Surfactant thickened systems comprising microfibrous cellulose and methods of making same

[0001] Surfactant-based products, such as body cleansers, shampoos, dishwashing liquids, laundry detergents and automatic dishwasher detergents, are often thickened by using a high concentration of surfactants, by a combination of agents surfactants with synergistic effects on viscosity or by combining surfactants with small amounts of salts such as sodium salts. Such recipes result in high viscosity products that appear attractive and smooth, but their limitation is that they do not provide sufficiently low shear viscosity to allow suspension of particulate materials. Such particulate materials may include aesthetics (decorative beads, pearlescent agents, air bubbles, fragrance beads, etc.) or active ingredients (insoluble enzymes, encapsulated active substances such as moisturizing agents, zeolites, exfoliating agents (e.g. alpha hydroxy acids and / or glycolic acid or polyethylene beads), vitamins (e.g. vitamin E)) etc. or both.

[0002] Conventional thickeners and suspending agents such as xanthan gum, carboxymethyl cellulose (CMC), hydroxyethyl cellulose (HEC), hydroxypropyl methyl cellulose (HPMC) and various types of polyacrylates do not work well in surfactant thickened systems and often lead to loss of surfactant systems. transparency due to turbidity, gelation and / or phase separation or lack of sufficient suspending properties. For example, xanthan gum provides excellent suspending properties for body washing formulations with low surfactant concentration, but the rubber often loses its ability to suspend in systems thickened with a large amount of surfactant, usually resulting in a cloudy, irregular appearance, and a granular or lumpy texture. Cellulose products (CMC, HEC, HPMC, etc.), as other examples of conventional thickeners, give a slurry suspension and show significant restrictions in terms of compatibility of surfactants. Acrylate systems are widely used, however, such systems do not always achieve a sufficient level of clarity, they require high polymer concentrations and are not considered natural. Salts can often increase high shear viscosity in surfactant concentrated systems, but they do not provide long-term suspending ability.

[0003] There is currently a need in the consumer product industry to provide transparent surfactant thickened systems with suspended materials in particulate form as well as agents to facilitate suspension for systems with a high surfactant content where many alternative thickeners it will not work.

[0004] It has been found that microfibrous cellulose (MFC), of bacterial or other origin, can be used to form suspensions of particulate materials in surfactant-concentrated systems, as well as in preparations with a high concentration of surfactants. It has also been found that MFC can be used for this purpose with or without co-measures. When microfibrous cellulose of bacterial origin is used, the cell pellet can be removed to obtain transparent solutions at the concentrations typically used.

[0005] It turns out that microfibrous cellulose is not affected by the formation of surfactant micelles and a good suspension is maintained in such systems. A unique feature of microfibrous cellulose is its ability to function in such systems for a significant part due to the fact that it is dispersed rather than solubilized, due to which the desired properties of the suspension in preparations are obtained, which could otherwise show turbidity and / or precipitation, often observed using alternative solubilized polymers.

Brief Summary of the Invention [0006] Surfactant systems containing microfibrous cellulose have been described. "Surfactant Systems" are intended, but are not limited to, those concentrated by surfactant and high surfactant content. Microfiber cellulose (MFC) includes MFC produced by microbial fermentation or MFC produced by mechanical disruption / processing of cellulose fibers based on cereals, wood or cotton. When microfibrous cellulose of bacterial origin is used, the cell pellet can be removed to obtain transparent solutions when used at typical concentrations. According to the present invention, surfactants are used to obtain a very dense (very sticky) system at high shear rates with particulate material suspended therein by the use of microfibrous cellulose.

[0007] The concentration of surfactant in these systems ranges from about 5% to about 50% (w / w) of the active surfactant), the specific concentration being dependent on the product. Body cleansers usually contain about 5% to about 15% (weight) surfactant, dishwashing liquids usually contain about 20% to about 40% (weight) surfactant (with 40% being "ultra" concentrated product), and laundry detergents typically contain about 15% to about 50% (by weight) of the surfactant.

