Polyurethane foam and bedding

Abstract

To provide a low-density polyurethane foam that can be easily manufactured.SOLUTION: A polyurethane foam is obtained from a composition containing polyols and polyisocyanates. The polyols contain a plant-derived polyol. The hydroxyl value of the plant-derived polyol is 130 mg KOH / g or less. The density based on JIS K7222 of the polyurethane foam is 25 kg / m3 or less.SELECTED DRAWING: None

Description

[Technical Field]

[0001] The present disclosure relates to polyurethane foams. [Background technology]

[0002] Patent Document 1 discloses a polyurethane foam obtained from a composition containing a plant-derived polyol. There is also a demand for polyurethane foams for low-density applications. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 2011-202026 Summary of the Invention [Problem to be solved by the invention]

[0004] The polyurethane foam of Patent Document 1 uses a castor oil-derived polyol with a hydroxyl value of approximately 160 mgKOH / g as a raw material. The use of a polyol with a relatively high hydroxyl value tends to increase the internal heat generation temperature during foaming, making production difficult. Therefore, there is a demand for a low-density polyurethane foam that is easy to produce. The present disclosure has been made in view of the above circumstances, and has an object to provide a low-density polyurethane foam that can be easily produced. The present disclosure can be realized in the following forms. [Means for solving the problem]

[0005] [1] A polyurethane foam obtained from a composition containing polyols and polyisocyanates, The polyols contain a plant-derived polyol, The plant-derived polyol has a hydroxyl value of 130 mgKOH / g or less, Density based on JIS K7222 is 25 kg / m3 Below is polyurethane foam. [Effects of the Invention]

[0006] The present disclosure provides low density polyurethane foams that are easily manufactured. DETAILED DESCRIPTION OF THE INVENTION

[0007] Here, a preferred example of the present disclosure will be described.

[0008] [2] Polyurethane foam having an isocyanate index of 91 or more. [3] The polyurethane foam, wherein the polyols contain a petroleum-derived polyol, and the plant-derived polyol accounts for 75 parts by mass or less when the total of the petroleum-derived polyol and the plant-derived polyol is 100 parts by mass. [4] Polyurethane foam having a compression set of less than 8.5% in accordance with JIS K 6400-4 4.5.2. [5] Polyurethane foam having a resilience in accordance with JIS K 6400-3 of 25% or more and 45% or less. [6] Polyurethane foam for bedding.

[0009] The present disclosure will be described in detail below. In this specification, when a numerical range is indicated using "-", it is intended to include both the lower limit and the upper limit unless otherwise specified. For example, the expression "10-20" includes both the lower limit "10" and the upper limit "20". In other words, "10-20" has the same meaning as "10 or more and 20 or less".

[0010] 1. Polyurethane foam The polyurethane foam is obtained from a polyurethane resin composition (hereinafter also simply referred to as a composition) containing polyols and polyisocyanates. The polyols contain a plant-derived polyol. The polyols preferably contain a petroleum-derived polyol.

[0011] [Plant-derived polyol] The plant-derived polyol contains, for example, castor oil. In this disclosure, "castor oil" does not include modified castor oil and dehydrated castor oil, which will be described later. In this disclosure, "castor oil" means unmodified castor oil. Unmodified castor oil is extracted and refined from the seeds of the castor bean plant, which belongs to the Euphorbiaceae family, and has not been subjected to a cross-linking (modification) treatment with a dibasic acid or the like, or a dehydration treatment, which will be described later. Dehydrated castor oil is obtained by dehydrating castor oil (a non-drying oil) to produce a drying oil. Castor oil is an ester of fatty acids and glycerin. Castor oil contains ricinoleic acid as its main component, and other components include unsaturated fatty acids such as oleic acid, linoleic acid, and linolenic acid, and saturated fatty acids such as palmitic acid and stearic acid.

[0012] The plant-derived polyol may contain modified plant-derived oil as a component using the plant-derived oil, and an example of the modified plant-derived oil is modified castor oil.

[0013] Modified plant-derived oils, such as modified castor oil, are prepared by mixing a dibasic acid and a plant-derived oil to achieve the desired properties and then subjecting them to a dehydration-condensation reaction. Known methods can be used to synthesize these modified plant-derived oils. For example, a plant-derived oil is dissolved in a solvent and then a dibasic acid is added. The reaction mixture is refluxed using a Dean-Stark trap, and the resulting water is removed from the system during the dehydration-condensation reaction. After the reaction is complete, the solvent is removed under reduced pressure to obtain the desired compound.

