the activity expectations of the binary and secondary combinations are not achieved simply by adding the log reduction values for the compounds separated at the relevant concentrations. Such an approach may be accurate in cases where the various component compounds share a common mechanism of action against the test organism.
TABLE 9
<td>BIO2O3</td><td>Antimicrobial agent ZnO</td><td>AgjCOji</td><td>Reduction Log</td>
<td> -</td><td> -</td><td> -</td><td>AT</td>
<td> 2%</td><td> -</td><td> -</td><td> 0,8</td>
<td> -</td><td> 2%</td><td> -</td><td> 0,4</td>
<td> -</td><td> -</td><td> 2%</td><td> 2,4</td>
<td> 2%</td><td> 2%</td><td> -</td><td> 0,7</td>
<td> 2%</td><td> -</td><td> 2%</td><td> 13</td>
<td> 2%</td><td> -</td><td> 4%</td><td> 3,7</td>
<td> -</td><td> 2%</td><td> 2%</td><td> 3,0</td>
<td> -</td><td> 2%</td><td> 4%</td><td> 3,7</td>
<td> 1%</td><td> 1%</td><td> 1%</td><td> 2,9</td>
<td> 2%</td><td> 1%</td><td> 1%</td><td> 2,4</td>
<td> 1%</td><td> 2%</td><td> 1%</td><td> 2,3</td>
<td> 1%</td><td> 1%</td><td> 2%</td><td> -</td>
<td> 2%</td><td> 2%</td><td> 1%</td><td> 1,8</td>
<td> 2%</td><td> 1%</td><td> 2%</td><td> -</td>
<td> 1%</td><td> 2%</td><td> 2%</td><td> -</td>
<td> 2%</td><td> 2%</td><td> 2%</td><td> 3,5</td>
However, the literature suggests that bismuth, zinc and silver 10 do not behave identically in their bacterial attack mechanisms. Without wishing to be limited by theory, in the present example, it is believed that zinc exerts its effect by disrupting bacterial respiration and the delicate balance of metals in the bacterial cell; bismuth is described as inhibiting the bacteria's ability to absorb iron; and silver is believed to act on bacterial proteins involved in the reproduction of nucleic acid.
The results demonstrate that the ceramic enamel described here showed commercially acceptable efficacy against Klebsiella pneumoniae in relation to the control. These results are exciting as they allow the use of materials in considerably less quantities than have been used so far, especially for those compounds that have previously been exploited as antimicrobial agents.
The observed results also indicate synergistic actions between the materials, providing increased levels of effectiveness with lower amounts of addition. Decreased amounts of addition reduce the cost and potential harmful effect of the compounds on the ceramic enamel.
Likewise, additional benefits are realized for the environment, in terms of both, production of refuse during the manufacture and disposal of ceramic enamel articles at the end of its useful life as a product.
As previously mentioned, antimicrobial ceramic enamel has been designed to provide built-in and durable (persistent) antimicrobial protection for a variety of ceramic articles. Consequently, the scope of the description includes ceramic articles that incorporate the present antimicrobial enamel. Such items include, but are not limited to, toilets, bidets, sinks, towel racks, soap dishes, paper holders, water control accessories (eg hot and cold water taps), and enameled ceramic tiles .
It should be understood quickly by people skilled in the art that the present composition and methods are susceptible to a wide application utility. Many embodiments and adaptations other than those described here, as well as many variations, modifications and equivalent provisions, will be apparent to or reasonably suggested to those skilled in the art by this description and the preceding description thereof, without deviating from the substance or scope.
Thus, although the present composition and methods have been described here in detail in relation to their preferred forms of realization, it should be understood that this description is only illustrative and exemplary and is made merely for the purpose of providing a complete and qualified description.
The preceding description is not intended to be constructed or to limit or otherwise exclude any other forms of realizations, adaptations, variations, modifications and equivalent provisions.
