Method for stabilizing microcapsules in suspended fabric softener and application

Abstract

The invention discloses a method for stabilizing microcapsules in a suspended fabric softener and application. Dioctadecyl dimethyl ammonium chloride and cationic polyacrylamide are added into the fabric softener containing the cationic surfactant, so that the suspension stability and thermal stability of microcapsules in the fabric softener can be effectively improved. The invention also provides a fabric softener containing dioctadecyl dimethyl ammonium chloride, cationic polyacrylamide, a cationic surfactant and microcapsules. The fabric softener can effectively suspend the microcapsules with the mass fraction of 0.01-10%. Meanwhile, when the fabric softener is used and after the fabric softener is used, the microcapsules have better adsorbability and release performance on the surface of the fabric. The long-term stable dispersion of the microcapsule in the fabric softener containing the cationic surfactant is realized, and the microcapsule has a wide application prospect in washing care products.

Description

Technical Field

[0001] The invention relates to the technical field of household cleaning, and in particular to a method for stably suspending microcapsules in a fabric softener and an application thereof. Background Art

[0002] Microencapsulation technology is a technology that uses inorganic or organic materials to encapsulate solid, liquid or gaseous substances to form small particles with a core-shell structure and a diameter of 1 to 1000 μm. Microencapsulation products can better protect the effective and uniform existence of functional raw materials in systems with poor compatibility or incompatibility taboos, so that the functional substances can be released more efficiently and fully on the object being acted on. With the gradual increase in functional products and microencapsulated raw materials, microencapsulation technology has received more and more attention from the industry.

[0003] In the washing and care industry, the most widely used microcapsules are fragrance microcapsules. Manufacturers prepare fragrance microcapsules by encapsulating specific fragrance essential oils in microcapsules. The fragrance microcapsules are adsorbed on the surface of the fabric during the washing process, and then broken and released the fragrance for a long time due to external stimuli such as friction, pressure, and heat during wearing and use. At present, the content of fragrance microcapsules added to washing and care products is generally 0.2-0.4%. However, in the overseas market, some customers need to add 1-5% or even higher than 5% fragrance microcapsules to washing and care products. Therefore, how to suspend more fragrance microcapsules in the washing and care product system and ensure the efficient adsorption and release performance of fragrance microcapsules at the same time is crucial. In addition to the washing and care industry, microcapsule technology is also widely used in cosmetics, food, textiles, hygiene, medical care, public environmental protection and special industries, and these industries also have higher requirements for the suspension amount of microcapsules.

[0004] At present, microcapsule technology has the following main shortcomings: On the one hand, the traditional microcapsule encapsulation materials are divided into three categories: carbohydrates (such as dextrin, etc.), hydrophilic colloids and proteins. There are random dispersion distribution, weak action bonds (such as hydrogen bonds, dispersion forces, etc.) and viscous forces between these encapsulation materials and the objects being acted on. However, this kind of force is weak, which directly limits the enrichment and adsorption of microcapsules on the surface and inside of the objects being acted on, resulting in the waste and failure of the functional raw materials encapsulated by the microcapsules, and further limits the release performance and role of the functional raw materials.

[0005] On the other hand, during the use of microcapsules, due to the different capsule particle sizes (1 to 1000 μm) and the large difference in density with water, the microcapsules cannot be stably dispersed in water, thus precipitating or settling. The general solution is to use a suspension stabilizer to suspend and stabilize the microcapsules through yield force. However, it is difficult for existing suspension stabilizers to achieve this suspension effect in a cationic-based system, but cationic surfactants are often added to existing toiletries as softeners, bactericides, antistatic agents, conditioners, etc.

[0006] Therefore, it is of great significance to develop a method that can stably suspend microcapsules in systems containing cationic surfactants. Summary of the invention

[0007] In order to overcome the above defects and shortcomings in the prior art, the present invention provides a method for stably suspending microcapsules in a fabric softener and its application.

[0008] The first object of the present invention is to provide a composition for use in stabilizing the suspension of microcapsules in fabric softeners.

[0009] A second object of the present invention is to provide a method for stably suspending microcapsules in a fabric softener.

[0010] The third object of the present invention is to provide a fabric softener.

[0011] Therefore, the present invention claims the following:

[0012] The invention discloses an application of a composition to stabilize microcapsules of a suspended fabric softener, wherein the fabric softener contains a cationic surfactant and the composition contains dioctadecyl dimethyl ammonium chloride and a cationic polyacrylamide.

[0013] Preferably, the microcapsules contain functional substances such as essences, refining agents, essential oils, or are microcapsules with cooling, sterilization, sun protection, and medical functions.

