JP7439318B2 - polyurethane foam - Google Patents

Description

An object of the present invention is to provide a polyurethane foam that has good drying properties after washing.

Polyurethane foam is formed from a polyurethane foam composition containing a polyol component, an isocyanate, and a blowing agent, and is frequently used as a material for bedding, clothing, and the like (Patent Documents 1, 2, and 3).

Japanese Patent Application Publication No. 2005-270146 JP2019-17948A JP2019-203061A

However, since polyurethane foam has a fine cell structure, it has a problem of high water retention and poor drying properties after washing.

An object of the present invention is to provide a polyurethane foam that has good drying properties after washing.

The present invention features polyurethane foams having a biomass degree of 24% or more as measured by ASTM D6866-20.

Since the polyurethane foam of the present invention has a biomass degree of 24% or more as measured by ASTM D6866-20, it has good drying properties after washing.
Biomass degree refers to the proportion of naturally derived raw materials contained in a product, and by measuring how much radioactive carbon C14, which is only contained in naturally derived substances, is contained in the product, the biomass degree of the product can be determined. It can be measured.
The degree of biomass in the present invention is determined by measuring the C14 concentration of polyurethane foam using accelerator mass spectrometry (AMS method) based on ASTM D6866-20, and calculating the ratio (%) to the C14 concentration of the current 100% naturally derived material. It is required by

It is a table showing the measurement results of the formulation, physical properties, and drying properties after washing of each Example of the present invention and each Comparative Example. It is a table showing the contents of each course of the washability test. It is a table showing the results of a drying test.

The polyurethane foam of the present invention has a biomass degree of 24% or more as measured by accelerator mass spectrometry (AMS method) based on ASTM D6866-20, so it has good drying properties after washing and shortens drying time. can do.

Polyurethane foams come in rigid, semi-rigid, and flexible types, and are selected depending on the application. For example, flexible polyurethane foam is often used for bedding such as mattresses and clothing such as bra pads. The polyurethane foam of the present invention includes any of rigid, semi-rigid, and flexible polyurethane foams.

The polyurethane foam of the present invention is obtained from a polyurethane foam composition containing a polyol component, a polyisocyanate, and a blowing agent. In the polyurethane foam composition, the polyol component and polyisocyanate react with each other by mixing and stirring, and the polyurethane foam is foamed to form a polyurethane foam.

The polyol component includes polyol, which is a compound having two or more hydroxyl groups in one molecule. The polyol component includes a plant-derived polyol. Plant-derived polyols are polyols produced using plant-derived raw materials, such as vegetable oils.

Examples of vegetable oils include castor oil, sunflower oil, rapeseed oil, linseed oil, cottonseed oil, tung oil, coconut oil, poppy oil, corn oil, soybean oil, and the like. Among them, castor oil polyol produced using castor oil as a raw material is a suitable example of a plant-derived polyol.

The castor oil polyol may be either a modified castor oil polyol or an unmodified castor oil polyol, or may contain both.
Modified castor oil polyol is a transesterification product between castor oil and fats and oils other than castor oil, a transesterification product between castor oil and fat and oil fatty acids, a transesterification product between castor oil and a polyhydric alcohol, and a transesterification product between castor oil and fatty acids. Esterification reaction products with polyhydric alcohols, esterification reaction products between some of the hydroxyl groups contained in castor oil and monocarboxylic acids such as acetic acid, reaction products obtained by addition polymerization of alkylene oxide to these, and addition polymerization products of these with hydrogen. Examples include hydrogen additives.
Examples of unmodified castor oil polyols include refined castor oil polyols, semi-refined castor oil polyols, unrefined castor oil polyols, and the like.

The plant-derived polyol preferably has a functional group number of 2 to 3.5, a hydroxyl value of 40 to 180 mgKOH/g, and a molecular weight of 724 to 2931, and one or more types may be used.
The amount of plant-derived polyol is determined so that the degree of biomass measured by ASTM D6866-20 is 24% or more, and is preferably 15 parts by mass or more, more preferably 30 parts by mass in 100 parts by mass of the polyol component. The amount is more preferably 80 parts by mass or more. The polyol component may include a polyol derived from petroleum oil. Including petroleum-derived polyol improves moldability and productivity.

