JP7802582B2 - Manufacturing raw materials and method for manufacturing polyurethane foam - Google Patents

Description

The present invention relates to manufacturing raw materials and a method for manufacturing polyurethane foam.

In addition to water as the main blowing agent, the raw materials for low-density polyurethane foam also contain an auxiliary blowing agent. An example of an auxiliary blowing agent is dichloromethane (DCM). However, dichloromethane has been identified as being harmful to the environment and is carcinogenic to humans, and is designated as a specified chemical substance. For these reasons, alternative auxiliary blowing agents to dichloromethane are being considered.

One example of an auxiliary blowing agent being considered as a substitute for dichloromethane is liquefied carbon dioxide. However, when the reaction stock solution, which is a mixture of liquefied carbon dioxide and other polyurethane foam raw materials, is discharged after mixing, the pressure can be suddenly reduced, causing bumping. This is undesirable, as it results in the formation of large, coarse bubbles in the polyurethane foam produced from the reaction stock solution. Furthermore, because liquefied carbon dioxide has a low boiling point, storage and use require equipment compatible with high-pressure gas.

Patent Document 1 describes a liquefied carbon dioxide foaming device that can prevent bumping. The liquefied carbon dioxide foaming device is equipped with a mesh-type pressure-varying device that prevents bumping by gradually reducing the pressure of the liquefied carbon dioxide. However, when used to produce polyurethane foam containing a filler, the pressure-varying device can become clogged with filler, resulting in abnormal foaming. Fillers are powders added to impart functionality, such as flame retardants, pigments, antibacterial agents, and polymer particles in polymer polyols.

As an example of using another auxiliary blowing agent, Patent Document 2 describes a composition for producing polyurethane foam in which 10 to 30 parts by mass of liquid halogenated olefin is blended per 100 parts by mass of polyol. Paragraph 0033 of Patent Document 2 states that if the content of liquid halogenated olefin is less than 10 parts by mass per 100 parts by mass of polyol, the effect of the auxiliary blowing agent is not fully exerted, resulting in a high apparent density of the foam and a hard polyurethane foam.

European Patent Application Publication No. 1332857 International Publication No. 2018/225651

The objective of the present invention is to provide a raw material for producing polyurethane foam and a method for producing polyurethane foam that can produce polyurethane foam with excellent load-bearing performance without causing any defects and that has a low environmental impact.

According to one aspect of the present invention, there is provided a raw material for producing a polyurethane foam having a 40% ILD hardness of 100 N or greater , as measured by the method specified in JIS K 6400-2:2012 . The raw material for production includes a polyol, an isocyanate, a first blowing agent, and a second blowing agent. The polyol includes a polymer polyol containing a particulate polymer. The first blowing agent is water. The second blowing agent includes cis -1-chloro-3,3,3- trifluoropropene . The content of the second blowing agent in the raw material for production is 1 part by weight or more and less than 10 parts by weight per 100 parts by weight of the polyol.

According to another aspect of the present invention, there is provided a method for producing a polyurethane foam having a 40% ILD hardness of 100 N or more. The production method includes a step of foaming the above-described production raw materials.

The present invention provides raw materials for producing polyurethane foam and a method for producing polyurethane foam that can produce polyurethane foam with excellent load-bearing performance without causing any defects and that has a low environmental impact.

1 is an explanatory diagram showing the configuration of a production facility for producing polyurethane foam from production raw materials according to an embodiment. FIG. 2 is an explanatory diagram showing the configuration of a production facility for producing polyurethane foam from production raw materials according to a comparative example.

Embodiments will be explained below with reference to the drawings as appropriate. Note that common components throughout the embodiments will be assigned the same reference numerals, and duplicate explanations will be omitted. Furthermore, each figure is a schematic diagram intended to explain and facilitate understanding of the embodiments, and while the shape, dimensions, and ratios may differ in some places from the actual device, these can be appropriately modified in design, taking into account the following explanation and known technology.

Polyurethane foams are used in load-bearing applications such as mattresses. If the polyurethane foam's load-bearing capacity is insufficient, it may be unable to support the weight of the user when used as a mattress, resulting in a feeling of bottoming out. Furthermore, the raw materials used to manufacture polyurethane foams must have a low environmental impact and be less susceptible to defects during production.

The manufacturing raw material according to the embodiment is a raw material for producing a polyurethane foam having a 40% ILD hardness of 100N or greater. The manufacturing raw material includes a polyol, an isocyanate, a first blowing agent, and a second blowing agent. The first blowing agent is water. The second blowing agent includes at least one selected from the group consisting of trans-1-chloro-3,3,3-trifluoropropene and cis-1-chloro-3,3,3-trifluoropropene. The content of the second blowing agent in the manufacturing raw material is 1 part by weight or more and less than 10 parts by weight per 100 parts by weight of the polyol.

