Classifications

• • C—CHEMISTRY; METALLURGY
  • C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
  • C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
  • C11D17/00—Detergent materials or soaps characterised by their shape or physical properties
  • C11D17/06—Powder; Flakes; Free-flowing mixtures; Sheets
• • C—CHEMISTRY; METALLURGY
  • C11—ANIMAL OR VEGETABLE OILS, FATS, FATTY SUBSTANCES OR WAXES; FATTY ACIDS THEREFROM; DETERGENTS; CANDLES
  • C11D—DETERGENT COMPOSITIONS; USE OF SINGLE SUBSTANCES AS DETERGENTS; SOAP OR SOAP-MAKING; RESIN SOAPS; RECOVERY OF GLYCEROL
  • C11D17/00—Detergent materials or soaps characterised by their shape or physical properties
  • C11D17/0047—Detergents in the form of bars or tablets
  • C11D17/0065—Solid detergents containing builders
  • C11D17/0073—Tablets

Definitions

• This invention relates to cleaning compositions and, in particular, particulate cleaning compositions to be formed into moulded bodies for use in, for example, fabric washing, dishware washing, stain removal and water softening
• Detergent compositions in the form of tablets are widely described and are currently enjoying increasing popularity with consumers They are described, for example, in GB 0 91 1 204 (Unilever), US 3 953 350 (Kao), DE 19 637 606 (Henkel), EP 0 71 1 827 (Unilever) and WO 98/40463 (Henkel) Tablets for machine dishwashing applications are described in, for example, WO 96/28530 (P&G) Tabletted detergents and cleaning compositions have several advantages over powdered or liquid compositions they are easier to dispense and handle, do not require measuring to obtain the correct dose and, being compact, are more economical to store and transport
• Tablets of cleaning compositions are generally made by compression or compaction of a quantity of the composition in the form of particles
• Production of tablets which are sufficiently hard and strong to withstand storage and handling requires a relatively high pressure to be used in this compaction process It is then necessary that, despite this compaction, the tablets are able to disperse and dissolve rapidly when added to wash water
• the present invention seeks to provide a particulate cleaning composition in the form of a moulded body and which is relatively inexpensive to manufacture and sufficiently robust to withstand handling during production and packaging processes but readily breaks up and dissolves when contacted with an aqueous medium during the cleaning process for which it is intended without resulting in undue deposition on the substrate being cleaned
• a cleaning composition including disintegrant in the form of granules comprising a water insoluble inorganic material and a water-swellable agent which, in its anhydrous state, comprises no more than 20% of the combined weight of said inorganic material and said agent of the granular disintegrant, the granules being combined with the active ingredients of the cleaning composition in a compacted moulded body
• a granular composition suitable for use in a cleaning composition consists essentially of a water insoluble inorganic material and a water-swellable agent which, in its anhydrous state, comprises no more than 20% of the combined weight of said inorganic mate ⁇ al and said agent of the granular composition
• water insoluble we mean a compound with a water solubility of less than 5 grams, preferably less than 1 gram, per 100 grams water (at a temperature of 25°C)
• the water-swellable agent comprises, in its anhydrous state, no more than 15%, more preferably no more than 10%, of the combined weight of said inorganic material and said agent of the granular disintegrant
• the water- swellable agent comprises, in its anhydrous state, no more than 8%, e g 7 5% or less, of the combined weight of said inorganic material and said agent
• at least 1 % of the combined weight of the water-swellable agent and the inorganic material in the granules comprises water-swellable agent
• a feature of the invention is the relatively small amount of water-swellable agent that may be employed while securing satisfactory properties for the compacted cleaning composition Frequently, the amount of water-swellable agent in the cleaning composition is less than 2% by weight
• the amount is less than 1 % of the cleaning composition but, usually, at least 0 2% of the water-swellable agent is present in the cleaning composition
• the inorganic material no more than 15%, more preferably no more than 10%,
• the water-swellable agent preferably has an average primary particle size up to about 600 ⁇ m, but, conveniently, has an average primary particle size of no more than 200 ⁇ m, preferably no more than 100 ⁇ m, and a water swelling capacity of at least 5 ml/gram, preferably 10 ml/gram and more preferably 20 ml/gram as determined in the test described hereinafter
• the water-swellable agent comprises polymer, frequently a wholly or partially cross-linked polymer, e g natural cellulose, cross-linked cellulose, (sodium) carboxy- methyl cellulose, cross-linked sodium carboxymethyl cellulose, pre-gelatinised starch, cross linked starch, or cross linked polyvinyl pyrrolidone
• a wholly or partially cross-linked polymer e g natural cellulose, cross-linked cellulose, (sodium) carboxy- methyl cellulose, cross-linked sodium carboxymethyl cellulose, pre-gelatinised starch, cross linked starch, or cross linked polyvinyl pyrrolidone
• Aquasorb A500 ex Hercules
• Ac-Di-Sol ex FMC Corp
• the moulded body formed using the cleaning composition of the present invention may consist wholly of the cleaning composition or alternatively the moulded body may comprise a number of discrete portions, at least one of which comprises a cleaning composition in accordance with the invention
• the remaining portion or portions of the moulded body may be constituted by at least one other ingredient, usually one suitable for use in detergent and cleaning applications such as fabric washing, dishware washing, stain removal and water softening
