Packing for lighting fixture

Abstract

To provide a packing for a lighting fixture that may effectively suppress discoloration of a polyvinyl chloride.SOLUTION: A packing 1 for a lighting fixture includes polyurethane foam 10. The polyurethane foam 10 includes a discoloration inhibitor for a polyvinyl chloride.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present disclosure relates to gaskets for lighting fixtures. [Background technology]

[0002] Patent Document 1 discloses a gasket for lighting fixtures that contains polyurethane foam. This gasket contains a diphenylamine compound and a hindered amine compound. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2023-11424 A Summary of the Invention [Problem to be solved by the invention]

[0004] Since lighting fixture packings are usually used in contact with polyvinyl chloride, there is a demand for lighting fixture packings that can effectively prevent discoloration of polyvinyl chloride. The present disclosure has an object to provide a packing for a lighting fixture that can effectively suppress discoloration of polyvinyl chloride. The present disclosure can be realized in the following form. [Means for solving the problem]

[0005] [1] A packing for a lighting fixture comprising polyurethane foam, The polyurethane foam contains a discoloration inhibitor for polyvinyl chloride, and the polyurethane foam contains a discoloration inhibitor for polyvinyl chloride. Effect of the Invention

[0006] According to the present disclosure, it is possible to provide a gasket for a lighting fixture that can effectively suppress discoloration of polyvinyl chloride. [Brief description of the drawings]

[0007] [Figure 1] FIG. 2 is a perspective view of a gasket for a lighting fixture. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0008] Here, a preferred example of the present disclosure is given. [2] The polyvinyl chloride discoloration inhibitor is Aromatic mercapto compounds, Phosphite esters, Zinc fatty acid, and The gasket for a lighting fixture according to [1], which is one or more types selected from the group consisting of hydrotalcites.

[0009] The present disclosure will be described in detail below. In this specification, when a numerical range is described using "-", the lower limit and the upper limit are included unless otherwise specified. For example, the description "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". In this specification, the upper limit and the lower limit of each numerical range can be arbitrarily combined.

[0010] 1. Lighting fixture packing 1 A lighting fixture packing 1 according to the present disclosure is shown in Fig. 1. The lighting fixture packing 1 includes a polyurethane foam 10. The polyurethane foam 10 contains a discoloration inhibitor for polyvinyl chloride (hereinafter, also simply referred to as a discoloration inhibitor).

[0011] 2. Polyurethane foam 10 The polyurethane foam 10 is obtained from a composition containing a polyol, an isocyanate, and a discoloration inhibitor. The composition may contain at least one optional component selected from an antioxidant, an ultraviolet absorber, a blowing agent, a catalyst, a foam stabilizer, a pigment, and other additives. Each component of the composition will be described below.

[0012] 3. Polyol As the polyol, polyols for polyurethane foams can be used, and suitable examples thereof include one or more of polyether polyols, polyester polyols, polyether ester polyols, and the like.

[0013] 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. The polyether polyol may contain only one type of polyether polyol, or may contain two or more types of polyether polyols in combination.

[0014] When the polyether polyol contains ethylene oxide (EO), the content of the EO unit in the polyether polyol is 15% by mass or less, preferably 12% by mass or less, and more preferably 10% by mass or less, from the viewpoint of ensuring various physical properties of the polyurethane foam. The lower limit of the content of the EO unit in the polyether polyol is not particularly limited, and may be 0% by mass, 2% by mass or more, 4% by mass or more, or 6% by mass or more.

[0015] The number average molecular weight of the polyether polyol is not particularly limited. From the viewpoint of realizing high resilience, the number average molecular weight of the polyether polyol is preferably 1000 or more, more preferably 2000 or more, and even more preferably 2500 or more. On the other hand, from the viewpoint of ensuring the strength of the polyurethane foam, the number average molecular weight of the polyether polyol is preferably 8000 or less, more preferably 6000 or less, and even more preferably 4000 or less. From these viewpoints, the number average molecular weight of the polyether polyol is preferably 1000 or more and 8000 or less, more preferably 2000 or more and 6000 or less, and even more preferably 2500 or more and 4000 or less.

[0016] The number of functional groups of the polyether polyol is not particularly limited. The number of functional groups of the polyether polyol is preferably 2-5, more preferably 2-4, and even more preferably 2 or 3. In the present disclosure, the number of functional groups means the average number of active hydrogen groups of each component contained in the polyol.

[0017] The content of polyether polyol is preferably 50 parts by mass or more, more preferably 75 parts by mass or more, and even more preferably 80 parts by mass or more, from the viewpoint of ensuring various physical properties of the polyurethane foam, assuming the total amount of polyols to be 100 parts by mass.

[0018] Examples of polyester polyols include polyester polyols obtained by polycondensation of an aliphatic carboxylic acid such as malonic acid, succinic acid, or adipic acid, or an aromatic carboxylic acid such as phthalic acid, and an aliphatic glycol such as ethylene glycol, diethylene glycol, or propylene glycol.

