JPS6215236A - Thermally reverse color changing polyurethane foam - Google Patents

Abstract

PURPOSE:A thermally reverse color changing polyurethane foam obtained by adding a thermally reverse color changing composition consisting of three components of an electron donative coloring dyestuff, acidic substance and solvent as a colorant to a polyol and polyisocyanate as a principal component. CONSTITUTION:A polyurethane foam produced by adding a thermally reverse color changing composition consisting of (A) an electron donative dyestuff, e.g. 3,3'-dimethoxyfluoran (yellow), (B) an acidic substance which is an electron donative substance capable of developing a color by binding to the component (A), preferably 1,2,3-triazole, and (C) a solvent, preferably one or more solvents selected from alcohols, esters, azomethines and amides having preferably >=150 deg.C boiling point under ordinary pressure in an amount of 1-50pts.wt., based on 100pts.wt. polyol, to a polyurethane raw material consisting essentially of the polyol and a polyisocyanate by using a foaming machine. The above-mentioned thermally reverse color changing composition is preferably added in the form of a material envelped in a microcapsule, alone or together with an ordinary dye or pigment thereto.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention has the property of reversibly changing color with heat,
The present invention provides a novel polyurethane foam that can provide a type of temperature sensor function to toys, ornaments, bath supplies, kitchen utensils, industrial materials, and the like.

[Prior Art] Conventionally, there are many types of commercially available foams, among which polyurethane foam is used as a cushioning agent in bedding, furniture, tools, vehicles, etc., and as a heat insulating material in buildings, machinery, home appliances, etc. It is also used as a water-absorbing material in miscellaneous goods, toys, cosmetic tools, etc., and its uses are wide-ranging. has been done.

By the way, the above polyurethane foam, especially toys, H
The polyurethane foam that makes up goods, cosmetics, etc.
Generally, these products are commercialized as cut products of the foam structure itself, and although they have a characteristic in that they can change their physical shape, in particular, when it comes to color, coloring agents are It merely had the color tone of the common dye and pigment itself. Therefore, if the colors of these products could sense temperature changes in the outside world and manifest a color change function in response to the changes, for example, the temperature-sensitive color change of kitchen utensils could produce effects such as being able to visually check the temperature of hot water in the kitchen. Although it is clear that this polyurethane foam can be expected to have excellent industrial applicability that has never been seen before, such a polyurethane foam has not been disclosed at all in the past.

[Problems to be Solved by the Invention] In view of the current situation, the present inventors have developed a method for producing polyols and polyurethane foams using existing foam forming equipment and various raw materials, and without impairing the various properties of urethane foams. Isocyanate is the main component, and various known additives,
For example, in addition to formulations consisting of a catalyst, a foam stabilizer, an extender pigment, a plasticizer, a blowing agent, a solvent, water, etc., thermoreversible color-changing compositions,
In particular, by adding the microcapsule granules of the w1 product or by using them together with ordinary dyes and pigments, a new polyurethane foam exhibiting extremely sensitive thermoreversible discoloration is obtained.

Thus, the aim is to dramatically expand the effectiveness and uses of polyurethane foam.

Means for Solving Problem E] The present invention provides a thermoreversible color-changing composition comprising three components: a polyol and a polyisocyanate as main components, an electron-donating color forming dye, an acidic substance, and a solvent as a coloring agent. It is characterized by being added alone or together with ordinary dyes and pigments. This relates to thermoreversibly color-changing polyurethane foam.

In this case, if the above-mentioned thermoreversible color-changing composition is configured so that the three components, electron-donating color-forming pigment, acidic substance, and solvent coexist as microcapsules, the bonding of the three components can be effectively achieved. This is a good reason for conservation.

As an acidic substance that is one component of the thermoreversible color-changing composition, l.
The use of 2.3 triazoles makes the effect of the thermoreversible color-changing composition even greater.

Next, as the solvent, which is another component forming the thermoreversible color-changing composition, one or more solvents selected from alcohols, esters, azomethines, and amides having a boiling point of 150°C or higher at room temperature are used. It is preferable to do so.

Solvents with a boiling point of 150°C or higher at room temperature generally volatilize easily and are difficult to coexist with the other two components, and their dissolving power is too high and the so-called desensitizing effect is too large, which is inconvenient. It is.

[Function] The color change mechanism of the thermoreversible color-changing composition consisting of the three components of electronic potato coloring pigments, an acidic substance, and a solvent in the present invention is as follows:
It is as follows.

