CN1333816A - Coloured tablet - Google Patents

Abstract

The present invention provides a detergent tablet comprising at least one coloured layer, whereby the colour is produced by a component having a function in cleaning. In a preferred embodiment, the coloured layer is coloured by a photo-bleach.

Description

Color chip

Technical Field

The present invention relates to detergent tablets.

Background

Detergent products are widely used as consumer products and are widely produced by industry. Most consumers desire detergent products with satisfactory aesthetics and ease of use. This has led, for example, to the development of a range of detergent products in solid form, commonly known as detergent tablets, some of which have only one layer and others are made up of several layers. Such detergent tablets may be coloured in order to maintain the basic requirements of the consumer. The colouring of detergent tablets is advantageous for increasing consumer acceptance, but the addition of ingredients such as dyes to such tablet compositions has certain drawbacks, the aesthetic effect of which is limited. Furthermore, the addition of dyes to detergent products increases the cost of the detergent product. In addition, in the specific example of laundry detergent tablets, such dyes can impart stains to clothes. It will also be appreciated that the production and use of dyes places an additional burden on the environment.

The present invention seeks to provide a sheet having at least one coloured layer in which at least some of the above-mentioned disadvantages are reduced.

Summary of The Invention

According to the invention, this object is achieved by a detergent tablet comprising at least one coloured layer, wherein the colour is produced by a component having a cleaning action.

Detailed Description

The detergent tablets of the invention comprise at least one coloured layer. By a detergent tablet it is understood that the tablet comprises a compound such as a surfactant that alters the surface tension of water. By a colored layer it is understood that the layer is not white.

Generally, according to the invention, color was measured using a chromameter.cr310 with MINOLTA set at an illumination/viewing angle of 0 ℃, using a standard light source C (average daylight does not include the uv wavelength region), this measurement being made for a 50mm diameter area.

This measurement can be carried out on a powder by placing 10-25g, preferably 25g, of the powder in a beaker having a height of 10cm and a diameter of 50mm, at a temperature of 20 ℃ and placing the beaker on a light projection tube. The measurement can be performed directly on the sheet, for example with a weight of 54g of sheet, on which the light projector is placed.

This measurement yielded three values, L, a and b, as illustrated in FIG. 1.

The L value is a measure of the black/white scale. When white is complete, L is 100, when black is complete, L is 0, and the value of L varies between these.

Similarly, the a value reports the green/red scale metric. Completely green, a-80, completely red, a-100, with a values varying between.

Finally, the b-value reports the measure of the blue/yellow scale. Completely blue, b-80, and completely yellow, b-70.

This L, a, b scale is available from Hunter Lab 11491 Sunset hillsRoad, Reston, VA22090, USA.

The standard deviation of this assay was 0.07 when using the chemo meter. cr310 of MINOLTA.

For the purposes of the present invention, "white" is understood to mean the color measured when the values of a and b are close to 0. It should be appreciated that in the "white" case, it is acceptable for a to be slightly positive for the b value. The following ranges are typical: one assay reported that a was between-6 and 6, b was between-6 and 12, and L was greater than 50, which was considered white. More preferred ranges are a between-3 and 3, b between-3 and 10, and L is greater than 70.

For example, one assay reported a-9, b +3 and L-80, which were considered green, shifted slightly to yellow.

It is also to be understood that the color of the layer is preferably a uniform color wherein there is no L, a and b value difference as measured between any distinct apparent portions of the colored layer each representing at least 3% of the total surface area of the colored layer of greater than 50%, preferably 40%, more preferably 30%, most preferably 10%.

According to the invention, the colour is produced by a component having a cleaning action. A component having a cleaning action is understood to mean a component which is directly or indirectly active for removing stain soils or for caring for fabrics.

Direct activity means directly related to soil or stain removal, which includes for example surfactants, bleaching substances or enzymes, or directly for fabric care, including for example fabric softeners, dye transfer inhibitors.

Indirect activity means that the component is for example advantageous for the activity of a direct active component, as is the case for builders, for example.

Highly soluble compounds, hydrotrope compounds, compounds with binding action, coating compounds, sudsing compounds, binders, non-gelling binders, chelating agents, soil release agents, soil antiredeposition agents, dispersants.

Compounds which are not directly or indirectly active for cleaning, such as perfumes or dyes, are not included here. In fact, these ingredients have purely aesthetic activity.

In fact, the advantage of the invention is that the colour of the coloured layer is produced by the component having a cleaning action and not by the dye. It should be recognized that a small amount of dye may be included to adjust the aesthetics of the colored layer. However, the main coloured component is produced by the component having a cleaning action. By modulation, it is understood that the a, b or L values may vary by several units, typically about 3-5 units. In a preferred embodiment, the color of the color chip is produced by a mixture of components having a cleaning action.

This allows the production of preferred tablets of the invention without dye.

The sheet of the present invention preferably comprises a binder. Such binders can be sprayed onto the substrate, for example together with components having a cleaning action and producing color and optionally with brightener components, for example before the substrate is pressed into the form of a tablet.

The brightener component can also be added as a dry component to a layer containing a greater amount of brightener component than the other layers before the adhesive is sprayed on.

In fact, a preferred method for preparing the tablets of the invention is a method for preparing tablets as claimed in claim 1, wherein in a first step the ingredients having a cleaning action are mixed with a non-ionic carrier, sprayed onto a specific product in a second step, and the specific product is compressed into tablets in a third step, the non-ionic carrier preferably being a binder, such as polyethylene glycol.

In a further preferred embodiment of the invention, the sheet has a tensile strength of less than 100 kPa. In fact, the tablets are preferred for use in laundry applications, for example where low tensile strength favors dissolution when compared to automatic dishwashing tablets. In fact, high levels of dye in laundry tablets can lead to staining of the garment, and the tablets of the invention avoid this problem. Even more preferred are coated sheets. In fact, the present invention and the coated sheet should have a color that is visible through the coating. For the usual dye technology, this means that high levels of dye are used, thereby increasing the risk of soiling the clothing. Therefore, the present invention is particularly advantageous in such a case. Even more particularly, it applies to situations where a photo-bleach is used to produce a color, wherein the photo-bleach will fade its color when exposed to light, thereby also limiting soiling of clothing. This also means that when using photobleaches the detergent tablets should be stored in a package that does not allow light to penetrate in order to avoid decomposition of the photobleach and loss of colour. This can be achieved, for example, by using a carton or a metal foil. Most preferably, the sheet comprising the coloured layer produced by the photo-bleach is placed in a packaging system which inhibits at least partial and preferably all transmission of UV light.

In a preferred embodiment of the invention, the sheet comprises at least two coloured layers and at least one further layer is white. This is preferably achieved when the white layer contains a larger amount of the brightener component than the other layer. The whitening agent is typically a fluorescent whitening agent. Examples of the whitening agent include:

4, 4' -bis { [ 4-anilino-6- [ bis (2-hydroxyethyl) amino-s-triazin-2-yl]-disodium amino } -2, 2' -stilbene disulphonate, MW 914;

4, 4' -bis { [ 4-anilino-6-morpholino-s-triazin-2-yl]-disodium amino } -2, 2' -stilbene disulphonic acid, MW 924;4, 4' -bis [ (4, 6-dianilino-s-triazin-2-yl) -amino]-disodium 2, 2' -stilbenedisulfonate;

4, 4' -bis (2-sulfostyryl) biphenyl disodium MW 562(Na salt):

in fact, it was found that higher concentrations of the brightener component lead to higher L values, thus improving the contrast between the colored and white layers. In a more preferred embodiment of the present invention, the contrast is further improved, wherein the white layer comprises a smaller amount of coloured component, even more preferably does not contain any coloured component.

The presence of a larger amount in one layer than in the other layers is to be understood as meaning a larger amount by weight of the component, preferably 1% more by weight of this component in one layer than in the other layers, more preferably more than 10%, even more preferably more than 50%, most preferably the other layers do not comprise this component at all, but only one layer. Smaller amounts are defined exactly the opposite way.

In another preferred embodiment of the invention, the sheet comprises at least two coloured layers, and at least one further layer has a different colour.