Contents21
35 members in 9 offices
Priority claims11
| Document | Office | Kind | Date |
|---|---|---|---|
| 60890666 | United States of America | – | |
| 60890673 | United States of America | – | |
| 89066607 | United States of America | P | |
| 89067307 | United States of America | P | |
| 2008054190 | United States of America | W | |
| 2008054190 | – | – | – |
| 60890666 | – | – | – |
| 60890673 | – | – | – |
| US20070890666P | – | – | – |
| US20070890673P | – | – | – |
| WO2008US54190 | – | – | – |
Members35
| Document | Office | Kind | |
|---|---|---|---|
| WO2008103621A1 | World Intellectual Property Organization (WIPO) | A1 | |
| US2009104459A1 | United States of America | A1 | |
| MX2009008853A | Mexico | A | |
| EP2118038A1 | European Patent Office (EPO) | A1 | |
| CN101622210A | China | A | |
| EG26070A | Egypt | A | |
| BRPI0807590A2This record | Brazil | A2 | |
| US2015030696A1 | United States of America | A1 | |
| US2015030861A1 | United States of America | A1 | |
| US2015030863A1 | United States of America | A1 | |
| EP2118038A4 | European Patent Office (EPO) | A4 | |
| US2016081349A1 | United States of America | A1 | |
| WO2016094484A1 | World Intellectual Property Organization (WIPO) | A1 | |
| US9434638B2 | United States of America | B2 | |
| US9446980B2 | United States of America | B2 | |
| US9446981B2 | United States of America | B2 | |
| US2016345583A1 | United States of America | A1 | |
| US2016347648A1 | United States of America | A1 | |
| US2016347649A1 | United States of America | A1 | |
| EP2118038B1 | European Patent Office (EPO) | B1 | |
| ES2630159T3 | Spain | T3 | |
| PT2118038T | Portugal | T | |
| US10045537B2 | United States of America | B2 | |
| US10045538B2 | United States of America | B2 | |
| US10045539B2 | United States of America | B2 | |
| US2018317493A1 | United States of America | A1 | |
| US2018317494A1 | United States of America | A1 | |
| US2018317495A1 | United States of America | A1 | |
| BRPI0807590B1 | Brazil | B1 | |
| US10159255B2 | United States of America | B2 | |
| US2019075800A1 | United States of America | A1 | |
| BRPI0807590B8 | Brazil | B8 | |
| US10856549B2 | United States of America | B2 | |
| US10856550B2 | United States of America | B2 | |
| US10863745B2 | United States of America | B2 |
7 legal events, as the office reported them to INPADOC
Over the term
Point at a mark for the eventEvents
| Event | Code | |
|---|---|---|
| Lapse because of non-payment of annual fees (definitively: art 78 iv lpi, resolution 113/2013 art. 12)LapsedEM VIRTUDE DA EXTINCAO PUBLICADA NA RPI 2822 DE 04-02-2025 E CONSIDERANDO AUSENCIA DE MANIFESTACAO DENTRO DOS PRAZOS LEGAIS, INFORMO QUE CABE SER MANTIDA A EXTINCAO DA PATENTE E SEUS CERTIFICADOS, CONFORME O DISPOSTO NO ARTIGO 12, DA RESOLUCAO 113/2013.B24J | B24J | |
| Lapse acc. art. 78, item iv - on non-payment of the annual fees in timeLapsedREFERENTE A 17A ANUIDADE.B21F | B21F | |
| Correction of notification of the grant [chapter 16.3 patent gazette]PRAZO DE VALIDADE: 10 (DEZ) ANOS CONTADOS A PARTIR DE 21/11/2018, OBSERVADAS AS CONDICOES LEGAIS. (CO) REFERENTE A RPI 2498 DE 21/11/2018, QUANTO AO ITEM (54) TITULO.B16C | B16C | |
| Patent or certificate of addition of invention granted [chapter 16.1 patent gazette]GrantedPRAZO DE VALIDADE: 10 (DEZ) ANOS CONTADOS A PARTIR DE 21/11/2018, OBSERVADAS AS CONDICOES LEGAIS.B16A | B16A | |
| Decision: intention to grant [chapter 9.1 patent gazette]B09A | B09A | |
| Application suspended after technical examination (opinion) [chapter 7.1 patent gazette]B07A | B07A | |
| Application suspended after technical examination (opinion) [chapter 7.1 patent gazette]B07A | B07A |
Numbers
- Publication
- PI0807590
- Publication, DOCDB
- PI0807590
- Publication, EPODOC
- BRPI0807590
- Application
- 7590
- Application, DOCDB
- PI0807590
- Application, EPODOC
- BR2008PI07590
Titles2
- Portuguese
- COMPOSIÇÃO DE ESMALTE CERÂMICO ANTIMICROBIANO, SUSBTRATO CERÂMICO ESMALTADO, E, MÉTODOS PARA FABRICAÇÃO DE UM SUBSTRATO CERÂMICO ESMALTADO E DE UMA COMPOSIÇÃO DE ESMALTE CERÂMICO ANTIMICROBIANO.
- English
- COMPOSITION OF ANTIMICROBIAL CERAMIC ENAMEL, ENAMELED CERAMIC SUSBTRATE, AND METHODS FOR MANUFACTURING AN ENAMELED CERAMIC SUBSTRATE AND AN ANTIMICROBIAL CERAMIC ENAMEL COMPOSITION.
Classification
- CPC, 24
- A01N59/16
- A01N25/08
- A01N25/34
- A61K33/245
- A61K33/30
- A61K33/38
- C03C8/14
- C03C8/20
- C03C2204/02
- C04B33/34
- C04B41/009
- C04B41/5022
- C04B41/86
- A01N59/02
- A01N59/20
- C03C2209/00
- C04B41/0072
- C04B41/4539
- C04B41/5027
- C04B41/5041
- C04B41/5049
- C04B41/505
- C04B41/91
- C04B2237/32
- IPC, 2
- C04B35 453
- C04B35 45