JP2003321529A - Method for producing automobile interior material - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for producing a lightweight automobile interior material without causing yellowing with time. <P>SOLUTION: In the method for producing an automobile interior material obtained by laminating and bonding a surface layer material to a porous base material through an organic polyisocyanate, the organic polyisocyanate is an yellowing-free polydiisocyanate. The organic polyisocyanate is preferably selected from an urethodione-modified-, an isocyanulate modified-, an allophanate modified- and a biuret modified-polyisocyanate which is derived from an yellowing-free organic diisocyanates. <P>COPYRIGHT: (C)2004,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a method for manufacturing an automobile interior material. More specifically, it relates to a method for producing an automobile interior material using a specific polyisocyanate.

[0002]

2. Description of the Related Art As one of the methods for manufacturing automobile interior materials,
A method is known in which a porous base material and a surface layer material are laminated with an adhesive, and the obtained interior material is used as a door trim, a ceiling material, or the like. As a specific production method, for example, in JP-A-58-5346, a flexible urethane foam or a rigid urethane foam is impregnated with isocyanate, water and a urethanization catalyst are added thereto, and both surfaces are reinforced with a glass mat. Molded articles have been proposed. Further, Japanese Patent Application Laid-Open No. 4-211416 proposes a molded product obtained by sandwiching an open-celled room temperature moldable polyurethane foam between two glass mats to which an adhesive is applied and thermoforming the same.

[0003]

For these adhesives, aromatic polyisocyanates are often used in terms of strength and curability. However, the aromatic polyisocyanate has a drawback that it yellows over time.

[0004]

Means for Solving the Problems The inventors of the present invention have conducted extensive studies and studies to improve such conventional problems, and as a result, the strength and curability are almost the same, and the appearance is excellent. The present invention has been completed by finding that the above problems can be improved by using a yellowing isocyanate.

That is, the present invention provides a method for producing an automobile interior material obtained by laminating and adhering a porous base material and a surface layer material via an organic polyisocyanate, wherein the organic polyisocyanate is a non-yellowing polyisocyanate. A method for producing a characteristic automobile interior material.

Further, the present invention provides the method for producing an automobile interior material, wherein the organic polyisocyanate is a uretdione modified product, an isocyanurate modified product, or an allophanate modified product derived from a non-yellowing organic diisocyanate.
A method for producing an automobile interior material, which is selected from a modified biuret.

[0007]

BEST MODE FOR CARRYING OUT THE INVENTION The organic polyisocyanate used in the present invention is a non-yellowing polyisocyanate. The non-yellowing polyisocyanate may be a water-emulsifiable type. In the present invention, “non-yellowing polyisocyanate” is a general term for polyisocyanates that do not have a resonance structure such as a benzene ring or a naphthalene ring in the molecular skeleton.

The viscosity of the organic polyisocyanate is preferably 3,000 mPa · s or less at 25 ° C., and particularly preferably 1,500 mPa · s or less at 25 ° C. in consideration of coating properties and the like.
Further, the isocyanate content is preferably 10 to 25% by mass, and particularly preferably 12 to 22% by mass.

The non-yellowing polyisocyanate is preferably selected from uretdione modified products, isocyanurate modified products, allophanate modified products, and biuret modified products derived from non-yellowing organic diisocyanates. Considering the durability, durability, etc., polyisocyanates selected from isocyanurate modified products, allophanate modified products, and biuret modified products derived from non-yellowing organic diisocyanates are particularly preferable.

The term "non-yellowing organic diisocyanate" is a general term for aliphatic diisocyanates and alicyclic diisocyanates. Here, as the aliphatic diisocyanate, tetramethylene diisocyanate, hexamethylene diisocyanate (hereinafter abbreviated as HDI), decamethylene diisocyanate, lysine diisocyanate, triethylene glycol diisocyanate,
Examples include trimethylhexamethylene diisocyanate. Examples of the alicyclic diisocyanate include isophorone diisocyanate, cyclohexyl diisocyanate, dicyclohexylmethane diisocyanate, hydrogenated tolylene diisocyanate, hydrogenated xylylene diisocyanate, and tetramethyl hydrogenated xylylene diisocyanate. In the present invention, HDI is preferable in consideration of the viscosity of the modified polyisocyanate to be obtained.

That is, in the present invention, a polyisocyanate selected from isocyanurate-modified polyisocyanate of HDI, allophanate-modified polyisocyanate of HDI, and biuret-modified polyisocyanate of HDI is most preferable, and the production method thereof is not particularly limited, and is known. It is obtained by the manufacturing method of.

