System and method for irrigation with hypochlorous acid generation

Abstract

Systems and methods for disinfecting a surface including a liquid irrigator and a hypochlorous acid generator assembly that is functionally coupled to the liquid irrigator. The liquid irrigator includes a pump mechanism and an applicator. The hypochlorous acid generator assembly is designed to produce a hypochlorous acid solution and maintain the solution within a targeted pH range in a reservoir. The pump mechanism of the liquid irrigator withdraws fluid from the reservoir and delivers an effective amount of the hypochlorous acid solution to a surface to be treated via the applicator. The hypochlorous acid solution is prepared on-site and immediately prior to application, ensuring maximum efficacy and freshness.

Description

SYSTEM AND METHOD FOR IRRIGATION WITH HYPOCHLOROUS ACID GENERATIONFIELD OF THE DISCLOSURE

[0001] The present disclosure is directed generally to disinfecting equipment and related methods for disinfecting a surface via irrigation. More particularly, the present disclosure relates to disinfecting systems, and methods including a liquid irrigator, such as an oral irrigator, and a hypochlorous acid generator assembly to produce on-site hypochlorous acid available for irrigation of a surface.BACKGROUND

[0002] In oral health care, one of the most common types of dental diseases is gum diseases, including gingivitis, periodontitis, peri-implant mucositis and peri-implantitis. The inflammation is generally caused by the buildup of pathogenic bacteria in a microbial plaque forming a biofilm rich in pathogenic bacteria. The removal of the biofilm and effective elimination of the bacteria from teeth and gum is important for effective prevention of dental disease, treatment of gum diseases, and maintenance of oral health and hygiene.

[0003] For treatment and prevention of dental disease, a variety of oral health care products like mouthwash and power toothbrushes have been developed. Currently, using an antiseptic containing mouthwash containing for example hydrogen peroxide, cetylpyridinium chloride, essential oils, or sodium hypochlorite, is a common practice in periodontal maintenance. Furthermore, in dental care, an oral irrigator or water flosser is commonly used to clean a user's teeth and gums by discharging a pressurized fluid stream onto the teeth and gums.

[0004] Conventional oral irrigators use water flossing, mouthwash product flossing, or flossing with a water solution of a preformulated oral care chemical product. The existing oral irrigators and methods for prevention or treatment of gum diseases have disadvantages in that they may have limited effectiveness on the infected area. This is especially true due to the recalcitrant nature of biofilm that has slime layers of high resistance from those pathogenicbacteria and limited availability of any safe flossing agent. To achieve the targeted disinfection and / or removal effect, it requires long treatment time, large use volume of liquid on gum and / or tooth surface, and / or avoiding eating or drinking anything for 30 minutes afterward.

[0005] Other disadvantages of known oral irrigators are, inter alia, cost, safety issues due to undesired side effects during use or accidental swallowing of mouthwash product, bad or unpleasant taste or smell, uncomfortable applications and inconvenient use.

[0006] Moreover, when an antibiotic product is frequently used for treatment of periodontal disease and peri-implant diseases and the antibiotic targets only specific bacterial molecules, there is a risk to develop drug resistance. Furthermore, higher concentrations and longer contact times may be needed for sporicidal activity.

[0007] Another disadvantage of known oral irrigators is that poor or no anti-bacterial function exists at the interior components of reservoir, pipes, and tips of water irrigators or flossing devices. Due to a tiny amount of residual water, moisture, and / or contaminant on the interior surface of those parts and lack of an effective disinfection measure, it may trigger growth of microorganisms in those areas during the life span of those devices, especially in an environment of high humidity year around.

[0008] While conventional products and techniques may function for their intended purpose, there is a continuing desire to improve disinfecting products, equipment and related methods.SUMMARY

[0009] Addressing a need for improvements in disinfecting technology, the present disclosure provides for effective disinfection and sanitization. The inventive subject matter is directed to disinfecting systems, oral irrigation systems, and related methods with integrated hypochlorous acid generation and hypochlorous acid flossing functions.

[0010] According to an example implementation of the inventive subject matter, a disinfecting system includes a liquid irrigator, including a pump mechanism and an applicator, and a hypochlorous acid generator assembly functionally coupled to the liquid irrigator. The hypochlorous acid generator assembly is adapted to produce a hypochlorous acid solution andholds the hypochlorous acid solution within a targeted pH range in a reservoir. The pump mechanism of the liquid irrigator withdraws fluid from the reservoir to the applicator to apply an effective amount of hypochlorous acid solution to a surface to be treated. The hypochlorous acid solution is prepared on-site and just prior to application.

[0011] In some embodiments, the hypochlorous acid generator assembly includes an electrolyte, a pH adjusting agent, an electrolysis unit to produce chlorine gas, and a conversion unit wherein hypochlorous acid is produced via hydration of the produced chlorine gas. In some embodiments, the electrolysis unit includes a polymer electrolyte membrane and the electrolyte is hydrochloric acid; in other embodiments, the electrolysis unit includes a cation selective membrane and the electrolyte is selected from sodium chloride, potassium chloride, and / or other non-toxic chloride salt.

[0012] In some embodiments, the targeted pH range is a pH range between about 5.5 and about 6.0. In further embodiments, the hypochlorous acid generator assembly includes a reservoir for containing the hypochlorous acid solution produced by a wet-end reaction of mixing predetermined amounts of a hypochlorite containing component and an acid containing component. In some embodiments, the hypochlorite containing component is selected from sodium hypochlorite and calcium hypochlorite. In some embodiments, the acid containing component is selected from hydrochloric acid, phosphoric acid, sulfuric acid, carbonic acid, acetic acid, citric acid, or other compatible acid. In further embodiments, the hypochlorite containing component includes a concentration of sodium hypochlorite within a range of about 0.1 % to about 5.0 % (wt. / wt.) and a concentration of hydrochloric acid within a range of about 0.1 % to about 5.0 % (wt. / wt. %).

[0013] According to another example implementation, an oral irrigation system includes an oral irrigator, an hypochlorous acid generator assembly functionally coupled to the oral irrigator, the hypochlorous acid generator assembly is adapted to produce a hypochlorous acid solution and holds the hypochlorous acid solution within a targeted pH range in a reservoir. The oral irrigator applies an effective amount of the hypochlorous acid solution to an oral surface to be treated. The hypochlorous acid solution is prepared on-site and just prior to application.

[0014] In some embodiments, the hypochlorous acid solution has a concentration of hypochlorous acid in a range of about 10 ppm to about 200 ppm. In some embodiments, the targeted pH range is a pH range between about 5.5 and about 6.0.

[0015] In some embodiments, the hypochlorous acid generator includes an electrolyte, a pH adjusting agent, an electrolysis unit to produce a chlorine gas, and a conversion unit wherein hypochlorous acid is produced via hydration of the produced chlorine gas. In some embodiments, the electrolysis unit includes a polymer electrolyte membrane and the electrolyte is hydrochloric acid; in other embodiments, the electrolysis unit includes a cation selective membrane and the electrolyte is selected from sodium chloride, potassium chloride, and / or other non-toxic chloride salt.

[0016] In further embodiments, the hypochlorous acid generator assembly includes a reservoir for containing the hypochlorous acid solution produced by a wet-end reaction of mixing predetermined amounts of a hypochlorite containing component and an acid containing component. In some embodiments, functional ingredients are added to the hypochlorous acid solution, the functional ingredients are compatible with hypochlorous acid for at least about 30 minutes at a temperature of less than about 40 degrees Celsius.

