RU2362801C2 - Creamy agent for improving softness of linen during washing - Google Patents

Abstract

FIELD: personal use items.

SUBSTANCE: creamy agent for improving smoothness of linen during washing contains potassium metaphosphate, with viscosity of 200 mPa·s or more in aqueous solution. Viscosity is determined with addition of 2 g potassium phosphate to 50 ml water, stirring the mixture for 1 minute, addition of a solution obtained from dissolving 4 g sodium metaphosphate in 50 ml water, stirring the mixture for 3 hours and determination of viscosity in a B-type viscometer at 25°C. Besides phosphorous, potassium metaphosphate contains arsenic in amount of 0-0.7 mmol in 1 kg of potassium metaphosphate and, besides potassium, sodium in amount of 0-100 mmol in 1 kg of potassium metaphosphate. The washing composition contains a creamy agent which improves smoothness of linen during washing and a solubilising substance. The manual washing method is realised at concentration of potassium metaphosphate in water equal to or greater than 30 mg/l, and weight ratio of water to linen equal to or greater than 2. Potassium metaphosphate is obtained by spray-drying an aqueous solution of potassium dihydrogen phosphate and phosphoric acid or an aqueous solution of potassium dihydrogen phosphate, phosphoric acid, arsenic and/or sodium, and burning the spray-dried product.

EFFECT: increased smoothness (softness) of linen and hand skin, prevention of damage to fabric during washing, easier manual washing.

13 cl, 2 tbl, 14 ex

Description

FIELD OF THE INVENTION

This invention relates to a tool for improving the smoothness of laundry during washing, which makes it possible to avoid damage to the fabric. More specifically, this invention relates to a laundry additive based on new technical ideas: the possibility of hand washing is improved by washing with reduced effort by improving the smoothness between items during hand washing and by the degree of friction of the laundry when washing (numbers abrasive contact per unit time), which is likely to be increased, and damage to items that need to be washed, due to friction between items of linen and cut damage, and damage due to friction, widely regarded as one hand, as a result of friction on the hands of one another, are reduced. In addition, the present invention relates to a detergent composition comprising the aforementioned agent for improving the smoothness of laundry. In addition, this invention relates to a method of hand washing in the presence of potassium metaphosphate. In addition, this invention relates to a method for preventing damage to the laundry by, for example, increasing the smoothness between the fibers, damaging the fibers that cause their shape to be lost due to mechanical force, such as stirring in washing machines.

BACKGROUND OF THE INVENTION

Methods of washing can be roughly classified into hand wash and machine wash. Recently, due to the widespread use of washing machines, washing in washing machines tends to expand. However, there is still a need for handwashing in terms of easy removal of dirt stains and economic benefits.

Therefore, developments have been made on detergents with preferred handwash properties. For example, Japanese Unexamined Patent Laid-Open No. Hei 10-504056 describes a method of improving skin irritation during hand washing by incorporating a specific ratio of anionic surfactant anionic surfactant, cationic surfactant and nonionic surfactant. In addition, with regard to the regulation of bubble formation, highly foaming surfactants are generally known, such as LAS and AS for increasing foam; a nonionic surfactant such as polyoxyethylene alkyl ether for regulating the formation of bubbles; and soaps to improve the removal of foam when rinsing. In particular, the Japanese Patent Publication No. Hei 8-13987 disclosed discloses a detergent composition having excellent solubility, foaming and rinsing properties by containing an anionic surfactant, a specific nonionic surfactant and a fatty acid soap in a specific ratio .

However, studies on improvement methods to facilitate hand washing (smoothness when items to be washed are rubbed) have not yet been made.

SUMMARY OF THE INVENTION

This invention relates to:

[1] a creamy product for improving the smoothness of laundry when washing, containing potassium metaphosphate, having a viscosity in an aqueous solution of 200 MPa · sec or more, the viscosity being determined under the following conditions: adding 2 g of potassium metaphosphate to 50 ml of water, stirring the mixture for 1 minutes, adding a solution obtained by dissolving 4 g of sodium tripolyphosphate (available for purchase from Shimonoseki Mitsui Chemicals, Inc.) in 50 ml of water, stirring the mixture for 3 hours and determining the viscosity using a B-type viscometer at 25 ° C;

[2] a creamy means for improving the smoothness of laundry during washing in accordance with the above [1], wherein the chain-forming element, except phosphorus, is contained in an amount of 0 to 0.7 mmol per 1 kg of potassium metaphosphate, and the chain-modifying element, except K is contained in an amount of from 0 to 100 mmol;

[3] a creamy means for improving laundry smoothness in accordance with the above [1] or [2], wherein the potassium metaphosphate is obtained by spray drying an aqueous solution of potassium dihydrogen phosphate and phosphoric acid or an aqueous solution of potassium dihydrogen phosphate, phosphoric acid forming a network an element other than phosphorus and / or a network-modifying element other than K and burning a spray dried product;

[4] a creamy means for improving the smoothness of the laundry when washing in accordance with any one of the above [1] to [3], and a creamy means for improving the smoothness of the laundry when used for hand washing,

[5] a detergent composition containing a creamy means for improving the smoothness of the laundry during washing in accordance with any one of the above [1] to [4] and a solubilizing agent;

[6] the detergent composition according to the above [5], wherein the detergent composition is a laundry detergent powder;

[7] the detergent composition according to [5] or [6] above, wherein the solubilizing agent comprises an ion source for substitution in an amount of at least 0.5 equivalent of potassium ion in potassium metaphosphate;

[8] a detergent composition according to any one of the above [5] to [7], further comprising a surfactant and / or a main component;

[9] the detergent composition according to the above [8], further comprising a filler that captures metal ions, having the ability to capture calcium ions at a level of 100 mg CaCO ₃ / g or more, in an amount of 5% by weight or more;

[10] the detergent composition as described above [9], wherein the metal ion-capturing substance is a water-soluble organic substance;

[11] the detergent composition according to any one of the above from [5] to [10], further comprising silicate;

[12] the detergent composition according to any one of the above from [5] to [11], further comprising phosphate;

[13] a hand-washing method, the washing being carried out under conditions of a concentration of potassium metaphosphate, as defined in any one of the above [1] to [3], in water of 30 mg / l or more and a liquid ratio of 2 or more; and

[14] a method for producing potassium metaphosphate as defined in [2] above, comprising the step of spray drying from an aqueous solution of potassium dihydrogen phosphate and phosphoric acid or an aqueous solution of potassium dihydrogen phosphate, phosphoric acid, a detergent composition according to any one of the above [5] ] according to [7], further comprising a network-forming element, in addition to phosphorus, and / or a network-modifying element, in addition to K, and burning the spray dried product.

