JP2024057315A - Time-release flavoring agent - Google Patents

Abstract

[Problem] When toilet paper rolls are actually used, there are many cases where the scent is either still slightly present or has completely disappeared. [Solution] Focusing on cellulose nanofibers (CNF), the odor components constituting the fragrance are retained in the fine mesh formed by the cellulose nanofibers, and furthermore, by using a hydrophilic emulsifier in combination, a situation is created in which the odor components are stably retained for a long period of time, and a sustained-release fragrance has been created. The fragrance composition in which the fragrance is dissolved in an oil-based solvent, cellulose nanofibers, and a hydrophilic emulsifier are included, with the remainder being water and auxiliary agents blended as necessary, and is in the form of an emulsion formulation. The sustained-release fragrance can be applied to the surface of the paper product by spray painting, and then simply dried, so no special equipment is required and it is suitable for application to paper products sold at low prices, such as toilet paper rolls. [Selected Figure] None

Description

The present invention relates to a sustained release fragrance that imparts a fragrance to paper products.

Paper products such as toilet paper rolls and gift envelopes are sometimes given appropriate fragrances depending on the situation of use in order to differentiate them from competitors' products.
However, the scent gradually fades, so when toilet paper rolls are stored for a relatively long period of time, there are often only a few traces of scent remaining or the scent has completely faded by the time the roll is placed in the toilet holder and used.

JP 2019-108562 A

In response to this, Patent Document 1 proposes encapsulating the fragrance in a resin capsule, but this requires special equipment, and it is not cost-effective to apply this to inexpensive paper products such as toilet paper rolls.

The present invention was made with a focus on the above-mentioned problems of the conventional art. The inventors focused on cellulose nanofibers (CNF) and discovered that the odor components that make up the fragrance are retained in the fine mesh formed by these cellulose nanofibers, and further discovered that the combined use of a hydrophilic emulsifier creates a situation in which the odor components are stably retained for a long period of time, which led to the completion of the present invention.

The present invention is a sustained-release fragrance for paper products in emulsion form, which comprises a fragrance composition in which a fragrance is dissolved in an oily solvent, cellulose nanofibers, and a hydrophilic emulsifier, with the remainder being water and auxiliary agents which are blended as necessary.
Preferably, the cellulose nanofibers have an average fiber length of 55±20 μm and an average fiber width of 50±20 nm.
Preferably, the perfume of the perfume composition comprises galaxolide.

In the method for producing the sustained-release fragrance of the present invention, the fragrance composition is preferably mixed with a hydrophilic emulsifier, and then mixed with an aqueous dispersion of cellulose nanofiber and, if necessary, water.

The method of using the sustained-release fragrance of the present invention is preferably to apply the sustained-release fragrance to the surface of the paper product by spray coating, and then to dry it.

The sustained-release fragrance of the present invention can impart a fragrance to a paper product simply by applying it to the surface of the paper product by spray coating.
In the manufacturing process of core-equipped toilet paper rolls, a step of applying the sustained-release fragrance of the present invention to the paper core after the paper core is formed is added, so that toilet paper rolls with a long-lasting fragrance can be manufactured without the need for dedicated complex and costly equipment, while continuing to use conventional manufacturing equipment as is.

FIG. 1 is a comparative diagram showing the fibrillation of cellulose nanofibers used in the present invention. FIG. 2 is an image diagram of the mechanism of fragrance imparted by the sustained-release fragrance of the present invention. FIG. 1 is a comparative diagram of emulsion stability verified in the emulsion verification (1) performed in the Examples. FIG. 1 is a comparative diagram of emulsion stability verified in the emulsion verification (2) performed in the Examples. FIG. 1 is a comparative diagram of emulsion stability verified in the emulsion verification (3) performed in the Examples. 1 is a comparative graph of the sensory evaluation carried out in the examples. 1 is a comparative graph of GC/MC evaluation carried out in the examples. 1 is a comparative graph of the sensory evaluation of product samples carried out in the examples.

The sustained-release flavoring agent of the present invention will be explained in terms of its composition, manufacturing method, and method of use.