[0017] According to another example implementation, the inventive subject matter includes a method for disinfecting a surface, the method including: providing a liquid irrigator including a pump mechanism and an applicator; providing an hypochlorous acid generator assembly functionally coupled to the liquid irrigator, the hypochlorous acid generator assembly is adapted to produce a hypochlorous acid solution and holds the hypochlorous acid solution within a targeted pH range in a reservoir; activating the liquid irrigator and hypochlorous acid generator assembly; producing the hypochlorous acid solution on-site and just prior to application; activating the pump mechanism to withdraw fluid from the reservoir to the applicator; and applying an effective amount of the hypochlorous acid solution to the surface to be treated.

[0018] The inventive subject matter including a liquid irrigator with hypochlorous acid generation and flossing functions, provides numerous advantages. The disclosed subject matter overcomes issues related to stability, safety, and disinfection efficiency by using highly effective hypochlorous acid. By using the freshly produced hypochlorous acid for surface treatment, thedisclosed subject matter overcomes challenges associated with treatment of gingivitis, periodontal diseases, and peri-implant diseases, or for sanitization applications. The disclosure provides a compact device wherein mechanical means are combined with on-site chemical reactions leading to features desired for disinfecting surfaces in general and in particular for oral hygiene and dental care applications.

[0019] The disclosed technology provides a better, safer, more cost-effective, and more user-friendly oral irrigator product for successful biofilm removal and elimination that leads to better prevention or treatment of gum diseases and related tooth decay. In addition, since hypochlorous acid is a broad-spectrum disinfectant, antiseptic and deodorization agent, this "chemistry + device" technology can be readily expanded to hypochlorous- acid-based sanitization and / or deodorization applications that require shorter treatment time and safe operation, which would cover household, industrial, institutional, health care and other areas.

[0020] The disclosed devices and systems are compact and highly effective in prevention or treatment of gum diseases and can be modified for sanitization applications in other areas. Use of the disclosed devices and systems can eliminate odor-producing bacteria that grow in the mouth and cause halitosis. In some embodiments, taste is improved and if needed, flavor options can be added due to much shorter shelf-life requirements of the flossing solution. Additionally, the disclosed subject matter provides higher flexibility in preparation of hypochlorous acid solution and in shelf-life management.

[0021] In oral health care, a hypochlorous acid based oral irrigator can offer on-the-spot, highly effective, high quality hypochlorous acid based disinfection which is also inexpensive, environmentally friendly, non-toxic, safe, and an effective antimicrobial.

[0022] These and other aspects of the disclosure will be apparent from and elucidated with reference to the embodiment(s) described hereinafter.BRIEF DESCRIPTION OF THE DRAWINGS

[0023] In the drawings, like reference characters generally refer to the same parts throughout the different views. Also, the drawings are not necessarily to scale, emphasis instead generally being placed upon illustrating the principles of the inventive subject matter.

[0024] FIG. 1 is a schematic view of components of a disinfecting system with integrated hypochlorous acid generation assembly.

[0025] FIG. 2 is a schematic cross-sectional view of an electrolysis unit of an hypochlorous acid generation assembly using polymer electrolyte membrane (PEM) electrolysis of aqueous hydrochloric acid to produce Ch .

[0026] FIG. 3 is a schematic cross-sectional view of an electrolysis unit of an hypochlorous acid generation assembly using CSM electrolysis of aqueous NaCI to produce CI2 .

[0027] FIG. 4 is a flowchart of an example disinfecting method for irrigating a surface with an on-site created hypochlorous acid solution.DETAILED DESCRIPTION OF EMBODIMENTS

[0028] The following disclosure provides many different embodiments, or examples, for implementing different features of the provided subject matter. Specific examples of components and arrangements are described below to simplify the present disclosure. These are, of course, merely examples and are not intended to be limiting.

[0029] The present disclosure describes various implementations and embodiments of devices, systems and methods wherein hypochlorous acid or an hypochlorous acid solution is produced on site and is used as a disinfecting medium.

[0030] By way of example, in the area of oral applications, the disinfecting system may be an oral irrigation device or an oral irrigation system including an oral irrigator and hypochlorous acid generator assembly to remove dental plaque and food debris between teeth and below the gum line, kill oral pathogenic bacteria and plaque biofilm, eliminate odor-producing bacteria that grow in the mouth, and disinfect a user's gum, teeth, tongue, and even the whole oral cavity.

[0031] As used herein, the term "disinfecting system" refers to a device or system used for disinfecting or cleaning a surface or for treating a surface with an antiseptic. The surface to be treated can be found in or on living tissue or on inanimate surfaces. The surface to be treated can be found in a variety of settings such as household, industrial, institutional settings and in the field of health care. Within the field of oral healthcare, a surface to be treated can include surfaces of the oral cavity such as surfaces of teeth, gums, and tongue. In some embodiments, the disinfectingsystem can be an oral irrigation device with a hypochlorous acid generator assembly integrated into the oral irrigation device. In other embodiments, the disinfecting system can include a combination of a liquid irrigation device and stand-alone hypochlorous acid generator assembly that is otherwise functionally coupled to the oral irrigation device.

[0032] As used herein, the term "irrigator" and the term "irrigation" refer to the use of a pressurized solution to treat a specific surface. In oral health care applications, oral irrigation involves the direct application of a stream of water or mouthwash to help remove the microorganisms that exist on teeth, on and around gums, in the spaces between teeth and in hard- to-reach areas like periodontal pockets, implants, braces, crowns, or non-removable bridgework where brushing and flossing is difficult. Liquid irrigators may use pulsating jets of pressurized water, or non-pulsating jets of pressurized water or other solution as used in oral syringes, or a steady stream of water. The systems and devices disclosed herein using irrigation have universal application. Examples of applications wherein irrigations techniques are used to sanitize a surface may include the treatment of wounds, debridement, site soakings, topical administration of various liquid dedications as well as a variety of household or commercial applications.

[0033] The current disclosure uses hypochlorous acid as a disinfecting agent. In chlorine chemistry, with an acidity pKa - 7.53, hypochlorous acid (HCIO) is a weak acid that forms when chlorine dissolves in water, and partially dissociates, starting to form hypochlorite ions (CIO ) when the pH exceeds approximately 5.5. There is a dynamic balance among Ch molecules, HOCI molecules, and CIO- anions in aqueous hypochlorous acid solution within pH 4 to 9. When an aqueous solution's pH is over 6.0, the proportion of hypochlorous acid (HOCI) declines from virtually 100 % down to almost 0 % at pH 9.0. Between pH 4.0 to 5.5, hypochlorous acid is at its maximum level. However, solutions with pH values lower than 5.0 will begin to generate and release potentially harmful levels of chlorine gas (CI2). Hypochlorous acid decreases when the pH is below 4 (to CI2 molecules) or above 5.5 (to CIO- anions). Therefore, a pH range between about 5.0 and about 6.0 is desired because it maximizes disinfecting efficiency, since an optimal level of hypochlorous acid (HCLO > 95 %) is present and the generation and release of harmful chlorine gas in that pH range is minimized.

[0034] As used herein, the term "a targeted pH range" refers to a specific, predetermined level of acidity or alkalinity that is desired or intended for a particular solution, substance, or environment. It signifies the precise pH value that is aimed for in order to achieve a desired outcome in a chemical system. The pH value may include the outer range numbers or in between these values. In embodiments described herein, a pH in the range of about 5.0 to about 6.5 and especially a pH range between about 5.5 to about 6.0 is desired.