[0019] Examples of the polyether ester polyol include those obtained by reacting the above-mentioned polyether polyol with a polybasic acid to form a polyester, and those having both polyether and polyester segments in one molecule.

[0020] 4. Isocyanates The isocyanate is not particularly limited as long as it is a compound having two or more isocyanate groups, and those for polyurethane foams can be used. The isocyanate may be used alone or in combination of two or more. Examples of the isocyanate include aromatic, aliphatic, and alicyclic isocyanate compounds, and modified products thereof.

[0021] Examples of aromatic isocyanate compounds include toluene diisocyanate (TDI), diphenylmethane diisocyanate (MDI), crude diphenylmethane diisocyanate, naphthalene diisocyanate (NDI), p-phenylene diisocyanate (PPDI), xylene diisocyanate (XDI), tetramethyl xylene diisocyanate (TMXDI), tolidine isocyanate (TODI), etc. Examples of aliphatic isocyanate compounds include hexamethylene diisocyanate (HDI), lysine diisocyanate (LDI), lysine triisocyanate (LTI), etc. Examples of alicyclic isocyanate compounds include isophorone diisocyanate (IPDI), cyclohexyl diisocyanate (CHDI), hydrogenated XDI (H6XDI), hydrogenated MDI (H12MDI), etc. The modified isocyanate compounds include urethane modified isocyanate compounds, dimers, trimers, carbodiimide modified compounds, allophanate modified compounds, biuret modified compounds, urea modified compounds, isocyanurate modified compounds, oxazolidone modified compounds, isocyanate modified compounds, and the like.

[0022] As the isocyanate, it is preferable to use an aromatic isocyanate compound. Among aromatic isocyanate compounds, it is more preferable to use toluene diisocyanate (TDI) in consideration of foaming properties. As the toluene diisocyanate (TDI), 2,4-toluene diisocyanate (2,4-TDI), 2,6-toluene diisocyanate (2,6-TDI), or a mixture of 2,4-toluene diisocyanate (2,4-TDI) and 2,6-toluene diisocyanate (2,6-TDI) can be mentioned. The mixture of 2,4-TDI and 2,6-TDI has a mixing ratio (2,4-TDI / 2,6-TDI, mass ratio) of preferably 50 / 50-90 / 10, more preferably 65 / 35-80 / 20.

[0023] The isocyanate index (INDEX) is preferably 85 to 120. The isocyanate index is a value obtained by dividing the number of moles of isocyanate groups in an isocyanate by the total number of moles of active hydrogen groups such as hydroxyl groups in a polyol, and multiplying the result by 100, and is calculated as [NCO equivalent of isocyanate / active hydrogen equivalent x 100].

[0024] The isocyanate content is preferably 20 parts by mass or more and 60 parts by mass or less, more preferably 25 parts by mass or more and 50 parts by mass or less, and even more preferably 30 parts by mass or more and 40 parts by mass or less, relative to 100 parts by mass of the total amount of polyol.

[0025] 5.Discoloration inhibitor The discoloration inhibitor preferably contains a chlorine radical stabilizer, which is preferably at least one selected from the group consisting of aromatic mercapto compounds, phosphites, zinc fatty acids, and hydrotalcites.

[0026] The aromatic mercapto compound is preferably one having an aromatic ring such as a benzene ring or an aromatic heterocycle as a mother nucleus and one or two mercapto groups. Specific examples of the aromatic mercapto compound include 2-mercaptobenzothiazole, 2-mercaptobenzimidazole, mercaptobenzene, 2-mercaptobenzoxazole, 2-mercaptobenzothiazole methyl ether, 4-mercaptochlorobenzene, 2-mercaptonaphthalene, 2-mercapto-5-nitropyridine, mercaptopentachlorobenzene, 2-mercaptopyridine, 4-mercaptopyridine, 2-mercapto-4(3H)-quinazoline, 2-mercaptotoluene, 3-mercaptotoluene, 4-mercaptotoluene, mercapto-2,4,5-trichlorobenzene, 4-methylbenzoylmercaptan, benzoylmercaptan, 2,5-dimethylthiophenol, and salts thereof. Among these, the aromatic mercapto compound is preferably a compound having a benzothiazole ring, a benzimidazole ring, or a benzoxazole ring, and particularly preferably 2-mercaptobenzothiazole, 2-mercaptobenzimidazole, or a salt thereof.

[0027] The content of 2-mercaptobenzothiazole as a discoloration inhibitor is preferably 0.01 parts by mass or more, more preferably 0.05 parts by mass or more, and even more preferably 0.08 parts by mass or more, when the total amount of polyol is 100 parts by mass, from the viewpoint of easily suppressing discoloration of polyvinyl chloride. The content of 2-mercaptobenzothiazole is preferably 5 parts by mass or less, more preferably 2 parts by mass or less, and even more preferably 0.5 parts by mass or less, when the total amount of polyol is 100 parts by mass, from the viewpoint of not using excessively while obtaining a discoloration suppression effect. From the above viewpoint, the content of 2-mercaptobenzothiazole is preferably 0.01 parts by mass or more and 5 parts by mass or less, more preferably 0.05 parts by mass or more and 2 parts by mass or less, and even more preferably 0.08 parts by mass or more and 0.5 parts by mass or less, when the total amount of polyol is 100 parts by mass.