DETAILED DESCRIPTION OF THE INVENTION

This invention relates to a creamy detergent for improving smoothness during washing, capable of improving smoothness between items to be washed by hand washing, so that washing can be performed with reduced force, and washing is facilitated by improving the degree of friction of the items during washing (number of touches per unit time) and additionally able to carry out the so-called hand-protecting action, in which the skin after hand washing feels soft and smooth, and the so-called yuschee laundry operation in which loss of its shape due to mechanical impact such as stirring in washing machines can be avoided; creamy smoothness (softness) improving means for hand washing; a detergent composition containing these smoothness (softness) improving agents, and a hand wash method in which smoothness (softness) is improved by rubbing objects that are to be washed with each other during hand washing.

By using the creamy smoothness (softness) improving agent of the present invention, effects such as smoothness between items to be washed during hand washing are enhanced, so that washing can be performed with reduced force, and hand washing is facilitated by increasing the speed of the rubbing objects to which items that need to be washed (the number of contacts per unit time). And also effects such as the so-called hand protection can be implemented, which is achieved by improving the sensations of hand washing, and so-called tissue protection can be implemented.

These and other advantages of the present invention will be apparent from the following description.

As a result of intensive research by observing a completely new property of “smoothness, softness”, when the items to be washed rub against each other during washing in order to satisfy the need for convenient handwashing, it was found that the above problems can be solved by adding, separately, improving the smoothness (softness) of the laundry detergent containing potassium metaphosphate into the detergent composition for hand washing or the use of a detergent composition containing the above crema heat of improving smoothness (softness) means for linen. Thus, the present invention has been completed.

<Creamy laundry softener>

A creamy smoothing (softening) laundry detergent can be used by mixing the improving agent with a detergent, or it can be directly added separately from the detergent during washing.

The creamy smoothness improving softener of the present invention contains potassium metaphosphate having a particular viscosity. Specific examples thereof include potassium metaphosphate alone or a mixture of potassium metaphosphate with other substances.

Potassium metaphosphate is described below. In addition, the other substances mentioned herein may be any substances commonly used in a detergent composition without suppressing the effects of potassium metaphosphate. For example, sodium sulfate, zeolite, polyethylene glycol and alkyl sulfate or the like can be used accordingly.

The amount of potassium metaphosphate is preferably from 30 to 100% by weight, more preferably from 50 to 100% by weight of a creamy smoothness improving softener.

When the creamy smoothing (softness) improving agent having the above composition consists of one potassium metaphosphate, potassium metaphosphate or potassium metaphosphate can be used directly, converted to a fine powder by processing to powder.

In addition, when the creamy smoothing (softness) improving agent for laundry is a mixture of potassium metaphosphate with other agents, the creamy smoothing (softening) improving agent for laundry can be made by mixing these components in a known manner.

The creamy smoothness (softness) improving agent for laundry of the present invention serves to improve the smoothness (softness) between items to be washed during a hand wash, thereby facilitating hand washing to improve the sensations of a hand wash and to protect hands as well as protect the laundry. Accordingly, the present invention also relates to a creamy agent for improving smoothness (softness) during hand washing.

The form of the creamy agent for improving the smoothness (softness) of the laundry (hereinafter referred to simply as the “creamy agent for improving the smoothness (softness)" is not particularly limited. The form may be any of the forms of the substance, such as powders, granules, liquids or thick suspensions / pastes. smoothing showed up quickly with respect to the laundry, it is preferable to use a creamy smoothing improving agent in the form of a powder or granules.

Preferably, the creamy smoothing (softness) improving agent is contained in the detergent composition in terms of ease of use and solubility. Here, the aforementioned creamy smoothing (softness) improving agent is not limited to the composition, form or method of manufacturing the detergent composition used, and can exert its effects in all detergent compositions containing a solubilizing agent, which will be described later.

<Detergent Composition>

One of the important characteristics of the detergent composition of the present invention is that the detergent composition contains the above creamy smoothing (softness) improving agent and a solubilizing agent. Since the detergent composition has the above characteristics, the following effects are manifested: the washing liquid, in which the washing composition is dissolved during washing, becomes a lotion-like viscous solution, so that smoothing (softness) improves between items to be washed, also during hand washing, and washing can be performed with reduced effort and the possibility of hand washing, so that there is an improvement in relation to the tendency to increase the degree of abrasion of items to be washed, and, in addition, Appears effects gentle impact on the hands, in which dry skin after washing the hands is experienced as a gentle and smooth, and the effects of exposure to the careful clothes items in the wash.

The amount of the creamy smoothing (softness) improving agent is preferably 0.1 to 30% by weight, more preferably 0.5 to 20% by weight of the detergent composition.

The detergent composition can be presented in any of the forms, such as powders, granules, liquids or pastes, or can be made in the form of an aggregate, tablets or the like by recycling. In order for smoothing to manifest itself more quickly in laundry items, it is preferable that the detergent composition be in the form of powder or granules.

And furthermore, the detergent composition is preferably used in the form of a detergent powder for washing.

Here, the washing liquid, as described, refers to a washing liquid, such as a liquid in which the aforementioned detergent composition is dissolved or suspended.

Each of the components used in this invention will be described hereinafter.

Potassium metaphosphate

Potassium metaphosphate used in this invention refers to a substance that has a viscosity in an aqueous solution of 200 mPa · s or more, preferably 250 mPa · s or more, more preferably 300 mPa · s or more, when the viscosity is determined using the method for determining viscosity, which is described below. Since potassium metaphosphate having a specific viscosity as described above has the advantage of providing a markedly higher softness and exhibiting a successful effect as a hand wash detergent, there is an advantage that the amount of creamy softening improving agent can be reduced by adding a creamy laundry softener containing potassium metaphosphate to a detergent mixture.

Here, the viscosity of an aqueous potassium metaphosphate solution is obtained by analysis with the steps of adding 2 g of potassium metaphosphate to 50 ml of water, stirring the mixture for 1 minute, adding a solution prepared by dissolving 4 g of sodium tripolyphosphate (available from Shimonoseki Mitsui Chemicals, Inc.) to 50 ml of water, stirring the mixture for 3 hours and determining the viscosity using a B-type viscometer at 25 ° C.