The raw materials for production contain polyol and isocyanate, which polymerize to produce polyurethane. The raw materials also contain a first blowing agent (water) and a second blowing agent. Therefore, foaming occurs simultaneously with the polyurethane polymerization reaction, forming polyurethane foam.

The density (apparent density) of polyurethane foam can be adjusted by adjusting the content of the first blowing agent in the manufacturing raw materials. For example, foaming manufacturing raw materials containing a large amount of the first blowing agent can produce a low-density polyurethane foam. However, if the content of the first blowing agent in the manufacturing raw materials is excessively high, the heat of reaction can become too great, and the polyurethane foam may burn during production. Therefore, there are limits to using only the first blowing agent to reduce the density of polyurethane foam. Because the manufacturing raw materials of this embodiment contain a second blowing agent in addition to the first blowing agent, the content of the first blowing agent can be kept low even when producing a low-density polyurethane foam, preventing the heat of reaction from becoming too great.

The second blowing agent contains at least one selected from the group consisting of trans-1-chloro-3,3,3-trifluoropropene (HFO1233zd(E)) and cis-1-chloro-3,3,3-trifluoropropene (HFO1233zd(Z)).

Neither trans-1-chloro-3,3,3-trifluoropropene nor cis-1-chloro-3,3,3-trifluoropropene is designated as a specified chemical substance. Therefore, the environmental impact of manufacturing raw materials containing these substances can be reduced.

In addition, trans-1-chloro-3,3,3-trifluoropropene has a boiling point of 19°C, while cis-1-chloro-3,3,3-trifluoropropene has a boiling point of 39°C. Therefore, the manufacturing raw materials according to this embodiment are less likely to bump. Therefore, when producing polyurethane foam, a pressure-varying device is not required, and problems such as clogging of the discharge outlet are less likely to occur.

The content of the second blowing agent in the manufacturing raw materials is preferably 1 part by weight or more and less than 10 parts by weight per 100 parts by weight of polyol. Manufacturing raw materials containing less than 10 parts by weight of the second blowing agent per 100 parts by weight of polyol are more likely to produce polyurethane foam with a 40% ILD hardness of 100N or more.

Polyurethane foam with a 40% ILD hardness of 100 N or more has excellent load-bearing performance. 40% ILD hardness can be measured in accordance with the measurement method specified in JIS K 6400-2:2012.

The manufacturing raw materials related to this embodiment will now be described in further detail.

The manufacturing raw materials according to this embodiment include a polyol, an isocyanate, a first blowing agent, and a second blowing agent. The manufacturing raw materials may be in a form in which the respective raw materials exist independently without being mixed together. Alternatively, the manufacturing raw materials may be in the form of a raw material mixture in which the respective raw materials are mixed together. In addition to the above raw materials, the manufacturing raw materials may further include a catalyst, a foam stabilizer, an additive, etc.

Each ingredient is explained below.

(Polyol)
Examples of the polyol include multifunctional polyols and polymer polyols. One or more types of polyols may be used.

Polymer polyol is a polyol in which solid particulate polymers are dispersed. The particulate polymers can further improve the hardness of polyurethane foams. The content of polymer polyol is preferably 5 to 100 parts by weight per 100 parts of the total weight of polyol. The median diameter of the particulate polymers contained in the polymer polyol is preferably 0.2 to 500 μm.

(Isocyanate)
As the isocyanate, for example, tolylene diisocyanate is preferably used. The amount of isocyanate blended into the raw materials for production is preferably an amount such that the isocyanate index (NCO index) of the entire raw materials for production is a value of 90 or more and 120 or less. The isocyanate index is an index of the reaction ratio between hydroxyl groups and isocyanate groups, and can be calculated using the following formula.

(First Blowing Agent)
The first blowing agent is water. The preferred range of the content of the first blowing agent in the raw materials for production is 4 parts by weight or more and 6 parts by weight or less per 100 parts by weight of polyol. When the content of the first blowing agent is 4 parts by weight or more per 100 parts by weight of polyol, the foaming effect is easily obtained. When the content of the first blowing agent is 6 parts by weight or less per 100 parts by weight of polyol, the reaction heat does not become too large.

(Second Blowing Agent)
The second blowing agent comprises at least one selected from the group consisting of trans-1-chloro-3,3,3-trifluoropropene (HFO1233zd(E)) and cis-1-chloro-3,3,3-trifluoropropene (HFO1233zd(Z)). In particular, cis-1-chloro-3,3,3-trifluoropropene has a high boiling point of 39°C and can therefore be stored and used in an environment of normal temperature and pressure. Therefore, it is more preferred because it does not require equipment for high-pressure gas and allows polyurethane foam to be produced easily and at low cost.