That is, in a color-forming body in which the color-forming bond between an electron-donating color pigment and an acidic substance is relatively slow, when the solvent reaches an appropriate temperature, the bond between the two is destroyed by its dissolving action. Therefore, this action can be reversibly dissociated by a temperature difference,
In addition, the dissociation is approximately proportional to the melting point or boiling point in the case of solvents of the same series. In other words, a solvent with a high melting point breaks bonds at high temperatures and causes one color to disappear.

Incidentally, the details of the above discoloration mechanism are disclosed in Japanese Patent Application No. 55-153410 and Japanese Patent Application No. 60-584 filed by the same applicant as the present application.
81 and Japanese Utility Model Application No. 58-119417.

The solvents used in the present invention, especially alcohols, esters, azomethines, and amides with a boiling point of 150°C or higher at room temperature, are commonly in a solid state, and the solid has a high boiling point, melting point, or solidification point. The higher the temperature, the more it has the property of causing discoloration at high temperatures, and the lower the temperature, the more effective it is at low temperatures. Thus, the thermochromic temperature range of the present invention is about -4
It is possible to set various desired temperatures ranging from about 0°C to 150°C, and significant discoloration is observed above and below the set temperature, and the discoloration repeats reversibly.

[Example] Originally, polyurethane foams are divided into polyether-based polyurethane foams and polyester-based polyurethane foams, depending on the type of polyol (polyhydroxy compound) used as the main component, but the present invention applies to both polyurethane foams. can be applied.

Polyether polyols are, for example, polyhydroxyl compounds such as glycerin, trimethylolpropane, pentaerythritol, sorbitol, sage, ethylenediamine, diethylenetriamine, propylene oxide, etc.

It is obtained by ring-opening addition polymerization of tyrene oxide, etc. using an alkali catalyst, and any polyether polyol can be used, but for the production of flexible polyurethane foam, polyols with a hydroxyl value of 100 or less, and those with a hydroxyl value of 100 or less for rigid polyurethane foam are used. For production, those having a hydroxyl value of 100 or more are preferred.

Examples of polyester polyols include condensation polymers of dibasic acids such as adipic acid and phthalic acid and polyhydroxy compounds such as diethylene glycol, glycerin, and trimethylolpropane, and ring-opening polymers of ε-caprolactone. Can be used.

As the polyisocyanate which is another main component of the polyurethane foam, aliphatic polyisocyanates containing two or more isocyanate groups in the same molecule, aromatic polyisocyanates, or modified products thereof are used. Specifically, aliphatic incyanates include hexamethylene diisocyanate, isophorone diisocyanate, methylcyclohexane diisocyanate, etc., and aromatic incyanates include tolylene diisocyanate) (2,4- and/or 2,6- isomer), diphenyl diisocyanate, triphenyl diisocyanate, chlorophenyl-2,4-diisocyanate, P
Examples include -phenyl diisocyanate, xylene diisocyanate, diphenylmethane diisocyanate, naphthalene diisocyanate, and polyvalent polyisocyanates obtained by reacting a low polycondensate of aniline and formaldehyde with phosgene. Among these polyisocyanates, the isomer ratio of tolylene diisocyanate, that is, the mixing ratio (weight ratio) of 2.4 monomer and 2,6 monomer is 80.
: 20 to 65 : 35 and polyhydric polyisocyanates obtained by reacting a low polymer of aniline and formaldehyde with phosgene are generally highly useful and are easily available in N-valent form, so they are also economically viable. It's advantageous.

The amount of polyincyanate used relative to the total amount of polyhydroxyl compounds and other active hydrogen-containing compounds, that is, the incyanate index, is preferably in the range of 80 to 130, but within this range, it is also preferable in terms of the physical properties of the urethane foam. The range that gives results is Zoo to 115.

The blowing agent to be blended with the main component of the component includes water or a low boiling point volatile liquid. Examples of low-boiling volatile liquids include halogenated hydrocarbons such as trichloromonofluoromethane, dibromodifluoromethane, dichlorodifluoromethane, dichlorotetrafluoroethane, monochlorodifluoromethane, trifluoroethyl bromide, dichloromethane, and methylene chloride. These blowing agents can be used alone or in combination.

