JPS5883019A - Polyurethane resin composition - Google Patents

Abstract

PURPOSE:The titled composition capable of providing moldings having excellent yellowing resistance and a balance between mechanical strength and flexibility which is equivalent to that of conventional products, prepared by mixing a specified, terminal isocyanato group-containing urethane prepolymer with an aliphatic diol. CONSTITUTION:A polyurethane resin composition prepared by mixing a 2-20C aliphatic diol with a terminal isocyanato group-containing urethane prepolymer prepared by reacting a polyol (e.g., polyethylene glycol) with a terminal isocyanato group-containing adduct prepared by reacting a large excess of an aliphatic and/or alicyclic diisocyanate (e.g., 1,4-tetramethylene diisocyanate, isophorone diisocyanate) with a 2-20C aliphatic diol (e.g., 1,4-butanediol) and removing excess diisocyanate, at an NCO/OH equivalent ratio R which satisfies the relationship of 2<R<=50 so that the mixing ratio expressed by an NCO/OH equivalent ratio can fall within the range of 0.8-1.5. It is possible to obtain moldings having excellent yellowing resistance and a good balance between mechanical strength and flexibility.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a polyurethane resin composition that provides a polyurethane molded product with excellent yellowing resistance and a good balance between mechanical strength and flexibility, and more specifically, various foamed molded products,
The present invention relates to an aliphatic polyurethane resin composition that is extremely useful as a molding material for elastic fibers, cast products, films, sheets, and other elastomer molded products.

For example, polyurethane resin compositions are often used as molding materials for foam molded products and other elastomer molded products used for automobile interior parts such as instrument panel handles, steering wheel centers, armrests, and headrests. However, as the incyanate component, tolylene diisocyanate (TD), diphenylmethane diincyanate (MDI), and modified products thereof, such as crude MDI and polymeric MDI (hereinafter referred to as
Aromatic polyisocyanates such as MDI (including these modified products) accounted for the majority.

Polyurethane resin compositions using these aromatic polyisocyanates generally give molded products with an excellent balance of mechanical strength and flexibility, but they have the drawback of extremely rapid yellowing when exposed to sunlight. . For this reason,
Conventionally, a polyurethane resin composition using the above-mentioned aromatic polyisocyanate is combined with an ultraviolet absorber, or the surface of a molded product obtained from the above-mentioned composition is given a yellowing resistance that satisfies the yellowing resistance over a long period of time. No denaturation can be obtained, and this is not an essential solution. In addition, methods such as coating the surface of the molded product with non-yellowing paints, skin materials, etc. may have problems with adhesion to the molded product being coated, or if the shape of the molded product is complex. There may be problems with workability, etc.
It is also extremely disadvantageous in that the number of work steps increases.

The present inventors have investigated various methods for suppressing the yellowing phenomenon of polyurethane resin compositions using aromatic polyisocyanates. This is a peculiar phenomenon when using , and it is virtually impossible to eliminate this phenomenon.

On the other hand, yellowing of polyurethane resins can be overcome by using non-yellowing type aliphatic isocyanates. With the method of replacing yellowing isocyanates, it is difficult to obtain molded products with the same balance of mechanical strength and flexibility as conventional products, and attempts to improve physical properties by changing the compounding composition are structurally difficult. It has not been possible to obtain a molded article with a balance between mechanical strength and flexibility using non-yellowing type incyanates with different hardness and reactivity.

In particular, when using hexamethylene diisocyanate, it is extremely difficult to obtain polyurethane resin moldings that have a balance between mechanical strength and flexibility, and moldings that have physical properties equivalent to polyurethane resins that use aromatic isocyanate H-. It was not possible to obtain such a polyurethane - it is not yet known. The production of practical polyurethane resins using aliphatic incyanates is a major research topic.

The present inventors have worked diligently to overcome the technical problems described above and to obtain a polyurethane resin molded product that has excellent yellowing resistance and has the same balance of mechanical strength and flexibility as conventional products. As a result of repeated research, we have completed the present invention.

