Patent Application
20230292756
The field of the present invention relates to an aqueous disinfectant composition for glasses.
Those who wear glasses, wheter prescription glasses or sunglasses, must clean them for a correct and optimal vision. Periodic cleaning of the glasses, especially lenses, guarantees the transparency thereof. When the lens transparency partially or completely lack, the subject's eyes tend to tire. In these cases, the stress to which the subject's eye is subjected represents an attempt to improve the vision of the external world by involuntarily adapting to it with a forced focusing system. In fact, the eye fatigue phase stops when the subject decides to polish his/her pair of glasses.
For a person driving a vehicle, glasses and especially lenses that are not carefully cleaned or simply breathed can constitute a danger to road safety.
Furthermore, dirty lenses can cause visual problems and/or worsening of pre-existing visual defects due to poor focus. Poor hygiene and cleaning of the glasses could also lead to an increased risk of developing viruses or microorganism populations, such as bacteria, mold and/or yeasts.
Dust, rain, sweat and city smog are counting causes that contribute to the daily soiling of glasses.
The pandemic caused by the SARS-CoV-2 coronavirus, which developed at the end of the year 2019, required the use not only of personal protective equipment (masks and gloves), but also of disinfectant solutions for more or less wide surfaces.
WHO guidelines (WORLD HEALTH ORGANIZATION, et al. Water, Sanitation, hygiene, and waste management for the COVID-19 virus: interim guidance, 23 Apr. 2020. World Health Organization, 2020) provide for the use in particular of:
The anti-Covid19 aqueous disinfectant solutions proposed by WHO and, in general, the known solutions for the disinfection of surfaces against viruses and/or microorganisms, such as bacteria, yeasts and/or molds, are however somewhat aggressive considering the hygiene and the cleaning of the glasses since the materials with which they are manufactured (commonly metal, plastic, acetate, titanium, polyamide or optyl) are delicate and could experience irreversible alterations.
Furthermore, the possible use of concentrated aqueous ethyl alcohol solutions is to be considered risky because these solutions are potentially flammable.
The Applicant has developed an aqueous disinfectant composition comprising the following active substance:
The aqueous disinfectant composition according to the present invention, in particular, is advantageous because it allows a correct disinfection of the glasses and lenses, due to the efficacy of all the active substance against viral, including Covid-19, and/or microbial pathogens; in addition, it fulfils its effectiveness as a disinfectant also against yeasts and molds.
The Applicant has also found that none of the active substance a)-c), and, when present, also the components d) and e) do affect the materials from which the glasses are commonly made; finally it is not flammable.
For the purposes of the present invention, the verbs “to comprise” or “to contain” are intended to define a set of elements, expressly indicating some of them, without excluding the presence of others not expressly indicated; while the term “consisting of” or “consists of” is intended to define a set of elements, indicating them all expressly, and thus excluding the presence of components not expressly listed.
By “aqueous composition” is intended a water-based composition the main component of which is water preferably between 80 and 98%, more preferably between 85 and 95% by weight on the total weight of said composition.
By “glasses” is intended an optical instrument consisting of a pair of transparent lenses, fixed to a support (frame) that keeps them fixed in front of the eyes. The glasses have the function of compensating the refractive defects of the eye (corrective glasses or commonly prescription glasses), or to protect the eyes from the harmful action of radiation or external mechanical agents (protective glasses or commonly sunglasses).
The antiviral and antimicrobial action, and the action against other microorganisms, such as yeasts and/or molds, is supported by the following pool of preserving ingredients (or preservatives), commonly used for cosmetic use:
Preferably the aqueous composition of the invention also includes d) methylchloroisothiazolinone and e) methylisothiazolinone.
Preferably the composition of the invention contains the active substance a) at concentrations ranging from 0.1 to 1%, more preferably from 0.1 to 0.6%, by weight on the total weight of the composition.
Preferably the composition of the invention contains the active substance b) at concentrations comprised between 0.005 and 0.5%, more preferably between 0.01 and 0.2%, by weight on the total weight of the composition.