[0014] More preferably, the wall material of the microcapsule is melamine resin, and the core material is essence or bactericide.

[0015] More preferably, the particle size of the microcapsule is 10 to 30 μm.

[0016] Preferably, the cationic polyacrylamide has a molecular weight range of 5000 to 1000000, an intrinsic viscosity range of 4 to 300 mL / G, and a cationic degree of 3 to 20%.

[0017] More preferably, the cationic polyacrylamide is FLOSOFT TM FS 222.

[0018] Preferably, the cationic surfactant is an ester-based quaternary ammonium salt.

[0019] More preferably, the ester-based quaternary ammonium salt is one or more of distallow ester hydroxyethyl ammonium methyl sulfate, dispalmityl ester hydroxyethyl ammonium methyl sulfate, disoleyl ester hydroxyethyl ammonium methyl sulfate and discocoyl ester hydroxyethyl ammonium methyl sulfate.

[0020] A method for stabilizing and suspending microcapsules in a fabric softener, comprising adding dioctadecyl dimethyl ammonium chloride and cationic polyacrylamide to the fabric softener;

[0021] The mass fraction of the dioctadecyl dimethyl ammonium chloride in the fabric softener is not less than 1%;

[0022] The mass fraction of the cationic polyacrylamide in the fabric softener is not less than 1%;

[0023] The fabric softener comprises a cationic surfactant.

[0024] Preferably, the cationic polyacrylamide has a molecular weight range of 5000 to 1000000, an intrinsic viscosity range of 4 to 300 mL / G, and a cationic degree of 3 to 20%.

[0025] More preferably, the cationic polyacrylamide is FLOSOFT TM FS 222.

[0026] Preferably, the cationic surfactant is an ester-based quaternary ammonium salt.

[0027] More preferably, the ester-based quaternary ammonium salt is one or more of distallow ester hydroxyethyl ammonium methyl sulfate, dispalmityl ester hydroxyethyl ammonium methyl sulfate, disoleyl ester hydroxyethyl ammonium methyl sulfate and discocoyl ester hydroxyethyl ammonium methyl sulfate.

[0028] Preferably, the microcapsules contain functional substances such as essences, refining agents, essential oils, or are microcapsules with cooling, sterilization, sun protection, and medical functions.

[0029] More preferably, the wall material of the microcapsule is melamine resin, and the core material is essence or bactericide.

[0030] More preferably, the particle size of the microcapsule is 10 to 30 μm.

[0031] A fabric softener, comprising a cationic surfactant, microcapsules, dioctadecyl dimethyl ammonium chloride and cationic polyacrylamide;

[0032] The mass fraction of the dioctadecyl dimethyl ammonium chloride in the fabric softener is not less than 1%;

[0033] The mass fraction of the cationic polyacrylamide in the fabric softener is not less than 1%.

[0034] Preferably, the cationic polyacrylamide has a molecular weight range of 5000 to 1000000, an intrinsic viscosity range of 4 to 300 mL / G, and a cationic degree of 3 to 20%.

[0035] Preferably, the cationic surfactant is an ester-based quaternary ammonium salt.

[0036] More preferably, the ester-based quaternary ammonium salt is one or more of distallow ester hydroxyethyl ammonium methyl sulfate, dispalmityl ester hydroxyethyl ammonium methyl sulfate, disoleyl ester hydroxyethyl ammonium methyl sulfate and discocoyl ester hydroxyethyl ammonium methyl sulfate.

[0037] Preferably, the microcapsules contain functional substances such as essences, refining agents, essential oils, or are microcapsules with cooling, sterilization, sun protection, and medical functions.

[0038] More preferably, the wall material of the microcapsule is melamine resin, and the core material is essence or bactericide.

[0039] More preferably, the particle size of the microcapsule is 10 to 30 μm.

[0040] The inventors have found in practice that, according to the conventional method of fabric softener, when an ester quaternary ammonium salt and a cationic polyacrylamide system are used, the addition of microcapsules will cause the microcapsules in the fabric softener to precipitate. Even if the mass fraction of the cationic polyacrylamide is adjusted to 1.0% to 3.0% and the consistency of the fabric softener is above 3000 MPa.s, an effective yield force cannot be generated to suspend and stabilize the microcapsules.

[0041] However, the inventors have found in a large number of experiments that if a mass fraction of not less than 1% of dioctadecyl dimethyl ammonium chloride is added to the system, regardless of the amount of ester quaternary ammonium salt present, under the condition that the mass fraction of cationic polyacrylamide is not less than 1%, the fabric softener can effectively suspend microcapsules in the range of 0.1 to 10% and has excellent centrifugal stability and thermal stability.