[0028] Examples of phosphite esters include tetra(C12-C15 alkyl) 4,4 isopropylidene diphenyl diphosphite, trilauryl phosphite, dioleyl hydrogen phosphite, triphenyl phosphite, trisnonylphenyl phosphite, tricresyl phosphite, triethyl phosphite, tris(2-ethylhexyl) phosphite, tridecyl phosphite, tris(tridecyl) phosphite, trioleyl phosphite, diphenyl mono(2-ethylhexyl) phosphite, diphenyl monodecyl phosphite, diphenyl mono(tridecyl) phosphite, trilauryl trithio phosphite, diethyl hydrogen phosphite, bis(2-ethylhexyl) hydrogen phosphite, dilauryl hydrogen phosphite, diphenyl hydrogen phosphite, tetraphenyl dipropylene glycol diphosphite, 4,4'-butylidene bis(3-methyl-6-t-butylphenyl ditridecyl phosphite), a mixture of bis(tridecyl)pentaerythritol diphosphite and bis(nonylphenyl)pentaerythritol diphosphite, bis(decyl)pentaerythritol diphosphite, bis(tridecyl)pentaerythritol diphosphite, tristearyl phosphite, distearyl pentaerythritol diphosphite, tris(2,4-di-t-butylphenyl)phosphite, SUMILIZER-GP (manufactured by Sumitomo Chemical Co., Ltd.), Adeka STAB HP10, Adeka STAB PEP-8, Adeka STAB PEP-36 / 36A (manufactured by Adeka Corporation), and the like. Among them, as the phosphite, tetra(C12 to C15 alkyl) 4,4 isopropylidenediphenyl diphosphite, trilauryl phosphite, and dioleyl hydrogen phosphite are particularly preferred.

[0029] The content of the phosphite is preferably 0.1 parts by mass or more, more preferably 0.5 parts by mass or more, and even more preferably 0.8 parts by mass or more, from the viewpoint of easily suppressing discoloration of polyvinyl chloride, when the total amount of the polyol is 100 parts by mass. The content of the phosphite is preferably 5 parts by mass or less, more preferably 3 parts by mass or less, and even more preferably 2 parts by mass or less, from the viewpoint of not using excessively while obtaining a discoloration suppression effect, when the total amount of the polyol is 100 parts by mass. From the above viewpoints, the content of the phosphite is preferably 0.1 parts by mass or more and 5 parts by mass or less, more preferably 0.5 parts by mass or more and 3 parts by mass or less, and even more preferably 0.8 parts by mass or more and 2 parts by mass or less, when the total amount of the polyol is 100 parts by mass.

[0030] Examples of fatty acid zinc include fatty acid zinc, fatty acid calcium, and complexes thereof. Specific examples of zinc fatty acids include zinc stearate, zinc undecylate, zinc laurate, zinc tridecylate, zinc dodecylate, zinc myristate, zinc palmitate, zinc pentadecylate, zinc behenate, zinc heptadecylate, zinc arachidate, zinc montanate, zinc oleate, zinc linoleate, zinc arachidonate, zinc behenate, etc. Among these, zinc stearate is particularly preferred as the zinc fatty acid. Specific examples of fatty acid calcium include long-chain fatty acid calcium such as calcium stearate, calcium undecylate, calcium laurate, calcium tridecylate, calcium dodecylate, calcium myristate, calcium palmitate, calcium pentadecylate, calcium behenate, calcium heptadecylate, calcium arachidate, calcium montanate, calcium oleate, calcium linoleate, calcium arachidonate, calcium behenate, etc. Among these, calcium stearate is particularly preferred as the fatty acid calcium.

[0031] When the total amount of the polyol is 100 parts by mass, from the viewpoint of facilitating the suppression of discoloration of polyvinyl chloride, the content of zinc fatty acid is preferably 0.1 part by mass or more, more preferably 0.5 part by mass or more, and still more preferably 0.8 part by mass or more. When the total amount of the polyol is 100 parts by mass, from the viewpoint of obtaining a discoloration suppression effect without excessive use, the content of zinc fatty acid is preferably 5 parts by mass or less, more preferably 3 parts by mass or less, and still more preferably 2 parts by mass or less. From the above viewpoints, when the total amount of the polyol is 100 parts by mass, the content of zinc fatty acid is preferably 0.1 part by mass or more and 5 parts by mass or less, more preferably 0.5 part by mass or more and 3 parts by mass or less, and still more preferably 0.8 part by mass or more and 2 parts by mass or less.

