JPH0524959B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to the sanitization and disinfection of flush toilets. More particularly, the present invention relates to automatic toilet bowl cleaners. BACKGROUND OF THE INVENTION A number of different compositions and methods for disinfecting flush toilets have been proposed. These can be dispensed from single chamber dispensers such as those described in U.S. Pat. No. 4,318,891 or from two chamber dispensers such as those described in U.S. Pat. There are various hypochlorous acid and chloramine compounds that can be used. Although disinfectant compositions can be used as granules, they are more commonly used as tablets. In order to work effectively in automatic toilet bowl cleaners, disinfectant tablets must possess a number of properties. The tablets have a useful life of close to 300 washes, with concentrations ranging from about 2 ppm to about 30 ppm per wash.
Preferably, a disinfectant concentration of about 5 ppm to about 20 ppm should be produced. The tablet must not produce objectionable chloramines or other objectionable odors. The tablet must retain its integrity throughout the useful life of the toilet bowl cleaner, yet block the various holes and passageways in the dispenser through which water circulates as the toilet cistern fills and drains. It must not shatter or disintegrate. Disinfectant tablets must not cause corrosion of metal parts of the toilet bowl or other adverse effects on other parts of the fitting. Tablets should not significantly contribute to the formation of scale or other insolubles or contain insoluble ingredients. Additionally, the tablets must not contribute toxic substances to the sewage system, water supply, or environment. The most commonly used disinfectant tablet materials are calcium hypochlorite and trichloroisocyanuric acid. Each of these materials has major drawbacks. Calcium hypochlorite contains insoluble components that can clog the pores of the dispenser and also contributes to water hardness and scale formation by adding calcium ions to the water. Trichloroisocyanuric acid is a strong acid and can generate an unpleasant chloramine odor under some circumstances. A disinfectant tablet that produces adequate concentrations of disinfectant with the necessary longevity and tablet integrity, but without the negative properties discussed above, would be an advance in the art. SUMMARY OF THE INVENTION According to the present invention, an alkali metal salt of cycloisocyanuric acid, preferably sodium dichloroisocyanurate dihydrate and a chloride salt selected from the group consisting of calcium chloride and barium chloride, preferably calcium chloride dihydrate and chloride A flush toilet comprising barium dihydrate in a molar ratio of alkali metal dichloroisocyanurate to chloride salt not greater than 4:1, preferably not greater than 3:1, and most preferably substantially stoichiometric. Tablets suitable for disinfection are provided. The tablets preferably contain at least about alkali metal dichloroisocyanurate.
40%, preferably at least about 50%, most preferably at least about 60%. It is also preferred that the tablets contain a mold release agent such as boric acid or monoglyceryl stearate. According to the present invention,
Further, the tablet is characterized in that the water supplied to flush the toilet bowl, preferably the water supplied to flush the toilet bowl, comes into contact with water contained in a water tank that is part of the toilet bowl. Instructions for disinfecting flush toilets will also be provided. DESCRIPTION OF THE INVENTION The use of alkali metal salts of dichloroisocyanuric acid in tabletted toilet disinfectants has the major drawback that the solubility of these alkali metal salts in water is sufficiently great that the tablets do not have sufficient longevity. have The tablets of the present invention contain alkali metal salts of dichloroisocyanuric acid by providing barium and calcium ions that react with dichloroisocyanuric acid to form barium di(dichloroisocyanurate) or calcium di(dichloroisocyanurate). Decrease solubility. These divalent metal salts have lower solubility than alkali metal salts, and tablets exhibit this lower solubility. In short, the tablets were made as if they were made at least in part from barium di(dichloroisocyanurate) or calcium di(dichloroisocyanurate) instead of the more common and lower cost alkali metal salts of dichloroisocyanurate. behave. In theory, this same approach is suitable with various divalent metal salts. however,
In order to be effective in dispensers commonly used with toilet bowl cleaners, the formulation must be tablettable. In the dispenser,
Typically, a container for disinfectant tablets is included that has an opening or passageway through which water flows during the flush cycle.
In this way, the tablets dissolve and release the disinfectant by being partially or fully immersed in water. This solution is dispensed into the toilet bowl during flushing. This type of dispenser is covered by U.S. Patent No.
No. 3618143 and No. 4208747. In this type of dispenser and other dispensing systems, water must flow around the toilet bowl to obtain adequate elution of the disinfectant, yet maintain its integrity so that the openings and passageways are not clogged. There is. The formulations of the present invention form tablets that do not disintegrate in water like many other formulations containing other divalent metal compounds. This tablet consistency is central to the practice of this invention. The tablets of the invention are particularly suitable for use in dispensers of the type described above, provided that the flushing water washes over the tablets suspended below the rim of the toilet bowl.
It can be used with other disinfection systems either where tablet integrity is necessary or desirable, such as in "under the rim" type toilet bowl cleaners. The alkali metal salt of dichloroisocyanuric acid that can be used with the present invention can be either potassium or sodium, with sodium being preferred. It is also preferable that the alkali metal salt of dichloroisocyanuric acid is sufficiently hydrated. Sodium dichloroisocyanurate dihydrate is the most preferred type. The tablets are preferably at least about 40%, more preferably at least about 50%, most preferably at least about 60% by weight of the alkali metal salt of dichloroisocyanuric acid. For the tablets of the present invention to function, sufficient barium chloride or calcium chloride must be present to convert a substantial portion of the alkali metal salt to the calcium or barium salt. The molar ratio of dichloroisocyanuric acid to barium or calcium is not greater than 4:1, preferably not greater than 3:1, and most preferably 2:1.
Good results are obtained when the amount is not greater than (stoichiometric). Also, an excess of barium chloride or calcium chloride can be used. In addition to the above-mentioned ingredients, the tablet can also contain further ingredients. Trichloroisocyanuric acid can be added to increase the amount of available chlorine in the formulation. "Effective chlorine"
is a commonly used term meaning the amount of active chlorine by weight of the composition compared to the amount of active chlorine by weight in the chlorine gas expressed as a %.
If the amount of trichloroisocyanuric acid in the composition is too high, an undesirable chloramine odor may occur. Tablets may contain tablet aids such as lubricants, mold release agents, binders. The most commonly used mold release agents are boric acid and monoglyceryl stearate. Preferably, the formulation contains about 2% mold release agent. The formulation may also contain fillers such as sodium chloride. The filler may serve to reduce solubility, aid tableting, or serve other functions. It is preferred that all components of the formulation are sufficiently hydrated so that hydration, which can be detrimental to tablet integrity, does not occur after tabletting. The tablets of the present invention can be used alone to provide disinfection of the toilet bowl or preferably in combination with other tablets providing detergents or surfactants, fragrances, dyes, etc. to provide a more complete toilet bowl cleaning. The following examples illustrate the invention and are not intended to limit it in any way. In the examples and discussion above, all parts and percentages are by weight unless otherwise specified. Examples 1 to 8 Tablets with a diameter of 1.75 inches (3.8 cm) were
9100psi or 9800psi (62700kPa or more
67500kPa) on a press. This tablet contained 33g of the indicated composition. Sodium dichloroisocyanurate dihydrate (NaCl ₂ CYA·2H ₂ O) was used as the alkali metal dichloroisocyanurate. In addition, each tablet contained 1% H ₃ BO ₃ and 0.5% monoglyceryl stearate, which acts as a mold release agent. tablets,
It was placed in a dispenser similar to that described in US Pat. No. 4,208,747, and the dispenser was placed in a container of water. The dispenser was periodically raised and drained from the water to simulate flushing a toilet bowl. The amount of active chlorine dispensed is determined amperometrically and calculated as ppm released into the toilet bowl.
The concentration of chlorine was evaluated and reported as “chlorine ppm”.
In addition, "lifespan" was also evaluated in days. These data were not available because many tablets swelled and disintegrated. The results are reported in Table 1.