<Composition of sustained release flavoring agent>
[Fragrance composition]
Fragrances include natural fragrances and synthetic fragrances, both of which can be used. However, natural fragrances include water-soluble fragrances and oil-soluble fragrances, the former of which are fragrances extracted or dissolved in aqueous alcohol, and since they are highly volatile and tend to lose their scent, the latter natural essential oils or fragrances dissolved in oil are assumed to be used in the paper products of the present invention. Fragrances also include emulsified fragrances, which are oil-soluble fragrances emulsified and dispersed in water, and these are also assumed to be used in the present invention.

In addition, since it is used to add fragrance to disposable paper products, it can be used for things other than those that go into the human mouth, and from a cost perspective, its use in this way is actively encouraged. Since most paper products are unscented, the purpose is to add a fragrance, and fragrances are selected according to that purpose.
A variety of fragrance compositions in which a fragrance is dissolved in an oily solvent are already commercially available as fragrances, and it is possible to purchase one from these, taking into consideration cost and the type of scent that suits the product image, and use it as the "fragrance composition in which a fragrance is dissolved in an oily solvent" of the present invention.

Representative examples of toilet freshener scents include "elegant bouquet" and "jasmine," and it has been confirmed in the following examples that these are useful as the "sustained-release fragrance" of the present invention. However, "elegant bouquet" and "jasmine" are classified by scent, and the composition of the odor components that make them up is not uniquely determined, and there are some differences between manufacturers.
Of the odor components that make up fragrances, experiments have shown that galaxolide is easily retained and may have a positive effect on the persistence of fragrance, and it is therefore recommended that fragrances containing galaxolide be used.

[Cellulose nanofiber (CNF)]
Cellulose nanofibers (hereinafter referred to as "CNF") are single microfibrils of cellulose obtained by defibrating a cellulose-based raw material, and for retaining odor components, preferably have an average fiber length of 55±20 μm and an average fiber width of 50±20 nm. The average fiber length of CNF was obtained by measuring using a particle size distribution diameter measurement, and the average fiber width was obtained from the results of observing each fiber using an atomic force microscope (AFM, field of view: 10 μm).
In an experiment, rough defibration (clearance: 500 μm) → fine defibration (clearance: 150 μm, 3 to 5 passes) was carried out, and the fibrillated material and commercially available CNF were measured, with the results shown in Table 1 below. The progress of fibrillation was as shown in the photograph in Figure 1.

In the manufacturing stage of the sustained-release fragrance, CNF is used in the form of an aqueous dispersion. The final CNF concentration can be adjusted by adding water, and is appropriately adjusted taking into consideration not only the expression of significant properties as a sustained-release fragrance, but also the ease of mixing with the fragrance composition and ease of processing when applied to paper products, for example, the viscosity suitable for spraying when spray coating.

[Hydrophilic emulsifier]
The fragrance composition is the oil phase and the CNF is the aqueous phase, and a hydrophilic emulsifier (surfactant) is used in combination to aid in emulsification of these.
A wide variety of hydrophilic emulsifiers are commercially available, and one that is compatible with the flavor composition constituting the oil phase is appropriately selected and used.
Hydrophilic emulsifiers include PEG-30 hydrogenated castor oil, which is a polyethylene glycol ether of hydrogenated castor oil with an average number of moles of ethylene oxide added of 30. It has been experimentally confirmed that it is compatible with the above-mentioned "Elegant Bouquet" and "Jasmine."
If necessary, it is permitted to add auxiliary substances within a range that does not impair the properties as a sustained-release flavoring agent that are originally required.

[Formulation]
The hydrophilic emulsifier is classified on the aqueous phase side, and preferably, the oil phase (fragrance composition + auxiliary agent if necessary): aqueous phase (CNF dispersion + hydrophilic emulsifier + water if necessary) = 30-70 wt %: 70-30 wt %.
The preferred range of CNF concentration is determined not only by the ease of retention of the odor components that make up the fragrance, but also by the ease of work in the process of applying it to paper products. For example, when spray painting using a spray gun, it is necessary to lower the viscosity to a certain level so that it can be sprayed. When using commercially available fragrances, the preferred range is about 0.3 to 0.5 wt%.
The preferred range of the hydrophilic emulsifier is about 3 to 5 wt %.