In a preferred embodiment of the invention, the component having a cleaning action is a coloured photo-bleach, which produces a colour. Photobleaches are generally compounds which produce an oxide which oxidizes double bonds. It will be appreciated that the production of oxides is typically triggered by light (so named photobleach). Typically, photobleaches have a color. Extensive research has been carried out in the industry to develop photobleaches that do not produce a visible color, as such visible color is believed to interfere with the aesthetics of the detergent, which is typically avoided by encapsulation of the photobleach. However, it has been found according to the present invention that such a colour can be advantageously used for dyeing the layer, thereby avoiding the use of dyes. This also has the advantage that non-encapsulated photo-bleaches can be used. In fact, the photobleach in the preferred embodiment of the present invention is not encapsulated, but is preferably sprayed onto the detergent composition substrate together with the binder.

Photobleach compounds include the following: zinc phthalocyanine tetrasulfonate. Formula weight 986

Other metal phthalocyanines may also be used.

The tablet may contain ingredients such as perfumes, surfactants, enzymes, detergents, and the like. Typical tablet compositions of preferred embodiments of the present invention are disclosed in, for example, applicants' unpaired european applications n ° 96203471.6, 96203462.5, 96203473.2 and 96203464.1. The ingredients typically incorporated into detergent tablets or other forms of detergents such as liquid or granular compositions are described in detail in the following paragraphs. Highly soluble compounds

The tablet may contain a highly soluble compound. Such compounds may be prepared from mixtures or from a single compound. Highly soluble compounds are defined as follows:

a solution containing deionized water and 20g of the specified compound per liter was prepared as follows:

1-20 g of the particular compound were placed in a Sotax beaker. The beaker was placed in a constant temperature bath fixed at 10 ℃. The stirrer with marine propeller was placed in the beaker with the bottom of the stirrer 5mm above the bottom of the Sotax beaker. The rotational speed of the mixer was fixed at 200 revolutions per minute.

2-980 g of deionized water was added to the Sotax beaker.

3-conductivity of the solution was measured using a conductivity meter 10 seconds after the water injection.

4-repeat step 3 after 20, 30, 40, 50 seconds, 1 minute, 2 minutes, 5 minutes and 10 minutes after step 2.

5-the measurement taken at 10 minutes was taken as the plateau or maximum.

The particular compound is highly soluble according to the invention when the conductivity of the solution reaches 80% of its maximum value in less than 10 seconds, starting with the addition of deionized water to the compound. In fact, when the conductivity is monitored in this way, the conductivity levels off over a period of time, this plateau value being considered as the maximum value. This compound is preferably in the form of a flowable material consisting of solid particles which are easy to handle at 10-80 ℃, but other forms may be used, such as a paste or liquid.

Examples of the highly soluble compound include sodium diisoalkylbenzene sulfonate or sodium toluene sulfonate. Bonding action

The tablet may contain a compound which has a binding effect on the particulate material of the detergent matrix from which the tablet is made. The binding action on the granular material of a detergent matrix made into tablets or sheets is characterized by the force required to break up the tablet or layer, which is based on the detergent matrix being tested pressed under controlled pressure conditions. For a given pressure, a high strength of the sheet or layer indicates that the particles are highly bonded together when pressed, so a strong bonding action occurs. Method of assessing the strength of a sheet or layer (also known as radial rupture stress) is given in a pharmaceutically acceptable dosage form: tablets, volume 1, editor h.a. lieberman et al, published in 1989.

The cohesion is determined by comparing the strength of a sheet or layer of the raw base powder without the compound having cohesion with the strength of a sheet or layer of a powder mixture comprising 97 parts of raw base powder and 3 parts of the compound having cohesion. The compound having a binding action is preferably added to the matrix in a substantially anhydrous form (water content below 10% (preferably below 5%)). The temperature of addition is 10-80 deg.C, more preferably 10-40 deg.C.

A compound having a weight of 50g detergent particulate material and a diameter of 55mm is defined as having a binding effect on the particulate material of the invention when the tensile strength of the tablet is increased by more than 30% (preferably 60%, more preferably 100%) in the presence of 3% of the compound having a binding effect on the base particles at a given pressure of 3000N.

An example of a compound having a binding action is sodium diisoalkylbenzene sulphonate.

When a highly soluble compound is combined which also has a binding effect on the particulate material used for the tablet or layer, which is made by compressing a surfactant-containing particulate material, the dissolution of the tablet or layer in an aqueous solution is significantly increased. In a preferred embodiment at least 1% by weight of the tablet or layer is made of a highly soluble compound, more preferably at least 2%, even more preferably at least 3%, most preferably at least 5% by weight of the tablet or layer is made of a highly soluble compound having a binding effect on the particulate material.

It is noted that compositions comprising highly soluble compounds and surfactants are disclosed in EP-A-524075, which compositions are liquid compositions.

The highly soluble compound having a binding effect on the particulate material enables tablets having higher tensile strength to be obtained at a constant pressure or equivalent tensile strength to be obtained at a lower pressure when compared with conventional tablets. Generally, the entire sheet has a tensile strength of greater than 5kPa, preferably greater than 10kPa, more preferably, especially for use in laundry applications, greater than 15kPa, even more preferably greater than 30kPa and most preferably greater than 50kPa, especially for dishwashing or automatic dishwashing applications; the tensile strength is below 300kPa, preferably below 200kPa, more preferably below 100kPa, even more preferably below 80kPa, most preferably below 60 kPa. In fact, in laundry applications the compressed tablet should be slightly weaker than in e.g. automatic dishwashing applications, and thus more soluble, so the tensile strength is preferably below 30kPa in laundry applications.

This enables the robustness and mechanical resistance of the resulting tablet or layer to be compared with that of conventional tablets, whilst the tablet or layer is low-compressed and therefore more readily soluble. In addition, since the compound is highly soluble, dissolution of the tablet or layer is also promoted, resulting in a synergistic effect that promotes dissolution of the tablet of the present invention. Preparation of tablets

The sheet may comprise several layers. For the preparation of a monolayer, the layer may be considered to be the sheet itself.

Detergent tablets may be prepared by simply mixing the solid components together and compressing the mixture using a conventional tablet press as used in the pharmaceutical industry, for example. Preferably, the major component, especially the gelling surfactant, is used in particulate form. Any liquid component, such as a surfactant or suds suppressor, can be incorporated into the solid particulate component in a conventional manner.

In particular for laundry tablets, ingredients such as builders and surfactants can be spray-dried by conventional methods and then compressed at appropriate pressures. Preferably, the tablets of the invention are compressed with a force of less than 100000N, more preferably less than 50000N, even more preferably less than 5000N, most preferably less than 3000N. In fact, the most preferred embodiment is tablets pressed with a force below 2500N suitable for laundry, but for example tablets for automatic dishwashing are also contemplated whereby such automatic dishwashing tablets are typically pressed more strongly than laundry tablets.

For preparing tabletsThe particulate material of (a) may be prepared by any granulation or prilling method. An example of such a process is spray drying (in co-current or counter-current spray drying towers), which generally results in a low bulk density of 600g/l or less. By granulation and densification in a high shear batch mixer/granulator or by a continuous granulation and densification process (e.g. using Lodige)^®CB and/or Lodige^®KM mixer) can produce higher density particulate materials. Other suitable processes include fluidized bed processes, compression processes (e.g., roller compression), extrusion, and the preparation of any particulate material by chemical processes such as flocculation, crystallization, and the like. The particles may also be any other particulate, granular, prill or granule.

The components of the particulate material may be mixed together in any conventional manner, with batch processes being suitable, for example, for concrete mixers, Nauta mixers, ribbon mixers or any other equipment. Alternatively, the mixing process may be carried out continuously by metering the weight of the components onto a moving belt and mixing them by stirring in one or more drums or mixers. A non-gelling binder may be sprayed onto some or all of the mixture of particulate material components. Other liquid components may also be sprayed onto the mixture of the individual or premixed components. For example, perfume and optical brightener slurries can be sprayed. Preferably towards the end of the process, a finely divided flow aid (release agent such as zeolite, carbonate, silica) is added to the particulate material after spraying the binder to render the mixture less viscous.