[0035] The term "about," as used herein, refers to variation in the numerical quantity that can occur, for example, through typical measuring and liquid handling procedures used for making concentrates or use solutions in the real world; through inadvertent error in these procedures; through differences in the manufacture, source, or purity of the ingredients used to make the compositions or carry out the methods; and the like. The term "about" also encompasses amounts that differ due to different equilibrium conditions for a composition resulting from a particular initial mixture.

[0036] The oral irrigation system is equipped to produce a hypochlorous acid solution onsite. As used herein, the term "on-site" refers to the location of use proximate to a surface that is to be treated. The hypochlorous acid solution is created by combination of chemical reactions and mechanical means shortly prior to application, without requiring storage and / or shipment of the hypochlorous acid solution.

[0037] As used herein, the term "just prior to application" or "just prior to use" refers to period of time immediately before the solution is intended to be utilized, applied, or put into action, indicating that an action or preparation is to be carried out immediately before the intended use of the end solution.

[0038] In the implementations, embodiments, and examples disclosed herein a liquid irrigator in the form of an oral irrigator is used. An oral irrigator typically uses a stream of high- pressure pulsating water intended to clean a surface in the oral cavity. Oral irrigators are often standalone units having a dedicated handle, an irrigating tip, and a reservoir that is filled with water. Some devices massage the gums using sophisticated massage heads. In some applications, irrigators can be used to inject mouthwash solution periodontal pockets using a sub-gingival nozzle.

[0039] FIG. 1 illustrates the basic components of an example oral irrigation system 10 including an oral irrigator 12 and an hypochlorous acid generator assembly 14. Oral irrigation system 10 provides disinfecting action by combining pulsating liquid flossing with freshly produced hypochlorous acid solution. The actual size, shape, appearance, necessity of each component can be minimized, added, deleted, or modified to make it a fit, functional, and attractive device for commercial purposes. The Figures are schematic and not drawn to scale.

[0040] In the example of FIG. 1, hypochlorous acid generator assembly 14 includes an electrolysis unit 16 and a conversion unit 18. The oral irrigation system 10 includes an integrated power supply 20. In some embodiments, power supply 20 can also be designed as battery powered.

[0041] Electrolysis unit 16 includes an electrolysis membrane 50. In some embodiments, membrane 50 is a polymer electrolyte membrane (PEM). In other embodiments, membrane 50 is a cation selective membrane (CSM) electrolysis unit. In further embodiments, the electrolysis unit may include an electrolyte membrane 50 made of homogenous or heterogenous, inorganic, polymeric, or hybrid of inorganic and polymeric, but ion-selective membranes. In some embodiments, the electrolysis unit can further include an accessories assembly to produce chlorine gas for generation of hypochlorous acid in the conversion unit.

[0042] Conversion unit 18 allows conversion of chlorine gas to hypochlorous acid and includes a reservoir 22, such as a flossing reservoir, tank, chamber, cell, or cup, in which chlorine gas from the electrolysis unit arrives and is converted to hypochlorous acid via reaction of chlorine with water and a pH adjustment agent. Reservoir 22 also holds the resultant produced hypochlorous acid water solution with a pH in the range of about 5.5 to about 6.0.

[0043] The hypochlorous acid generator assembly further includes an electrolyte solution 24 added into the electrolysis unit 16 and water solution with a pH adjusting agent 44 added into reservoir 22. In some embodiments, functional ingredients such as flavoring, remineralization, and desensitizing agents may be added into reservoir 22 when desired.

[0044] Oral irrigator 12 has a housing assembly 26 which includes a pump mechanism 28, pipes 32 and wires 34 to functionally interconnect the components of oral irrigation system 10, and an applicator 30 in the form of a nozzle or tip with handle.

[0045] Oral irrigation system 10 further includes a control unit 36 to control the electrolysis process. In some embodiments, control unit 36 may be coupled to one or more sensors, such as temperature sensor 38, CI2 gas sensor 40, and pH sensor 42. In some embodiments, additional sensors, such as a potentiometer and / or pressure sensor, may be provided and functionally coupled to the control unit, electrolysis unit, and hypochlorous acid conversion tank. In other embodiments, batteries, motors, actuators, and other functional elements can be provided.

[0046] Applicator 30 of oral irrigator 12 allows for the withdrawal of the generated hypochlorous acid solution from reservoir 22 and precise application to the surface to be treated, ensuring effective disinfection and eliminating the need for pre-prepared solutions and ensuring freshness and potency. In some embodiments, the dental flossing time for applications with the disclosed devices and systems can be easily set from 30 seconds to 2 minutes to achieve its desired functions.

[0047] Example 1 - Embodiment using on-site production of hypochlorous acid by polymer electrolyte membrane (PEM) electrolysis

[0048] In one implementation of an oral irrigation system, hypochlorous acid is produced on-site by PEM electrolysis of hydrochloric acid and hydration of chlorine gas to hypochlorous acid via an integrated hypochlorous acid generator. As described above, an integrated hypochlorous acid generator assembly may be embedded in a housing assembly and a reservoir of the oral irrigation unit. The hypochlorous acid generator is adapted to produce fresh, on-site hypochlorous acid of 10-200 ppm by PEM electrolysis with desired pH range of about 5.5 to about 6.0.

[0049] A. PEM electrolysis of hydrochloric acid to produce chlorine gas

[0050] FIG. 2 illustrates the workings of an example embodiment using a PEM electrolysis unit 200 performing electrolysis of aqueous hydrochloric acid to produce chlorine gas. PEM electrolysis unit 200 uses a thin semipermeable membrane 202 that conducts protons while acting as an electronic insulator and reactant barrier to chlorine and hydrogen gas. In the example embodiment, PEM membrane 202 can have a thickness in the range of about 100 to about 300 pm. PEM membrane 202 can be made of perfluorinated sulfonated membrane (PFSA) such as Nation™ 117, or other suitable material which only allows protons to pass through duringelectrolysis. With PEM as gas crossover barrier to chlorine and hydrogen gas and conducting protons while acting as an electronic insulator, PEM electrolysis of hydrochloric acid results in a high product gas purity of chlorine for the follow-up hydration of chlorine gas to hypochlorous acid in the conversion unit of the integrated hypochlorous acid generator.

[0051] As illustrated in FIG. 2, the PEM electrolysis of hydrochloric acid to produce chlorine gas proceeds according to the following equations at the cathode and anode respectively:Cathode: 2 H+(aq) + 2 e- -> H2 (g) Anode: 2 Cl" (aq) -> CI2 (g) + 2 e-

[0052] The overall electrolysis process equation reads:

[0053] In the next step, hydration of chlorine gas from PEM electrolysis of the hydrochloric acid process to hypochlorous acid is processed according to the following reaction:CI2+ H2O ^ HCIO + HCI . (2)

[0054] Chemical equations (1) and (2) show that for each mole of HCI electrolyzed, only one half mole of HCIO is produced in the hydration reaction, assuming 100 % yield and hydration rate. When assuming equal volumes and 100 % yield of the whole process, in order to produce 10-200 ppm hypochlorous acid from the electrolysis process of hydrochloric acid and then a follow-up hydration of the produced chlorine gas in water to hypochlorous acid, a minimum concentration of 13.90-278.08 ppm HCI (0.00139-0.02781 %, wt. / wt.) as starting electrolyte concentration is needed. However, due to less than 100 % yield (which is a desired electrolysis reaction at the anode, i.e., generation of chloring gas only) and much smaller volume of the PEM cell for the HCI electrolyte solution (compared to the conversion unit reservoir for conversion of chlorine gas into hypochlorous acid) in practical operation, a higher HCI electrolyte concentrationthan the minimum concentration in the PEM cell may be preferred. Based on safety, quality, and process optimization consideration, the electrolyte concentration used in the PEM cell could be 0.05-15.00 % HCI solution, and 0.05-5.00 % HCI would be preferred as the starting electrolyte for this PEM process.