<Method of manufacturing sustained release flavoring agent>
Make it into an emulsion formulation.
Preferably, the fragrance composition and the hydrophilic emulsifier are mixed together and stirred to be uniform, and then the CNF dispersion is added and further stirred to emulsify into an emulsion formulation. The stirring is carried out with a homogenizer.
If all the ingredients are mixed together and emulsified at once, the emulsion may not be stable depending on the type of fragrance. However, by first mixing the fragrance composition with a hydrophilic emulsifier, the emulsion can be stabilized regardless of the type of fragrance.

<Method of use of sustained release flavoring agent>
The sustained-release flavoring agent in emulsion form is applied to the surface of the paper product by spraying with a spray gun, and then dried at room temperature.
When it is desired to add fragrance to a toilet paper roll, a sustained release fragrance is applied to a paper core for a small roll of toilet paper according to the product specifications, the core is dried, and then paper is rewound onto the core from a jumbo roll produced on a papermaking machine.

Next, the mechanism of fragrance imparted by the sustained-release fragrance applied to the surface of the paper product will be described.
As shown in the image diagram in Figure 2, in the product of the present invention (CNF fragrance), the odor molecules (= odor components) that make up the fragrance are surrounded by a hydrophilic emulsifier, and then CNF covers them like a net to form a CNF network.
The CNF network adheres not only to odor molecules but also to the surrounding hydrophilic emulsifier, and the adhesion at multiple points distorts the mesh, creating locally narrow areas. Therefore, it is not easy for odor molecules to escape from the distorted mesh of the CNF network. In other words, the odor molecules are in a state as if they are trapped in the CNF network. Therefore, the sustained release effect is high.

On the other hand, in the case of <Blank>, where the odor molecules are simply applied to the surface of the paper product and dried, the odor molecules can easily fly away, so as time passes, the odor molecules fly out from the surface and are diffused into the surroundings. Therefore, there is no sustained release effect.
In addition, in the case of (fragrance → CNF), where odor molecules are applied and then covered with a CNF network, the odor molecules tend to escape from the CNF network, so the retention effect of the CNF network is insufficient, and the sustained release effect is therefore low.

<Emulsion verification (1) (without hydrophilic emulsifier)>
The mixture was weighed ([total amount] 5,000 g (CNF concentration: 0.75 wt%), [composition] fragrance composition: 50 wt%, CNF dispersion (CNF concentration: 1.5 wt%): 50 wt%) and emulsified by stirring with a homogenizer for 5 minutes. The mixture was then allowed to stand at room temperature for 3 days and the separation state of the emulsion formulation was evaluated by visual observation with the following criteria: ○: stable, △: slight separation, ×: separation. Note that 3-pass and 5-pass CNF shown in Figure 1 were used.
The results are shown in Figure 3 along with a photograph. The area enclosed by the dotted line is where separation was observed.
As the fibrillation of CNF progresses, the stable period of emulsion can be extended somewhat, but it has been confirmed that fibrillation alone is not enough to extend the period to a level that is suitable for practical use.

<Emulsion verification (2) (hydrophilic emulsifier added)>
The mixture was weighed ([total amount] 5,000 g, [composition] fragrance composition: 50 wt %, CNF dispersion + hydrophilic emulsifier: 50 wt %, further details as shown in Table 2 below), emulsified by stirring for 5 minutes with a homogenizer, and then left to stand for 5 days in a 40°C environment (approximately 1 month in room temperature equivalent), and evaluated in the same manner as in Emulsion Verification (1).

The results are shown in FIG.
By mixing a CNF concentration of approximately 0.5 wt % and a hydrophilic emulsifier of approximately 4 wt %, that is, by appropriately adjusting the CNF concentration and the hydrophilic emulsifier concentration, the stable period of the emulsion can be extended, but it has been confirmed that, depending on the type of fragrance, there is still room for further improvement before it can withstand practical use.

<Emulsion verification (3) (hydrophilic emulsifier added + stirring conditions changed)>
Jasmine Sample 4 from Emulsion Verification (2) was used as Sample 1 this time, and the stirring conditions were further changed so that the fragrance composition and hydrophilic emulsifier were combined and stirred in a homogenizer for 5 minutes, and then the CNF dispersion was added and stirred in a homogenizer for 5 minutes to emulsify. This was used as Sample 2, and was tested in the same manner as Emulsion Verification (1).

The results are shown in FIG.
It has been confirmed that by adopting these special stirring conditions, the hydrophilic emulsifier works well and the emulsion stability period is uniformly extended to a practical level, regardless of differences in fragrance.