The potassium metaphosphate used in this invention is usually obtained by the method represented by the following:

nKN ₂ PO ₄ → (KRO ₃ ) _n + nН ₂ О

In particular, potassium dihydrogen phosphate (KH ₂ PO ₄ ) is heated to effect intermolecular dehydration to form potassium metaphosphate. Factory products with different degrees of polymerization are obtained depending on factors such as the difference in heating temperature and heating time. The higher the temperature of the dehydration reaction, the greater the degree of polymerization. There is a correlation between the degree of polymerization and the softness, and the molecular weight of potassium metaphosphate is preferably 10,000 or more, more preferably 100,000 or more, more preferably 200,000 or more, even more preferably 500,000 or more from the point of view of improvement with respect to hand washability. The molecular weight of potassium metaphosphate is preferably 50,000,000 or less, more preferably 20,000,000 or less in terms of availability.

Potassium metaphosphate is represented by the general formula (KPO ₃ ) _n , and its structure is represented by the following formula:

Here, potassium metaphosphate has a structure in which the tetrahedrons of PO ₄ are bonded (or polymerized) to each other with the participation of an oxygen atom to form a network of polyphosphate anions and coordinated with a neutralized potassium ion to balance the electric charge of polyphosphate anions. As shown in the above structure, an element, such as phosphorus, for forming a network of phosphate anions is called a "network-forming element", and an element, such as potassium, for regulating the electric charge of a network of polyphosphate ions, is called a "network-modifying element".

The potassium metaphosphate used in this invention may contain a network-forming element, in addition to phosphorus, in a specific amount, and a network-modifying element, in addition to potassium, in a specific amount. A network-forming element, in addition to phosphorus, or a network-modifying element, in addition to potassium, may be contained in the raw material to produce potassium metaphosphate or may be included during the production process.

It is well known that potassium metaphosphate can be used as the main component for detergents. With this application, there are no restrictions on the network forming element other than phosphorus or the network modifying element other than potassium, and the effect as a filler should not be seriously attenuated, regardless of the ratio of the components. On the other hand, the potassium metaphosphate used in this application of the present invention presents a special situation in which a beneficial effect in the present invention can occur only when the content of these elements is limited to a specific interval.

An additional phosphorus source of the industrially used phosphate compound, which is used as a raw material for potassium metaphosphate, includes the so-called phosphate ore, obtained as a natural source, which contains large amounts of calcium phosphate and the like. Phosphate ore mined from natural deposits is industrially processed into a phosphate compound, such as phosphoric acid (or phosphate) through the form of yellow phosphorus, phosphorus oxide or the like. When the purification steps are not included in the process or the purification is unsatisfactory, the phosphate compound obtained from the mined phosphate ore containing a large amount of a network-forming element, in addition to phosphorus, such as arsenic, is recovered from the mined phosphate ore. According to standard practice, high-level cleaning is not carried out for inexpensive grades and grades for industrial use of phosphate compounds for use in detergents and the like, so that the phosphate compound contains a network element in addition to phosphorus in large quantities. The content of the network-forming element, in addition to phosphorus, varies, depending on the different deposits of phosphate ore or the processes of its processing. The commercially available phosphate compound of a commercial grade typically contains from a few dozen to 100 ppm by weight of a network forming element other than phosphorus.

On the other hand, a potassium source used in industry as another raw material for potassium metaphosphate includes potassium hydroxide obtained by electrolysis of potassium chloride. Potassium chloride is obtained industrially by precipitation from a mixture containing impurities such as carnallite, cainite, sylvite or Halzsalz. Industrial grade potassium chloride, however, also contains other components that cannot be removed by precipitation, such as sodium chloride or magnesium chloride, in large quantities. Since these components, in addition to potassium chloride, are carry out in potassium hydroxide obtained by electrolysis, industrial grade potassium hydroxide contains a network-modifying element, in addition to potassium, in large quantities.

Specialists in this field who carry out all or part of the types of processes for producing a phosphate compound for processing phosphorus compounds to produce a phosphate compound from phosphate ore, almost without exception, receive an industrial product, in addition to phosphate compounds of potassium, which can serve as raw material for potassium metaphosphate. In order to effectively use their capabilities, it has been generally accepted in general practice that phosphorus processors use together such industrial equipment as a reaction boiler, dryer and kiln for, for example, processing a sodium phosphate compound obtained from a phosphoric acid source and a source sodium, obtaining a compound of potassium phosphate, which can serve as a raw material for potassium metaphosphate or obtaining potassium metaphosphate itself. When the control of the installation and process, such as the order of the types of products to be obtained and the purification of technological equipment, when the types of products are changed, is inadequately performed, this leads to an increase in the level of undesirable components when applying this invention at the stages of the technological process, even if all of the various raw materials are provided materials favorable for the preparation of potassium metaphosphate of the present invention.

Various raw materials for the preparation of potassium metaphosphate of the present invention have been studied in detail for the presence of other components besides phosphorus and potassium. Preferably, when these components are subjected to cleaning or other means of exposure in some cases. For example, as an example of a case where the network-forming element, in addition to phosphorus, is contained in a preferred range, it is preferable to use a potassium phosphate compound such as potassium dihydrogen phosphate, which is highly purified and is present as a dietary supplement in the potassium metaphosphate preparation of the present invention.

A network-forming element other than phosphorus, or a network-modifying element other than potassium, is included in potassium metaphosphate to exhibit the same level of action as phosphorus or potassium, and to satisfactorily exhibit the desired effect on potassium metaphosphate of the present invention, since this element is contained in the appropriate amount. The network forming element, in addition to phosphorus, is not particularly limited, and examples thereof are B, As, Si, Ge, Sb, Ti, Sn, Al, Zr and the like. The content of the network forming element (NWF; OSE) is preferably from 0 to 0.7 mmol, more preferably from 0.0001 to 0.4 mmol, more preferably from 0.0002 to 0.1 mmol per 1 kg of potassium metaphosphate.

The network modifying element, in addition to potassium, is not particularly limited, and examples thereof are Fe, Mg, Ni, Zn, Co, Ca, Sr, Ba, Li, Na, Rb, Cs and the like. The content of the network modifying element (NWM; ITU) is preferably from 0 to 100 mmol, more preferably from 0.0001 to 75 mmol, or even more preferably from 0.0002 to 25 mmol per 1 kg of potassium metaphosphate.

The content of the above network-forming element or network-modifying element is indicated by a value determined by an atomic absorption spectrophotometer or an inductively coupled plasma emission spectrophotometer (ICP), as indicated hereinafter.

