JPS5857475B2 - Hypoallergenic cleaning composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to mild detergent compositions, particularly mild shampoo compositions.

Most shampoos and light household cleaners contain anionic surfactants (e.g. sodium lauryl sulfate, sodium lauryl ether sulfate (SLES) and linear alkylbenzene sulfone-1) and surfactants that serve as foaming agents and stabilizers. based on the combination of agents such as tertiary amine oxides or alkanolamides.

All of these surfactants, especially the anionic surfactants, are strong eye irritants and cause mild to moderate skin irritation in some people.

Recently, there has been a trend toward using anionic surfactants mixed with amphoteric surfactants, and combining these compounds with ethoxylates of partial polyol esters of higher fatty acids to reduce irritation.

Products of this type, for example so-called baby shampoo compositions,
"Mildly irritating" according to the Draize eye irritation test.

Although it would be desirable in this regard to provide systems that are less harsh than those available today, an equally important objective is to have a system that allows control over the viscosity properties of the final product.

Most cleaning compositions of the form relevant here will be about 10 to
It is commercially available as a water system containing 30% active valve.

The standard method of increasing viscosity in the indicated range of solids has been to add common salt, which increases eye irritation.

The mild detergent system that makes up the aqueous cleaning composition (shampoo composition) of the present invention comprises a nonionic surfactant in the form of an alkylene oxide adduct of a partial glycerol ester of a detergent-grade fatty acid, a higher alkyl sulfate, and salts of higher alkaline ether sulfates, optionally containing a foam-stabilizing amount of an alkanolamide.

The shampoo composition of the present invention has a detergency that is at least comparable to that of known shampoo compositions (which contain as a component one of the same anionic surfactants as used in the present invention). Furthermore, it has fairly good hypoallergenic properties for the eyes as measured by the Draize eye irritation test.

This superior hypoallergenicity to the eyes is obtained according to the composition of the invention by the presence of nonionic surfactant in an amount at least equal to the weight of anionic surfactant.

Control of the viscosity of Chantu systems, whose concentrations range from 15 to 65% solids, is easily achieved by using an appropriate nonionic surfactant in equal or greater amounts by weight.

Anionic surfactants useful in the practice of this invention are standard commercially available products and need not be discussed in further detail here.

Applicable salts of anionic surfactants are those of alkali metal hydroxides, preferably sodium hydroxide, ammonium hydroxide, hydroxyalkylamines and the like.

Although nonionic surfactants are commercially available, it is appropriate to briefly describe the method of manufacture.

These nonionic surfactants are derived from partial glycerol esters of higher fatty acids.

Applicable higher fatty acids are so-called detergent grade fatty acids having about 10 to 18 carbon atoms.

acids, preferably in the saturated form; such partial esters consist primarily of a mixture of monoglycerides and diglycerides, with a monoglyceride content of from about 15 to
45 weight.

The remainder of the partial ester product is primarily the corresponding diglyceride.

Mixtures of these mono- and diglycerides can be readily prepared by glycerolysis of triglycerides in the presence of a base catalyst, preferably an alkali metal hydroxide.

Alternatively, it can be produced by direct esterification of glycerin with fatty acids.

In carrying out a preferred glycerolysis, the molar ratio of triglycerides to glycerin can be adjusted to obtain a reaction product having the desired monoglyceride content (usually equimolar).

The nonionic surfactant is an alkylene oxide adduct of the above partial glycerol ester.

Structurally, the nonionic surfactant has polyoxyalkylene chains of oxyethylene, oxypropylene, or oxyethylene and the remainder oxypropylene randomly distributed in a ratio of 2:1 to 4.5:1. It has characteristics.

The chain length of the polyox dialkylene group depends primarily on the amount of alkylene oxide used with respect to the partial ester.

Based on this, a range of 15 to 100 mol of alkyleneoxy L can be applied per mole of partial ester.

When using mixtures of propylene oxide and ethylene oxide, the promiscuous nature of the polyoxyalkylene chains is an important factor in providing a liquid product.

This promiscuity is achieved primarily by reacting ethylene oxide and propylene oxide with partial esters.

A preferred method consists in simultaneously adding both alkylene oxides in the selected ratio to the partial ester when carrying out the addition reaction.