(catalyst)
The raw materials for production may further contain a catalyst. Examples of the catalyst include tin catalysts, amine catalysts, etc. The type of catalyst used may be one or more types.

(Additives)
The raw materials for production may further contain additives. Examples of additives include antioxidants, flame lamination modifiers, flame retardants, hygiene improvers, pigments, and natural products. Examples of flame retardants include melamine, urea, polyvinyl chloride (PVC), zinc oxide, antimony trioxide, expandable graphite, and phosphorus-based solid materials. Examples of hygiene improvers include antibacterial agents, antimite agents, antifungal agents, antiviral agents, and deodorizers. Examples of natural products include green tea powder, catechin, charcoal, needle leaf powder, and herbs. The type of additive used may be one or more types.

Incorporating additives into the manufacturing raw materials is preferable, as it allows the polyurethane foam to be given properties that correspond to the type of additive. For example, adding a flame retardant to the manufacturing raw materials can improve the flame retardancy of the polyurethane foam. Adding a hygiene improving agent can improve the hygiene of the polyurethane foam.

The preferred content of additives in the manufacturing raw materials varies depending on the type of additive. For example, the preferred content of antibacterial agent is 0.1 to 2 parts by weight per 100 parts by weight of polyol. The preferred content of green tea powder is 0.1 to 2 parts by weight per 100 parts by weight of polyol.

The additive may be in the form of a filler. Here, a filler is a powder added for purposes such as imparting functionality. The median diameter of the filler contained in the additive is preferably 0.2 μm or more and 500 μm or less. Examples of filler forms include an antibacterial agent made up of particles with a median diameter of 5 μm, green tea powder made up of particles with a median diameter of 50 μm, and needle leaf powder made up of particles with a median diameter of 300 μm.

(Foam stabilizer)
The type of foam stabilizer is not particularly limited, but may be a silicone-based foam stabilizer. In this case, the foam stabilizer has an increased foam-stabilizing ability, which makes it easier to retain the foaming gas generated by the reaction, thereby improving moldability.

The content of foam stabilizer in the manufacturing raw materials is, for example, in the range of 0.5 to 15 parts by weight per 100 parts by weight of polyol. If the content of foam stabilizer in the manufacturing raw materials is too low, it becomes difficult to retain the foaming gas that is generated, and moldability tends to deteriorate. The content of foam stabilizer in the manufacturing raw materials is preferably in the range of 1.0 to 3.0 parts by weight per 100 parts by weight of polyol.

(nitrogen gas)
The raw materials for production may be foamed in the presence of nitrogen gas. When comparing a polyurethane foam produced by foaming in the presence of nitrogen gas with a polyurethane foam produced without adding nitrogen gas, if the density of the polyurethane foam is the same, the polyurethane foam produced by foaming the raw materials for production in the presence of nitrogen gas will contain more small bubbles. Therefore, mixing and foaming the raw materials in the presence of nitrogen gas allows the production of a homogeneous polyurethane foam with fewer coarse bubbles.

(Method for producing polyurethane foam)
A method for producing polyurethane foam will now be described. Polyurethane foam can be produced, for example, by supplying raw materials at a desired ratio from a tank containing the raw materials to a mixer, mixing and stirring the materials, and then discharging the mixture from the discharge port of the mixer to cause foaming.

The raw materials may be stored in separate tanks. Alternatively, multiple types of raw materials may be mixed in advance and supplied from the tank in the form of a mixed liquid. The mixed liquid may consist of two or more raw materials. For example, raw materials such as polyol, catalyst, and foam stabilizer may be mixed in advance. Furthermore, solid raw materials may be dispersed in liquid raw materials such as polyol in advance and supplied from the tank in the form of a dispersion. The temperature and pressure inside the tank and piping may be adjusted according to the properties of each raw material, such as the boiling point and melting point.

The above-mentioned raw materials are mixed, and the raw material mixture is discharged from the mixer's outlet. The outlet is preferably equipped with a mesh for removing foreign matter. A conveyor may be provided in the direction of discharge. Furthermore, a process sheet may be continuously fed onto the conveyor. The process sheet may be, for example, a paper surface agent or a plastic film. With this configuration, the discharged raw material mixture moves on the conveyor, allowing for continuous foaming.

This allows for the production of slab-blown polyurethane foam.

The method for producing polyurethane foam using the manufacturing raw materials of this embodiment is described below with reference to Figure 1.

Figure 1 shows a schematic diagram of an example of a manufacturing facility for producing polyurethane foam from manufacturing raw materials according to an embodiment.

The manufacturing equipment includes a polyol supply unit 1, an isocyanate supply unit 2, a first auxiliary agent supply unit 3, a second auxiliary agent supply unit 4, a nitrogen gas supply unit 5, a first pipe 11, a second pipe 12, a third pipe 14, a first branch pipe 13, a second branch pipe 15, and a mixer 6.