[Table] As can be seen from the data in Table 1, mixtures of alkali metal dichloroisocyanurates and divalent metal compounds are very difficult to tablet. The only compounds for which tablets have been successfully manufactured are barium chloride and calcium chloride. Examples 9 to 12 Tablets of similar diameter to those of Examples 1 to 8 were similarly prepared, except that 50 g of the composition was used. Tablets were made using barium and calcium chloride and sodium dichloroisocyanurate in the percentages indicated along with 1% H ₃ BO ₃ and 1% monoglyceryl stearate. The tablets were placed in a dispenser similar to that used in Examples 1 to 8, and the dispenser was placed in a standard flush toilet water tank suitable for automatic flushing approximately every hour. Samples of water are taken periodically and then "chlorine ppm" as in Examples 1 to 8.
The reported chlorine concentration was analyzed in ppm and the lifespan of the tablet was determined assuming approximately 10 washes each day. The results are shown in Table 2, along with the molar ratio of Na ₂ CYA.2H ₂ O to barium or calcium.

Table: Each tablet maintained its integrity throughout the test.
The lifespan of tablets, especially those using calcium chloride, was less than the 30 days required for most commercial toilet bowl cleaners. This means that
This could be corrected by increasing the tablet size, adding fillers to reduce tablet solubility, or both. By making these fairly minor adjustments, toilet bowl formulations could be produced that take advantage of the good tableting properties of these formulations.

Claims (1)

[Scope of Claims] 1 An alkali metal salt of dichloroisocyanuric acid and a chloride salt selected from calcium chloride and barium chloride, and the molar ratio of the alkali metal to chloride salt of dichloroisocyanuric acid is 4:1.
Tablets suitable for disinfecting flush toilets, characterized in that they are not larger. 2. The tablet of claim 1, wherein the alkali metal salt of dichloroisocyanuric acid is sodium dichloroisocyanurate dihydrate. 3. The tablet of claim 2, wherein the chloride salt is calcium chloride dihydrate. 4. The tablet of claim 2, wherein the chloride salt is barium chloride dihydrate. 5. The tablet according to claim 1, further comprising a mold release agent. 6. The tablet of claim 1, wherein the chloride salt is calcium chloride. 7. The tablet of claim 1, wherein the chloride salt is barium chloride. 8. The tablet of claim 1, wherein the molar ratio of alkali metal dichloroisocyanurate to chloride salt is not greater than 3:1. 9. The tablet of claim 1, wherein the molar ratio of alkali metal dichloroisocyanurate to chloride salt is substantially stoichiometric. 10 The alkali metal salt of dichloroisocyanurate is sodium dichloroisocyanurate dihydrate in an amount of at least about 40% by weight, and the chloride salt is barium chloride dihydrate or calcium chloride dihydrate, and one or more A tablet according to claim 1, comprising a mold release agent as defined above, wherein the molar ratio of sodium dichloroisocyanurate to chloride salt is not greater than 3:1. 11. The tablet of claim 10, wherein the molar ratio of sodium dichloroisocyanurate to chloride salt is substantially stoichiometric.