[0014] Examples of dibasic acids include aliphatic dibasic acids, alicyclic dibasic acids, aromatic dibasic acids, and mixtures thereof. Examples of aliphatic dibasic acids include sebacic acid, oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pimelic acid, suberic acid, azelaic acid, undecanedioic acid, dodecanedioic acid, brassylic acid, tetradecanedioic acid, pentadecanedioic acid, thapsic acid, heptadecanedioic acid, octadecanedioic acid, nonadecanedioic acid, eicosane diacid, docosane diacid, tetracosane diacid, hexacosane diacid, octacosane diacid, maleic acid, fumaric acid, citraconic acid, itaconic acid, mesaconic acid, muconic acid, and mixtures thereof.

[0015] Examples of the alicyclic dibasic acid include cyclopentanedicarboxylic acid, cyclohexanedicarboxylic acid, decalindicarboxylic acid, tetrahydrophthalic acid, himic acid, and mixtures thereof.

[0016] Examples of aromatic dibasic acids include terephthalic acid, isophthalic acid, phthalic acid, bibenzoic acid, tolylenedicarboxylic acid, xylinedicarboxylic acid, naphthalenedicarboxylic acid, biphenylenedicarboxylic acid, diphenylsulfonedicarboxylic acid, diphenyletherdicarboxylic acid, diphenoxyethanedicarboxylic acid, diphenylketonedicarboxylic acid, phenylindanedicarboxylic acid, and mixtures thereof.

[0017] Furthermore, a hydroxy dibasic acid containing a hydroxyl group in the molecule can also be used as the dibasic acid, such as tartronic acid, isomalic acid, hydroxymethylmalonic acid, dihydroxymalonic acid, malic acid, itamaric acid, citramalic acid, methylmalic acid, ethylmalic acid, dimethylmalic acid, trimethylmalic acid, tartaric acid, 2,2-dihydroxysuccinic acid, methyltartaric acid, dimethyltartaric acid, hydroxyglutaric acid, dihydroxyglutaric acid, trihydroxyglutaric acid, hydroxyadipic acid, dihydroxyadipic acid, hydroxypimelic acid, dihydroxypimelic acid, hydroxysuberic acid, hydroxyazelaic acid, dihydroxyazelaic acid, hydroxysebacic acid, dihydroxysebacic acid, hydroxydodecanedioic acid, dihydroxydodecanedioic acid, hydroxybrassylic acid, hydroxytetradecanedioic acid, dihydroxyhexadecanedioic acid, hydroxyoctadecanedioic acid, dihydroxyoctadecanedioic acid, furoic acid, hydroxyecanedio ... Examples include icosane diacid, dihydroxyeicosane diacid, dihydroxyfumaric acid, dihydroxymaleic acid, hydroxycitraconic acid, hydroxymuconic acid, hydroxycyclopentanedicarboxylic acid, hydroxycyclohexanedicarboxylic acid, hydroxytetrahydrophthalic acid, hydroxyterephthalic acid, dihydroxyterephthalic acid, hydroxyisophthalic acid, dihydroxyisophthalic acid, hydroxyphthalic acid, dihydroxyphthalic acid, coccinic acid, hydroxynaphthalenedicarboxylic acid, dihydroxynaphthalenedicarboxylic acid, hydroxydiphenylsulfonedicarboxylic acid, meconic acid, and mixtures thereof.

[0018] The dibasic acid preferably includes sebacic acid, which is a plant-derived dibasic acid.

[0019] From the viewpoint of environmental friendliness, the plant-derived polyol is preferably more than 0 parts by mass, more preferably 30 parts by mass or more, and even more preferably 40 parts by mass or more, when the total of the petroleum-derived polyol and the plant-derived polyol is 100 parts by mass. From the viewpoint of ensuring strength, the plant-derived polyol is preferably 75 parts by mass or less, more preferably 65 parts by mass or less, and even more preferably 55 parts by mass or less, when the total of the petroleum-derived polyol and the plant-derived polyol is 100 parts by mass. From these viewpoints, the plant-derived polyol is preferably more than 0 parts by mass but not more than 75 parts by mass, more preferably 30 parts by mass or more and 65 parts by mass or less, and even more preferably 40 parts by mass or more and 55 parts by mass or less, when the total of the petroleum-derived polyol and the plant-derived polyol is 100 parts by mass.