The polyol supply unit 1 is connected to the mixer 6 via a first pipe 11. The first pipe 11 branches into a first branch pipe 13. The first branch pipe 13 is connected to the first auxiliary agent supply unit 3. The isocyanate supply unit 2 is connected to the mixer 6 via a second pipe 12. The second pipe 12 branches into a second branch pipe 15. The nitrogen gas supply unit 5 is connected to the second branch pipe 15. The second auxiliary agent supply unit 4 is connected to the mixer 6 via a third pipe 14.

The polyol supply unit 1 is configured to supply polyol to the first pipe 11. The polyol supply unit 1 can include, for example, one or more tanks that store polyol. Examples of polyols include those described above. When two or more types of polyols are supplied from the polyol supply unit 1, separate tanks may be used to store each type of polyol. Polyols containing polymer polyols are preferably maintained at 20°C or higher.

In addition to polyol, polyol supply unit 1 can also contain raw materials other than polyol. Examples of raw materials other than polyol include antibacterial agents and natural materials, which are listed as examples of additives. Polyol supply unit 1 can, for example, contain a dispersion prepared by dispersing raw materials other than polyol in polyol. This method is suitable, for example, when blending powdered raw materials such as fillers with manufacturing raw materials. The raw materials other than polyol dispersed in polyol can be one type or two or more types.

The isocyanate supply unit 2 is configured to supply isocyanate to the second pipe 12. For example, it may be equipped with one or more tanks for storing isocyanate.

The first auxiliary supply unit 3 is configured to supply the first auxiliary to the first branch pipe 13. Examples of the first auxiliary include additives, amine catalysts, foam stabilizers, first blowing agents, and second blowing agents. The first auxiliary supply unit 3 may, for example, be equipped with one or more tanks for storing the first auxiliary. When two or more types of first auxiliary are supplied from the first auxiliary supply unit 3, separate tanks may be used for each type of first auxiliary. The interior of a tank containing a first auxiliary with a low boiling point is preferably at high pressure or at a temperature lower than the boiling point of the raw material. The type of first auxiliary contained in the polyol supply unit 1 does not need to be contained in the first auxiliary supply unit 3.

The second auxiliary supply unit 4 is configured to supply the second auxiliary to the third pipe 14. An example of the second auxiliary is a catalyst. Examples of catalysts include those described above. The second auxiliary supply unit 4 can be equipped with, for example, one or more tanks for storing the second auxiliary. When two or more types of second auxiliary are supplied from the second auxiliary supply unit 4, separate tanks may be used for each type of second auxiliary. Among the second auxiliary, raw materials of the type stored in the first auxiliary supply unit 3 (e.g., amine catalyst) do not need to be stored in the second auxiliary supply unit 4.

The nitrogen gas supply unit 5 is configured to supply nitrogen gas to the second branch pipe 15. The nitrogen gas supply unit 5 can store, for example, nitrogen gas in a gaseous state.

The manufacturing equipment further includes a control unit (not shown). The control unit is configured to control the supply amount of each raw material, as well as the supply start and stop timings.

The process for producing polyurethane foam using the production equipment configured as described above is described below.

Polyol is supplied from polyol supply unit 1 into first pipe 11 and sent through first pipe 11 along the arrow. Furthermore, the first auxiliary agent is supplied from first auxiliary agent supply unit 3 into first branch pipe 13 and sent through first branch pipe 13 along the arrow, and then into first pipe 11. The polyol and first auxiliary agent are further sent through first pipe 11 along the arrow. Therefore, the polyol and first auxiliary agent are supplied in a mixed state from first pipe 11 to mixer 6.

Furthermore, isocyanate is supplied from isocyanate supply unit 2 into second pipe 12 and sent through second pipe 12 along the arrow. Nitrogen gas is also supplied from nitrogen gas supply unit 5 into second branch pipe 15, sent through second branch pipe 15 along the arrow, and then supplied into second pipe 12. Isocyanate and nitrogen gas are further sent through second pipe 12 along the arrow. Therefore, the isocyanate and nitrogen gas are supplied in a mixed state from second pipe 12 to mixer 6.

Furthermore, the second auxiliary agent contained in the second auxiliary agent supply unit 4 is supplied into the third pipe 14, sent along the arrow in the third pipe 14, and supplied to the mixer 6.

The mixer 6 mixes and stirs the raw materials supplied through the first pipe 11, second pipe 12, and third pipe 14, and discharges the raw material mixture from the discharge port 7. The discharged raw material mixture foams as a result of a polymerization reaction, forming polyurethane foam.