[0055] In some embodiments, the volume of electrolyte HCI solution in the PEM cell could be 5 ml to 50 ml, while the volume of the conversion unit reservoir for conversion of chlorine gas into hypochlorous acid is within the 100 ml-1000 ml range, preferably around 500 ml.

[0056] In some embodiments, for the PEM cell, electrodes of metal, graphite and semiconductor material could be used. The choice of a suitable electrode depends on the chemical reactivity between the electrode and electrolyte and manufacturing cost. In some embodiments, when non-reactive anodes are desired for electrolysis, graphite, platinum, or platinum film coated metal rods can be chosen. Cathodes may be made of the same material, or they may be made from a more reactive one since anode wear is greater due to oxidation at the anode.

[0057] In some embodiments, the PEM cell can be made of titanium, ceramic, glass, acid and chlorine resistant plastic, material having acid and chlorine resistant liner or coating on top, or other materials having non-reactive properties to hydrochloric acid and chlorine.

[0058] Optionally, in some embodiments, in the anode chamber or in both chambers of the PEM cell, an acid and salt-resistant mini-mixer, magnetic or non-magnetic, could be used to slowly circulate the electrolyte inside the chamber to enhance the electrolysis.

[0059] PEM electrolysis offers advantages such as operating at high current densities, having an electrical efficiency of around 80 %, high product purity, and durability. It is known that enlarged electrode surface area facilitates the electrolysis reaction. Any approach, such as microporous structure of electrode, to increase the total surface area of the electrode without compromising its durability could be used. The choice of operational electrode potential should be based on specific empirical yield of the PEM electrolysis device to produce about 500 ml of 10- 200 ppm hypochlorous acid in about 2 to 5 minutes, or maximally about 10 to 15 minutes for the intended flossing or disinfection applications.

[0060] The electrode potential of the electrolysis unit can be determined and optimized for producing X ml of Y ppm hypochlorous acid in T minutes. By using Faraday's First Law ofElectrolysis (3), Ohm's Law (4), and the Current Law in conducting media (5) as below, the theoretically approximate or minimum electrical potential difference across the PEM electrodes in units of volts can be determined as in equation (7):

[0061] Faraday's First Law of Electrolysis:?n=(Q* / l ) / (96485 (Coulomb*mol4)*n) . (3) wherein m: the mass of the substance produced at the electrode (in grams).Q: the total electric charge that passed through PEM cell solution (in coulombs), n: the valence number of the substance as an ion in solution (electrons per ion). M: the molar mass of the substance (in grams per mole).

[0062] Ohm’s Law: l-V / R . (4) whereinI: the current through the PEM cell solution in units of amperes.V: the potential difference measured across the electrodes in units of volts.R: the resistance of the PEM cell in units of ohms.

[0063] The Current Law in conducting media:I=Q / t . (5) whereinI: the average current through the PEM cell solution in units of amperes Q: the electric charge transferred through the PEM cell solution over an electrolysis time t, in coulombs. t: the electrolysis time, in seconds.

[0064] From equations (3), (4), and (5), the potential difference can be derived:V= (m*96485*R) / (M*t) . (6)

[0065] Thus, based on equation (6) and equation (1) and (2), the minimum electrolysis potential difference can be calculated:Minimum Electrolysis Potential Difference (Vminimum) across the PEM electrodes:Vminimum = 2*96485* / ?* *K / (M*106*T*60) . (7)whereinR: the resistance of the PEM cell in units of ohmsX and Y: X ml of Y ppm hypochlorous acid (HCIO) produced M: the molar mass of hypochlorous acid (52.46 g / mol) T: PEM electrolysis time in minutes to produce CI2 gas needed for the X ml of Y ppm HCIO under 100 % efficiency.

[0066] In general, in PEM electrolysis, voltage losses may occur due to PEM cell Ohmic losses, activation losses and / or mass transport losses. All those voltage losses make the final operational electrical potential difference (voltage) across the PEM electrodes higher than the Minimum Electrolysis Potential Difference Vminimum. Since it is related to specific PEM cell design specifications, the actual required working PEM voltage application is determined by the specific design of the PEM cell. Considering approximately 80 % electrical efficiency of the PEM cells, the working PEM voltage could be around 1.25 times or more of the Vminimum. Since the electrical resistance of the PEM cell can be determined for a known PEM cell with a specific design specification, calculating the Vminimum will help in determining what the needed working PEM voltage or power input for a specific required PEM electrolysis unit needs to be.

[0067] In some embodiments, the leftover solution in the anode chamber of the PEM cell after each electrolysis production is completed may still predominately be hydrochloric acid but with reduced concentration. In some embodiments, with precise process control via a potentiometer and a pH meter on the electrolysis unit and the follow-up hydration of chlorine gas in the conversion unit, the remaining HCI solution in the PEM cell can continue to be the starting raw material for the electrolysis to produce chlorine gas for next batch of HCIO solution production, until the remaining HCI in the solution runs out to produce enough quantity of chlorine gas to generate designed HCIO solution at the desired ppm.

[0068] B. Hydration of chlorine gas from PEM electrolysis of hydrochloric acid process to hypochlorous acid

[0069] In an example embodiment, hydration of chlorine gas from the PEM electrolysis to hypochlorous acid is accomplished in the conversion unit, according to the following reaction:Ch (gas) + H2O HCIO (aq.) + H+(aq.)+CI (aq.) . (8)

[0070] Based on equation (8), it can be deduced that for the generation of 10-200 ppm hypochlorous acid via hydration reaction of chlorine gas, approximately 6.95-139.04 ppm (0.000695-0.013904 % (wt. / wt.), or 0.0001906-0.0038124 M) hydrochloric acid (HCI) would be generated as a byproduct. Since by calculation, the pH of the 6.95 ppm (or 0.0001906 M) HCI solution is pH 3.72 and the pH of the 139.04 ppm HCI solution is pH 2.42, respectively, the product pH range of 10-200 ppm hypochlorous acid in the hydration reaction of chlorine gas is within pH 2.42-3.72. That pH would not lead to significant hypochlorous acid generation. However, since HCIO is a weak acid with pKa - 7.53, if a precise amount of caustic pH adjustment agent like caustic soda (NaOH) is pre-added into the hydration water solution for producing a specific targeted ppm of HCIO, the hypochlorous acid can be produced very quickly afterwards according to the hydration equation (8) due to the neutralization (see equation (9) as shown in below) by preadded alkaline, which removes the excess HCI but leaving only needed HCI for pH control in Equation (8), and the final pH of the produced hypochlorous acid can meet the desired pH range of about 5.0-6.5, especially the pH range of about 5.5-6.0 for human oral health applications.

[0071] In some embodiments, when a caustic pH adjustment agent like NaOH is pre-added in the chlorine gas hydration solution, the following acid-base reaction occurs subsequently with acid from reaction (8) to remove the excess HCI produced in equation (8):H+(aq., from dissociated excess HCI) + OH- (aq., from dissociated NaOH) ) H2O . (9)

[0072] Reaction (9) will dramatically move reaction (8) dynamics completely to its right side by neutralizing the excess HCI acid and produce HCIO much faster.