• Cleaning compositions of the invention may also contain, as essential ingredients, one or more detergency builders (wholly or partly incorporated in the disintegrant granules), and/or one or more detergent-active compounds which may be chosen from soap and non-soap anionic, cationic, nonionic, amphote ⁇ c and zwitte ⁇ onic detergent-active compounds, and mixtures thereof and/or other conventional additives
• a further aspect of the invention comprises a process for the preparation of a cleaning composition comprising forming a granular disintegrant composition consisting essentially of a water in
• the preferred detergent-active compounds that can be used are soaps and synthetic non-soap anionic and nonionic compounds
• Anionic surfactants are well known to those skilled in the art. Examples include alkylbenzene sulphonates, particularly sodium linear alkylbenzene sulphonates having an alkyl chain length of C 8 - C 15 , primary and secondary alkyl sulphates, particularly sodium C 8 - C 15 primary alcohol sulphates, olefin sulphonates; alkane sulphonates; dialkyl sulphosuccmates; and fatty acid ester sulphonates
• Nonionic surfactants that may be used include the primary and secondary alcohol ethoxylates, and ethoxylates of este ⁇ fied fatty acids, especially the C 9 - C 15 primary and secondary alcohols ethoxylated with an average of from 3 to 20 moles of ethylene oxide per mole of alcohol.
• surfactant and the amount present, will depend on the intended use of the detergent composition. For example, for machine dishwashing a relatively low level of a low- foaming nonionic surfactant is generally preferred In fabric washing compositions, different surfactant systems may be chosen, as is well known by the skilled detergent formulator, for handwashing products and for machine washing products
• the total amount of surfactant present will of course depend on the intended end use and may be as low as 0 5% by weight of the total composition, for example, in a machine dishwashing composition, or as high as 60% by weight of the total composition, for example, in a composition for washing fabrics by hand
• an amount of from 5 to 40% by weight of the total composition is generally appropriate
• cleaning compositions of the invention will contain from 1 to 20% by weight of the disintegrant granules based on total weight of the composition Frequently the cleaning compositions will contain from 4 to 10 % by weight of the disintegrant granules
• a suitable type of cleaning composition suitable for use in most automatic fabric washing machines contains both anionic and nonionic surfactants
• Cleaning compositions according to the invention may also suitably contain a bleach system
• Machine dishwashing compositions may suitably contain a chlorine bleach
• fabric washing compositions may contain peroxy bleach compounds, for example, inorganic persalts or organic peroxyacids, which may be employed in conjunction with activators to improve bleaching action at low wash temperatures
• peroxy bleach compounds for example, inorganic persalts or organic peroxyacids
• detergent compositions of the invention include sodium silicate, fluorescers, antiredeposition agents, inorganic salts such as sodium sulphate, enzymes, lather control agents or lather boosters as appropriate, pigments, and perfumes This list is not intended to be exhaustive
• the granules of inorganic material and swelling agent may be prepared by any of the methods that will be known to those skilled in the art, e g by blending the dry ingredients in a mixer (such as a Pek mixer available from George Tweedy & Co of Preston - 28lb S.A Machine) and compacting on a roller compactor (Alexanderwerk WP50 - manufactured by Alexanderwerk AG, D 5630 Remscheid 1 , Germany)
• a mixer such as a Pek mixer available from George Tweedy & Co of Preston - 28lb S.A Machine
• a minimum of 2 kg of blended mate ⁇ al so prepared is compacted by feeding into an Alexanderwerk roller compactor, fitted with a sintered block vacuum deaeration system
• the roller pressure setting is selected according to the strength of granule desired, higher pressures leading to stronger granules.
• roller pressure is between 8 and 25 MPa and a typical roller pressure is 10 MPa
• the compacted material from the compactor is fed into a granulator, which forms part of the machine, and forced through a mesh and the resulting granules are then screened to the desired particle size range, e g an average particle size of 250 to 1500 ⁇ m, using standard laboratory sieves
• the particles have a size range of 500 to 1200 ⁇ m Tablet Production Tablets used in the Examples that follow were produced using a 45 mm diameter die set (stainless steel) in conjunction with a Universal Testing Machine Type No Z030 from Zwick GmbH, Ulm, Germany
• a known quantity, 40-45 grams, of the cleaning composition which comprised the compositions mentioned in the Examples below was placed in the die, the die plunger was inserted and the assembly was placed between the platens of the Zwick machine which was operated to apply a predetermined pressure to produce a tablet having a defined density and, in particular, a dimensionally stable and fracture resistant tablet Tablets thus produced
• Tablets with different densities were produced in order to determine the tablet disintegration and conductivity profiles Tablets prepared had densities in the range 1250-1450 kg/m 3 , which are typical values for commercial fabric washing tablets found in the Western European market in 1998-9 Determination of tablet disintegration profile