The tablets may be prepared by any compression method, for example tabletting, briquetting or extrusion, preferably tabletting. Suitable equipment includes standard single stroke or rolling presses (e.g., Courtoy)^®，Korch^®，Manesty^®Or Bonals^®). The tablets prepared according to the invention preferably have a diameter of 20mm to 60mm, preferably at least 35 and up to 55mm, and a weight of between 25 and 100 g. The ratio of the height to the diameter (or width) of the tablet is preferably greater than 1: 3, more preferably greater than 1: 2. The pressure used for preparing the tablets should not exceed 100000kN/m²Preferably not more than 30000kN/m²More preferably not more than 5000kN/m²And even more preferably not more than 3000kN/m²Most preferably not more than 1000kN/m². In a preferred embodiment of the invention, the tablet has a density of at least 0.9g/cc, more preferably at least 1.0g/cc, preferably less than 2.0g/cc, more preferably less than 1.5g/cc, even more preferably less than 1.25g/cc, most preferably less than 1.1 g/cc.

Multilayer sheets are typically made by placing the individual layers of the substrate one after the other in a tank (flashes) of pressure-fed substrate in a rotary die press. As the process continues, the substrate layers are then pressed together in a pre-press and press stage to form a multi-layer sheet. For some rotary presses, it is also possible to press a first layer of feed material and then press the entire sheet.

Hydrotrope compounds

Highly soluble compounds with a binding effect may be incorporated into the detergent tablet, wherein such compounds may also be hydrotrope compounds. Typically such hydrotrope compounds facilitate the solubilization of the surfactant by avoiding gelling. Specific compounds are hydrotropes defined as follows (see s.e. friberg and m.chiu, journal of dispersion Science and Technology, 9(5&6), pages 443-457 (1988-):

1. a solution was prepared comprising 25% by weight of the specified compound and 75% by weight of water.

2. Octanoic acid was then added to the solution at a temperature of 20 c at 1.6 times the weight of the particular compound in the solution. The solution was mixed in a Sotax beaker with a stirrer with a marine propeller positioned about 5mm above the bottom of the beaker, the speed of the mixer was fixed at 200 revolutions per minute.

3. If the octanoic acid is completely dissolved, i.e. if the solution comprises only one phase, which is a liquid phase, the specific compound is a hydrotrope.

It is noted that in a preferred embodiment of the invention, the hydrotrope compound is a material made from solid particles that is flowable at operating conditions of 15-60 ℃.

Hydrotrope compounds include the compounds listed below:

a list of commercially available hydrotropes can be found in the emulsifier and detergent of McCutcheon, published by the McCutcheon division of Confectioners preparations. Interesting compounds also include:

1. a nonionic hydrotrope having the structure:

R-O-(CH2CH2O)x(CH-CH2O)yH

CH3

2. anionic hydrotropes such as alkali metal aryl sulphonates. This includes alkali metal benzoates, salicylates, benzenesulfonates and many of their derivatives, naphthalates, and various hydroaromatics. Examples of these are sodium, potassium and ammonium benzenesulfonates derived from toluenesulfonic acid, xylenesulfonic acid, isopropylbenzenesulfonic acid, 1, 2, 3, 4-tetrahydronaphthalenesulfonic acid, naphthalenesulfonic acid, methylnaphthalenesulfonic acid, dimethylnaphthalenesulfonic acid, trimethylnaphthalenesulfonic acid.

Other examples include dialkyl benzene sulfonates such as diisopropylbenzene sulfonate, ethylmethyl benzene sulfonate, alkylbenzene sulfonates having an alkyl chain length of 3 to 10 (preferably 4 to 9) carbon atoms, and straight or branched alkyl sulfonates having an alkyl chain of 1 to 18 carbon atoms.

3. Solvent hydrotropes such as alkoxylated glycerol and alkoxylated glycerides, ester alkoxylated glycerol, alkoxylated fatty acids, glycerides, polyglycerides. Preferred alkoxylated glycerols have the following structure:wherein l, m and n are each a number from 0 to about 20, l + m + n is from about 2 to about 60, preferably from about 10 to about 45, and R represents H, CH₃Or C₂H₅。

Preferred alkoxylated glycerides have the following structure:wherein R1 and R2 are each C_nCOO or- (CH)₂CHR₃-O)₁-H, wherein R₃＝H、CH₃Or C₂H₅L is a number from 1 to about 60 and n is a number from about 6 to about 24.

4. Polymeric hydrotropes such as those described in EP 636687:

wherein E is a hydrophilic functional group, wherein,

r is H or C1-C10 alkyl or a hydrophilic functional group;

r1 is H or lower alkyl or aryl;

r2 is H or cycloalkyl or aryl.

The polymer typically has a molecular weight of about 1000-.

5. Hydrotropes of unusual structure, for example 5-carboxy-4-hexyl-2-cyclohexen-1-yl octanoic acid (Diacid).

The use of such compounds in the present invention further increases the dissolution rate of the tablet because the hydrotrope compound facilitates the dissolution of, for example, surfactants. Such compounds may be prepared from mixtures or from single compounds.

Coating layer

By preparing the coated tablets, the robustness of the tablets can be improved, the coating covering the uncoated tablets, thereby further improving the mechanical properties of the tablets while maintaining or further improving dissolution.

This is very advantageous for use in multilayer sheets, where the mechanical properties of the more elastic layer are transferred to the rest of the sheet through the coating, thereby combining the advantages of the coating with the advantages of the more elastic layer, in fact, mechanical binding will be transferred through the coating, thereby improving the mechanical integrity of the sheet.

In one embodiment of the invention, the sheet may then be coated so that the sheet does not absorb water or only absorbs water at a very slow rate. The coating is also strong such that the sheet is subjected to moderate mechanical impact during handling, packaging and shipping resulting in no more than a very low amount of breakage or wear. Finally, the coating is preferably frangible so that the sheet breaks when subjected to strong mechanical impact. In addition, it is advantageous if the coating material dissolves under alkaline conditions or is easily emulsified by surfactants. This helps to avoid the problem of residues visible during the washing stage adhering to the window of the front-loading washing machine and also avoids undissolved particles or lumps of coating material being deposited on the washed load.

Water solubility was determined using the following ASTM E1148-87, test protocol entitled "Standard test methods for determining Water solubility".

Suitable coating materials are dicarboxylic acids. Particularly suitable dicarboxylic acids are selected from oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, sebacic acid, undecanedioic acid, dodecanedioic acid, tridecanedioic acid and mixtures thereof.

The coating material has a melting point preferably in the range of 40 ℃ to 200 ℃.

The coating may be applied in a variety of ways. Two preferred coating methods are a) coating with a molten material and b) coating with a solution of the material.

In a), the coating material is applied and cured on the sheet at a temperature above its melting point. In b), the coating material is applied as a solution and the solvent is dried, leaving a coherent coating. The substantially insoluble material may be applied to the sheet by, for example, spraying or dipping. Typically, when the molten material is sprayed onto the sheet, it quickly solidifies to form an adherent coating. Rapid solidification of the coating material can be caused when the sheet is dipped into the molten material, then removed, and rapidly cooled. It is clear that substantially insoluble materials having a melting point below 40 c are not sufficiently curable at room temperature and that materials having a melting point above about 200 c have not been found to be practical. Preferably, the melting point of the material is between 60 ℃ and 160 ℃, more preferably between 70 ℃ and 120 ℃.

By "melting point" is meant the temperature at which the material becomes a transparent liquid when heated slowly in, for example, a capillary.

Any desired thickness of the coating may be applied according to the present invention. For most purposes, the coating will comprise from 1% to 10%, preferably from 1.5% to 5% by weight of the tablet.

The tablet coating is very hard and provides additional strength to the tablet.

The cracking of the coating in the wash can be improved by adding a disintegrant to the coating. The disintegrant swells upon contact with water and breaks the coating into small pieces. This will improve the dissolution of the coating in the wash solution. The amount of disintegrant suspended in the coating melt is up to 30%, preferably 5% to 20%, most preferably 5% to 10% by weight. Possible disintegrants are described in the handbook of pharmaceutical excipients (1986). Examples of suitable disintegrants include starch; native, modified or pregelatinized starches; starch sodium gluconate; a gum; agar gum; guar gum; locust bean gum; karaya gum; pectin; gum tragacanth; croscarmylose Sodium, polyvinyl polypyrrolidone, cellulose, carboxymethylcellulose, alginic acid (algenic acid) and salts thereof, including Sodium alginate, silica, clays, polyvinyl pyrrolidone, soy polysaccharides, ion exchange resins, and mixtures thereof.

