JP3338133B2 - Surface layer-forming resin composition for calender roll - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a surface layer-forming resin composition for a calender roll. More specifically, when used as a surface layer-forming resin of a calender roll, and when run in contact with a metal roll, paper, magnetic tapes and other calendered materials have excellent smoothness and small compression set. This is a surface layer-forming resin composition capable of obtaining a calendar roll having excellent durability.

[0002]

2. Description of the Related Art Conventionally, cotton rolls, paper rolls, wool rolls and the like have been used as surface layer-forming compositions for calender rolls. In recent years, in order to improve these drawbacks, calender rolls having a surface layer formed of a resin such as a polyisocyanurate resin, urethane resin, or epoxy resin (Japanese Patent Publication No. 3-50038) or a thermosetting liquid which is liquid during molding. A calender roll in which a liquid thermosetting elastomer which is incompatible with the thermosetting resin is micro-dispersed in a thermosetting resin is known (JP-A-1-2823).
No. 98).

[0003]

However, in the case of rolls formed of these materials on the surface, if the hardness of the cured resin is reduced in order to obtain the smoothness of the surface of the object to be calendered, the compression set becomes large and the durability as a roll is increased. However, heat resistance or impact resistance was impaired, and conversely, if the hardness was increased to reduce the compression set, the surface smoothness of the calendered object was deteriorated.

[0004]

Means for Solving the Problems The present inventors have solved the above problems, that is, to improve the surface smoothness of a calendered object,
As a result of intensive studies to reduce the compression set, the inventors have found that the problem can be solved by mixing a solid urethane oligomer in the epoxy resin composition, and have reached the present invention. That is, the present invention provides a liquid epoxy resin (A), an aromatic amine-based curing agent (B), and an aromatic diamine (C1).
And a reaction product (C) of a urethane prepolymer (C2) and a surface layer-forming resin composition for a calender roll.

As the liquid epoxy resin (A) used in the present invention, bisphenol type liquid epoxy resins such as bisphenol A type liquid epoxy resin, bisphenol F type liquid epoxy resin, bisphenol AD type liquid epoxy resin, diglycidyl phthalate, etc. Glycidyl ester type liquid epoxy resin, glycidylamine type liquid epoxy resin such as triglycidyl paraaminophenol, tetraglycidyl diaminodiphenylmethane, tetraglycidyl metaxylylene aniline, diglycidyl aniline, diglycidyl-o-toluidine, 1,6 hexamethylene glycol diglycidyl Ether, neopentyl glycol diglycidyl ether, polyethylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether , Glycerol polyglycidyl ether, polyglycidyl ether type liquid epoxy resin, and mixtures thereof, such as trimethylolpropane polyglycidyl ether, and the like. Of these, preferred are bisphenol A type liquid epoxy resin, bisphenol AD type liquid epoxy resin, bisphenol F
Liquid epoxy resin and a mixture of these with a glycidylamine liquid epoxy resin.

[0006] The amount of (A) in the composition of the present invention is usually 50
~ 80% by weight.

The aromatic amine-based curing agent (B) used in the present invention includes aromatic primary amine-based curing agents such as diaminodiphenylmethane, metaphenylenediamine, diaminodiethylphenylmethane, diaminodimethylphenylmethane, and diaminodiphenylsulfone. Aniline, and formalin condensates thereof, and the like. As an aromatic secondary amine-based curing agent, an epoxy compound such as butyl glycidyl ether or phenyl glycidyl ether of an aromatic primary amine, an alkylene oxide,
Modified products with acrylonitrile, etc., N-alkylanilines, and formalin condensates thereof, and the like,
These can be used alone or in combination of two or more. Of these, preferred are aromatic secondary amine-based curing agents, and particularly preferred are those containing a formalin condensate of N-methylaniline. The number average molecular weight of the formalin condensate of N-methylaniline is usually 226 to
850.

[0008] The content of (B) in the composition of the present invention is usually 15 to 60% by weight.

The urethane prepolymer (C2) is (C1)
An oligomer having a functional group capable of reacting with a polymer such as a polypropylene glycol-based urethane prepolymer and a polyoxytetramethylene glycol-based urethane prepolymer. Of these, preferred are polyoxytetramethylene glycol-based urethane prepolymers having a number average molecular weight of 3,000 to 30,000, and more preferably 5,000 to 10,000.
Is a polyoxytetramethylene glycol-based urethane prepolymer.

The molecular weight of the urethane prepolymer is 3,000
If it is less than 0, the effect of reducing the compression set is not sufficient, and 3
If it exceeds 000, phase separation occurs in the epoxy resin, making it difficult to obtain a homogeneous cured product.

In the present invention, (C1) forming the reactant (C) includes those described as the aromatic amine-based curing agent (B).