In addition, in this invention, the molar ratio of potassium to phosphorus (hereinafter referred to as the K / P ratio) is not particularly limited, and this molar ratio is preferably less than 1, more preferably from 0.999 to 0.94, even more preferably from 0, 99 to 0.98. When the K / P ratio is less than 1, the polyphosphate anions in the potassium metaphosphate are given the opportunity to form a crosslinked structure, as shown by the following formula:

thus, the compound undergoes structural transformation from a polymer with a one-dimensional chain to a two-dimensional multilayer polymer, which gives some advantages in that the degree of polymerization is further increased and even higher smoothing (softening) can be manifested more easily. Here, the K / P molar ratio can be determined by the method described in the examples below.

The amount of potassium metaphosphate in the detergent composition is preferably 0.5 parts by weight or more, more preferably 1 part by weight or more, more preferably 3 parts by weight or more, even more preferably 5 parts by weight or more, even more preferably 7 parts by weight or more , even more preferably 10 parts by weight or more per 100 parts by weight of the detergent composition in terms of improving the possibilities for hand washing. In addition, the amount of potassium metaphosphate in the detergent composition is preferably 30 parts by weight or less, more preferably 20 parts by weight or less per 100 parts by weight of the detergent composition in order to maintain ease of handling of items to be washed after washing.

Moreover, when the washing liquid is prepared by dissolving the detergent composition in water, the concentration of potassium metaphosphate in water is preferably 15 mg / L or more, more preferably 30 mg / L or more, even more preferably 60 mg / L or more A vision of superior handwashing capabilities. Also, this concentration is preferably 3000 mg / L or less, more preferably 1500 mg / L or less, even more preferably 1000 mg / L or less from the point of view of maintaining ease of handling of items to be washed after washing. Preferably, when the above concentration of potassium metaphosphate in water is increased in accordance with a decrease in the liquid ratio, which is the weight ratio of water to items of laundry, i.e. weight of water / weight of items of laundry, increasing the hardness of the water of the washing liquid (washing liquid) and increasing the amount of non-ionic surfactant in the detergent composition and increasing the ratio of the amount of non-ionic surfactant and the components of the surfactant as a whole in the detergent composition .

The following will explain the method for producing potassium metaphosphate. Potassium metaphosphate can be obtained by condensation by dehydration of potassium dihydrogen phosphate at high temperature, as described above. In the present invention, potassium metaphosphate is prepared by mixing potassium dihydrogen phosphate and phosphoric acid, and then condensing by dehydrating the mixture at high temperature to bring about a specific K / P ratio.

Preferably, when potassium dihydrogen phosphate and phosphoric acid are mixed with each other until homogeneous. Potassium metaphosphate melts at a temperature of 800 ° C or higher to obtain a molten solution. When the preparation is carried out at a temperature of 800 ° C or higher to obtain a molten state, mixing to homogeneity is carried out at a temperature of 800 ° C or lower, since the reaction occurs in the solid state, preferably when the raw materials are homogenously mixed before and then the mixture is burned, having in view of achieving homogeneity. As a specific example of mixing raw materials, since both potassium dihydrogen phosphate and phosphoric acid are water soluble, a process comprising the steps of mixing these components to form a homogeneous aqueous solution and spray drying the aqueous solution is preferred. An example of mixing an aqueous solution containing a source of phosphorus, such as phosphoric acid, or an aqueous solution containing a source of potassium, such as potassium hydroxide, is preferably substantially the same as the above process to achieve the effect of the present invention. Alternatively, potassium dihydrogen phosphate in powder form can be supplied to the mixer rotating at a high speed, and phosphoric acid in the form of a liquid can be sprayed or dripped inside. The mixer is preferably a mixer for solids, and examples thereof are, for example, a horizontal cylindrical mixer, a V-mixer, a double conical mixer, a tape screw mixer, a conical screw mixer, a high speed mixer, a rotary disk mixer, a fluidized bed mixer, free fall mixer and agitating mixer and the like. Of these, a high-speed mixer is preferred, which is capable of even more homogeneous mixing by high-speed mixing. In addition, in accordance with a process including the steps of dissolving potassium dihydrogen phosphate in water, mixing the solution with phosphoric acid, and then spray drying the mixture, a mixed powder is obtained in which potassium dihydrogen phosphate and phosphoric acid are mixed even more uniformly.

The above aqueous solution obtained by mixing, for example, potassium dihydrogen phosphate and phosphoric acid, may contain a network-forming element, in addition to phosphorus, and / or a network-modifying element, in addition to potassium from the point of view of homogeneity of potassium metaphosphate.

The burning temperature at which the condensation reaction is carried out is preferably 400 ° C or higher, more preferably 500 ° C or higher, more preferably 600 ° C or higher from the point of view of smoothing (softness) after immersion, and the burning temperature is preferably 1500 ° C or lower, more preferably 1200 ° C or lower, more preferably 800 ° C or lower in terms of energy consumption.

The potassium metaphosphate obtained by burning is preferably sprayed using a spray gun to a particle size at which the smoothing effect in the detergent mixture can easily manifest.

As the particle size of potassium metaphosphate, the average particle size is preferably 100 μm or more, more preferably 150 μm or more, more preferably 200 μm or more from the point of view of maintaining the effect of improving handwash capabilities, and the average particle size is preferably less than 500 microns, more preferably less than 400 microns, even more preferably 300 microns from the point of view of solubility (suppression of deposition of insoluble residues or deposition on linen (clothing). In addition, when potassium metaphosphate is mixed to form granules, the average particle size is preferably 0.5 μm or more, more preferably 1 μm or more, even more preferably 5 μm or more, even more preferably 10 μm or more, even more preferably 30 μm or more from the point of view of processing and the average particle size is preferably 300 μm or less, more preferably 200 μm or less, even more preferably 100 μm or less from the point of view of granulation.

A method of bringing the average particle size of potassium metaphosphate to the indicated limits includes a method comprising the step of processing the powdering of potassium metaphosphate using a known grinding mechanism, such as a fine grinding mill (atomizer), available from Fuji Paudal Co., Ltd, Pin Mill, available for purchase from Hosokawa Micron Corporation, and a turbine mill, available for purchase from TURBO KOGYO CO., LTD.

Solubilizing agent

Potassium metaphosphate is extremely difficult to dissolve in water, but exhibits solubility in water in the presence of a solubilizing substance. The solubilizing substance, as described, refers to a compound containing a source of sodium ions and / or a source of lithium ions and / or a source of ammonium ions, moreover, the sources can replace potassium in potassium metaphosphate. Therefore, in the detergent composition using the above creamy softening improving agent containing potassium metaphosphate together with the solubilizing agent, the potassium metaphosphate dissolves even when the detergent composition is dissolved in water, so that the washing liquid becomes a lotion-like viscous solution, whereby such benefits like slipping between items to be washed, and hand washing is improved.