That is, the present invention is directed to reacting a large excess of aliphatic and/or alicyclic diisocyanate with an aliphatic diol having 2 to 20 carbon atoms, and also producing an adduct containing a terminal incyanate group and a polyol from which the excess incyanate is removed. and the weight ratio R (NeoloH) of incyanate groups and hydroxyl groups is 2.
Terminal isocyanate group-containing urethane prepolymer obtained by reacting so as to satisfy <R≦50 and carbon number 2 to
20 aliphatic diol and the N O010H equivalent ratio is 0.
A polyurethane resin composition is provided in which the polyurethane resin composition is mixed at a ratio of 8 to 1.5.

Examples of the aliphatic diisocyanate and alicyclic diisocyanate used in the production of the urethane prepolymer that is a constituent component of the composition of the present invention include 1,4-tetramethylene diisocyanate, 1,5-pentamethylene diisocyanate, and 1,6- Examples include aliphatic diisocyanates such as hexamethylene diisocyanate, trimethylhexamethylene diisocyanate, and lysine diincyanate, and alicyclic diisocyanates such as isophorone diisocyanate and cyclohexane-1,4-diincyanate, which may be used alone or in combination. The above may be used in combination.

In addition, the number of carbon atoms to be reacted with the diisocyanate is 2 to 2.
Examples of the aliphatic diol having 0 include ethylene glycol, propylene glycol, 1.4-butanediol, 1.3-butanediol, 1.5-bentanediol, diethylene glycol, neopentyl glycol,
Examples include polyethylene glycol and polypropylene glycol, and those having a methyl group in the side chain are particularly preferred. These can be used alone or in combination of two or more.

The aliphatic and/or alicyclic diisocyanate needs to be in large excess with respect to the diol with which it is reacted, and a large excess is sufficient to form an adduct having an isocyanate group at the end. It means an excessive amount. This adduct can be easily produced by reacting a large excess of aliphatic diincyanate with a diol, usually under heating. Since this reaction product contains a large amount of unreacted diisocyanate, this can be substantially completely removed using known methods, such as distillation, to isolate the adduct containing terminal incyanate groups. I can do it. Such adducts are generally commercially available and can be easily obtained.

The urethane prepolymer used in the composition of the present invention is a urethane prepolymer having an incyanate group at the end obtained by reacting the above adduct with a polyol.

Examples of the polyol used in the above reaction include polyethylene glycol, polypropylene glycol, polyoxytetramethylene glycol, adipate type polyethylene adipate, poly(1°4-butylene adipate), poly(1,6-hexabonate), etc. These can be used alone or in combination of two or more types.Also preferred are polypropylene glycol and polypropylene glycol with ethylene oxide added to the terminal hydroxyl group.The above polyol has an average functional number of about 1. The weight average molecular weight of the polyol can be advantageously used in the range of 200 to 8,000, and the particularly preferable molecular weight is 3.5 to 3.5.
00 to 5000.

The above-mentioned adduct and the above-mentioned polyol are reacted in such a proportion that the equivalent ratio R (NooloH) of the free incyanate groups present in the former to the free hydroxyl groups present in the latter satisfies the formula 2<R≦50. When R is 2 or less, the viscosity of the reactant increases rapidly during the reaction, which is not preferable.

On the other hand, if R exceeds 50, the resulting molded product will lack mechanical strength, which is not preferred. A particularly preferred range is 5≦R≦40.

This reaction can be easily carried out according to reaction conditions commonly used in polyurethane production.

The composition of the present invention comprises the terminal isocyanate group-containing urethane prepolymer prepared as described above and the
20 aliphatic diols in which the N0010H equivalent ratio of incyanate groups and hydroxyl groups present in each is 0.
They are mixed at a ratio within the range of 8 to 1.5. Ne for OH.

If the equivalent ratio is less than 0.8, the mechanical strength of the molded product will be insufficient and the weather resistance will be significantly reduced, which is not preferable. Moreover, if it exceeds 1.5, demoldability during molding will be poor, the molded product will become brittle, and it will also become sticky, which is not preferable. A particularly preferred equivalent ratio is in the range of 0.9 to 1.1.

The aliphatic diol having 2 to 20 carbon atoms to be mixed with the urethane prepolymer containing terminal isocyanate groups is usually the same diol-i used for forming the adduct.
Different diols can also be used.

