JP5571538B2 - Deodorization effect confirmation method - Google Patents

Description

  The present invention relates to a method for confirming the deodorizing effect of a chemical deodorant that can confirm the deodorizing effect of a deodorant by a color change.

  When determining the deodorizing effect of a deodorant or the like against bad odors, particularly fatty acid odors, sensory evaluation or evaluation by instrumental analysis is generally employed. However, when an unfamiliar evaluator performs sensory evaluation, the evaluator's subjective judgment may be entered. Moreover, since the amount of fatty acids is very small, instrumental analysis requires an analytical instrument such as gas chromatography, and is not a simple method.

  Therefore, there is a demand for a method capable of confirming the deodorizing effect by a simple method. For example, Patent Document 1 confirms the deodorizing effect of a fiber structure such as clothing using a reagent containing an odor-forming substance and a pH indicator.

  On the other hand, several methods for visually confirming the presence or absence of malodor are known. For example, Patent Document 2 discloses a bad breath check method in which saliva and test liquid are mixed in a container, and an odorous gas generated is detected by an ammonia detector containing a pH indicator.

JP 2010-112841 JP 2007-248329 A

  However, in the case of fatty acid malodor, as in Patent Document 1, when trying to confirm the effect of a deodorant with a reagent containing a malodor-forming substance and a pH indicator, the pH indicator is sufficiently colored due to the low solubility of fatty acids. There was a case not to. In addition, even when the fatty acid dissolves to a concentration at which the pH indicator sufficiently develops color, when the intensity of the odor is judged by the change in color of the indicator and when the expert panel actually judges by sensory evaluation Differences sometimes occurred.

  Therefore, an object of the present invention is to provide a deodorizing effect confirmation method that can confirm the deodorizing effect of a deodorant by a color change and that prevents deviation from sensory evaluation by a specialized panelist.

  The present inventors, together with a fatty acid as a malodorous component and a pH indicator, coexisting an acid for pH adjustment in a specific ratio, the color change showing a deodorizing effect is consistent with the sensory evaluation of a specialized panelist, It was found that the deodorizing effect of chemical deodorization with high reliability can be confirmed.

The present invention provides a deodorizing effect confirmation method for contacting a deodorant with an odor confirmation reagent containing the following components (A) to (C) and confirming the deodorizing effect by a color change before and after the contact. Is.
(A) C2-C12 fatty acid optionally having a hydroxyl group 0.005-0.6% by mass
(B) Protonic acid at a concentration that gives a proton concentration of 5.0 × 10 ^{-2 to} 0.05 × 10 ^-2 mol / L in a state in which all protons are dissociated in the odor confirmation reagent (one corresponding to component (A) except)
(C) pH indicator

Furthermore, the present invention provides a deodorizing effect confirmation kit comprising a odor confirmation reagent containing the following components (A) to (C) and a sheet.
(A) C2-C12 fatty acid optionally having a hydroxyl group 0.005-0.6% by mass
(B) Protonic acid at a concentration that gives a proton concentration of 5.0 × 10 ^{-2 to} 0.05 × 10 ^-2 mol / L in a state in which all protons are dissociated in the odor confirmation reagent (one corresponding to component (A) except)
(C) pH indicator

  ADVANTAGE OF THE INVENTION According to this invention, the deodorizing effect confirmation method which can confirm the deodorizing effect of a deodorizer by the change of a color, and also does not produce a shift | offset | difference with sensory evaluation is provided.

[Odor confirmation reagent]
The fatty acid having 2 to 12 carbon atoms which may have a hydroxyl group as component (A) is a body odor, sweat odor, habit odor, foot odor, freshly dried odor, indoor dried odor, tobacco odor, fecal odor, pet odor, elderly It is a model offensive odor component that is an object of evaluation such as a stained odor in a room. The fatty acid of component (A) may be linear or branched, and may be either saturated or unsaturated. Specifically, acetic acid, propionic acid, butyric acid (butyric acid), valeric acid (valeric acid) ), Isovaleric acid, hexanoic acid, heptanoic acid, octanoic acid, nonanoic acid, decanoic acid, dodecanoic acid, 3-hydroxy-3-methylhexanoic acid, 3-methyl-2-hexenoic acid, 4-methylhexenoic acid It is done. Of these, acetic acid, propionic acid, valeric acid (valeric acid), isovaleric acid, hexanoic acid, heptanoic acid are components that are detected when instrumental analysis of body odor is performed from the viewpoint of confirming the deodorizing effect on body odor. , Octanoic acid, nonanoic acid, and decanoic acid are preferable, and isovaleric acid and hexanoic acid are particularly preferable.