The above solubilizing substance includes all of these ion sources — and / or lithium ion sources and / or ammonium ion sources, which replace potassium in potassium metaphosphate. Even more suitable solubilizing agents are inorganic salts and organic salts of sodium, lithium or ammonium, including, for example, sodium carbonate, sodium chloride, sodium sulfate, sodium sulfite, sodium carboxylates such as sodium citrate, sodium phosphate, sodium silicate, polycarboxylic sodium salts acids, sodium salts of polysulfonic acids, lithium halides and lithium sulfate. Among them, inorganic salts and organic sodium salts are even more preferred. In addition, the salt form of a surfactant or fatty acid, a metal ion scavenger or the like can also serve as a solubilizing agent.

Since the above potassium metaphosphate exhibits solubility in water when replacing potassium ion in potassium metaphosphate with sodium ion and / or lithium ion and / or ammonium ion, it is desirable to use potassium metaphosphate in a state in which it can be dissolved in order to obtain excellent handwash possibilities . Although some effects can only occur if part of the potassium in potassium metaphosphate can be replaced, it is preferable that the amount of solubilizing substance be such that it can provide sodium ions and / or lithium ions, and / or ammonium ions in an amount that can completely replace potassium ions in potassium metaphosphate contained in the washing liquid in terms of economic benefits. The amount of solubilizing agent is preferably 0.5 equivalents or more, more preferably 1 equivalent or more, even more preferably 2 equivalents or more, even more preferably 3 equivalents or more, when the amount that sodium ions and / or lithium ions can provide, and / or ammonium ions in the same amount as the amount of potassium ions in potassium metaphosphate, which is defined as 1 equivalent. On the other hand, in the presence of an excess of sodium ions and / or lithium ions and / or ammonium ions with respect to potassium ions, the effect of improving the possibilities for hand washing is negligible. From this point of view, the amount of solubilizing substance is preferably 400 equivalents or less, more preferably 200 equivalents or less, even more preferably 100 equivalents or less. In addition, the amount of solubilizing agent is preferably 30 equivalents or less, more preferably 20 equivalents or less from the point of view of still maintaining the effect of improving smoothness.

In this regard, when the required amount of sodium ions and / or lithium ions and / or ammonium ions are included in the detergent composition for other purposes, there is no need to separately add a solubilizing substance to the detergent composition.

3. Surfactant and / or main component

The detergent composition of the present invention may contain a surfactant and / or a main component.

As a surfactant, you can use those that are usually used for detergents. Surfactants include, for example, anionic surfactants and nonionic surfactants. Examples of the surfactant include anionic surfactants such as alkylbenzenesulfonates, alkyl ether or alkenyl ether sulfates, alkyl or alkenyl esters of sulfuric acid, α-olefin sulfonates, alkanesulfonates, N-acylamino acid-type surfactants, alkyl alkylethers amine acid-type surfactants, alkyl and alkenyl phosphoric esters or their salts; and nonionic surfactants, such as polyoxyalkylene alkyl (or alkenyl) ethers, polyoxyethylene alkyl phenyl ethers, higher fatty acid alkanolamides or alkylene oxide adducts, sucrose fatty acid esters, alkyl glycosides and glycerol fatty acid monoesters.

Among them, alkylbenzenesulfonates, alkyl ether sulfates, alkyl esters of sulfuric acid are preferred, and alkylbenzenesulfonates are even more preferred from the viewpoint of enhancing the smoothness effect.

The content of the above anionic surfactant and nonionic surfactant is preferably 5% by weight or more, more preferably 10% by weight or more, even more preferably 12% by weight or more, even more preferably 15% by weight or more , even more preferably 17% by weight or more of the detergent composition in terms of washing. In addition, the content of the above anionic surfactant and nonionic surfactant is preferably 40% by weight or less, more preferably 35% by weight or less, even more preferably 30% by weight or less, even more preferably 26% by weight or less of the detergent composition in terms of powder properties.

In the detergent composition of the present invention, a surfactant such as an amphoteric surfactant of the betaine type, a phosphoric acid ester surfactant, soap or a cationic surfactant in an appropriate amount may additionally be included in the composition.

The main component includes trapping metal ions, alkalizing agents, anti-scale agents and the like.

Among other things, since there is a characteristic property of reducing the effect of improving smoothness (softness) while increasing the amount of water hardness increasing component in the washing liquid, it is very effective to include a metal ion binding substance as a main component in the detergent composition and to capture the hardness increasing component in washing liquid for the manifestation of the properties of potassium metaphosphate. And, in addition, these metal ion binders having the ability to capture calcium ions of 100 mg CaCO ₃ / g or more are more effective. A metal ion binding agent includes ion exchange materials such as zeolites and crystalline silicates; water-soluble organic substances, such as polymers, such as polyacrylates and copolymers of acrylic acid-maleic acid (salt); and chelating agents such as sodium tripolyphosphate, ethylenediaminetetraacetates, methyl glycine diacetates and citrates.

Potassium metaphosphate, sodium carbonate and amorphous sodium silicate are not included in metal ion capture agents.

The alkylating agent includes carbonates and silicates. Amorphous sodium silicate is preferred in terms of increasing the effect of smoothness (softness).

Anti-scale agent includes carboxymethyl cellulose, polyethylene glycols and the like.

The amount of the main component in the formulation is preferably 5% by weight or more, more preferably 10% by weight or more, even more preferably 15% by weight or more, even more preferably 20% by weight or more of the detergent composition in terms of improving the possibilities of manual washing. In addition, the amount of the main component included in the formulation is preferably 60% by weight or less, more preferably 40% by weight or less, even more preferably 30% by weight or less of the detergent composition in terms of the balance of the formulation.

Silicates and phosphates (excluding potassium metaphosphate)

The detergent composition of the present invention may contain silicate or phosphate, whereby an advantage is given that the effects of improving smoothness (softness) can be further enhanced.

As silicates, amorphous and crystalline silicates are known, and any of them can be used. Those silicates that have a molar ratio of SiO ₂ / M ₂ O, where M is an alkali metal, preferably equal to 1 or more, more preferably 1.5 or more, even more preferably 2 or more, and silicates having a molar ratio of SiO ₂ are desirable / M ₂ O, preferably equal to 4 or less, more preferably 3 or less. Amorphous silicates are even more preferred here, and sodium silicate JIS No. 1 or sodium silicate JIS No. 2 can be used accordingly. The amount of silicate in the formulation is preferably 3% by weight or more, more preferably 5% by weight or more, more preferably 15% by weight or more, even more preferably 7% by weight or more of the detergent composition in terms of improving handwash capabilities . In addition, the amount of silicate included in the formulation is preferably 30% by weight or less, more preferably 20% by weight or less of the detergent composition from the point of view of suppressing the formation of insoluble residues during washing while maintaining the smoothness improvement effect ( softness) at a high level.