[0020] From the viewpoint of promoting the reaction, the hydroxyl value of the plant-derived polyol is preferably 40 mgKOH / g or more, more preferably 60 mgKOH / g or more, and even more preferably 80 mgKOH / g or more. From the viewpoint of suppressing heat generation during foaming, the hydroxyl value of the plant-derived polyol is 130 mgKOH / g or less, preferably 115 mgKOH / g or less, and more preferably 100 mgKOH / g or less. From these viewpoints, the hydroxyl value of the plant-derived polyol is 40 mgKOH / g or more and 130 mgKOH / g or less, preferably 60 mgKOH / g or more and 115 mgKOH / g or less, and more preferably 80 mgKOH / g or more and 100 mgKOH / g or less. Note that the hydroxyl value of a mixture obtained by mixing two or more plant-derived polyols is the value of the mixture as a whole.

[0021] [Petroleum-derived polyol] The petroleum-derived polyol is not particularly limited. When the total of the petroleum-derived polyol and the plant-derived polyol is 100 parts by mass, the petroleum-derived polyol is preferably more than 0 parts by mass, more preferably 20 parts by mass or more, and even more preferably 40 parts by mass or more, from the viewpoint of ensuring strength. When the total of the petroleum-derived polyol and the plant-derived polyol is 100 parts by mass, the petroleum-derived polyol is preferably 80 parts by mass or less, more preferably 70 parts by mass or less, and even more preferably 60 parts by mass or less, from the viewpoint of environmental friendliness. From these viewpoints, when the total of the petroleum-derived polyol and the plant-derived polyol is 100 parts by mass, the petroleum-derived polyol is preferably more than 0 parts by mass and 80 parts by mass or less, more preferably 20 parts by mass or more and 70 parts by mass or less, and even more preferably 40 parts by mass or more and 60 parts by mass or less.

[0022] Examples of petroleum-derived polyols include polyether polyols, polymer polyols, and polyester polyols.

[0023] Examples of polyether polyols include polyether polyols obtained by adding alkylene oxides such as ethylene oxide (EO) and propylene oxide (PO) to polyhydric alcohols such as ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, butylene glycol, neopentyl glycol, glycerin, pentaerythritol, trimethylolpropane, sorbitol, and sucrose.

[0024] The polyether polyol is preferably a polyether polyol having a weight average molecular weight of 500 to 8000 (preferably 800 to 5000, more preferably 1000 to 3000) and a functionality of 2 to 6 (preferably 2 or 3).

[0025] As the polymer polyol, for example, a polymer polyol obtained by graft copolymerizing a vinyl monomer such as acrylonitrile and styrene into a polyether polyol having two or three functional groups as the base polyol can be suitably used. Examples of the base polyol include polyether polyols containing PO units (propylene oxide units) and EO units (ethylene oxide units) as AO units (alkylene oxide units). The weight average molecular weight of the polymer polyol refers to the weight average molecular weight of the base polyol.

[0026] Examples of polyester polyols that can be used include polycaprolactone-based polyester polyols and adipate-based polyester polyols. Examples of polycaprolactone-based polyester polyols include polyester polyols obtained by ring-opening addition polymerization of lactones such as ε-caprolactone. Examples of adipate-based polyester polyols include polyester polyols obtained by polycondensation of polyfunctional carboxylic acids and polyfunctional hydroxy compounds. Polyester polyols also have the effect of making the cells of polyurethane foam finer and more uniform.

[0027] [Other polyols] The polyol may contain other polyols in addition to the above polyols. The other polyols may be any polyols that are generally used in polyurethane foams, without any particular limitation.

[0028] In the present disclosure, when low molecular weight polyhydric alcohols such as ethylene glycol, diethylene glycol, triethylene glycol, propylene glycol, dipropylene glycol, 1,3-butanediol, 1,4-butanediol, glycerin, trimethylolpropane, pentaerythritol, and sorbitol are used, these polyhydric alcohols are also included in the polyols.

[0029] [Polyisocyanates] Polyisocyanates are compounds having multiple isocyanate groups, and examples thereof include aromatic isocyanates such as tolylene diisocyanate (TDI), 4,4-diphenylmethane diisocyanate (MDI), 1,5-naphthalene diisocyanate (NDI), triphenylmethane triisocyanate, and xylylene diisocyanate (XDI); alicyclic isocyanates such as isophorone diisocyanate (IPDI) and dicyclohexylmethane diisocyanate; aliphatic isocyanates such as hexamethylene diisocyanate (HDI); free isocyanate prepolymers obtained by reacting these with polyols; and modified isocyanates such as carbodiimide-modified isocyanates. These polyisocyanates may be contained alone or in combination of two or more.