Examples of the catalyst added to the main component together with the blowing agent include triethylenediamine, N-methylmorpholine, tetramethyl-1,4-butanediamine, N-methylpiperazine, dimethylethanolamine, diethylethanolamine, and triethylamine. Amine compounds, or stannous octenoate, dibutyltin dilaurate.

Organometallic compounds such as dibutyltin di-2-ethylhexoate are used. These catalysts may be used alone or in combination of two or more. The amount of the catalyst used is not particularly limited and can be varied over a wide range, but is usually 0.005 to 2.0 parts by weight based on 100 parts by weight of the polyhydroxyl compound.

The foam stabilizer used together with the blowing agent, catalyst, etc. is a silicone foam stabilizer commonly used in the production of polyurethane foam, specifically, an organosiloxane-polyoxyalkylene copolymer or a polyoxyalkylene side chain. Examples include organosilicon surfactants such as polyalkenylsiloxane, and the amount used is in the range of 0.1 to 3.0 parts by weight per 100 parts by weight of the polyhydroxyl compound.
Among these, it is preferably 0.5 to 2.0 parts by weight.

Furthermore, in the present invention, in addition to the above-mentioned components, additives such as flame retardants, crosslinking agents, ##Size inhibitors, etc. may be added as necessary.

The thermoreversible color-changing composition constituting the main part of the present invention, which is used together with known raw materials for polyurethane foam, consists of three components: an electron-donating color-forming dye, an acidic substance, and a solvent. It is a mixture of components.

The electron-donating coloring dyes among these three components are those that control the color and are selected from a group of so-called heat-sensitive and pressure-sensitive dyes, such as 3.3゛dimethoxyfluorane. (yellow).

3, 3' dibutoxyfluorane (yellow), 3 chlor, 6 phenylaminofluorane (yellow-orange), 3 diethylamino,
6 methyl 7 chlorofluorane [flow value], 3 diethyl 7-8 benzofluorane (peach), 3 3° 3°'
Tris(p-dimethylaminophenyl)phthalide (purple blue)
, 3-3' bis(p-dimethylaminophenyl) phthalide (green), 3-diethylamino dibendylaminofluorane (dark green), 3-diethylamino+16methyl-77 enylaminofluorane (black).

Substituted phenylmethane and fluorane derivatives, such as
In addition, various indolylphthalide dyes (blue to green), spiropyrans (yellowish brown to reddish purple), etc. are mentioned. In the present invention, these may be used alone or in combination of two or more.

Examples of the acidic substance that is an electron-accepting substance that develops color by combining with the electron-donating color-forming substance include phenol, m-cresol, and p-cresol.

p-nonylphenol, 0-phenylphenol, p-
Phenylphenol, styrenated phenol, p-cumylphenol, P-octylphenol, bisphenol A, β-naphthol, le5 dihydroxynaphthalene,
resorcin, caterol, pyrogallol, phloroglucin, phloroglugit, phenolic resin oligomer, p
- Phenols such as trimers and 8M forms of chlorophenol formaldehyde condensates, and lithium, sodium, calcium, magnesium, aluminum, and zinc thereof.

Metal salts of tin, titanium, nickel, etc., salicylic acid, p-oxybenzoic acid, ethyl p-oxybenzoate, methyl salicylate, resorcinic acid, gallic acid, butyl gallate, methylenebissalicylic acid, β-oxynaphthoic acid, tannin acids, oxyaromatic carboxylic acids and substituted derivatives thereof such as β-oxynaphthoic acid amide, methyl β-oxynaphthoate, etc., as well as metal salts thereof as described above, phthalic acid, benzoic acid, terephthalic acid, pyromellitic acid, Trimelite ugly, toluic acid.

Carboxylic acids such as l.2-oxystearic acid, oxalic acid, lauric acid, stearic acid, tartaric acid, citric acid, anthranilic acid, etc. and metal salts thereof as mentioned above, p-toluenesulfonic acid, sulfanyl acid, metanilic acid, l-naphthalene sulfonic acid centre.

acid, 1.5 naphthalenedisulfonic acid, sulfosalicylic acid, phenolsulfonic acid.