Tensile strength

To determine the tensile strength of a layer, the layer can be considered to be the sheet itself.

Depending on the composition of the raw material and the shape of the tablet, the pressure used can be adjusted without affecting the tensile strength and the disintegration time in the washing machine. The process can be used to prepare uniform or layered tablets of any size or shape.

For cylindrical sheets, tensile strength is equivalent to radial fracture stress (DFS), which is one way to express the strength of a sheet or layer, determined by the following equation:

tensile strength 2F/pi Dt

Where F is the maximum force (Newton) causing loss of tension (rupture) as determined using a VK 200-piece hardness tester supplied by Van Kellinddustries, Inc. D is the diameter of the sheet or layer and t is the thickness of the sheet or layer. For non-circular patches, π D can simply be replaced by the patch's circumference. (pharmaceutical dosage form method: tablet, volume 2, page 213-217).

Sheets having a radial rupture stress below 20kPa are considered brittle and may result in some breakage of the sheet to the consumer. Preferably the radial rupture stress is at least 25 kPa.

The same applies to non-cylindrical sheets where the cross-section perpendicular to the height of the sheet is not circular and where forces are applied in a direction perpendicular to the height of the sheet and perpendicular to the side of the sheet that is perpendicular to the non-circular cross-section to determine tensile strength.

Dispensing of tablets

The dispensing speed of the detergent tablet can be determined as follows:

two pieces, each nominally 50 grams, were weighed into a dispenser of Baucknecht WA9850 washer. The water temperature to the washer was fixed at 20 c and the hardness was 21 grains/gallon, and the inlet water flow rate to the dispenser was fixed at 81/min. The power to the washing machine was switched on and the wash cycle was set to wash program 4 (white/color, short cycle), checking the amount of tablet residue remaining in the dispenser. The percentage dispensed was determined as follows:

% distribution-weight of residue X100/weight of original sheet

This procedure was repeated 10 times to determine the residue content and the average residue content was calculated from the 10 measurements. In this stress test, a residue of 40% by weight of the starting sheet was considered acceptable. Preferably less than 30% residue, more preferably less than 25%.

It is noted that the measure of water hardness is given in the traditional "grains/gallon" unit, where 0.001 moles/liter to 7.0 grains/gallon represents Ca²⁺Concentration of ions in solution.

Foaming agent

The detergent tablet may also comprise a foaming agent.

Foaming, as defined herein, means that carbon dioxide gas is generated as a result of a chemical reaction between a soluble acid source and an alkali metal carbonate, resulting in gaseous bubbles emanating from the liquid,

namely, it is

Additional examples of acid and carbonate sources and other blowing agent systems can be found in: (pharmaceutical dosage form: sheet, volume 1, page 287-291).

In addition to the detergent component, a sudsing agent may be added to the tablet mixture. The addition of sudsing agents to detergent tablets improves the disintegration time of the tablets. Preferably in an amount of from 5% to 20%, most preferably from 10% to 20% by weight of the tablet. Preferably, the blowing agent should be added as an agglomerate of different particles or as a compact, rather than as a separate particle.

Because blistering in the sheet generates gases, the sheet may have a higher d.f.s., but still have the same disintegration time as a non-blistering sheet. The foamed sheet decomposed faster when the d.f.s. of the foamed sheet remained the same as the non-foamed sheet.

Additional dissolution aids may be provided by the use of compounds such as sodium acetate or urea. A list of suitable dissolution aids can also be found in pharmaceutically acceptable dosage forms: sheets, volume 1, version 2, compiled by H.A. Lieberman et al, ISBN 0-8247-.

Detersive surfactant

Surfactants are typically included in detergent compositions. By adding a highly soluble compound, the dissolution of the surfactant is facilitated.

Non-limiting examples of surfactants suitable for use in the present invention generally comprise from about 1% to about 55% by weight, including conventional C₁₁-C₁₈Alkyl benzene sulfonates ("LAS"), and branched primary and random C₁₀-C₂₀Alkyl sulfates ("AS"), formula CH₃(CH₂)_x(CHOSO₃ ^-M⁺)CH₃And CH₃(CH₂)_y(CHOSO₃ ^-M⁺)CH₂CH₃C of (A)₁₀-C₁₈Secondary (2, 3) alkyl sulfates wherein x and (y + 1) are integers of at least about 7, preferably at least about 9, M is a water-soluble cation, particularly sodium, an unsaturated sulfate such as oleyl sulfate, C₁₀-C₁₈Alkyl alkoxy sulfates (' AE)_XS "; in particular EO1-7 ethoxy sulfate), C₁₀-C₁₈Alkyl alkoxy carboxylates (especially EO1-5 ethoxy carboxylates), C₁₀-C₁₁Glycerol ethers, C₁₀-C₁₈Alkyl polyglycosides and their corresponding sulfated polyglycosides, and C₁₂-C₁₈α -sulfonated fatty acid ester if desired, conventional nonionic and amphoteric surfactants such as C may also be included in the overall composition of the invention₁₂-C₁₈Alkyl ethoxylates ("AE") including so-called narrow peak distribution (narrow) alkyl ethoxylates and C₆-C₁₂Alkylphenol alkoxylates (in particular ethoxylatesBases and mixed ethoxy/propoxy compounds), C₁₂-C₁₈Betaines and sulfobetaines, C₁₀-C₁₈Amine oxides, and the like. Also usable are C₁₀-C₁₈N-alkyl polyhydroxy fatty acid amides, typical examples include C₁₂-C₁₈N-methylglucamide. See WO9,206,154. Other saccharide-derived surfactants include N-alkoxy polyhydroxy fatty acid amides, e.g. C₁₀-C₁₈N- (3-methoxypropyl) glucamide. When low foaming is desired, N-propyl to N-hexyl C may be used₁₂-C₁₈A glucamide. Also usable are C₁₀-C₂₀Conventional soaps. If high foaming is desired, it is possible to use branches C₁₀-C₁₆Soap. Mixtures of anionic and nonionic surfactants are particularly useful. Other conventionally useful surfactants are listed in standard textbooks. In a preferred embodiment, the tablet comprises at least 5 wt% surfactant, more preferably at least 15 wt%, even more preferably at least 25 wt%, most preferably from 35% to 45 wt% surfactant.

Non-gelling binders

To further facilitate dissolution, a non-gelling binder may be incorporated into the detergent composition.

If a non-gelling binder is used, suitable non-gelling binders include synthetic organic polymers such as polyethylene glycol, polyvinylpyrrolidone, polyacrylates, and water-soluble polyacrylate copolymers. The pharmaceutical excipients handbook, second edition, lists the following types of binders: gum arabic, alginic acid, acrylic acid polymers, sodium carboxymethylcellulose, dextrin, ethylcellulose, gelatin, guar gum, hydrogenated vegetable oil type 1, hydroxyethyl cellulose, hydroxypropyl methylcellulose, liquid glucose, magnesium aluminum silicate, maltodextrin, methylcellulose, polymethacrylates, povidone (povidone), sodium alginate, starch, and zein. Most preferred binders also have a cleaning action active in laundry, for example cationic polymers, i.e. ethoxylated hexamethylene diamine quaternary ammonium compounds, bis hexamethylene triamine or other substances such as pentamines, ethoxylated polyethylene amines, maleic acrylic polymers.

Preferably sprayed with a non-gelling binder material, whereby it has a suitable melting point below 90 c, preferably below 70 c, even more preferably below 50c, so as not to destroy or degrade the other active components in the matrix. Most preferred are non-aqueous liquid binders (i.e., not in aqueous solution) which can be sprayed in molten form. However, they may also be solid adhesives which are incorporated into the matrix by dry addition, but which have adhesive properties in the sheet.

The non-gelling binder material is preferably used in an amount of from 0.1% to 15%, more preferably less than 5%, especially less than 2% by weight of the tablet if it is a non-laundry active.

The use of gelling binders, such as nonionic surfactants, in liquid or molten form is preferably avoided. Nonionic surfactants and other gelling binders are not excluded from the composition, but preferably they are processed into the detergent tablet as a component of the particulate material, rather than as a liquid.

Builder

Detergent builders may optionally be included in the compositions of the present invention to assist in controlling mineral hardness. Inorganic and organic builders can be used. Builders are commonly used in compositions for laundering fabrics to aid in the removal of particulate soils.

