Detergent additive

Abstract

A detergent additive comprising an active material comprising one or both of tetraacetylethylenediamine, triacetylethylenediamine, and an interpolymer complex comprising both a proton-accepting (co)polymer and a proton-donating (co)polymer. [Selection diagram] None

Description

Background Art

[0001] Fabrics such as cloth for clothing are usually washed by bringing the fabric into contact with a detergent formulation that is a combination of detergent components and any other optional active substances such as bleaching agents. For ease of use, many detergent formulation users prefer an integrated product that incorporates the detergent and any active substances into a single product. Further, many users prefer this product to be liquid as compared to solid or granular products.

Summary of the Invention

Problems to be Solved by the Invention

[0002] One of the common washing active substances is tetraacetylethylenediamine (TAED). TAED functions as a peroxy bleach activator and a microbial control agent. TAED is widely used in solid detergent products. In liquid detergent formulations that contain some water, when TAED is hydrolyzed, TAED reacts to form N,N'-diacetylethylenediamine (DAED), which is not effective as a detergent active substance, thus losing its effectiveness as a detergent active substance. Therefore, TAED is not ideal as an active substance in aqueous detergent formulations when used without modification. Triacetylethylenediamine (TriAED) is another detergent active substance. A detergent additive containing one or both of TAED and TriAED suitable for use in liquid detergent formulations containing water is desirable.

Means for Solving the Problems

[0003] A detergent additive comprising an active substance containing one or both of tetraacetylethylenediamine or triacetylethylenediamine, and an intermolecular complex comprising both a proton-accepting (co)polymer and a proton-donating (co)polymer.

Modes for Carrying Out the Invention

[0004] The present disclosure describes improved detergent additives. In one aspect, the present disclosure describes a detergent additive comprising an active substance, such as tetraacetylethylenediamine (TAED), and an interpolymer complex. The interpolymer complex includes both a proton-accepting (co)polymer and a proton-donating (co)polymer. As used herein, "(co)polymer" refers to either a polymer or a copolymer. The improvement of the detergent additive described herein is an improvement in the hydrolysis stability of TAED, thereby improving the long-term stability of the aqueous detergent formulation. In the interpolymer complex, the proton-donating (co)polymer binds to the proton-accepting (co)polymer via a hydrogen bond. The interpolymer network defines the structure of the additive described herein, and the additive encapsulates the active substance.

[0005] The proton-donating (co)polymer is selected from the group consisting of poly(meth)acrylic acid, carboxymethylcellulose, ethylene acrylic acid copolymer, pectin, xanthan gum, and alginic acid. As used herein, "(meth)acrylic" refers to the functionality of both acrylic and methacrylic.

[0006] The proton-accepting (co)polymer is a homopolymer or copolymer selected from one or more of the group consisting of polyethylene oxide, polyethylene glycol, polypropylene glycol, polypropylene oxide, ethylene oxide / propylene oxide copolymer, polyvinyl alcohol, and methylcellulose.

[0007] The molar ratio of the proton-donating (co)polymer to the proton-accepting (co)polymer can be from 1:10 to 10:1. The molar ratio of the proton-donating (co)polymer to the proton-accepting (co)polymer is preferably from 1:5 to 5:1. The molar ratio of the proton-donating (co)polymer to the proton-accepting (co)polymer is more preferably from 1:2 to 2:1. The weight-average molecular weight of the proton-accepting (co)polymer is from 1,000 to 10,000,000. The weight-average molecular weight of the proton-accepting (co)polymer is preferably from 5,000 to 5,000,000. The weight-average molecular weight of the proton-accepting (co)polymer is more preferably from 10,000 to 1,000,000. The weight-average molecular weight of the proton-donating (co)polymer is from 1,000 to 10,000,000. The weight-average molecular weight of the proton-donating (co)polymer is preferably from 10,000 to 5,000,000. The weight-average molecular weight of the proton-donating (co)polymer is more preferably from 100,000 to 1,000,000.