The composition of the present invention has excellent mechanical properties that could not be obtained with conventional polyurethane resins using aliphatic isocyanates, and is an extremely practical molding material that has a good balance between these properties and flexibility. Therefore, it is possible to provide an improved polyurethane molded product that does not turn yellow.

In the composition of the present invention, the types and amounts of the urethane prepolymer and aliphatic diol are selected depending on the intended use and desired physical properties. Depending on the selected combination, there are various compositions, such as those that have sufficient fluidity at room temperature, those that can obtain fluidity under mild heating conditions, or those that can obtain sufficient fluidity at room temperature when mixed with an organic solvent. However, these compositions can be easily molded by utilizing their fluidity. For example, paint 1. It is generally used as a coating material, adhesive, etc. by dissolving it in an organic solvent, but it can also be applied as is or after heating, taking advantage of its fluidity.

Furthermore, since organic solvents cannot be substantially used in the molding of foam molded products, botting materials, and other cast products, compositions that can obtain sufficient fluidity at room temperature or under heated conditions are used. As described above, the composition of the present invention can be used in a solvent-free or solvent-based manner depending on the purpose and use.

In addition, the composition of the present invention may optionally contain commonly used additives, such as a curing accelerating catalyst such as dibutyltin dilaurate, a crosslinking agent, a blowing agent, an antifoaming agent, a leveling agent, a matting agent, and an antifoaming agent. Fungicides, various fillers (for example, inorganic fibers such as glass fibers, carbon fibers, and metal fibers, organic fibers such as natural fibers, recycled fibers, and synthetic fibers, pigments, local fillers, etc.), dyes, and If necessary, ultraviolet absorbers, heat stabilizers, etc. may be added.

The polyurethane resin composition of the present invention is extremely useful as a material for molded products such as films, sheets, foams, and cast products, and is also used in paints, coating materials (e.g., glass coating materials, fiber treatment materials, leather treatment materials). etc.), and is also effective for applications such as adhesives.The present invention will be explained in more detail with reference to Examples below. Note that "part" and "chi" shown below represent parts by weight and percent by weight, respectively.

Reference example (manufacture of urethane prepolymer) Prepolymer I: Po1y-G-420P'' 89.1 parts Poly! Socyane) A'X2) 910.9 parts Dibutyltin dilaure) 0.1 part 1000
．． 1 part *1) Polypropylene glycol with an average functional number (hereinafter abbreviated as 〒) of 2 and a weight average molecular weight (hereinafter abbreviated as 7W) of 400; manufactured by Asahi Glass Co., Ltd. 1i12) 1.6-hexamethylene diisocyanate and 1.4-butanediol Adduct containing terminal isocyanate group obtained by reaction with (solid content = 100%, NC
o content = 19.7%, viscosity = 500 cp/25
C) Among the above compositions, the entire amount of polyinsyanate A was placed in a 2-t four-piece separable flask equipped with a stirrer, a cooler, and a thermometer, and heated to 50° C. under a nitrogen stream. The remaining dibutyltin dilaurate and Po
The entire amount of 1y-G-420F was added dropwise over 1 hour. After the dropwise addition was completed, heating was further continued at the same temperature for about 1 hour. After the reaction was completed, the mixture was cooled to room temperature to obtain a solvent-free urethane prepolymer I having an NCO content of 16.0% and a viscosity of 2750 cp/25°C. In this case, the N cfo10H equivalent ratio is 10.

Prepolymer ■: Poly-G-1020Pl'113) 191.7 parts Polyisocyanate A 808.3 parts 1000
．． Part 1 *3)? = 2, polypropylene glycol with MW = 1000; manufactured by Asahi Glass Co., Ltd. Using the above composition, 1, NCo content 14.3%, viscosity 3260 cp/2 in the same manner as the prepolymer ①.
Prepolymer In was obtained at 5°C. In addition, in this case, N O
The Olo H equivalence ratio is 10.