<Sensory evaluation>
The core paper for a toilet paper roll was cut to an appropriate size, and the samples shown in Table 3 below were applied onto it using a pipette. The samples were then left to stand in a 45°C environment for one week or four weeks (room temperature equivalent: one week -> approximately nine months, four weeks -> approximately 36 months), and the fragrance strength was compared and evaluated.
The evaluation was based on a six-level odor intensity rating system (0: no odor, 1: barely detectable odor, 2: weak odor that is identifiable, 3: easily detectable odor, 4: strong odor, 5: overwhelming odor).

In Table 3, <Elegant Bouquet> samples 2 and 4 correspond to samples 2 and 4 in Table 2 relating to emulsion verification (2), and sample 3 differs from samples 2 and 4 in Table 2 only in the CNF concentration. Sample 1 is composed of only the fragrance composition, and sample 5 is composed of the fragrance composition and then the CNF dispersion. The <Jasmine> sample was prepared in the same way as the <Elegant Bouquet> sample.

The results are shown in FIG.
It is presumed that the cooperative action of CNF and hydrophilic emulsifier realizes the mechanism shown in the image in Figure 2, which actually produces the sustained release effect.

<GC/MS evaluation>
For the <Elegant Bouquet> samples 1, 4, and 5 in Table 3, the addition amounts were 5 μL, 10 μL, and 10 μL, respectively, and the samples were left in a 45°C environment for 1 hour, 5 hours, and 4 weeks (room temperature equivalent: 4 weeks → approximately 36 months), and quantitative analysis was performed using GC/MS.
The target odor components were selected from the following three types that were smelled particularly strongly prior to measurement:
- Linalool (RT: 10.9 min): floral - Coumarin (RT: 16.2 min): floral - Galaxolide (RT: 21.1 min): sweet scent For the evaluation, the increase or decrease in the odor components from 1 to 5 hours was compared, and the area values of the odor components after 4 weeks were compared.

The results are shown in FIG.
It has been confirmed that the synergistic action of CNF and hydrophilic emulsifier reduces the amount of odor components emitted, i.e., the amount of volatilization.
In addition, it was confirmed that the area values were generally higher than those of galaxolide at CNF 0.5 in particular due to the synergistic effect of CNF and hydrophilic emulsifiers. From this, it is inferred that the retention effect of CNF is quite effective for galaxolide.

<Commercialized as toilet paper rolls>
The paper core was treated with a CNF fragrance equivalent to that of Elegant Bouquet sample 4 in Table 3. For comparison, a Blank without CNF was also prepared.
From this paper core, toilet paper rolls were produced using actual production equipment.
This toilet paper roll was subjected to a sensory evaluation in the same manner as above.
The samples were left standing in a 45°C environment for one day, one week, and two weeks.

The results are shown in FIG.
After two weeks had passed, the CNF fragrance corresponding to Elegant Bouquet sample 4 in Table 3 showed a significant sustained release effect, confirming that the product has desirable quality.

The above describes in detail the embodiments and examples of the present invention, but the scope of the present invention is not limited to these, and design changes that do not deviate from the gist of the present invention are also included in the invention.

Claims (6)

A sustained-release fragrance for paper products in emulsion form, comprising a fragrance composition in which a fragrance is dissolved in an oil-based solvent, cellulose nanofibers, and a hydrophilic emulsifier, with the remainder being water and auxiliary agents blended as necessary. 2. The sustained release flavoring agent according to claim 1,
A sustained-release fragrance agent characterized in that the cellulose nanofibers have an average fiber length of 55±20 μm and an average fiber width of 50±20 nm. 3. The sustained release flavoring agent according to claim 1 or 2,
A sustained-release fragrance excipient, characterized in that the fragrance of the fragrance composition contains galaxolide. The method for producing the sustained-release flavoring agent according to claim 1,
A production method characterized by mixing a fragrance composition with a hydrophilic emulsifier, and then mixing with an aqueous dispersion of cellulose nanofibers and, if necessary, adding water. A method for using the sustained release flavoring agent according to claim 1,
A method of use comprising spray-coating a sustained-release fragrance onto the surface of a paper product and then drying the same. A toilet paper roll having a paper core covered with a sustained-release fragrance by the method of using the sustained-release fragrance described in claim 5.

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