Sulfonic acids such as naphthionic acid, diefferic acid, dodecylbenzenesulfonic acid, ligninsulfonic acid, sulfonated naphthalene, formaldehyde condensates, etc., and metal salts thereof as mentioned above, 5-chlorobenzotriazole, 5-butylbenzotriazole, dibenes. Sotriazole, 4 benzotriazole sulfonic acid, benzotriazole 5 carboxylic acid, 5 oxybensotriazole, 1
Examples include azoles such as benzyl 5-oxybenztriazole, triazole dicarboxylic acid, l-oxybenzotriazole, tetrazole, oxybenzimidazole, etc., esters and amides thereof, and metal salts thereof as described above. , these may be used alone or in combination of two or more, but in particular, in the present invention, among these, l, 2,
3 triazoles are the most effective.

Next, referring to the solvent that is a component that is allowed to coexist with both the electron-donating color-forming dye of the present invention and the corresponding acidic substance that is an electron-accepting substance, the solvent has a boiling point of 150°C at room temperature. The above-mentioned alcohols are preferable, and specifically, alcohols include saturated alcohols such as octyl alcohol, nonyl alcohol, decyl alcohol, dodecyl alcohol, tetradecyl alcohol, cetyl alcohol, octadecyl alcohol, ceryl alcohol, and myricyl alcohol. -hydric alcohols, geraniol,
Nellore.

Examples of esters include lauryl stearate, lanolin, diphenyl phthalate, glyceride laurate, propyl laurate, glyceride valmitate, etc., and examples of ammethine include unsaturated alcohols such as linalool oleyl alcohol. is, for example, benzylideneaniline, benzylidene p-toluidine, benzylidene stearylamine, benzylidene laurylamine, benzylidene butylamine, P-methoxybenzylideneaniline, P-methoxybenzylideneanisidine, p-methoxybenzylidenestearylamine, p-isopropylbenzylideneaniline, benzylidenephenylhydrazine , benzylidene ethylamine, butylidene aniline, NN dibenzylidene zidine, 1.4 bisphenylazomethine, benzylidene naphthylamine, benzylidene picolylamine, benzylidene 6-methylpyridine, benzylidene 4-aminopyridine, etc. Amides include acet 7 amide, caprylic acid amide, lauric acid amide, myristic acid amide, stearic acid amide, oxystearic acid amide, bisstearic acid amide, acetoacetylamide.

Acetanilide, paratoluenesulfoamide, benzoic acid amide, salicylic acid amide.

Examples include oxalamide, phthalamide, phthalimide, diethylurea, thiourea, diphenylurea, benzimidazole, and the like.

In addition, Table 1 of the above-mentioned reversible change used in the present invention Book a) Product name, blue-purple *b] Product name, nail green Book C) Product name, dark pink As exemplified in Table 1 above Each thermoreversible color-changing composition is produced using an interfacial polymerization method or an in-5itu polymerization method.

By forming coexisting blades into capsules using known encapsulation methods such as submerged hardening coating method, phase separation method, and interfacial precipitation method,
As mentioned above, it can exhibit excellent functions. For example, in the case of the interfacial polymerization method, the three components of an electron-donating coloring dye, an acidic substance, a solvent, and an epoxy resin are added to an aqueous polyvinyl alcohol solution under stirring, and then several By emulsifying into oil droplets of 10 liters, then quickly adding a curing agent while raising the temperature to 80-90°C, and further heating at 90-98°C for 2 hours, an average particle size of 10-40 wells was obtained. Microcapsules of a thermoreversibly color-changing composition can be obtained, and even more excellent effects can be obtained by using, for example, the method disclosed in Japanese Patent Application No. 56-131753 by the applicant of the present application.

In addition, various drugs such as surfactants may be included in the capsule used in the present invention, if necessary.

Drying regulator, antifoaming agent, resins, crosslinking agent, catalyst.

Viscosity modifiers, solvents, dyes, oil-soluble dyes, pigments.

Luminescent pigment, optical brightener, ultraviolet absorber, ultraviolet stabilizer, infrared absorber, extender pigment, blowing agent.

Water repellent, metal powder, wax, oil and fat, antioxidant, anti-reduction agent, electrolyte, reducing agent, oxidizing agent, acid.

It does not depart from the gist of the present invention even if alkalis, preservatives, chelating agents, dyeing carriers, fragrances, etc. are appropriately added.

The urethane foam of the present invention is produced by a commonly used operating method. For example, a so-called one-shot method in which a polyhydroxyl compound, water, a catalyst, a flame retardant, and a foam stabilizer are simultaneously mixed with a polyisocyanate and foamed by reaction. Alternatively, it is carried out by a prepolymer method in which a part of the polyhydroxyl compound is reacted with the entire amount of polyisocyanate in advance, and other components are mixed with the produced prepolymer and foamed. In this case, the thermoreversible color-changing composition is basically a eutectic mixture or a solvent solution of the three components, which are electron-donating color-forming pigments, acidic substances, and solvents, in order to coexist at the same time, and is further treated with capsule inclusions, etc. water or separately as a dispersion.