[0030] The polyisocyanates may be any of aromatic, alicyclic, and aliphatic isocyanates, and may also be bifunctional isocyanates having two isocyanate groups in one molecule, or trifunctional or higher isocyanates having three or more isocyanate groups in one molecule, and these may be used alone or in combination. For example, bifunctional isocyanates include 2,4-tolylene diisocyanate (TDI), 2,6-tolylene diisocyanate (TDI), m-phenylene diisocyanate, p-phenylene diisocyanate, 4,4'-diphenylmethane diisocyanate (MDI), 2,4'-diphenylmethane diisocyanate (MDI), 2,2'-diphenylmethane diisocyanate (MDI), xylylene diisocyanate, 3,3'-dimethyl-4,4'-biphenylene diisocyanate, 3,4 ... Examples of isocyanates include aromatic isocyanates such as 1,3'-dimethoxy-4,4'-biphenylene diisocyanate, alicyclic isocyanates such as cyclohexane-1,4-diisocyanate, isophorone diisocyanate, dicyclohexylmethane-4,4'-diisocyanate, and methylcyclohexane diisocyanate, and aliphatic isocyanates such as butane-1,4-diisocyanate, hexamethylene diisocyanate, isopropylene diisocyanate, methylene diisocyanate, and lysine isocyanate. Examples of isocyanates with two or more functionalities include polymethylene polyphenylisocyanate (polymeric MDI). Examples of tri- or higher functional isocyanates include 1-methylbenzene-2,4,6-triisocyanate, 1,3,5-trimethylbenzene-2,4,6-triisocyanate, biphenyl-2,4,4'-triisocyanate, diphenylmethane-2,4,4'-triisocyanate, methyldiphenylmethane-4,6,4'-triisocyanate, 4,4'-dimethyldiphenylmethane-2,2',5,5'tetraisocyanate, and triphenylmethane-4,4',4"-triisocyanate. The number of isocyanates is not limited to one, but may be two or more. For example, one aliphatic isocyanate and two aromatic isocyanates may be used in combination.

[0031] The isocyanate index is the equivalent ratio of isocyanate groups in polyisocyanates to reactive groups, such as hydroxyl groups, in polyols that can react with isocyanate. Therefore, a value less than 100 means that reactive groups, such as hydroxyl groups, are in excess of isocyanate groups, while a value greater than 100 means that isocyanate groups are in excess of reactive groups, such as hydroxyl groups. From the viewpoint of reaction stability, the isocyanate index (INDEX) of polyisocyanates is preferably 91 or more, more preferably 93 or more, and even more preferably 95 or more. From the viewpoint of suppressing heat generation during foaming, the isocyanate index (INDEX) of polyisocyanates is preferably 125 or less, more preferably 115 or less, and even more preferably 110 or less. From these viewpoints, the isocyanate index (INDEX) of polyisocyanates is preferably 91 or more and 125 or less, more preferably 93 or more and 115 or less, and even more preferably 95 or more and 110 or less.

[0032] [catalyst] The composition preferably contains a catalyst. The catalyst primarily promotes the urethane reaction between the polyols and the polyisocyanates. Examples of the catalyst include known catalysts commonly used in polyurethane foams, such as tertiary amines (e.g., triethylenediamine, N,N-dimethylaminoethanol, 6-dimethylamino-1-hexanol, and N,N',N'-trimethylaminoethylpiperazine), organometallic compounds (e.g., stannous octoate and stannous octoate), acetates, and alkali metal alcoholates.

[0033] The catalyst content in the composition is preferably 0.1 to 5.0 parts by mass, based on 100 parts by mass of the total of the petroleum-derived polyol and the plant-derived polyol. A content of 0.1 parts by mass or more can sufficiently promote the urethanization reaction. A content of 5.0 parts by mass or less can prevent the formation of a non-uniform cell structure due to excessive promotion of the urethanization reaction.