[0008] MFC is present in concentrations from about 0.05% to about 1.0%, but the concentration will depend on the desired product. For example, while a concentration of about 0.06% (w / w) MFC is preferred, when suspending small beads of alginate in a body wash, a concentration of about 0.075% is preferred for suspending air bubbles in a body cleaner. In addition, the MFC concentration will be appropriately controlled if a very transparent system is desired. Specifically, a very transparent body cleanser having a concentration of about 5% to about 15% (by weight active surfactant) can be obtained with an MFC concentration from about 0.055 to about 0.25% (weight active surfactant). MFC can be present at 0.06%, 0.075% or 0.09%. [0009] Suspended particle materials may include aesthetics (decorative beads, pearlescent agents, air bubbles, fragrance beads, etc.) or active ingredients (insoluble enzymes, encapsulated active substances such as moisturizers, zeolites, exfoliating agents (e.g. alpha hydroxy acids and / or glycolic acid or polyethylene beads), vitamins (e.g. vitamin E)) etc. or both. Other suitable particulate materials will be apparent to those skilled in the art.

[0010] Microfibrous cellulose blends are microfibrous cellulose products that contain co-agents. Two mixtures of MFC, xanthan and CMC in a ratio of 6: 3: 1, and MFC, guar and CMC in a ratio of 3: 1: 1 have been described. Such mixtures enable the preparation of MFC in the form of a dry product, 2

EP 2 486 912 B1 which can be "activated" by high shear or high intensity mixing in water or other water-based solutions. "Activation" occurs when MFC blends are added to water and co-agents / co-agents that facilitate processing are hydrated. After hydration of the co-agents / co-processing agents, high shear is usually required to effectively disperse the fibers of microfibrous cellulose to produce a three-dimensional functional network that exhibits a real yield point. It has been surprisingly found that the co-agent and / or co-agent facilitating processing, CMC, xanthan / xanthan gum and / or guar gum present in such microfibrous cellulose blends remain solubilized (when activated in water) in many formulations with a high content of surfactants despite their general absence compatibility / compatibility in systems with a high content of surfactants, most likely due to the low level / concentration of these polymers used in MFC preparations.

[0011] The invention further relates to methods for preparing the described surfactant systems. The invention further relates to a method for producing a surfactant system comprising combining microfibrous cellulose with water, followed by mixing, adding a surfactant, then mixing, adding particulate material, followed by mixing, the resulting system being transparent / transparent and the material in the form of particles are suspended in it.

Brief Description of Several Figures in the Drawing [0012] The above summary will become better understood when considered in conjunction with the detailed description of the invention and Figures 1-4.

Detailed description of the invention [0013] Body wash preparations demonstrating the characteristics of both surfactant concentration and suspension using a 0.125% MFC / xanthan / CMC (6: 3: 1) blend are described in Examples 1 and 2. Body cleansers show very good clarity and the ability to hang air bubbles and pearls.

[0014] Manual dishwashing liquids and liquid laundry detergents having a higher surfactant concentration than those found in body washes have also been described. Manual dishwashing liquids with alginate suspended therein are described in Example 3.

[0015] A liquid laundry detergent with fragrance beads suspended therein is described in Example 4. [0016] The wet form of microfibrous cellulose was used in Example 5 to prepare a system with a high amount of surfactant containing concentrated washing liquid with air bubbles suspended therein .

EXAMPLE 1 [0017] A liquid body wash with air bubbles was prepared. Fig. 1 shows the clarity and suspension characteristics of this system. The resulting body cleanser showed very thick

Rheology of the surfactant based on visual assessment, had the ability to suspend _® air bubbles, and a flow limit of about 3.4 Pa (measured with Brookfield rheometer^® Yield Rheometer).

[0018] Step A: Deionized water, 10% NaCl solution and Kathon^® CG was added to the small Oster mixer^®.

Microfibrous cellulose (MFC / xanthan / CMC 6: 3: 1 mix) was added to the water surface, after which _® Oster mixer blades turned on^® and the connection was mixed at the highest speed for 5 minutes ("liquefaction" speed).

[0019] Step B: the contents were transferred to a high beaker with blades for mixing paint with a capacity of 400 _® mL. Sodium lauryl ether sulfate (JEELATE) was added to the solution described in Step A^® ES-3), followed by mixing at a speed of about 1000 rpm for 5 minutes. Then added to the mix_® sodium cocamidopropyl betaine (JEETERIC^® CAB-LC) and mixed for an additional 5 minutes at 1000 rpm. Then fragrance was added.

[0020] Step C: Cocamide DEA was added to the solution described in Step B. Compaction occurred as DEA was added. Citric acid was then added as a 50% solution to reduce the pH to the desired level (in this case pH 5.5). The contents were removed from the mixer. Air entrained during mixing was stabilized by the presence of the MFC / xanthan / CMC 6: 3: 1 mix.