In this way, the novel urethane foam according to the present invention has a wide range of physical properties ranging from soft to hard, making it suitable for various uses.

Next, specific examples of the present invention will be given, but the present invention is not limited to these examples. Note that all % in the examples and comparative examples indicates weight %.

Examples 1 and 2 and Comparative Example 1 Urethane foam was manufactured using a foaming machine using the formulation shown in Table 24 below.

Table 2 $1) 2.4-72,8-isomerization = 80/20 #1
) Trade name, thermoreversible color-changing granules #2] Trade name, thermoreversible color-changing granules #3) Trade name, fluorescent pigment The physical properties of the obtained thermoreversible color-changing polyurethane foams are shown in Table 3.

Table 3 From the results shown in Table 3, it can be seen that the physical properties of polyurethane foam are not impaired to the same extent by blending the 8 reversible discoloration composition.

Next, the obtained foam was immersed in warm water at about 40° C. and the change in color was observed. The results are shown in Table 4.

Table 4 As shown in Table 4, the foam of the comparative example remained yellow and did not show any discoloration, but the foam of Example 1.2 clearly showed a reversible color change. Coupled with the results in Table 3, it can be seen that the polyurethane foam according to the present invention is unaffected by the chemical reaction during polyurethane foam production and is reversibly discolored by heat.

Examples 3 and 4 Using the formulation shown in Table 5, urethane foam was produced using a foaming machine in the same manner as in Examples 1 and 2. Table 5 1) 2.4-/2.6-isomerization = 80/20#4
) Trade name: Thermoreversible color changing granules #5) Trade name: Phthalocyanine pigment The physical properties of the obtained foam are shown in Table 6.

Table 6: Similar to Example 1.2, the color change when immersed in about 40'O hot water is as shown in Table 7, which together with Table 6 shows the effect of the polyurethane foam of the present invention. .

Table 7 Example 5.6 Using polyester polyol as the polyol, manufacturing urethane foam using a foaming machine in the same manner as Examples 1 to 4 according to the formulation shown in Table 8 From the above results, even if polyester polyol is used, It can be seen that it is possible to obtain a polyurethane foam according to the present invention whose physical properties are not impaired and which is reversibly discolored by heat.

[Effects of the Invention] As is clear from the structure of the invention described above, the polyurethane foam of the present invention has a thermoreversible discoloration effect that is unprecedented in the past, and also has the same physical properties as a urethane foam. Therefore, it has an extremely wide range of uses as described below, and has excellent industrial applicability.

Application examples (+) Toys: Bath toys, poles and toys that change color depending on the temperature, etc.

(2) Ornaments: Colors change depending on the season.

(3) Temperature sensor: Installed inside the living room, vehicle interior, etc.

(4) Cleaners...for kitchen, bath, etc.

(5) Filters: They can detect abnormalities in the temperature of the gas or liquid that passes through them.

(6) Sound absorbing material (7) Insulation material (43) Hydroponic materials: Senses water temperature.

(9) Hot carpet core material

Claims (1)

[Claims] 1. The main components polyol and polyisocyanate,
A thermoreversible color-changeable composition comprising a thermoreversible color-changeable composition consisting of three components, an electron-donating coloring pigment, an acidic substance, and a solvent, as a coloring agent, either alone or together with ordinary dyes and pigments. Polyurethane foam. 2. The thermoreversibly color-changing polyurethane according to claim 1, wherein the thermoreversibly color-changing composition comprises three components, an electron-donating coloring dye, an acidic substance, and a solvent, coexisting as microcapsule inclusions. form. 3. The thermoreversible color-changing polyurethane foam according to claim 1, wherein the acidic substance is a 1.2.3 triazole. 4. Thermoreversible discoloration according to claim 1, wherein the solvent is one or more selected from alcohols, esters, azomethines, and amides having a boiling point of 150° C. or higher at room temperature. Polyurethane foam. 5. The thermoreversibly color-changing polyurethane foam according to claim 1, wherein the thermoreversibly color-changing composition is contained in an amount of 1 to 50 parts by weight per 100 parts by weight of polyol.