[0073] Reactions (8) and (9) are performed at room temperature or with colder water, with mild, controlled, and designed alkalinity. For HCIO stability purpose, the final HCIO solution is preferably kept below 40 °C. The hydration reaction (8) of chlorine gas with slightly alkaline water to produce hypochlorous acid is a heterogeneous, gas-liquid reaction which occurs on the surfaces. The rate of reaction increases as the gas-liquid interface surface area does. That isbecause more molecules of the liquid are exposed and can be hit by reactant gas molecules. Thus, any measure or approach in the conversion unit to safely increase the reaction interface surface area of gas and slightly alkaline water solution will facilitate fast and efficient conversion of chlorine gas to hypochlorous acid in about 2-5 minutes, or maximally 10-15 minutes.

[0074] The following calculation example and Table 1 are provided for the understanding of how in some embodiments a precise amount of caustic pH adjustment agent is determined for a preselected and desired pH of the hypochlorous acid solution. For example, the molar concentration of a pH 5.0-6.0 HCI solution is 0.00001-0.000001 M. Only 0.00001-0.000001 M (equal to 0.3647 to 0.03647 ppm) of HCI is needed for the creation of pH 5.0-6.0 acidity range. Thus, to produce a 10-200 ppm hypochlorous acid solution of pH 6.0, in production, 6.91-139.00 ppm of HCI generated from the hydration reaction (2) needs to be neutralized by the pre-added alkaline pH adjustment agent like NaOH. That is equal to NaOH being pre-added at a 7.58-152.45 ppm dosage level in the hydration water. Similarly, to precisely produce a 100 ppm HCIO solution of pH 5.8 (pH of 0.0578 ppm of HCI solution is 5.8), it requires about (69.50 minus 0.0578) - about 69.44 ppm of HCI generated from the hydration reaction (2) or (8) to be neutralized by the preadded alkaline pH adjustment agent. When NaOH is used, it means pre-addition of NaOH at the hydration water at about 76.18 ppm dosage level.

[0075] According to possible embodiments, Table 1 lists dosage and amounts, in milligrams, of NaOH needed for the production of 500 ml of 10-200 ppm HCIO solution with pH 5.8.

[0076] TABLE 1

[0077] In some embodiments, a pH sensor and a potentiometer sensor are embedded in the hydration reservoir of the conversion unit to monitor and / or control the production process of hypochlorous acid solution with desired pH range. In some embodiments, an acid and oxidizerresistant mini-mixer can be used to slowly circulate the solution inside the conversion reservoir to enhance the Ch hydration and HCIO solution production and homogenization.

[0078] In further embodiments, a HCIO oxidation reduction potential sensor can be installed in the hydration reservoir of the conversion unit and run along with the electrolysis program of the control unit to make sure the targeted ppm of HCIO is produced. In other embodiments, a chlorine gas sensor can be installed above the liquid surface of the conversion unit to monitor the safety of the HCIO production process. In some embodiments, programmed with the control unit, other sensors can also be used to monitor and / or control process variables like temperature, pressure, and the like.

[0079] In some embodiments, a suitable caustic pH adjustment agent can be alkali earth or metal hydroxides, particularly sodium hydroxide and / or potassium hydroxide, or other suitable compound like sodium carbonate. In some embodiments, an acidic pH adjustment agent can be hydrochloric acid, phosphoric acid, sulfuric acid, or acetic acid.

[0080] With a freshly generated HCIO solution having a pH in the range of about 5.5 to about 6.0, flossing and / or disinfecting of teeth, gum, and oral cavity can be accomplished in an efficient and straightforward manner. Generally, depending on the required use or treatment time, a low concentration of 10-100 ppm of HCIO solution is good for flossing while a high concentration of 100-200 ppm is faster and stronger for disinfection.

[0081] In some embodiments, flavoring agents, in particular substances that trigger the sense of taste and / or smell, can be used to improve the consumer perception and experience in treatment or application by either adding flavor to an otherwise flavorless product or to mask any undesirable flavors. Due to the strong oxidizing power of hypochlorous acid, if a flavor is needed, flavor agents, such as menthol or peppermint oil, can be added into the water in the container of the conversion unit at a 10-1000 ppm dosage level. When desired, remineralization agents via amorphous calcium phosphate formation, like water-soluble phosphate salts sodium diphosphate and calcium salts like calcium nitrate can also be added into the hypochlorous acid water solution after the HCIO generation, since pH 5.5-6.0 can keep both remineralization salt mildly water soluble. Potassium chloride might also be added into the final HCIO solution for desensitizing function if needed in treating severe gingivitis or periodontitis.

[0082] Some embodiments using on-site production of hypochlorous acid by PEM electrolysis of hydrochloric acid and hydration of chlorine gas to hypochlorous acid can be integrated in the oral irrigation system described above. According to an embodiment, the oral irrigation system includes a base unit that provides support to parts of the oral irrigator, a fluid supply, the HCIO conversion and flossing reservoir, a pump, tubes, a handle and handle support, applicator in the form of nozzle or tip, actuators, and flow control parts. Such a system can be integrated with the system of hypochlorous acid generation in the oral irrigator. The disclosed devices and systems can further include pumping means to withdraw fluid from the HCIO conversion and flossing reservoir, via draw tube(s), and discharge the fluid to the tip or nozzle and after that, to the application areas. When needed, fresh hypochlorous acid solution at higher ppm with desired pH is produced in a few minutes before starting of the dental treatment or sanitization operation. Several irrigation operation modes and steps may be provided similar to the design of existing oral irrigators.

[0083] In some embodiments, the generated HCIO solution can be transferred and dispensed onto a surface by syringe, spray bottle, pipette, tray, strips, wipes, or other suitable devices or materials. In addition, any tray or strip that is hypochlorous acid compatible could be used to carry the final solution to the targeted surface in prevention or treatment of periodontaldisease and peri-implant diseases. Any periodontal applicator can be used to gently deliver the generated HCIO medicament solution and to rinse deep below the gumline.

[0084] Example 2 - Embodiment using on-site production of instant hypochlorous acid by Cation Selective Membrane (CSM) Electrolysis

[0085] Another implementation of an oral irrigation system, produces on-site instant hypochlorous acid by Cation Selective Membrane (CSM) electrolysis of sodium chloride, potassium chloride, and / or other non-toxic chloride salt, followed by hydration of chlorine gas to hypochlorous acid via integrated hypochlorous acid generator.

[0086] FIG. 3 shows a CSM electrolysis unit 300 illustrating electrolysis of aqueous NaCI to Ch. This implementation uses a salt tolerant, cation-selective membrane (CSM) 302, also called cation exchange membrane (CEM) to perform electrolysis and to generate chlorine gas with high purity. This implementation is similar to the PEM electrolysis implementation described above in that it involves the same hydration process of chlorine gas to produce hypochlorous acid via integrated hypochlorous acid generator. The same precisely controlled, slightly alkaline water is used for the chlorine gas hydration reaction to produce 10-200 ppm HCIO solution in the pH range of about 5.5 to about 6.0. The construction materials and design of the CSM electrolysis cell, hydration reservoir, as well as the pH adjustment agent can be similar to the embodiments described above using the PEM membrane. Optionally, in some embodiments, agents such as flavor agents, remineralization agents, and desensitizing agents can be added. Additionally, the electrolysis and hydration temperature, and the flossing / irrigation system used in this implementation can be the same as in the implementation described above. The oral irrigator's HCIO solution dispensing system and control unit of the dispensing are also the same as described above.