The first pipe 11, the second pipe 12, the third pipe 14, the first branch pipe 13, and the second branch pipe 15 may be pipes that are compatible with high-pressure gas. Pipes that are compatible with high-pressure gas can maintain the strength of the manufacturing equipment even if the internal pressure increases. Therefore, raw materials with low boiling points can be blended in a liquid state.

Examples will be described below.
The raw materials used in each of the examples and comparative examples are as follows.
Polyol 1: Actcoal T-3000S (manufactured by Mitsui Chemicals SKC Polyurethanes Co., Ltd.)
Polyol 2: Sannix FA-375 (manufactured by Sanyo Chemical Industries, Ltd.)
Polymer polyol: Sharpflow FS-7301 (manufactured by Sanyo Chemical Industries, Ltd.)
Isocyanate: Cosmonate T-80 (manufactured by Mitsui Chemicals SKC Polyurethanes Co., Ltd.)
Tin catalyst: KOSMOS T 9 (manufactured by Evonik Japan Co., Ltd.)
Amine catalyst 1: DABCO (registered trademark) 33 LV (manufactured by Evonik Japan Co., Ltd.)
Amine catalyst 2: DABCO (registered trademark) NE300 (manufactured by Evonik Japan Co., Ltd.)
Amine catalyst 3: TOYOCAT-NP (manufactured by Tosoh Corporation)
Foam stabilizer 1: Niax (registered trademark) silicone L-598 (manufactured by Momentive Performance Materials Japan, LLC)
Foam stabilizer 2: TEGOSTAB B 8228 (manufactured by Evonik Japan Co., Ltd.)
Foam stabilizer 3: VORASURF (registered trademark) SZ-1142 Fluid (manufactured by Dow-Toray Industries, Inc.)
Antioxidant: NIAX COLOR STABILIZER CS-17 (manufactured by Momentive Performance Materials Japan, LLC)
Frame lamination modifier: Niax (registered trademark) flame lamination additive FLE-500LF (manufactured by Momentive Performance Materials Japan, LLC)
Flame retardant: CR-504L (manufactured by Daihachi Chemical Industry Co., Ltd.)
First blowing agent: water (H ₂ O)
Second blowing agent 1: HFO1233zd(Z)/(cis-1-chloro-3,3,3-trifluoropropene, manufactured by UniPo Corporation)
Second blowing agent 2: HFO1233zd(E)/(trans-1-chloro-3,3,3-trifluoropropene, manufactured by UniPo Corporation)
Third blowing agent 3: methylene chloride (dichloromethane, manufactured by Shin-Etsu Chemical Co., Ltd.)
Third foaming agent 4: liquefied carbon dioxide gas (CO ₂ , manufactured by Air Water Carbonate Inc.)
Antibacterial agent: Bactekiller BM-102TG (median diameter: 5 μm, manufactured by Fuji Chemical Co., Ltd.)
Natural ingredients: Green tea powder (median diameter: 50 μm, manufactured by Takada Tea Garden Co., Ltd.)
The median particle size of the particulate polymer dispersed in the polymer polyol is 0.6 μm.

<Production of polyurethane foam>
(Examples 1, 3, 5, 7, 9, Comparative Examples 11 and 13)
Using the production equipment shown in FIG. 1, polyurethane foams were produced by the method described below.

The manufacturing equipment used in Figure 1 included a polyol supply unit 1 and a first auxiliary agent supply unit 3 each equipped with multiple tanks. Nitrogen gas was not used.

An antibacterial agent dispersion was prepared by dispersing the antibacterial agent in polyol 1. Also, a natural material dispersion was prepared by dispersing a natural material in polyol 1.

Polyol 1, polyol 2, polymer polyol, antibacterial agent dispersion, and natural material dispersion were stored separately in multiple tanks provided in polyol supply unit 1. The polymer polyol was maintained at 27°C. Polyol supply unit 1 was connected to first piping 11 so that raw materials could be supplied from each tank.

Isocyanate was stored in a tank provided in the isocyanate supply unit 2, and the isocyanate supply unit 2 was connected to the second pipe 12.

The first auxiliary agent supply unit 3 is equipped with multiple tanks each containing a separate amine catalyst 1, amine catalyst 2, amine catalyst 3, foam stabilizer 1, foam stabilizer 2, foam stabilizer 3, antioxidant, flame laminate modifier, flame retardant, first blowing agent, and second blowing agent 1. The first auxiliary agent supply unit 3 is connected to the first branch pipe 13 so that raw materials can be supplied from each tank.

The tin catalyst was stored in a tank provided in the second auxiliary agent supply unit 4, and the second auxiliary agent supply unit 4 was connected to the third pipe 14.