  The content of component (A) in the reagent for confirming odor is sufficient for sensory evaluation, and in the range of 0.005 to 0.6% by mass from the viewpoint that the sensory evaluation result matches the color change. However, 0.005 to 0.5 mass%, more preferably 0.01 to 0.1 mass% is preferable.

  The protonic acid of component (B) functions as a pH adjuster in order to match the change in color showing the deodorizing effect and the sensory evaluation in the odor confirmation reagent, and other than the fatty acid of component (A) Is used. From the viewpoint of influence on sensory evaluation, the proton acid of component (B) is preferably one having a weak odor strength, particularly odorless, in the concentration contained in the odor confirmation reagent. Specifically, a protonic acid having an odor intensity of 0 according to a 6-step odor intensity display method (bad odor prevention method) by a specialized panel when dissolved in a solvent at the above concentration is preferable. Here, the expert panelist means a person who has been particularly trained to measure odor.

Specific examples of such a protic acid having an odor intensity of 0 include the following acids.
(1) Phosphoric acid compounds such as phosphoric acid, tripolyphosphoric acid, phytic acid (inosinic acid) (2) ethylenediaminediacetic acid, hydroxyethyliminodiacetic acid, iminodiacetic acid, nitrilotriacetic acid, ethylenediaminetetraacetic acid, diethylenetriaminepentaacetic acid, Aminopolycarboxylic acid compounds such as glycol ether diamine tetraacetic acid, triethylenetetramine hexaacetic acid, ethylenediamine disuccinic acid, iminodisuccinic acid and hydroxyiminodisuccinic acid (3) amino acids such as aspartic acid and glutamic acid (4) maleic acid, phthalate Acid, terephthalic acid, isophthalic acid, fumaric acid, oxalic acid, succinic acid, malonic acid, glutaric acid, adipic acid, azelaic acid, diglycolic acid, oxydisuccinic acid, carboxymethyloxysuccinic acid, glycolic acid, citric acid, lactic acid, Mandel , Malic acid, citric acid, glyceric acid (2,3-dihydroxy propanoic acid), tartaric acid, diacetyltartaric acid, gluconic acid, heptonic acid, carboxymethyl succinic acid, carboxymethyl acid or tartaric acid

  Of these, a protonic acid having a pKa of 3.5 to 5.5 is preferable, and a protonic acid having a pKa of 4.0 to 5.0 is more preferable from the viewpoint of the color development stability of the pH indicator. Furthermore, polyvalent carboxylic acid is more preferable. Of these, succinic acid, citric acid, malic acid, tartaric acid, oxalic acid, maleic acid, fumaric acid and glutaric acid are more preferred, and succinic acid, fumaric acid, citric acid and malic acid are particularly preferred.

The concentration of component (B) is 5.0 × 10 ^{−2 to} 0.05 × 10 ⁻² mol / L in terms of proton concentration in the state where protons are completely dissociated in the odor confirmation reagent, and 2.5 × 10 ^{− 2 to} 0.05 × 10 ⁻² mol / L is more preferable, and 1.0 × 10 ^{−2 to} 0.05 × 10 ⁻² mol / L is particularly preferable.

  The mass ratio of the component (A) and the component (B) is preferably within a certain range from the viewpoint of matching the sensory evaluation result with the change in color, but is more preferably within the range depending on the detection threshold of the component (A). Is different. For example, when the component (A) is a protonic acid having a detection threshold of 0.00015 to 0.008 ppm, such as hexanoic acid, heptanoic acid, butyric acid, acetic acid, propionic acid, etc. The mass ratio of A) to component (B) is preferably 1: 0.05 to 1: 3, more preferably 1: 0.08 to 1: 1.5. On the other hand, component (A) is isovaleric acid, valeric acid (valeric acid), octanoic acid, nonanoic acid, decanoic acid, dodecanoic acid, 3-hydroxy-3-methylhexanoic acid, 3-methyl-2-hexenoic acid, 4 In the case of a protonic acid having a detection threshold of 0.000005 to 0.00008 ppm, such as -methylhexenoic acid, the mass ratio of component (A) to component (B) is preferably 1: 0.5 to 1:30, and 1: 0.8 to 1: 15 is more preferred.