The level of builder may vary over a wide range depending on the end use of the composition.

Inorganic or phosphorous containing builders include, but are not limited to: polyphosphates (exemplified by tripolyphosphates, pyrophosphates, and glassy polymeric metaphosphates), phosphonates, phytates, silicates, carbonates (including bicarbonates and sesquicarbonates), sulfates, and aluminosilicates. However, non-phosphate builders are required in certain areas. Importantly, the efficacy of the compositions of the present invention is unexpectedly good even in the presence of so-called "weak" builders (as compared to phosphates), such as citrate, or in so-called "low built" situations which can occur when zeolite or layered silicate builders are used.

Examples of silicate builders are alkali metal silicates, especially those having SiO₂∶Na₂Silicates and layered silicates having a ratio of O in the range of 1.6: 1 to 3.2: 1, such as the layered sodium silicate described in US patent US4664839 to h.p. rieck, granted 5/12 in 1987. NaSKS-6 is a trademark of layered crystalline silicates sold by Hoechst (generally abbreviated herein as "SKS-6"). Unlike zeolite builders, NaSKS-6 silicate builders do not contain aluminum. NaSKS-6 is a compound having delta-Na₂SiO₅A layer silicate in a morphological form. They can be prepared by processes such as those described in DE-A-3417649 and DE-A-3742043. SKS-6 is the highly preferred layered silicate for use herein, but other layered silicates, such as those having the general formula NaMSi, can be used in the present invention_xO_2x＋1·yH₂Layered silicates of O, where M is sodium or hydrogen, x has a value of 1.9 to 4, preferably 2, and y has a value of 0 to 20, preferably 0 various other layered silicates available from Hoechst include NaSKS-5, NaSKS-7, and NaSKS-11, in the form of α, β, and γ₂SiO₅(NaSKS-6 form) is most preferred for use herein. Other silicates are also useful, such as magnesium silicate, as a crispening agent for granule formulations, as a stabilizer for oxygen bleaches, and as a component of foam control systems.

Examples of carbonate builders are the alkaline earth and alkali metal carbonates of German patent application 2321001 published on 11/15/1973.

Aluminosilicate builders are useful in the present invention. Aluminosilicate builders are of primary importance in the most commonly marketed heavy-duty granular detergent compositions, and can also be an important builder component in liquid detergent formulations. Aluminosilicate builders include builders having the empirical formula:

M_z(zAlO₂)_y].xH₂O

wherein z and y are integers of at least 6, the molar ratio of z to y is in the range of 1.0 to about 0.5, and x is an integer of about 15 to about 264.

Useful aluminosilicate ion exchange materials are commercially available. These aluminosilicates may be of crystalline or amorphous structure and may be naturally occurring aluminosilicates or synthetically derived. A process for preparing aluminosilicate ion exchange materials is disclosed in U.S. Pat. No. 3,3985669 to Krummel et al, issued 10/12/1976. Preferred synthetic crystalline aluminosilicate ion exchange materials for use herein are commercially available under the designations zeolite a, zeolite p (b), zeolite MAP and zeolite X. In a particularly preferred embodiment, the crystalline aluminosilicate ion exchange material has the formula:

Na₁₂[(AlO₂)₁₂(SiO₂)₁₂].xH₂O

wherein x is from about 20 to about 30, especially about 27. This material is referred to as zeolite a. Dehydrated zeolites (x ═ 0 to 10) may also be used herein. The aluminosilicate preferably has a particle size of about 0.1 to 10 microns in diameter.

Organic detergent builders suitable for the purposes of the present invention include, but are not limited to: various polycarboxylate compounds. As used herein, "polycarboxylate" refers to a compound having a plurality of carboxylic acid groups, preferably at least 3 carboxylic acid groups. Polycarboxylate builders can generally be added to the compositions in the acid form, but can also be added in the form of neutralized salts. When used in the form of a salt, alkali metal salts such as sodium, potassium and lithium or alkanolammonium salts are preferred.

A variety of useful materials are included in polycarboxylate builders. One important class of polycarboxylate builders includes the ether polycarboxylates, including oxydisuccinates, such as those disclosed in U.S. Pat. No. 3,3128287 to Berg, granted on 4/7 in 1964, and U.S. Pat. No. 3635830 to Lamberti et al, granted on 1/18 in 1972. See also U.S. patent US4663071 to Bush et al entitled "TMS/TDS" builder on 5.5.1987. Suitable ether polycarboxylates also include cyclic compounds, particularly cycloaliphatic compounds, as described in US 3923679; US 3835163; US 4158635; those described in US4120874 and US 4102903.

Other useful lotion builders include ether hydroxypolycarboxylates, copolymers of maleic anhydride with ethylene or vinyl methyl ether, 1, 3, 5-trihydroxybenzene-2, 4, 6-trisulfonic acid, and carboxymethoxysuccinic acid, alkali metal, ammonium and substituted ammonium salts of various polyacetic acids, such as ethylenediaminetetraacetic acid and nitrilotriacetic acid, and polycarboxylic acids, such as mellitic acid, succinic acid, oxydisuccinic acid, polymaleic acid, benzene-1, 3, 5-tricarboxylic acid, carboxymethoxysuccinic acid, and soluble salts thereof.

Citrate builders, for example, citric acid and soluble salts thereof (especially sodium salts) are polycarboxylate builders of particular importance in heavy duty liquid detergent formulations because they are available from renewable resources and their biodegradability. Citrate salts may also be used in granular compositions, particularly in combination with zeolite and/or layered silicate builders. Oxydisuccinates are also particularly useful in such compositions and mixtures.

Also suitable for use in the detergent compositions of the present invention are 3, 3-dicarboxy-4-oxa-1, 6-adipate salts and related compounds disclosed in U.S. patent number US4566984 to Bush, issued on 28.1.1986. Useful succinic acid builders include the C5-C20 alkyl and alkenyl succinic acids and their salts. A particularly preferred compound of this type is dodecenylsuccinic acid. Specific examples of succinate builders include: lauryl succinate, myristyl succinate, palmityl succinate, 2-dodecenyl succinate (preferred), 2-pentadecenyl succinate, etc. Lauryl succinate is a preferred builder in this group and is described in European patent application 86200690.5/0200263 published on 5.11.1986.

Other suitable polycarboxylates are disclosed in U.S. Pat. No. 4,44226 to Crutchfield et al, granted on 3/13 1979, and U.S. Pat. No. 3308067 to Diehl, granted on 3/7 1967. See also U.S. Pat. No. 3,3723322 to Diehl.

Fatty acids, e.g. C₁₂-C₁₈Monocarboxylic acids, either alone or in combination with the foregoingIn particular citrate and/or succinate builders, are incorporated in combination in the compositions to provide additional builder activity. The use of fatty acids generally results in impaired foaming, which the formulator should consider.

Where phosphorus containing builders can be used, especially in bar formulations for hand washing operations, various alkali metal phosphates such as the well known sodium tripolyphosphates, pyrophosphates and orthophosphates can be used. Phosphonate builders such as ethane-1-hydroxy-1, 1-diphosphonate and other well known phosphonates may also be used (see, for example, U.S. Pat. Nos. 3159581; 3213030; 3422021; 3400148 and 3422137).

Bleaching agent

The detergent compositions of the present invention may optionally contain a bleaching agent or a bleaching composition comprising a bleaching agent and one or more bleach activators. When present, bleaching agents are generally present at levels of from about 1% to about 30%, more typically from about 5% to about 20% of the detergent composition, especially for laundering fabrics. If included, the bleach activator is typically present at a level of from about 0.1% to about 60%, more preferably from about 0.5% to about 40%, of the bleaching composition comprising the bleach and the bleach activator.

The bleaching agent used herein may be any bleaching agent suitable for use in detergent compositions for cleaning fabrics, cleaning hard surfaces, or other cleaning applications now known or to be known. These include oxygen bleaches as well as other bleaching agents. Perborate bleaches such as sodium perborate (e.g., monohydrate or tetrahydrate) may be used herein.