The amount of (C) in the composition of the present invention is usually from 1 to
It is 15% by weight, preferably 2 to 9% by weight, more preferably 3 to 7% by weight.

When the amount of (C) is 1% by weight or less, the effect of reducing the hardness of the cured product is not sufficient, and when it is 15% by weight or more, the compression set becomes large.

If necessary, a filler or the like may be added to the composition of the present invention. Specific examples include iron powder, iron oxide powder, aluminum powder, copper powder, stainless steel powder, silica powder,
Examples include talc, calcium carbonate, and titanium oxide.

The amount in these compositions is usually from 0 to 70% by weight.

Further, various other additives may be added to the composition of the present invention. For example, an antifoaming agent, an antisettling agent, and a curing accelerator may be added.

The amount in these compositions is usually from 0 to 3% by weight.
It is.

The composition of the present invention is usually composed of two components, a main component containing (A) and a curing agent containing (B) and (C). It may be added to any of the component and the curing agent component.

By forming a cured layer of the composition of the present invention on the surface of an iron core or the like, it is excellent in heat resistance and low in hardness. Since a calendered object such as a tape is excellent in smoothness and small in compression set, a calender roll excellent in durability can be produced. As a method for forming a layer obtained by curing the composition of the present invention on the surface of an iron core or the like, there are a direct casting method and a centrifugal casting method.

A typical example of preparing a calender roll using the composition of the present invention will be described below. In the direct casting method, after the surface is blasted, an iron core coated with an adhesive or treated with an adhesive layer impregnated with glass cloth, carbon fiber or the like is set in a resin casting mold.
After injecting the resin composition of the present invention whose temperature has been controlled to ℃ 80 ° C. and heat-curing to complete the curing to obtain a surface layer, the surface is polished to obtain a calender roll. In the centrifugal molding method, after the above surface layer is cured in a centrifugal molding machine, the obtained cylindrical surface layer is bonded to the iron core treated as described above, and the surface is polished to obtain a calender roll.

The method of mixing the composition of the present invention includes:
(A), (B), and (C) may be mixed at the same time,
Further, since (C) is a solid, a solution prepared by dissolving (C) in (B) may be prepared in advance, and this may be mixed with (A). Usually, (B) and (C1) are the same. And (B)
Is used in a large excess with respect to (C2), so that a predetermined amount of (C2) is reacted in (B) to form a mixture of (B) and (C) in one step, and this is mixed with (A) May be mixed.

[0022]

EXAMPLES Hereinafter, the present invention will be described more specifically with reference to examples, but the present invention is not limited to these examples. Parts in the examples are parts by weight.

Production Example 1 Tetraglycidyl diaminodiphenylmethane [trade name Sumiepoxy ELM-434, manufactured by Sumitomo Chemical Co., Ltd.] 419
581 parts of a bisphenol AD type epoxy resin [trade name: Epomic R-710, manufactured by Mitsui Petrochemical Co., Ltd.] was uniformly dissolved in the mixture to obtain a viscous liquid. This is designated as main agent (1).

Production Example 2 Tetraglycidyl diaminodiphenylmethane [trade name: Sumiepoxy ELM-434, manufactured by Sumitomo Chemical Co., Ltd.] 300
In a portion, 700 parts of a bisphenol A type epoxy resin [trade name: Epicoat 828, manufactured by Yuka Shell Epoxy Co., Ltd.] was uniformly dissolved to obtain a viscous liquid. This is designated as main agent (2).

Production Example 3 Tetraglycidyldiaminodiphenylmethane [trade name: Sumiepoxy ELM-434, manufactured by Sumitomo Chemical Co., Ltd.] 380
620 parts of a bisphenol A type epoxy resin [trade name: Epikote 828, manufactured by Yuka Shell Epoxy Co., Ltd.] was uniformly dissolved in the resulting mixture to obtain a viscous liquid. This is designated as main agent (3).

Production Example 4 Tetraglycidyl diaminodiphenylmethane (trade name: Sumiepoxy ELM-434, manufactured by Sumitomo Chemical Co., Ltd.) is used as the main agent (4).

Production Example 5 Formalin condensate of aniline [trade name MDA-150,
Mitsui Toatsu Co., Ltd.] 207 parts, N-methylaniline formalin condensate (number average molecular weight 270) 700 parts uniformly dissolved in polyoxytetramethylene glycol having a molecular weight of about 3,000 [trade name PTMG- 3000, manufactured by Sanyo Chemical Industries, Ltd.] per mole of tolylene diisocyanate [trade name: TDI-80, Nippon Polyurethane Co., Ltd.]
The reaction was carried out with 93 parts of a urethane prepolymer [this is referred to as oligomer (1)] reacted with 1.5 mol to obtain a viscous liquid. This is designated as a curing agent (1).

