Substrates treated with solutions containing cyclodextrins to impart odor eliminating properties to materials used in absorbent products

Abstract

A solution containing cyclodextrin that imparts odor-eliminating properties to materials used in absorbent products, and related products and methods. The solution containing cyclodextrin that imparts odor-eliminating properties to materials used in absorbent products includes an optional polar organic solvent, water, cyclodextrin, and one or more odor-eliminating compounds. The solution can be used to uniformly apply a homogenous solution of cyclodextrin complexes onto a solid surface, which precipitates the cyclodextrin complexes in situ on the solid surface. The precipitates of cyclodextrin complexes deposited from these solutions quickly release odor-masking scents when hydrated with urine, and can be deposited on substrates more effectively than solid forms of cyclodextrin complexes.

Description

[Technical field]

[0001] The present disclosure relates to solutions comprising cyclodextrins that impart odor-eliminating properties to materials used in absorbent products, substrates treated with solutions comprising cyclodextrins that impart odor-eliminating properties to materials used in absorbent products, and related products and methods. [Background technology]

[0002] The odor of fresh urine should be eliminated in a short amount of time by absorbent products such as adult incontinence liners, incontinence pads, diapers, pull-up underwear, and the like. Such products are often disposable products worn in public. Their users place great importance on odor control to avoid potential embarrassment. Although many of the commercial products claim to provide some type of odor control, these commercial products may not be effective at eliminating the odor of fresh urine the moment the product is used. The odor of fresh urine at body temperature is often detectable in these absorbent products. Urine from elderly people may be especially noticeable. Thus, the industry remains desirous of more effective odor control, especially in absorbent products.

[0003] Many attempts have been made to solve the problems associated with odor reduction in absorbent products. In some of the major approaches, odor reduction requires inhibiting the growth of odor-causing bacteria and adsorbing odor molecules onto high surface area adsorbents. However, such conventional techniques are generally too slow and / or ineffective in reducing the odor of fresh urine in a short amount of time.

[0004] Another approach uses cyclodextrin for deodorizing absorbent products. For example, US Pat. No. 5,399,433 discloses the use of free, uncomplexed cyclodextrin to effectively absorb malodors. In US Pat. No. 5,399,433, cyclodextrin is used to increase the surface area available for absorbing odor molecules, thus improving odor absorption efficiency. US Pat. No. 5,399,433 also teaches perfume / cyclodextrin complexes formed by either combining perfume and cyclodextrin in a suitable solvent, such as water, or preferably by kneading and / or slurrying the ingredients together in the presence of a minimal amount of solvent, preferably water. The kneading / slurrying method is particularly desirable because it results in smaller solid particle sizes. After freeze-drying or spray-drying, the solid complex may be ground into particles having a particle size of less than about 10 μm. However, care must be taken during grinding to avoid creating workplace safety hazards due to respirable particles.

[0005] Furthermore, for example, Patent Document 2 describes the use of aqueous odor absorbing solutions for use on odorous surfaces. The composition of the solution disclosed in Patent Document 2 includes about 0.1% to about 20% of a solubilized, water-soluble, non-complexed cyclodextrin, an effective amount of at least one component that improves the odor absorbing performance of the cyclodextrin, and a water-soluble antimicrobial active. These solutions are typically provided in a spray dispenser and are commercialized under the trade name FEBREZE®.

[0006] Although the prior art provides cyclodextrins that can be used to absorb odors in general, it is not easy to incorporate fine dry particles of cyclodextrin complexes into absorbent articles. Dry complex powders can be sprinkled, mixed, or distributed into absorbent products. However, in practice, these application methods have not been satisfactory. The immobilization of cyclodextrin / fragrance complexes should not involve excessive amounts of water to avoid premature release of fragrance. Water-soluble binders, such as low melting polymeric binders such as polyethylene glycol, have been disclosed. Another method disclosed involves applying cyclodextrin / fragrance slurries directly to absorbent products, plus a drying step. However, in practice, these slurries are difficult to handle, dispense, and apply uniformly.

[0007] Patent Document 3 teaches an absorbent article comprising an inclusion complex of cyclodextrin and an organic compound made using a process of colloid milling and spray drying to produce a cyclodextrin complex in the form of a low viscosity liquid that can be more easily handled during the manufacture of the absorbent article and to avoid settling of the insoluble cyclodextrin particles, the inclusion complex being dispersed in a matrix containing a polysiloxane oil. The production of dry particles of colloidal dimensions allows the production of a homogeneous dispersion of solid particles used in the construction of the absorbent article.

[0008] In US Pat. No. 5,399,513, examples are given in which cyclodextrin is applied to kraft cellulose fibers by dissolving it in water at elevated temperatures to form a clear solution and spraying the solution onto the fibers. All examples require the carrier water to be dried from the substrate, either by air or oven drying, or freeze drying. Due to the low solubility of cyclodextrin, a large amount of additional solution is required to achieve an effective level of performance, and due to the high water content of the solution, drying of the cellulose fibers is required to prevent microbial growth during storage. Fluff pulp typically contains 6% to 8% water after drying. When the moisture content increases to the range of about 13% to 15%, microbial growth can occur. Therefore, all these examples are not practical without an additional drying step.

[0009] US Patent No. 5,399,633 also teaches the use of an effective amount of a cyclodextrin / active complex in the form of solid particles having a particle size of less than about 12 μm to rapidly release a perfume active upon wetting. Handling these solid particles is simple in fabric softener and solid detergent compositions, but can be cumbersome and problematic when attempting to apply the solid particles to absorbent materials and / or absorbent products.

[0010] Patent Documents 5 and 6 claim a layer of an absorbent article treated with a substituted cyclodextrin complex (i.e., degree of substitution = R of 0.4 to 2.5 per glucose unit of cyclodextrin) and a deodorizing organic compound in powder form or dispersed in a carrier to form a dispersion that is applied to the absorbent article. The carrier was polysiloxane oil, mineral oil, petrolatum, polyethylene glycol, and / or glycerin. Patent Documents 5 and 6 also describe an application method using cyclodextrin and a deodorizing organic compound in a volatile solvent system containing at least 60% water, alcohol, ketone or aldehyde, hydrocarbon, or supercritical fluid. In some forms, the solution can be easily pumped or sprayed directly onto the absorbent article. However, in this approach, only substituted cyclodextrins are used, which are believed to stack upon crystallization into a physical form that is superior to unsubstituted cyclodextrins for rapid release of the deodorising compounds complexed with the cyclodextrin.

[0011] Patent Document 7 teaches a method of making an odor-suppressing absorbent fiber pulp sheet, which comprises a cyclodextrin odor absorbent and a biocide dissolved in a non-aqueous liquid carrier consisting of less than 20% water, and which is applied to a cellulose fiber pulp sheet. Many of the fragrances and essential oils, such as citral, included in this disclosure have been shown to have biocidal activity, as listed in the following disclosures: Non-Patent Document 1, Non-Patent Document 2, and Non-Patent Document 3.

[0012] While odors can be reduced using the above referenced applications and prior art, there remains a need for a convenient method to eliminate the odor of fresh urine in absorbent products at the moment of use. That is, many of the previous approaches to odor elimination act too slowly to reduce the odor of fresh urine in the product at the moment of use and / or require additional processing, resulting in additional costs. The present inventors have solved the problems associated with the previous approaches and provide a solution that is effective in reducing the odor of fresh urine in a very short amount of time. Users of these products place a high value on odor resistance to avoid potential embarrassment. The present disclosure provides a method to achieve these and other objectives by making a solution containing a relatively high concentration of cyclodextrin complex that can be easily spray applied to materials used in absorbent products without the need for a drying step, as will be discussed in detail below. The moisture gain of the treated absorbent material should be less than 1% by weight, let alone less than 5% by weight, without the use of a drying step. [Prior art documents] [Patent documents]

[0013] [Patent Document 1] U.S. Patent No. 5,429,628 [Patent Document 2] U.S. Patent No. 6,284,231 [Patent Document 3] U.S. Patent No. 9,592,168 [Patent Document 4] U.S. Patent No. 5,571,782 [Patent Document 5] U.S. Patent No. 10,183,273 [Patent Document 6] U.S. Patent No. 10,427,133 [Patent Document 7] U.S. Patent No. 8,574,683 [Non-patent literature]

[0014] [Non-Patent Document 1] K. Winska, et. al., "Essential Oils as Antimicrobial Agents-Myth or Real Alternative?" Molecules (2019) Jun; 24(11): 2130 [Non-Patent Document 2] C. Shi. et. al., "Antimicrobial Activity and Possible Mechanism of Action of Citral against Cronobacter sakazakii" PLoS One 2016; 11(7) [Non-Patent Document 3] "Lemongrass Essential Oil Components with Antimicrobial and Anticancer Activities" by M, Choudhary, et. al. Antioxidants 2021 Dec 22; 11(1): 20 Summary of the Invention

[0015] In view of the above-mentioned typical problems associated with the application of previously known cyclodextrins, the present application provides a new and improved solution comprising cyclodextrins that imparts odor-eliminating properties to materials used in absorbent products.

[0016] One embodiment of the present application is a substrate having a deodorizing solution applied thereto, the deodorizing solution comprising water, cyclodextrin, a deodorizing compound, and optionally a polar organic solvent, wherein the substrate comprises at least 0.2 kg of the deodorizing compound per 1000 kg of substrate, and wherein, as a result of applying the deodorizing solution onto the substrate, the substrate exhibits an increase in moisture content of less than 2% by weight.

[0017] In one embodiment of the above substrate, the deodorizing solution further comprises a stabilizing additive.

[0018] In one embodiment of any of the above substrates, the deodorizing solution comprises 1.5 mol to 6 mol of the deodorizing compound per mol of cyclodextrin.

[0019] In one embodiment of any of the above substrates, the deodorizing solution has a pH greater than 9 and less than 12.5.

[0020] In one embodiment of any of the above substrates, the deodorizing solution comprises about 6% to about 19% by weight of cyclodextrin and the deodorizing compound.

[0021] In one embodiment of any of the above substrates, the odor eliminating compound is selected from the group consisting of citral, coconut fragrance oil, d-limonene, octanol, and combinations thereof.

[0022] In one embodiment of any of the above substrates, upon application of the deodorizing solution onto the substrate, the substrate exhibits an increase in moisture content of less than 1.7% by weight.

[0023] In one embodiment of any of the above substrates, the deodorizing solution contains 3.5 mol to 4.5 mol of the deodorizing compound per 1 mol of cyclodextrin, and before applying the deodorizing solution to the substrate, the deodorizing solution is mixed at a temperature of 20°C or higher to form a dispersion containing a complex of cyclodextrin and the deodorizing compound.

[0024] In one embodiment of any of the above substrates, the deodorizing solution comprises about 0.1% to about 14% by weight of a stabilizing additive.

[0025] In one embodiment of any of the above substrates, the stabilizing additive is selected from the group consisting of corn syrup, glucose, high fructose corn syrup, trehalose, sucrose, sorbitol, amino acids, derivatives thereof, and combinations thereof.

[0026] In one embodiment of any of the above substrates, the stabilizing additive is selected from the group consisting of corn syrup, glucose, high fructose corn syrup, derivatives thereof, and combinations thereof, and the odor eliminating solution comprises about 2% to about 10% by weight of the stabilizing additive.

[0027] In one embodiment of any of the above substrates, the stabilizing additive is trehalose, and the deodorizing solution comprises about 0.1% to about 1.0% by weight of the stabilizing additive.

[0028] In one embodiment of any of the above substrates, the deodorizing solution further comprises glucose and / or corn syrup as a stabilizing additive, the deodorizing solution comprises about 2.4% to about 9.4% by weight of the stabilizing additive, the deodorizing solution comprises about 3.5 mol to about 6 mol of the deodorizing compound per mol of cyclodextrin, the deodorizing solution has a pH greater than 9 and less than 12.5, the deodorizing compound is a blend of compounds selected from the group consisting of a blend of citral and coconut fragrance oil, a blend of d-limonene and coconut fragrance oil, a blend of citral and d-limonene, and a blend of octanol and d-limonene, prior to applying the deodorizing solution to the substrate, the deodorizing solution is mixed at a temperature of 20° C. or greater to form a dispersion comprising a complex of the cyclodextrin and the deodorizing compound, and further, the application of the deodorizing solution onto the substrate results in the substrate exhibiting an increase in moisture content of less than 1.7% by weight.

[0029] One embodiment of the present application includes an article comprising any one of the substrate embodiments described above.