The manufacturing equipment was then operated, and raw materials were supplied to mixer 6 from polyol supply unit 1, isocyanate supply unit 2, first auxiliary supply unit 3, and second auxiliary supply unit 4. The blending amount of each raw material was controlled by the control unit so as to be the value shown in Tables 1 and 2. The values shown in Tables 1 and 2 represent the blending amount of each raw material in parts by weight, when the total blending amount of polyol 1, polyol 2, and polymer polyol is 100 parts by weight. In the tables, raw materials marked with "-" indicate that they were not blended.

The supplied raw materials were mixed and stirred in mixer 6. A process sheet was continuously fed onto a moving conveyor (not shown), and the raw material mixture was discharged from mixer 6's discharge outlet 7 onto the process sheet. A mesh (not shown) for removing foreign matter was installed at discharge outlet 7. By continuously discharging the raw material mixture and running the conveyor, the discharged raw material mixture was foamed while moving. In this manner, a foam was continuously molded. After foaming was completed, the process sheet was removed from the foam, yielding a polyurethane foam.

(Examples 2, 4, 6, 8, 10, Comparative Examples 12 and 14)
A polyurethane foam was produced using the production equipment shown in FIG. 1 used in Example 1, with the following modifications:

Instead of second blowing agent 1, second blowing agent 2 was placed in first auxiliary agent supply section 3. This allowed second blowing agent 2 to be supplied to first branch pipe 13. The temperature of second blowing agent 2 was also maintained at 10°C or below. Furthermore, the manufacturing equipment was designed to be compatible with high-pressure gas. Other than that, the configuration was the same as the manufacturing equipment shown in Figure 1 used in Example 1.

The blending amounts of each ingredient were controlled by the control unit to the values shown in Tables 1 and 2.

Other than the above, polyurethane foam was obtained in the same manner as in Example 1.

(Comparative Examples 1, 3, 5, 7, and 9)
A polyurethane foam was produced using the production equipment shown in FIG. 1 used in Example 1, with the following modifications:

The first auxiliary supply section 3 contained the third blowing agent 3 instead of the second blowing agent 1. This allowed the third blowing agent 3 to be supplied to the first branch pipe 13. The rest of the configuration was the same as the manufacturing equipment shown in Figure 1 used in Example 1.

The blending amounts of each ingredient were controlled by the control unit to the values shown in Tables 1 and 2.

Other than the above, polyurethane foam was obtained in the same manner as in Example 1.

(Comparative Examples 2, 4, 6, 8, and 10)
Using the production equipment shown in FIG. 2, polyurethane foams of Comparative Examples 2, 4, 6, 8 and 10 were produced by the method described below.

Figure 2 shows a schematic diagram of a manufacturing facility for producing polyurethane foam from manufacturing raw materials including a third blowing agent 4 (liquefied carbon dioxide gas).

In addition to the manufacturing equipment described with reference to FIG. 1, the manufacturing equipment shown in FIG. 2 further includes a liquefied carbon dioxide gas supply unit 8 and a third branch pipe 18 branching off from the first pipe 11. The liquefied carbon dioxide gas supply unit 8 is connected to the third branch pipe 18. The liquefied carbon dioxide gas supply unit 8 is configured to be able to supply liquefied carbon dioxide gas to the third branch pipe 18.

The manufacturing equipment shown in Figure 2 also includes a mixer 9 instead of mixer 6. Mixer 9 mixes and stirs the raw materials supplied through first pipe 11, second pipe 12, and third pipe 14, and discharges the raw material mixture from discharge port 10. Mixer 9 also includes a liquefied carbon dioxide gas bubbling device (not shown). The liquefied carbon dioxide gas bubbling device is equipped with a mesh-type gradual pressure change device, which allows the pressure of the raw material mixture to be gradually reduced. This prevents bumping caused by a sudden decrease in pressure of the raw material mixture during discharge.

In addition, the manufacturing equipment in Figure 2 is compatible with high-pressure gas. Therefore, liquefied carbon dioxide, which has a low boiling point, can be blended in liquid form.

The manufacturing equipment shown in Figure 2 was operated, and liquefied carbon dioxide gas was supplied from the liquefied carbon dioxide gas supply unit 8. The gas was sent through the third branch pipe 18 and the first pipe 11 along the arrows and then supplied to the mixer 9. Other raw materials were supplied to the mixer 9 from the polyol supply unit 1, the isocyanate supply unit 2, the first auxiliary agent supply unit 3, and the second auxiliary agent supply unit 4, respectively. The blending amounts of each raw material were controlled by the control unit to be the values shown in Tables 1 and 2. The supplied raw materials were mixed and stirred in the mixer 9. A process sheet was continuously fed onto a moving conveyor (not shown), and the raw material mixture was discharged from the discharge port 10 of the mixer 9 onto the process sheet. During discharge, the pressure of the raw material mixture was gradually reduced using a pressure-varying device. By continuously discharging the raw material mixture and running the conveyor, the discharged raw material mixture was foamed while moving. This method resulted in continuous molding of a foam. After foaming was completed, the process sheet was removed from the foam to obtain a polyurethane foam.