Another class of bleaching agents that can be used without limitation includes percarboxylic acid bleaching agents and salts thereof. Suitable examples of such bleaches include magnesium monoperoxyphthalate hexahydrate, magnesium m-chloroperbenzoate, magnesium 4-nonylamino-4-oxoperoxybutyrate and magnesium diperoxydodecanedioate. These bleaches are disclosed in U.S. patent No. US4483781 to Hartman, issued on 20/11/1984, U.S. patent application 740446 to Burns et al, issued on 3/6/1985, european patent application 0133354 to Banks et al, issued on 20/2/1985, and U.S. patent No. US4412934 to Chung et al, issued on 1/11/1983. Highly preferred bleaching agents also include 6-nonylamino-6-oxo-peroxyhexanoic acid as described in U.S. patent No. 4,34551 to Burns et al, 6.1.7.

Peroxygen bleaches may also be used. Suitable peroxy bleach compounds include sodium carbonate peroxyhydrate and its equivalent, "percarbonate" bleaches, sodium pyrophosphate peroxyhydrate, urea peroxyhydrate, and sodium peroxide. Persulfate bleach (e.g., OXONE, commercially produced by DuPont) can also be used.

Preferred percarbonate bleach compositions comprise dry particles having an average particle size in the range of from about 500 to about 1000 microns, no more than about 10% by weight of said particles being less than about 200 microns and no more than about 10% by weight of said particles being greater than about 1250 microns. The percarbonate may optionally be coated with a silicate, borate or water-soluble surfactant. Percarbonate is available from various suppliers such as FMC, Solvay and Tokai Denka.

Mixtures of bleaching agents may also be used.

Peroxygen bleaches, perborates, percarbonates, etc., are preferably used in combination with bleach activators, which result in the in situ generation of peroxyacids corresponding to the bleach activators in aqueous solution (i.e., during the wash). Various non-limiting examples of activators are disclosed in U.S. patent No. 4915854, and U.S. patent No. 4412934, issued to Mao et al at 4/10 1990. Nonoyloxybenzene sulfonate (NOBS) and Tetraacetylethylenediamine (TAED) activators are typical activators, and mixtures thereof may also be used. Other typical bleaching agents and activators useful herein are also described in US 4634551.

Highly preferred amido-derived bleach activators are those of the formula:

R¹N(R⁵)C(O)R²c (O) L or R¹C(O)N(R⁵)R²C(O)L

Wherein R is¹Is an alkyl group containing from about 6 to about 12 carbon atoms, R²Is an alkylene radical having from 1 to about 6 carbon atoms, R⁵Is H or an alkyl, aryl, or alkaryl group containing from about 1 to about 10 carbon atoms, and L is any suitable leaving group. A leaving group is any group that is displaced from the bleach activator as a result of nucleophilic attack of the perhydrolysis (perhydrolysis) anion on the bleach activator. A preferred leaving group is benzenesulfonate.

Preferred examples of bleach activators of the above formula include (6-octanoylamino-hexanoyl) oxybenzene-sulfonate, (6-nonanoylamino hexanoyl) oxybenzene-sulfonate, (6-decanoylamino-hexanoyl) oxybenzene-sulfonate, and mixtures thereof, as described in U.S. patent No. 4634551, which is incorporated herein by reference.

Another class of bleach activators includes the benzoxazines disclosed in U.S. Pat. No. 4,4966723 to Hodge et al, granted at 30.10.1990 (which is incorporated herein by reference). Highly preferred activators of the benzoxazine class are:

another class of preferred bleach activators include acyl lactam activators, especially acyl caprolactams and acyl valerolactams of the formula:

wherein R is⁶Is H or an alkyl, aryl, alkoxyaryl, or alkylaryl group having from 1 to about 12 carbon atoms. Highly preferred lactam activators include benzoyl caprolactam, octanoyl caprolactam, 3, 5, 5-trimethylhexanoyl caprolactam, nonanoyl caprolactam, decanoyl caprolactamAcylcaprolactam, undecenoyl caprolactam, benzoyl valerolactam, octanoyl valerolactam, decanoyl valerolactam, undecenoyl valerolactam, nonanoyl valerolactam, 3, 5, 5-trimethylhexanoyl valerolactam and mixtures thereof. See also U.S. Pat. No. 4,45784 to Sanderson, issued on 8/10/1985, which is incorporated herein by reference, and which discloses acyl caprolactams, including benzoyl caprolactam, which are adsorbed into sodium perborate.

Those bleaching agents other than oxygen bleaching agents are also well known in the art and may be used in the present invention. One particularly preferred class of non-oxygen bleaching agents includes photosensitizing bleaching agents such as sulfonated zinc and/or aluminum phthalocyanines. See US4033718 issued to Ho1combe et al on 7/5 of 1977. If desired, detergent compositions will generally contain from about 0.025% to about 1.25% by weight of such bleaching agents, especially zinc phthalocyanine sulfonates.

If desired, the bleaching compound may be catalyzed by a manganese compound. Such compounds are well known in the art and include, for example, manganese-based catalysts as disclosed in US patents 5246621, US5244594, US5194416, US5114606 and european patent application publications EP549271Al, EP549272a1, EP544440a2 and EP544490a 1; preferred examples of these catalysts include Mn^IV ₂(u-O)₃(1, 4, 7-trimethyl-1, 4, 7-triazacyclononane)₂(PF₆)₂，Mn^III ₂(u-O)₁(u-OAc)₂(1, 4, 7-trimethyl-1, 4, 7-triazacyclononane)₂(ClO₄)₂，Mn^IV ₄(u-O)₆(1, 4, 7-triazacyclononane)₄(ClO₄)₄，Mn^IIIMn^IV ₄(u-O)₁(u-OAc)₂(1, 4, 7-trimethyl-1, 4, 7-triazacyclononane)₂(ClO₄)₃，Mn^IV(1, 4, 7-trimethyl-1, 4, 7-triazacyclononane) - (OCH₃)₃(PF₆) And mixtures thereof. Other metal-containing bleach catalysts include those disclosed in US4430243 and US 5114611. The use of manganese with various complex ligands for improving bleaching is also reported in the following U.S. patents: 4728455, 5284944, 5246612, 5256779, 5280117, 5274147, 5153161 and 5227084.

In practice, without limitation, the compositions and methods of the present invention may be adjusted to provide at least about one per million of active bleach catalyst in the aqueous wash solution, preferably from about 0.1ppm to about 700ppm, more preferably from about 1ppm to about 500ppm of catalyst species in the wash solution.

Enzyme

Enzymes may be included in the formulations of the present invention for a variety of purposes in the laundering of fabrics, including, for example, the removal of protein, carbohydrate or triglyceride containing stains, and for the inhibition of dye migration by shedding, and for fabric restoration. Enzymes to be incorporated include proteases, amylases, lipases, cellulases, peroxidases, and mixtures thereof. Other types of enzymes may also be included. They may be derived from any suitable source, for example plant, animal, bacterial, mould and yeast sources. However, their selection is governed by several factors, such as pH-activity and/or optimum stability, thermostability, and stability towards active detergents, builders, etc. In this respect, bacterial or fungal enzymes are preferred, such as bacterial amylases and proteases, and fungal cellulases.

Typically, a sufficient amount of enzyme is incorporated to provide up to about 5 mg by weight, more typically about 0.01 mg to about 3 mg of active enzyme per gram of composition. In other words, the compositions of the present invention generally comprise from about 0.001% to about 5%, preferably from 0.01% to 1%, by weight of the commercial enzyme preparation. Proteases are typically present in such commercial preparations at levels sufficient to provide 0.005 to 0.1Anson Units (AU) of activity per gram of composition.

Examples of suitable proteases are subtilisins, which are obtained from particular strains of Bacillus subtilis and Bacillus licheniformis. Another suitable protease is obtained from a strain of Bacillus having maximum activity in the pH range 8-12, which has been developed and sold by the company Novo Industries A/S under the registered trade name ESPERASE. The preparation of this and similar enzymes is described in British patent Specification 1243784 of the company Novo. Commercially available proteolytic enzymes suitable for removal of proteinaceous soils include those sold under the trade names ALCALASE and SAVINASE by Novo Industries A/S (Denmark) and MAXATASE by International Bio-Synthesis, Inc. (the Netherlands). Other proteases include protease A (see European patent application 130756 published on 9.1.1985); protease B (see European patent application No. 87303761.8, filed on 28.4.1987 and European patent application No. 130756, published on 9.1.1985 by Bott et al).

Amylases include, for example, α -amylase as described in British patent specification 1296839(Novo), RAPIDASE from International Bio-Synthesis, Inc., and TERMAMYL from Novo Industries.