[0042] Since N +The adsorption of the positively charged end and the carbon-hydrogen of the microcapsule encapsulating material obtains an extended (covered) positively charged large micelle, which produces a repulsive effect because they are all positively charged, thereby obtaining a stable state. The octadecyl end of dioctadecyl dimethyl ammonium chloride is large in volume and poorly water-soluble, and then carries the microcapsule micelle to produce mutual repulsion. This is the repulsive property produced by the steric hindrance effect, thereby enhancing stability. The carbon group in the microcapsule encapsulating material forms a hydrogen bond with the long-chain propylene (H) of cationic polyacrylamide, thereby relying on the expansion and cross-linking of the long-chain spatial structure of cationic polyacrylamide to produce a locking, dispersing and stabilizing effect on the microcapsule. Based on the above three effects, the microcapsules can be stably suspended in the cationic surfactant system, and the resulting fabric softener has excellent stability.

[0043] The present invention also provides a method for preparing a fabric softener, comprising the following steps:

[0044] S1. Add the microcapsules into water and homogenize at 500-1500 r / min;

[0045] S2. Add dioctadecyl dimethyl ammonium chloride and ester quaternary ammonium salt and stir evenly at 65 to 75 ° C;

[0046] S3. Add cationic polyacrylamide, disperse it evenly, and then add the remaining material to obtain the product.

[0047] Compared with the prior art, the present invention has the following beneficial effects:

[0048] The present invention discloses a method for stably suspending microcapsules in a fabric softener and its application. The present invention adds dioctadecyl dimethyl ammonium chloride and cationic polyacrylamide to a fabric softener containing a cationic surfactant, which can effectively improve the suspension stability and thermal stability of the microcapsules in the fabric softener. The present invention also provides a fabric softener comprising dioctadecyl dimethyl ammonium chloride, cationic polyacrylamide, a cationic surfactant and microcapsules, and the fabric softener can effectively suspend microcapsules with a mass fraction of 0.01 to 10%. At the same time, during and after use of the fabric softener, the microcapsules have good adsorption and release properties on the fabric surface. The present invention realizes long-term stable dispersion of microcapsules in a fabric softener containing a cationic surfactant, and has broad application prospects in washing products and other industries. DETAILED DESCRIPTION

[0049] The present invention is further described below with reference to specific examples, but the examples do not limit the present invention in any form. Unless otherwise specified, the reagents, methods and equipment used in the present invention are conventional reagents, methods and equipment in the art.

[0050] Unless otherwise specified, the reagents and materials used in the following examples are commercially available.

[0051] The cationic polyacrylamide used in the examples and comparative examples is FLOSOFT TM FS 222 (brand: SNFSAS), its molecular weight range is 5000-1000000, its intrinsic viscosity range is 4-300mL / G, and its cationicity is 3-20%.

[0052] The microcapsules used in the examples and comparative examples have a particle size of 10 to 30 μm, with melamine resin as the wall material, essence or essential oil as the core material (Examples 1 to 5 and Comparative Examples 1 to 5), or benzalkonium chloride as the core material (Example 6).

[0053] Example Preparation of fabric softener

[0054] The fabric softeners of Examples 1 to 6 were formulated according to Table 1.

[0055] Table 1 Example fabric softener components (mass fraction, w / w)

[0056]

[0057] Preparation method:

[0058] ① Add microcapsules into water and homogenize at 500-1500r / min;

[0059] ② Then add dioctadecyl dimethyl ammonium chloride and ester quaternary ammonium salt (bistallow ester hydroxyethyl methyl ammonium methyl sulfate, disalmityl ester hydroxyethyl methyl ammonium methyl sulfate, disoleyl ester hydroxyethyl methyl ammonium methyl sulfate or disodium coconut oil ester hydroxyethyl methyl ammonium methyl sulfate), and stir evenly at 65-75°C;

[0060] ③Join FLOSOFT TM FS 222, after being evenly dispersed, is added with flavor and preservatives.

[0061] Preparation of comparative fabric softener

[0062] The fabric softeners of Comparative Examples 1 to 5 were prepared according to Table 2.

[0063] Table 2 Comparative Example Fabric Softener Components (mass fraction, w / w)

[0064]

[0065] Preparation method:

[0066] ① Add microcapsules into water and homogenize at 500-1500r / min;

[0067] ② Then add dioctadecyl dimethyl ammonium chloride and ester quaternary ammonium salt, and stir evenly at 65-75°C;

[0068] ③Join FLOSOFT TM FS 222, after being evenly dispersed, is added with flavor and preservatives.