Production Example 6 Formalin condensate of aniline [trade name MDA-150,
A product obtained by uniformly dissolving 207 parts of 700 parts of a formalin condensate of N-methylaniline (number average molecular weight 270) is referred to as a curing agent (2).

Production Example 7 Urethane prepolymer [trade name: Samprene P-663L, manufactured by Sanyo Chemical Industry Co., Ltd.] per 100 parts of formalin condensate of N-methylaniline (number average molecular weight: 270) 20
The cured part is referred to as a curing agent (3).

Production Example 8 Formalin condensate of aniline [trade name MDA-150,
Manufactured by Mitsui Toatsu Co., Ltd.] as the curing agent (4).

Example 1 65 parts of a curing agent (1) and an antifoaming agent [trade name: Dappo SN-34] were used for 100 parts of a base material (1) each controlled at 50 ° C.
8, San Nopco Ltd.] 0.1 parts are uniformly mixed and defoamed under reduced pressure, and this is 10 mm × 120 mm × 120 m
m, and then cured at 80 ° C. for 4 hours, then released from the mold, and further cured at 120 ° C. for 2 hours.
It was post-cured at 50 ° C. for 4 hours to obtain a plate-shaped cured resin layer-forming resin for a calender roll.

Example 2 A curing agent (1) 60 parts and an antifoaming agent [Dappo SN-348 (trade name), San Nopco Co., Ltd.]
Manufactured by using 0.1 part of Example 1 to obtain a plate-shaped cured resin-forming piece for a surface layer for a calender roll.

Example 3 62 parts of a curing agent (1) and an antifoaming agent [Dappo SN-348 (trade name), San Nopco Co., Ltd.
Manufactured by using 0.1 part of Example 1 to obtain a plate-shaped cured resin-forming piece for a surface layer for a calender roll.

Comparative Example 1 Based on 100 parts of the base material (1), 59 parts of a curing agent (2) and an antifoaming agent [Dappo SN-348 (trade name), San Nopco Co., Ltd.]
Manufactured by using 0.1 part of Example 1 to obtain a plate-shaped cured resin-forming piece for a surface layer for a calender roll.

Comparative Example 2 Based on 100 parts of the base material (1), 34 parts of a curing agent (4) and an antifoaming agent [Dappo SN-348 (trade name), San Nopco Co., Ltd.]
Manufactured by using 0.1 part of Example 1 to obtain a plate-shaped cured resin-forming piece for a surface layer for a calender roll.

Comparative Example 3 Example 1 was repeated using 112 parts of the curing agent (3) and 0.1 part of an antifoaming agent [Dappo SN-348 (trade name) manufactured by San Nopco Co., Ltd.] with respect to 100 parts of the main agent (4). Thus, a plate-shaped cured resin layer-forming resin for a calender roll was obtained.

Using the resin for forming a surface layer for a calender roll of Examples 1 to 3 and Comparative Examples 1 to 3, the results of measurement of compression resilience, hardness, heat resistance and impact strength, which are the basic characteristics of the calender roll, are shown. The results are shown in Table 1.

[0038]

[Table 1]

Compression set: In the Rockwell hardness test method for plastics specified in JIS K 7202, an M scale, that is, a steel ball indenter having a diameter of 6.350 mm was used.
It is the amount represented by the penetration depth h of the indenter when a test is performed according to the test method with a reference load of 10 kgf and a test load of 100 kgf. Shore D hardness: Specified in ASTM D2240. Heat deformation temperature, impact strength: also specified in JIS K 6911.

As is clear from Table 1, the resin for forming a surface layer for a calender roll according to this embodiment has low hardness, high impact resistance, small compression set, and sufficient heat resistance when used as a calender roll. It was found to have the nature.

[0041]

The composition of the present invention is excellent in heat resistance and impact strength, and has low hardness, so that when it is run in contact with a metal roll, the object to be calendered, such as paper or magnetic tape, becomes smooth. The present invention can provide a surface layer-forming resin composition for a calender roll which is excellent and has excellent durability due to small compression set.

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) C08L 63/00-63/10 C08G 59/50 C08L 75/02 D21G 1/00-1/02

Claims (3)

(57) [Claims] 1. A surface layer for a calender roll comprising a liquid epoxy resin (A), an aromatic amine-based curing agent (B), and a reaction product (C) of an aromatic diamine (C1) and a urethane prepolymer (C2). Formable resin composition. 2. The method according to claim 1, wherein the aromatic amine curing agent (B) is aromatic 2
The composition according to claim 1, comprising a secondary amine-based curing agent. 3. The urethane prepolymer (C) is a polyoxytetramethylene glycol urethane prepolymer having a number average molecular weight of 3,000 to 30,000.
Or the composition according to 2.