[0032] Examples of the hydrotalcite include hydrotalcite compounds represented by the formula (M 2+ ) 1-X (M 3+ ) X (OH)2(A n- ) X / n ·mH2O and calcined products thereof. In this formula, M 2+ represents divalent metal ions such as Mg 2+ , Zn 2+ , and M 3+ represents trivalent metal ions such as Al 3+ , Fe 3+ . A n- represents an n-valent anion such as CO3 2- , Cl - , SO4 2- . x, m, and n satisfy 0 < x < 0.5, 0 < n ≤ 4, and m ≥ 0, respectively. Among them, as the hydrotalcite, Mg4Al2(OH) 12 CO3·3H2O, Mg 3.5 Zn 0.5 Al2(OH) 12 CO3·3H2O is particularly preferred.

[0033] The content of hydrotalcite is preferably 0.1 parts by mass or more, more preferably 0.5 parts by mass or more, and even more preferably 0.8 parts by mass or more, from the viewpoint of easily suppressing discoloration of polyvinyl chloride, when the total amount of polyol is 100 parts by mass. The content of hydrotalcite is preferably 5 parts by mass or less, more preferably 3 parts by mass or less, and even more preferably 2 parts by mass or less, from the viewpoint of not using excessively while obtaining a discoloration suppression effect, when the total amount of polyol is 100 parts by mass. From the above viewpoints, the content of hydrotalcite is preferably 0.1 parts by mass or more and 5 parts by mass or less, more preferably 0.5 parts by mass or more and 3 parts by mass or less, and even more preferably 0.8 parts by mass or more and 2 parts by mass or less, when the total amount of polyol is 100 parts by mass.

[0034] 6. Antioxidants The antioxidant may be a hindered amine compound or an additive containing a hindered amine compound.As the additive containing a hindered amine compound, for example, the additive containing 20wt%-40wt% bis(1,2,2,6,6,-pentamethyl-4-piperidyl)=decanedioate, 5wt%-10wt% methyl=1,2,2,6,6-pentamethyl-4-piperidyl=sebacate, 15wt%-30wt% benzenepropanoic acid, 3,5-bis(1,1-dimethylethyl)-4-hydroxy-, C7-C9 side chain alkyl ester, 0.3wt%-1wt% 2-(2'-hydroxy-5'-methylphenyl)benzotriazole is preferred.

[0035] Specific examples of commercially available hindered amine compounds and additives containing hindered amine compounds include TINUVIN B75, CHIMASSORB119, CHIMASSORB2020, CHIMASSORB944, TINUVIN622, TINUVIN783, TINUVIN111, TINUVIN791, TINUVIN C353, TINUVIN494, TINUVIN492, TINUVIN123, TINUVIN144, TINUVIN152, TINUVIN292, TINUVIN5100, TINUVIN765, TINUVIN770, TINUVIN XT850, TINUVIN XT855, TINUVIN440, TINUVIN NOR371 (all manufactured by BASF), ADK STAB LA-52, ADK STAB LA-57, ADK STAB LA-62, ADK STAB LA-67, ADK STAB LA-63, ADK STAB LA-63P, ADK STAB LA-68LD, ADK STAB LA-82, ADK STAB LA-87, ADK STAB LA-501, ADK STAB LA-502XP, ADK STAB LA-503, ADK STAB LA-504, ADK STAB LA-505, ADK STAB LA-506, ADK STAB LA-507, ADK STAB LA-508, ADK STAB LA-509, ADK STAB LA-510, ADK STAB LA-511, ADK STAB LA-512, ADK STAB LA-513, ADK STAB LA-514, ADK STAB LA-515, ADK STAB LA-516, ADK STAB LA-517, ADK STAB LA-518, ADK STAB LA-519, ADK STAB LA-520, ADK STAB LA-521, ADK STAB LA-522, ADK STAB LA-523, ADK STAB LA-524, ADK STAB LA-525, ADK STAB LA-526, ADK STAB LA-527, ADK STAB LA-528, ADK STAB LA-529, ADK STAB LA-530, ADK STAB LA-531, ADK STAB LA-532, ADK STAB LA-533, ADK STAB LA-534, ADK STAB LA-535, ADK STAB LA-536, ADK STAB LA-5 DecaStab LA-77, Adeka STAB LX-335, Adekanol UC-605 (all manufactured by ADEKA Corporation), SANOL LS770, SANOL LS765, SANOL LS292, SANOL LS440, SANOL LS744, SANOL LS2626, SANOL LS944 (all manufactured by Sankyo Lifetech Co., Ltd.), HOSTAVIN N20, HOSTAVIN N24, HOSTAVIN N25, HOSTAVIN N26, HOSTAVIN N27, HOSTAVIN N28, HOSTAVIN N29, HOSTAVIN N30, HOSTAVIN N40, HOSTAVIN N50, HOSTAVIN N60, HOSTAVIN N70, HOSTAVIN N80, HOSTAVIN N90, HOSTAVIN N10, HOSTAVIN N120, HOSTAVIN N120, HOSTAVIN N120, HOSTAVIN N24, HOSTAVIN N120, HOSTAVIN N26 ...120, HOSTAVIN N26, HOSTAVIN N120, HOSTAVIN N26, HOSTAVIN N120, HOSTAVIN N120, HOSTAVIN N26 Tabin N30, Hostavin N321, Hostavin PR31, Hostavin 3050, Hostavin 3051, Hostavin 3052, Hostavin 3053, Hostavin 3055, Hostavin 3058, Hostavin 3063, Hostavin 3212, Hostavin TB01, Hostavin TB02, Nylostab S-EED (all manufactured by Clariant Japan), Tomiso BF77 (Yoshitomi Fine Chemical Co., Ltd.), CYASORB UV3346, CYASORB UV3529, CYASORB UV3853 (Sun Chemical Co., Ltd.), SUMISORB TM61 (Sumitomo Chemical Co., Ltd.), GOODRITE UV3159, GOODRITE UV3034, GOODRITE UV3150, GOODRITE 3110x128 (all BFGoodrich Co.), UVINUL 4049, UVINUL 4050, UVINUL 5050 (all manufactured by BASF). TINUVIN 144, TINUVIN 765, TINUVIN B75, ADK STAB LA-52, and LA-62 also function as ultraviolet absorbents, which will be described later. The hindered amine compounds may be used alone or in combination of two or more. Among these, TINUVIN B75 is preferred as an additive containing a hindered amine compound.