Prepolymer ■: Polypropylene glycol with f = 2, Mw = 3000; manufactured by Asahi Glass Co., Ltd. Using the above composition, prepolymer Using the same method as for polymer ①, N00 content 10.2%, viscosity 4950 cp/25
℃ prepolymer ■ was obtained. In addition, N C! in this case!
The 010H equivalent ratio is 10.

Prepolymer ■: Po1y-G-4020F” 484.5 parts Polyisocyanate) A 515.5 parts 1ooo
, part i *5) Polypropylene glycol of 〒=2, Mw=4000; manufactured by Asahi Glass Co., Ltd.

Using the above composition, the NCO content was 9.2% and the viscosity was 5550 cps/
A prepolymer (■) at 25°C was obtained. Note that N in this case
The OOlo H equivalent ratio is 10.

Prepolymer ■: Pony-G -3020F 276.1 parts Polyisocyanate A 723.9 parts 100
Using 0.1 part of the above composition, NCo content 13.6% and viscosity 2200 cps/
A prepolymer (■) at 25°C was obtained. Note that N in this case
The OOlo H equivalence ratio is 20.

Prepolymer ■: Poly-G-3020F 202.7 parts Polyincyanate A 797.3 parts 1000
．． Using 1 part of the above composition, NCo content 15.2% and viscosity 1300 cps/
Prepolymer ■ was obtained at 25°C.In addition, in this case, N
The OOlo H equivalent ratio is 30.

Prepolymer ■: Poly-G-3020P 160.2 parts Polyisocyanate A 839.8 parts 1000
, using 1 part of the above composition and in the same manner as Prepolymer I.
Co content 16.1%, viscosity 1,000 cps/25
℃ prepolymer ■ was obtained. In addition, NC01 in this case
0H equivalent) ratio is 40.

Prepolymer ■: Po1y-0420F 67.5 parts Po1
y-0240"" 67.5 parts Polyincyane iodine A 865.0 parts 1000.1 parts *6) Polyether poly quaternary resin with f = 3, Mw = 3000; manufactured by Asahi Glass Co., Ltd. The above composition After pre-blending two types of polyether polyols, the NCo content was 15.3 cm and the viscosity was 12
A prepolymer (■) of 60 cps/25°C was obtained. In addition,
In this case, the N COlo H equivalent ratio is 1°.

Prepolymer ■: Po1y-33020F 182.2 parts Po
1y-G 240 182.2 parts Polyisocyanate A 635.6 parts 1ooo, i part Using the above composition, NCo content 11.3%, viscosity 4520 cps/
At 25°C, Nofre Polymer ■ was obtained. In addition, NC in this case
! The Olo H equivalence ratio is 10.

Prepolymer X: G-300" 42.9 parts Po1y-
G 240 42.9 parts Polyisocyanate A 914.2 parts Dibutyltin dilaurate 0.1 part 1000.1 parts *7) Polyether polyol with 〒=3 and Mw=330; manufactured by Asahi Denka Kogyo Co., Ltd.

Using the above composition, the NCo content was 16.2% and the viscosity was 1710 cps/
Polymer Nofre Holimer X at 25°C. Note that N in this case
The C010H equivalent ratio is 1o.

Prepolymer M: Po1y-G 3020P 141.3 parts Polyisocyanate B) 858.7 parts 1000
．． 1 part *8) 1.6-hexamethylene diisocyanate,
Adduct containing terminal incyanate groups obtained by reaction with polypropylene glycol of Mw = 700 (solid content = 100 parts, Neo content = 8.5 parts, viscosity = 1
200 cps/25°C).

Using the above composition, Neo content 5.0%, viscosity '3450cpθ/2
Prepolymer X at 5°C was obtained. In addition, in this case, N C
The o10H equivalent ratio is 20.

Prepolymer Xll: Pony-G 3020 F 55.0 parts Po
'1y-G 240 55.0 parts Polyisocyanate B 890.0 parts 1000.1 parts Using the above composition, N
A prepolymer was obtained with an OO content of 7.2% and a viscosity of 2550 cps/25°C. In addition, NC010H in this case
The equivalence ratio is 2o.

