CN121002161A - Unit dose tablets - Google Patents

Abstract

This invention pertains to the field of cleaning compositions. The invention relates to unit-dose tablets that provide a liquid cleaning composition when dissolved in water. There is a need for an improved tablet containing a significantly high amount of detergency active ingredient, which is hard but still dissolves rapidly upon contact with water. The invention provides a tablet comprising 5 to 80% by weight of a surfactant selected from anionic surfactants, nonionic surfactants, and combinations thereof; a co-solvent comprising an alkyl aryl sulfonate having a C1 to C5 alkyl chain; and a selected disintegrant, wherein the surfactant comprises at least an anionic surfactant that is an alkyl cocoyl taurate. The tablet rapidly disintegrates upon contact with water, thereby providing a liquid cleaning composition. The invention also provides methods for obtaining hard surface cleaners and methods for cleaning surfaces.

Description

Unit dose tablet

Technical Field

The present invention is in the field of cleaning compositions. In particular, the present invention relates to unit dose tablets which provide a liquid cleaning composition when dissolved in water.

Background

Consumers spend a great deal of time and effort cleaning their homes. Depending on the substrate to be cleaned, they preferably use different cleaning products. Typically, such products differ in their ingredients, such as detergents, builders, fragrances and the like. Furthermore, certain products are available in different forms, such as powders, liquids, tablets and capsules. In general, consumers prefer products in tablet form because of the compact size of the tablets and the controlled dosage provided.

Typically, cleaning products in tablet form contain concentrated cleaning or detersive actives. The consumer dissolves the tablet in water to form a cleaning composition, thereby using it. Conventionally, tablets are formed by compacting a homogenized powder containing the desired ingredients. On the one hand, high compression forces result in hard tablets that do not dissolve rapidly. On the other hand, lower compression forces result in loosely packed ingredients, which contribute to faster dissolution, however, they do not have the required strength. In this case, it is desirable that the tablet be hard enough to resist breakage during transport/storage, but still dissolve rapidly upon contact with water.

Furthermore, it is implicitly desirable that the tablet provides improved cleaning efficacy. One way to achieve this is by increasing the amount of detergent active in the tablet. However, this may result in densely packed hard tablets with a relatively slow dissolution rate. Furthermore, increasing the detergent active may be compensated by reducing the amount of disintegrant, thereby further affecting dissolution.

In this regard, WO 08/8040151 describes solid synthetic detergents comprising anionic surfactants, disintegrants and builders, wherein at least one surfactant surrounding the particles comprising the detergent ingredients acts as a disintegrating component, and the disintegrants also include polyvinylpyrrolidone, succinic acid or citric acid and sodium bicarbonate.

US 2002082187 describes effervescent compounds comprising a solvent and an effervescent system. The solvent may include glycol ethers such as, but not limited to, 2-butoxyethanol. The effervescent system used in the effervescent compound may be, for example, but is not limited to, sodium foaming perborate or a mixture of sodium bicarbonate, sodium carbonate and acid.

US 2005/0148488 (Henkel, 2005) describes a multi-phase detergent tablet having at least one active phase containing one or more wash or cleaning substances, a solid matrix in solidified melt form encapsulating the substances, wherein the matrix material is selected from the group consisting of sugar, sugar acid, sugar alcohol and any mixtures thereof. The solid matrix has a solubility of greater than 100 gm/L at 20 ℃ and it is at least 10% of the total weight of the active phase.

WO 00/27986 (Henkel, 2000) describes detergent tablets which are characterized by a combination of high hardness and short disintegration time. Such tablets may be prepared by adding fine particulate sugar wherein at least 50% by weight of the sugar particles have a size of less than 400 microns.

CA 2324070A1 (Henke, 2001) discloses compositions containing 60 to 95 wt.% of an anionic surfactant, 5 to 40 wt.% of a hydrotrope and 0 to 35 wt.% of a carrier material, which provides detergent tablets with increased impact and friction properties.