[0036] The content of TINUVIN B75 as an antioxidant is preferably 0.1 parts by mass or more, more preferably 0.5 parts by mass or more, and even more preferably 1 part by mass or more, from the viewpoint of easily suppressing discoloration of polyvinyl chloride, when the total amount of polyol is 100 parts by mass. The content of TINUVIN B75 is preferably 10 parts by mass or less, more preferably 5 parts by mass or less, and even more preferably 3 parts by mass or less, from the viewpoint of not using excessively while obtaining a discoloration suppression effect, when the total amount of polyol is 100 parts by mass. From the above viewpoints, the content of TINUVIN B75 is preferably 0.1 parts by mass or more and 10 parts by mass or less, more preferably 0.5 parts by mass or more and 5 parts by mass or less, and even more preferably 1 part by mass or more and 3 parts by mass or less, when the total amount of polyol is 100 parts by mass.

[0037] 7. UV absorbers Examples of the ultraviolet absorber include benzotriazole-based ultraviolet absorbers, triazine-based ultraviolet absorbers, benzophenone-based ultraviolet absorbers, benzoate-based light stabilizers, formamidine-based compounds, hindered amine-based light stabilizers, etc. As the ultraviolet absorber, 2-(2H-benzotriazol-2-yl)-6-dodecyl-4-methylphenol (linear and branched types) is preferred. Specific examples of commercially available ultraviolet absorbents include TINUVIN571, TINUVIN P, TINUVIN234, TINUVIN326, TINUVIN327, TINUVIN328, TINUVIN329, TINUVIN144, TINUVIN765, TINUVIN B75, etc. (all manufactured by BASF), Adeka STAB LA-52, LA-62, LA-72 (all manufactured by ADEKA), Zikasorb R, Zikasorb BS, ZIKA-FA02, ZIKA-FUA, ZIKA-FUV, ZIKA-UVS3, ZIKA-UVS4, etc. (all manufactured by ZIKO).

[0038] 8.Other additives The blowing agent is an optional component. The blowing agent may be water, a fluorocarbon substitute, or a hydrocarbon such as pentane, which may be used alone or in combination. Water is particularly preferred as the blowing agent. In the case of water, carbon dioxide gas is generated during the reaction of the polyol with the isocyanate, and the foaming is caused by the carbon dioxide gas. The amount of water as the blowing agent is preferably 1.0 parts by mass or more and 4.0 parts by mass or less, more preferably 1.5 parts by mass or more and 3.5 parts by mass or less, and even more preferably 2.0 parts by mass or more and 3.0 parts by mass or less, relative to 100 parts by mass of the polyol.

[0039] The catalyst is mainly for promoting the urethane reaction between polyols and polyisocyanates. As the catalyst, known catalysts usually used in polyurethane foams, such as tertiary amines such as 6-dimethylamino-1-hexanol, triethylenediamine, N,N-dimethylaminoethanol, and N,N',N'-trimethylaminoethylpiperazine, organometallic compounds such as stannous octoate and stannous octoate, acetates, and alkali metal alcoholates can be used. The content of 6-dimethylamino-1-hexanol as a catalyst is preferably 0.01 parts by mass or more and 5 parts by mass or less, more preferably 0.1 parts by mass or more and 1 part by mass or less, and even more preferably 0.2 parts by mass or more and 0.5 parts by mass or less, relative to 100 parts by mass of polyol. The content of stannous octoate as a catalyst is preferably 0.01 to 5 parts by mass, more preferably 0.1 to 1 part by mass, and even more preferably 0.2 to 0.5 parts by mass, per 100 parts by mass of polyol.