Alternatively, the alkylene oxide can be added as a preformed mixture.

The process conditions that may otherwise be applied are in accordance with those of the standards observed when carrying out this reaction.

Such conditions include the use of suitable catalysts such as alkali metal hydroxides and processing temperatures preferably on the order of about 150 DEG to 180 DEG C.

The reaction is usually carried out in a closed system under a pressure of 2 to 10 atmospheres.

The nonionic surfactant is mixed with an anionic surfactant in an amount that provides all the compositions expressed as "minimal irritation" to the eye according to the Draize test.

A maximum average eye irritation rating of 1 to about 18 is classified as being amenable to this type of irritation.

The general method of evaluation and scoring for this test is described by J.
rmacol, and Exp, Ther,) 82,
No. 377 (1944) and section 191.12 of the Fenascil Hazardous Substances Act.

The ratio of nonionic surfactant to anionic surfactant to achieve stimulation in the above range is at least about 1 part by weight nonionic surfactant to 1 part by weight anionic surfactant to stabilize the bubbles. Including surfactants usually requires increasing the amount of nonionic surfactant.

Figure 1 shows typical ethoxylated nonionic surfactants and 5L
Figure 3 shows the eye irritation scores exhibited by various combinations of ES.

A maximum average eye irritation rating of 1 to about 18 is classified as "minimal" irritation.

Therefore, it can be seen that this low level of stimulation can be achieved when the nonionic surfactant and the anionic surfactant are mixed on an approximately equal weight basis.

Further, as shown in the graph, the effect of increasing the ratio of nonionic surfactant to anionic surfactant is that stimulus values significantly less than 10 are reached asymptotically at a ratio of about 2:1.

Exceeding this ratio will result in very small changes in eye irritation values, but as explained below, it is necessary to use a high ratio of nonionic to anionic surfactant from a viscosity control point of view. There may be or there may be benefits associated with its use.

The inclusion of bubble stabilizers has the effect of increasing the eye irritation properties of the system beyond what would normally be expected.

However, this increase is compensated for by moderately increasing the minimum ratio of nonionic surfactant to anionic surfactant.

Generally, the amount of foam stabilizer is based on the amount of anionic surfactant component present in the system and is about 20-25% of the anionic surfactant component.

If the amount of foam stabilizer is less than 20 mm, the foam stability will be less than optimal, and if it exceeds 25 mm, cleaning problems will occur. Therefore, 2 parts by weight of nonionic surfactant to 1 part by weight of anion. When a foam stabilizer is included within the indicated range of surfactants, all of the resulting compositions have an average eye irritation rating in the "minimal" irritation category.

As mentioned above, an important feature of the present invention is the ability to control the viscosity of the aqueous solution of the expected detergent system by appropriate selection of the nonionic surfactant component.

This feature is illustrated in Figure 2, which plots viscosity versus solids fraction of a typical aqueous shampoo system.

The active valve of the system used in this example corresponds to composition x8 of Example 1 (Table 1) and as such, on a solids weight basis,
Contains 3.9% S LES , 71.4% ethoxylated nonionic surfactant and 4.6% commercially available coconut oil jetanolamide.

The preparation of the two ethoxylates shown in Figure 2 is described in the Examples.

As shown in Figure 2, the viscosity of the aqueous system depends on the nature of the ethoxylated nonionic surfactant and the percent total solids in the system.

As shown, the greatest increase in viscosity was achieved by using a 40 molar adduct of a mixture of mono- and diglycerides derived from tallow, with 60 or 100 molar adducts derived from tallow.
The molar adduct gives an even greater increase in viscosity; on the other hand, 30 molar adduct substitution of a comparable partial ester mixture of coconut fatty acids gives an even greater solids level in obtaining the corresponding viscosity associated with the use of tallowate adducts. It can be made higher.

The mixtures in FIG. 2 are as follows.

Of the five curves in Figure 2, the curve drawn at the leftmost end shows the case of PEG40 glycertalloate alone (100%), and the curve drawn at the rightmost end shows the case of PEG30 glyceryl cocoaate alone (100%). The case is shown below.

Furthermore, complete control of viscosity properties can be achieved within the normal solids concentration range of detergent systems by appropriate blending of these two typical partial glycerol adducts.