[0030] One embodiment of the present application includes a method for making a deodorizing substrate, the method comprising: a) preparing a substrate; b) forming a deodorizing solution comprising water, cyclodextrin, a deodorizing compound, a stabilizing additive, and optionally a polar organic solvent; wherein the deodorizing solution formed in b) is a dispersion comprising a complex of cyclodextrin and the deodorizing compound; c) applying the deodorizing solution onto the substrate to obtain a deodorizing substrate, wherein after c), the deodorizing substrate comprises at least 0.2 kg of the deodorizing compound per 1000 kg of the deodorizing substrate, and the substrate exhibits an increase in moisture content of less than 1.7% by weight as a result of applying the deodorizing solution onto the substrate.

[0031] Another embodiment of the present application is a substrate having a deodorizing solution applied thereto, the deodorizing solution comprising water, cyclodextrin, a deodorizing compound, and a polar organic solvent, wherein the substrate comprises at least 0.2 kg of the deodorizing compound per 1000 kg of substrate.

[0032] In one embodiment of the substrate, the substrate exhibits an increase in moisture content of less than 1% by weight as a result of application of the deodorizing solution onto the substrate.

[0033] In one embodiment of any of the above substrates, the substrate is fluff pulp in the form of compressed sheets or in the form of airlaid fibers, spunbonded or carded nonwovens of synthetic or cellulosic fibers, woven fabrics, or solid materials, or absorbent articles, where when the substrate is a solid material, the solid material is selected from the group consisting of polymer foams, leather, and plastic films, and the substrate material is an absorbent article, where the absorbent article is an adult incontinence pad, a feminine hygiene pad, a pull-up underwear, an adult brief, a baby diaper, or a bed pad.

[0034] In one embodiment of any of the above substrates, the polar organic solvent is selected from the group consisting of glycerol, propylene glycol, polypropylene glycol, polyethylene glycol, and mixtures thereof.

[0035] In one embodiment of any of the above substrates, the cyclodextrin is unsubstituted or substituted α-cyclodextrin, β-cyclodextrin, or γ-cyclodextrin.

[0036] In one embodiment of any of the above substrates, the deodorant compound is at least one of the following: an essential oil, plant extract, benzaldehyde, cinnamaldehyde, ligustral, florhydral, and mixtures thereof selected from the group consisting of citral, limonene, octanol, lavandin, geranium, grapefruit, linalool, citronellol, linalyl acetate, geraniol, eugenol, floracetate, cardamom, eucalyptus, juniper berry, lavender, lemon verbena, lemongrass, patchouli, rose, spearmint, tea tree, oregano, persimmon, and mixtures thereof; or an antimicrobial material selected from the group consisting of eucalyptus, lavender, thyme, peppermint, cajeput, cinnamon, clove, sage, tea tree oil, and mixtures thereof.

[0037] In one embodiment of any of the above substrates, the deodorizing solution comprises 1.5 mol to 1.75 mol of the deodorizing compound per 1 mol of cyclodextrin.

[0038] In one embodiment of any of the above substrates, the deodorizing solution has a pH of 12.0 or greater.

[0039] One embodiment of the present application includes an article comprising any one of the substrate embodiments described above.

[0040] One embodiment of the present application includes a method for making a deodorizing substrate, the method comprising: a) preparing a substrate; and b) applying a deodorizing solution onto the substrate to obtain a deodorizing substrate, wherein the deodorizing solution comprises a polar organic solvent, water, cyclodextrin, and a deodorizing compound, and after b), the deodorizing substrate comprises at least 0.2 kg of the deodorizing compound per 1000 kg of the deodorizing substrate.

[0041] In one embodiment of the above method, the application of the deodorizing solution onto the substrate in b) increases the moisture content of the substrate by less than 1% by weight.

[0042] In one embodiment of any of the above methods, the deodorizing solution comprises 1.5 mol to 1.75 mol of the deodorizing compound per mol of cyclodextrin.

[0043] In one embodiment of any of the above methods, the deodorizing solution has a pH of 12.0 or greater.

[0044] Other objects, features and advantages of the present invention will become apparent to those skilled in the art from a consideration of the following detailed description of the invention and the accompanying drawings.

[0045] The drawings provided herein show some exemplary embodiments of solutions containing cyclodextrins that impart odor-eliminating properties to materials used in the absorbent products of the present application, detailed descriptions of which follow: The drawings are illustrative only and are not intended to limit the invention. [Brief description of the drawings]

[0046] [Figure 1] 1 is a graph showing the amount and response of citral for urine deodorization. [Diagram 2] FIG. 20 is a micrograph at 20x with a minimum scale of 100 μm showing particles of citral / β-cyclodextrin complex precipitated from a glycerol / water solution at pH 12.5 and 86° C. [Diagram 3]FIG. 20 is a micrograph at 20x with a minimum scale of 100 μm showing particles of citral / β-cyclodextrin complex precipitated from a glycerol / water solution at pH 9.6 and 86° C. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0047] Next, a solution containing cyclodextrin that imparts odor-eliminating properties to materials used in absorbent products, as well as related products and methods of the present application, will be described with reference to embodiments. The description provided herein is not intended to limit the scope of the claims, but is intended to illustrate the variety encompassed by the present application. The embodiments will be described in more detail below with reference to the accompanying drawings, in which like numerals represent like elements throughout the figures and exemplary embodiments are shown. However, the claimed embodiments may be implemented in many different forms and should not be construed as being limited to the embodiments provided herein. The examples provided herein are non-limiting examples and are merely examples among other possible examples.

[0048] As discussed above, there is a need for technology that quickly removes fresh urine odor from absorbent products such as adult incontinence liners, incontinence pads, and pull-up underwear. Since such products are often disposable products worn in public, odor prevention is important to users to avoid potential embarrassment. Many of the products on the market claim some type of odor elimination, but these products may not be effective at eliminating the fresh urine odor the moment the product is used. The odor of fresh urine at body temperature may be easily detected in these absorbent products.

[0049] To solve the problems associated with the prior art, the present disclosure uses a fast-acting odor masking deodorant that can be incorporated into a cyclodextrin complex and deposited on fluff fibers. The active ingredient is stabilized in the complex over a long shelf life and is released only when the fiber comes into contact with urine. Many essential oil fragrances and organic deodorants can be used to create stable cyclodextrin complexes that are highly soluble in polar organic solvent and water solvent systems. These soluble complexes can be sprayed evenly onto a sheet of fluff fibers or applied in other ways. After cooling to room temperature, the complex is precipitated in situ on the fiber surface, resulting in an unexpectedly effective use of the odor masking agent, which exhibits excellent deodorant properties when the fiber is hydrated with urine. Thus, the present disclosure relates to novel solutions applied in specific add-on amounts that (1) have an optimal essential oil to cyclodextrin molar ratio and solution pH, (2) have a concentration of soluble cyclodextrin complexes sufficient to impart urine deodorizing properties when applied to materials used in absorbent products, and (3) have a low enough concentration of water so that no additional drying step is required after its application.

[0050] Cyclodextrins are cyclic oligosaccharides containing 6-12 glucose units that can form inclusion complexes with host molecules that can fit entirely or partially within the cyclodextrin cavity. Inclusion complexes composed of highly volatile essential oils and other deodorant ingredients can be deposited on the surface of a substrate in a stable dry form. A stable dry form is required because volatile essential oils are expensive components of the formulation and should not evaporate from the treated substrate. The scent of the host molecule, especially the essential oil, can be released by the action of water and urine. The present disclosure relates to solutions of favorable composition, pH, and temperature to create soluble complexes composed of cyclodextrin and essential oils or deodorant compounds, such that the solution containing the soluble complexes can be sprayed or otherwise applied to materials used in absorbent products, such that upon cooling to room temperature the complexes precipitate in situ on the surface of the material, and the complex-treated material reduces the odor of body fluids such as urine, menstrual fluids, and sweat.

[0051] Cyclodextrin complexes containing cyclodextrin and deodorant compounds tend to have low water solubility and can be difficult to apply and retain uniformly on the surface of solid fibers or films. A solution containing polar organic solvents and water provides the ability to form cyclodextrin complexes in solution at elevated pH and temperature, and also provide the solubility required to apply a homogeneous solution of cyclodextrin complexes uniformly on solid surfaces. Upon cooling to room temperature, the cyclodextrin complexes precipitate in situ on the solid fiber surface. Because the cyclodextrin complexes precipitate in situ on the solid fiber surface, no particle size control is required. Typically, the complexes are formed by mixing or kneading the deodorant compound and cyclodextrin together in the presence of a small amount of water. After freeze-drying or spray-drying, the complexes are milled to a particle size of less than about 10 μm. Such a process is not required because the solution disclosed herein utilizes in situ precipitation. Furthermore, no colloidal stabilization is required to create and apply the complexes. Thus, cyclodextrin complexes can be easily made and applied to absorbent and cellulosic materials without the need for a drying step.

[0052] A solution containing cyclodextrin that provides deodorizing properties The deodorizing solution of the present disclosure may include water, a cyclodextrin, a deodorizing compound, and optionally a polar organic solvent.

[0053] In certain embodiments, the polar organic solvent may be excluded from the deodorizing solution, while in other embodiments, the polar organic solvent may be included in the deodorizing solution. In embodiments in which the polar organic solvent is excluded from the deodorizing solution, the deodorizing solution may be primarily water. The amount of water may be, for example, in the range of 82% to 93% by weight based on the total weight of the deodorizing solution. In certain embodiments, the water may be in the range of 75% to 95% by weight, 80% to 95% by weight, 80% to 90% by weight, 82% to 93% by weight, or about 85% by weight, based on the total weight of the deodorizing solution, respectively. In embodiments that include a polar organic solvent, the amount of the polar organic solvent may be in the range of 4% to 10% by weight, 5% to 8% by weight, or about 6% to about 7% by weight, and the amount of water may be in the range of 5% to 15% by weight, 8% to 13% by weight, or about 11% to about 12% by weight, based on the total weight of the deodorizing solution, respectively.

[0054] The polar organic solvent can be any polar organic solvent that can provide the ability to form cyclodextrin complexes in solution and provide the solubility required for uniform application of a homogeneous solution of cyclodextrin complexes on a solid surface. Examples of acceptable polar organic solvents include, but are not limited to, glycerol, propylene glycol, polypropylene glycol, polyethylene glycol, and mixtures thereof. In particular, glycerol can be used as the polar organic solvent. Increasing the amount of polar organic solvent in the solution can increase the solubility of the cyclodextrin complexes in the solution. For example, the solubility of the complexes can be increased, so that an effective amount of the complexes can be applied to the substrate without excessively increasing the moisture. Table 1 below shows the increase in substrate moisture for two levels of addition (i.e., 0.4 kg essential oil per 1 ADMT fluff pulp and 2.0 kg essential oil per 1 ADMT fluff pulp) depending on the glycerol concentration.

[0055] [Table 1]

[0056] A higher addition of 2.0 kg citral per 1 ADMT fluff pulp, shown as 5 and 6 in Table 1, could not keep the moisture gain below 1% when the solution fraction of glycerol was much below 85%. In other embodiments, 100% carrier water is used, as in 3 and 6 shown in Table 1. A 100% aqueous solution containing a relatively high concentration of β-cyclodextrin at pH 12.5 can be made. Adding 1.5 mol of citral per mol of β-cyclodextrin can form a fine, sprayable dispersion, in this case where the concentration of the complex is about 19.7% or less. At higher concentrations of the complex, a coarse dispersion is formed. This coarse dispersion settles within a few minutes and is very difficult to spray onto a substrate.

[0057] The cyclodextrin can be any cyclodextrin capable of forming a cyclodextrin complex with a deodorising compound. In certain embodiments, the cyclodextrin is a cyclodextrin containing 6 to 12 glucose units. For example, a cyclodextrin containing 6 to 12 glucose units can form an inclusion complex with many essential oils and deodorising ingredients, where the essential oils and deodorising ingredients can be released by the action of water and urine. Examples of acceptable cyclodextrins include, but are not limited to, commercially available unsubstituted cyclodextrins (i.e., α-cyclodextrin, β-cyclodextrin, and γ-cyclodextrin). α-cyclodextrin contains 6 glucose units. β-cyclodextrin contains 7 glucose units. γ-cyclodextrin contains 8 glucose units. In particular, β-cyclodextrin may be used because it has an acceptable cost-performance ratio for use in most absorbent products.