WO 2022/258413A1 (Unilever, 2022) discloses a unit dose detergent tablet comprising at least 10wt% of a surfactant and a dissolution aid selected from the group consisting of hydrated monosaccharides, hydrated disaccharides, hydrated oligosaccharides and combinations thereof, wherein the weight ratio of surfactant to dissolution aid is at least 1:1.5.

Despite the prior art, there remains a need for an improved tablet containing significantly high amounts of detergent active that is hard but yet dissolves rapidly upon contact with water.

While this was studied, the present inventors have surprisingly found that unit dose tablets comprising an alkyl cocoyl taurate-based anionic surfactant and a selected hydrotrope disintegrate rapidly in water in the presence of a selected disintegrant, thereby providing a liquid cleaning composition.

Disclosure of Invention

In a first aspect, the present invention provides a unit dose tablet comprising:

a) 5 to 80 wt% of a surfactant selected from the group consisting of anionic surfactants, nonionic surfactants, and combinations thereof;

b) A hydrotrope comprising an alkylaryl sulfonate having a C1 to C5 alkyl chain, and

C) A disintegrant comprising a water soluble disintegrant having a solubility in distilled water of at least 100 g/L at 25 ℃,

Wherein the surfactant comprises an anionic surfactant that is at least an alkyl cocoyl taurate.

In another aspect, the present invention provides a hard surface cleaner obtained by dissolving a tablet according to the first aspect in water, wherein the weight ratio of tablet to water is in the range of 1:5 to 1:100.

In a further aspect, the present invention provides a method for cleaning a surface comprising the steps of:

a) Providing water in a container;

b) Adding and dissolving a tablet according to the first aspect in water, wherein the weight ratio of tablet to water is in the range of 1:50 to 1:1000, thereby providing a liquid cleaning composition, and

C) The cleaning composition is applied to a surface and cleaned.

These and other aspects, features and advantages will become apparent to those of ordinary skill in the art upon reading the following detailed description. For the avoidance of doubt, any feature of one aspect of the present invention may be used in any other aspect of the present invention. The word "comprising" is intended to mean "including", but not necessarily "consisting of. In other words, the listed steps or options need not be exhaustive. It should be noted that the examples given in the following description are intended to clarify the invention and are not intended to limit the invention to those examples per se. Similarly, all percentages are weight/weight percentages unless otherwise indicated. Except in the operating and comparative examples, or where otherwise explicitly indicated, all numbers in this description indicating amounts of material or conditions of reaction, physical properties of materials and/or use are to be understood as modified by the word "about". The numerical range expressed in the format "x to y" should be understood to include x and y. When multiple preferred ranges are described in the format of "x to y" for a particular feature, it is to be understood that all ranges combining the different endpoints are also contemplated.

Detailed Description

As used herein, "unit dose" means the amount of a composition suitable for one-time use.

As used herein, "effervescent system" refers to a compound or combination of two or more compounds that produces effervescence upon contact with water.

As used herein, "disintegrant" refers to an ingredient present in a tablet to accelerate dissolution of the tablet in water. Upon contact with water, these ingredients break or disintegrate the tablet into smaller pieces, thereby accelerating dissolution.

According to the present invention there is provided a tablet comprising a surfactant, a hydrotrope comprising an alkylaryl sulfonate having a C1-C5 alkyl chain and a disintegrant. The surfactant is selected from the group consisting of anionic surfactants, nonionic surfactants, and combinations thereof, wherein the surfactant comprises at least an anionic surfactant that is an alkyl cocoyl taurate salt.

Surface active agent

The tablet according to the invention comprises a surfactant. The tablet contains 5-80 wt% of surfactant. Preferably, the amount of surfactant is in the range of 7-75 wt%, more preferably 10-70 wt%, most preferably 12-65 wt% of the tablet.

The surfactant in the tablet is selected from anionic surfactants, nonionic surfactants, and combinations thereof.