<Measurement>
The various polyurethane foams obtained as described above were measured for apparent density, 40% ILD hardness and load-bearing capacity.

(Method for measuring apparent density)
The apparent density was measured in accordance with the measurement method specified in JIS K 7222:2005.

(Method for measuring 40% ILD hardness)
The 40% ILD hardness was measured in accordance with the measurement method specified in JIS K 6400-2:2012.

(Method for measuring load-bearing capacity)
The load-bearing capacity of the polyurethane foam was measured by a sensory evaluation of the feeling of hitting the bottom. The polyurethane foams produced from the raw materials for production of the Examples and Comparative Examples were cut into samples of 200 cm length x 100 cm width x 7 cm thickness, each of which was used as a sample for each formulation.

The feeling of hitting the floor was evaluated when the subject assumed a sleeping position on the centre of a single layer of sample laid on the floor. The evaluation was carried out by 12 male and female subjects in two sleeping positions: lying on their back and on their side. The evaluation criteria for feeling of hitting the floor were: if the subject felt that they were touching the floor, they were given a score of 0, which was deemed "feeling of hitting the floor", if they felt that they were not touching the floor at all, they were given a score of 2, which was deemed "no feeling of hitting the floor", and if they felt that they were somewhere between "feeling of hitting the floor" and "no feeling of hitting the floor", they were given a score of 1, which was deemed "somewhat feeling of hitting the floor". The evaluation was carried out as an absolute evaluation, not a relative evaluation to other samples.

For each sample, the average score for the feeling of bottoming out when sleeping on one's back and the average score for the feeling of bottoming out when sleeping on one's side are shown in Tables 3 and 4. The load-bearing capacity was evaluated based on the average score for the feeling of bottoming out when sleeping on one's back. In Tables 3 and 4, a score of ◯ is given when the average score is 1 point or more, a △ is given when the average score is greater than 0 points but less than 1 point, and an × is given when the average score is 0 points.

[result]
The experimental results will be explained below with reference to Tables 1 to 4.

Examples 1 to 10 are manufacturing raw materials containing 1 part by weight or more but less than 10 parts by weight of second blowing agent 1 (cis-1-chloro-3,3,3-trifluoropropene) or second blowing agent 2 (trans-1-chloro-3,3,3-trifluoropropene) as the second blowing agent per 100 parts by weight of polyol. These manufacturing raw materials do not contain any specific chemical substances, so they have a low environmental impact. In addition, no clogging of the discharge outlet occurred during foaming. The polyurethane foams manufactured from the manufacturing raw materials of Examples 1 to 10 all had a 40% ILD hardness of 100 N or more.

The evaluation results for bottoming out in Tables 3 and 4 show that, overall, when sleeping on one's side, the average score for bottoming out was lower and the feeling of bottoming out tended to be greater compared to sleeping on one's back. However, for all polyurethane foams with a 40% ILD hardness of 100 N or greater, the average score for bottoming out was higher than that of Comparative Examples 11 to 14, both when sleeping on one's back and side. Therefore, it was clear that the polyurethane foams produced from the manufacturing raw materials of Examples 1 to 10 were polyurethane foams with a low bottoming out feeling and excellent load-bearing performance.

This is thought to be due to the fact that the amount of second blowing agent 1 (cis-1-chloro-3,3,3-trifluoropropene) or second blowing agent 2 (trans-1-chloro-3,3,3-trifluoropropene) in the manufacturing raw materials is 1 part by weight or more but less than 10 parts by weight. When the amount of second blowing agent 1 or second blowing agent 2 is less than 10 parts by weight, the apparent density of the polyurethane foam does not become too low, and the 40% ILD hardness is maintained at 100 N or more. This is thought to be why bottoming out is less likely to occur and load-bearing performance is good.

Therefore, it was revealed that the raw materials used in the examples are raw materials for producing polyurethane foam that can produce polyurethane foam with excellent load-bearing performance without causing any problems and that have a low environmental impact.

Comparative Examples 1, 3, 5, 7, and 9, which contained third blowing agent 3 (dichloromethane), contained specific chemical substances and therefore were manufacturing raw materials with a high environmental impact. Furthermore, Comparative Examples 2, 4, 6, 8, and 10, which contained third blowing agent 4 (liquefied carbon dioxide) and were manufactured using the manufacturing equipment shown in Figure 2, experienced a problem during production in which the pressure-varying device provided on the manufacturing equipment shown in Figure 2 clogged.