[0058] As discussed above, the deodorizing solution can form a cyclodextrin complex with the deodorizing compound in the solution. Unsubstituted cyclodextrin can be used to make such a complex. Generally, three types of unsubstituted cyclodextrin are commercially available (i.e., α-cyclodextrin, β-cyclodextrin, and γ-cyclodextrin). Among these commercially available unsubstituted cyclodextrins, β-cyclodextrin has an acceptable cost-performance ratio for use in most absorbent products. The solubility of β-cyclodextrin in water at about 20° C. is only 1.8 g per 100 ml of water. However, the solubility of β-cyclodextrin is only 1.8 g per 100 ml of water at a pH (pK ) of 12.5. a = 12.2) to 75 g / ml at 20°C. The solubility of β-cyclodextrin in glycerol is 4.3 g / 100 ml at 20°C. As shown in Table 2, the solubility of β-cyclodextrin and β-cyclodextrin / citral complex in 85% / 15% glycerol / water solution at elevated pH and temperature is at a level of 21.6 g / 100 g solution or more. Propylene glycol can also be used to make the solution. The solubility of β-cyclodextrin is greater in propylene glycol than in glycerol. Therefore, the solubility of cyclodextrin and its complexes can be increased by using a polar organic solvent / water solution, increasing the temperature of the solution, and increasing the pH.

[0059] [Table 2]

[0060] Furthermore, substituted cyclodextrins have a higher water solubility than unsubstituted cyclodextrins, but the performance of unsubstituted cyclodextrins is still very good. Unsubstituted cyclodextrins can also be formulated into solutions at relatively high concentrations. Therefore, unsubstituted cyclodextrins can be used in the solutions of the present invention.

[0061] The deodorizing compound can be any deodorizing compound capable of providing deodorizing and / or odor-masking properties. Examples of acceptable deodorising compounds include, but are not limited to, essential oils such as citral, limonene, d-limonene, lavandin, geranium, persimmon, lemon, grapefruit, linalool, citronellol, linalyl acetate, geraniol, eugenol, floracetate, cardamom, eucalyptus, juniper berry, lavender, lemon verbena, lemongrass, patchouli, rose, spearmint, tea tree, oregano, and mixtures thereof; plant extracts such as Actiphyte™ by Lubrizol; deodorising substances such as benzaldehyde, cinnamaldehyde, ligustral, florhydral, and mixtures thereof; antimicrobial substances such as eucalyptus, lavender, thyme, peppermint, cajeput, cinnamine, clove, sage, tea tree oil, and fragrances such as coconut fragrance oil, and mixtures thereof. In particular, citral (i.e., C 10 H 16 O) can be used as a deodorizing compound. Citral is an essential oil with a strong lemongrass odor, which is effective in eradicating and / or masking urine odor. Other scented essential oils, particularly limonene and persimmon, reactive aldehydes, particularly benzaldehyde, and thio-reducing compounds, particularly florhydral and ligustral, and fatty alcohols such as octanol, may be effective, either alone or in combination. In certain embodiments, the deodorizing compound is a blend of compounds selected from the group consisting of a blend of citral and coconut fragrance oil, a blend of d-limonene and coconut fragrance oil, a blend of citral and d-limonene, and a blend of octanol and d-limonene.

[0062] The total amount of cyclodextrin and deodorant compound in the solution is limited by the solubility of the complex formed, typically in the range of about 22% by weight or less for a glycerol / water solution with a ratio of about 85 / 15. In certain embodiments, the amount of β-cyclodextrin / citral complex in the solution can be 15% to 22% by weight, 20% to 22% by weight, and / or about 21% by weight. In other embodiments, i.e., in the case of a 100% aqueous solution, the concentration of the complex can be lower, such as in the range of about 14% by weight or less or even 13.8% by weight or less, if fine precipitates are formed upon addition of citral to the β-cyclodextrin / water solution. In certain embodiments, the concentration of cyclodextrin and deodorant compound in the deodorant solution is in the range of about 6.4% to 13.8% by weight. The deodorizing solution may have a concentration of cyclodextrin and deodorizing compound in a range having an upper limit of 20%, 18%, 16%, 14%, 12%, 10%, 8%, or 6% by weight and a lower limit of 1%, 2%, 3%, 4%, 5%, 6%, 7%, or 8% by weight. In certain embodiments, the deodorizing solution comprises about 6% to about 19% by weight of cyclodextrin and deodorizing compound, or the deodorizing solution comprises about 6.4% to about 18.2% by weight of cyclodextrin and deodorizing compound. In other embodiments, the deodorizing solution comprises about 8% to about 9% by weight of cyclodextrin and deodorizing compound. At higher concentrations, such as concentrations above 20% by weight, undesirably coarse precipitates may form.

[0063] The solution concentration of the complex is important to reduce the amount of solution added to keep the moisture gain of the substrate below about 2% by weight, below about 1.7% by weight, below about 1.3% by weight, and / or below about 1% by weight. However, the ratio of deodorant compound to cyclodextrin is also important to impart good deodorant performance to the substrate. For citral, the optimal molar ratio of citral to β-cyclodextrin is about 1.5 mol to about 1.75 mol citral to 1.0 mol β-cyclodextrin. Below about a 1:1 molar ratio, the deodorant performance is significantly reduced (for an equal amount of citral added). Above a molar ratio of 1.75:1, the volatile uncomplexed citral imparts unwanted color and odor to the substrate for a solution containing about 85% glycerol. For solutions made without polar organic solvents, EO:CD molar ratios in the range of 4-6 allowed mixing at 50°C, and corn syrup was added at molar ratios in the range of 4-6 allowed mixing at 20°C. In general, the molar ratio of deodorizing compound to cyclodextrin can be, for example, 2.5:1, 2.25:1, 2.0:1, 1.75:1, 1.5:1, 1.4, 1.3, 1.2, 1.1, and 1.0. In certain embodiments, the molar ratio of deodorizing compound to cyclodextrin can be 6.0:1, 5.5:1, 5.0:1, 4.5:1, 4.0:1, 3.5:1, and 3.0:1. Also, in certain embodiments, the deodorizing solution contains 1.5 mol to 6 mol of deodorizing compound per mol of cyclodextrin. In another embodiment, the deodorizing solution comprises 3.5-4.5 mol of deodorizing compound per mol of cyclodextrin. Increasing the molar ratio of deodorizing compound to cyclodextrin may improve commercial processing, particularly but not limited to, by allowing lower solution mixing pH and lower mixing temperature for primarily water-based solutions.

[0064] A higher molar ratio of citral to β-cyclodextrin allows for the use of less glycerol and β-cyclodextrin to achieve the target citral loading (kg of citral per metric ton of air-dried fluff). This also reduces the moisture gain of the fluff pulp, as shown in Table 3 below. The molecular weights of β-cyclodextrin and citral are 1135 g / mol (dry) and 152 g / mol, respectively. The use of Actiphyte™ (Lubrizol Inc.) and other more concentrated plant essences may allow for even higher loading of deodorizing compounds on β-cyclodextrin.

[0065] [Table 3]

[0066] Additionally, commercial complexes such as citral / β-cyclodextrin complex (Wacker Chemical, CAVAMAX® W7 citral complex) can be used to impart good deodorizing performance to fluff pulp in solutions containing polar organic solvents. Commercially available complexes are believed to have a minimum citral content of 8.5% by weight, which suggests a minimum citral:β-cyclodextrin molar ratio of 0.7:1. The target value for the citral:β-cyclodextrin molar ratio is unknown, but is likely to be in the range of 1.0:1. The deodorizing solution may have a pH of 12.5, 12, 11, 10, or 9.6 or higher. Below a pH of about 12, deodorizing performance is significantly reduced. In certain embodiments, the pH is about 12.5. Further reducing the pH to 11 or further reducing to a pH of 10 improves commercial processability. In certain embodiments, the deodorizing solution has a pH greater than 9.6 and less than 12.5, a pH greater than 9 and less than 12.5, or a pH greater than 10 and less than 11. However, such commercially available complexes have extremely high costs, making them prohibitively expensive and impractical to implement on a commercial scale.

[0067] The deodorizing solution may also optionally contain a stabilizing additive. The stabilizing additive may help to prevent precipitation and crystallization of the dispersed complex of cyclodextrin and deodorizing compound. In particular, in certain embodiments, the molar ratio of the water-based solution is increased to reduce the solution concentration, and the sample is made at 50°C and pH 12.5. The stabilizing additive allows such a high molar ratio solution to be made at 20°C and pH 7, as in the embodiment shown in Example 14. The reduction in the mixing temperature and pH allows for excellent deodorizing performance with simplified commercial processing. Examples of acceptable stabilizing additives include, but are not limited to, stabilizing osmolytes, including corn syrup, glucose, high fructose corn syrup, trehalose, sucrose, sorbitol, amino acids, and their derivatives, and mixtures thereof. The deodorizing solution may include about 0.1% to about 14% by weight of the stabilizing additive, about 4% to about 14% by weight of the stabilizing additive, about 4% to about 10% by weight of the stabilizing additive, about 0.1% to about 1.0% by weight, or even 2.4% to 9.4% by weight of the stabilizing additive. In certain embodiments, the additive that provides a stabilizing effect on the dispersion is corn syrup, glucose, or high fructose corn syrup at a solution concentration of about 2% to 10% by weight, or even 6.2% to 9.4% by weight. In other embodiments, the additive that provides a stabilizing effect on the dispersion is trehalose at a solution concentration of about 0.1% to 1.0% by weight. In still further embodiments, the additive that provides a stabilizing effect on the dispersion is selected from the group consisting of protective or stabilizing osmolytes including sucrose, sorbitol, amino acids, and derivatives thereof.

[0068] The deodorizing solution described herein allows a cyclodextrin complex to be deposited from the deodorizing solution by precipitation, which allows for a rapid release of an odor-masking scent when hydrated with urine. A typical deodorizing compound is a scented essential oil that is released from the cyclodextrin complex upon hydration of the surface of the treated fiber or film. The deodorizing solution of the present disclosure can impart deodorizing properties to materials used in absorbent products. The deodorizing solution uses a fast-acting odor-masking deodorizer, e.g., a deodorizing compound, that can be incorporated into a cyclodextrin complex and deposited on fluff fibers. These fluff fibers, also known as cellulose fluff pulp, can be used as an absorbent filler for absorbent materials such as diapers, bed pads, and the like. The active ingredient (i.e., the deodorizing compound) can be stabilized in the cyclodextrin complex over a long storage period and released only when the fiber comes into contact with urine. Essential oil fragrances and organic deodorants can be used to create stable cyclodextrin complexes that are highly soluble in polar organic solvent systems and water solvent systems. These soluble complexes can be sprayed or otherwise applied uniformly onto a sheet of fluff fibers. After cooling to room temperature, the cyclodextrin complexes are precipitated in situ on the fiber surface, resulting in an unexpectedly efficient use of odor masking agents and providing excellent deodorant properties when the fibers are hydrated with urine. The deodorant solution of the present disclosure (1) has a sufficient concentration of cyclodextrin complexes to impart urine deodorant properties when applied to materials used in absorbent products, and (2) has a low enough water loading so that no additional drying step is required after its application.

[0069] The deodorizing solution of the present disclosure, which provides deodorizing properties to materials used in absorbent products, may include an optional polar organic solvent, water, cyclodextrin, and one or more deodorizing compounds. Cyclodextrin complexes that include cyclodextrin and deodorizing compounds have low water solubility and are difficult to apply and retain uniformly on the surface of solid fibers or films. A solution that is composed of a polar organic solvent and water provides the ability to form cyclodextrin complexes in solution at elevated pH and temperature. Such deodorizing solutions also provide the solubility and solution stability desired for applying a homogeneous solution of cyclodextrin complexes uniformly on solid surfaces.

[0070] Substrate with deodorizing solution applied The substrate of the present disclosure has applied thereon a deodorizing solution, which is described in detail above, the discussion of which is incorporated herein by reference.

[0071] The substrate comprises at least 0.2 kg of deodorizing compound per 1000 kg of substrate. In certain embodiments, the substrate comprises at least 0.3 kg of deodorizing compound per 1000 kg of substrate. In other embodiments, the substrate comprises at least 0.6 kg, 0.8 kg, 1 kg, 1.5 kg, or 2 kg of deodorizing compound per 1000 kg of substrate.

[0072] Also, as a result of applying the deodorizing solution onto the substrate, the substrate may show an increase in moisture content of less than 2% by weight.In certain embodiments, the increase in moisture content may be less than 2% by weight, such as 1.6% by weight, 1.3% by weight, 1% by weight, etc., as discussed in this disclosure.That is, even after applying a sufficient amount of the deodorizing solution to achieve at least 0.2 kg of deodorizing compound per 1000 kg of substrate, the substrate may still show an increase in moisture content of less than 2% by weight, as measured by comparing the weight of the substrate before and after applying the deodorizing solution.