Cellulases useful in the present invention include bacterial and fungal cellulases. Preferably, they have an optimum pH of 5 to 9.5. Suitable cellulases are disclosed in U.S. patent No. 4435307 issued on 3/6/1984 to Barbesgoard et al, which discloses cellulase enzymes 212 produced by Humicola insolens or Humicola strains (Humicola strain) DSM1800 or by molds belonging to the genus aeromonas, and cellulase enzymes extracted from the hepatopancreas of marine mollusks (Dolabella Auricula Solander). Suitable cellulases are also disclosed in GB-A-2075028; GB-A-2095275 and DE-OS-2247832. CAREZYME (Novo) is particularly useful.

Suitable lipases which may be used in detergents include those produced by microorganisms of the Pseudomonas family, such as Pseudomonas stutzeri ATCC 19.154, disclosed in British patent 1372034. See also the lipase of Japanese patent application 5320487, published for public inspection on 24.2.1978. This lipase is commercially available from Amano pharmaceutical Co.Ltd. Nagoya, Japan under the trade name Lipase P "Amano", hereinafter referred to as "Amano-P". Other commercially available lipases include Amano-CES, a lipase derived from Chromobacterium viscosum, e.g., Chromobacterium viscosum NRRLB 3673, available from Toyo Jozo Co., Tagata, Japan; there are also the Chromobacterium viscosum lipases from Disoynth, U.S. and Netherlands, and the lipases from Burkholderia gladioli (Pseudomonas gladioli). Lipase derived from Humicola lanuginosa and commercially available from Novo (see also EP0341947) is a preferred lipase for use herein.

Peroxidases are used in combination with oxygen sources, e.g., percarbonates, perborates, persulfates, hydrogen peroxide, etc., for "solution bleaching," i.e., to prevent dyes or pigments that are released from a substrate during a washing operation from migrating to other substrates in the wash solution. Peroxidases are known in the art and include, for example, horseradish peroxidase, ligninase, and haloperoxidase such as chloro-or bromo-peroxidase. Detergent compositions containing peroxidase are disclosed in, for example, PCT International application WO89/099813 to O.Kirk, published 10/19 1989, assigned to Novo Industries A/S.

Various enzymatic materials and methods for their incorporation into synthetic detergent compositions are also disclosed in U.S. patent No. US3553139 to McCarty et al, issued on 5.1.1971. Enzymes are also disclosed in U.S. Pat. No. 4,18,1978 to P1ace et al, U.S. Pat. No. 4,1457 and U.S. Pat. No. 3,26,1985 to Hughes, U.S. Pat. No. 4507219. Enzymatic materials for liquid detergent formulations and methods for their incorporation into these formulations are disclosed in US4261868 to Hora et al, issued 4/14 in 1981. Enzymes used in detergents can be stabilized using a variety of techniques. Techniques for stabilizing enzymes are disclosed and exemplified in U.S. Pat. No. US3600319 issued to Gedge et al, 8/17 1971, and in European patent application publication No. 0199405, application No. 86200586.5 to Venegas, 10/29 1986. Enzyme stabilization systems are also described, for example, in US patent No. US 3519570.

Other components commonly used in detergent compositions and which may be incorporated into detergent tablets include sequestrants, soil release agents, soil antiredeposition agents, dispersants, suds suppressors, fabric softeners, dye transfer inhibitors and perfumes.

It is advantageous to store the compounds disclosed above for use in products in a packaging system.

The packaging system may be made from a sheet of flexible material. Materials suitable for use as the flexible sheet include single layer, coextruded or laminated films. Such films may comprise various components, such as polyethylene, polypropylene, polystyrene, polyethylene terephthalate. Preferably, the packaging system consists of an MVTR of less than 1 g/day/m²Is a co-extruded film of polyethylene and bi-oriented polypropylene. The MVTR of the packaging system is preferably less than 10 g/day/m²More preferably less than 5 g/day/m²Even more preferably less than 1 g/day/m²Most preferably less than 0.5 g/day/m². The film (2) may have various thicknesses. The thickness should generally be in the range of 10-150. mu.m, preferably 15-120. mu.m, more preferably 20-l 00. mu.m, even more preferably 25-80 μm, most preferably 30-40 μm.

The packaging material preferably comprises a barrier layer, which is conventional in packaging materials, having a low oxygen transmission rate, typically below 300cm³/m²A day, preferably less than 150cm³/m²A day, more preferably less than 100cm³/m²A day, even more preferably less than 50cm³/m²A day, most preferably less than 10cm³/m²The day is. Typical materials having such barrier properties include biaxially oriented polypropylene, polyethylene terephthalate, nylon, poly (ethylene vinyl alcohol), or laminates comprising one of these, and SiO_x(silicon oxide), or a metal foil such as aluminum foil. Such packaging materials may have a favourable effect on the stability of the product, for example in storage.

The packaging method used, generally the one disclosed in WO92/20593, includes flow-packaging or lidding packaging. When using this method, a longitudinal seal, which may be a fin seal or a cover seal, is used, and then the first end of the packaging system is sealed with a first end seal, followed by a second end seal. The packaging system may comprise a resealing method as described in WO 92/20593. In particular, the use of twisting, cold sealing or gluing is particularly suitable. In fact, a cold seal or adhesive strip may be applied to the packaging system at a surface location proximate the second end of the packaging system such that the strip provides both an initial seal and a reseal to the packaging system. In this case, the adhesive strip or cold seal strip may correspond to an area having an adhesive surface, i.e. a surface that only adheres to another adhesive surface. This resealing approach may also include spacers that may inhibit undesirable sticking. Such separators are described in WO95/13225 published 5/18.1995. There may also be a plurality of spacers and a plurality of adhesive strips. The main requirement is that the communication between the outside and the inside of the package should be minimal even after the first opening of the packaging system. Cold seals, particularly cold seal grids, may be used, wherein cold seals are employed to facilitate opening of the packaging system.

Examples

Example 1

i) A detergent base powder of composition C was prepared as follows: in the mixing drum or spray drum, all the particulate materials of the base composition are mixed together, except for the binder spray system, the fluorescer or brightener and the zinc photobleach phthalocyanine sulfonate, to form a homogeneous particulate mixture. The particle mixture was then divided into two equal parts, one for the preparation of the white layer and the other for the preparation of the green layer. A whitening agent or fluorescent agent is sprayed together with a half of the adhesive to prepare a white layer material. The photobleach zinc phthalocyanine sulfonate is sprayed with the rest of the binder to give a green layer material. Then in Loedige KM600^®Wherein each layer is processed independently.

ii) use of Bonals^®The rotary press was used to load two batches of substrate into two separate pressure-fed tanks. In the pre-compression and pressing stages, the two layers are pressed together to form a two-layer tablet.

iii) in this particular embodiment, the square cross-section of the sheet has sides 45mm, a height of 24mm and a weight of 45 gr. The height of the green bottom layer corresponds to 50% of the total height of the sheet.

iv) the sheet was then coated with 2.5g of a coating made from 80% by weight of sebacic acid and 20% by weight of Nymcel (carboxymethyl cellulose (degree of substitution 3), supplied by Metsa-Serla).

v) the color of the white layer of the coated sheet is given by the following numerical value: a-2, b-10, and L-85.

vi) the color of the green layer of the coated sheet is given by the following values: a-9, b-3, and L-80.

It will be appreciated that the colour measurement of such square sheets is carried out using 4 sheets each placed side by side to form a square with 90mm sides, so that colour measurements can be carried out on 50mm diameter areas.

The following are examples of basic particulate material compositions used to prepare the laundry detergent tablets of the present invention, wherein the fluorescer or brightener is preferably concentrated in the first layer and the zinc phthalocyanine sulfonate is preferably concentrated in the other layers.

For example, any of these compositions may be used, with all of the whitening agent in one layer and the zinc phthalocyanine sulfonate in the other layer. Other ratios between layers may be used in accordance with the present invention. The sheet having a single layer and colored with zinc phthalocyanine sulfonate can also be provided using a composition in which zinc phthalocyanine sulfonate is sprayed into a substrate, preferably in combination with an adhesive.