[0034] [Foam stabilizer] The composition preferably contains a foam stabilizer. The foam stabilizer is not particularly limited. Examples of the foam stabilizer include silicone compounds such as organopolysiloxanes, organopolysiloxane-polyoxyalkylene copolymers, polyalkenylsiloxanes having polyoxyalkylene side chains, and silicone-grease copolymers; anionic surfactants such as sodium dodecylbenzenesulfonate and sodium lauryl sulfate; polyether siloxanes; and phenolic compounds. These foam stabilizers may be used alone or in combination of two or more. The amount of the foam stabilizer is not particularly limited. The amount of the foam stabilizer is preferably 0.03 parts by mass or more and 5.0 parts by mass or less, based on 100 parts by mass of the total of the petroleum-derived polyol and the plant-derived polyol.

[0035] [Foaming agent] The composition preferably contains a blowing agent. The blowing agent is not particularly limited. Suitable blowing agents include, for example, water, carbon dioxide gas, and hydrohaloolefins. When the blowing agent is water, the amount added is determined within a range that allows the polyurethane foam to have a desired density and a good foaming state, and is usually preferably 1 part by mass or more and 10 parts by mass or less, where the total amount of the petroleum-derived polyol and the plant-derived polyol is 100 parts by mass.

[0036] Examples of hydrohaloolefins include hydrofluoroolefins (HFOs), hydrochlorofluoroolefins (HCFOs), etc. The content of hydrohaloolefins is preferably more than 0 parts by mass and not more than 25 parts by mass, relative to 100 parts by mass of the total of the petroleum-derived polyol and the plant-derived polyol.

[0037] [Other ingredients] The composition may contain other components in addition to those described above as necessary. Examples of such other components include antioxidants, ultraviolet absorbers, thickeners, plasticizers, antibacterial agents, and colorants. Examples of antioxidants include dibutylhydroxytoluene and hindered phenol-based antioxidants. From the viewpoint of reducing the content of volatile organic compounds, it is particularly preferable to use hindered phenol-based antioxidants with a molecular weight of 300 or more. Examples of thickeners include calcium carbonate, aluminum hydroxide, and magnesium hydroxide.

[0038] 2. Density requirements For polyurethane foam, the density according to JIS K 7222 is 30 kg / m 3 Less than 27 kg / m 3 Less than 25 kg / m is more preferable. 3 More preferably, 24 kg / m 3 The following is particularly preferred: In polyurethane foam, the density according to JIS K 7222 is usually 5 kg / m 3 That's all.

[0039] 3. Requirements for Compression Set In polyurethane foams, the compression set according to JIS K 6400-4 4.5.2 A method is preferably less than 10%, more preferably less than 8.5%, and even more preferably less than 5%. In polyurethane foams, the compression set according to JIS K 6400-4 4.5.2 A method is usually 0.5% or more.

[0040] 4. Requirements for rebound resilience In polyurethane foams, the rebound resilience based on a rebound test in accordance with JIS K6400-3 is preferably 10% or more, more preferably 25% or more, and even more preferably 30% or more. In polyurethane foams, the rebound resilience based on a rebound test in accordance with JIS K6400-3 is preferably 80% or less, more preferably 60% or less, and even more preferably 45% or less. From these viewpoints, in polyurethane foams, the rebound resilience based on a rebound test in accordance with JIS K6400-3 is preferably 10% or more and 80% or less, more preferably 25% or more and 60% or less, and even more preferably 30% or more and 45% or less.

[0041] 5. Elongation requirements The elongation of the polyurethane foam in accordance with JIS K6400-5 5 is preferably 80% or more, more preferably 90% or more, and even more preferably 100% or more. The elongation of the polyurethane foam in accordance with JIS K6400-5 5 is usually 500% or less.

[0042] 6. Hardness requirements The hardness of the polyurethane foam according to JIS K6400-2 6.7 D method is preferably 20 N or more, more preferably 40 N or more, and even more preferably 60 N or more. The hardness of the polyurethane foam according to JIS K6400-2 6.7 D method is preferably 300 N or less, more preferably 200 N or less, and even more preferably 150 N or less. From these viewpoints, the hardness of the polyurethane foam according to JIS K6400-2 6.7 D method is preferably 20 N or more and 300 N or less, more preferably 40 N or more and 200 N or less, and even more preferably 60 N or more and 150 N or less.

[0043] 7. Ventilation requirements In polyurethane foams, the air permeability according to JIS K6400-7 is preferably 30 L / min or more, more preferably 40 L / min or more, and even more preferably 50 L / min or more. In polyurethane foams, the air permeability according to JIS K6400-7 is usually 300 L / min or less.