Anionic surfactants

The tablet comprises at least an anionic surfactant that is an alkyl cocoyl taurate salt. It was observed that the alkyl cocoyl taurates contributed to faster dissolution in addition to the hydrotrope. The alkyl cocoyl taurate may constitute 100% by weight of the total amount of anionic surfactant present in the tablet. The alkyl cocoyl taurate may comprise 50 to 100% by weight of the total surfactant. More preferably, the alkyl cocoyl taurate in the tablet is in the range of 10 to 90 wt%, even more preferably 20 to 80 wt%, most preferably 30 to 75 wt% of the total amount of anionic surfactant. The alkyl cocoyl taurate may comprise 50 to 100% by weight of the total surfactant.

Preferably, the tablet comprises another anionic surfactant than alkyl cocoyl taurates.

Anionic surfactants suitable for use in the present invention include salts of organic sulfuric and sulfonic acids having an alkyl group containing from about 8 to about 22 carbon atoms, the term "alkyl" being used to include the alkyl portion of higher acyl groups. Examples of such materials include alkyl sulfates, alkyl ether sulfates, alkylaryl sulfonates, alpha olefin sulfonates, and mixtures thereof. The alkyl group preferably contains 10 to 18 carbon atoms and may be unsaturated. The alkyl ether sulphates may contain from 1 to 10 ethylene oxide or propylene oxide units per molecule, preferably from 1 to 3 ethylene oxide units per molecule.

Suitable anionic surfactants include alkylbenzene sulfonates. Preferably, in embodiments suitable for dishwashing, the Linear Alkylbenzene Sulfonate (LAS) is comprised of an alkyl chain length of 10 to 18 carbon atoms. Commercially available LAS is a mixture of closely related isomers and homologs of alkyl chains, each containing an aromatic ring sulfonated in the "para" position and attached to the linear alkyl chain at any position other than the terminal carbon. The straight alkyl chain typically has a chain length of 11 to 15 carbon atoms, with the primary material having a chain length of about C12. Each alkyl chain homolog consists of a mixture of all possible sulfo-phenyl isomers except the 1-phenyl isomer. LAS is typically formulated into the composition in the form of an acid (i.e., HLAS) and then at least partially neutralized in situ. The counter ion of the anionic surfactant is typically an alkali metal such as sodium or potassium, or an ammonia counter ion such as Monoethanolamine (MEA), diethanolamine (DEA) or Triethanolamine (TEA), monoisopropanolamine (MIPA), monoisopropylamine. Mixtures of such counterions can also be used. Sodium and potassium are preferred.

Preferably, suitable anionic surfactants include alkyl sulfate surfactants (PAS), such as non-ethoxylated primary and secondary alkyl sulfates having alkyl chain lengths of 10-18.

Tablets may contain alkyl ether sulphates having a linear or branched alkyl group containing from 10 to 18, more preferably from 12 to 14 carbon atoms and containing an average of from 1 to 3 Ethylene Oxide (EO) units per molecule. A preferred example is Sodium Lauryl Ether Sulphate (SLES) in which the main C12 lauryl alkyl group is ethoxylated with an average of 3EO units per molecule. The alkyl ether sulfates may be used alone or in combination with any other anionic surfactant. The anionic surfactant in liquid form may be adsorbed on the inorganic salt and may be obtained as a free flowing powder.

The anionic surfactant may be selected from the group consisting of alkylbenzene sulfonates, alkyl ether sulfates, alkyl cocoyl taurates, and combinations thereof. Preferably, the anionic surfactant comprises an alkyl cocoyl taurate.

Preferably, the anionic surfactant is a combination of an alkyl cocoyl taurate salt with at least one selected from the group consisting of alkyl sulphates, alkyl ether sulphates and linear alkyl benzene sulphonates. The most preferred alkyl cocoyl taurates are methyl cocoyl taurates and/or sodium salts thereof.

The anionic surfactant may constitute up to 100% by weight of the total amount of surfactant present in the tablet. More preferably, the anionic surfactant in the tablet is in the range of 10-90 wt%, even more preferably 20-80 wt%, most preferably 30-70 wt% of the total amount of surfactant.