[0069] Test Example 1 Centrifugal Stability Test

[0070] 1. Experimental Methods

[0071] Take the same volume of fabric softeners prepared in Examples 1 to 6 and Comparative Examples 1 to 5, centrifuge at 2000 r / min for 10 min, and determine the stability if the samples are uniform and free of particles, lumps, or flocs after centrifugation, otherwise they are unqualified.

[0072] 2. Experimental Results

[0073] The results are shown in Table 3. The centrifugal stability results of the fabric softeners prepared in Examples 1 to 6 were qualified, while the fabric softeners prepared in Comparative Examples 1 to 5 were unqualified. The above results show that dioctadecyl dimethyl ammonium chloride and FLOSOFT TM The combination of FS 222 can solve the problem of suspension stability of microcapsules; and the content of ester quaternary ammonium salt as the main ingredient of fabric softener does not affect the suspension stability of microcapsules.

[0074] Table 3 Centrifugal stability

[0075] Centrifugal stability results Phenomenon Example 1 qualified Homogeneous liquid Example 2 qualified Homogeneous liquid Example 3 qualified Homogeneous liquid Example 4 qualified Homogeneous liquid Example 5 qualified Homogeneous liquid Example 6 qualified Homogeneous liquid Comparative Example 1 Failure Multi-flocculation separation Comparative Example 2 Failure Multi-flocculation separation Comparative Example 3 Failure Small amount of flocculent separation Comparative Example 4 Failure Multi-flocculation separation Comparative Example 5 Failure Very little flocculent separation

[0076] Test Example 2 Thermal Stability Test

[0077] 1. Experimental Methods

[0078] The fabric softeners prepared in Examples 1 to 6 and the fabric softeners prepared in Comparative Examples 1 to 5 were placed in a 54°C oven for 14 days for a thermal acceleration test (the thermal acceleration test represents a 1-year shelf life). The samples were taken out after 14 days and the states of the different fabric softeners were observed after returning to room temperature. The samples were uniform and free of granules, lumps, or flocs, which was considered as a qualified standard for thermal stability. Otherwise, they were considered as unqualified.

[0079] 2. Experimental Results

[0080] The results are shown in Table 5. As shown in Table 5, in the thermal stability test experiment, the fabric softeners prepared in Examples 1 to 6 all remained stable after simulating a natural shelf life of 1 year, indicating that dioctadecyl dimethyl ammonium chloride and FLOSOFT TM The combination of FS 222 can stabilize the suspended microcapsules.

[0081] The fabric softener prepared in Comparative Example 1 is a mature preparation method of softener on the market, that is, ester quaternary ammonium salt is compounded with FLOSOFT TM FS 222, the fabric softener does not contain dioctadecyl dimethyl ammonium chloride compared to the fabric softeners prepared in Examples 1 to 5;

[0082] The fabric softener prepared in Comparative Example 2 is a preparation method of a softener that has been eliminated on the market. It only adds dioctadecyl dimethyl ammonium chloride, does not require other thickeners, and does not add FLOSOFT TM FS 222. After the thermal stability test, it was found that the thermal stability of the fabric softeners prepared in Comparative Example 1 and Comparative Example 2 was unqualified.

[0083] The fabric softener prepared in Comparative Example 3 has insufficient content of dioctadecyl dimethyl ammonium chloride, and the fabric softener prepared in Comparative Example 4 has insufficient content of FLOSOFT TM FS 222 is insufficient, and the thermal stability of both is also unqualified. The fabric softener prepared in Comparative Example 5 refers to the formula of Comparative Example 4. Although the content of microcapsules is reduced, microcapsules are still precipitated in the form of floccules during the thermal stability test.

[0084] Table 5 Thermal stability test

[0085] Thermal stability results Example 1 qualified Example 2 qualified Example 3 qualified Example 4 qualified Example 5 qualified Example 6 qualified Comparative Example 1 Failure Comparative Example 2 Failure Comparative Example 3 Failure Comparative Example 4 Failure Comparative Example 5 Failure

[0086] Test Example 3 Adsorption and release performance of microcapsules

[0087] 1. Experimental Methods

[0088] The fabric softener prepared in Example 6 has a long-lasting sustained-release sterilization function. Benzalkonium chloride is used as the core material of the microcapsule. The effective content of benzalkonium chloride is 30-40% (w / w). The minimum MIC for Staphylococcus aureus is 0.003%. Although it is a low-efficiency disinfectant, benzalkonium chloride has a relatively sensitive antibacterial ability against both Gram-negative and Gram-positive bacteria.