The phosphate includes sodium tripolyphosphate, sodium pyrophosphate, sodium dihydrogen phosphate, sodium hydrogen phosphate sodium phosphate and the like, and tripolyphosphate is preferred. The amount of phosphate in the formulation is preferably 5% by weight or more, more preferably 10% by weight or more, even more preferably 15% by weight or more of the detergent composition in terms of improving handwash capabilities. Furthermore, the amount of phosphate included in the formulation is preferably 40% by weight or less, more preferably 30% by weight or less of the detergent composition in terms of satisfying both the effect of improving smoothness (softness) and washing ability.

In the present invention, among the above components, since the metal-ion-trapping substance, silicate and phosphate are included in the amounts mentioned above, there is an advantage in that the possibility for hand washing is excellently maintained even when the amount of potassium metaphosphate in the formulation is reduced.

Other additives

In the detergent composition of the present invention, the composition may include an enzyme, perfume, phosphor, pigment and the like in an appropriate amount.

A method of obtaining a detergent composition

The detergent composition of the present invention having a composition as defined above can be obtained by appropriately mixing each of the above components in a known manner.

In this regard, since the potassium metaphosphate contained in the detergent composition of the present invention exhibits solubility in water in the presence of a solubilizing agent in water, as described above, it is preferable to reduce the water content during the preparation process and during storage. For example, when a detergent composition is prepared by spray drying, it is desirable to add a creamy smoothness (softness) improving agent and / or granules of a creamy smoothness (softness) improving agent in a granulation step, a surface modification step, and after a mixing step or the like after a spray drying step .

When added when the washing liquid is obtained by separately adding a detergent composition containing components other than a creamy smoothing (softness) improving agent during hand washing, a creamy smoothing (softening) improving agent, it is preferable to use a mixture of potassium metaphosphate with other agents as a creamy improving smoothness (softness) of the product in order to suppress the formation of a pasty mass upon dissolution.

In addition, a creamy smoothness (softness) improving agent and / or granules of a creamy smoothness (softness) improving agent and / or a detergent composition may contain a solubilizing agent, so that it is not necessary that the solubilizing agent is contained in the detergent composition.

Examples of the detergent composition include those detergent compositions that are formulated according to the method described in Tokkyocho Koho: Shuchi Kanyo Gijutsu Shu (Clothes Powder Detergent: Japanese Patent Office), 10 (1998) -25 (7159).

Washing method

The washing method of the present invention is a process comprising the step of performing a hand wash at a potassium metaphosphate concentration in water of 30 mg / L or more and a liquid ratio of 2 or more. This method includes, for example, a process comprising the steps of adding potassium metaphosphate to the washing liquid as part of the washing components or separately from the washing components and conducting a hand wash and the like.

Specific embodiments include a method comprising the step of adding the aforementioned creamy smoothness improving agent to a washing liquid as part of a detergent component or separately from a detergent component and performing a hand wash.

In this invention, since the concentration of potassium metaphosphate in water and the ratio of the liquid are brought to specific intervals, which are mentioned above, some advantages are that the washing liquid becomes a lotion-like liquid, so that an improvement in smoothness, softness between items to be washed is felt. and that the solubility of potassium metaphosphate and its adsorption on the surface of items to be washed is accelerated with increasing liquid ratio, so that an improvement in smoothness between etami to be washed.

The concentration of potassium metaphosphate in water is preferably 15 mg / L or more, more preferably 30 mg / L or more, more preferably 60 mg / L or more from the point of view of improving smoothness (softness). In addition, the concentration of potassium metaphosphate is preferably 3000 mg / L or less, more preferably 1500 mg / L or less, more preferably 1000 mg / L or less from the point of view of ease of handling of the items to be washed after washing. In addition, it is preferable that the concentration of potassium metaphosphate in water increases in accordance with a decrease in the liquid ratio, an increase in the rigidity of the washing liquid, an increase in the amount of non-ionic surfactant, an increase in the ratio of the amount of non-ionic surfactant and all components of the surfactants of the detergent composition facilities.

In addition, the ratio of liquid, which is the weight ratio of water to laundry, is preferably 2 or more, more preferably 3 or more, more preferably 4 or more, even more preferably 5 or more from the point of view of solubility and adsorption on items to be washed. The liquid ratio is preferably 20 or less, more preferably 15 or less in terms of ease of hand washing.

When using the washing method of the present invention having the constituents described above, effects such as smoothness are manifested, which are enhanced when the laundry to be rubbed against each other during hand washing, and washing that can be carried out with reduced force and the degree of friction of the laundry items against each other (the number of friction moments per unit time) is enhanced, so that the sensations during hand washing are improved, thereby achieving a gentle effect on the hands. Furthermore, by using the washing method of the present invention, it is possible to avoid damage to the fabric by increasing the smoothness (softness) between the fibers with respect to damage to the fibers that cause them to lose shape due to mechanical stress, such as stirring in the washing machine, as well as hand washing, whereby so-called “gentle washing effects” may occur.

EXAMPLES

In the following examples, embodiments of the present invention are further described and shown. The examples are presented for illustrative purposes only and should not be construed as limitations of the present invention.

Methods for determining properties in the examples will be described below.

<Viscosity Determination Method>

Two grams of potassium metaphosphate was added to 50 ml of water and the mixture was stirred for 1 minute. Then, a solution obtained by adding 4 g of sodium tripolyphosphate (manufactured by Shimonoseki Mitsui Chemicals, Inc.) to 50 ml of water was added to the mixture, the resulting mixture was stirred for 3 hours. The viscosity of the resulting mixture was determined at 25 ° C using a B-type viscometer.

<Determination of Na Content>

The 0.1-gth sample was dissolved in water and 4 ml of an aqueous HCl solution (1: 1) was added thereto, bringing the total volume to 50 ml. The Na content in the sample was determined using this solution using an atomic absorption spectrophotometer (available for purchase from VARIAN, Atomic Absorption Spectrometer Spectra AA220).

<Determination of AS Content>

The 5th sample was dissolved in water, and 4 ml of an aqueous HCl solution (1: 1) was added thereto, bringing the total volume to 50 ml. The As content in the sample was determined using this solution using an inductively coupled plasma emission spectrometer (available for purchase from HORIBA JOBINYVON, JY238ULTRAACE).