[0087] However, compared to the implementation using PEM electrolysis described above, CSM electrolysis includes several differences. For example, the membrane in CSM cell is different than the membrane in PEM cell. The CSM is salt tolerant and made of negatively charged matter in the membrane shape, which rejects negatively charged ions and allows positively charged ions like H+, Na+, K+, and the like to pass through while the PEM membrane only allows proton ions (H+) to flow through. In composition, the CSM includes groups of negative charges, forexample single bond PCh", single bond COO" and single bond CeF O" in the backbone of the membrane. In construction, a CSM is a semipermeable membrane, of about 100-300 pm, and various types of materials could be used such as Nation™, Ultrex, and membranes including polystyrene and divinylbenzene with a sulfuric acid group.

[0088] FIG. 3 illustrates an example embodiments of CSM electrolysis of hydrochloric acid to produce chlorine gas. In the example embodiment, the starting materials in CSM electrolysis can be sodium chloride, potassium chloride, and / or other non-toxic chloride salt.

[0089] For example, when table salt is used, production of chlorine gas proceeds according to the following equations:Cathode: 2 H2O + 2 e" - H2(g) + 2OH"Anode: 2 Cl" (aq) -> Cl2(g) + 2 e"

[0090] At the CSM cell, the CSM membrane at the center allows the sodium ions (Na+) to pass to the cathode chamber where they react with the hydroxide ions to produce caustic soda (NaOH, in ions form of Na+and OH- in the cathode chamber solution). The overall reaction for the electrolysis of a table salt solution is:Overall electrolysis process equation: 2NaCI + 2H2O -> Cl2+ H2+ 2Na++ 2OH" . (10)

[0091] In chlorine chemistry, equations (10) and (8) show that for each mole of NaCI electrolyzed, only one-half mole of HCIO is produced in the follow-up hydration reaction, assuming 100 % yield and hydration rate. When assuming equal volumes and 100 % yield of the whole process, theoretically it is known that in order to produce 10-200 ppm hypochlorous acid from the process of electrolysis of aqueous sodium chloride and then a follow-up hydration of the produced chlorine gas in slightly alkaline water to hypochlorous acid, a minimum concentration of 22.27- 445.60 ppm NaCI (0.00223-0.04456 %, wt. / wt.) as starting electrolyte concentration is needed. Similarly, due to less than 100 % yield (100 % yield is a desired electrolysis reaction at the anode, i.e., generation of chloring gas only) and much smaller volume of CSM cell for the NaCI electrolytesolution (compared to the conversion unit tank for conversion of chlorine gas into hypochlorous acid) in practical operation, it is preferred to have a higher NaCI electrolyte concentration than the minimum concentration in the CSM cell. The electrolyte concentration used in the CSM cell could be 0.05-20.00 % NaCI solution, and 0.05-5.00 % NaCI would be preferred as the starting electrolyte for this CSM electrolysis process. The volume of electrolyte NaCI solution in CSM cell could be 5 ml to 50 ml, while the volume of the conversion unit tank for conversion of chlorine gas into hypochlorous acid is within 100 ml-1000 ml, preferably around 500 ml.

[0092] After CSM electrolysis, in the example embodiment, the leftover solution in the cathode chamber and anode chamber of the CSM cell are predominately a NaOH solution and a solution of NaCI, respectively, compared to the predominately H2O in the cathode chamber and HCI leftover solution in the anode chamber of the PEM cell embodiments described above.

[0093] In some embodiments, depending on the application requirements, the NaOH produced in the cathode chamber of CSM cell might be used as a self-produced alkaline pH adjustment agent for the hydration of chlorine gas in the conversion unit to produce HCIO solution. Its concentration and dosage can be measured and calculated, based on the required NaOH dosage that is pre-added in the chlorine hydration water to produce 500 ml of a 10-200 ppm HCIO solution with designed pH value. In other embodiments, with a pH test paper in hand, a simple portable device is envisioned to produce a low cost but effective and quality HCIO solution in the open air for disinfection / sanitization purposes in poverty stricken or war-torn regions.

[0094] In some embodiments, the leftover NaCI solution in the anode chamber of CSM cell can easily be discharged into a sink drain and be flushed with tap water. Similarly, in some embodiments, the NaOH solution produced in the cathode chamber of CSM cell can easily be discharged and flushed with tap water to the sink drain. Since the volumes and concentrations of those electrolysis leftover solution are very small, the expected impact on the environment is minor.

[0095] In some embodiments, by simply mixing 1 / 3 or more, to the whole NaOH solution produced in the cathode chamber of CSM cell with the HCIO solution produced in the conversion tank, a low ppm, fresh degreasing and disinfecting alkaline bleach solution can easily be createdfor household, industrial, institutional applications. In one example embodiment, a portable device producing fresh consumer-grade bleach solution using less than a tablespoon of table salt, plus water and electricity (AC, DC, or battery) can be provided.

[0096] Example 3 - Embodiment using on-site production of instant hypochlorous acid by wet-end chemical reaction

[0097] In another implementation of an oral irrigation system, hypochlorous acid can be produced on-site by reaction of carbonic acid, hydrochloric acid, phosphoric acid, sulfuric acid, carbonic acid, acetic acid, citric acid, or other compatible acid with a low concentration (< 12.5 %, wt. %) of sodium hypochlorite or calcium hypochlorite solution according to a predetermined mixing ratio, dosage, safety requirement, and procedure. The wet-end reaction can be carried out in a hypochlorous acid generator assembly of an oral irrigator or as an accessory generator part of the oral irrigator.

[0098] The ingredients for the wet-end reaction of the described example embodiments are readily available. Preferably, each functional ingredient is compatible with hypochlorous acid at least in short term, i.e., more than or equal to 0.5 hours, at a temperature below or equal to 40 °C.

[0099] To accomplish the reaction safely and to avoid any harmful chlorine gas generation, several things need to be done properly. In some embodiments, the alkalinity and concentration of sodium hypochlorite or of the calcium hypochlorite solution in its container or cartridge should be accurate and precisely determined before mixing. For example, to keep the hypochlorite solution stable, most commercial sodium hypochlorite products are at a pH range of about 12.0 to about 13.0 with around 0.2-1.0 % excess caustic soda (NaOH) before dilution. The alkalinity should be known so that the accurate amount of acid can be determined to neutralize the excess caustic soda and make the final pH of the mixed solution stay in the pH range of about 5.5 to about 6.0. The alkalinity can be determined by standard test methods such as ASTM D2022 or other suitable methods.

[0100] In the example embodiment, concentration of hydrochloric acid, phosphoric acid, sulfuric acid, carbonic acid, acetic acid, citric acid, or other compatible acid in its container or cartridge should be accurately and precisely controlled by suitable methods before mixing.

[0101] Additionally, in the example embodiment, for safety purposes, the mixing of the two components, hypochlorite and acid respectively, should be carried out precisely by first adding the acid component into the water of the oral irrigator's reservoir and mix well, then adding the hypochlorite component into the solution the oral irrigator's reservoir from the previous step, and finally mixing well to complete reactions (11) and (12) to generate HCIO solution. Reactions (11) and (12) should be done at room temperature or lower. The final HCIO solution should be kept below 40 °C for HCIO stability purpose.

[0102] Two wet-end chemical reactions occur during the HCIO generation process:

[0103] Step 1: Acid-base neutralization to neutralize the excess base in hypochlorite solution to water:OH- (aq., from caustic soda) + H+(aq., from acid) H2O . (11)

[0104] Step 2: Acidification of hypochlorite ions to hypochlorous acid:CIO’ (aq.) + H+(aq., from acid) HCIO . (12)

[0105] In some embodiments, extra acid as pH adjustment agent is provided to create the designed pH of solution. For example, in some embodiments, an extra 0.0578 ppm of HCI dosage of HCI can make the final HCIO solution at pH 5.8.