In the specification, when the shampoo composition of the present invention is referred to as non-irritating or hypoallergenic, irritation means eye irritation.

The invention will be illustrated with reference to the following examples.

Example l 2335 parts (3,57 mol) of PEG30 glycerol cocoate refined coconut oil, 345
parts (3,75 mol) of glycerin and 5.4 parts of 50
% KOH aqueous solution was fed to a suitable reaction vessel.

The reaction mixture was heated to 110° C. with stirring and maintained under 20 mm vacuum for 1 hour.

The reaction mixture was then heated to 165° C. while nitrogen was introduced and maintained for 3 hours.

Mixture of the above monoglyceride and diglyceride 254.5
(0.6 mol) was fed into the pressure vessel.

The reaction vessel was purged twice with nitrogen and heated to 150°C.

A quantity of 800 parts (18°2 moles) of ethylene oxide was added over a period of 8 hours while maintaining a temperature of 150-160°C.

When the reaction mixture was cooled to about 110° C., 25% aqueous sulfuric acid was added to neutralize (pH 8) and the reaction mixture was filtered.

PEG40 glycerol tallowate By the force method described above, 1 mol of beef tallow was added to 1 mol of beef tallow in the presence of potassium hydroxide.
．． The mixture was reacted with 0.5 mol of glycerin to obtain a mixture of tallow monoglyceride and diglyceride.

The mixture was stripped and the partial ester mixture was then reacted with 40 moles of ethylene oxide according to the procedure described above and the ethoxylated product was cooled, stripped and filtered.

The stimulation data shown in Table 1 below relate to those derived by the Draize test method.

The foam stabilizer is coconut oil jetanolamide (baramide).
VARAMI DE) MAl (trademark), Sierex
Chemical Company Incorporated (She
rexChemical Company, inc.
)Met.

Percentage of active ingredient is shown, the balance being water.

Example 2 35 (3EO/PO) Glycerol Cocoate 233
5 parts (3,57 mol) refined coconut oil, 345 parts (3
, 75 moles) of glycerin and 5.4 parts of 50% potassium hydroxide were charged to a suitable reaction vessel.

The reaction mixture was heated to 110°C while stirring and heated to 20 m
The mixture was maintained under vacuum for 1 hour.

The reaction mixture was then heated to 165° C. while nitrogen was introduced and maintained for 3 hours.

140 parts of the above mixture of monoglyceride and diglyceride (
0.33 mol) was fed into the pressure vessel.

The reaction vessel was purged twice with nitrogen and heated to 150°C.

385 parts (8.75 mol) of ethylene oxide and 169
A preformed mixture of alkylene oxide containing 150 to 1 parts (2,91 moles) of propylene oxide was added to
The addition was carried out over a period of 8 hours while maintaining a temperature of 60°C.

When the reaction mixture was cooled to about 110°C, 25 cups of aqueous sulfuric acid solution was added to neutralize (pH 18), and then the reaction mixture was filtered.

82 (3EO/PO) Glycerol tallowate 1.05 mol of beef tallow in the presence of potassium hydroxide using the above method.
It was reacted with mol of glycerin to obtain tallow monoglyceride and diglyceride.

The water was removed by stripping and then a molar aliquot of the partial ester mixture was reacted with a preformed mixture of 61.5 moles of ethylene oxide and 20.5 moles of propylene oxide according to the procedure described above to form the alkoxylated product. Cool, strip, and serve.

Example 3 82 (3EO/PO) glycerol cocoate (Nonionic A) and 35 (2EO/PO) glycerol cocoaate (Nonionic B) were prepared by the general method described in Example 2.

An aqueous shampoo composition was prepared using the above adduct as a nonionic surfactant component, and an eye irritation test was conducted according to the Draize method.

The foam stabilizer in Composition 2 was commercially available coconut oil jetanolamide (Veramide MAI).

Other data regarding the composition of these systems and the test results obtained are shown in Table 2 below.

Alkoxylation can also be carried out using a mixture of ethylene oxide and propylene oxide.

The relationship between viscosity and solid content φ) of mixed propylene-ethylene alkoxylate is shown in FIG.

The active part of the system used in Fig. 3 is the composition A2 of Example 3.
(Table 2), which itself is 29.6 on a solid basis.
Contains wt% 5LES, 64.3% nonionic surfactant and 61% commercial jetanolamide.