• the tablet disintegration profile provides an indication of the extent to which various tablets (e g different compositions, different densities) disintegrate under the defined conditions 4500 g of demineralised water at 20°C were added to a 5 litre vessel fitted with pH, conductivity and temperature probes and maintained at a constant temperature of 20°C by immersion in a water bath
• the tablets to be tested were inserted into a metal cage having the dimensions 9 cm x 4 7 cm x 2 7 cm and having 16 apertures (each about 2 mm square) per cm 2
• the metal cage was attached to the shaft of an overhead stirrer (Heidolph/Janke and Kunkel stirrer) to allow it and its contents to be rotated while immersed in the demineralised water Prior to testing, the empty cage was immersed in the demineralised water and rotated at 80 rpm for a short period of time until the temperature of the demineralised water as detected by the temperature probe had stabilised at 20 ⁇ 0 2°C At this time, the conductivity,
• the tablet conductivity profile provides an indication of the extent to which various tablets (e g different compositions, different densities) dissolve under the defined conditions
• Conductivity measurements were obtained from the conductivity probe mentioned in Method 1 above at the same time as the tablet disintegration was measured Measurements of conductivity and pH were taken, initially at 30 second intervals for ten minutes and thereafter at one minute intervals for a further 20 minutes or until the conductivity measurements were observed to have reached a plateau corresponding to substantially total dissolution of the soluble portion of the tablet, i e equilibration of the tablet with water This procedure was repeated for a number of tablets having different compositions and different densities
• the disintegrant granules comprised a water insoluble inorganic material, specifically a zeolite or a silica or a combination thereof, and a water-swellable agent
• granules consisting of Persil powder alone or comprising a water-swellable agent or a mixture of a water soluble material, specifically sodium silicate or sodium carbonate, and a water-swellable material were also prepared and tested
• Doucil A24 is a P-type zeolite sold by Crosfield Limited of Warrington, UK
• SD2255 is a silica also obtainable from Crosfield Limited
• Doucil 4A (Trade Mark) is a 4A zeolite obtainable from Crosfield Limited
• the sodium disilicate is obtainable from Crosfield Limited under the trade mark Pyramid 95
• the sodium carbonate is obtainable
• APS represents average particle size (d 50 ) as measured using a Malvern
• the granules coded G and H contain inorganic materials which are water soluble and as such are not within the scope of the present invention These particular Examples are included for comparative purposes
• Tablets 1A to 1 H contain 2% by weight of granules A to H respectively, the other 98% being formed from concentrated Persil original non-Biological detergent powder Tablet 1J was fabricated entirely from the same Persil powder Tablets 1K and 1L were prepared from the same Persil powder, but incorporated 0 2% and 2% by weight of Aquasorb A500 powder respectively
• Table 3 shows the level of disintegration and the conductivity obtained after 10 minutes immersion in water for these tablets using the experimental protocol described above in Method 1
• the conductivity measurements are representative of the degree of dissolution of the soluble ionic constituents of the Persil detergent powder, the higher the conductivity value the greater the degree of tablet dissolution
• the measurement of disintegration shows the level of undismtegrated residue retained in the 'cage' Thus a high value indicates a poorly disintegrating tablet TABLE 3
• Table 4 shows data for Tablets 2E, 2F equivalent to the data in Table 3
• These tablets which are similar to the tablets used in Example 1 but contain granules E and F respectively, incorporated into tablets at 4% by weight instead of 2%
• the test method for measuring disintegration was Method 1 Again, it is clear that, by increasing the weight of granule in the tablet at these lower levels of Aquasorb inclusion, the excellent disintegrating properties of the granules can be retained without the need to significantly increase the total weight of disintegrating polymer in the tablet (since 4% inclusion of granule F corresponds to 2% of granule D in terms of the total weight of Aquasorb introduced into the granule) TABLE 4
• Table 5 shows further data for disintegration/conductivity (using disintegration Method 1 ) for tablets containing various of the granules, again incorporated into the tablets at 2% by weight These tablets are identified as 3X, where the X is the letter corresponding to the granule identity in Table 2 In this case, the tablets have been prepared at a higher density (1350 ⁇ 10 kg/m 3 ) At this higher density, it is possible to discriminate between the performance of the different granules A to D From this data, it appears that the zeolite-containing granules are preferred over the silica-containing variant, with the granules prepared from Doucil A24 being the best performing disintegrating agents
• a number of tablets were prepared using a standard detergent base powder, similar to concentrated Persil powder, but without minor additives, such as perfume Tablets containing disintegrant granules as shown in Table 6 below were prepared at a nominal density of 1250 kg/m 3 with 5% by weight of granules in the final detergent composition
• the disintegrant granules used were all based on the zeolite P, Doucil A24, which consisted of 90% aluminosilicate and 10% water by weight
• Ac-D ⁇ -Sol is a croscarmellulose sodium available from FMC Corporation, Philadelphia USA
• Cellulose powder BFT is a granulated sulphite cellulose available from Vendico Chemical AB,
• Nat ⁇ onal 78-1551 is a pre-gelatinised starch available from National Starch & Chemical,
• Albocel FT40 is a fibrous natural cellulose available from J Rettenmaier & Sohne, Rosenberg,