The petroleum-derived polyol may be any polyether polyol, polyester polyol, polyether ester polyol, etc., and one or more of these may be used.

Examples of polyether polyols include polyhydric alcohols such as ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, butylene glycol, neopentyl glycol, glycerin, pentaerythritol, trimethylolpropane, sorbitol, and sucrose, as well as ethylene oxide and propylene. Examples include polyether polyols to which alkylene oxides such as oxides are added.

Examples of polyester polyols include polycondensation of aliphatic carboxylic acids such as malonic acid, succinic acid, and adipic acid, aromatic carboxylic acids such as phthalic acid, and aliphatic glycols such as ethylene glycol, diethylene glycol, and propylene glycol. Examples include polyester polyols obtained by
Further, examples of the polyether ester polyol include those obtained by reacting a polyether polyol with a polybasic acid to form a polyester, or those having both polyether and polyester segments in one molecule.

The petroleum-derived polyol preferably has a functional group number of 2.0 to 3.5, a hydroxyl value of 15 to 1000 mgKOH/g, and a molecular weight of 100 to 10,000.

The polyisocyanate is not particularly limited, and may be aromatic, alicyclic, or aliphatic, and may be a bifunctional isocyanate having two isocyanate groups in one molecule, or a difunctional isocyanate having two isocyanate groups in one molecule. It may be a trifunctional or higher functional isocyanate having three or more isocyanate groups, and they may be used alone or in combination.

Examples of the difunctional polyisocyanate include 2,4-tolylene diisocyanate (2,4-TDI), 2,6-tolylene diisocyanate (2,6-TDI), m-phenylene diisocyanate, p-phenylene diisocyanate, 4,4'-diphenylmethane diisocyanate (4,4'-MDI), 2,4'-diphenylmethane diisocyanate (2,4'-MDI), 2,2'-diphenylmethane diisocyanate (2,2'-MDI), Aromatic compounds such as diisocyanate, 3,3'-dimethyl-4,4'-biphenylene diisocyanate, 3,3'-dimethoxy-4,4'-biphenylene diisocyanate, cyclohexane-1,4-diisocyanate, Alicyclic ones such as isophorone diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, and methylcyclohexane diisocyanate; aromatic ones such as butane-1,4-diisocyanate, hexamethylene diisocyanate, isopropylene diisocyanate, methylene diisocyanate, and lysine diisocyanate. I can list the following. Note that diphenylmethane diisocyanate (MDI) may be used in combination with a plurality of types of polymeric MDI and prepolymers of polymeric MDI.

Examples of trifunctional or more functional polyisocyanates include 1-methylbenzole-2,4,6-triisocyanate, 1,3,5-trimethylbenzole-2,4,6-triisocyanate, and biphenyl-2,4,4'- Triisocyanate, diphenylmethane-2,4,4'-triisocyanate, methyldiphenylmethane-4,6,4'-triisocyanate, 4,4'-dimethyldiphenylmethane-2,2',5,5'tetraisocyanate, triphenyl Methane-4,4',4''-triisocyanate and the like can be mentioned.

The isocyanate index (INDEX) is preferably 70 to 150, more preferably 80 to 130, and most preferably 90 to 120. When the isocyanate index is less than 70, foam moldability becomes poor. On the other hand, if the isocyanate index exceeds 150, the foam becomes too hard and brittle, resulting in poor durability. The isocyanate index is the value obtained by dividing the number of moles of isocyanate groups in the polyisocyanate by the total number of moles of active hydrogen groups such as hydroxyl groups in the polyol component and water as a blowing agent, multiplied by 100. equivalent/active hydrogen equivalent x 100].

Examples of the blowing agent include water, hydrocarbons, halogen compounds, etc., and one or more of these may be used. Examples of hydrocarbons include cyclopentane, isopentane, normal pentane, and the like. Examples of the halogen compounds include methylene chloride, trichlorofluoromethane, dichlorodifluoromethane, nonafluorobutyl methyl ether, nonafluorobutyl ethyl ether, pentafluoroethyl methyl ether, heptafluoroisopropyl methyl ether, and the like. Among these, water is particularly suitable as a blowing agent. The water may be ion-exchanged water, tap water, distilled water, or the like. The amount of water as a blowing agent is 0.5 to 10 parts by weight, preferably 1 to 8 parts by weight, more preferably 1.5 to 5 parts by weight, based on 100 parts by weight of the polyol component. .