[0073] The deodorizing solution discussed above provides a cyclodextrin complex comprising cyclodextrin and a deodorizing compound. By utilizing a polar organic solvent and water at an elevated pH and temperature, the cyclodextrin complex can be provided in a homogeneous solution and applied to a substrate. The cyclodextrin complex precipitates in situ on the substrate after cooling to room temperature, and the substrate does not show a substantial increase in moisture content. In certain embodiments, the cyclodextrin complex can also be dispersed in the deodorizing solution without using a polar organic solvent to apply to the substrate. In certain embodiments, the substrate can show an increase in moisture content of less than 0.8% by weight as a result of applying the deodorizing solution on the substrate. In certain embodiments, the substrate can show an increase in moisture content of less than 5%, 4%, 3%, 2%, 1.7%, 1.6%, 0.6%, 0.4%, 0.2%, 0.13%, or 0.1% by weight. In a particular embodiment, the deodorizing solution may comprise 67% by weight of glycerol as a polar organic solvent, 12% by weight of water, 21% by weight of cyclodextrin and a deodorizing compound, where the cyclodextrin is unsubstituted β-cyclodextrin and the deodorizing compound is citral, the citral and the unsubstituted β-cyclodextrin are present in a molar ratio of 1.5 mol of citral per 1 mol of unsubstituted β-cyclodextrin, the substrate is fluff pulp, the substrate comprises 0.4 kg of citral per 1000 kg of fluff pulp, and the substrate exhibits an increase in moisture content of less than 0.13% by weight as a result of application of the deodorizing solution onto the substrate.In a particular embodiment, the deodorizing solution can be made from 85% by weight water and 8% by weight cyclodextrin and deodorizing compound without using a polar organic solvent, where the cyclodextrin is unsubstituted β-cyclodextrin, and the deodorizing compound is an equimolar blend of d-limonene and octanol, the deodorizing compound and the unsubstituted β-cyclodextrin are present in a molar ratio of 4.0 moles of deodorizing compound total per mole of unsubstituted β-cyclodextrin, the substrate is fluff pulp, the substrate comprises 0.51 kg of deodorizing compound per 1000 kg of fluff pulp, and the substrate exhibits an increase in moisture content of less than 1.7% by weight as a result of applying the deodorizing solution onto the substrate. There is great practical and economic value in limiting the moisture content of the substrate to less than about 2% by weight. Adding a drying step to a typical fluff pulp manufacturing machine requires capital in the range of $30 million to $40 million. It is therefore desirable to reduce the moisture content as much as possible.

[0074] The substrate is not limited to any particular substrate material. For example, the substrate can be fluff pulp in the form of compressed sheet or airlaid fiber, spunbond or carded nonwoven of synthetic or cellulose fibers, woven fabric, solid material, or absorbent article. When the substrate is a solid material, the solid material is selected from the group consisting of polymer foam, leather, and plastic film. When the substrate is an absorbent article, the absorbent article is an adult incontinence pad, a feminine hygiene pad, a pull-up underwear, an adult brief, a baby diaper, or a bed pad.

[0075] Articles containing substrates to which deodorizing solutions have been applied The articles of the present disclosure include the substrates discussed above, the discussion of which is incorporated herein by reference. The articles can include, but are not limited to, those that would benefit from the improved odor control achieved by the present disclosure. For example, such articles can include absorbent articles such as adult incontinence pads, feminine hygiene pads, pull-up underwear, adult briefs, baby diapers, or bed pads. Other substrates can include, but are not limited to, fluff pulp in the form of compressed sheets or airlaid fibers, spunbond or carded nonwovens of synthetic or cellulosic fibers, woven fabrics, or solid materials such as polymer foams, leather, or plastic films.

[0076] Method for producing deodorizing substrate The deodorizing substrate can be prepared by preparing a substrate and applying a deodorizing solution onto the substrate to obtain a deodorizing substrate. The substrate and the deodorizing solution are described in detail above, and the discussion is incorporated herein by reference.

[0077] The method may further include forming a deodorizing solution comprising water, cyclodextrin, a deodorizing compound, a stabilizing additive, and optionally a polar organic solvent. The deodorizing solution produced in the method may form a dispersion comprising a complex of cyclodextrin and a deodorizing compound. The dispersion is temporarily stable, so that the deodorizing solution comprising the dispersion can be applied to a substrate before destabilization of the dispersion occurs. When different components are used in the deodorizing solution, the formation of the dispersion can occur at different temperatures and pH. For example, when the stabilizing additive is corn syrup, the deodorizing solution can be produced at room temperature (i.e., about 20° C.) and a pH greater than 9. When the deodorizing solution is produced without corn syrup, the deodorizing solution can be produced at a temperature greater than 50° C. and a pH greater than 10.9. In certain embodiments, the deodorizing solution is produced by mixing water and a stabilizing additive (e.g., corn syrup) and then adjusting the pH of the mixture. The mixture can then be heated to a desired temperature, such as above 50° C., or maintained at room temperature (i.e., about 20° C.). Cyclodextrin and a deodorizing compound can then be added to the mixture. The mixture can then be applied to a substrate.

[0078] As discussed above, mixing of certain embodiments of the deodorizing solution can be performed at a temperature of about 50° C. or higher to produce a dispersion of the cyclodextrin and the deodorizing compound. However, in certain embodiments, mixing can be performed at room temperature (i.e., about 20° C.). In addition, the deodorizing solution can have a reduced pH, for example, 11.5, 11.0, 10.5, 10, 9.5, or 9. For example, the pH can range from 9 to 12.5. The reduction in both temperature and pH of the deodorizing solution makes it easier to commercially process higher molar ratios of the deodorizing compound to cyclodextrin (e.g., molar ratios of citral to cyclodextrin of 4.0 or even higher), both individually and collectively. The dispersibility of the higher molar ratios of the deodorizing compound to cyclodextrin was unexpected, which allows for improved deodorizing performance. The addition of a stabilizing additive (e.g., corn syrup) also prevents the precipitation and crystallization of the dispersed cyclodextrin complexes, reducing the destabilization of the dispersion. It is believed that the stabilizing additive (e.g., smaller glucose molecules) interacts with the outer surface of the chemically similar β-cyclodextrin complexes, reducing the rate and amount of crystallization and / or precipitation of the complexes. Thus, the stabilizing additive also further improves the performance of the deodorizing solution while avoiding an undesirable increase in the moisture content of the fluff pulp (i.e., maintaining a moisture increase of less than 2% by weight).

[0079] In certain embodiments, the deodorizing solution can be applied onto the substrate at an elevated temperature and pH. The disclosure "elevated temperature" means that the temperature is higher than room temperature. For example, the deodorizing solution can be applied onto the substrate at an elevated temperature of 70°C to 90°C. In certain embodiments, the deodorizing solution can be applied onto the substrate at an elevated temperature of 75°C to 90°C, 80°C to 90°C, or 83°C to 86°C.

[0080] In an exemplary embodiment, the fluff pulp in sheet form was untreated southern pine kraft pulp sold under the trade name RAYFLOC™ JLDE obtained from Rayonier Advanced Materials. A warm solution containing citral was sprayed onto the sheet of fluff pulp with a solution add-on of about 0.055 g of deodorizing solution per 1 g of fluff. After applying the deodorizing solution, the sheet was not dried. The add-on of citral was calculated to be 2.0 kg of citral per 1 air-dried metric ton of fluff. The moisture content of the fluff pulp increased by 0.65%, i.e., from 8% moisture to 8.65% moisture. It may be beneficial to keep the moisture content increase to a level of less than 1%, let alone less than 5%.

[0081] The complexation of citral with β-cyclodextrin reduces the evaporation of citral when dry, but allows the release of the citral scent when the complex is hydrated with water. In an exemplary embodiment, there was no detectable scent when dry, but an immediate and noticeable release of lemon scent was observed when hydrated with only 2.5 g of water per gram of fluff. Furthermore, this exemplary embodiment effectively masked the odor of warm urine (35°C to 40°C) using 2.5 g of urine per gram of fluff to 10 g of urine per gram of fluff.

[0082] Other benefits that the solution gives to fluff pulp Glycerol used in the solution formulation can impart additional benefits to the fluff pulp such as reduced Mullen of the sheet and reduced compressibility of the fiberized fluff pulp.

[0083] For example, when one side of a sheet of RAYFLOC™ pulp was sprayed with a solution of 85% by weight glycerol and 15% by weight water at 80° C. at 0.08 g of solution per gram of pulp, the Mullen dropped from 1472 kPa to an average value of 1107 kPa. Burst strength (i.e., Mullen) is the hydrostatic pressure applied at a controlled rate required to cause rupture of a conditioned specimen. To obtain a burst strength (i.e., Mullen) measurement, pressure is applied at a controlled rate through a rubber diaphragm to a 30.48 mm (1.20 in) diameter circular area of ​​the specimen. The material being tested is initially flat and is held firmly at the periphery of the test position. As pressure is increased, the sample is free to expand and eventually burst. Burst strength (i.e., Mullen) is recorded as the pressure in kPa at rupture.

[0084] A similar treatment was found to improve the mechanical properties of fluff pulp airlaid sheets. Mechanical properties related to softness and hand are KES shear modulus and compression energy. The shear modulus of fluff pulp at 400 g / sm basis weight and 0.37 g / cc density decreased by 20% and compression energy by 29%. These values ​​indicate that the OCF airlaid core may feel softer than untreated fluff pulp. The Kawabata Evaluation System (KES) is used to make an objective measurement of hand properties. At low stress, the KES instrument measures mechanical properties that correspond to the basic deformation of the fabric when it is manipulated by hand. The samples were conditioned and the tests were carried out at laboratory atmospheric conditions of 21°C ± 2°C and 65% ± 5% RH. The samples had a width of 20 cm. Three replicate values ​​are obtained for shear stiffness. In shear testing, the specimens are subjected to opposing parallel stresses with a KES-FB1 tensile-shear tester until a maximum offset angle of 0.5° is reached. A pretension load of 50 gf / cm is applied. Lower values ​​of shear stiffness (gf / cm x degree) indicate less resistance to shear motion, which corresponds to a softer material. EXAMPLES

[0085] The features and advantages of solutions containing cyclodextrin that impart odor-eliminating properties to materials used in absorbent products and related products and methods are presented in more detail with respect to the following illustrative examples and embodiments.

[0086] Example 1: Preparation of Cyclodextrin Complexes in Solution In the following examples, β-cyclodextrin was obtained from Acros Organics (CAS: 7585-39-9) and Wacker Chemical under the trade name W7. Citral is a volatile lemongrass scented essential oil obtained from Perfumer's Apprentice (CAS: 5392-40-5).

[0087] A solution was first prepared by blending 85% by weight glycerol and 15% by weight water and raising the pH to 12.5 with sodium hydroxide. 50 g of this mixture was heated after pH adjustment. At about 75° C., 11.5 g of β-cyclodextrin was added. Heating and stirring was continued at around 86° C. until the β-cyclodextrin was completely dissolved. At that point, 2.3 g of citral was added (using a molar ratio of 1.5 mol of citral per mol of β-cyclodextrin) and stirring was continued for several minutes until a clear, colorless, transparent solution was obtained. This solution contained 21.6 g of β-cyclodextrin and citral per 100 g of solution, 66.7 g of glycerol per 100 g of solution, and 11.8 g of water per 100 g of solution. The water content of the β-cyclodextrin (maximum 10% by weight) was not taken into account in these calculations.

[0088] Example 2: Determination of pH In the following examples, the pH of untreated RAYFLOC™ fluff from Rayonier Performance Fibers, LLC was compared to an exemplary embodiment 31-5 OCF (deodorizing fiber) treated with a solution of the present disclosure. The solution applied to the 31-5 OCF sample contained 66.6% by weight glycerol, 11.8% by weight water, 18.0% by weight β-cyclodextrin, and 3.6% by weight citral (i.e., a molar ratio of citral:cyclodextrin of 1.5:1). The pH of the glycerol / water solution was adjusted to a pH of 12.5 at room temperature using sodium hydroxide. The 31-5 OCF sample was made at 86° C. using a solution load of 0.011 grams of solution per gram of fluff to obtain a citral load of 0.4 kg of citral per air-dried metric ton of fluff. Using the following test method, the 31-5 OCF sample had a pH of 5.8 and the untreated RAYFLOC™ fluff had a pH of 6.0, as shown below in Table 4. The use of higher pH solutions had little effect on the pH of the 31-5 OCF.

[0089] [Table 4]

[0090] The method for determining fiber pH is shown as follows. Fiber pH was determined by placing 2 grams of defibrillated sample into a 500 mL Erlenmeyer flask. 100 grams of distilled water with a pH of 6.5-7.0 was added. The flask was capped with a glass stopper and shaken until a thick slurry was obtained. Before stopping the flask, an additional 100 grams of distilled water was added to the flask and gently shaken at approximately 15 minute intervals until the sample was completely slurried. After approximately 1 hour, approximately 50 mL of the slurry was poured into a clean 150 mL beaker. This portion was used to rinse the beaker and discarded. The remaining slurry was then poured into the beaker and the pH was determined using a pre-calibrated pH meter.