[0044] 8. Requirements regarding biomass content based on the blending ratio of raw materials The biomass degree based on the blending ratio of raw materials in a polyurethane foam (hereinafter also referred to as the biomass degree of raw materials) is calculated using the following formula (1). In formula (1), "the number of parts of plant-derived polyol added" refers to the total number of parts of all plant-derived polyols added when multiple types of plant-derived polyols are used. "The number of parts of plant-derived polyol added" includes the number of parts of unmodified castor oil, modified castor oil, and dehydrated castor oil added. In addition, in the "number of parts of plant-derived polyol added," if the plant-based content of the plant-derived polyol is less than 100%, the number of parts of the plant-derived polyol added is multiplied by the plant-based content. Here, the plant-based content refers to the proportion of plant-derived materials in the raw materials. In formula (1), "the total number of parts of polyurethane resin composition added" refers to the total number of parts of all raw materials included in the polyurethane resin composition added. "All raw materials" refers to plant-derived polyols, petroleum-derived polyols, catalysts, foam stabilizers, blowing agents, polyisocyanates, and other raw materials (crosslinking agents, antibacterial agents, pigments, flame retardants, etc.). The gas loss in formula (1) is calculated using formula (2) below when water is used as the blowing agent. In formula (2), "18" is the molecular weight of water, and "44" is the molecular weight of carbon dioxide. When the polyurethane resin composition contains HFO as a blowing agent, the biomass content of the polyurethane foam is calculated using formula (3) below, assuming that all of the HFO volatilizes during the reaction. The units for "parts of plant-derived polyol added," "total parts of polyurethane resin composition added," and "parts of HFO added" are parts by mass.

[0045]

number

[0046]

number

[0047]

number

[0048] In the polyurethane foam, the biomass content of the raw materials is preferably 20% or more, more preferably 25% or more, and even more preferably 30% or more.

[0049] 9. Requirements for biomass content under the AMS Act The biomass ratio of polyurethane foam is also determined by the value measured by accelerator mass spectrometry (AMS) based on ASTM D6866-21. The carbon-14 concentration of polyurethane foam is measured against a standard substance for atmospheric carbon-14 concentration in 1950, and the ratio is used to determine the biomass ratio. However, since the carbon-14 concentration in the atmosphere is currently increasing year by year, a coefficient is applied to the carbon-14 concentration value for correction. The biomass ratio is calculated according to ASTM D6866-21 using the atmospheric correction factor for 2021, REF(pMC) = 100.0.

[0050] The biomass degree of the polyurethane foam measured by the AMS method based on ASTM D6866-21 (hereinafter also referred to as the biomass degree by the AMS method) is preferably 20% or more, more preferably 25% or more, and even more preferably 30% or more.

[0051] 10. Polyurethane foam manufacturing method Polyurethane foam can be produced by a known foaming method in which a polyurethane resin composition is stirred and mixed to react a polyol and a polyisocyanate. Foaming methods include slab foaming and mold foaming, and either molding method may be used. Slab foaming is a method in which a mixed polyurethane resin composition is discharged onto a belt conveyor and foamed at atmospheric pressure and room temperature. On the other hand, mold foaming is a method in which a mixed polyurethane resin composition is filled into a mold (forming die) and foamed within the mold.

[0052] 11. Application of polyurethane foam Polyurethane foam is suitable for bedding. For example, polyurethane foam can be used for mattresses, quilts, mattress pads, pillows, etc. Furthermore, polyurethane foam can be used for cushioning materials, sound-absorbing materials, kitchen sponges, hydroponic cultivation media for plants, etc.

[0053] 12. Actions and Effects of the Present Embodiment In this embodiment, a low-density polyurethane foam having good foaming properties can be provided. In the polyurethane foam of this embodiment, the internal heat generation temperature during foaming can be reduced, making it easier to manufacture. In the polyurethane foam of this embodiment, the biomass content can be increased. The polyurethane foam of this embodiment can reduce the compression set. The polyurethane foam of this embodiment can have a large elongation. [Example]

[0054] Next, the above embodiment will be described in more detail with reference to examples and comparative examples. 1. Polyurethane foam manufacturing Polyurethane resin compositions were prepared according to the proportions shown in Tables 1 and 2, and polyurethane foams of Examples and Comparative Examples were produced by slab foaming.

