JP2000017295A - Automatic dish washer desiccant composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain compositions excellent in dispersibility suitable for automatic dish washers and free from bubbling by allowing a desiccant based on a strongly lipophilic polyhydric alcohol, fatty acid ester such as a propylene glycol fatty acid ester to be present together with gluconic acid or a gluconate salt. SOLUTION: A desired automatic dish washer desiccant composition comprises 6-40% polyhydric alcohol fatty acid ester having an HLB of 3-10 comprising at least one of a propylene glycol fatty acid ester, a glycerin fatty acid ester and a sorbitan fatty acid ester in which 0.1-15% at least one of gluconic acid and a gluconate salt is allowed to be present together and further, water and at least one ethyl alcohol, propylene glycol, glycerin and dipropylene glycol.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a desiccant composition for an automatic dishwasher, which has excellent dispersibility by adding gluconic acid to polyhydric alcohol fatty acid esters such as propylene glycol fatty acid esters and has no foaming. It is about.

[0002]

2. Description of the Related Art In general, after washing dishes with an alkaline detergent in an automatic dishwasher, a small amount of a desiccant for an automatic dishwasher (hereinafter referred to as a drying agent) is rinsed in dishwashing water in order to quickly dry the dishes. Agent).

[0003] By the addition of the desiccant, the water film adhering and remaining on the surface of the dishes and the like is thinned, and when the dishes exit the washing machine outlet, they are dried in a short time during standing even if they are already dried or not yet dried. If the desiccant is not put in the rinse water, the water adhering to the surface of the dishes will become water droplets, which not only lengthens the drying time, but also hard water components dissolved in the water. The so-called water spot (water spot) which adheres and remains white gives a dishwashing feeling to tableware.

[0004] Those containing a sucrose fatty acid ester as a main component (Japanese Patent Application Laid-Open No. 50-109188) and those containing a polyhydric alcohol fatty acid ester such as a propylene glycol fatty acid ester, a glycerin fatty acid ester, a sorbitan fatty acid ester as a main component (Japanese Patent Application Laid-open No. No. 58-21679) is known.

A desiccant containing a sucrose fatty acid ester having a surface tension as shown in Table 3 of JP-A-50-109188 is water-soluble and does not require a dispersant. There is a drawback in that it cannot be used in automatic dishwashers.

On the other hand, a desiccant containing a polyhydric alcohol fatty acid ester as a main component is a surfactant having a strong lipophilicity, and is therefore effective in uniformly thinning a water film adhered to the surface of tableware. Experimental evidence has shown that the most effective propylene glycol fatty acid esters, which are the most lipophilic, are effective in uniformly thinning the water film.

However, surfactants having a strong lipophilic property, such as propylene glycol fatty acid esters, do not disperse in water by themselves, and must be used in combination with a dispersant.

Regarding the importance of dispersibility and the mechanism of exhibiting an effect as a drying agent, see Japanese Patent No. 949243 (JP-A
No. 51-72983), page 9, upper column, left, line 9 to page 3, upper column, right, third line, but without a dispersant, a surfactant with strong lipophilicity was used as a desiccant. When used, it is sprayed as water and oil particles without being dispersed in the rinse water,
Not only oil droplets and water droplets adhere to the surface of the tableware, but rather repel water and do not form a thin water film, and oil marks (oil spots) are conspicuous, impairing the cleanliness of tableware.

On the other hand, polyhydric alcohol fatty acid esters such as propylene glycol fatty acid esters exhibit an effect as a desiccant only when they are finely dispersed with a dispersant and adhere to the surface. That is, the finer the dispersion, the thinner the water film, and the dried glass surprisingly emits gloss.

[0010]

On the other hand, recent automatic dishwashers tend to use a high-pressure injection compared to the conventional ones, because an alkaline detergent aqueous solution is strongly jetted from a nozzle to apply dirt to tableware to remove dirt. Therefore, bubbles easily form, but when bubbles form, not only does the foam overflow from the washing machine, but also air enters the pump that circulates and jets the cleaning liquid, which lowers the injection pressure and lowers the cleaning power. Dishwashers shall not generate foam.

However, as described above, surfactants having good dispersibility in polyhydric alcohol fatty acid esters such as propylene glycol fatty acid esters having strong lipophilicity have relatively high hydrophilicity, and thus are easily foamed. It causes foam trouble in automatic dishwashers.

[0012] As a method for suppressing the occurrence of foaming,
58-21679 and JP-B-59-12717 propose a method comprising as a main component a partial ester of a specific polyhydric alcohol and a specific fatty acid.

JP-B-59-187906 states that the use of a fatty acid ester of polyglycerin eliminates foam damage.

Polyglycerin fatty acid esters are good desiccants and good dispersants, but they are expensive,
In addition, there is a drawback that the dried tableware is slightly slimy.

Therefore, the inventors of the present application have found that a desiccant containing a polyhydric alcohol fatty acid ester having a strong lipophilicity such as propylene glycol fatty acid ester, glycerin fatty acid ester and sorbitan fatty acid ester as a main component is not foamed.
As a result of studying a method of dispersing extremely well, it has been found that one or more of gluconic acid and gluconate are extremely effective.