A catalyst and an auxiliary agent are appropriately added to the polyol composition as other components.
The catalyst is not particularly limited, and any catalyst known for use in polyurethane foams can be used. Usable catalysts include, for example, amine catalysts such as triethylamine, triethylenediamine, and tetramethylguanidine, tin catalysts such as dibutyltin dilaurate and stannath octoate, and metal catalysts such as phenylmercury propionate or lead octate. (Also called organometallic catalysts.) The total blending amount of the catalyst is appropriately determined depending on the type of catalyst, but is generally 0.01 to 3.0 parts by mass, preferably 0.02 to 1.5 parts by mass, per 100 parts by mass of the polyol component. parts, more preferably 0.05 to 1.2 parts by mass.

Examples of the auxiliary agents include foam stabilizers, crosslinking agents, coloring agents, flame retardants, antibacterial agents, stabilizers, and plasticizers.

As the foam stabilizer, those known for polyurethane foam can be used, and examples thereof include silicone foam stabilizers, fluorine-containing compound foam stabilizers, and surfactants. Particularly suitable are silicone foam stabilizers. Silicone foam stabilizers include those mainly composed of siloxane chains, those with a linear structure of siloxane chains and polyether chains, those with branched structures, and those with polyether chains modified in a pendant form on siloxane chains. etc.

Examples of the crosslinking agent include polyhydric alcohols such as ethylene glycol, diethylene glycol, glycerin, butanetetraol, and polyoxypropylene glycol, diethanolamine, and polyamines, and these can be used alone or in combination of two or more types.

Polyurethane foams include slab foam products and mold foam products, and the polyurethane foam of the present invention may be either of them.
A slab foam product is one in which a polyurethane foam composition is mixed and stirred, discharged onto a conveyor, foamed on the conveyor to continuously form a polyurethane foam, and then cut into a predetermined size. On the other hand, a molded foam product is made by injecting a polyurethane foam composition into a mold and foaming it, and has an outer shape that corresponds to the inner surface shape of the mold.

Further, the polyurethane foam of the present invention may have a cell membrane that has not been subjected to membrane removal treatment, or may have a cell membrane that has been subjected to membrane removal treatment to remove the cell membrane.
Film removal treatment is a well-known treatment for removing the cell membrane of polyurethane foam, and includes a method in which the polyurethane foam is immersed in an alkaline solution to melt the cell membrane, or a method in which the polyurethane foam is placed in an airtight container and exposed to oxygen, etc. There is a method of filling a closed container with combustible gas and then igniting it to cause an explosion and destroy the cell membrane.

Examples of the present invention will be specifically described along with comparative examples. The polyurethane foam compositions of each Example and each Comparative Example, in which the following raw materials were mixed as shown in the table of FIG. 1, were stirred and mixed and foamed to produce polyurethane foams of each Example and each Comparative Example. Note that Comparative Example 1 and Examples 1 to 3 are slab foam products, and Comparative Example 2 and Example 4 are mold foam products. Further, in Example 2, the polyurethane foam of Example 1 was subjected to membrane removal treatment by explosion to remove the cell membrane, and was the same as Example 1 except for the presence or absence of the cell membrane.