Preferably, the amount of anionic surfactant in the tablet is in the range of 5-75% by weight. More preferably, the amount of anionic surfactant in the tablet is in the range of 7.5 to 75 wt%, even more preferably 10 to 75 wt%, most preferably 15 to 75 wt%.

Nonionic surfactant

Tablets according to the invention may contain nonionic surfactants.

Suitable nonionic surfactants include water-soluble aliphatic ethoxylated nonionic surfactants, including primary aliphatic alcohol ethoxylates and secondary aliphatic alcohol ethoxylates. This includes condensation products of higher alcohols (e.g., straight or branched chain configuration alkanols containing from about 8 to 16 carbon atoms) with from about 4 to 20 moles of ethylene oxide, for example, lauryl or myristyl alcohol with about 10 moles of Ethylene Oxide (EO), tridecyl alcohol with about 6 to 15 moles of EO, myristyl alcohol with about 10 moles of EO per mole of myristyl alcohol, condensation products of EO with coconut fatty alcohol fractions containing mixtures of fatty alcohols having alkyl chain lengths of from 10 to about 14 carbon atoms, and wherein the condensate contains about 6 moles of EO per mole of total alcohol or about 9 moles of EO per mole of alcohol and tallow alcohol ethoxylates containing 6EO to 11EO per mole of alcohol.

Examples of the aforementioned nonionic surfactants include, but are not limited to, neodol (trademark from Shell), which is a higher primary aliphatic alcohol having about 9 to 15 carbon atoms, such as C9-C11 alkanols condensed with 4 to 10 moles of ethylene oxide (Neodol 91-8 or Neodol 91-5), C12-C13 alkanols condensed with 6.5 moles of ethylene oxide (Neodol 23-6.5), C12-C15 alkanols condensed with 12 moles of ethylene oxide (Neodol 25-12), C14-C15 alkanols condensed with 13 moles of ethylene oxide (Neodol 45-13), and the like. Such ethoxamers have an HLB (hydrophobic lipophilic balance) value of about 8-15 and give good O/W emulsification, whereas ethoxamers with HLB values below 7 contain less than 4 ethylene oxide groups and tend to be poor emulsifiers and poor detergents.

Another group of suitable nonionic surfactants are Alkyl Polyglycosides (APGs), which are sugar derivatives of fatty alcohols. Examples of such surfactants are decyl glucoside, lauryl glucoside, myristyl glucoside.

Preferably, the amount of nonionic surfactant in the tablet is in the range of 5-75% by weight. More preferably, the amount of nonionic surfactant in the tablet is in the range of 7.5 to 75 wt%, even more preferably 10 to 75 wt%, most preferably 15 to 75 wt%.

The tablet may comprise a combination of anionic and nonionic surfactants. Preferably, the combination may contain anionic surfactant and nonionic surfactant in a weight ratio of 5:1 to 5:1.

In addition to anionic and/or nonionic surfactants, the tablet may also contain cationic surfactants.

Suitable cationic surfactants are quaternary ammonium salts. According to the invention, the quaternary ammonium salts are characterized by the general formula R1R2R3R4N ⁺X^-, wherein R1 is C12-C18 alkyl, R2, R3 and R4 are each independently C1-C3 alkyl and X is an inorganic anion. R1 is preferably a C14-C16 linear alkyl group, more preferably C16. R2, R3 and R4 are preferably methyl. The inorganic anion (X-) is preferably selected from the group consisting of halide, sulfate, bisulfate or hydroxide.

For the purposes of the present invention, quaternary ammonium hydroxides are considered quaternary ammonium salts. More preferably, the anion is a halide or sulfate, most preferably chloride or sulfate. Cetyl-trimethylammonium chloride is a specific example of a suitable compound and is commercially available in large quantities.

Another type of quaternary ammonium cationic surfactant is the benzalkonium halides (benzalkonium halide) class, also known as alkyl dimethylbenzyl ammonium halides. The most common type is benzalkonium chloride, also known as alkyl dimethyl benzyl amine chloride (or ADBAC).

In addition to anionic and/or nonionic surfactants, amphoteric surfactants may also be present in the tablet.