  As the pH indicator of component (C), those having a color change range in the acidic range are preferable, those having a color change range in pH 3 to 7, particularly those having a color change range in pH 4 to 6 are preferable. As such an indicator, for example, methyl yellow (2.9 to 4.0), bromophenol blue (3.0 to 4.6), Congo red (3.0 to 5.0), methyl orange (3.1 to 4.4), bromocresol green (3.8 to 5.4), Examples include methyl red (4.4 to 6.2), litmus (4.5 to 8.3), and bromocresol purple (5.2 to 6.8). Congo red, bromocresol green, methyl red, and litmus are preferred, and congo red and methyl red are particularly preferred. (The values in parentheses indicate the color change range pH).

  The content of the component (C) in the odor confirmation reagent is preferably 0.001 to 1.0% by mass, more preferably 0.002 to 0.5% by mass, particularly from the viewpoint of easily confirming the color change due to the deodorizing effect. 0.005-0.2 mass% is preferable.

  As the solvent for the odor confirmation reagent, in order not to affect the sensory evaluation, those having low odor intensity, particularly those having no odor are preferred, and water is most preferred, but the solubility of the components (A) and (C) In consideration of this, a mixed solvent of water and ethanol may be used. When using a mixed solvent of water and ethanol, the mass ratio of water and ethanol is preferably 1: 0.02 to 1: 3.

[Deodorization effect confirmation method / deodorization effect confirmation kit]
The deodorizing effect can be confirmed by bringing a deodorant into contact with the odor confirming reagent and changing the odor intensity before and after the reagent by changing the color. At this time, if sensory evaluation is also performed, it is possible to confirm by the olfaction the coincidence with the deodorizing effect indicated by the color change.

  The specific evaluation system may be any mode as long as the odor confirmation reagent and the deodorant can be mixed, and the odor confirmation reagent is mixed with the odor confirmation reagent in the container to change the odor intensity. However, from the viewpoint of ease of sensory evaluation, the odor confirmation reagent is dropped or sprayed on the sheet, and then the deodorant is dropped on the area where the odor confirmation reagent is dropped or sprayed. Or the method of spraying is preferable.

  Moreover, if it provides as a form of the deodorizing effect confirmation kit which consists of the said odor confirmation reagent and a sheet | seat suitable for using in the above methods, it is useful as an easy deodorizing effect confirmation means. A preferred embodiment of such a kit for confirming the deodorization effect includes a sheet for confirming the deodorization effect comprising a sheet impregnated with a reagent for confirming the odor in advance.

  As the sheet, any sheet may be used, but a sheet having the same color as the color at the time of neutralization (deodorization) of the pH indicator is preferable from the viewpoint of easily confirming the color change visually. For example, when methyl red is used as an indicator, it is preferable that the sheet is also yellow because it changes to yellow when neutralized. As a result, when a bad odor occurs, the odor confirmation reagent is colored red, but when it is deodorized by the deodorant, it becomes the same yellow color as the sheet, so at the same time the odor confirmation reagent disappears. Looks like. In the case of Congo red, the sheet is preferably reddish for the same reason because it changes to red during neutralization.

The yellow color here is a color having an a value of -5 to +35, a b value of +30 to +60, and an L value of 70 to 80 in the L * a * b * color system defined by JIS Z 8729. It shall be said. The red color means a color having an a value of +25 to +60, a b value of −10 to +40, and an L value of 20 to 80 in the L * a * b * color system.

  As the material of the sheet, any sheet may be used as long as it has water absorption enough to hold the reagent for confirming odor. However, woven fabric, knitted fabric, paper, etc. that are not subjected to water repellent treatment are preferable, and contain synthetic fibers. Non-raised fabrics are more preferred, and polyester fabrics are particularly preferred.