[0091] Example 3: Citral Dose / Response on Urine Deodorization In the following examples, the dosage and response of citral on urine odor neutralization in exemplary embodiments was determined.

[0092] Exemplary embodiments were made by varying the citral add-on amount over a range of 0.1 kg to 3.3 kg citral per air-dried metric ton of fluff using the solution described in Example 2. The citral add-on amount was varied by adjusting the solution add-on amount. The fluff pulp in sheet form was untreated southern pine kraft pulp sold under the trade name RAYFLOC™ JLDE obtained from Rayonier Advanced Materials, Jessup, Georgia. Table 5 below summarizes the variations used to determine the citral amount and response on urine odor control.

[0093] [Table 5]

[0094] As shown in FIG. 1, odor reduction performance, measured as total odor score, increased with increasing citral addition up to a value of about 0.3 kg to 0.4 kg citral per air-dried metric ton of fluff and then remained constant up to a value of 3.3 kg citral per air-dried metric ton of fluff.

[0095] The resulting embodiments shown in Table 5 were evaluated according to the following methods.

[0096] Urinary odor evaluation of OCF using a blinded three-way forced-choice test by expert panelists Sample preparation - 400g / cm 2 ±approx.5g / cm 2Individual samples 60 mm in diameter were die cut from sheets of airlaid fluff pulp having a weight of 100 g and a density of about 0.06 g / cc. For each odor test, eight samples of the control material and six samples of the unknown or test material were made. The samples were placed in cylindrical carbonate or glass bottles 70 mm in diameter and 70 mm in height. The volume of the bottles was approximately 270 cm. 3 Each bottle had a plastic screw-on lid. Each bottle contained one sample and was dosed with either distilled water or fresh urine and heated in a water bath at 40°C ± 5°C between tests. Dosing was done with a calibrated syringe, taking care to distribute the liquid evenly throughout the sample. Between tests the bottles were washed with unscented dishwashing liquid.

[0097] Study Design - There were two parts to the odor study. In the first part, one test sample was spiked with urine and compared to two control samples spiked with distilled water. In the second part, another test sample spiked with urine was compared to two control samples also spiked with urine. Table 6 below shows the comparison.

[0098] [Table 6]

[0099] There are 12 odor comparisons for each test sample. There are two parts to the test, with three levels of urine input (i.e., 2.5g, 5g, and 10g liquid per 1g dry sample) in each part at both 10 and 100 minutes after input. The samples were maintained at a temperature of 40°C ± 5°C during the test. In the first part of the test above, for convenience, the same two control samples containing 10g water per 1g fluff were compared to three separate test samples made with urine at three dilution levels. Only these two control samples are used, as the odor of the water-containing control does not change after opening the bottle or over time. After the 10 minutes of odor testing, the samples were returned to the water bath for an additional 100 minutes before a final odor evaluation was made. In the second part of the test, the two urine-containing control samples were compared to one urine-containing test sample, with separate samples used for each comparison. In summary, six samples of test material containing urine were prepared (three dilution levels each for Parts 1 and 2), six control samples containing urine were prepared (three dilution levels each for Parts 1 and 2), and two additional control samples containing the distilled water used in Part 1 (10 g water per 1 g fluff) were prepared.

[0100] Panelists-Test Administrators performed each odor evaluation by removing the appropriate bottle from the water bath and presenting them to the panelists in a blinded manner. Panelists removed the lids of each bottle and recapped them after smelling the headspace of each bottle. Panelists were instructed to select one of the three bottles that was different from the other two, even if they had to guess. This statistical technique is called "three-way forced choice." Panelists would tell the Test Administrator which sample was different and whether their choice was a "detection" (i.e., they were certain their choice was different from the other two) or a "guess" (i.e., they were not certain their choice was different from the other two). If the panelist made a correct choice and their choice was a "detection," the Test Administrator would record a value of "6" for that comparison. If the panelist guessed their choice, a value of "2" was recorded for a correct guess and a value of "0" was recorded for an incorrect guess. Table 7 below shows the response legend.

[0101] [Table 7]

[0102] The odor values ​​of 2 and 6 are used because sensory responses such as odors follow a power law, where the apparent odor intensity is expressed as a power function of the input amount or odor concentration, i.e., I = kC n (1) and log 10 I=nlog 10 C+log 10 K (2) where I is odor intensity or odor strength, C is a measure of the mass concentration of the odorant, and k and n are constants that vary from odorant to odorant. Equation (2) is plotted linearly on a log-log scale. The dilution level in the test doubles at each step and is related to C, the mass concentration of the odorant. log 10 The conversion is used to provide an even interval (i.e., 0.301) between the levels of 2.5 g, 5 g, and 10 g of liquid per gram of fluff. In the test, this provides an even interval between the upper and lower limits of I, the odor score. Thus, the log 10 (2 x 0.301) is 4, the interval of odor score values ​​between 6 and 2.

[0103] The panelists also provide the test administrator with a rating of the pleasantness or unpleasantness of the odor of the test sample compared to the odor of the control sample. For example, if the panelist made a correct choice and was confident of their choice (i.e., it was a "perception") and the odor of the selected test sample was more pleasant than the odor of the control sample, the test administrator would record a value of "+6" for the comparison. If the test sample was more unpleasant than the control sample, the test administrator would record a value of "-6."

[0104] There is one more possible situation in the test. If the scented test sample containing urine can be reliably distinguished from the control sample containing water, but the test sample containing urine did not have a detectable urine odor, the result is recorded as "±6", indicating that both odors are subjectively acceptable. For example, together with an undetectable urine odor, a lemongrass scent may be as acceptable as a completely unscented sample. The choice depends on the panelist's preference. When the odor scores are summed up, "±6" is scored as "+6" since it is as good as the untreated control containing distilled water.

[0105] Panelists for the odor test can be recruited from the community. People who smoke, are pregnant, or have chronic allergies or asthma or nasal congestion are not candidates for the odor panel. Panelists should be free of colds and other respiratory illnesses at the time of testing and should not chew gum or eat within 30 minutes prior to testing. Panelists should not wear perfume, cologne, aftershave, or scented deodorant on the day of testing. Fresh urine collected from each panelist on the morning of the odor test is used to prepare samples for each panelist. Panelists need only smell their own urine. Urine is discarded at the end of each day.

[0106] Odor Score Analysis - The following examples illustrate the calculation and analysis of odor scores. The first example is a test of OCF 31-4 versus untreated RAYFLOC™ fluff pulp. That is, RAYFLOC™ fluff pulp was the control sample in this odor test.

[0107] [Table 8]

[0108] In the first part of the test, the odor score was ±6 at 2.5g and 5g urine per 1g 31-4 OCF sample (10 min). This indicates that there was no detectable urine odor in the 31-4 sample compared to untreated fluff with distilled water. At 10g urine per 1g OCF sample, the lemongrass scent was barely detectable, but there was still no detectable urine odor. At 10g urine per 1g 31-4 OCF sample and 100 min, there was a detectable urine odor in the 31-4 sample and an odor score of "-6" was recorded.

[0109] In the second part of the test, the odor of the 31-4 OCF sample with urine was detectable (and more pleasant) than untreated RAYFLOC™ with urine (i.e., a value of "+6"). At 100 minutes and the highest urine dose (i.e., 10 g of urine per gram of fiber), panelists were required to guess that the 31-4 OCF sample was different and had a more pleasant odor, and they guessed correctly.

[0110] The second example is a test of the 31-4 OCF sample versus itself, i.e., the 31-4 OCF sample was the control sample in this odor test.

[0111] [Table 9]

[0112] In the first part of the test, the odor score values ​​were negative. This may be due to the fact that it is easier to detect a slight urine odor in the scented 31-4 sample with urine versus the scented 31-4 sample with water than in the first example to detect a urine odor in the scented 31-4 sample with urine versus the unscented fluff sample with water. In the second part of the test, all values ​​were "0". All samples were the same and the panelists had to guess which sample to arbitrarily designate as the test sample. The panelists guessed incorrectly in all cases, but there was a 33% chance of randomly making the correct choice.

[0113] The odor score from the first part of the test is a comparison between an unknown material containing urine and a control material containing distilled water. The odor score from the second part of the test is a comparison between the same unknown material containing urine and the same control material containing urine. The total odor score is the sum of the odor scores from the first and second parts of the test. Tests using samples containing superabsorbent polymers and samples cut from absorbent cores and absorbent products can be used, as well as variations of the test using other reference materials for control. The odor score provides a good semi-quantitative measure of the effectiveness of the odor eliminating properties of the present invention.

[0114] Example 4: Deodorizing performance of citral / β-cyclodextrin complex The following examples feature the unexpected discovery that the odor eliminating performance of a β-cyclodextrin / citral complex can be improved by forming the complex in a solution at pH 12.5 and applying the solution at elevated temperature such that the complex precipitates in situ on the fiber surface at room temperature. The following examples also feature the unexpected discovery that the odor eliminating performance of the citral:β-cyclodextrin complex exhibited an optimum at a molar ratio of citral:β-cyclodextrin of about 1.5:1.

[0115] Table 10 below shows the performance of exemplary citral / β-cyclodextrin embodiments that reduce the citral add-on (kg citral per air-dried metric ton fluff) using citral:β-cyclodextrin molar ratios of 1.0:1, 1.5:1, and 1.75:1. Additionally, the control sample used to generate odor scores was made from untreated RAYFLOC™ fluff from Rayonier Performance Fibers, LLC. Odor scores were determined by the three-way forced choice test method discussed above. As seen in Table 10 below, odor reduction performance was best for a citral:β-cyclodextrin molar ratio of 1.5:1, and was independent of the citral add-on over the range of 3.3 kg to 0.4 kg citral per ADMT fluff pulp at that molar ratio. At a molar ratio of citral:β-cyclodextrin of 1.75:1, there was barely noticeable odor and color on the fluff pulp, indicating that not all of the citral was complexed with the cyclodextrin.

[0116] [Table 10]

[0117] The best odor eliminating performance was achieved by using a molar ratio of citral:β-cyclodextrin of 1.5:1 and a solution pH of 12.5. Table 11 below shows the performance of an exemplary embodiment of citral / β-cyclodextrin made with a molar ratio of citral:β-cyclodextrin of 1.5:1 as a function of solution pH, mixing temperature, and application temperature. The first group of three samples was made with a solution mixed and applied at an elevated temperature of 86°C. In the second group, the solution was mixed at an elevated temperature, but cooled and applied at room temperature. In the third group, the solution was mixed and applied at room temperature. In all groups, the odor score increased (i.e., performance improved) with increasing pH. No significant differences were found between groups as a result of normal variations in odor test scores.

[0118] [Table 11]

[0119] The control sample used to generate the odor scores in Table 11 was the 31-4 sample used in Example 3. The 31-4 sample was also tested as sample number 1 in Table 11 above. The water (i.e., control) vs. urine odor scores were all negative because it is easier to detect slight differences in urine malodor between similarly scented samples than it is to detect slight urine malodor in a scented sample compared to an unscented sample such as RAYFLOC™ fluff treated with water. The 31-4 sample was advantageous because the complex formed a clear, homogenous solution at an elevated temperature of about 86°C. At this stage, the odor eliminating performance of the complex was not improved. However, the ability to handle the solution and apply it uniformly to the substrate surface was greatly improved. A solution of the β-cyclodextrin / citral complex was sprayed onto fluff pulp at an elevated temperature of about 86°C, resulting in in situ precipitation onto the fiber surface upon cooling to room temperature.

[0120] Turbidity is an indication of the solubility of the complex in solution. Soluble complexes form clear, colorless, transparent solutions. Insoluble complexes form opaque milky dispersions that may settle over time. A milky dispersion forms if the 86°C solution is cooled to room temperature or no heat is used during the mixing or application steps. A laboratory simulated kiss roll method was used to apply the milky dispersion of the complex to fluff pulp. A known amount of the milky dispersion was applied to a glass surface and a fluff pulp sheet was immediately contacted to the glass surface and the dispersion was then allowed to dry. The wet pick-up of the dispersion was estimated by immediately weighing the sheet of fluff pulp.

[0121] Without being bound to a sole and complete understanding of the physicochemical changes imparted by the interaction of the citral / β-cyclodextrin complex with solution pH, the inventors believe that the unique physical morphology of the precipitate formed on the solid cellulose surface may provide an unexpected performance improvement in odor eliminating properties for samples made using an elevated solution pH of 12.5. Figures 2 and 3 are the following micrographs showing the particle size of citral / β-cyclodextrin complex precipitated from glycerol / water solutions at pH 12.5 and 9.6 at 86°C after the solutions were cooled to room temperature.