Prepolymer x■: Po17-03020F 236.5 parts Polyisocyanate C! ”) 763.5 parts dibutyltin dilaurate 0.1 part 1000.1 part Mine9) 1.6-hexamethylene diincyanate and 8
An adduct containing terminal incyanate groups (obtained by reaction with a mixture of 5 molar neopentyl glycol and 15 molar polyethylene glycol (MW=400)
Solid content = 100%, NCO content = 16.0%, viscosity =
1700 cps/25°C).

Using the above composition, NCo content 11.6% x viscosity 2900C'p was prepared in the same manner as in the case of prepolymer
e/25°C Nofre Holimer X■ was obtained. Note that the N C010H equivalent ratio in this case is 2o.

Prepolymer X: Po1y-G 3020F 94.4 parts Po
1y-G 240 94.4 parts Polyisocyanate 0 811.2 parts 1000.1 parts The above composition was prepared in the same manner as in the case of Prepolymer (1), NCo content 12.31, viscosity 2550 cps/
A prepolymer XIv at 25° C. was obtained; the N0O10H equivalent ratio in this case was 2o.

Prepolymer
00%, NCO content = 37.8%, viscosity = 15 c
ps/25°C).

Using the above composition, N
Co content 13.9%, viscosity 3500 cps/25
℃ prepolymer X■ was obtained. In addition, in this case, NC0
The 10H equivalent ratio is 10.

Prepolymer X■: Pony-G 3020 F 792.4 parts Polyincyanate A 207.6 parts 100
When 0.1 part of the above composition was reacted in the same manner as in Prepolymer (1), the resulting reaction product had extremely high viscosity (unmeasurable). Note that the N 0 O 1 0 H equivalent ratio in this case is 2, and the prepolymer XV+U is outside the constituent components of the present invention.

Prepolymer Content rate 17. Steamed rice, sticky [1010cps/
Prepolymer X■ at 25°C was obtained. In addition, in this case (D
The NcO10u equivalent ratio is 60. This prepolymer X■ is not a component of the composition of the present invention.

Prepolymer min=50%, NCO content=7.7%, viscosity=
1100 cps/25°C).

Using the above composition, the NCO content was 5.4%, the viscosity was 5J-2100cps/
Prepolymer X■ at 25°C was obtained.

Pre-polymer
MDI) (solids = 100%, Noo content = 30, bar, viscosity = 200 cps/25°C).

Prepolymer XX: Plaxel 220AL ``'') 318.3 parts Polyisocyanate A 682.8 parts Dibutyltin dilaurate 0.1 part 1001.2 parts 11f13) f = 2, Mw = 2000 Nopolycaprolactone: Manufactured by Daicel Industries, Ltd. .

Using the above composition, the NCO content was 11.9% and the viscosity was 5000 cps/
Prepolymer xX at 25°C was obtained. Note that N in this case
(!010H equivalent ratio is 10.

Prepolymer xxi: PTG 400'') 258.5 parts Polyisocyanate A 741.5 parts 1000
．． 1 part *14) Polyoxytetramethylene glycol with t = 2, Mw = 1500 Nippon Polyurethane Industries Co., Ltd. Using the above composition, in the same manner as in the case of Prepolymer I, Nco content 12.9% FIJ-6000c
Prepolymer XXI of ps/25°C was obtained. Note that the N OOlo H equivalent ratio in this case is 1o.

Using the above composition and using the same method as in the case of Prepolymer 1, the NC○ content was 12.7% and the viscosity was 3850 cps.
/25°C prepolymer XIX'i was obtained.

Example 1 Prepolymer 1 100.0 parts 1.4
-butanediol 17.1 parts dibutyltin dilaurate 0.01 part 117.11 parts Of the above composition, the total amount of dibutyltin dilaurate was dissolved in the total amount of 1,4-butanediol, and then mixed with the prepolymer (■). and stirred for about 30 minutes at room temperature under vacuum.

Next, add about 34.9 of this mixture to an inner size of about 100 x 1
The mixture was gently poured into a 00 x 50 (+m) flat Teflon mold, left at room temperature under vacuum for an additional 30 minutes, and then heated at 50°C for 1 hour in a hot air circulation dryer. After leaving it to cool to room temperature for about 15 minutes, it was demolded and approximately 100'X10''X3
”(in)+7)7)wo'4ri.

