Effervescent handwash powder laundry detergent effective on tough stains

Abstract

The invention relates to a free-flowing powder laundry detergent suitable for hand washing, which has fast and high foaming action and is suitable for removing tough dirt and enzymatic stains from laundry. The present invention offers a powder laundry detergent suitable for hand washing that foams quickly without requiring the user to spend time and effort foaming the detergent. The effervescent handwash powder laundry detergent according to the present invention provides ease of use, superior performance and savings.

Description

[0001] EFFERVESCENT HANDWASH POWDER LAUNDRY DETERGENT EFFECTIVE ON TOUGH STAINS

[0002] TECHNICAL FIELD OF THE INVENTION

[0003] The present invention relates to a powder laundry detergent.

[0004] The invention relates to a handwash powder laundry detergent.

[0005] The handwash powder laundry detergent is effervescent. Its fast and high foam producing and superior stain removal performance ensures ease of use.

[0006] The improved foam durability, effective cleaning performance on tough stains and economic feasibility of the compositions claimed according to the present invention result in greater customer appeal.

[0007] BACKGROUND OF THE INVENTION

[0008] Washing clothes by hand is a common practice in some parts of the world for economic reasons, convenience, or both. In the formulation of detergents, foaming or dirt-removing properties are considered extremely important factors, such that a detergent that foams excessively is not an effective cleaning indicator in a washing machine, whereas a significant amount of foam is considered an effective cleaning indicator when hand washing the clothes. Consumer perception of the adequacy of the detergent dosage depends on the amount of foam produced by the detergent. It is therefore essential to develop a detergent composition that produces enough foam to satisfy the consumer, depending on the type of use.

[0009] Consumers adjust the dose of handwash laundry detergent based on the amount and intensity of foam, which increases the cost of the washing process. Therefore, the handwash laundry detergent composition will tend to be replaced by other products while offering increased and accelerated foam quantity and lower cost. The pH of a typical laundry detergent is quite high, around 11. In contrast, handwash laundry products are used with water at a temperature that the consumer's hand can withstand, and often provide cold water washing.

[0010] WO 1998 / 046716 relates to effervescent detergent compositions. WO 1998 / 046716 describes the effervescent composition and effervescent granules. However, this composition requires an additional preliminary step and contains percarbonate. The additional preliminary step required for creating the effervescent detergent described in WO 1998 / 046716 entails an extra cost. In addition, the composition containing percarbonate has disadvantages such as declining percarbonate activity over time, difficulties in storage due to gas formation, formulation stability issues, irritation to sensitive skin during hand washing, and cost.

[0011] Producing a detergent composition that provides foam levels with improved durability while maintaining cleaning efficacy during hand washing of white and / or colored fabrics at low washing temperatures has been challenging.

[0012] Therefore, there is a growing need and demand for a handwash powder composition with high foaming capacity and durability that can be used to remove tough stains and / or dirt, even in low temperature washes.

[0013] SUMMARY OF THE INVENTION

[0014] The present invention is a free-flowing handwash powder detergent effective on oxygen and mannanase sensitive stains, comprising surfactant, enzyme, basic effervescent agent and acidic effervescent agent.

[0015] The present invention comprises a surfactant in an amount ranging from 8% by wt. to 15% by wt., a basic effervescent agent in an amount ranging from 10% by wt. to 41% by wt., and an acidic effervescent agent in an amount ranging from 10% by wt. to 41% by wt.

[0016] By increasing the enzyme activity of a composition of sodium bicarbonate, citric acid and surfactants in effective ratios, the inventors have achieved an effective cleaning power.

[0017] The present invention has been found to exhibit superior stain removal performance on oxygen-sensitive and mannanase-sensitive stains by showing high foaming with water in the presence of an acid and a carbonate source together with a surfactant.

[0018] Unlike existing formulations, on the other hand, the invention provides an advantage in enhancing the effervescent effect through the effective use of surfactants. It is well known that the increased surfactant content has a negative effect on the effervescent effect. Surfactants act as binders in the effervescent structure and delay foaming.

[0019] The present invention provides the high pH cleaning efficacy of conventional detergents at a lower pH without causing irritation or skin sensitization on the hands. The low pH composition of the present invention has a positive effect on preventing color loss of the laundry upon repeated washing.

[0020] The effervescent structure of the present invention ensures that no residue is formed after washing.

[0021] Additionally, the stain removal results of the present invention without the use of percarbonate and TEAD (tetraacetylethylenediamine) were found to be highly effective compared to other detergents.

[0022] The advantage of the present invention is that, due to its percarbonate-free composition, the performance of removing oxygen- and mannanase-sensitive stains is achieved even at low temperatures.