[0055] [Table 1]

[0056] [Table 2]

[0057] In Tables 1 and 2, the numerical values ​​of each component without a unit, except for the indexes, represent parts by mass. Various information regarding petroleum-derived polyols 1-3 and plant-derived polyols 1 and 2 is shown in Table 3 below. Plant-derived polyol 2 is a 100% plant-based castor oil-derived polyol consisting of plant-derived polyol 1:sebacic acid = 2 mol:1 mol. Sebacic acid is a derivative of castor oil and is 100% plant-based. Plant-derived polyol 2 is a synthetic product produced by charging 100 parts by weight of plant-derived polyol 1 and 10.9 parts by weight of sebacic acid into a glass reactor equipped with a stirrer, temperature controller, etc., and reacting them while stirring for a specified time at a specified temperature. The "OHV" column in Table 3 indicates the hydroxyl value. In Example 2, the plant-derived polyol containing 20 parts by mass of plant-derived polyol 1 and 25 parts by mass of plant-derived polyol 2 had an OHV of 121.1 mgKOH / g. "Mw" indicates the weight-average molecular weight. "Mn" indicates the number-average molecular weight.

[0058] [Table 3]

[0059] The specific details of the catalyst, foam stabilizer, blowing agent, and polyisocyanate in Tables 1 and 2 are shown below. Catalyst 1: Aliphatic tertiary amine (Evonik Japan, DABCO 33LSI) Catalyst 2: Stannous octoate (manufactured by Johoku Chemical Industry Co., Ltd., MRH-110) Foam stabilizer: Organic silicone (Dow Corning Toray, SZ-1136) Foaming agent: Hydrofluoroolefin (Mitsui Chemours Fluoroproducts Co., Ltd., Opteon TM 1100 Foam Expansion Agent) Polyisocyanate: Toluene diisocyanate (TDI) 2,4 / 2,6 isomers in an 80 / 20 ratio (Tosoh Corporation, Coronate T-80)

[0060] 2. Evaluation Next, the polyurethane foams obtained in the examples and comparative examples were evaluated as follows.

[0061] [Biomass content based on raw material composition] The biomass ratio based on the blending ratio of raw materials was calculated using the above formulas (1)-(3). The calculation results are shown in the column "Biomass ratio of raw materials" in Tables 1 and 2.

[0062] [Biomass content by AMS method] Biomass ratio by the AMS method was determined by measurement using accelerator mass spectrometry (AMS) based on ASTM D6866-21. Biomass ratio was calculated using the atmospheric correction factor for 2021, REF(pMC) = 100.0. The calculation results are shown in the "Biomass ratio by AMS method" column in Tables 1 and 2.

[0063] [Foaming] The foaming properties of the polyurethane foam were evaluated according to the following criteria. "B": Good foaming. "C": Poor foaming.

[0064] [Internal temperature] The internal temperature of the polyurethane foam during foaming was evaluated according to the following criteria. "B": Less than 160°C "C": 160℃ or more

[0065] [density] The density of the polyurethane foam was determined by a measurement method conforming to JIS K 7222. The measurement results are shown in the "Density" column of Tables 1 and 2. The density of the polyurethane foam was evaluated according to the following criteria. "B": 25kg / m 3 below "C": 25kg / m 3 Greater than

[0066] [stretch] The elongation of the polyurethane foam was determined by a measurement method conforming to JIS K 6400-5 5. The measurement results are shown in the "Elongation" column of Tables 1 and 2. The elongation of the polyurethane foam was evaluated according to the following criteria. "A": 100% or more "B": 80% or more but less than 100% "C": Less than 80%

[0067] [Rebound elasticity] The impact resilience of the polyurethane foam was determined according to the method of JIS K 6400-3. The measurement results are shown in the "Impact Resilience" column of Tables 1 and 2. The impact resilience of the polyurethane foam was evaluated according to the following criteria. "A": 30% or more "B": 25% or more but less than 30% "C": Less than 25%

[0068] [Hardness] The hardness of the polyurethane foam was measured by a measurement method conforming to JIS K 6400-2 6.7 Method D. The measurement results are shown in the "Hardness" column of Tables 1 and 2. The hardness of the polyurethane foam was evaluated according to the following criteria. "B": 20N or more and 300N or less "C": Less than 20N or more than 300N

[0069] [Ventilation volume] The air permeability of polyurethane foam was measured by a method conforming to JIS K 6400-7. The measurement results are shown in the "Air Permeability" column of Tables 1 and 2. The air permeability of the polyurethane foam was evaluated according to the following criteria. "A": 50L / min or more "B": 30L / min or more and less than 50L / min "C": Less than 30L / min