Suitable amphoteric surfactants include derivatives of aliphatic quaternary ammonium, sulfonium and phosphonium compounds having an aliphatic group of 8 to 18 carbon atoms and an aliphatic group substituted with an anionic water-solubilizing group, for example 3- (N-dimethyl-N-hexadecylammonium) propane-1-sulfonate betaine, 3- (dodecylmethylsulfonium) propane-1-sulfonate betaine and 3- (hexadecylmethyl phosphonium) ethane sulfonate betaine.

Examples of amphoteric surfactants suitable for use in the present invention include cocamidopropyl betaine (CAPB), cocamidopropyl amine oxide (CAPAO), cocodiethanolamide (CDEA), and Cocomonoethanolamide (CMEA).

Hydrotrope

The tablet comprises a hydrotrope comprising an alkylaryl sulfonate having a C1 to C5 alkyl chain. It was observed that the hydrotrope accelerated the disintegration of the tablet in the presence of the disintegrant and the selected surfactant.

Hydrotropes are a class of low molecular weight compounds having hydrophilic and hydrophobic portions similar to surfactants. However, the hydrophobic moiety is much smaller than the surfactant. Thus, they may not lead to spontaneous self-aggregation or micelle solubilization. It was also observed that the hydrotrope did not have Critical Micelle Concentration (CMC) or Critical Vesicle Concentration (CVC) as surfactant. It is possible that the hydrotrope aggregates during the gradual self-aggregation process, thereby gradually increasing the aggregate size.

The tablet preferably contains 0.1 to 10% by weight of a hydrotrope. More preferably, the tablet comprises 0.2 to 9 wt%, even more preferably 0.3 to 8 wt%, most preferably 0.3 to 7 wt% of a hydrotrope.

The hydrotrope comprises an alkylaryl sulfonate having a C1 to C5 alkyl chain. The alkylaryl sulfonate may be selected from the group consisting of sodium xylene sulfonate, sodium toluene sulfonate, sodium cumene sulfonate, potassium xylene sulfonate, potassium toluene sulfonate, potassium cumene sulfonate, and combinations thereof. The most preferred alkylaryl sulfonate co-solvent is sodium cumene sulfonate and/or sodium xylene sulfonate.

Disintegrating agent

The tablet comprises a disintegrant. Disintegrants are used in tablet environments to facilitate the breaking up or disintegration of the tablet into smaller pieces, thereby aiding in the dissolution of the detergent active in water. Surprisingly, it was observed in the present invention that the selected hydrotrope aids the disintegration process in the presence of the disintegrant and the selected surfactant.

Preferably, the tablet comprises 10-90% by weight of disintegrant. More preferably, the tablet comprises 15 to 85 wt%, even more preferably 20 to 80 wt%, most preferably 25 to 75 wt% of the disintegrant.

The disintegrant comprises a water soluble disintegrant having a solubility in distilled water of 100 g/L at 25 ℃. More preferably, the solubility of the water-soluble disintegrant in distilled water at 25 ℃ is greater than 200 g/L, even more preferably greater than 300 g/L, most preferably greater than 400 g/L. Tablets containing such disintegrants leave no residue in water when added to water, thereby providing a clear liquid cleaning composition upon dilution.

Preferably, the water-soluble disintegrant is selected from the group consisting of hydrated monosaccharides, hydrated disaccharides and hydrated oligosaccharides. The most preferred water-soluble disintegrant is glucose monohydrate.

Preferably, the water-soluble disintegrant is present in at least 50wt%, more preferably at least 70wt%, even more preferably at least 80wt%, most preferably at least 90 wt% of the total amount of disintegrant. The tablet may comprise a water-soluble disintegrant in an amount of up to 100% by weight of the total disintegrant. Preferably, the water-soluble disintegrant is 50-100% by weight of the total amount of the disintegrant.

Preferably, the amount of water-soluble disintegrant is in the range of 10-90% by weight of the tablet. More preferably, the amount of water-soluble disintegrant is in the range of 15 to 85 wt%, even more preferably 20 to 80 wt%, most preferably 25 to 75 wt% of the tablet.