<Polyol component>
・Plant-derived polyol 1: Unmodified (refined) castor oil polyol, 100% vegetable content, number of functional groups 2.7, hydroxyl value 160 mgKOH/g, molecular weight 947, product name: H-30, manufactured by Ito Oil Co., Ltd. ・Plant-derived Polyol 2: 100 parts by mass of purified castor oil and 10.9 parts by mass of sebacic acid are reacted with stirring, and is a 100% vegetable-based castor oil polyol consisting of purified castor oil/sebacic acid = 2/1 mole. , functional group number 3.5, hydroxyl value 86mgKOH/g, molecular weight 2182
・Petroleum-derived polyol 1: Number of functional groups: 3, hydroxyl value: 24.1 mgKOH/g, molecular weight: 6983.4, product name: KC737, manufactured by Sanyo Chemical Industries, Ltd. ・Petroleum-derived polyol 2: Number of functional groups: 3, hydroxyl value: 56.1 mgKOH/ g, molecular weight 3000, product name: EP505S, manufactured by Mitsui Chemicals Co., Ltd. Petroleum-derived polyol 3; polyether polyol, number of functional groups 3, hydroxyl value 56.1 mgKOH/g, molecular weight 3000, product name: GP-3050NS, Sanyo Chemical Industries, Ltd. Company-made - Petroleum-derived polyol 4; number of functional groups: 3, hydroxyl value: 31 mgKOH/g, molecular weight: 5429, product name: Y-7530, manufactured by Mitsui Chemicals SKC Polyurethane Co., Ltd.

<Crosslinking agent>
・Diethylene glycol <foaming agent>
・Water <Amine catalyst>
・Amine catalyst 1: Aliphatic tertiary amine composition, product name: DABCO 33LSI, manufactured by Evonik Japan Co., Ltd. ・Amine catalyst 2: Product name: 2Mabs, manufactured by Nippon Nyukazai Co., Ltd. <Foam stabilizer>
・Foam stabilizer 1: Silicone type, product name: SZ1136, manufactured by Dow Corning Toray Co., Ltd. ・Foam stabilizer 2: Silicone type, product name: L-594Plus, manufactured by Evonik Japan Co., Ltd. ・Foam stabilizer 3: Silicone type, Product name: L3184J, manufactured by Momentive Performance Materials Japan LLC <Metal catalyst>
- Stanus octoate, product name: MRH-110, manufactured by Johoku Kagaku Kogyo Co., Ltd.

<Polyisocyanate>
・Polyisocyanate 1: Toluene diisocyanate with 2,4-TDI/2,6-TDI=80/20, product name: Coronate T-80, manufactured by Tosoh Corporation ・Polyisocyanate 2: 2,4-TDI/2, 6-TDI = 65/35 toluene diisocyanate, product name: Coronate T-65, manufactured by Tosoh Corporation - Polyisocyanate 3; Monomeric MDI (mixture of 4,4'-MDI and 2,4-MDI. 2, 4-MDI ratio is 25-50%)

The degree of biomass, physical properties, and drying properties after washing were measured for the polyurethane foams of each Example and each Comparative Example. The measurement results are shown in Figure 1.
The biomass degree (plant degree) indicates both a value measured by accelerator mass spectrometry (AMS method) and a calculated value based on ASTM D6866-20.
ASTM D6866 stipulates that the carbon-14 concentration in the atmospheric carbon-14 concentration in 1950 is measured using standard materials and materials, and the ratio thereof is defined as the biomass degree. However, since the current concentration of carbon-14 in the atmosphere is increasing year by year, it is stipulated that this value be multiplied by a coefficient for correction. In the calculation according to ASTM D6866-20, the degree of biomass was calculated using the 2020 atmospheric correction factor REF (pMC) = 100.0.
The degree of biomass was evaluated by the value measured by the AMS method. The evaluation criteria were "◎" if the measured value by AMS method was 50% or more, "○" if it was 24 to less than 50%, and "x" if it was less than 24%.
The calculated value is calculated using the formula: Biomass degree = Number of added parts of vegetable polyol / (Total number of added parts - Gas loss)
Calculated by gas loss=number of parts of water added/18×44.
In the above gas loss calculation formula, "18" is the molecular weight of water, and "44" is the molecular weight of carbon dioxide.

Regarding physical properties, density (JIS K7222), 25% hardness (JIS K6400-2 6.7D method), number of cells (JIS K6400-1), air permeability (JIS K6400-7 A method), tensile strength (JIS K6400 -5 5), elongation (JIS K6400-5 5), tear strength (JIS K6400-5 6B), dry heat strain (JIS K6400-4 4.5.2A method), and rebound (JIS K6400-3) .