[0008] The detergent additive may be prepared by mechanical mixing of the proton-donating (co)polymer, the proton-accepting (co)polymer and the active substance. The detergent additive may also be prepared by spray-drying a solution of the proton-donating (co)polymer and the proton-accepting (co)polymer onto the granules of the active substance. Optionally, a surfactant is included in the detergent additive preparation to enhance the encapsulation efficiency and uniformity. Examples of suitable surfactants are nonionic surfactants including aliphatic alcohol ethoxylates, alkylphenol ethoxylates, fatty acid ester ethoxylates, alkyl polyglycosides, ethylene oxide / propylene oxide copolymers including random and block copolymers, polyols, and ethoxylated polyols. When selecting a nonionic surfactant, it is important to consider that both the ethoxylated portion and the hydrophobic portion of the surfactant interact with the polymer complex and compete with the proton-accepting (co)polymer for the binding sites of the proton-donating (co)polymer.

[0009] During the preparation of the polymer complex (IPC), the effectiveness of IPC formation is determined by the pH of the prepared solution. The pH varies depending on the type of proton-donating and -accepting (co)polymers, the molecular weights of the proton-donating and -accepting (co)polymers, the degree of neutralization of the proton-donating (co)polymer, the type of other species present (such as surfactants or inorganic salts), and the ratio of the amounts of the proton-donating and -accepting (co)polymers and the selected active substance. Preferably, the pH of the prepared solution is 2 to 4 when the active substance is TAED or TriAED. The formation of the insoluble IPC complex has been observed to be maximized within this pH range.

[0010] The detergent additive is 90 wt% or less of TAED and 10 wt% or more of the polymer complex. In one example, the detergent additive is 75 wt% or less of TAED and 25 wt% or more of the polymer complex. Preferably, the detergent additive is 50 wt% or less of TAED and 50 wt% or more of the polymer complex.

[0011] As described herein, the additive encapsulates or partially encapsulates the active substance. As used herein, "encapsulated" refers to the active substance being bound or retained within the polymer complex. The additives described herein are designed to release the active substance during an inducing event (in the context of the present disclosure, the inducing event can be use in a washing machine). When referring to the encapsulated active substance, it refers to the active substance retained within the polymer complex prior to the inducing event. The additives prepared according to the method of the present disclosure have a encapsulation efficiency of 30 to 100%. Preferably, the additives prepared according to the method of the present disclosure have an encapsulation efficiency of 60 to 100%. More preferably, the additives prepared according to the method of the present disclosure have an encapsulation efficiency of 90 to 100%. As used herein, "encapsulation efficiency" refers to the proportion of the active substance that is likely to be encapsulated in the polymer complex of the additive.

[0012] The detergent additives described in this specification have better long-term stability in aqueous solution systems than TAED alone. When the detergent additive is used in a washing machine, TAED is released from the polymer complex, enabling TAED to be used in the cleaning system and its peroxy bleach activation function to be executed.

[0013] The methods described in this specification are suitable for the preparation of other types of solid powders. For example, the methods described in this specification include, but are not limited to, encapsulating fabric softeners, detergent active substances, bleach active substances, fertilizers, micronutrients, pest control agents (such as fungicides, bactericides, insecticides, acaricides, nematicides, etc.), biocides, microbial control agents, polymer lubricants, flame retardants, pigments, dyes, urea inhibitors, food additives, fragrances, pharmaceuticals, tissues, antioxidants, cosmetic ingredients (such as fragrances, perfumes, etc.), soil conditioners (such as antifouling agents, soil release agents, etc.), catalysts, diagnostic agents, and light protection agents (such as UV blockers).

Examples

[0014] Materials and Sample Preparation Materials TAED solid was purchased from Sigma-Aldrich and ground into powder using an 80 μm sieve. POLYOX Water-Soluble Resins WSR N-3000, WSR N-10, and WSR-205 were purchased from The Dow Chemical Company. WSR N-3000 and WSR N10 were separately dissolved in deionized water at a concentration of 7 wt%, while WSR-205 was dissolved in deionized water at a concentration of 5 wt%. A 35% polyacrylic acid (PAA) solution with a weight average molecular weight of 250,000 was purchased from Sigma-Aldrich. Methylcellulose (MC) with a number average molecular weight (Mn) of 40K was obtained from Sigma-Aldrich and dissolved in deionized (DI) water at a level of 2.5 wt% at room temperature.