The disintegrant may further comprise a water insoluble disintegrant. The water insoluble disintegrant may be selected from microcrystalline cellulose, sodium starch glycolate, polyvinylpyrrolidone, starch, calcium silicate, magnesium stearate, and combinations thereof. The polyvinylpyrrolidone comprises cross-linked polyvinylpyrrolidone.

The amount of water insoluble disintegrant, if present, may be in the range of1 to 60 wt%, more preferably 3 to 50 wt%, most preferably 5 to 40 wt% of the tablet.

Organic acid

The tablets according to the invention may contain an organic acid.

Preferably, the organic acid is selected from the group consisting of citric acid, tartaric acid, fumaric acid, malic acid, adipic acid, succinic acid, and combinations thereof. Preferably, the organic acid is citric acid.

Preferably, the tablet comprises 1 to 50 wt%, more preferably 3 to 45 wt%, most preferably 5 to 40 wt% of the organic acid.

Water-soluble inorganic salt

The tablet may comprise a water-soluble inorganic salt. Suitable inorganic salts include alkali metal salts of carbonic or bicarbonic acids or silicic acid, and combinations thereof.

Preferably, the carbonate or bicarbonate is selected from sodium carbonate, potassium carbonate, calcium carbonate, sodium bicarbonate, potassium bicarbonate, calcium carbonate, calcium bicarbonate, and magnesium carbonate, and mixtures thereof.

Preferably, the tablet comprises 1 to 50% by weight, more preferably 3 to 45% by weight, most preferably 5 to 40% by weight of the water-soluble inorganic salt.

The organic acid and the water-soluble insoluble material may be selected in combination for use as an effervescent source in a tablet. This combination further accelerates dissolution of the tablet in contact with water. Examples of such combinations include bicarbonate/carbonate salts with selected organic acids such as citric acid. Bicarbonate/carbonate and organic acid may be considered in a weight ratio of 10:1 to 1:10, more preferably 5:1 to 1:5, most preferably 3:1 to 1:3. Most preferably, the weight ratio of bicarbonate to organic acid or organic acid salt or inorganic acid salt is 1:1.

Chelating agent

The tablet may comprise a chelating agent. Examples include alkali metal salts, citrates, succinates, malonates, carboxymethyl succinates, carboxylates, polycarboxylates and polyacetylcarboxylates. Specific examples include sodium, potassium and lithium salts of oxydisuccinic acid, mellitic acid, benzene polycarboxylic acid and citric acid. Other examples are DEQUEST ^TM, an organic phosphonate type chelating agent sold by Monsanto, and an alkane hydroxy phosphonate.

The tablet may comprise from 0.1 to 6% by weight, more preferably from 0.2 to 5% by weight, even more preferably from 0.3 to 4% by weight, most preferably from 0.5 to 3% by weight of chelating agent. The preferred chelating agent is Dequest 2066 (diethylenetriamine penta (methylenephosphonic acid) or DTPMP heptasodium). Other suitable chelating agents are 1-hydroxyethylidene-1, 1-diphosphonic acid (HEDP) and methylglycine diacetic acid (MGDA), glutamic acid disodium salt (GLDA). The most preferred chelating agents are methylglycine diacetic acid (MGDA) and/or glutamic acid disodium salt (GLDA).

Stress at break

It is desirable that the tablet has a certain hardness to resist breakage during handling/transport.

One way to evaluate tablet hardness is radial fracture stress (DIAMETRICAL FRACTURE STRESS) (DFS). The tablet preferably has a ratio of radial fracture stress (DFS) of DFS _{Air-conditioner} /DFS _{Water and its preparation method} of at least 6, preferably at least 7, preferably at least 8, more preferably at least 9.

More preferably, the tablet has a ratio of the diameter stress at break (DFS) of DFS _{Air-conditioner} /DFS _{Water and its preparation method} in the range of 6-50, preferably 7-45.