Table 1: Body cleanser for shower gel

<td>Stage process</td><td>Ingredient</td><td>% (by weight)</td><td>Grams</td>

<td></td><td></td><td></td><td></td>

<td>AND</td><td>Deionized water</td><td> 54,775</td><td> 219,10</td>

<td></td><td>Blend of microfibrous cellulose (blend MFC / xanthan / CMC 6: 3: 1)</td><td> 0,125</td><td> 0,50</td>

<td>AND</td><td>10% NaCl solution</td><td> 5,00</td><td> 20,00</td>

<td>AND</td><td>Kathon CG</td><td> 0,10</td><td> 0,40</td>

<td></td><td></td><td></td><td></td>

<td>B</td><td>Jeeteric® CAB-LC sodium cocamidopropyl betaine</td><td> 7,00</td><td> 28,00</td>

<td>B</td><td>Jeelate® ES-3 sodium lauryl ether sulfate</td><td> 25,00</td><td> 100,00</td>

<td>B</td><td>Fragrance</td><td> 1,00</td><td> 4,00</td>

<td></td><td></td><td></td><td></td>

<td>C</td><td>Cocoa DEA</td><td> 7,00</td><td> 28,00</td>

<td>C</td><td>Citric acid (50% solution)</td><td>How much is needed</td><td>How much is needed</td>

<td>Together</td><td></td><td> 100,00</td><td> 400,00</td>

EP 2 486 912 B1

EXAMPLE 2 [0021] A body wash was prepared as described in Example 1, but introducing a suspension of beads instead of air bubbles. Alginate beads were added at the end of stage C. A visual representation of this embodiment can be seen in Fig. 2.

EXAMPLE 3 [0022] Systems with high surfactant concentration were prepared using hand dishwashing liquids and laundry detergent. Alginate beads or vesicles were suspended in the solutions_® air. Palmolive Ultra dishwashing liquid^® diluted twice to form a "normal" concentration intravenous fluid. A concentrate containing 0.25% microfibrous cellulose blend (MFC / xanthan / CMC blend 6: 3: 1) in deionized water was first prepared. Concentrate_® prepared by mixing the solution in an Oster blender^® for "liquefying" (at the highest speed) for 5 minutes. The microfibrous cellulose blend was then diluted 1: 1 with Palmolive (R) (R) (R) detergent

Ultra^® or Dawn Ultra detergent^® (Palmolive^® contained 0.1% triclosan) using a painting mixing blade or propeller blade. Dishwashing liquid was added to the microfibrous cellulose solution while mixing. In both samples, Palmolive Ultra detergent^® and Dawn Ultra detergent^®, excellent clarity and suspension of air bubbles and / or alginate beads have been achieved. Microfibrous cellulose was diluted properly despite the relatively low shear of the paint or propeller mixing blade. The flow limit for these solutions was about 2.5 Pa. A visual representation can be seen in Fig. 3.

EXAMPLE 4 [0023] A high concentration surfactant system was prepared using concentrated fluid _® laundry. The All Small and Mighty detergent was used^® three times concentrated. " Mixture concentrate

0.25% microfibrous cellulose (MFC / xanthan / CMC blend 6: 3: 1) activated in distilled water _® using the Oster blender kit^® at the highest speed (liquefaction).

The mixing time was 5 minutes. The microfibrous cellulose solution was diluted 1: 1 with "All_®

Small and Mighty^® concentrated three times. " Very good clarity and suspension with a flow limit of 0.62 Pa were obtained for this dilution. The detergents were placed in an oven at 45 ° C to assess thermal stability and showed excellent stability without loss of clarity or suspension for 4 weeks of aging. The visual representation can be seen in Fig. 4.

Example 5 [0024] A high concentration surfactant system was prepared using a concentrated washing liquid using a wet weight variety of microfibrous cellulose. The All Small detergent was used_® and Mighty^® concentrated three times. "1.56% wet weight of microfibrous cellulose _® activated in distilled water using an Oster blender kit^® at the highest speed (liquefaction). The mixing time was 5 minutes. The activity (% solids) of this MFC wet weight form was about 16%, so that the concentration of activated MFC in the concentrate was about 0.25%. Solution 5

EP 2 486 912 B1 _® microfibrous cellulose was diluted 1: 1 with "All Small and Mighty."^® concentrated three times. A very good suspension was obtained for this dilution, reaching a flow limit of 13 Pa. The visual representation can be seen in Fig. 5.