The drying property after washing is determined by measuring the water absorption rate after washing, the water absorption rate after dehydration, and the water absorption rate after 24 hours drying using the following method.Based on each measurement result, the water absorption rate after washing, the dehydration rate after washing, and the water absorption rate after washing are evaluated. Post-drying performance evaluation and post-washing drying performance comprehensive evaluation were conducted. In addition, compared to slab foam products, mold foam products have a skin layer that makes it difficult for water to escape, so the evaluation of water absorption after washing, dehydration after washing, drying after washing, and overall evaluation of drying after washing are as follows: The tests were conducted separately for slab foamed products and molded foamed products.

The water absorption rate after washing was determined by sequentially carrying out the first washing course, second washing course, and third washing course shown in Fig. 2 for the samples of each example and each comparative example using a vertical washing machine. After each washing course, the weight of the sample was measured and the water absorption rate was calculated, and the value of the water absorption rate after the third washing course was taken as the post-washing water absorption rate. The water absorption rate after each washing course is calculated using the following formula.
Water absorption rate (%) = (Weight of sample after each washing cycle - Weight of sample before washing) / (Weight of sample before washing) x 100
Figure 3 shows the water absorption rate values for each time. Note that "before washing" means before the start of the first washing course.
The water absorbency after washing was evaluated based on the following criteria. Regarding Comparative Example 1 and Examples 1 to 3 of slab foam products, if the water absorption rate after washing is less than 160%, mark it as "◎", if it is between 160% and less than 200%, mark it as "○", and if it is 200% or more, mark as "×". ”. For Comparative Example 2 and Example 4 of the molded foam products, if the water absorption rate after washing was less than 95%, it was rated "◎", if it was 95 to less than 100%, it was rated "○", and if it was 100% or more, it was rated "x".

To calculate the water absorption rate after dehydration, after completing the third washing course, perform the first dehydration course and second dehydration course shown in Figure 2 in order, and after each dehydration course, measure the weight of the sample and calculate the water absorption rate. The water absorption rate after the second dehydration course was defined as the water absorption rate after dehydration. The water absorption rate after each dehydration course is calculated using the following formula.
Water absorption rate (%) = (Weight of sample after each dehydration course - Weight of sample before washing) / (Weight of sample before washing) x 100
Figure 3 shows the water absorption values after each dehydration course.
The dehydration property after washing was evaluated based on the following criteria. For Comparative Example 1 and Examples 1 to 3 of foamed slab products, if the water absorption rate after dehydration is less than 120%, mark it as "◎", if it is from 120 to less than 185%, mark it as "○", or if it is 185% or more, mark as "×". ”. For Comparative Example 2 and Example 4 of the molded foam products, the water absorption rate after dehydration was rated "◎" if it was less than 90%, "○" if it was 90 to less than 95%, and "x" if it was 95% or more.

The water absorption rate after 24-hour drying was determined by leaving the sample after the second dehydration course at room temperature (20 to 28°C is referred to as room temperature) for 24 hours, and then calculating the water absorption rate from the weight of the sample. The water absorption rate after drying for 24 hours is determined by the following formula.
Water absorption rate (%) after drying for 24 hours = (weight of sample after being left for 24 hours) / (weight of sample before washing) x 100
Figure 3 shows the water absorption values after drying for 24 hours.
The drying performance after washing was evaluated based on the following criteria. For Comparative Example 1 and Examples 1 to 3 of foamed slab products, if the water absorption rate after 24 hours drying is less than 1%, mark it as "◎", if it is between 1% and less than 3%, mark it as "○", if it is 3% or more I marked it with an “×”. For Comparative Example 2 and Example 4 of molded foam products, if the water absorption rate after 24 hours drying is less than 5%, it is marked "◎", if it is 5 to less than 10%, it is marked "○", and if it is 10% or more, it is marked "x". did.

Comprehensive laundry/drying performance evaluation is given as "◎" if the post-washing water absorption evaluation, post-washing dehydration evaluation, and post-washing drying evaluation consist of only "◎" or only "◎" and "〇". ”, and if all of the water absorption evaluation after washing, the evaluation of water dehydration after washing, and the evaluation of drying after washing are “〇”, the overall evaluation of washing drying property is “〇”. If there is even one "x" in the post-washing drying performance evaluation, the overall washing/drying performance evaluation was set as "x".