The DFS _{Air-conditioner} /DFS _{Water and its preparation method} ratio can be measured using techniques known to those skilled in the art. DFS may be measured using a texture analyzer, such as CT3 Brookfield Texture Analyser. DFS _{Air-conditioner} /DFS _{Water and its preparation method} can be measured, for example, using TA instruments, model TA-XT2i and Texture Experte software (Texture Technologies corp., SCARSDALE, NY, USA/-Stable Micro Systems, surrey, england, UK). The instrument was calibrated with a 5 kg load cell and equipped with a stainless steel flat bottom cylindrical probe (Kobe probe) with a surface area of 1cm ². The method includes positioning a tablet on a planar surface of a probe. The probe is moved until a trigger force is detected at which point TA is set to remain at a predetermined nominal force for a given time (60 seconds). As the tablet begins to disintegrate, TA measures the penetration distance when the tablet is compressed while immersed in the medium (water). During the test, the constant temperature of the medium was maintained at 18 ℃ by means of a thermostatted double-walled bath and a heated bath/circulator (Haake, karlsruhe, germany).

Application of

Tablets may be formulated for hard surface cleaning. Hard surfaces herein include surfaces in the home such as kitchen utensils, floors, tiles, cutlery, kitchen platforms, desktops, and the like. The consumer may add the tablet to the bucket and dissolve it, thereby forming the cleaning composition. The compositions thereon are useful for cleaning surfaces such as tile and floors.

It is also possible for the consumer to add the tablet to a container or bottle filled with water and prepare a hard surface cleaner which can be stored and used at a later stage.

The tablets according to the invention may be provided together with a container having sufficient empty space. The consumer can fill the container with water, preferably to reach a preset mark, and add a tablet. The tablets dissolve in water, providing a cleaning product. Preferably, the container is transparent or translucent and the composition appears visually clear. Such an arrangement typically provides visual cues to the consumer. In the context of a composition, "visually clear" or "transparent" refers to a liquid having a turbidity value of less than 50 NTU (nephelometric turbidity units), more preferably less than 30 NTU, even more preferably 20 NTU, most preferably 10 NTU. The container may be equipped with a spray head or foam engine (foam engine) that aids in dispensing the cleaning composition as a spray or foam directly onto a surface.

According to the present invention there is provided a hard surface cleaner obtained by dissolving a tablet in water, wherein the weight ratio of tablet to water is in the range of 1:5 to 1:100. Preferably, the weight ratio of tablet to water is in the range of 1:7 to 1:80, more preferably 1:9 to 1:60, most preferably 1:10 to 1:50. The hard surface cleaner may be obtained by taking a container, filling the container with water, adding tablets and optionally shaking the container. The hard surface cleaner may be stored and used at a later stage. Preferably, the resulting insoluble-free tablets and hard surface cleaners are transparent. The term "insoluble-free" as used herein means that the tablet contains less than 5% by weight, more preferably less than 3% by weight, even more preferably less than 1% by weight, and most preferably less than 0.5% by weight of insoluble compounds. In some cases, the tablet does not contain an insoluble compound. The term "transparent" in this context means that the hard surface cleaner appears visually transparent or that the haze value of the liquid is less than 50 NTU (nephelometric turbidity units), more preferably less than 30 NTU, most preferably less than 10 NTU.

According to the present invention there is also provided a method for cleaning a surface comprising the steps of providing water in a container or tub, adding and dissolving a tablet into the water, wherein the weight ratio of tablet to water is in the range of 1:50 to 1:1000, thereby providing a liquid cleaning composition, and applying the cleaning composition to a surface and cleaning it. Preferably, the weight ratio of tablet to water is in the range of 1:75 to 1:800, more preferably 1:100 to 1:600, most preferably 1:150 to 1:500. Preferably, the cleaning composition is intended for immediate use and may not be stored for subsequent use. The consumer may use an applicator or implement, such as a cloth, wipe, brush, rag, to apply the cleaning composition and optionally rinse the surface with water.