The HDI isocyanurate-modified polyisocyanate is produced by urethane-modifying HDI itself or a part of HDI with a polyol (a diol having a molecular weight of 500 or less is preferable) and then reacting with an isocyanurate-forming catalyst. Examples of the method include a method of carrying out a chemical reaction and stopping the isocyanurate-forming reaction by adding a catalyst poison when a predetermined reaction rate is reached.

The HDI allophanate-modified polyisocyanate is produced by urethane-modifying a part of HDI with a polyol (preferably mono and / or diol having a molecular weight of 500 or less) and then carrying out the allophanate-forming reaction in the presence of an allophanate-forming catalyst. A method of deactivating the catalyst by adding a catalyst poison at a predetermined reaction rate or when the urethane group disappears.

The method for producing a biuret-modified polyisocyanate of HDI is as follows. After modifying a part of HDI with polyamine or water (preferably water), a biuretization reaction is carried out in the presence of a biuretization catalyst to obtain a predetermined reaction rate. A method in which a catalyst poison is added to stop the biuretization reaction when the temperature reaches the level can be mentioned.

In any case, after the reaction is stopped, unreacted HDI is removed by thin-film distillation or the like to obtain an unreacted HDI content of 1%.
%, It is preferable to remove it until the content becomes less than or equal to%, since there is almost no irritating odor during the production of the interior material.

The organic polyisocyanate used in the present invention may include an antioxidant, an ultraviolet absorber, and
Various known additives and auxiliaries such as flame retardants, plasticizers, pigments / dyes, antibacterial agents / antifungal agents can be added.

The "surface layer material" in the present invention is a general term for members used as the outermost parts of interior materials such as skin materials and back materials. Examples of the surface layer material include polyester-based, polyolefin-based, polyvinyl chloride-based, polyamide-based sheets, non-woven fabrics, tricots, and the like.

The porous base material used in the present invention is used as a core material for an interior material, and may be any as long as it has moldability by coating or impregnating with an isocyanate and thermoforming, for example. , Cloth, paper, felt, wool, resin fiber, hard foamed plastic, soft foamed plastic, and ribbon dead foam obtained by solidifying foam chips. A particularly preferred porous substrate in the present invention is urethane foam. Further, in order to impart strength to the interior material, it is preferable to use a reinforcing material such as glass fiber between the surface layer material and the porous substrate.

Specific methods for producing the automobile interior material of the present invention include the following methods. 1) The above-mentioned organic polyisocyanate is impregnated or coated on one side or both sides of the porous base material and / or the surface layer material, and then water and / or a catalyst is sprayed on the isocyanate coated surface to be laminated. 2) The above-mentioned organic polyisocyanate, or the organic polyisocyanate and the catalyst are emulsified and dispersed in water, and the dispersion is impregnated or coated on one side or both sides of the porous base material and / or the surface layer material to be laminated. 3) After spraying water and / or a catalyst on one or both sides of the porous base material and / or surface layer material, one or both surfaces of the porous base material and / or surface layer material are impregnated with the above-mentioned organic polyisocyanate or Apply and stack. 4) The above-mentioned organic polyisocyanate is impregnated or coated on one surface of the porous substrate and / or the surface layer material, water and / or a catalyst is sprayed on the other surface, and then laminated. In addition, it is preferable to perform thermoforming after or simultaneously with the lamination.

An active hydrogen group-containing compound other than water may be used together for the purpose of improving the adhesive strength. As the active hydrogen group-containing compound, ethylene glycol,
1,2-propanediol, 1,3-propanediol, 1,2-butanediol, 1,3-butanediol, 1,4-butanediol, neopentyl glycol, diethylene glycol, dipropylene glycol,
Examples thereof include low molecular weight polyols and low molecular weight polyamines such as trimethylolpropane, glycerin, ethylenediamine, hexamethylenediamine, diaminodiphenylmethane, isophoronediamine and diethylenetriamine. When an active hydrogen group-containing compound other than water is used, the amount used is preferably 2 to 10% by mass of polyisocyanate.