Preferably the composition of the invention preferably contains the active substance c) at concentrations ranging from 0.05 to 1%, more preferably from 0.05 to 0.8%, by weight on the total weight of the composition.
When the aqueous disinfectant composition object of the present contains the active substance d), this is preferably present at concentrations comprised between 0.0005 and 0.01%, preferably between 0.0005 and 0.005%, by weight on the total weight of the aqueous disinfectant composition.
When the aqueous composition also contains the component e) this is preferably present at concentrations between 0.0001 and 0.01%, more preferably between 0.0001 and 0.001%, by weight on the total weight of the aqueous disinfectant composition according to the present invention.
Preferably, the disinfectant composition object of the invention is also cleansing, and in such a case it comprises a surfactant. Preferably this surfactant is chosen from sodium cocoamphoacetate, sodium lauryl ether sulphate and cocamidopropyl betaine.
According to a particularly preferred solution, the disinfectant and detergent aqueous composition preferably includes sodium cocoamphoacetate as surfactant.
In fact, the applicant found that, compared to the other two surfactants—sodium lauryl ether sulphate and cocamidopropyl betaine—sodium cocoamphoacetate shows the best performances in terms of foaming, degreasing capability and possible formation of post halos upon drying the lenses.
Sodium cocoamphoacetate is preferably present in the composition of the invention at concentrations ranging from 0.05 to 5%, more preferably from 0.1 to 1.5%, by weight on the total weight of the composition.
The composition according to the present invention preferably also includes a chelating agent, more preferably disodium-EDTA. According to particularly preferred solutions this chelating agent is at concentrations comprised between 0.05 and 1%, and, according to even more preferred solutions, at concentrations comprised between 0.1 and 0.6% by weight on the total weight of the composition.
The Applicant has surprisingly found that this chelating agent, disodium-EDTA, is a strong stabilizer of said aqueous disinfectant composition, since it reduces its aggressivness towards glasses, in particular in the case of mirrored sunglasses. Usually the mirroring technique of glasses involves the use of different metal ions in a mixture. Being a chelator, disodium-EDTA could, in fact, partially or totally sequester said metal ions, thus affecting the lenses mirroring of the glasses, a phenomenon which however does not occur due to the presence of this chelating agent.
o-cymene-5-ol, being fat soluble and in a needle-like form, it is scarcerly soluble in an aqueous medium, and a C2-C4 lower alcohol is preferably used as solubilizer, more preferably ethyl alcohol in amounts such as to allow solubilization in water of this active substance, and at the same time to prevent said ethyl alcohol, potentially aggressive for the materials with which glasses are commonly manufactured, from affecting the integrity thereof. Ethyl alcohol is also used in amounts such as to obtain a non-flammable aqueous disinfectant composition of the invention.
The concentration of ethyl alcohol in the composition of the invention is comprised between 1 and 20%, preferably between 1 and 15%, by weight on the total weight of the composition according to the present invention.
Said disinfectant composition can also contain stabilizing agents of methylchloroisothiazolinone and methylisothiazolinone.
These stabilizers are preferably selected from the group consisting of: magnesium chloride, magnesium nitrate and mixtures thereof.
The disinfectant composition object of the present invention as such, and even when it has cleasing properties, has high compatibility with the materials with which the glasses are manufactured; moreover, it minimizes the halos formation on the lenses of the glasses upon application, without rinsing and after drying with a specific cloth.
An example of an aqueous composition object of the invention is given below for illustrative but not limitative purposes; a formulation development study of said aqueous disinfectant composition; a study conducted to verify the effectiveness of the aqueous disinfectant composition object of the invention against the virus, in particular Covid-19.
The choice of surfactant such as to confer washing capacity was carried out on the basis of an experimental test, and selecting three different surfactant candidates available in the research and development laboratories, such as: sodium lauryl ether sulphate, sodium cocoamphoacetate and cocamidopropyl betaine.
The test involved the preparation of three different aqueous solutions for each of the aforementioned surfactants at concentrations at 1% (w/w) by weight to the total weight of the aqueous solution, and the use of mirrored sunglasses. The test consisted of immersing the sunglasses in each of the three aqueous surfactant solutions; therefore, the mirrored sunglasses were dried with a specific cloth and without further rinsing.