Example 2 Prepolymer (1) 100.0 parts 1.4-butanediol 15.3 parts dibutyltin dilaure 0.01 part 115.31 parts
A sheet was obtained in the same manner as in Example 1 using the above composition.

Example 3 Prepolymer 1 100.0 parts 1.4
-Butanediol 10.9 parts Dibutyltin dilaurate 0.01 part 110.91 parts A sheet was obtained in the same manner as in Example 1 using the above composition.

Example 4 Prepolymer IV 100.0 parts 1
．． 4-Butanediol 9.9 parts Dibutyltin dilaure 0.01 part 109.91 parts A sheet was obtained in the same manner as in Example 1 using the above composition.

Example 5 Prepolymer V 100.0 parts 14
-Butanediol 14.6 parts Dibutyltin dilaurate 0.01 part 114.61 parts A sheet was obtained in the same manner as in Example 1 using the above composition.

Example 6 Prepolymer Vl 100.0 parts 1
．． 4-Butanediol 16.3 parts Dibutyltin dilaurate 0.01 part 116.31 parts A sheet was obtained in the same manner as in Example 1 using the above composition.

Example 7 Prepolymer ■ 100.0 parts 1.4
-butanediol 17.2 parts dibutyltin dilauret) 0.01 part Using the above composition,
A sheet was obtained in the same manner as in Example 1.

Example 8 Prepolymer ■ 100.0 parts 1.4
-Butanediol 16.4 parts Dibutyltin dilaurate 0.01 part 116.41 parts A sheet was obtained in the same manner as in Example 1 using the above composition.

Example 9 Prepolymer IX 1oo,o part 1
．． 4-Butanediol 12.1 parts Dibutyltin dilaurate 0.01 part 112.11 parts A sheet was obtained in the same manner as in Example 1 using the above composition.

Example 1O Prepolymer X ioo,o Part 1.
4-Butanediol 17.4 parts Dibutyltin dilaure 0.01 part 117.41 parts A sheet was obtained in the same manner as in Example 1 using the above composition.

Example 11 Prepolymer M 100.0 parts 1.
4-Butanediol 9.1 parts dibutyltin dilauret) 0.01 part 109.11
A sheet was obtained in the same manner as in Example 1 using the above composition.

Example 12 Prepolymer Xi 100.0 parts 1
．． 4-Butanediol 7.7 parts Dibutyltin dilaurate 0.01 part 107.71 parts A sheet was obtained in the same manner as in Example 1 using the above composition.

Example 13 Prepolymer XOI 100°0 parts 1.
A sheet was obtained in the same manner as in Example 1 using 12.4 parts of 4-butanediol and 0.01 part of dibutyltin dilaurate and 112.41 parts of the above composition.

Example 14 Prepoly-q-XN 1oO,o Part 1
．． 4-Butanediol 13.2 parts A sheet was obtained in the same manner as in Example 1 using the above composition.

Example 15 The Brepoly'v-xv ioo, o Part 1
．． 4-Butanediol 14.9 parts Dibutyltin dilaure 0.03 parts 114.93 parts A sheet was obtained in the same manner as in Example 1 using the above composition.

Example 16 Prepolymer 1 100.0 parts 1.4
-Butanediol 11.6 parts Ethylene glycol 3.9 parts Dibutyltin dilaurate 0.01 part 115.51 parts A sheet was obtained in the same manner as in Example 1 using the above composition.

Example 17 Prepolymer XX 100 , O part 1
．． 4-Butanediol 12.5 parts Dibutyltin dilaure 0.01 part 112.51 parts A sheet was obtained in the same manner as in Example 1 using the above composition.

Example 18 Prepolymer xxr ioo,o Part 1
．． 4-Butanediol 12.9 parts Dibutyltin dilaurate 0.01 part 112.91 parts A sheet was obtained in the same manner as in Example 1 using the above composition.

Comparative Example 1 Poly-G 420P, 8.91 parts Polyincyanate A 91.09 parts 1,4-butanediol 17.10 parts Dibutyltin dilaurate 0.02 parts 117.12 parts The total amounts of the above four compositions were uniformly mixed. Thereafter, a sheet was obtained in the same manner as in Example 1, but this sheet was cloudy over the entire surface and was so fragile that it would flex or break during demolding.