Examples 1-11, Comparative Examples 1-6
Add 20 μL of odor confirmation reagent shown in Tables 1 to 3 (mixture of fatty acid (hexanoic acid or isovaleric acid), citric acid, methyl red and water) shown in Tables 1 to 3 to a cloth (100% polyester, yellow) Then, the odor intensity (sensory evaluation with 6-step odor intensity) and the coloring on the cloth (visual evaluation) were evaluated.
Next, after adding 0.5 mL of deodorant to the area where the reagent of the cloth is dropped, the odor strength (sensory evaluation by the specialized panelist with 6-step odor intensity) and the color change (visual evaluation) on the cloth are evaluated. did. In addition, the time until the entire sheet became the same color as the sheet (color change time) was also measured.

<Odor intensity evaluation criteria>
0: Odorless 1: Smell that can be finally detected 2: Weak odor that shows what odor is 3: Smell that can be easily detected 4: Strong odor 5: Strong odor

<Visual evaluation>
・ Before dropping deodorant ◎: Clear dark red ○: Slightly deep red △: Slightly red ×: Slightly yellowish red (close to the color of the sheet)
・ After deodorant was added ○: Red color did not remain and the whole color became yellow (same color as the sheet)
Δ: A little red remains ×: Most red remains

Examples 12-13, Comparative Example 7
On a cloth (100% polyester, red), add 20 μL of the deodorant confirmation reagent shown in Table 4 (mixed solution of fatty acids (hexanoic acid or isovaleric acid), citric acid, Congo red and water) of component (A). The odor intensity (sensory evaluation with 6-level odor intensity by a specialized panelist) and the coloration (visual evaluation) on the cloth were evaluated.
Subsequently, after adding 0.5 mL of deodorizer to the area where the reagent of the cloth was dropped, the odor intensity (sensory evaluation with 6-step odor intensity) and the color change (visual evaluation) on the cloth were evaluated. In addition, the time until the entire sheet became the same color as the sheet (color change time) was also measured.

<Odor intensity evaluation criteria>
Same as above <Visual evaluation>
・ Before dropping the deodorant ◎: Vivid dark blue-purple ○: Slightly deep blue-purple △: Slightly blue-purple ×: Slightly reddish-purple (close to the color of the sheet)
・ After deodorant dropping ○: Blue purple is not left and the whole is red (same color as the sheet)
Δ: A little blue-purple remained ×: Almost blue-purple remained

Claims (9)

Deodorizing effect confirmation method of contacting the deodorant with a reagent for odor confirmation containing the following components (A) to (C) in water or water / ethanol, and confirming the deodorizing effect by color change before and after contact. .
(A) Model malodor component selected from hexanoic acid and isovaleric acid 0.005-0.6 mass%
(B) Citric acid at a concentration that gives a proton concentration of 5.0 x 10 ^{-2 to} 0.05 x 10 ^-2 mol / L when all protons are dissociated in the odor confirmation reagent
(C) pH indicator whose color change range is between pH 3-7 The deodorizing effect confirmation method according to claim 1, wherein the component (A) is hexanoic acid , and the mass ratio of the component (A) and the component (B) is 1: 0.05 to 1: 3. The method for confirming a deodorizing effect according to claim 1, wherein the component (A) is isovaleric acid and the mass ratio of the component (A) to the component (B) is 1: 0.5 to 1:30. The deodorizing effect confirmation method according to any one of claims 1 to 3 , wherein the deodorizing effect on body odor is confirmed. The method for confirming the deodorization effect according to any one of claims 1 to 4, wherein a reagent for odor confirmation is dropped or sprayed on a sheet, and then a deodorant is dropped or sprayed on the dropped or sprayed portion. The method for confirming the deodorizing effect according to claim 5 , wherein the color of the sheet is the same as that of the neutral pH indicator. The method for confirming the deodorizing effect according to claim 6 , wherein the pH indicator is methyl red and the color of the sheet is yellow. The method for confirming the deodorizing effect according to claim 6 , wherein the pH indicator is Congo red and the color of the sheet is red. A kit for confirming the deodorization effect comprising a reagent for odor confirmation containing the following components (A) to (C) in water or water / ethanol and a sheet.
(A) Model malodor component selected from hexanoic acid and isovaleric acid 0.005-0.6 mass%
(B) Citric acid at a concentration that gives a proton concentration of 5.0 x 10 ^{-2 to} 0.05 x 10 ^-2 mol / L when all protons are dissociated in the odor confirmation reagent
(C) pH indicator whose color change range is between pH 3-7