[0040] The foam stabilizer is not particularly limited. Examples of the foam stabilizer include silicone-based foam stabilizers and fluorine-containing compound-based foam stabilizers. Examples of the silicone-based foam stabilizer include polyether-modified silicones such as copolymers of dimethylpolysiloxane and polyether. The foam stabilizer may be used alone or in combination of two or more. The content of the foam stabilizer is preferably 0.01 parts by mass or more and 5 parts by mass or less, more preferably 0.3 parts by mass or more and 2 parts by mass or less, and even more preferably 0.5 parts by mass or more and 1 part by mass or less, relative to 100 parts by mass of the polyol.

[0041] The pigment is mixed in order to give the polyurethane foam 10 an appropriate color, and a pigment according to the desired color is used. An example of the coloring agent is a black pigment.

[0042] 9. Manufacturing method of polyurethane foam 10 The polyurethane foam 10 can be produced by a known foaming method in which the above composition is stirred and mixed to react the polyol with the polyisocyanate. The foaming method includes slab foaming and mold foaming, and either molding method may be used. Slab foaming is a method in which the mixed polyurethane resin composition is discharged onto a belt conveyer and foamed at atmospheric pressure and room temperature. On the other hand, mold foaming is a method in which the mixed polyurethane resin composition is filled into a mold (forming die) and foamed within the mold.

[0043] 10. Physical properties of polyurethane foam 10 The physical properties of the polyurethane foam 10 can be appropriately set depending on the application, etc. The polyurethane foam preferably has the following physical properties.

[0044] (1) Density (apparent density) The density of the polyurethane foam 10 (JIS K7222:2005) is preferably 15 kg / m 3 More than 60kg / m 3 More preferably, it is 25 kg / m or less. 3 More than 50kg / m 3 More preferably, it is 30 kg / m or less. 3 More than 40kg / m 3 The following is the result.

[0045] (2) 25% ILD hardness The 25% ILD hardness (JIS K6400-2:2012 D method) of the polyurethane foam 10 is preferably 10N-600N, more preferably 50N-400N, and even more preferably 100N-200N.

[0046] (3) Tensile strength The tensile strength (based on JIS K6400-5:2012) of the polyurethane foam 10 is preferably 50 kPa or more, more preferably 80 kPa or more, and even more preferably 100 kPa or more. The upper limit of the tensile strength of the polyurethane foam 10 is not particularly limited, and is, for example, 130 kPa or less.

[0047] (4) Elongation The elongation (JIS K6400-5:2012) of the polyurethane foam 10 is preferably 100% or more, more preferably 130% or more, and even more preferably 160% or more. The upper limit of the elongation of the polyurethane foam 10 is not particularly limited, and is, for example, 200% or less.

[0048] (5) Compressive residual strain The compression set of the polyurethane foam 10 when compressed by 50% (JIS K6400-4:2004 Method A) is preferably 8.0%, more preferably 4.0% or less, and even more preferably 2.0% or less. There is no particular lower limit to the compression set of the polyurethane foam 10, and it is, for example, 1.0% or more.

[0049] (6) Repeated compression set The repeated compression set of the polyurethane foam 10 (JIS K6400-4:2004 Method B) is preferably 5.0% or less, more preferably 3.5% or less, and even more preferably 1.5% or less. There is no particular lower limit to the repeated compression set of the polyurethane foam 10, and it is, for example, 0.1% or more.

[0050] (7) ΔYI value The ΔYI value before and after the discoloration test for polyurethane foam 10 is preferably 4.0 or more and 9.0 or less, more preferably 4.5 or more and 8.0 or less, and even more preferably 5.0 or more and 6.0 or less. In the discoloration test, polyurethane foam 10 placed on wallpaper is compressed by 50% with a jig, sealed with a polymer film, and left in an 80° C. atmosphere for 10 days. The size of polyurethane foam 10 is smaller than that of the wallpaper.

[0051] 11. Uses of Lighting Fixture Packing 1 The lighting fixture packing 1 is used, for example, by being adhered to the ceiling side surface of a ceiling-mounted lighting fixture. The ceiling-mounted lighting fixture is attached to the ceiling by a hook ceiling or the like. The lighting fixture packing 1 is compressed between the ceiling-mounted lighting fixture and the ceiling. The lighting fixture packing 1 comes into contact with polyvinyl chloride wallpaper on the ceiling.