[0122] The solid particles of the complex precipitated from the pH 12.5 solution were uniform in size and had a diameter of about 50 μm. The particles precipitated from the pH 9.6 solution had sizes ranging from 100 μm to 400 μm. It was an unexpected discovery to find that the odor eliminating performance of the β-cyclodextrin / citral complex could be improved by complexing in a glycerol / water solution at a molar ratio of citral:β-cyclodextrin of about 1.5:1 and an elevated pH of about 12.5.

[0123] Example 5: Preparation of substrate The samples were made using β-cyclodextrin from Acros Organics and citral, a volatile lemongrass scented essential oil from Perfumer's Apprentice, with a glycerol / water ratio of 85 / 15 and a pH adjustment of 9.6. The solution was mixed and applied at a temperature of 86° C. At the application temperature of 86° C., the ingredients formed a clear, colorless, transparent solution. The molar ratio of citral to β-cyclodextrin was 1.0. The citral add-on was 2.4 kg of citral per air-dried metric ton ("ADMT") of fluff. The fluff pulp in sheet form was untreated southern pine kraft pulp sold under the trade name RAYFLOC™ JLDE, obtained from Rayonier Advanced Materials, Jessup, Georgia. The calculated increase in moisture content of the substrate was 1.0% by weight. This was confirmed using a METTLER TOLEDO™ moisture analyzer. Here, the treated sample had a moisture content of 6.29%±0.18% and the untreated Rayfloc control had a moisture content of 5.33%±0.39%. The experimental moisture gain of the sample was 0.96%. Since the moisture gain was less than about 1% by weight, no drying step was required. The overall odor score was −28 as determined by the blinded three-way forced choice test by the expert panel discussed above. This sample did not exhibit good odor control performance, even with the relatively high amount of citral added. The citral addition was 2.4 kg of citral per air-dried metric ton ("ADMT") of fluff. The poor odor control performance was due to the molar ratio of citral:β-cyclodextrin being less than 1.5:1 and the solution pH being less than pH 12. The specifications and odor score measurements for Example 5 are shown in Tables 12 and 13.

[0124] [Table 12]

[0125] [Table 13]

[0126] Example 6: Preparation of substrate The samples were made using β-cyclodextrin from Acros Organics and citral from Perfumer's Apprentice, with a glycerol / water ratio of 85 / 15 and a pH adjustment of 12.5. The solutions were mixed and applied at a temperature of 86° C. At the application temperature of 86° C., the ingredients formed a clear, colorless, transparent solution. The molar ratio of citral to β-cyclodextrin was 1.0. The citral add-on was 2.4 kg of citral per air-dried metric ton ("ADMT") of fluff. The fluff pulp in sheet form was untreated southern pine kraft pulp sold under the trade name RAYFLOC™ JLDE, obtained from Rayonier Advanced Materials, Jessup, Georgia. The calculated increase in moisture content of the substrate was 1.0% by weight. Because the moisture increase was less than about 1% by weight, no drying step was required. The overall odor score was +16 as determined by the blinded three-way forced choice test by the expert panel discussed above. This sample exhibited better odor eliminating properties than the sample in Example 5 because the solution pH was increased from 9.6 to 12.5. The specifications and odor score measurements for Example 6 are shown in Tables 14 and 15.

[0127] [Table 14]

[0128] [Table 15]

[0129] Example 7: Preparation of substrate The samples were made using β-cyclodextrin from Acros Organics and citral from Perfumer's Apprentice, with a glycerol / water ratio of 85 / 15 and a pH adjustment of 12.5. The solutions were mixed and applied at a temperature of 86° C. At the application temperature of 86° C., the ingredients formed a clear, colorless, transparent solution. The molar ratio of citral to β-cyclodextrin was 1.5. The citral add-on was 2.0 kg of citral per air-dried metric ton ("ADMT") of fluff. The fluff pulp in sheet form was untreated southern pine kraft pulp sold under the trade name RAYFLOC™ JLDE, obtained from Rayonier Advanced Materials, Jessup, Georgia. The calculated increase in moisture content of the substrate was 0.6% by weight. Because the moisture increase was less than about 1% by weight, no drying step was required. The overall odor score was +56 as determined by the blinded three-way forced choice test method by the expert panel discussed above. As a result of the 1.5:1 molar ratio of citral to β-cyclodextrin and the solution pH of 12.5, this sample showed very good odor eliminating performance. The specifications and odor score measurements of Example 7 are shown in Tables 16 and 17.

[0130] [Table 16]

[0131] [Table 17]

[0132] Example 8: Preparation of substrate The samples were made using β-cyclodextrin from Acros Organics and citral from Perfumer's Apprentice, with a glycerol / water ratio of 85 / 15 and a pH adjustment of 12.5. The solutions were mixed and applied at a temperature of 86° C. At the application temperature of 86° C., the ingredients formed a clear, colorless, transparent solution. The molar ratio of citral to β-cyclodextrin was 1.5. The citral add-on was 0.4 kg of citral per air-dried metric ton ("ADMT") of fluff. The fluff pulp in sheet form was untreated southern pine kraft pulp sold under the trade name RAYFLOC™ JLDE, obtained from Rayonier Advanced Materials, Jessup, Georgia. The calculated increase in moisture content of the substrate was 0.1% by weight. Because the moisture increase was less than about 1% by weight, no drying step was required. The overall odor score was +52, as determined by the blinded three-way forced choice test method by the expert panel discussed above. With only 0.4 kg of added citral per 1 ADMT of fluff pulp, this sample showed odor eliminating performance as good as that of the sample made with 2.0 kg of added citral per 1 ADMT of fluff pulp (i.e., Example 7). The specifications and odor score measurements of Example 8 are shown in Tables 18 and 19.

[0133] [Table 18]

[0134] [Table 19]

[0135] Example 9: Preparation of substrate The samples were made using 100% water (i.e., glycerol / water in a 0 / 100 ratio) and a pH adjustment of 12.5, with β-cyclodextrin from Acros Organics and citral from Perfumer's Apprentice. The solutions were mixed and applied at a temperature of 86° C. At the application temperature of 86° C., the ingredients formed a relatively stable, milky dispersion. The molar ratio of citral to β-cyclodextrin was 1.5. The citral add-on was 0.4 kg of citral per air-dried metric ton ("ADMT") of fluff. The fluff pulp in sheet form was untreated southern pine kraft pulp sold under the trade name RAYFLOC™ JLDE, obtained from Rayonier Advanced Materials, Jessup, Georgia. The calculated increase in moisture content of the substrate was 1.1% by weight. Since the moisture increase was approximately 1% by weight, no drying step was required. The overall odor score was +36, as determined by the blinded three-way forced choice test method by the expert panel discussed above. The odor eliminating performance of this cost-saving 100% aqueous solution sample was good, and was as good as the sample made in Example 8 using 85 / 15 glycerol / water solution. This mixture formed a dispersion after the addition of citral and the formation of a complex at 86°C, but when the concentration of cyclodextrin and citral in the solution was less than about 20% by weight, the size of the precipitated particles was very small, the odor eliminating performance was good, and the dispersion could be easily sprayed onto a substrate. The specifications and odor score measurements of Example 10 are shown in Tables 20 and 21.

[0136] [Table 20]

[0137] [Table 21]

[0138] Conclusion and Summary of Examples 5 to 9 A summary of Examples 5 to 9 is shown in Table 22 below. With a glycerol / water ratio of 85 / 15 and citral loading ranging from 2.0 kg to 2.4 kg of citral per 1 ADMT of fluff pulp, when the molar ratio of citral:cyclodextrin was increased from 1:1 to 1.5:1, the odor eliminating performance increased by approximately the same amount (as indicated by the increase in the total odor score) as with an increase in solution pH from 9.6 to 12.5. The pH of the unadjusted solution was about 6.5. Using a smaller loading of the same solution, a reduced citral loading of 0.4 kg of citral per 1 ADMT of fluff pulp also gave approximately the same level of very good performance (i.e., +52) at a molar ratio of citral:cyclodextrin of 1.5:1 and a pH of 12.5. Examples 5 to 8 gave clear, colorless, transparent solutions at a mixing temperature and application temperature of 86°C. The composite was deposited onto the surface of the cellulose fibers from a solution and the treated fibers were cooled to room temperature.

[0139] [Table 22]

[0140] It was an unexpected discovery to find that the odor eliminating performance of a β-cyclodextrin / citral complex could be significantly improved by complexing in a glycerol / water solution at a molar ratio of citral:β-cyclodextrin of about 1.5:1 and an elevated pH of about 12.5.

[0141] The exact physical dimensions and morphology of the cyclodextrin complexes precipitated in situ on the solid fiber surface have not been characterized. However, without being bound by any one theory, the inventors believe that the particle size of the complexes precipitated in solution as the solution cools to room temperature is a measure of the morphology of the complexes on the substrate surface. The average size of the solid particles of the complexes precipitated from a solution of pH 12.5 at elevated temperatures ranges from 50 μm or less. For good deodorant performance, a solution pH of about 12.5 or greater should be used. If a solution pH of 9.6 or less is used to treat the substrate, the deodorant performance is more poor. The average size of the solid particles of the complexes precipitated from a solution of pH 9.6 or less at elevated temperatures ranges from 100 μm to 400 μm. It is believed that the particle size is controlled, among other things, by the pH of the solution.

[0142] The results discussed above were surprising and unexpected. There is no known discussion in the prior art of the effect of pH on the deodorant performance of cyclodextrin complexes. This effect may be consistent with our additional finding that the complexes precipitate into very fine particles when precipitated from a solution having a pH of around 12.5. The deodorant performance of the complexes deposited from solution may be related to their solid-phase morphology on the substrate surface. The hydroxyl groups on the outer surface of the cyclodextrin molecule begin to deprotonate at about pH 12 (i.e., a pKa range of about 12.1 to 13.5). Cyclodextrin and its complexes are known to self-assemble in solution to form aggregate structures. The formation of these aggregates may be influenced by the surface charge associated with deprotonation, which in turn may affect the size of the precipitated particles and the morphology of the complexes deposited on the substrate surface. Other patents, such as US Pat. No. 5,399,343, claim that small cyclodextrin particles improve the release and release rate of active substances. Particles less than about 12 microns were preferred to provide a rapid release of the active compound when the complex was wetted. However, in US Pat. No. 5,999,136, this particle size reduction was achieved through grinding and pulverization in a fluid energy mill, or through stirring or ultrasonic treatment. The inventors are not aware of the use of solution pH to adjust the particle size of the cyclodextrin complex as disclosed herein.

[0143] The inventors have also unexpectedly found that deodorant performance may be sensitive to the molar ratio of citral to cyclodextrin in the complex. In WO 98 / 26808 and WO 98 / 26808, it is shown that perfume / cyclodextrin complexes generally have a perfume to cyclodextrin molar ratio of about 1:1, but may be greater, however typically the perfume loading on cyclodextrin is about 7% to 12% by weight. There is a practical limit to the perfume loading in cyclodextrin complexes, but the inventors are not aware of any disclosure of how the loading affects deodorant performance. In the case of citral / β-cyclodextrin complexes, a 1:1 molar ratio of citral to β-cyclodextrin corresponds to a loading of 11.8% by weight, as generally disclosed by WO 98 / 26808. However, a molar ratio of 1.5:1 citral to β-cyclodextrin would correspond to a loading of 16.7% by weight. Considering the moisture content of β-cyclodextrin of 10% by weight, a molar ratio of 1.5:1 citral to dry β-cyclodextrin would correspond to a loading of 18.3% by weight. That is, such a citral loading range is well beyond the range taught in U.S. Pat. No. 5,999,393. The inventors are not aware of any technical explanation that the higher range of citral loading disclosed may be driven by the high solution pH at which the complex is formed. Although the actual quantitative values ​​may vary with different essential oil loadings, the inventors expect that the requirements for achieving good deodorization, as a common feature of these systems, include a minimum loading value of essential oil to cyclodextrin and a solution pH above about 12.0.