Examples of the catalyst include triethylamine, tripropylamine, tributylamine, N-methylmorpholine, dimethylbenzylamine, N, N,
N ', N'-tetramethylhexamethylenediamine,
N, N, N ', N', N "-pentamethyldiethylenetriamine, bis- (2-dimethylaminoethyl) ether, triethylenediamine, 1,8-diazabicyclo (5,4,0) undecene-7,1 , Tertiary amines such as 2-dimethylimidazole and 1-butyl-2-methylimidazole, or organic acid salts thereof, organometallic compounds such as stannas octoate, dibutyltin dilaurate, and zinc naphthenate. , 2, 4, 6,-
Tris (dimethylaminomethyl) phenol, N,
N ′, N ″ -tris (dimethylaminopropyl) hexahydro-triazine, a mixture of potassium octylate and diethylene glycol, a mixture of tertiary amine, potassium octylate and diethylene glycol, potassium phenolate, phenolate such as sodium methoxide, alcoholate, More particularly effective 2,4,6-tris (dimethylaminomethyl) phenol, 2,4-bis (dimemylaminomethyl) phenol, 2,6-di-t-butyl-4-
Examples include isocyanurate forming catalysts such as dimethylaminotrimethylsilanephenol, triethylaminediazabicycloundecene, lead naphthenate, and lead octenoate.
When the catalyst is used alone, the amount of the catalyst used is preferably 2 to 20 mass% with respect to the organic polyisocyanate. When water and a catalyst are used in combination, the used mass ratio of water / catalyst is 1/1 to 15
/ 1 is preferable. In this case, the amount of the catalyst / water mixture used is preferably 2 to 80% by mass based on the organic polyisocyanate.

The conditions for thermoforming are: mold temperature: 85
~ 150 ° C, time: preferably 10 to 150 seconds,
Mold temperature: 90 to 140 ° C., time: 20 to 120 seconds are preferable. The pressure is 0.1 to 10 MPa, especially 0.2
-5 MPa is preferable.

The mold temperature below 85 ° C. (eg 80
Immediately after thermoforming at (.degree. C.), it is often not sufficiently adhered, but it is possible to increase the strength by further aging at 30 to 70.degree. C. for 0.5 to 48 hours. However, thermoforming at a low temperature is not preferable because it requires such an aging step and is inferior in productivity.

The total apparent density per unit volume of the automobile interior material thus obtained is 100 to 150 kg /
m ³ is preferred. The total apparent density per unit area is 0.
5 to 1 kg / m ² is preferable. The thickness of the interior material is 3
-7 mm is preferable.

[0025]

Industrial Applicability According to the present invention, an automobile interior material which is free from discoloration for a long period of time can be obtained. The automobile interior material obtained by the present invention is lightweight and excellent in productivity, and is suitable for a molded ceiling. The present invention can also be applied to fields such as interior materials for ships and building materials (composite panels).

[0026]

EXAMPLES The present invention will be described below with reference to examples and comparative examples, but the present invention is not limited thereto. "%" In the examples is "mass%" unless otherwise specified.

[Synthesis of allophanate-modified polyisocyanate] In a reactor having a stirrer, a thermometer, a cooler and a nitrogen gas introducing tube: a volume of 1 L, 950 g of hexamethylene diisocyanate (HDI) and 5 parts of isopropanol were added.
0 g was charged and the urethanization reaction was performed at 90 ° C. for 2 hours.
When the reaction product was analyzed by FT-IR, the hydroxyl group had disappeared. Next, 0.2 g of zirconium 2-ethylhexanoate was charged and reacted at 90 ° C. for 3 hours. When the reaction product was analyzed by FT-IR and ¹³ C-NMR, the urethane group had disappeared. Phosphoric acid is then added to 0.
A termination reaction was performed at 50 ° C. for 1 hour after charging 1 g. The isocyanate content of the reaction product after the termination reaction was 40.5%. The reaction product was subjected to thin film distillation at 130 ° C. and 0.04 kPa to obtain an isocyanate content of 19.4%, 2
Polyisocyanate A having a viscosity at 5 ° C of 100 mPa · s, an unreacted HDI content of 0.2% and an average number of functional groups of 2
Got Polyisocyanate A is FT-IR, ¹³ C-N
When analyzed by MR, the presence of urethane groups was not recognized, and the presence of allophanate groups was confirmed. Also,
Only trace amounts of uretdione groups and isocyanurate groups were observed.

[Manufacture of Interior Material] Examples 1 to 7 and Comparative Example 1 Thermoformable rigid urethane foam (density = 35 kg /
m ³ , length = 200 mm, width = 100 mm, thickness = 5 m
m) was coated with 6 g of the isocyanate shown in Table 1 on one side, and the catalyst and water (water: triethylenediamine = 93: 7,
(Mass ratio) 3 g of a mixed solution is sprayed, glass mat and polyester non-woven fabric are sequentially laminated on the upper and lower surfaces, and molded with a mold heated to 120 ° C. at 2.8 MPa for 120 seconds to obtain a thickness of 6 mm.
A molded product of was obtained. The composition of the interior material is non-woven fabric / glass mat / hard urethane foam / glass mat / non-woven fabric. The obtained molded product was extremely lightweight as shown in Table 1.