Japanese Patent Application Laid-Open No. 50-109188 discloses a desiccant comprising a sucrose fatty acid ester as a main component and sodium gluconate added thereto. The purpose of this is to significantly reduce the amount of water adhering to tableware, and to make the adhering water into a thin film instead of water droplets, but not to suppress foaming.

In fact, the numerical value of the surface tension of the sucrose fatty acid ester in Table 3 in JP-A-50-109188 is a monoester-rich sucrose fatty acid ester, and it is inevitable that foaming becomes extremely large.

[0018]

The present invention has been completed based on the above findings, and specifically, one or two of propylene glycol fatty acid ester, glycerin fatty acid ester and sorbitan fatty acid ester of HLB 3-10. Polyhydric alcohol fatty acid esters composed of 6 to 40%
In water, 0.1 to 15% of gluconic acid and / or gluconate is coexistent, and water and ethyl alcohol, propylene glycol, glycerin, dipropylene glycol are used in rind water. The present invention proposes a desiccant composition for an automatic dishwasher having good dispersibility.

Table 1 below shows the HLBs 3 to 10 used in the present invention.
Are examples of polyhydric alcohol fatty acid esters of
Propylene glycol C₆~
C₁₄Linear fatty acid ester, propylene glycol ole
Formic acid ester and glycerin C ₆~ C₁₆Linear saturation of
And oleic acid fatty acid ester, sorbitan C₈~ C₁₆straight
From one or more of chain fatty acids and oleic esters
Become.

[0020]

【table 1】

The commercially available products of propylene glycol fatty acid ester and glycerin fatty acid ester contain about 55% as monoester, and the vacuum distilled product shown in Table 1 has a content of 75%.
% Or more of monoester.

The polyhydric alcohol fatty acid ester used in the present invention is insufficiently dispersed even if gluconic acid and gluconate are added at an HLB of 3 or less, and the polyhydric alcohol fatty acid ester at an HLB of 10 or more has poor drying properties.

The polyhydric alcohol fatty acid ester of HLB 3 to 10 is contained in the composition in an amount of 6 to 40%, preferably 10 to 40%.
%. If it is less than 6%, the drying property is insufficient, and if it is more than 40%, gluconate cannot be sufficiently added and dissolved.

The gluconic acid and gluconate used in the present invention are gluconic acid and gluconates such as sodium gluconate, potassium gluconate, calcium gluconate, and the like. If it is 15% or less, the dispersing ability is not obtained, and if it is 15% or more, the compounding ratio of the fatty acid esters becomes low.

These components are liquids composed of water and one or more of ethyl alcohol, propylene glycol, glycerin and dipropylene glycol which dissolve these components.

[0026]

Embodiments of the present invention will be described below. Hot water at 60 ° C. was put into a Hobart door type washing machine, and Dattershell LK (a product of Tipol Co., Ltd.) was dissolved to a concentration of 0.2%. on the other hand,
The rack was set with 10 glasses that had been soiled with milk and air-dried for 1 hour. After washing for 45 seconds, a desiccant having various compositions shown in Table-2 was dissolved to a concentration of 1/20000, and the temperature was 7 L at 80 ℃
After rinsing by spraying rinse water from a nozzle, the rack was taken out and allowed to air dry.

The water spot, oil spot and gloss of the dried glass were observed. Foaming was observed by taking out the rack, inserting an empty rack, and further spraying only the cleaning liquid. The results are shown in Table 2.

[0028]

[Table 2]

In Comparative Example 1, since sucrose laurate was added as a dispersant, the finish of the glass was good, but the gloss was low and the foaming was high.

In Comparative Example 2, since the compounding ratio of sucrose laurate was small, dispersion was insufficient and the finished glass had many water spots and much foaming.

In Comparative Example 3, although propylene glycol oleate of HLB2.5 was blended and sucrose fatty acid ester was not blended, despite the fact that potassium gluconate was blended at 15%, dispersion was not possible. The glass finish is poor because it is sufficient. However, there is no foaming.

Since Examples 1, 2, 3, 4, 6, and 7 all have the compounding ratio of the present invention, the finish of the glass is very good in gloss and little foaming.

[0033]

In summary, according to the present invention, automatic dishwashing is achieved by allowing gluconic acid or gluconate to coexist with a desiccant based on a polyhydric alcohol fatty acid ester having a strong lipophilic property such as propylene glycol fatty acid ester. It is possible to obtain a composition which is very dispersible and has no foaming, which is suitable for a machine.

Claims (1)

[Claims] 1. A polyhydric alcohol fatty acid ester comprising one or more of propylene glycol fatty acid ester, glycerin fatty acid ester and sorbitan fatty acid ester having an HLB of 3 to 10 and 0.1 to 15% of gluconic acid. And a desiccant composition for an automatic dishwasher, wherein one or more gluconates coexist, and further comprising water and one or more of ethyl alcohol, propylene glycol, glycerin and dipropylene glycol.