[0015] Experimental Procedures The reagents and their amounts are summarized in Table 1. Encapsulation was carried out using two different procedures. In Example 1, the mixer-based procedure is described, and the remaining samples were prepared in a stirred flask.

[0016] In Example 1, according to the formulation described in Table 1, the polymer solutions (WSR N3000 and PAA prepared as above) were mixed in a plastic container equipped with a mechanical stirrer and stirred at 2500 rpm for 10 minutes to obtain a polymer blend. TAED powder was added to a metal blender set at medium speed, and the polymer blend was slowly added thereto. After all the polymer blend was added, the mixture turned into a white paste. Stirring was continued for 30 minutes. The contents were transferred to an aluminum pan and dried in a vacuum oven under reduced pressure at 40 °C for 16 hours. The resulting material is a white solid composite. It was pulverized into fine powder by a metal mixer using dry ice.

[0017] Examples 2 to 7 were adjusted using the procedure described in this paragraph. The sample amounts are summarized in Table 1. TAED, PEO, and methylcellulose solution were weighed in a 250 ml three-necked flask equipped with a mechanical stirrer. The mixture was stirred at 2500 rpm for 2 minutes, then the stirring speed was reduced and stirred at 1000 rpm for another 2 minutes. A predetermined amount of PAA solution was added to a 20 ml addition funnel, and the funnel was attached to the flask. The PAA solution was added dropwise to the flask while stirring at 1000 rpm. After all the PAA solution was added, the mixture was stirred for an additional 5 minutes. The product was separated by centrifugation and washed three times with DI water. The pH of the solution was in the range of 2.5 to 2.8. The product was dried as a thin layer at room temperature. The resulting material is a white solid composite. It was pulverized into fine powder by a metal mixer using dry ice.

Table 1

[0018] Material properties Differential scanning calorimetry Differential scanning calorimetry (DSC) measurements were performed using a TA Instruments differential scanning calorimeter, model Q2000. Samples of 5 - 10 mg were placed in sealed pans and analyzed by a scan at 10 °C / min from -50 to 200 °C. In the DSC measurements, heat flow curves were generated to verify the formation of the IPC by demonstrating the disappearance of the PEO dissolution endotherm compared to comparative tests carried out using only PEO, only PAA, only TAED, and an IPC without TAED. Effect of pH on IPC formation

[0019] Regarding the effect of pH on the intermolecular complex, the reagent ratios described in Example 2 were used. The formulation was divided into three parts, and TAED encapsulation was carried out in the same manner as described in Examples 2 - 7, except that after the complete addition of PAA, sodium hydroxide was used to adjust the pH of the reaction mixture to 3, 5, and 8. In the case of pH = 3, the solid precipitate obtained was separated by centrifugation, dried, and analyzed by DSC. At higher pH (pH = 5 and pH = 8), the solids obtained were paste-like. This aggregated solid was dried and also analyzed by DSC. The DSC analysis showed a PEO dissolution endotherm only for the formulation with pH = 3, while the formulations with pH = 5 and pH = 8 did not show a PEO dissolution endotherm.

[0020] Without being limited by theory, low pH promotes hydrogen bonding, but when PAA is deprotonated (such as in the case of the sodium salt), hydrogen bonding is not formed.

[0021] HPLC analysis to measure the hydrolysis of TAED to diacetylethylenediamine (DAED)

[0022] 0.5 grams of unencapsulated raw TAED and the encapsulated TAED powder from the above examples were added to 20 g of all (trademark) Mighty Pac (trademark) detergent and shaken for 10 minutes. One droplet (about 0.1 g) of each mixture was separately added to 10 g of 1:3 acetonitrile / H2O solvent and sonicated for 15 minutes to completely dissolve the TAED solid. The DAED concentration of the prepared samples was measured using an Agilent 1100 High-Performance Liquid Chromatography (HPLC) equipped with a quaternary pump and a diode array detector. The conditions of the HPLC method are summarized in Table 2.