The preparation of the nonionic surfactant is shown in Example 2.

The mixtures in Figure 3 are as follows.

As can be seen from the figures, the viscosity of the aqueous system depends primarily on the nature of the nonionic surfactant and the total solids content in the system.

As shown, the highest increase in viscosity was observed in the equilibrium reaction mixture of mono- and diglycerides derived from beef tallow, consisting of oxyethylene and the remainder oxypropylene with polyoxyalkylene chains randomly distributed in a ratio of 3=1. This can be achieved by using molar polyoxyalkylene adducts.

A similar 35 molar oxyalkylene adduct substitution of a comparable partial ester mixture of coconut fatty acids yields a viscosity comparable to the use of the above-mentioned tallowate adduct;
Higher solids contents can be obtained.

Furthermore, it is seen that control of viscosity properties can be achieved by proper blending of these two representative partial glycerol ester adducts at solids concentrations within the normal range of cleaning systems.

Example 3 (Table 2) demonstrates the low degree of eye irritation associated with typical detergent shampoo systems based on mixed propylene/ethylene alkoxylates.

Examples 4 to 6 In the present examples, shampoo compositions having the following compositions were obtained using ammonium lauryl sulfate, triamine lauryl sulfate, and sodium lauryl ether sulfate as anionic surfactants.

The nonionic surfactants A to C mentioned above were manufactured according to the general method described in the above examples, and have the following physical properties.

(where R is a group derived from stripped coco fatty acid) and is completely water soluble at acidic, neutral and basic pH values.

The appearance of this agent is a clear and colorless liquid, and the surface tension is 30.0 dynes/Cr1L (01% active content) and 30.
．． 9 dynes/Cll1 (0.05% active).

The above cleaning composition was tested for eye irritation according to the Draize method, and the following average irritation ratings were obtained.

As is clear from the above table, when higher alkyl sulfate salts are used as anionic surfactants, the average irritation score falls within the minimum irritation type range mentioned above, as in the case of higher alkyl ether sulfate salts. It was in.

In the case of the composition of Example 4, all the irritation was minimal in the conjunctiva of the eye, and there was no damage to the cornea of the eye or the iris of the eye.

[Brief explanation of drawings]

Figure 1 is a curve diagram showing the maximum irritation score according to the Draize eye irritation test obtained by combining the anionic surfactant 5LES and various amounts of representative nonionic surfactants, and Figure 2 is a curve diagram showing the maximum irritation score of shampoo. FIG. 3 is a curve diagram showing the relationship between solid content and viscosity of a shampoo system using an alkoxylate produced from propylene oxide and ethylene oxide.

Claims (1)

[Scope of Claims] 1(a) A cto-c having a monoglyceride content of about 15 to 45% by weight and the remainder substantially consisting of diglycerides.
Alkylene oxide adduct of partial glycerol ester of ts fatty acid, 1 mol of partial glycerol ester and ethylene oxide, propylene oxide or 2:1 to 4
．． an adduct selected from the group consisting of the above adduct prepared by reacting 15 to 100 moles of a mixture of ethylene oxide and propylene oxide in a molar ratio of 5:1; and (b) salts of higher alkyl sulfates and salts of higher alkyl ether sulfates. (a) an anionic surfactant;
A hypoallergenic shampoo composition containing active ingredients in a weight ratio of about 1:1 to 4:1. 2(a) CIO"C having a monoglyceride content of about 15 to 45 weight φ and diglycerides substantially constituting the remainder
15-100 of partial glycerol esters of 18 fatty acids
molar alkylene oxide adducts, prepared by reacting 1 mole of partial glycerol ester with 15 to 100 moles of ethylene oxide, propylene oxide or a mixture of ethylene oxide and propylene oxide in a molar ratio of 2:1 to 4.5=1. (b) an anionic surfactant selected from the group consisting of salts of higher alkyl sulfates and salts of higher alkyl ether sulfates; (c) an alkanolamide foam stabilizer;
(b) to (c) in a weight ratio of about 4:1 to 5:1 and (a
A hypoallergenic shampoo composition containing active ingredients in a weight ratio of about 2 to 5:1.