[0023] The advantage of the present invention is that the high foaming effervescent effect enhances the enzyme activity, thereby enabling the removal at low temperatures of tough dried stains such as those from processed foods, chocolate and sauces, puddings, ice cream, chocolate ice cream, mayonnaise, ketchup, salad dressings, tea, coffee, wine, cherries, cherry juice, beetroot, beetroot juice, etc.

[0024] As a further advantage of the present invention, it has been observed that the enzyme-enriched handwash powder laundry detergents known in the art do not cause the color fading problem caused by detergents, thus preserving the vibrancy of the colors.

[0025] DESCRIPTION OF THE INVENTION The present invention relates to a high-foaming, free-flowing, effervescent handwash powder detergent effective on oxygen and mannanase sensitive stains.

[0026] The purpose of the invention is to provide a free-flowing handwash powder laundry detergent composition which is effective on oxygen and mannanase sensitive stains, provides easy washing due to its effervescent effect and high foam production, enhances enzyme activity and does not cause color fading and hardening of the laundry upon repeated laundering.

[0027] The composition of the present invention comprises elements which contribute to the formation of the effervescent effect.

[0028] The effervescent effect is created by an acid and a carbonate source.

[0029] According to the present invention, the acid source is organic acid.

[0030] The acids are preferably mono-, bi- or tri-protonic acids.

[0031] Among such preferred acids are mono- or polycarboxylic acids, preferably citric acid, adipic acid, glutaric acid, citramalic acid, tartaric acid, maleic acid, malic acid, succinic acid, malonic acid.

[0032] Such acids are preferably used in the form of acid or acid salt and their anhydrous forms or combinations thereof may be preferred.

[0033] The most preferred one is citric acid.

[0034] According to the present invention, the composition comprises the acidic effervescent agent in an amount ranging from 10% to 45%, preferably from 10% to 43%, and more preferably from 10% to 41% by weight of the total composition.

[0035] According to the present invention, the carbonate source reacts with the acid source in the presence of water to produce carbon dioxide gas.

[0036] The carbonate source is preferably selected from alkaline and / or alkaline earth metal salts of carbonate, bicarbonate and the combinations thereof.

[0037] A more preferably selected carbonate source is sodium bicarbonate.

[0038] According to the present invention, the composition contains the basic effervescent agent or mixtures of this carbonate source in an amount ranging from 10% to 45% by weight of the total composition, preferably from 10% to 43%, and more preferably from 10% to 41%. Enzyme: The present inventive composition comprises an enzyme or a combination of enzymes. Preferably, the composition of the invention comprises a combination of mannanase, cellulase and lipase.

[0039] The present invention comprises mannanase, lipase, and cellulase enzymes in an amount ranging from 0% to 1% by weight of the total composition, and more preferably between 0.01% and 1%.

[0040] The composition of the present invention comprises surfactants. These surfactants are preferably anionic and non-ionic surfactants. These anionic and non-ionic surfactants contribute to the cleaning performance.

[0041] The preferred anionic surfactant is linear alkyl benzene sulfonic acid sodium salt (LABSA.Na).

[0042] LABSA.Na is produced by sulfonation of linear alkyl benzene (LAB) producing linear alkyl benzene sulfonic acid (LABSA), which is then neutralized with sodium hydroxide to produce LABSA.Na. The LAB used in the production of LABSA.Na may be of HF and / or Detal type.

[0043] LAB used in the production of LABSA.Na contains a maximum of 1% Cg-phenyl, 8-18% Cio-phenyl, 26-38% Cn-phenyl, 26-38% Ch-phenyl, 15-27% Ci3-phenyl, and a maximum of 1% Ci4-phenyl by total weight of LAB. The 2-phenyl isomer content of LAB may range from 15-22% by weight for HF type and from 25-35% by weight for Detal type.

[0044] The resulting LABSA.Na contains at least 96% solid matter by weight and exhibits a similar carbon distribution to the LAB raw material.

[0045] LABSA.Na is added to detergent compositions before the spray-drying process (i.e., it is present in the slurry to be spray-dried).

[0046] The preferred nonionic surfactant group consists of ethoxylated alcohols.

[0047] Ethoxylated alcohols may be selected from C12-C18 fatty alcohol ethoxylates with 5-9 EO, C13-C15 oxo alcohol ethoxylates with 5-9 EO, and C9-C11 oxo alcohol ethoxylates with 6-10 EO.

[0048] According to the present invention, the preferred nonionic surfactant can be represented by the following formula (a): Ri-O-(CH2-CH2-O)mH

[0049] (a) where predominantly unbranched (linear) C13-C15 oxo alcohol and m=3 - 11. A more preferred non-ionic surfactant of the present invention is oxo alcohol ethoxylate, wherein the number of ethoxyl groups (m) in formula (a) is 5 to 7.