<Results of Comparative Example 1 and Examples 1 to 3 of foamed slab products>
・Comparative example 1
Comparative Example 1 is an example in which the polyol component is 100 parts by mass of petroleum-derived polyol 3 and 0 parts by mass of vegetable oil-derived polyol.
Comparative Example 1 has a biomass degree of 1% according to the AMS method, a biomass degree evaluation of “x”, a calculated biomass degree of 0%, a water absorption rate after washing of 248.4%, a water absorption evaluation after washing of “x”, and after dehydration. The water absorption rate was 193.3%, the dehydration performance after washing was evaluated as "x", the water absorption rate after 24 hour drying was 3.95%, the evaluation of drying performance after washing was "x", and the overall evaluation of drying performance after washing was "x".

・Example 1
Example 1 is an example in which the polyol components were composed of 60 parts by mass of plant-derived polyol 1, 20 parts by mass of vegetable oil-derived polyol 2, and 20.45 parts by mass of petroleum-derived polyol 3.
In Example 1, the biomass degree according to the AMS method is 58%, the biomass degree evaluation is "◎", the calculated biomass degree is 53%, the water absorption rate after washing is 169.9%, the water absorption evaluation after washing is "○", and after dehydration. Water absorption rate is 137.0%, water absorption rate after washing is ``○'', water absorption rate after 24 hour drying is 0.06%, drying rate after washing is ``◎'', water absorption rate after washing, water absorption rate after spin drying, and 24 hours. Both water absorption rates after drying were smaller than those of Comparative Example 1, and the overall evaluation of drying properties after washing was "◎".

・Example 2
Example 2 is an example in which a polyurethane foam formed from a polyol composition having the same formulation as in Example 1 was subjected to membrane removal treatment to remove the cell membrane.
Example 2 shows the same physical properties and biomass degree as Example 1 with the same polyol composition formulation, with a biomass degree of 57% according to the AMS method, a biomass degree evaluation of "◎", and a calculated biomass degree of 53. %Met.
Example 2 has a water absorption rate of 136.0% after washing, a water absorption rating of "◎" after washing, a water absorption rate of 107.2% after dehydration, a water absorption rating of "◎" after washing, and a water absorption rate of 0.06 after drying for 24 hours. %, and the post-washing drying property evaluation was “◎”, and the post-washing water absorption rate, the water absorption rate after dehydration, and the water absorption rate after 24-hour drying were all smaller than Comparative Example 1, and the post-washing drying property evaluation was “◎”. Met. In addition, since the cell membrane of the polyurethane foam was removed, the water absorption rate after washing and the water absorption rate after dehydration were smaller than in Example 1, and the drying performance was improved.

・Example 3
Example 3 is an example in which the polyol component was composed of 37 parts by mass of plant-derived polyol 1 and 63 parts by mass of petroleum-derived polyol 4.
Example 3 has a biomass degree of 28% according to the AMS method, a biomass degree evaluation of “〇”, a calculated biomass degree of 26%, a water absorption rate after washing of 197.1%, a water absorbency evaluation after washing of “〇”, and after dehydration. Water absorption rate is 184.7%, water absorption rate after washing is ``○'', water absorption rate is 1.77% after drying for 24 hours, drying rate is ``○'' after washing, water absorption rate after washing, water absorption rate after drying, and 24 hours. All of the water absorption rates after drying were smaller than those of Comparative Example 1, and the overall evaluation of drying properties after washing was "○".

<Results of Comparative Example 2 and Example 4 of molded foam products>
・Comparative example 2
Comparative Example 2 is an example in which the polyol component is composed of 70 parts by mass of petroleum-derived polyol 1, 10 parts by mass of petroleum-derived polyol 2, and 20 parts by mass of petroleum-derived polyol 3, and the vegetable oil-derived polyol is 0 parts by mass.
Comparative Example 2 has a calculated biomass degree of 0%, a water absorption rate after washing of 115.6%, a water absorption rating after washing of "x", a water absorption rate of 96.4% after dehydration, a dehydration rating of "◎" after washing, The water absorption rate after drying for 24 hours was 13.7%, the drying performance after washing was evaluated as "x", and the overall evaluation of drying performance after washing was "x".