Note 1. The above composition has the same composition as Example 1, but in Example 1, Poly-G-420 and polyisocyanate A were reacted in advance to form a prepolymer, whereas in Comparative Example 1, The difference is that it is not made into a prepolymer. That is, Comparative Example 1 deviates from the scope of the present invention.

Comparative Example 2 Poly-G 1020P 19.17 parts Polyincyanate A 80.83 parts 1.4-'
Butanediol 15.30 parts Dibutyltin dilaure 0.02 parts 115.32 parts A sheet was obtained using the above composition in the same manner as in Comparative Example 1. It was cloudy and fragile.

Comparative Example 2 has the same composition as Example 2, but in Example 2, Poly-G 1020F and polyisocyanate A are reacted in advance to form a prepolymer, whereas in Comparative Example 2, Polyisocyanate A is reacted in advance to form a prepolymer. The difference is that it is not polymerized. That is, this comparative example 2 deviates from the scope of the present invention. Comparative Example 3 Pony-G 3020P 43. 27 parts Polyisocyanate A 56.73 parts 14-butanediol 10.90 parts Dibutyltin dilauret) 0.02 parts 110.92 parts Using the above composition, a comparative example was prepared in the same manner as in Comparative Example 1. Comparative Example 3 has the same composition as Example 3, but in Example 3, Poly-G 3020F and Bo-1 Isocyanate A were reacted in advance to form a prepolymer, whereas in Comparative Example 3, The difference is that it is not polymerized. That is, Comparative Example 3 deviates from the scope of the present invention.

Comparative Example 4 Prepolymer tone too, o part 1.4-
Butanediol 18.4 parts Dibutyltin dilaurate 1 part o, o 118.41 parts Comparative Example 5 A sheet was obtained in the same manner as in Example 1 using the above composition.
Butanediol 5.8 parts Dibutyltin dilaurate 0.01 part 105.81 parts A sheet was obtained in the same manner as in Example 1 using the above composition.

Comparative Example 6 Prepolymer XIX ioo, o part 1.4-butanediol 13.6 parts dibutyltin dilaurate 0.01 part 113.61 parts Using the above composition, a sheet was prepared in the same manner as in Example 1. Obtained.

After leaving each of the sheets obtained in Examples 1 to 16 and Comparative Examples 1 to 6 for one day at 20° C. and 65% RH, the JI No. 83 dumbbell test piece was punched out. Using this test piece, the following tests were conducted.

1 Tensile test Test model: TOM 500 (manufactured by Japan Miniature Bearing Co., Ltd.) Test temperature = 20 ± 1°C Cross head speed = 50II/M chart speed: 25ii/distance between deceptive lines = 201m Measurement items: Tensile breaking strength, tensile Elongation at break, 50% modulus, 100% modulus.

2 Weather resistance test Test model: Sunshine Geometer WE-8UN
-DC-1 type (manufactured by Suga Test Instruments Co., Ltd.) Test conditions Black panel temperature reading = 63 ± 3°C Spraying water pressure: 1
．． Okl? f/cd Spray water amount: 2.1070, 1011/aoa
Spraying time: 12 minutes out of 60 minutes (spraying times should be at equal intervals).

One irradiation time: 601 hours Total irradiation time: 2000 hours Measurement item Two-sight diagnosis of yellowing The above test results are summarized in Table 1.

Claims (1)

[Claims] 1 A large excess of aliphatic and/or alicyclic diisocyanate is reacted with an aliphatic diol having 2 to 20 carbon atoms, and an adduct containing a terminal incyanate group from which the excess diisocyanate has been removed is combined with an isocyanate group and a polyol. The equivalent ratio of hydroxyl groups R (N (!010H) is 2<R≦
The terminal incyanate group-containing urethane prepolymer obtained by reacting the urethane prepolymer with an aliphatic diol having 2 to 20 carbon atoms in a manner that satisfies the N O010H equivalent ratio of 0.8 to 1.
．． A polyurethane resin composition mixed in a proportion within the range of 5.