Landscapes

• Chemical & Material Sciences (AREA)
• Life Sciences & Earth Sciences (AREA)
• Engineering & Computer Science (AREA)
• Chemical Kinetics & Catalysis (AREA)
• Oil, Petroleum & Natural Gas (AREA)
• Wood Science & Technology (AREA)
• Organic Chemistry (AREA)
• Detergent Compositions (AREA)

Applications Claiming Priority (3)

Publications (1)

Family

ID=10858865

Family Applications (1)

Country Status (12)

Family Cites Families (6)

• 1999
  • 1999-08-10 GB GBGB9918782.5A patent/GB9918782D0/en not_active Ceased
• 2000
  • 2000-07-24 PL PL00353233A patent/PL353233A1/xx unknown
  • 2000-07-24 AU AU60038/00A patent/AU6003800A/en not_active Abandoned
  • 2000-07-24 MX MXPA02001371A patent/MXPA02001371A/es not_active Application Discontinuation
  • 2000-07-24 BR BR0013037-0A patent/BR0013037A/pt not_active Application Discontinuation
  • 2000-07-24 WO PCT/GB2000/002785 patent/WO2001011000A1/en not_active Application Discontinuation
  • 2000-07-24 CA CA002380682A patent/CA2380682A1/en not_active Abandoned
  • 2000-07-24 EP EP00946163A patent/EP1203069A1/en not_active Withdrawn
  • 2000-07-24 CZ CZ2002484A patent/CZ2002484A3/cs unknown
  • 2000-07-28 AR ARP000103921A patent/AR024984A1/es unknown
• 2002
  • 2002-01-23 ZA ZA200200627A patent/ZA200200627B/xx unknown
  • 2002-02-08 NO NO20020642A patent/NO20020642L/no not_active Application Discontinuation

Non-Patent Citations (1)

Also Published As

Similar Documents

Legal Events