[0106] In the example embodiment, the preferred hypochlorite compound in equation (11) is sodium hypochlorite. It is well known that the shelf-life of sodium hypochlorite solution is sensitive to its HCIO concentration and storage temperature at a pH range of about 12 to about 13. A lower concentration of sodium hypochlorite with a pH of about 12 to about 13 can last very long under room temperature storage condition. Considering a 10-200 ppm concentration of HCIO solution is used for effective treatments, the recommended concentration of sodium hypochlorite as ingredient supplied in a cartridge or container is within the range of 0.1 %-5.0 % (wt. / wt. %). In some embodiments, 0.1 %-1.0 % strength may be preferred in products with long shelf-life and safety where refrigeration storage condition is not used. The preferred acid species in equation(11) and (12) is hydrochloric acid. For safety purpose, handling of hydrochloric acid of high concentration (>5.0%, wt. / wt.), especially "fuming" hydrochloric acid (37 %, wt. / wt.) is not necessary. In some embodiments, the preferred concentration of hydrochloric acid is 0.1 %-5.0 % (wt. / wt. %) HCI.

[0107] In the alternative, in some embodiments, other hypochlorites such as calcium hypochlorite can be used, preferably solutions of a soluble hypochlorite. In some embodiments, other alkaline and hypochlorite compatible functional and / or inert ingredients may be present. In further embodiments, extra pH modifying agent may be formulated to control the hypochlorite solution pH to be within the range of about 12.0 to about 13.0. In some embodiments, the dosage of alkaline composition of hypochlorite solution includes 0.01-0.5 molar commercial potassium hydroxide or caustic soda. In some embodiments, in the final produced HCIO solution, potassium chloride may be present for de-sensitizing function. In other embodiments, calcium salts like calcium nitrate can also be added into the acid component or the final hypochlorous acid water solution, and sodium diphosphate may be present in the hypochlorite component or the final hypochlorous acid water solution for remineralization purpose. Flavoring agents, such as menthol or peppermint oil, could be added into the final HCIO solution before use, if desired.

[0108] By way of example, below is a calculation method and a preparation method of a 500 ml of 10-200 ppm HCIO solution with pH 5.8 according to an embodiment using the wet-end chemical reaction approach and using 0.5 % (wt. / wt. %) of NaCIO with 0.2 % (wt. / wt. % excess caustic soda (NaOH) and 1.0 % (wt. / wt. %) HCI solution.

[0109] In this example, the calculation method to find the amount of "0.5 % of NaCIO with 0.2 % excess NaOH" and 1.0 % HCI solution needed proceeds as follows: 500 ml of 10-200 ppm HCIO needs conversion of 7.095-141.898 mg (0.007095-0.141898 gram) of NaCIO to HCIO via conversion reaction equation (12), assuming 100 % conversion rate. Then, 7.095-141.898 mg (0.007095-0.141898 gram) of NaCIO needs 1.419- 28.380 grams of "the 0.5 % of NaCIO with 0.2 % excess caustic soda" to provide the needed CIO- ions in 500 ml of 10-200 ppm HCIO. Accordingly, 7.095-141.898 mg (0.007095-0.141898 gram) of NaCIO needs 3.476-69.519 mg (0.003476- 0.069519 grams) of HCI to convert it into HCIO in equation (12). In 1.419-28.380 grams of "the 0.5 % of NaCIO with 0.2 % excess caustic soda", the amount of excess caustic soda is 0.002838-0.056760 grams (2.838-56.760 mg), which requires 0.002588-0.051751 grams (2.588-51.751 mg) of HCI to neutralize it to pH 7.0 via reaction equation (11). An extra amount of about 0.0578 x 500 / (1,000,000) - 0.0000289 gram (0.0289 mg) of HCI is needed as pH adjustment agent to make the final 500 ml of 10-200 ppm HCIO solution at pH 5.8. Totally, the needed acid HCI is about (0.003476+0.002588+0.0000289 = 0.006093) to (0.069519+0.051751+0.0000289 = 0.1212989) grams (or 6.093-121.299 mg), which means it needs around 0.609-12.130 grams (about 609- 12,130 mg) of 1 % HCI solution.

[0110] In this example , the preparation method to arrive at a 500 ml of 10-200 ppm HCIO solution with pH 5.8 includes: first add 0.609-12.130 grams (609-12,130 mg) of 1 % HCI solution into the oral irrigator's reservoir already containing around 450 ml water of room temperature and mix well; then add 1.419-28.380 grams of the 0.5 % of NaCIO with 0.2 % excess caustic soda into the solution the oral irrigator's reservoir from previous step, mixing well; finally add a little more water into the reservoir until it reaches 500 ml mark and mix well to generate 500 ml 10- 200 ppm of HCIO solution with pH 5.8.

[0111] FIG. 4 is a flowchart of an example method for irrigating a surface. It should be appreciated that the order of steps shown in FIG. 4 is exemplary, and the steps may be performed in other orders or combinations. Method 400 can use the systems, arrangements, and components of any of the implementations, embodiments, or examples described herein.

[0112] At step 410, a liquid irrigator is provided. The liquid irrigator includes a pump mechanism and an applicator.

[0113] At step 420, an hypochlorous acid generator assembly is provided. The hypochlorous acid generator assembly is functionally coupled to the liquid irrigator, the hypochlorous acid generator assembly is adapted to produce a hypochlorous acid solution and holds the hypochlorous acid solution within a targeted pH range in a reservoir.

[0114] At step 430, the liquid irrigator and hypochlorous acid generator assembly are activated.

[0115] At step 440, the hypochlorous acid solution is produced on-site and just prior to application.

[0116] At step 450, the pump mechanism is activated to withdraw fluid from the reservoir to the applicator.

[0117] At step 460, an effective amount of the hypochlorous acid solution is applied to the surface to be treated.

[0118] The above described chemical ingredients, such as HCI, NaOH or KOH, KNO3, peppermint oil, CafNOsh, NaH2PO4, NaCI, NaCIO, and the like, can be supplied as cartridges in container of standard concentration solutions.

[0119] With capacity scale up, the present disclosure can be designed into a mobile hygiene atomizer and placed at those facilities. In addition, the present disclosure can be modified into a specific, portable, hypochlorous acid-based household deodorization device with addition of fragrance in its final dispensed solution from its atomization part.

[0120] Furthermore, in some implementations, a device can be made by partly replacing the water in the composition with alcohol, such as ethanol or isopropanol, while keeping the hypochlorous acid concentration (<200 ppm) in the final solution safe enough for human contact. As hypochlorous acid is a broad-spectrum disinfectant, antiseptic and deodorization agent, the present disclosure can be readily expanded to hypochlorous- acid-based sanitization and deodorization applications that require shorter killing or treatment time and safe operation, which would cover household, industrial, institutional, health care and other areas.

[0121] The present disclosure envisions use of devices and systems for producing take- home or retail type hypochlorous acid based oral irrigation products for dental applications or for sanitization. The inventive subject matter can be used for a commercial on-site, oral hypochlorous acid irrigation product for prevention or treatment of periodontal disease and peri-implant diseases, halitosis in oral healthcare clinic, or sanitization and deodorization at the dental office, hospital, nursing house, sports venue, food-processing plant, and other facilities.

[0122] All definitions, as defined and used herein, should be understood to control over dictionary definitions, definitions in documents incorporated by reference, and / or ordinary meanings of the defined terms.