<Method for determining the molar ratio To / P>

The 0.1-gth sample was placed in a platinum crucible, in addition, 5 g of Li ₂ В ₄ О _{7 was} added thereto and an additional 0.5 g of a bleaching agent was added (Li ₂ СО ₃ : LiВr: LiNО ₃ = 5: 1 : 1 by weight). The mixture was melted at 1230 ° C. using a bead sampler (available for purchase from Tokyo Kagaku KK, NT-2100) to give glass beads.

K and P in glass beads were determined using a fluorescence X-ray analyzer (available for purchase from Rigaku Corporation, ZSX100e) under the following conditions (RF intensity):

X-ray Source: Rh Tube

Voltage, electric current: 50 kV, 50 mA

Spectral crystal Detector Angle -K: LiF SC (scintillation counter) 135.68 degrees -R: Ge RS (proportional counter) 141.19 degrees

Calculation of the K / P molar ratio was done by obtaining values for KH ₂ PO ₄ (available for purchase from Sigma-Aldrich Japan KK, a special reagent grade) in the same way as for the samples, and calculating the molar ratio of the samples according to the following formula using the molar ratio K / P equal to 1.00 as a standard:

The molar ratio K / P =

[RF intensity K (sample) x RF intensity R (reagent) /

[RF intensity P (sample) x RF intensity K (reagent)

<Handwash Evaluation Method>

Hand Wash Conditions

In 8.2 L polypropylene wash basin (manufactured by YAZAKI), having a diameter of 30 cm and a depth of 13 cm, 2 L of hard water (molar ratio Ca / Mg: 7/3) was charged, corresponding to 89.3 mg CaCO ₃ / liter, temperature maintained at 25 ° and the detergent composition was weighed so as to add 8.48 g to the water, and the water was continued to vigorously mix by hand so that the water did not pour out of the basin. After 30 seconds from the start of mixing, the T-blouse from 100% cotton (white, made by Gunze, size L) was soaked in washing liquid in the wash basin so that the entire T-blouse was sufficiently moistened. Then the front parts of the T-blouse were taken with both hands from the wrong side of the T-blouse and the front parts of the T-blouse were rubbed against each other. These parts rubbed against each other, removing the blouse from the washing liquid. After rubbing against each other for each part 3-5 times, the frayed parts were temporarily immersed in the washing liquid. Lightness during friction, when the parts were rubbed together, were evaluated for smoothness (softness) by a rank from 1 to 5. When the evaluation was made only with water prepared as described above, the folds on the blouse interfered with smoothness, the parts that needed to be rubbed together friend, it is almost unbelievable to rub, as there are no bubbles in the parts that need to be rubbed against each other, so that the smoothness deteriorates.

In this case, smoothness is defined as having a rating of 1. The state at each rating is as follows.

Grade 1: Very low smoothness and some creakiness, which makes it very difficult to do hand washing.

Grade 2: Low smoothness and a slight creakiness feeling, which makes it difficult to do a hand wash.

Grade 3: smoothness at an average level; hand wash without creaking is possible.

Grade 4: smoothness is high, handwashing is possible easily, without creaking.

Grade 5: smoothness is very high, it is possible to hand wash very easily, without creaking.

In this regard, in the test presented above, the average value of the results of the assessment by 6 participants is obtained in order to give an assessment.

(Example 1)

Obtaining potassium metaphosphate

The amount of 28.8 g of the raw material KH ₂ PO ₄ , including Na and As in the amount indicated in table 1, was dissolved in 360 g of water after the ion exchanger. Then, 0.488 g of H ₃ PO ₄ (commercially available from Wako Pure Chemical Industries, Ltd., special grade reagent, purity 85%) was added to the solution so that the K / P ratio was 0.98, and the mixture was stirred. The resulting mixed solution was spray dried using a spray dryer (available from TOKYO RIKAKIKAI CO., LTD., “Spray Dryer Model SD-1000”) to obtain a powder. Ten grams of the obtained powder was placed in an alumina crucible and burned at 700 ° C. for 3 hours. The resulting product was turned into a powder in a mill to obtain each of the potassium metaphosphate powders containing Na and As in the amount shown in Table 1 (1-1 to 1-10). The results of determining the viscosity of these potassium metaphosphates are presented in table 1.

(2) The amount of 370 kg of water for the preparation of the detergent composition, 200 kg of 50% by weight of an aqueous solution of dodecylbenzenesulfonate, 50 kg of 40% by weight of an aqueous solution of No silicate. 2, 100 kg of sodium carbonate, 147.5 kg of sodium sulfate, 5 kg of polyethylene glycol, 2.5 kg of CBS phosphor and 125 kg of zeolite were mixed together to obtain a homogeneous thick suspension. Then, the resulting thick suspension was spray dried to obtain a powder. The amount of 0.48 g of potassium metaphosphate (1-1 to 1-10) prepared in the manner described above was mixed with 8 g of the obtained powder to obtain a detergent composition. We evaluated this detergent composition for hand washing. The results are presented in table 1.

(Comparative example 1)

Each of the potassium metaphosphate preparations (1-1 to 1-6) was prepared in the same manner as in Example 1 using the raw material KH ₂ PO ₄ containing Na and As in the amount shown in Table 2, to obtain each of detergent compositions. The results of determining the viscosity of potassium metaphosphate and the evaluation results of the detergent composition for hand washing are presented in table 2.

Table 1 Example 1 The content of the raw material (KN ₂ RO ₄ ) (mmol / kg) Potassium metaphosphate content (mmol / kg) K / P ratio in potassium metaphosphate Potassium metaphosphate viscosity (MPa · sec) Hand Wash Results Evaluation As (OSE) Na (ITU) As (OSE) Na (ITU) 1-1 0 0 0 0 0.97 660 5 1-2 0 0 0 0 0.98 497 four 1-3 0.01 7 0.02 8.02 0.97 660 5 1-4 0 15.7 0 18.05 0.99 704 5 1-5 0 18.3 0 21.05 0.99 704 5 1-6 0.01 32.6 0.02 37.6 0.98 660 5 1-7 0.06 65,2 0,07 75,2 one 268 3 1-8 0.43 41.7 0.49 48.13 0.98 326 3,5 1-9 0.43 52,2 0.49 60.16 1.01 268 3 1-10 0.41 47.8 0.48 55.14 one 296 3

table 2 Comp. example 1 The content of the raw material (KN ₂ RO ₄ ) (mmol / kg) Potassium metaphosphate content (mmol / kg) K / P ratio in potassium metaphosphate Potassium metaphosphate viscosity (MPa · sec) Hand Wash Results As (OSE) Na (ITU) As (OSE) Na (ITU) 1-1 0.67 56.5 0.77 65,2 one 94 2 1-2 0.85 52,2 0.98 60,2 0.99 129 2 1-3 0.57 95.7 0.66 110.3 1,02 111 2 1-4 0.68 134.8 0.78 155.4 0.98 129 2 1-5 0.64 139.1 0.74 160,4 0.97 195 2.5 1-6 0.57 152.2 0.66 175.5 0.99 94 1,5

From the comparison between Example 1 and Comparative Example 1, it can be seen that when the content of Na modifying the element network and potassium metaphosphate is from 0 to 100 mmol and the content of As forming the element network is from 0 to 0.7 mmol, and the detergent composition They have high viscosity and excellent hand wash results.