Example 8, Comparative Example 2 Thermoformable rigid urethane foam (density = 35 kg /
m ³ , length = 200 mm, width = 100 mm, thickness = 5 m
m) was coated with 6 g of the isocyanate shown in Table 1 on one side, 1 g of the catalyst (triethylamine) was sprayed, and a glass mat and a polyester non-woven fabric were sequentially laminated on the upper and lower surfaces.
Molding was performed at 2.8 MPa for 120 seconds with a mold heated to 0 ° C. to obtain a molded product having a thickness of 6 mm. The composition of the interior material is non-woven fabric / glass mat / hard urethane foam / glass mat / non-woven fabric. The obtained molded product was extremely lightweight as shown in Table 1.

[0030]

[Table 1]

In Examples 1 to 8, Comparative Examples 1 and 2, and Table 1, polyisocyanates used in addition to polyisocyanate A are shown below. Coronate 2365: HDI uretdione modified polyisocyanate Nippon Polyurethane Industry Co., Ltd. product Isocyanate content = 22.3% Viscosity at 25 ° C. = 90 mPa · s Free HDI content = 0.9% Coronate HXLV: HDI isocyanurate modified polyisocyanate Product of Nippon Polyurethane Industry Co., Ltd. Isocyanate content = 23.2% Viscosity at 25 ° C. = 1,200 mPa · s Free HDI content = 0.2% Coronate HX: HDI isocyanurate-modified polyisocyanate Product of Nippon Polyurethane Industry Co., Ltd. Isocyanate content = 21.3% Viscosity at 25 ° C. = 2,500 mPa · s Free HDI content = 0.5% Duranate 24A-100: HDI biuret-modified polyisocyanate Asahi Kasei Kogyo Co., Ltd. Isocyanate content = 2 3.6% Viscosity at 25 ° C = 2,000 mPa · s Free HDI content = 0.3% Coronate 1130: Polymeric MDI Nippon Polyurethane Industry Co., Ltd. product Isocyanate content = 31.3% Viscosity at 25 ° C = 120 mPa · s * "Coronate" is a registered trademark of Nippon Polyurethane Industry Co., Ltd. * “Duranate” is a registered trademark of Asahi Kasei Corporation. * MDI: diphenylmethane diisocyanate * Coronate 1130 is a low viscosity polyisocyanate obtained by reacting polyamine obtained by the condensation reaction of aniline and formaldehyde with phosgene.

Evaluation Method <Adhesive Appearance> Immediately after demolding, the floats (non-bonded portions) on the surface layer materials were compared. ○: There is no floating of the surface material. Δ: The floating area of the surface layer material is 10% or less of the total area. X: The floating area of the surface layer material exceeds 10% of the total area. <Initial Hardness> The surface hardness (C hardness) immediately after demolding was measured. ⊚: 60 or more ∘; 50 to 60 Δ; 40 to 50 ×; 40 or less <Weather resistance> From the day after molding, the mixture was left for one month indoors in a slightly sunlit place, and the degree of yellowing was compared. ○: No change. Δ: Yellowed slightly. X: Clearly yellowing.

As shown in Table 1, the interior material obtained by the present invention was lightweight and showed good adhesiveness and weather resistance.

   ─────────────────────────────────────────────────── ─── Continued front page    F-term (reference) 3D023 BA01 BB01 BE05                 4J034 AA01 AA06 BA02 CA01 CE01                       HA01 HA07 HB05 HB08 HC03                       HC08 HC17 HC18 HC46 HC64                       HC67 HC71 HC73 QC03 RA12

Claims (2)

[Claims] 1. A method for producing an automobile interior material obtained by laminating and adhering a porous substrate and a surface layer material via an organic polyisocyanate, wherein the organic polyisocyanate is a non-yellowing polyisocyanate. Manufacturing method of automobile interior materials. 2. The method for producing an automobile interior material according to claim 1, wherein the organic polyisocyanate is a uretdione modified product, an isocyanurate modified product, or an allophanate modified product derived from a non-yellowing organic diisocyanate.
A method for producing an automobile interior material, which is selected from a modified biuret.