[0050] The non-ionic surfactant is added to the compositions by a post-addition, which is created after spray drying and cooling to lower temperatures where the non-ionic surfactants are not adversely affected.

[0051] Filler: The present invention contains a filler material constituting between 20% and 45% by weight of the total composition. Where appropriate, the filler may be selected from sulfate salts, sodium acetate or sodium chloride or combinations thereof. The preferred main filler is sodium sulfate. The present detergent compositions also preferably include sodium chloride up to 5.5% by weight of the total composition. Fillers are added to detergent compositions prior to spray drying (i.e. they are present in the spray-dried slurry). Sodium sulphate, the main filler, helps to keep the effervescent detergent dry thanks to its moisture-absorbing properties and helps to reveal its effervescent properties during use.

[0052] In one embodiment according to the present invention, it further comprises zeolite up to 5% by weight of the total composition.

[0053] Optical brightener: The detergent compositions of the present invention may preferably comprise optical brighteners of less than 1.0%, more preferably up to 0.5%, by weight of the total composition. Optical brighteners may be selected from carboxylics such as distyrylbenzenes, distyrylbiphenyls and divinylstilbenes, triazinylaminostilbenes, stilbenyl-2H-triazoles such as stilbenyl-2H-naphthol[l,2- d]triazoles and bis(l,2,3-triazol-2-yl)stilbenes, benzoxazoles such as stilbenyl benzoxazoles and bis(benzoxazoles), furans, benzofurans and benzimidazoles such as bis(benzo[b]furan-2-yl)biphenyls and cationic benzimidazoles, l,3-diphenyl-2- pyrazolines, coumarins, naphthalimides, l,3,5-triazin-2-yl derivatives, methinesyanines, and dibenzothiphen-5,5-dioxide. The optical brighteners preferably used are diphenylethylene triazine and 4,4'-bis(2-sodium sulfonate stryl)biphenyl.

[0054] Sodium silicate added to detergent compositions may be represented by the following formula (b): mNaiO nSiOi

[0055] (b) where the ratio n / m is referred to as the modulus of sodium silicate. The preferred amount of sodium silicate in the present detergent compositions is preferably up to 3%. The detergent compositions are supplemented with sodium silicate before spray drying (i.e. it is present in the spray-dried slurry).

[0056] Perfume: Perfume oils and / or encapsulated perfumes may preferably be added to detergent compositions in the range of 0% to 1% by weight.

[0057] METHOD FOR PREPARING DETERGENT COMPOSITION

[0058] Labsa, sodium silicate, optical brightener, sodium sulfate and water are mixed into a slurry and transported at high pressure to a tower. Inside the tower, it is sprayed, dried at high temperature and thus granulated. The prepared powder is supplemented with zeolite, enzymes (mannanase, lipase, cellulase), red sodium chloride, sodium bicarbonate and citric acid and then non-ionic surfactant and perfume are sprayed on it. The mixture prepared as such is stirred in a rotary horizontal mixer and homogenized.

[0059] The invention will be explained through examples, including but not limited to those provided below.

[0060] EXAMPLES

[0061]

[0062] Example 9 represents the composition according to the present invention.

[0063] Cl: Comparative example 1 (commercially-available effervescent additive-free handwash laundry detergent)

[0064] FOAMING PERFORMANCE

[0065] The foaming measurements for the effervescent handwash powder detergent were conducted using a 250ml glass graduated cylinder. The operating temperature was 45°C and the water hardness was 45°F. The samples were weighed on a precision balance (2 grams), and each formulation was measured with at least 5 repetitions. In the graduated cylinder, 200 ml of water was measured under specified conditions, and the weighed samples were carefully poured. After the samples were poured, the rise of the foam was monitored, and comparisons among the formulations were made by reading the graduated cylinder height at the moment the foaming ceased.

[0066] With regard to the foam heights, the optimum value was observed to be achieved with the composition of Example 9 of the present invention when the cost and stain removal performance were also taken into consideration.

[0067] STAIN REMOVING PERFORMANCE

[0068] A stain washing process was performed in the laboratory using EMPA and CFT standard stains using a tergotometer device. Stain washing conditions included 30 minutes, 40°C water temperature, 45°F water hardness, 90 rpm rotation speed and 4 repetitions. The washed fabrics were dried in a clean environment away from daylight, and subsequently, the dY (luminance C) values were measured using a spectrophotometer device. The dY value represents the luminance C difference between the original standard fabric and the washed fabric. The higher the value, the more the color of the washed fabric is considered to be different from the color of the original fabric, i.e. the lighter the color.