(Example 2)

Potassium metaphosphate without Na and As content (K / P ratio: 0.98) was obtained in the same manner as in Example 1 using KH ₂ PO ₄ (commercially available from Sigma-Aldrich Japan KK, special reagent grade) without Na and As to obtain a detergent composition. Then, the viscosity determination and hand wash assessment were carried out in the same manner as in Example 1. As a result, the viscosity was 450 mPa · s, and the results of the hand wash assessment were ranked as 4.

(Example 3)

The amount of KH ₂ PO ₄ in 28.8 g (available for purchase from Sigma-Aldrich Japan KK, a special reagent grade) without the content of Na and As was dissolved in 360 g of water after the ion exchanger. To the solution was added CaCl ₂ (available for purchase from Wako Pure Chemical Industries, Ltd., a special reagent grade) in an amount of 0.0066 g, and then 0.488 g of H ₃ PO ₄ (available for purchase from Wako Pure Chemical Industries, Ltd., special reagent grade, purity: 85%) so as to bring the K / P ratio to 0.98, and the mixture was mixed. This solution was spray dried and burned in the same manner as in Example 1 to obtain potassium metaphosphate having a Ca content modifying the element network of 83 mmol (K / P ratio: 0.98). Then, a detergent composition was obtained. The viscosity of potassium metaphosphate was 630 MPa · s, and the results of the evaluation for hand washing were ranked as 5.

(Example 4)

An amount of KH ₂ PO ₄ (available for purchase from Sigma-Aldrich Japan KK, a special reagent grade) in 28.8 g without Na and As was placed in an alumina crucible. H ₃ PO ₄ (commercially available from Wako Pure Chemical Industries, Ltd., special reagent grade, purity: 85%) was added dropwise to the crucible so that the K / P ratio was 0.98 and the mixture was mixed. The mixture was burned and pulverized in the same manner as in Example 1 to give potassium metaphosphate without Na and As (K / P ratio: 0.98). Then, a detergent composition was obtained.

The viscosity determination and evaluation for handwashing were carried out in the same manner as in Example 1. As a result, the viscosity was 250 mPa · s, and the results of evaluation for handwashing were ranked as 3.

When the potassium metaphosphate in this example was compared with the potassium metaphosphate in example 2, which was obtained by spray drying a mixed aqueous solution of raw materials, the mixing was unsatisfactory, the viscosity was low, and the results of evaluation by hand washing were slightly worse.

In addition, when comparing the potassium metaphosphates from examples 3 and 4, potassium metaphosphate containing 83 mmol of a network-modifying element (example 3) gave more favorable evaluation results for hand washing.

When hand washing in examples 1 to 4, rough skin on the hands was not observed, which thereby shows an excellent hand-protecting action. We evaluated the condition of T-blouses after hand washing from examples 1 to 4. As a result, it can be seen that frayed fibers and the like did not appear in any of the examples, which shows an excellent protective effect on the fabric.

The present invention, which is described in this way, as will be apparent, may vary in many ways. Such changes should not be construed as a departure from the essence and scope of the present invention, and all such modifications, as should be obvious to a person skilled in the art, are intended to be included in the scope of the following claims.

Claims (13)

1. Creamy improving the smoothness (softness) of the laundry when washing the product containing potassium metaphosphate, having a viscosity in an aqueous solution of 200 MPa · s or more, and the viscosity is determined under the following conditions: with the addition of 2 g of potassium metaphosphate to 50 ml of water, mixing mixture for 1 min, adding a solution obtained by dissolving 4 g of sodium tripolyphosphate to 50 ml of water, stirring the mixture for 3 hours and determining the viscosity in a B-type viscometer at 25 ° C, where the specified potassium metaphosphate contains, in addition to phosphorus, arsenic in number of TBE from 0 to 0.7 mmol to 1 kg of potassium metaphosphate, and in addition potassium, sodium in an amount of from 0 to 100 mmol per 1 kg of potassium metaphosphate. 2. The creamy laundry smoothing enhancing agent according to claim 1, wherein the potassium metaphosphate is obtained by spray drying from an aqueous solution of potassium dihydrogen phosphate and phosphoric acid or an aqueous solution of potassium dihydrogen phosphate, phosphoric acid, arsenic and / or sodium, and firing the spray dried product. 3. The creamy smoothness improving laundry detergent according to claim 1, wherein the creamy smoothness improving laundry washing is used for hand washing. 4. A detergent composition containing a creamy laundry-improving smoothing agent according to any one of claims 1 to 3 and a solubilizing agent. 5. The detergent composition according to claim 4, where the detergent composition is a detergent detergent. 6. The detergent composition according to claim 4, wherein the solubilizing agent comprises an ion source for substitution in an amount of at least 0.5 equivalent of potassium ion in potassium metaphosphate. 7. The detergent composition according to claim 4, further comprising a surfactant and / or a main component. 8. The detergent composition according to claim 4, additionally containing as a main component a metal ion-capturing substance having the ability to capture calcium ions of 100 mg CaCO ₃ / g or more, in an amount of 5% by weight or more. 9. The detergent composition of claim 8, where the substance that captures metal ions is a water-soluble organic substance. 10. The detergent composition according to claim 4, further comprising silicate. 11. The detergent composition according to claim 4, further comprising phosphate. 12. A method of hand washing, in which washing is carried out under conditions of a concentration of potassium metaphosphate, as defined in any one of claims 1 to 3, in water equal to 30 mg / l or more and a weight ratio of water to items of laundry equal to 2 or more. 13. A method for producing potassium metaphosphate as defined in claim 1, comprising the step of spray drying an aqueous solution of potassium dihydrogen phosphate and phosphoric acid or an aqueous solution of potassium dihydrogen phosphate, phosphoric acid, arsenic and / or sodium, and firing the spray dried product.