・Example 4
Example 4 is an example in which the polyol components were composed of 22 parts by mass of plant-derived polyol 1, 17 parts by mass of vegetable oil-derived polyol 2, 51 parts by mass of petroleum-derived polyol 1, and 10 parts by mass of petroleum-derived polyol 2. .
Example 4 has a biomass degree of 27% according to the AMS method, a biomass degree evaluation of “〇”, a calculated biomass degree of 23%, a water absorption rate after washing of 94.0%, a water absorbency evaluation after washing of “◎”, and after dehydration. Water absorption rate is 87.5%, water absorption rate after washing is ``◎'', water absorption rate is 4.1% after drying for 24 hours, drying rate is ``◎'' after washing, water absorption rate after washing, water absorption rate after spin drying, and 24 hours. Both of the water absorption rates after drying were smaller than those of Comparative Example 2, and the overall evaluation of drying properties after washing was "◎".

Thus, the polyurethane foam of the present invention has good drying properties after washing.
Note that the present invention is not limited to the embodiments, and can be modified without departing from the spirit of the invention.

The polyurethane foam of the present invention has good drying properties after washing, and can be used for items that are washed, such as bedding such as mattresses and pillows, furniture such as seat cushions, and clothing such as bra pads. can.

Claims (3)

In a polyurethane foam obtained from a polyurethane foam composition containing a polyol component, a polyisocyanate, and a blowing agent,
The polyol component includes multiple types of castor oil-derived polyols and multiple types of petroleum-derived polyols,
the polyisocyanate comprises a mixture of isomers of diphenylmethane diisocyanate;
A polyurethane foam characterized by having a biomass degree of 24% or more as measured by ASTM D6866-20. In a polyurethane foam obtained from a polyurethane foam composition containing a polyol component, a polyisocyanate, and a blowing agent,
The polyol component includes multiple types of castor oil-derived polyols and multiple types of petroleum-derived polyols,
The castor oil-derived polyol includes a reaction product of castor oil and sebacic acid,
The polyisocyanate includes 2,4- diphenylmethane diisocyanate,
A polyurethane foam characterized by having a biomass degree of 24% or more as measured by ASTM D6866-20. The polyurethane foam according to claim 1 or claim 2 ,
The water absorption rate after washing, water absorption rate after dehydration, and water absorption rate after 24 hours drying of the polyurethane foam were measured by the following measurement method:
When the polyurethane foam is a slab foam product, the water absorption rate after washing is less than 200%, the water absorption rate after dehydration is less than 185%, and the water absorption rate after drying for 24 hours is less than 3%,
When the polyurethane foam is a molded foam product, the polyurethane foam has a water absorption rate of less than 100% after washing, a water absorption rate of less than 95% after dehydration, and a water absorption rate of less than 10% after drying for 24 hours. .

The method for measuring the water absorption rate after washing is to use a vertical washing machine and perform the first washing course, second washing course, and third washing course shown in Table 1 on the polyurethane foam sample in order, and then wait until the end of each washing course. The weight of the sample was measured each time, the water absorption rate was calculated, and the value of the water absorption rate after the third washing course was taken as the water absorption rate after washing.
Water absorption rate after washing (%) = (Weight of sample after each washing course - Weight of sample before washing) / (Weight of sample before washing) x 100
The method for measuring the water absorption rate after dehydration is to perform the first dehydration course and second dehydration course shown in Table 1 in order after the third washing course, and measure the weight of the sample after each dehydration course to determine the water absorption. The water absorption rate after the completion of the second dehydration course was defined as the water absorption rate after dehydration.
Water absorption rate after dehydration (%) = (Weight of sample after each dehydration course - Weight of sample before washing) / (Weight of sample before washing) x 100
The water absorption rate after 24-hour drying is calculated by leaving the sample after the second dehydration course at room temperature for 24 hours (20 to 28°C is referred to as room temperature), and then calculating the water absorption rate after 24-hour drying from the weight of the sample. Calculated.
Water absorption rate after drying for 24 hours (%) = (Weight of sample after being left for 24 hours) / (Weight of sample before washing) x 100