[0052] 12. Effects of this embodiment The polyurethane foam 10 included in the lighting fixture packing 1 of this embodiment contains a polyvinyl chloride discoloration inhibitor. It can be assumed that the discoloration inhibitor eliminates chlorine radicals generated in polyvinyl chloride. For example, it can be assumed that the discoloration inhibitor migrates to polyvinyl chloride and eliminates chlorine radicals generated in polyvinyl chloride. Alternatively, it can be assumed that the discoloration inhibitor eliminates chlorine radicals generated in polyvinyl chloride at the contact surface of the lighting fixture packing 1 with polyvinyl chloride. Therefore, the lighting fixture packing 1 can effectively inhibit discoloration of polyvinyl chloride by eliminating chlorine radicals that yellow polyvinyl chloride.

[0053] In the past, polyurethane foam was sometimes provided with a coating to inhibit the migration of substances that promote discoloration of polyvinyl chloride. However, the lighting fixture packing 1 of the present embodiment does not require such a coating, and does not require post-processing of the polyurethane foam. In addition, in the past, a specific amine catalyst such as an N,N-dimethylaminoalkylurea compound was sometimes used in polyurethane foam to suppress discoloration of polyvinyl chloride. However, in the lighting fixture packing 1 of the present embodiment, there is no need to use such a specific amine catalyst, and a general-purpose amine catalyst can be used.

[0054] In addition, the various numerical ranges described in this specification can be arbitrarily combined with their upper and lower limits, and all such combinations are considered to be preferred numerical ranges described in this specification. EXAMPLES

[0055] The present invention will be described more specifically below with reference to examples.

[0056] 1. Preparation of Polyurethane Foam Polyurethane foams of Examples 1-15 and Comparative Examples 2-4 were prepared according to the blending ratios shown in Table 1-3. In Table 1-3, the blending ratios are expressed as blending ratios (parts by mass) when the polyol is taken as 100 parts by mass. In Comparative Example 1, an evaluation test was performed without using a polyurethane foam, as described later.

[0057] [Table 1]

[0058] [Table 2]

[0059] [Table 3]

[0060] Details of the raw materials for polyurethane foam in Table 1-3 are shown below. Polyol: Polyether polyol, Product name: GP-3050NS (manufactured by Sanyo Chemical Industries, Ltd.), OHV: 56.1, Functional group number: 3, Molecular weight: 3000 Foaming agent: Water Amine catalyst: 6-dimethylamino-1-hexanol, product name: Kao Raiser No. 25 (manufactured by Kao Corporation) Metal catalyst: Stannous octylate, product name: MRH110 (manufactured by Johoku Chemical Industry Co., Ltd.) Foam stabilizer...Product name: SZ-1136 (Dow Toray) Pigment: Black pigment Antioxidant: 20wt%-40wt% of bis(1,2,2,6,6-pentamethyl-4-piperidyl)=decanediol, 5wt%-10wt% of methyl 1,2,2,6,6-pentamethyl-4-piperidyl sebacate; 15wt%-30wt% of benzenepropanoic acid, 3,5-bis(1,1-dimethylethyl)-4-hydroxy-, C7-C9 side chain alkyl ester; A mixture of 0.3wt%-1wt% 2-(2'-hydroxy-5'-methylphenyl)benzotriazole, product name: TINUVIN B75 (manufactured by BASF) UV absorber: 2-(2H-benzotriazol-2-yl)-6-dodecyl-4-methylphenol (straight-chain and branched), product name: TINUVIN 571 (manufactured by BASF) Aromatic mercapto compounds: 2-mercaptobenzothiazole, product name: Noccela M (manufactured by Ouchi Shinko Chemical Industry Co., Ltd.) Phosphite ester 1: Tetra(C12-C15 alkyl)-4,4'-isopropylidenediphenyl diphosphite, product name: JA-805 (manufactured by Johoku Chemical Industry Co., Ltd.) Phosphite ester 2: Trilauryl phosphite, product name: JP-312L (manufactured by Johoku Chemical Industry Co., Ltd.) Phosphite ester 3: Tetraphenyldipropylene glycol diphosphite, product name: JPP-100 (manufactured by Johoku Chemical Industry Co., Ltd.) Fatty acid zinc 1: Zinc stearate aqueous dispersion, product name: ZSE-2 (manufactured by Nitto Kasei Kogyo Co., Ltd.) Fatty acid zinc 2: Complex of calcium stearate and zinc stearate, calcium to zinc molar ratio is 1:1, product name: HT-00 (manufactured by Nitto Kasei Kogyo Co., Ltd.) Hydrotalcite 1…Mg4Al2(OH) 12 CO3·3H2O, Product name: HT-1 (manufactured by Sakai Chemical Industry Co., Ltd.) Hydrotalcite 2…Mg 3.5 Zinc 0.5 Al2(OH) 12 CO3·3H2O, Product name: HT-7 (manufactured by Sakai Chemical Industry Co., Ltd.) Isocyanate: T-65 (manufactured by Mitsui Chemicals, Covestro) consisting of toluene-2,4-diisocyanate (2,4-TDI) and toluene-2,4-diisocyanate / toluene-2,6-diisocyanate (2,6-TDI) in a ratio of 65:35; A mixture of 2,4-TDI and 2,6-TDI in a ratio of 80:20 (manufactured by Mitsui Chemicals and Covestro) and T-80 In Tables 1-3, the part by mass of fatty acid zinc salt 1 in Examples 5 and 9 is "2.8", but the solid content concentration of zinc stearate is 1 part by mass.