[0144] The complexes in Examples 5 to 9 form clear homogeneous solutions at an elevated temperature of about 86°C. At this stage, the deodorizing performance of the complexes was not improved. However, the ability to handle the solution and apply it uniformly to the substrate surface was greatly improved. When a solution of β-cyclodextrin / citral complex is sprayed onto fluff pulp at an elevated temperature of about 86°C, it precipitates in situ on the fiber surface when cooled to room temperature. The solution concentration of citral / cyclodextrin complex ranged from 21.6% to 24.9% by weight. The solution concentration of the complex can reduce the amount of solution added to keep the moisture gain of the substrate below about 1% by weight. However, the ratio of deodorizing compound to cyclodextrin also helps to impart good deodorizing performance to the substrate. For citral, the optimal molar ratio of citral to β-cyclodextrin is about 1.5 mol to about 1.75 mol of citral to 1.0 mol of β-cyclodextrin. Below about a 1:1 molar ratio, odor eliminating performance decreases (for equal amounts of citral added to the substrate). Above a 1.75:1 molar ratio, the volatile uncomplexed citral imparts unwanted color and odor to the substrate. The volatile and expensive scented essential oils used in absorbent products tend to be lost early. It is desirable for the essential oil to be contained in a stable complex and released only upon contact with aqueous body fluids.

[0145] In the solution chemistry discussed above, the glycerol / water ratio also plays a role: for example, samples made with higher water ratios (e.g., 50% glycerol / 50% water) do not perform as well as samples made with 85% glycerol / 15% water ratios, even when made with the preferred 1.5 mol citral:1 mol cyclodextrin and pH 12.5.

[0146] However, it is worth noting that Example 9 shows almost the same deodorizing performance using a 100% aqueous solution, and can provide 0.4 kg of citral per 1 ADMT fluff pulp with only a 1.1% moisture increase. This unexpected practical discovery allows good deodorizing performance to be obtained with a significant reduction in raw material costs. In this embodiment, for good deodorizing performance from a 100% aqueous solution, the conditions must be suitable for the formation of fine precipitates upon addition of citral to the β-cyclodextrin / water solution. The solution concentration of the complex at 86°C and pH 12.5 is lower, in the range of about 18% by weight or less. At higher concentrations, undesirably coarse precipitates are formed, resulting in poor deodorizing performance.

[0147] Examples 10 to 17 Three-way forced-choice odor evaluation test protocol used in Examples 10 to 17 Odor scores were derived from comparison of the test sample to the reference sample, i.e., the control sample. The odor scores are not absolute. Both the test and control samples were spiked with fresh human urine aged at room temperature for 8-12 hours to enhance the malodor. The odor scores in Examples 10-17 below were direct comparisons of the test sample versus the reference sample at two levels of urine spike (i.e., 5g and 10g urine per gram of fluff) and two times after spike (i.e., 10 minutes and 100 minutes). The scoring range for this comparison was -24 to +24. In this three-way forced choice odor evaluation test, panelists choose one of three samples that has a different scent than the other two. Panelists must make a choice and there is no possibility of "no difference." A guess is when the panelist is unsure of their choice. A perception is when the panelist is certain of their choice. The rating scale is shown in Table 23 below.

[0148] [Table 23]

[0149] The samples in Examples 10-17 were tested against conventional fluff twice at lower urine input levels (i.e., 5.0 g urine per 1 g fluff at 10 minutes and 100 minutes). The scoring range for this comparison was -12 to +12. Except for the conventional fluff sample in Example 17, all test and control samples in Examples 10-17 achieved a perfect score of +12 against conventional fluff. This indicated that all control and test samples in Examples 10-17 blocked urine better than conventional fluff.

[0150] Example 10: Comparison of Citral / Coconut Fragrance Blends with Citral Alone A sample similar to that described in Example 9 was made using 100% water (i.e., glycerol / water in a ratio of 0 / 100) and a pH adjustment of 12.5, using β-cyclodextrin from Wacker Chemical Co. and citral from Advanced Biotech. A solution was prepared with a molar ratio of citral to β-cyclodextrin of 1.6 instead of 1.5 (not a meaningful difference), mixed and applied at a temperature of 86°C. The citral add-on was 0.4 kg citral per air-dried metric ton ("ADMT") of fluff. The fluff pulp in sheet form was untreated southern pine kraft pulp sold under the trade name RAYFLOC™ JLDE obtained from Rayonier Advanced Materials, Jessup, Georgia. The calculated increase in moisture content of the substrate was 1.0% by weight. Since the moisture increase was about 1% by weight, no drying step was required. This sample identified as 4-1 was used as a control sample in a three-way forced-choice odor evaluation against a test sample identified as 12-1, which was made using an equimolar blend of citral and coconut fragrance oil at the same total essential oil to β-cyclodextrin molar ratio of 1.6 and the same mixing and application temperature of 86° C. The total essential oil add-on for the equimolar blend of citral and coconut fragrance oil was increased to 0.46 kg per air-dried metric ton ("ADMT") of fluff to keep the samples at comparable raw material costs. The coconut fragrance oil supplied by Perfumer's Apprentice was a blend of several essential oils as shown in Table 24 below.

[0151] [Table 24]

[0152] The weighted average molecular weight of the coconut fragrance oil was about 180.2 g / mol. Sample 12-1 was also made using β-cyclodextrin from Wacker Chemical Co. and citral from Advanced Biotech.

[0153] The odor score of the test sample 12-1 containing the citral / coconut fragrance blend versus the control sample 4-1 was +24 out of a possible range of -24 to +24 as determined in the blinded three-way forced choice test discussed above. This revealed that an equimolar blend of citral and coconut fragrance oil improved odor eliminating performance over samples made with citral alone at somewhat higher add-on levels but comparable raw material costs. Specifications for the control sample 4-1 and the test sample 12-1 are shown in Table 25 (Control sample 4-1) and Table 26 (Test sample 12-1). The measured odor scores of the blended test sample 12-1 versus the control sample 4-1 are shown in Table 27 (Odor scores for test sample 12-1 versus control sample 4-1).

[0154] [Table 25]

[0155] [Table 26]

[0156] [Table 27]

[0157] Example 11: Reduction in solution mixing temperature from 86° C. to 50° C. achieved by increasing the EO to CD molar ratio from 1.6 to 4.0 Sample 4-1, described above in Example 10, was used as a control sample against a new test sample, identified as 52-1, made at a lower mixing temperature and higher molar ratio in a three-way forced-choice odor evaluation. The decrease in mixing temperature reduced the solubility and dispersibility of the citral / β-cyclodextrin complex. This decrease in dispersibility led to settling of the precipitated complex at a mixing temperature of 50°C. Such dispersions were difficult to apply to substrates and had poor odor-eliminating performance. Removal of β-cyclodextrin from the solution, resulting in an increase in the citral to β-cyclodextrin molar ratio to a value of 4.0, allowed for effective dispersion of solids at 50°C. At 50°C, the dispersion used to make test sample 52-1 was milky white and showed no noticeable precipitation or settling of particles.

[0158] Test sample 52-1 was made using β-cyclodextrin from Wacker Chemical Co. and citral from Advanced Biotech, using 100% water and a pH adjustment of 12.5. A solution was prepared with a molar ratio of citral to β-cyclodextrin of 4.0 and mixed and applied at a temperature of 50° C. (shown in the table as 50° C. / 50° C.). The citral add-on was increased to 0.5 kg of citral per air-dried metric ton ("ADMT") of fluff. The fluff pulp in sheet form was untreated southern pine kraft pulp sold under the trade name RAYFLOC™ JLDE, obtained from Rayonier Advanced Materials, Jessup, Georgia. The calculated increase in moisture content of the substrate was 1.3% by weight. Because the moisture increase was not much higher than 1% by weight, no drying step was required.

[0159] The odor score of test sample 52-1 vs. control sample 4-1 was +20 out of a possible range of -24 to +24 as determined by the blinded three-way forced choice test discussed above. Increasing the molar ratio of citral to β-cyclodextrin from 1.6 to a value of 4.0 improved odor eliminating performance. It was unexpected to see relatively good dispersibility of the solution at a mixing temperature of only 50°C. It was also unexpected that dried sample 52-1 had no citral odor even at a high citral to cyclodextrin molar ratio of 4.0. This indicates that most of the volatile citral oil is bound to the substrate under dry storage conditions. Specifications of control sample 4-1 and test sample 52-1 are shown in Tables 25 and 28 (test sample 52-1). The measured odor scores of test sample 52-1 vs. control sample 4-1 are shown in Table 29.

[0160] [Table 28]

[0161] [Table 29]

[0162] Example 12: Solution pH reduction from 12.5 to 10.9 achieved at 50° C. for d-limonene with added corn syrup Decreasing the pH reduced the solubility and dispersibility of the citral / β-cyclodextrin complex, which mimics the effect of decreasing the temperature on solubility and dispersibility. The dispersibility of the complex at pH 10.9 could be improved by adding water to reduce the solids concentration of the solution. This allowed the solution pH to be lowered at a temperature of 50° C. and some deodorizing performance to be maintained, but this approach resulted in an undesirable increase in the moisture content of the fluff pulp, sometimes exceeding 2%. An example of this approach is shown in Table 40 as Sample 46-B. In an attempt to find an additive that could prevent crystallization and / or precipitation of the dispersed complex at reduced temperatures and pH, it was found that the addition of a small amount of corn syrup (i.e., glucose) was effective in maintaining a sufficiently stable milky dispersion at pH 10.9 and 50° C. without noticeable precipitation or particle settling. It is believed that the smaller glucose molecules interact with the outer surface of the chemically similar β-cyclodextrin complex, reducing the rate and amount of crystallization and / or precipitation of the complex. The beneficial effect of adding glucose to a solution was demonstrated in the following example using a complex of d-limonene and β-cyclodextrin.

[0163] Test sample 65-1 was made using 82.7% water and 9.2% Karo's Light Corn Syrup at 50°C and pH 10.9, with β-cyclodextrin from Wacker Chemical Co. and d-limonene from Florida Chemical Company in place of citral. For the calculations in Table 28, the moisture content of the corn syrup was assumed to be 25% by weight. A solution was prepared with a d-limonene to β-cyclodextrin molar ratio of 4.0, mixed and applied at a temperature of 50°C. The pH was adjusted after the corn syrup was added to the water. Any fine precipitate that formed remained suspended for several hours. This was a very easy solution / suspension to handle and spray during the processing of the pulp sheet. The d-limonene addition was 0.5 kg d-limonene per air-dried metric ton ("ADMT") of fluff. The fluff pulp in sheet form was untreated southern pine kraft pulp sold under the trade name RAYFLOC™ JLDE obtained from Rayonier Advanced Materials, Jessup, Ga. The calculated moisture content increase of the fluff pulp base was 1.6% by weight. No drying step was required.

[0164] Test sample 65-1 was tested for odor compared to control sample 52-1. Sample 52-1 was used as the test sample in Example 11. In a paired comparison, sample 52-1 performed better than sample 4-1 in Example 11, and sample 65-1 performed better than sample 52-1 in Example 12. The odor score for test sample 65-1 vs. control sample 52-1 was +24 out of a possible range of -24 to +24, as determined by the blinded three-way forced choice test method discussed above. The addition of 9.2% by weight corn syrup to the solution along with the use of d-limonene greatly improved the dispersibility of the complex in the solution, resulting in very good masking of the urinary malodor. The dried sample of 65-1 had no scent. The specifications for control sample 52-1 and test sample 65-1 are shown in Table 28 (above) and Table 30 (test sample 65-1). The measured odor scores for test sample 65-1 versus control sample 52-1 are shown in Table 31 (Odor Scores for Test Sample 65-1 versus Control Sample 52-1).

[0165] [Table 30] TIFF2025514090000032.tif250170

[0166] [Table 31]

[0167] Example 13: Reduction in solution pH from 12.5 to 10.9 achieved at 50° C. for equimolar d-limonene / octanol blends with added corn syrup Similar samples as described in Example 12 were made using an equimolar blend of d-limonene and octanol instead of 100% d-limonene. For the calculations in Table 30, the moisture content of the corn syrup was assumed to be 25% by weight. Test sample 67-1 was tested for odor compared to control sample 52-1. Sample 52-1 was used as the test sample in Example 11 and the control sample in Example 12. The odor score for test sample 67-1 versus control sample 52-1 was +24 out of a possible range of -24 to +24 as determined by the blinded three-way forced choice test method discussed above. The addition of 9.2% by weight corn syrup to the solution and the use of an equimolar blend of d-limonene and octanol greatly improved the dispersibility of the complex in the solution and provided very good masking of the urinary malodor. The dried sample of 67-1 had no odor. Specifications for control sample 52-1 and test sample 67-1 are shown in Table 28 and Table 32 (Test Sample 67-1). The measured odor scores for test sample 67-1 versus control sample 52-1 are shown in Table 33 (Odor Scores for Test Sample 67-1 versus Control Sample 52-1).