[0069] The foam content of exemplary formulations 1 and 2 appears to be high, but both the amount of acid source used to achieve the effervescent effect is too costly and the stain removal results are insufficient. The formulation of Example 3 provides the desired amount of foam, but the stain removal performance is insufficient due to the high pH of the formulation.

[0070] The foam content of exemplary formulations 4, 5 and 8 remains insufficient.

[0071] A comparison of Examples 7, 8, 9 and Cl showed that although the enzyme was reduced in Example 9, the effervescent effect increased the potency of the enzyme and ensured safe cleaning.

[0072] When the washing results of the examples were comparatively evaluated in terms of cost, stain performance, and processability, it was observed that exemplary formulation 9 exhibited better stain removal performance on oxygen-sensitive and mannanase- sensitive stains compared to both the comparative example and other exemplary formulations. This effect is thought to be due to the contribution of the effervescent effect to enzyme activity.

[0073] Textile Color Fastness The change in color (fading) of a fabric sample, evaluated in accordance with the AISE Color Protection Test method based on the TS 423-5 EN ISO 105-A05 standard, is calculated by comparing it with an untreated reference of the same characteristics, using an instrumental method (device-assisted) and converting the measurements obtained from the device into scale fastness values. The colors of the fabrics are classified as close and far from the reference example. The fabrics were subjected to evaluation using the Konica Minolta CM-3600d Spectrophotometer following 20 consecutive wash cycles (without intermediate drying) performed at 30°C for 30 minutes under a program with 900 rpm, 45 Fr water hardness, and 100 grams of detergent, followed by in-line drying.

[0074] 9: Exemplary composition of the present invention

[0075] *K 1: enzyme containing, handwash powder detergent

[0076] **K 2: enzyme containing, handwash powder detergent

[0077] It has been observed that the exemplary formulation (9) of the present invention, when used to wash laundry, does not cause color fading and even enhances vibrancy compared to market-available detergents containing enzymes (KI, K2).

Claims

CLAIMS1. A fast-foaming handwash powder laundry detergent composition effective on tough stains, characterized by comprising: a. between 8% and 20% by weight of a surfactant, b. between 0.01% and 1% by weight of a mixture of mannanase, cellulase, lipase enzymes, c. between 10% and 41% by weight of a basic effervescent agent d. between 10% and 41% by weight of an acidic effervescent agent.

2. A handwash powder laundry detergent according to Claim 1, characterized in that the equilibrium pH of the composition in a 1% by weight dilution in deionized water is between 5 and 7, preferably between 5.5 and 6.5.

3. A handwash powder laundry detergent according to Claim 1, characterized in that it comprises an anionic surfactant, a non-ionic surfactant, or a mixture thereof.

4. A handwash powder laundry detergent according to Claim 3, characterized in that the anionic surfactant is linear alkyl benzene sulfonic acid.

5. A detergent according to Claim 3, characterized in that the non-ionic surfactant is ethoxylated alcohols, preferably C12-C18 fatty alcohol ethoxylates with 5-9 EO, C13-C15 oxo alcohol ethoxylates with 5-9 EO, C9-C11 oxo alcohol ethoxylates with 6-10 EO, or a mixture thereof.

6. A handwash powder laundry detergent according to Claim 1, characterized in that the basic effervescent agent is sodium bicarbonate.

7. A handwash powder laundry detergent according to Claim 1, characterized in that it preferably contains sodium bicarbonate in an amount ranging from 15% to 30%.

8. A handwash powder laundry detergent according to Claim 1, characterized in that the acidic effervescent agent is citric acid anhydride.

9. A handwash powder laundry detergent according to Claim 1, characterized by preferably comprising citric acid anhydride in an amount preferably between 15% and 30%.

10. A handwash powder laundry detergent according to Claim 1, characterized in that it contains zeolite up to 5% by weight.

11. A handwash powder laundry detergent according to Claim 1, characterized in that it contains sodium chloride up to 5,5% by weight.

12. A handwash powder laundry detergent according to Claim 1, characterized in that it contains sodium silicate up to 3% by weight.

13. A handwash powder laundry detergent according to Claim 1, characterized in that it contains optical brightener up to 0,01% by weight.

14. A handwash powder laundry detergent according to Claim 1, characterized in that it contains sodium sulfate ranging from 20% to 45% by weight.

15. A method for producing a handwash powder laundry detergent according to Claim 1, characterized by comprising the following steps: a) Preparing a slurry by combining an anionic surfactant, silicate, optical brightener, sodium sulfate, and water, and transferring the slurry into a tower under high pressure; b) Spraying the slurry in the tower and drying it at high temperature to form granules; c) Adding zeolite, sodium chloride, enzymes, basic and acidic effervescent agents to the granules; d) Spraying a non-ionic surfactant and perfume onto the resulting mixture.

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