The test carried out assessed three different characteristic parameters of the three aforementioned aqueous solutions of surfactants at 1% (w/w): foaming, degreasing capacity, possible presence of halos after drying.
From the test described it emerged that the surfactant characterized by the best performance was sodium cocoamphoacetate.
Experimental tests were conducted to assess the compatibility of the disinfectant composition in the form of an aqueous solution with respect to the materials from which glasses are commonly manufactured (mode test (A)); a modality for the evaluation of the eventual halos formation following the use of the disinfectant composition in the form of an aqueous solution on the lens of the glasses (mode test (B)). In particular:
In order to obtain the disinfectant composition for the glasses in the form of an aqueous solution, an attempt was initially made to resolve the question of the reduced solubility in aqueous medium of the fat-soluble and needle-like shaped ingredient o-cymen-5-ol, with the use of PEG-40 hydrogenated castor oil, a solubilizing molecule widely used in cosmetics. The disinfectant composition in the form of an aqueous solution, including PEG-40 hydrogenated castor oil, was completely clear, and it was therefore decided to test its compatibility with different types of glasses using the mode test (A) and any halos formation with the mode test (B).
During the mode test (A), already after a period of soaking time of 48 hours, it was observed that the disinfectant composition in the form of an aqueous solution, including PEG-40 hydrogenated castor oil, irreversibly changed the appearance of the lens compared to “blank” sample. Even after the mode test (B), it was observed that the disinfectant composition in the form of an aqueous solution, containing the hydrogenated castor oil PEG-40, left residual halos on the lenses that were not acceptable.
As shown in
Another aspect that affects the integrity of the glasses, according to the mode test (A), and the formation of possible halos, according to the mode test (B), relates to the concentration of surfactant in aqueous composition. In particular, according to the mode test (A), the use of 4% surfactant concentrations (w/w) in a aqueous disinfectant composition (PROT. 2079) and after a 120-hour soaking time of the mirrored lens, caused a slight degradation (
Since alcohol is also a potentially aggressive solvent for the materials of which the glasses are made of, the quantity has been balanced by using the minimum necessary, and, in particular, in amounts not exceeding 20% (w/w) by weight by weight total of the aqueous disinfectant composition, for the solubilization of o-cymen-5-ol. Furthermore, this choice also allowed to obtain a non-flammable composition.
We also tried to add disodium-EDTA and it was found, quite unexpectedly, that it proved to be a strong stabilizer of the formula, making it less aggressive towards the lenses. Theoretically, EDTA, being a metal ion chelator, could have affected the mirroring of the lenses which contain mixtures of different metals, which did not happen. This appears evident in
100 μl of a 1×107 suspension colony forming units (CFU)/ml corresponding to 1×106 CFU of bacterial and fungal strains, maintained under standard conditions and grown at 37° C. or 30° C. for 16 hours, were deposited on a surface of polystyrene and exposed to 200 μL of product for 30 seconds, 1 and 3 minutes.
At the end of the treatment, the volume of microbial culture was collected, appropriately diluted and seeded in microbiological culture plates in order to evaluate the microorganism viability. The agar plates were incubated at 37° C. or 30° C. and the presence of microbial colonies monitored every 24 hours up to a maximum of 72 hours. The results are expressed as a percentage of reduction of microbial viability with reference to samples similarly prepared but not exposed to the formulation (
Similarly, tests were conducted using 100 μL of HSV-1 viral suspension. At the end of the treatment, the viral suspension was collected and diluted in a neutralization buffer in order to stop the effect of the disinfectant, is added to a monolayer of VERO cells, incubated at 37° C. for 48 hours in order to visualize the appearance of lysis plaques. The results were expressed as a percentage of reduction of infecting viral particles with reference to the control samples (
2. Experimental Results of the Antibacterial (1.1) and Antiviral (1.2) Efficacy Tests after a 1 Minute Exposure Time
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/IT2020/000044 | 5/28/2020 | WO |