Table 2

Table 3

[0023] As shown in Table 4, in the case of TAED that is not encapsulated at all, the DAED concentration increases dramatically, while in other examples encapsulated with the polymer complex, the DAED increased slowly. Since DAED is produced from the hydrolysis of TAED, the slow release characteristics of DAED indicate good encapsulation efficiency.

[0024] Furthermore, the encapsulation efficiency is not much affected by the molecular weight of PEO, such as in Example 5 (PEO Mw 400,000), and Examples 6 (PEO Mw 100,000) and 7 (PEO Mw 600,000) have very similar DAED concentrations. Examples 2 and 4, as well as Examples 1 and 3, show that even when the amount of TAED is increased, it is efficiently encapsulated by the polymer complex. When the ratio of PAA to PEO was changed, Examples 2, 3 and 5 also resulted in effective encapsulation. This application also provides, for example, the following inventions. [1] A detergent additive comprising an active substance containing one or both of tetraacetylethylenediamine or triacetylethylenediamine, and an intermolecular complex containing both a proton-accepting (co)polymer and a proton-donating (co)polymer. [2] The detergent additive according to [1], wherein the proton-donating (co)polymer is selected from the group consisting of poly(meth)acrylic acid, carboxymethylcellulose, ethylene acrylic acid copolymer, pectin, xanthan gum, and alginic acid. [3] The detergent additive according to any one of [1] to [2], wherein the proton-accepting (co)polymer is a homopolymer or copolymer selected from one or more of the group consisting of polyethylene oxide, polyethylene glycol, polypropylene glycol, polypropylene oxide, ethylene oxide / propylene oxide copolymer, polyvinyl alcohol, and methylcellulose. [4] The detergent additive according to any one of [1] to [3], comprising 90% by weight or less of the active substance and 10% by weight or more of the intermolecular complex. [5] The detergent additive according to any one of [1] to [4], comprising 25% by weight or less of the active substance and 75% by weight or more of the intermolecular complex. [6] The detergent additive according to any one of [1] to [5], comprising 90% by weight or less of the active substance and 10% by weight or more of the intermolecular complex. [7] The detergent additive according to any one of [1] to [6], comprising 25% by weight or less of the active substance and 75% by weight or more of the intermolecular complex. [8] The detergent additive according to any one of [1] to [7], wherein the pH of the detergent additive is 2 to 4. [9] The detergent additive according to any one of [1] to [8], wherein the encapsulation efficiency of the active substance in the additive is 60 to 100%.

Claims

1. A detergent additive, comprising a cleaning active substance consisting of one or both of tetraacetylethylenediamine or triacetylethylenediamine, and an intermolecular complex comprising both a proton-accepting (co)polymer and a proton-donating (co)polymer, wherein the cleaning active substance is bound or retained within the intermolecular complex, and the detergent additive comprises 50 to 75 weight percent of the cleaning active substance and 25 to 50 weight percent of the intermolecular complex based on the total weight of the detergent additive, wherein the proton-donating (co)polymer is poly(meth)acrylic acid having a weight average molecular weight of 100,000 to 1,000,000, wherein the proton-accepting (co)polymer is polyethylene oxide or the proton-accepting (co)polymer is polyethylene oxide and methylcellulose, and the polyethylene oxide has a weight average molecular weight of 10,000 to 1,000,000, and the molar ratio of the proton-donating (co)polymer to the proton-accepting (co)polymer is 1:2 to 2:

1. A detergent additive.

2. The detergent additive according to claim 1, wherein the proton-donating (co)polymer is poly(meth)acrylic acid, the proton-accepting (co)polymer is polyethylene oxide and methylcellulose, the cleaning active substance is tetraacetylethylenediamine, the pH of the solution in which the intermolecular complex binding or retaining the cleaning active substance is prepared is 2 to 4, and the detergent additive exhibits endothermic heat absorption of polyethylene oxide (PEO).

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