[0168] [Table 32] TIFF2025514090000035.tif73170

[0169] [Table 33]

[0170] Example 14: Further increase in EO / CD molar ratio and decrease in pH and mixing temperature Samples similar to sample 67-1 described in Example 13 (Table 32) were made to extend the range of key variables: pH, mixing temperature, and EO / CD molar ratio. These samples were made using equimolar blends of d-limonene and octanol. The solutions used to make these samples contained 9.2% to 9.4% corn syrup, where the moisture content of the corn syrup was estimated to be 25% by weight. The solution pH and mixing temperature of sample 67-1 were pH 10.9 and 50°C, respectively. The pH of the solution used to make sample 68-1 was pH 7.0, and the mixing temperature of the solution used to make sample 69-1 was 20°C. Both of these samples had solution concentrations of CD and EO of 8.1%, similar to the solution concentrations of sample 67-1. The solution used to make sample 74-1 was made with an increased EO / CD molar ratio of 6.0 compared to 4.0 for 67-1, and the pH and mixing temperature for 74-1 were 10.9 and 50° C., respectively. Sample 74-1 had a solution concentration of CD and EO of only 6.4% due to the reduced amount of cyclodextrin. The specifications for sample 74-1 are shown in Table 34.

[0171] [Table 34] TIFF2025514090000038.tif252170

[0172] Test Sample 68-1, Test Sample 69-1, and Test Sample 74-1 were tested for urinary malodor in comparison to Control Sample 67-1. The odor scores of Test Sample 68-1, Test Sample 69-1, and Test Sample 74-1 versus Control Sample 67-1 as determined by a blinded three-way forced choice test are summarized in Table 35.

[0173] [Table 35]

[0174] The odor scores for test sample 68-1, test sample 69-1, and test sample 74-1 showed that although none of these samples were as good as control sample 67-1, their deodorizing performance was still relatively good. The deodorizing performance of sample 69-1 made at a solution mixing temperature of 20°C was almost as good as that of control sample 67-1. The decrease in pH and the increase in molar ratio had a greater negative effect on deodorizing performance than the decrease and increase in temperature. These samples were used to establish the range of key factors for the optimal deodorizing performance of samples containing corn syrup.

[0175] Example 15: Further reduction in solution concentration of corn syrup Samples similar to Sample 67-1 described in Example 13 (Table 32) were made to extend the range of the key variable, the solution concentration of corn syrup. These samples were made using equimolar blends of d-limonene and octanol. The solutions used to make these samples contained 9.2% to 3.3% corn syrup, where the moisture content of the corn syrup was estimated to be 25% by weight. The pH of the solutions used to make the samples was pH 10.9, the mixing temperature was 50°C, and the EO / CD molar ratio was 4.0. The solution concentrations of CD and EO ranged from 8.1% to 13.8%. The specifications of Sample 72-1, Sample 70-1, and Sample 82-1 are shown in Tables 36, 37, and 38.

[0176] [Table 36] TIFF2025514090000041.tif253170

[0177] [Table 37] TIFF2025514090000043.tif252170

[0178] [Table 38] TIFF2025514090000045.tif254170

[0179] Test sample 72-1, test sample 70-1, and test sample 82-1 were tested for urine malodor in comparison to control sample 67-1. The odor scores of the test samples versus control sample 67-1, as determined by a blinded three-way forced choice test, are summarized in Table 39.

[0180] [Table 39]

[0181] The deodorizing performance of Samples 67-1, 72-1, and 70-1 decreased with increasing solution concentration of CD and EO and decreasing solution concentration of corn syrup. Sample 82-1 showed that when the total solution concentration of CD and EO was low at about 8% to 9%, low concentration corn syrup in the range of 3.3% was effective.

[0182] Example 16: Summary of samples in Examples 10 to 17 The relative deodorizing performance of the samples in Examples 10 to 17 was also summarized using an odor performance score that represents a continuous performance scale based on multiple pairwise comparisons. For example, if sample 4-1 was +24 compared to conventional fluff, and sample 52-1 was +20 compared to sample 4-1, and sample 67-1 was +24 compared to sample 52-1, then sample 67-1 was +68 compared to conventional fluff. The scale is not linear, and a given quantitative difference at the lower end of the scale is more meaningful than the same difference at the upper end. The continuous deodorizing scores of these samples are shown in Table 40. The range of the key factors for optimal deodorizing performance is also shown in this table. The key factors are the total essential oil (EO) added to the substrate, the mixing temperature of the solution, the molar ratio of essential oil to cyclodextrin in the solution, the pH of the solution, and the concentration of corn syrup in the solution.

[0183] [Table 40] TIFF2025514090000048.tif251170

[0184] Example 17: Comparison of deodorizing fluff samples with conventional fluff The test and control samples in Examples 10-16 all achieved a perfect score of +12 against the conventional fluff in the odor eliminating test, indicating that the samples in Examples 10-16 masked the malodor of urine much better than the conventional fluff. Table 41 below shows examples of odor scores for two test samples versus the conventional fluff control sample.

[0185] [Table 41]

[0186] In the above description, the solution containing cyclodextrins that imparts odor-eliminating properties to materials used in absorbent products, and the related products and methods of the present application have been described with reference to specific embodiments thereof. However, it will be apparent that various modifications and changes can be made without departing from the broader spirit and scope of the present invention. The specification and drawings are therefore to be regarded in an illustrative rather than a restrictive sense. Throughout this specification, unless the context otherwise requires, the word "comprise" and its variations such as "comprises" and "comprising" are understood to mean the inclusion of the specified item, element, or step, or group of items, elements, or steps, but not the exclusion of any other items, elements, or steps, or group of items, elements, or steps. Furthermore, the indefinite article ("a" or "an") is to be interpreted as indicating one or more of the item, element, or step modified by the article.

Claims

1. A substrate having an applied deodorizing solution, The deodorizing solution is Water, Cyclodextrin, A deodorizing compound; Optionally, a polar organic solvent; where The substrate comprises at least 0.2 kg of the odor eliminating compound per 1000 kg of the substrate; and A substrate, wherein upon application of said odor eliminating solution onto said substrate, said substrate exhibits an increase in moisture content of less than 2% by weight.

2. The substrate of claim 1 , wherein the odor eliminating solution further comprises a stabilizing additive.

3. 2. The substrate of claim 1, wherein the deodorizing solution comprises 1.5 mol to 6 mol of the deodorizing compound per mol of the cyclodextrin.

4. 10. The substrate of claim 1, wherein the deodorizing solution has a pH greater than 9 and less than 12.

5.

5. 10. The substrate of claim 1, wherein said deodorizing solution comprises from about 6% to about 19% by weight of said cyclodextrin and said deodorizing compound.

6. 10. The substrate of claim 1, wherein the odor eliminating compound is selected from the group consisting of citral, coconut fragrance oil, d-limonene, octanol, and combinations thereof.

7. 10. The substrate of claim 1, wherein the substrate exhibits an increase in moisture content of less than 1.7% by weight as a result of application of the odor eliminating solution onto the substrate.

8. The deodorizing solution contains 3.5 mol to 4.5 mol of the deodorizing compound per 1 mol of the cyclodextrin, and The substrate according to claim 3, wherein the deodorizing solution is mixed at a temperature of 20°C or higher before application to the substrate to form a dispersion containing a complex of the cyclodextrin and the deodorizing compound.

9. The substrate of claim 2, wherein the odor eliminating solution comprises from about 0.1% to about 14% by weight of the stabilizing additive.

10. 3. The substrate of claim 2, wherein the stabilizing additive is selected from the group consisting of corn syrup, glucose, high fructose corn syrup, trehalose, sucrose, sorbitol, amino acids, derivatives thereof, and combinations thereof.

11. the stabilizing additive is selected from the group consisting of corn syrup, glucose, high fructose corn syrup, derivatives thereof, and combinations thereof; The substrate of claim 2, wherein the odor eliminating solution comprises from about 2% to about 10% by weight of the stabilizing additive.

12. The stabilizing additive is trehalose, and The substrate of claim 2, wherein the odor eliminating solution comprises from about 0.1% to about 1.0% by weight of the stabilizing additive.

13. The deodorizing solution further comprises glucose and / or corn syrup as a stabilizing additive; said deodorizing solution comprising from about 2.4% to about 9.4% by weight of said stabilizing additive; said deodorizing solution comprising from about 3.5 mol to about 6 mol of said deodorizing compound per mol of said cyclodextrin; The deodorizing solution has a pH greater than 9 and less than 12.5; The deodorizing compound is A blend of citral and coconut fragrance oil. A blend of d-limonene and coconut fragrance oil, A blend of citral and d-limonene, and A blend of octanol and d-limonene, A blend of compounds selected from the group consisting of Before applying the deodorizing solution to the substrate, the deodorizing solution is mixed at a temperature of 20° C. or higher to form a dispersion containing a complex of the cyclodextrin and the deodorizing compound; and 10. The substrate of claim 1, wherein the substrate exhibits an increase in moisture content of less than 1.7% by weight as a result of application of the odor eliminating solution onto the substrate.

14. An article comprising the substrate of claim 1.

15. A method for producing an odor-eliminating substrate, comprising the steps of: a) providing a substrate; b) forming a deodorizing solution comprising water, a cyclodextrin, a deodorizing compound, a stabilizing additive, and optionally a polar organic solvent; The deodorizing solution formed in step b) is a dispersion containing a complex of the cyclodextrin and the deodorizing compound; c) applying the deodorizing solution onto the substrate to obtain the deodorized substrate; where After c), the deodorizing base material contains at least 0.2 kg of the deodorizing compound per 1000 kg of the deodorizing base material; and The method, wherein, as a result of application of the odor eliminating solution onto the substrate, the substrate exhibits an increase in moisture content of less than 1.7% by weight.

16. A substrate having an applied deodorizing solution, The deodorizing solution is Water, Cyclodextrin, A deodorizing compound; A polar organic solvent; where The substrate comprises at least 0.2 kg of the deodorizing compound per 1000 kg of the substrate.

17. 17. The substrate of claim 16, wherein the substrate exhibits an increase in moisture content of less than 1% by weight as a result of application of the odor eliminating solution onto the substrate.

18. The substrate is Fluff pulp in the form of compressed sheets or in the form of airlaid fibers; Spunbond or carded nonwovens, woven fabrics, or solid materials of synthetic or cellulosic fibers; or Absorbent articles, where: When the substrate is a solid material, the solid material is selected from the group consisting of polymer foam, leather, and plastic film; and 17. The substrate of claim 16, wherein the substrate material is the absorbent article, the absorbent article being an adult incontinence pad, a feminine hygiene pad, a pull-up undergarment, an adult brief, a baby diaper, or a bed pad.

19. 17. The substrate of claim 16, wherein the polar organic solvent is selected from the group consisting of glycerol, propylene glycol, polypropylene glycol, polyethylene glycol, and mixtures thereof.

20. 17. The substrate of claim 16, wherein the cyclodextrin is unsubstituted or substituted α-cyclodextrin, β-cyclodextrin, or γ-cyclodextrin.

21. The deodorizing compound is an essential oil selected from the group consisting of citral, limonene, octanol, lavandin, geranium, grapefruit, linalool, citronellol, linalyl acetate, geraniol, eugenol, floracetate, cardamom, eucalyptus, juniper berry, lavender, lemon verbena, lemongrass, patchouli, rose, spearmint, tea tree, oregano, persimmon, and mixtures thereof; plant extracts, an odor eliminating material selected from the group consisting of benzaldehyde, cinnamaldehyde, ligustral, flurhydral, and mixtures thereof; or an antimicrobial agent selected from the group consisting of eucalyptus, lavender, thyme, peppermint, cajeput, cinnamon, clove, sage, tea tree oil, and mixtures thereof; The substrate of claim 16, wherein the substrate is at least one of:

22. 17. The substrate of claim 16, wherein the deodorizing solution comprises 1.5 mol to 1.75 mol of the deodorizing compound per 1 mol of the cyclodextrin.

23. 17. The substrate of claim 16, wherein the deodorizing solution has a pH of 12.0 or greater.

24. 17. An article comprising the substrate of claim 16.

25. A method for producing an odor-eliminating substrate, comprising the steps of: a) providing a substrate; b) applying a deodorizing solution onto the substrate to obtain the deodorized substrate; where The deodorizing solution is A polar organic solvent; Water, Cyclodextrin, A deodorizing compound; and After b), the deodorizing base material comprises at least 0.2 kg of the deodorizing compound per 1000 kg of the deodorizing base material.

26. 26. The method of claim 25, wherein applying the deodorizing solution onto the substrate in b) increases the moisture content of the substrate by less than 1% by weight.

27. 26. The method of claim 25, wherein the deodorizing solution comprises 1.5 mol to 1.75 mol of the deodorizing compound per 1 mol of the cyclodextrin.

28. 26. The method of claim 25, wherein the deodorizing solution has a pH of 12.0 or greater.

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