Even when the manufacturing raw materials contained second blowing agent 1 (cis-1-chloro-3,3,3-trifluoropropene) or second blowing agent 2 (trans-1-chloro-3,3,3-trifluoropropene), the polyurethane foams produced from the manufacturing raw materials of Comparative Examples 11 to 14, in which the blending amount of second blowing agent 1 or second blowing agent 2 was 10 parts by weight or more, had inferior load-bearing performance compared to the polyurethane foams produced from the manufacturing raw materials of the Examples.

As shown in Table 4, in Comparative Examples 11 to 14, the 40% ILD hardness of the polyurethane foam was less than 100N. In the evaluation of bottoming out feeling, the polyurethane foams with a 40% ILD hardness of less than 100N had an average score of less than 1 in both the supine and side positions.

As mentioned above, in Comparative Examples 11 to 14, the content of the second blowing agent in the manufacturing raw materials was 10 parts by weight or more per 100 parts by weight of polyol. As a result, the 40% ILD hardness of the polyurethane foam was insufficient, and it was unable to support the load caused by the subject's weight, resulting in a strong feeling of bottoming out felt by the subject, which is thought to have resulted in a low evaluation of load-bearing performance.

In Examples 1, 2, 5-8 and Comparative Examples 1, 5, and 7, the manufacturing raw materials contained polymer polyol, but no clogging occurred during foaming. In contrast, clogging occurred at the discharge port in Comparative Examples 2, 6, and 8. The following is thought to be the cause. Comparative Examples 2, 6, and 8 contained a third blowing agent 4 (liquefied carbon dioxide) in addition to the polymer polyol, and were manufactured using the manufacturing equipment shown in Figure 2. Therefore, it is thought that the particulate polymer clogged the pressure-varying device provided in the manufacturing equipment shown in Figure 2.

In Examples 3 to 6, 9, and 10, the manufacturing raw materials contained antibacterial agents or natural materials as additives, but no clogging occurred during foaming. In particular, in Examples 5 and 6, the manufacturing raw materials contained natural materials with a large median diameter of 50 μm, but they were able to foam without any problems. In contrast, in Comparative Examples 4, 6, and 10, which contained antibacterial agents or natural materials as additives and third foaming agent 4 (liquefied carbon dioxide), clogging occurred in the pressure gradual change device.

Compare Examples 1, 3, 5, 7, and 9 with Examples 2, 4, 6, 8, and 10. When producing Examples 2, 4, 6, 8, and 10, it was necessary to manage the pressure and temperature of Second Blowing Agent 2 (trans-1-chloro-3,3,3-trifluoropropene). This required equipment for high-pressure gas. In contrast, Examples 1, 3, 5, 7, and 9 contained Second Blowing Agent 1 (cis-1-chloro-3,3,3-trifluoropropene), which has a high boiling point of 39°C, and therefore could be produced at room temperature and pressure. This eliminated the need for equipment for high-pressure gas. This allowed for production using simpler equipment, which was advantageous in terms of cost.

As described above, the manufacturing method of Examples 1 to 10, which includes a step of foaming the manufacturing raw materials, is a method that can produce polyurethane foams with excellent load-bearing performance without causing any defects and has a low environmental impact.

The present invention is not limited to the above-described embodiments, and various modifications can be made in the implementation stage without departing from the spirit of the invention. Furthermore, the various embodiments may be implemented in appropriate combinations, in which case the combined effects can be obtained. Furthermore, the above-described embodiments include various inventions, and various inventions can be extracted by combining selected elements from the multiple elements disclosed. For example, if the problem can be solved and the desired effect can be obtained even if some elements are deleted from all elements shown in the embodiments, the configuration from which these elements are deleted can be extracted as an invention.

1...Polyol supply section, 2...Isocyanate supply section, 3...First auxiliary agent supply section, 4...Second auxiliary agent supply section, 5...Nitrogen gas supply section, 6, 9...Mixer, 7, 10...Discharge port, 8...Liquefied carbon dioxide gas supply section, 11...First pipe, 12...Second pipe, 13...First branch pipe, 14...Third pipe, 15...Second branch pipe, 18...Third branch pipe.

Claims (3)

A raw material for producing a polyurethane foam having a 40% ILD hardness of 100 N or more as measured by the measurement method specified in JIS K 6400-2:2012 ,
The manufacturing raw materials include a polyol, an isocyanate, a first blowing agent, and a second blowing agent;
the polyol comprises a polymer polyol containing a particulate polymer;
the first blowing agent comprises water;
the second blowing agent comprises cis -1-chloro-3,3,3- trifluoropropene ;
The content of the second blowing agent in the manufacturing raw material is 1 part by weight or more and less than 10 parts by weight per 100 parts by weight of the polyol. The raw material for production according to claim 1 , further comprising at least one additive selected from the group consisting of a flame retardant, a hygiene improving agent, and a natural product. A method for producing a polyurethane foam having an ILD hardness of 100 N or more, comprising a step of foaming the raw material for production according to claim 1 or 2 .