[0089] Therefore, this experiment uses Staphylococcus aureus as the bacterial species, and uses the 7.3 antibacterial rate method in QB / T 2738, and adopts the method of multiple full friction of fabrics and fixed water dissolution to release more of the contents of the microcapsules adsorbed on the fabric. If the antibacterial rate can reach more than 99%, it is judged that the microcapsules adsorbed on the fabric after washing have good adsorption stability and release performance. The specific experimental operation is as follows:

[0090] Take 10g of the fabric softener prepared in Example 6 and add it to 100g of water, then put in a new towel (pure cotton, 30-50g weight), soak it at room temperature for 30min, take it out and wring it out and dry it in the sun. The experimenter wears sterile plastic gloves, rubs the towel repeatedly for 10min, then soaks the towel with 300mL sterile water for 10min, and uses the obtained solution as the stock solution. The stock solution is used to act on Staphylococcus aureus for 10min and 15min respectively, and the antibacterial rate of the stock solution on Staphylococcus aureus is tested. If the antibacterial rate reaches more than 99%, it is judged to be qualified.

[0091] 2. Experimental Results

[0092] The results are shown in Table 6. From the results in Table 6, it can be seen that after the towel soaked in the fabric softener prepared in Example 6 has been soaked, dried, rubbed and soaked again, the core material (benzalkonium chloride) of its microcapsule can still play an obvious antibacterial effect, and the antibacterial rate under the condition of 10min action time reaches 98.6%, and the antibacterial rate under the condition of 15min action time reaches 99.1%, which meets the antibacterial requirements of QB / T 2738 national light industry standard and has a strong antibacterial effect. This shows that the fabric softener prepared by the method of the present invention, the microcapsules therein still have good adsorption and release properties during and after use.

[0093] Table 6 Staphylococcus aureus inhibition rate

[0094] Antibacterial rate The original solution obtained by soaking for 10 minutes 98.6％ Soak for 15 minutes to obtain the original solution 99.1％

[0095] The above embodiments are preferred implementation modes of the present invention, but the implementation modes of the present invention are not limited to the above embodiments. Any other changes, modifications, substitutions, combinations, and simplifications that do not deviate from the spirit and principles of the present invention should be equivalent replacement methods and are included in the protection scope of the present invention.

Claims

1. A composition for use in stabilizing the suspension of microcapsules in a fabric softener, characterized in that: The fabric softener comprises a cationic surfactant, and the composition comprises dioctadecyldimethylammonium chloride and cationic polyacrylamide.

2. The use according to claim 1, characterized in that: The cationic polyacrylamide has a molecular weight range of 5000 to 1000000, an intrinsic viscosity range of 4 to 300 mL / G, and a cationic degree of 3 to 20%.

3. The use according to claim 1, characterized in that: The cationic surfactant is an ester-based quaternary ammonium salt.

4. A method for stably suspending microcapsules in a fabric softener, characterized in that: Adding dioctadecyl dimethyl ammonium chloride and cationic polyacrylamide to a fabric softener; The mass fraction of the dioctadecyl dimethyl ammonium chloride in the fabric softener is not less than 1%; The mass fraction of the cationic polyacrylamide in the fabric softener is not less than 1%; The fabric softener comprises a cationic surfactant.

5. The method according to claim 4, characterized in that The cationic polyacrylamide has a molecular weight range of 5000 to 1000000, an intrinsic viscosity range of 4 to 300 mL / G, and a cationic degree of 3 to 20%.

6. The method according to claim 4, characterized in that The cationic surfactant is an ester-based quaternary ammonium salt.

7. A fabric softener, characterized in that: The fabric softener contains a cationic surfactant, microcapsules, dioctadecyl dimethyl ammonium chloride and cationic polyacrylamide; The mass fraction of the dioctadecyl dimethyl ammonium chloride in the fabric softener is not less than 1%; The mass fraction of the cationic polyacrylamide in the fabric softener is not less than 1%.

8. The fabric softener according to claim 7, characterized in that The cationic polyacrylamide has a molecular weight range of 5000 to 1000000, an intrinsic viscosity range of 4 to 300 mL / G, and a cationic degree of 3 to 20%.

9. The fabric softener according to claim 7, characterized in that: The cationic surfactant is an ester-based quaternary ammonium salt.

10. The fabric softener according to claim 9, characterized in that The ester-based quaternary ammonium salt is one or more of distallow ester hydroxyethyl ammonium methyl sulfate, dispalmityl ester hydroxyethyl ammonium methyl sulfate, disoleyl ester hydroxyethyl ammonium methyl sulfate and discocoyl ester hydroxyethyl ammonium methyl sulfate.

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