	Composition A (% by weight)
		Anionic agglomerates l	21.45
Anionic agglomerates 2	13.00
		Cationic agglomerates	5.45
Layered silicate	10.8
		Sodium percarbonate	14.19
Bleach activator agglomerates	5.49
		Sodium carbonate	13.82
EDDS/sulfate particles	0.47
		Tetra sodium hydroxy ethane diphosphonate	0.73
Soil release agent polymers	0.33
		Fluorescent agent	0.18
Phthalocyanine sulfonic acid zinc salt	0.025
		Soap powder	1.40
Suds suppressor	1.87
		Citric acid	7.10
Protease enzyme	0.79
		Lipase enzyme	0.28
Cellulase enzymes	0.22
		Amylase	1.08
Adhesive sprayed onto system	1.325
		Total of	100.00

The anionic agglomerate 1 comprises 40% anionic surfactant, 27% zeolite and 33% carbonate.

The anionic agglomerate 2 comprises 40% anionic surfactant, 28% zeolite and 32% carbonate.

The cationic agglomerate comprises 20% cationic surfactant, 56% zeolite and 24% sulfate.

The layered silicate comprises 95% SKS6 and 5% silicate.

The bleach activator agglomerate comprises 81% TAED, 17% acrylic acid/maleic acid copolymer (acid form) and 2% water.

Ethylenediamine N, N-disuccinic acid sodium salt/sulfate particles comprised 58% ethylenediamine N, N-disuccinic acid sodium salt, 23% sulfate and 19% water.

The suds suppressor contained 11.5% silicone oil (from Dow Corning), 59% zeolite and 29.5% water.

The binder spray system comprised 50% Lutensit K-HD96 and 50% PEG (polyethylene glycol).

	Composition B (% by weight)
		Anionic agglomerates 1	21.45
Anionic agglomerates 2	13.00
		Cationic agglomerates	5.45
Layered silicate	10.8
		Sodium percarbonate	14.19
Bleach activator agglomerates	5.49
		Sodium carbonate	12.645
EDDS/sulfate particles	0.47
		Tetra sodium hydroxy ethane diphosphonate	0.73
Soil release agent polymers	0.33
		Fluorescent agent	0.18
Phthalocyanine sulfonic acid zinc salt	0.025
		Soap powder	1.40
Suds suppressor	1.87
		Citric acid	7.10
Protease enzyme	0.79
		Lipase enzyme	0.28
Cellulase enzymes	0.22
		Amylase	1.08
Adhesive sprayed onto system	2.5
		Total of	100.00

The anionic agglomerate 1 comprises 40% anionic surfactant, 27% zeolite and 33% carbonate.

The anionic agglomerate 2 comprises 40% anionic surfactant, 28% zeolite and 32% carbonate.

The cationic agglomerate comprises 20% cationic surfactant, 56% zeolite and 24% sulfate.

The layered silicate comprises 95% SKS6 and 5% silicate.

The bleach activator agglomerate comprises 81% TAED, 17% acrylic acid/maleic acid copolymer (acid form) and 2% water.

Ethylenediamine N, N-disuccinic acid sodium salt/sulfate particles comprised 58% ethylenediamine N, N-disuccinic acid sodium salt, 23% sulfate and 19% water.

The suds suppressor contained 11.5% silicone oil (from Dow Corning), 59% zeolite and 29.5% water.

The binder spray system comprised 50% Lutensit K-HD96 and 50% PEG (polyethylene glycol).

	Composition C (%)
		Anionic agglomerates 1	9.1
Anionic agglomerates 2	22.5
		Nonionic agglomerates	9.1
Cationic agglomerates	4.6
		Layered silicate	9.7
Sodium percarbonate	12.2
		Bleach activator agglomerates	6.1
Sodium carbonate	7.67
		EDDS/sulfate particles	0.5
Tetra sodium hydroxy ethane diphosphonate	0.6
		Soil release agent polymers	0.3
Fluorescent agent	0.2
		Phthalocyanine sulfonic acid zinc salt	0.03
Soap powder	1.2
		Suds suppressor	2.8
Citric acid	5.5
		Protease enzyme	1
Lipase enzyme	0.35
		Cellulase enzymes	0.2
Amylase	1.1

Watch (continue)

Adhesive sprayed onto system	4.75
		Sprayed fragrance	0.5

The anionic agglomerate 1 comprises 40% anionic surfactant, 27% zeolite and 33% carbonate.

The anionic agglomerate 2 comprises 40% anionic surfactant, 28% zeolite and 32% carbonate.

The nonionic agglomerates comprise 26% nonionic surfactant, 6% lutenst K-HD96, 40% anhydrous sodium acetate, 20% carbonate and 8% zeolite.

The cationic agglomerate comprises 20% cationic surfactant, 56% zeolite and 24% sulfate.

The layered silicate comprises 95% SKS6 and 5% silicate.

The bleach activator agglomerate comprises 81% TAED, 17% acrylic acid/maleic acid copolymer (acid form) and 2% water.

Ethylenediamine N, N-disuccinic acid sodium salt/sulfate particles comprised 58% ethylenediamine N, N-disuccinic acid sodium salt, 23% sulfate and 19% water.

The suds suppressor contained 11.5% silicone oil (from Dow Corning), 59% zeolite and 29.5% water.

The binder spray system comprised 16% by weight of a polymer having the formula:

68% by weight of PEG4000 and 16% by weight of DIBS (sodium diisoalkylbenzene sulfonate or sodium toluene sulfonate).

	Composition D (%)
		Anionic agglomerates 1	32
Cationic agglomerates	5
		Layered silicate	11.5
Sodium percarbonate	16.2
		Bleach activator agglomerates	4.7
Sodium carbonate	3.76
		Sodium bicarbonate	2.0
Sodium sulfate	2.4
		EDDS/sulfate particles	0.5
Tetra sodium hydroxy ethane diphosphonate	0.8
		Soil release agent polymers	0.3
Fluorescent agent	0.1
		Phthalocyanine sulfonic acid zinc salt	0.02
Suds suppressor	2.1
		Citric acid	2
Protease enzyme	0.7
		Lipase enzyme	0.2
Cellulase enzymes	0.2
		Amylase	0.6
Perfume encapsulates	0.2
		Polymer particles	3
Sprayed fragrance	0.35
		Non-ionic system on spray	5.17
Zeolite	6.2

The anionic agglomerate 1 comprises 40% anionic surfactant, 27% zeolite and 33% carbonate.

The cationic agglomerate comprises 20% cationic surfactant, 56% zeolite and 24% sulfate.

The layered silicate comprises 95% SKS6 and 5% silicate.

The bleach activator agglomerate comprises 81% TAED, 17% acrylic acid/maleic acid copolymer (acid form) and 2% water.

Ethylenediamine N, N-disuccinic acid sodium salt/sulfate particles comprised 58% ethylenediamine N, N-disuccinic acid sodium salt, 23% sulfate and 19% water.

The suds suppressor contained 11.5% silicone oil (from Dow Corning), 59% zeolite and 29.5% water.

The perfume encapsulate comprised 50% perfume and 50% starch.

The polymer particles contained 36%, 54% zeolite and 10% water.

The non-ionic system on spray comprised 67% C12-C15AE5 (alcohol with an average of 5 ethoxy groups per molecule), 24% N-methylglucamide and 9% water.

Claims (10)

1. A detergent tablet comprising at least one coloured layer wherein the colour is produced by a component having a cleaning action.

2. A detergent tablet according to claim 1, wherein the tablet comprises at least two coloured layers and at least one other layer is white.

3. A detergent tablet according to claim 2, wherein the white layer comprises a greater amount of the brightener component than the other layer.

4. A detergent tablet according to claim 2, wherein the white layer does not contain any coloured component.

5. A detergent tablet according to claim 1, wherein the component having a cleaning action is a coloured photo-bleach.

6. A detergent tablet according to claim 1, wherein the detergent tablet is free of dyes.

7. A detergent tablet according to claim 1, wherein the tablet comprises at least two coloured layers and at least one further layer has a different colour.

8. A detergent tablet according to claim 1, wherein the tablet has a tensile strength of less than 100 kPa.

9. A detergent tablet according to claim 1, wherein the tablet further comprises a binder.

10. A process for the preparation of a tablet according to claim 1, wherein in a first step the ingredients having a cleaning action are mixed with a non-ionic carrier, sprayed onto the specific product in a second step, and the specific product is compressed into tablets in a third step.

Images