Method for preparing tablets

Preferably, the tablets are prepared according to conventional tablet preparation methods. In this method, a homogenized dry powder is prepared by mixing the ingredients in a specific ratio. Subsequently, the powder is filled into a mold block and compressed to form a tablet. The powder may be compressed into tablets using a rotary press or a hydraulic press.

Preferably, the pressure applied during compression is in the range of 1-100 kg-f/cm ², more preferably 2-80 kg-f/cm ², even more preferably 3-60 kg-f/cm ², most preferably 4-50 kg-f/cm ².

Examples

Dry powder mixtures were prepared according to the formulations provided in table 1. In a subsequent step, each dry powder mixture of 10 gm was placed in a mold block and compressed by applying a pressure of 5 kg-f/cm ² to form tablets.

To evaluate the properties of the tablets prepared by the method, each tablet was added to 350 mL water and allowed to disintegrate and dissolve. The disintegration time of each tablet was recorded using a stopwatch. "disintegration time" herein refers to the time taken for a tablet to disintegrate into smaller pieces of less than 1 millimeter (about).

TABLE 1

Sodium linear alkylbenzene sulfonate from Unger Fabrikker AS (80% w/w activity).

Example 1 is a sodium cumene sulfonate (optionally as a hydrotrope) and sodium methyl cocoyl taurate according to the present invention, and example A, B is a comparative example. From the above, it is evident that the disintegration of example 1 is significantly faster than examples a and B.

Claims (13)

1. A unit-dose tablet comprising: a) 5 to 80% by weight of surfactants selected from anionic surfactants, nonionic surfactants, and combinations thereof; b) Aqueous co-solvents comprising alkyl aryl sulfonates having C1 to C5 alkyl chains; and c) Disintegrants, including water-soluble disintegrants having a solubility of at least 100 g/L in distilled water at 25°C. The surfactant comprises at least one anionic surfactant that is an alkyl cocoyl taurate. 2. The tablet of claim 1, wherein the tablet comprises 10 to 75% by weight of the anionic surfactant. 3. The tablet of claim 1 or 2, wherein the anionic surfactant is a combination of alkyl cocoyl taurate and at least one selected from primary alkyl sulfates, alkylbenzene sulfonates and alkyl ether sulfates. 4. The tablet according to any one of claims 1 to 3, further comprising a nonionic surfactant selected from alcohol ethoxylates, alkyl polysaccharides, and combinations thereof. 5. The tablet according to any one of claims 1 to 4, wherein the amount of the co-water solvent is in the range of 0.1 to 10% by weight of the tablet. 6. The tablet according to any one of claims 1 to 5, wherein the alkyl aryl sulfonate is selected from sodium xylenesulfonate, sodium toluenesulfonate, sodium isopropylbenzenesulfonate, potassium xylenesulfonate, potassium toluenesulfonate, potassium isopropylbenzenesulfonate, and combinations thereof. 7. The tablet of claim 6, wherein the alkyl aryl sulfonate is sodium isopropylbenzenesulfonate and/or sodium xylenesulfonate. 8. The tablet according to any one of claims 1 to 7, wherein the amount of the disintegrant is in the range of 10 to 90% by weight of the tablet. 9. The tablet of claim 8, wherein the water-soluble disintegrant comprises 50 to 100% by weight of the total weight of the disintegrant. 10. The tablet according to any one of claims 1 to 9, wherein the water-soluble disintegrant is selected from hydrated monosaccharides, hydrated disaccharides, hydrated oligosaccharides, and combinations thereof. 11. The tablet of claim 10, wherein the water-soluble disintegrant is glucose monohydrate. 12. A hard surface cleaner obtained by dissolving a tablet according to any one of claims 1 to 11 in water, wherein the weight ratio of the tablet to water is in the range of 1:5 to 1:100. 13. A method for cleaning a surface, comprising the following steps: a) Provide water in the container; b) Add and dissolve the tablets as described in any one of claims 1 to 11 in water. The tablets are in a water weight ratio in the range of 1:50 to 1:1000, thereby providing a liquid cleaning composition; and c) Apply the cleaning composition to the surface and clean it.