[0070] [Compression set] The compression set of the polyurethane foam was determined by a measurement method conforming to JIS K 6400-4 4.5.2 Method A. The measurement results are shown in the "Compression set" column of Tables 1 and 2. The compression set of the polyurethane foam was evaluated according to the following criteria. "A": Less than 5% "B": 5% or more but less than 10% "C": 10% or more

[0071] [comprehensive evaluation] "A": None of the following evaluations are "C": "Foaming," "Internal temperature," "Density," "Elongation," "Rebound elasticity," "Hardness," "Ventilation," or "Compression set" "B": Any of the following is rated "C": "Foaming," "Internal temperature," "Density," "Elongation," "Rebound elasticity," "Hardness," "Air permeability," or "Compression set"

[0072] 3.Results In Examples 1-12 and Comparative Examples 1-3, the "density evaluation" was "B." In Examples 1-12 and Comparative Examples 1-3, the polyurethane resin composition contained a plant-derived polyol containing castor oil or modified castor oil, and the density was 25 kg / m 3 The values ​​were as low as

[0073] Examples 1-12 satisfy both of the following requirements (a) and (b): Comparative Examples 1 and 2 do not satisfy the following requirement (b); Comparative Example 3 does not satisfy the following requirement (a). Requirement (a): The hydroxyl value of the plant-derived polyol is 130 mg KOH / g or less. Requirement (b): When the total of the petroleum-derived polyol and the plant-derived polyol is 100 parts by mass, the plant-derived polyol is 75 parts by mass or less. In Examples 1-12, the "overall evaluation" was "A." In Examples 1-12, by satisfying the above requirements (a) and (b), the internal temperature of the polyurethane foam during foaming was reduced while the physical properties (rebound resilience, air permeability, and compression set) were improved.

[0074] 4. Effects of the Example According to the above examples, a low-density polyurethane foam having good foaming properties can be produced. The internal heat generation temperature during foaming could be kept low, making production easy. The biomass content of polyurethane foam was increased. The impact resilience of polyurethane foam was increased. The breathability of polyurethane foam was increased. The compression set of polyurethane foam was reduced.

[0075] The present disclosure is not limited to the above-described embodiments, and various modifications and variations are possible within the scope of the claims of the present disclosure.

Claims

1. obtained from a composition comprising polyols and polyisocyanates, The polyols include a plant-derived polyol and a petroleum-derived polyol, the amount of the plant-derived polyol is 75 parts by mass or less when the total amount of the petroleum-derived polyol and the plant-derived polyol is 100 parts by mass, The plant-derived polyol has a hydroxyl value of 130 mg KOH / g or less, Density based on JIS K7222 is 25 kg / m ３ 1. A polyurethane foam comprising: The following (A) and / or (B) are satisfied: (A) The compression set according to JIS K6400-4 4.5.2 A method is less than 8.5%. (B) The rebound resilience according to JIS K6400-3 is 25% or more and 45% or less. And, the polyurethane foam satisfies one or more of the following (C) to (G): (C) The ventilation rate according to JIS K6400-7 is 30 L / min or more. (D) The hardness according to JIS K6400-2 6.7 D method is 73N or more. (E) Elongation according to JIS K6400-5 5 is 80% or more (F) The compression set according to JIS K6400-4 4.5.2 A method is 4.0% or less. (G) Isocyanate index is 91 or more and 100 or less

2. 2. The polyurethane foam according to claim 1, having a rebound resilience in accordance with JIS K6400-3 of 25% or more and 45% or less.

3. Bedding comprising the polyurethane foam according to claim 1 or 2.

4. obtained from a composition comprising polyols and polyisocyanates, The polyols include a plant-derived polyol and a petroleum-derived polyol, the amount of the plant-derived polyol is 75 parts by mass or less when the total amount of the petroleum-derived polyol and the plant-derived polyol is 100 parts by mass, The plant-derived polyol has a hydroxyl value of 130 mg KOH / g or less, Density based on JIS K7222 is 25 kg / m ３ is as follows: Bedding comprising a polyurethane foam that satisfies the following (A) and / or (B): (A) The compression set according to JIS K6400-4 4.5.2 A method is less than 8.5%. (B) The rebound resilience according to JIS K6400-3 is 25% or more and 45% or less.

5. The polyurethane foam according to claim 1 , wherein the plant-derived polyol contains modified castor oil obtained by crosslinking unmodified castor oil with a dibasic acid.

6. The bedding according to claim 4, wherein the plant-derived polyol contains modified castor oil obtained by crosslinking unmodified castor oil with a dibasic acid.

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