[0123] The indefinite articles "a" and "an," as used herein in the specification and in the claims, unless clearly indicated to the contrary, should be understood to mean "at least one." Inaddition, singular references do not exclude a plurality. Thus, references to "a", "an", "first", "second" etc. do not preclude a plurality.

[0124] Reference signs in the claims are provided merely as a clarifying example shall not be construed as limiting the scope of the claims in any way.

[0125] The phrase "and / or," as used herein in the specification and in the claims, should be understood to mean "either or both" of the elements so conjoined, i.e., elements that are conjunctively present in some cases and disjunctively present in other cases. Multiple elements listed with "and / or" should be construed in the same fashion, i.e., "one or more" of the elements so conjoined. Other elements may optionally be present other than the elements specifically identified by the "and / or" clause, whether related or unrelated to those elements specifically identified.

[0126] As used herein in the specification and in the claims, "or" should be understood to have the same meaning as "and / or" as defined above. For example, when separating items in a list, "or" or "and / or" shall be interpreted as being inclusive, i.e., the inclusion of at least one, but also including more than one, of a number or list of elements, and, optionally, additional unlisted items. Only terms clearly indicated to the contrary, such as "only one of" or "exactly one of," or, when used in the claims, "consisting of," will refer to the inclusion of exactly one element of a number or list of elements. In general, the term "or" as used herein shall only be interpreted as indicating exclusive alternatives (i.e. "one or the other but not both") when preceded by terms of exclusivity, such as "either," "one of," "only one of," or "exactly one of."

[0127] It should also be understood that, unless clearly indicated to the contrary, in any methods claimed herein that include more than one step or act, the order of the steps or acts of the method is not necessarily limited to the order in which the steps or acts of the method are recited.

[0128] In the claims, as well as in the specification above, all transitional phrases such as "comprising," "including," "carrying," "having," "containing," "involving," "holding," "composed of," and the like are to be understood to be open-ended, i.e., to mean including but not limited to.

[0129] While several inventive embodiments have been described and illustrated herein, those of ordinary skill in the art will readily envision a variety of other means and / or structures for performing the function and / or obtaining the results and / or one or more of the advantages described herein, and each of such variations and / or modifications is deemed to be within the scope of the inventive embodiments described herein. More generally, those skilled in the art will readily appreciate that all parameters, dimensions, materials, and configurations described herein are meant to be exemplary and that the actual parameters, dimensions, materials, and / or configurations will depend upon the specific application or applications for which the inventive teachings is / are used. Those skilled in the art will recognize, or be able to ascertain using no more than routine experimentation, many equivalents to the specific inventive embodiments described herein. It is, therefore, to be understood that the foregoing embodiments are presented by way of example only and that, within the scope of the appended claims and equivalents thereto, inventive embodiments may be practiced otherwise than as specifically described and claimed. Inventive embodiments of the present disclosure are directed to each individual feature, system, article, material, kit, and / or method described herein. In addition, any combination of two or more such features, systems, articles, materials, kits, and / or methods, if such features, systems, articles, materials, kits, and / or methods are not mutually inconsistent, is included within the inventive scope of the present disclosure.

Claims

CLAIMSWhat is claimed is:

1. A disinfecting system (10), comprising: a liquid irrigator (12) including a pump mechanism (28) and an applicator (30); an hypochlorous acid generator assembly (14) functionally coupled to the liquid irrigator, the hypochlorous acid generator assembly is adapted to produce a hypochlorous acid solution and holds the hypochlorous acid solution within a targeted pH range in a reservoir (22); wherein the pump mechanism (28) of the liquid irrigator (12) withdraws fluid from the reservoir (22) to the applicator (30) to apply an effective amount of hypochlorous acid solution to a surface to be treated; and wherein the hypochlorous acid solution is prepared on-site and just prior to application.

2. The system of claim 1, wherein the hypochlorous acid generator assembly (14) comprises an electrolyte (24) , a pH adjusting agent (44), an electrolysis unit (16) to produce chlorine gas, and a conversion unit (18) wherein hypochlorous acid is produced via hydration of the produced chlorine gas.

3. The system of claim 2, wherein the electrolysis unit includes a polymer electrolyte membrane (202) and the electrolyte is hydrochloric acid.

4. The system of claim 2, wherein the electrolysis unit includes a cation selective membrane (302) and the electrolyte is selected from sodium chloride, potassium chloride, and / or other nontoxic chloride salt.

5. The system of claim 1, wherein the targeted pH range is a pH range between about 5.5 and about 6.0.

6. The system of claim 1, wherein the hypochlorous acid generator assembly comprises a reservoir for containing the hypochlorous acid solution produced by a wet-end reaction of mixing predetermined amounts of a hypochlorite containing component and an acid containing component.

7. The system of claim 6, wherein the hypochlorite containing component is selected from sodium hypochlorite and calcium hypochlorite.

8. The system of claim 6, wherein the acid containing component is selected from hydrochloric acid, phosphoric acid, sulfuric acid, carbonic acid, acetic acid, citric acid, or other compatible acid.

9. The system of claim 6, wherein the hypochlorite containing component includes a concentration of sodium hypochlorite within a range of about 0.1 % to about 5.0 % (wt. / wt.) and a concentration of hydrochloric acid within a range of about 0.1 % to about 5.0 % (wt. / wt. %).

10. An oral irrigation system (10) comprising: an oral irrigator (12); an hypochlorous acid generator assembly (14) functionally coupled to the oral irrigator, the hypochlorous acid generator assembly is adapted to produce a hypochlorous acid solution and holds the hypochlorous acid solution within a targeted pH range in a reservoir (22); wherein the oral irrigator (12) applies an effective amount of the hypochlorous acid solution to an oral surface to be treated; and wherein the hypochlorous acid solution is prepared on-site and just prior to application.

11. The system of claim 10, wherein the hypochlorous acid solution has a concentration of hypochlorous acid in a range of about 10 ppm to about 200 ppm.

12. The system of claim 10, wherein the targeted pH range is a pH range between about 5.5 and about 6.0.

13. The system of claim 10, wherein the hypochlorous acid generator comprises an electrolyte, a pH adjusting agent, an electrolysis unit to produce a chlorine gas, and a conversion unit wherein hypochlorous acid is produced via hydration of the produced chlorine gas.

14. The system of claim 13, wherein the electrolysis unit includes a polymer electrolyte membrane and the electrolyte is hydrochloric acid.

15. The system of claim 13, wherein the electrolysis unit includes a cation selective membrane and the electrolyte is selected from sodium chloride, potassium chloride, and / or other non-toxic chloride salt.

16. The system of claim 10, wherein the hypochlorous acid generator assembly comprises a reservoir for containing the hypochlorous acid solution produced by a wet-end reaction of mixing predetermined amounts of a hypochlorite containing component and an acid containing component.

17. The system of claim 10, wherein functional ingredients are added to the hypochlorous acid solution, the functional ingredients are compatible with hypochlorous acid for at least about 30 minutes at a temperature of less than about 40 degrees Celsius.

18. A method (400) for disinfecting a surface, the method comprising: providing (410) a liquid irrigator including a pump mechanism and an applicator; providing (420) an hypochlorous acid generator assembly functionally coupled to the liquid irrigator, the hypochlorous acid generator assembly is adapted to produce a hypochlorous acid solution and holds the hypochlorous acid solution within a targeted pH range in a reservoir; activating (430) the liquid irrigator and hypochlorous acid generator assembly;producing (440) the hypochlorous acid solution on-site and just prior to application; activating (450) the pump mechanism to withdraw fluid from the reservoir to the applicator; and applying (460) an effective amount of the hypochlorous acid solution to the surface to be treated.

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