[0061] 2. Test Method (1) Discoloration test In Examples 1-11 and Comparative Examples 2 and 3, the polyurethane foam placed on the wallpaper was compressed by 50% with a tool, sealed with a polymer film, and left in an 80°C atmosphere for 10 days. The size of the polyurethane foam was smaller than that of the wallpaper. Polyvinyl chloride (Toli "VS7001") was used for the wallpaper. The L before and after the test * , a * , b * The YI value was measured using a measuring device (product name: Color Meter SM-T (manufactured by Suga Test Instruments Co., Ltd.)). * The values ​​of ab and ΔYI were calculated. ΔE * ab is ((ΔL * ) 2 +(Δa * ) 2 +(Δb * ) 2 ) 1 / 2 It can be calculated using the formula: where ΔL * , Δa * , Δb * , ΔYI are the L before and after the test (initial and final phase), respectively. * , a * , b * , the difference between YI. In Comparative Example 1, no polyurethane foam was used, and the same discoloration test as in Examples 1-11 and Comparative Examples 2 and 3 was carried out on the wallpaper. The wallpaper used in Examples 1-11 and Comparative Examples 1-3 and the wallpaper used in Examples 12-15 and Comparative Example 4 were from different production lots.

[0062] (2) Evaluation of the physical properties of polyurethane foam (2-1) Density (apparent density) The density was measured using JIS K7222:2005.

[0063] (2-2) Rebound elasticity The impact resilience was measured using JIS K6400-3:2011.

[0064] (2-3) 25% ILD hardness The 25% ILD hardness was measured using JIS K6400-2:2012 D method.

[0065] (2-4) Tensile strength The tensile strength was measured using JIS K6400-5:2012.

[0066] (2-5) Elongation Elongation was measured using JIS K6400-5:2012.

[0067] (2-6) Compressive residual strain The compression set at 50% compression was measured using JIS K6400-4:2004 Method A.

[0068] (2-7) Repeated compression residual strain The repeated compression set was measured using JIS K6400-4:2004 Method B.

[0069] 3.Results The results are shown in Tables 1-3. As shown in Tables 1 and 2, ΔYI was 4.9-7.0 in Examples 1-11, whereas ΔYI was 5.5 in Comparative Example 1. This shows that by using a discoloration inhibitor (chlorine radical stabilizer) as in Examples 1-11, the yellowing of polyvinyl chloride (wallpaper) can be suppressed to the same extent as when no polyurethane foam is used (Comparative Example 1).

[0070] As shown in Tables 1 and 2, ΔYI was 4.9-7.0 in Examples 1-11, while ΔYI was 7.2 and 8.2 in Comparative Examples 2 and 3. This shows that by using a discoloration inhibitor (chlorine radical stabilizer) as in Examples 1-11, the yellowing of polyvinyl chloride (wallpaper) can be suppressed more than when no discoloration inhibitor is used (Comparative Examples 2 and 3). Furthermore, it was found that when any of the aromatic mercapto compounds (Example 1), phosphites (Examples 2-4), zinc fatty acids (Examples 5, 8-11), and hydrotalcites (Examples 6 and 7) was used as the discoloration inhibitor, the yellowing of polyvinyl chloride (wallpaper) could be suppressed more than when no discoloration inhibitor was used (Comparative Examples 2 and 3).

[0071] As shown in Table 3, ΔYI was 4.9-8.2 in Examples 12-15, whereas ΔYI was 9.0 in Comparative Example 4. This shows that by using 0.1-1 part by mass of 2-mercaptobenzothiazole as a discoloration inhibitor (chlorine radical stabilizer) as in Examples 12-15, the yellowing of polyvinyl chloride (wallpaper) can be suppressed more than when no discoloration inhibitor is used (Comparative Example 4).

[0072] 4. Effects of the embodiment According to the above examples, discoloration of polyvinyl chloride in contact with the polyurethane foam can be suppressed by the polyurethane foam containing a discoloration inhibitor (chlorine radical stabilizer).

[0073] The present disclosure is not limited to the above-described embodiments, and various modifications and variations are possible. [Explanation of symbols]

[0074] 1. Lighting fixture packing 10…Polyurethane foam

Claims

1. A packing for a lighting fixture comprising polyurethane foam, The polyurethane foam contains a discoloration inhibitor for polyvinyl chloride, and the polyurethane foam contains a discoloration inhibitor for polyvinyl chloride.

2. The polyvinyl chloride discoloration inhibitor is Aromatic mercapto compounds, Phosphite esters, Zinc fatty acid, and The gasket for a lighting fixture according to claim 1 , which is one or more selected from the group consisting of hydrotalcites.

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