JPS6354539B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to a flame-resistant laminate, particularly a laminate having a core material of phenolic urethane foam, which has excellent heat resistance, dimensional stability, and the like. Conventionally, laminates have been used for ceiling materials, wall materials, and other construction materials, with a core material such as wood or plaster and a facing material such as decorative paper or iron plate, but these materials are generally heavy and have difficulty in construction. It also has the disadvantages of being hygroscopic and having low heat insulation properties. On the other hand, materials having core materials made of lightweight organic foams such as rigid polyurethane foams with good heat insulation properties have been developed, but these materials generally have the disadvantage of low fire retardant performance. A laminate with a polyisocyanurate foam as a core material and aluminum foil or plate-like material as a face material is known as a laminate with high fire retardant performance that uses an organic foam as a core material. In order to pass the flame retardant class 2 test described below, a considerable amount of flame retardant, smoke reducer, or inorganic material is added to the polyisocyanurate foam, which reduces the physical properties of the foam such as heat insulation and dimensional stability. This is unavoidable, and it is economically disadvantageous because the aluminum foil or plate-like material to be attached must have a thickness of 0.1 mm or more to be effective. The present invention uses a phenolic urethane foam manufactured using a special polyol component, removes all flame retardants from the conventional rigid urethane foam foam formulation, passes the flame retardant grade 2 test, and is inexpensive. To provide a flame-resistant laminate that can be produced by a method suitable for industrial productivity. That is, the present invention provides a laminate in which at least one side of a urethane foam is coated with a flame-resistant face material, in which the urethane foam is (a) a benzyl ether type obtained by condensing formaldehyde in an equimolar or more amount to phenol; The phenolic hydroxyl group of phenolic resin
A modified phenol resin in which 0.3 equivalent or more has been converted into alcoholic hydroxyl groups with alkylene carbonate and (b) polyisocyanate are subjected to a foaming reaction in the range of NCO equivalent/OH equivalent ≦2,
This relates to a flame-resistant laminate that is self-adhered onto the facing. The benzyl ether type phenolic resin in the present invention is prepared by using alkaline earth metal oxides, hydroxides, or organic weak acid salts such as acetic acid and naphthenic acid alone or under conditions of 1 mole or more of formaldehyde per 1 mole of phenols. , obtained by reaction under a mixed catalyst. The phenols referred to herein mean those in which one or more carbon atoms of the skeleton forming a benzene ring are directly bonded to a hydroxyl group, and also include those having other substituted bonding groups within the same structure. Typical examples include phenol, cresol, bisphenol A, and resorcinol. Further, formaldehydes are not particularly limited, but formalin and paraformaldehyde are preferred. Furthermore, the alkylene carbonate used in the present invention has the general formula: (However, R and R' are hydrogen or an alkyl group having 1 to 6 carbon atoms.) Specifically, for example, ethylene carbonate, propylene carbonate, 4-ethyl dioxolone, 4-butyl dioxolone, 4 , 5-dimethyldioxolone, 4-pentyldioxolone, 4,4'-dimethyldioxolone, etc. are used. Next, the amount of conversion of phenolic hydroxyl groups in the resin to alcoholic hydroxyl groups is as follows:
The amount is 0.3 equivalent or more, preferably 0.4 to 0.8 equivalent. If the conversion amount is 0.3 equivalent or less, the modification effect will not be exhibited. Note that if alkylene carbonate is used in excess of the equivalent amount of phenolic hydroxyl groups, unreacted alkylene carbonate or hydrolyzed glycol will be produced, which will deteriorate the heat resistance of the final cured phenol urethane product and reduce the reaction rate during curing. The object of the present invention cannot be achieved because of the delay. In the present invention, the conversion reaction of a phenolic hydroxyl group into an alcoholic hydroxyl group is carried out by adding and mixing alkylene carbonates while keeping the benzyl ether type phenolic resin, which has been concentrated in advance through a condensation reaction and a dehydration reaction, in a non-aqueous system. Not
A suitable alkaline catalyst is added at a temperature not exceeding 140°C, and the reaction is allowed to occur for several minutes to several hours. As the alkaline catalyst for denaturation, catalysts such as potassium carbonate, sodium carbonate, and calcium carbonate that open the ring of alkylene carbonate and do not generate glycol are preferable.By using these catalysts, alkylene carbonate can generate carbon dioxide gas. While doing so, the ring opens, forming an ether bond with the phenolic hydroxyl group, and the hydroxyl group is modified. The obtained modified resin is further removed under reduced pressure to remove unreacted carbonate monomers and by-produced glycol monomers, as necessary, to obtain a product. used in liquids. The polyisocyanates used in the present invention are not particularly limited, and any conventionally and commonly used polyisocyanates may be used as appropriate. Typical examples include aromatic polyisocyanates such as tolylene diisocyanate, diphenylmethane diisocyanate, crude diphenylmethane diisocyanate, etc.
Examples include aliphatic polyisocyanates such as hexamethylene diisocyanate, isophorone diisocyanate, dicyclohexylmethane diisocyanate, and the like. Particularly preferred are diisocyanates. The reaction ratio between the modified phenolic resin and the polyisocyanate is in the range of NCO equivalent/OH equivalent≦2, preferably 1.2 to 1.8. When NCO equivalent/OH equivalent exceeds 2, flyability increases. The OH equivalent here refers to phenolic and alcoholic
It concerns the total OH. Both reactions are usually carried out in the presence of a curing catalyst, foam stabilizer and blowing agent. As curing catalysts, amine catalysts such as triethylenediamine, N,N-dimethylethanolamine, N,N,N',N',N''-pentamethyldiethylenetriamine, etc., organotin catalysts such as dibutyltin dilaurate, stannous octamine, etc. ate, dibutyltin diacetate, etc. These curing catalysts are used in an amount of 0 to 10% by weight of the modified phenolic resin. The blowing agent is not limited, and general blowing agents for urethane foam can be used as they are. Specifics Examples include chlorofluorinated hydrocarbons such as trichloromonofluoromethane and dichlorodifluoromethane, and others.
Examples include methylene chloride and pentane. Examples of foam stabilizers include nonionic surfactants such as organopolysiloxane-polyoxyalkylene copolymers and silicone-glycol copolymers. The urethane foam used in the present invention is bonded to a flame-resistant face material. The flame-resistant surface material may be any flame-resistant material such as asbestos paper, glass paper, aluminum foil, various flame-resistant laminate papers, and gypsum flat boards, but asbestos paper is particularly preferred. Asbestos paper has excellent self-adhesive properties with the above-mentioned urethane foam, and is lightweight and economical. The thickness of asbestos paper
Approximately 100 to 500 g/m ² is suitable. In the present invention, the urethane foam and the flame-resistant surface material are self-adhesive. Self-adhesion is easily achieved by overlapping the urethane foam core material with the face material during formation, so there is no need to use a separate adhesive to bond the urethane foam core material and the face material, resulting in excellent industrial productivity. There is. At least one flame-resistant facing material shall be attached to any surface that may come into contact with flames. The urethane foam used in the present invention is itself extremely flame retardant and exhibits excellent flame retardancy without the use of special flame retardants, flame retardants or smoke reducers, but without the use of flame resistant face materials. It is not possible to obtain a product that passes the JIS-A-1321 flame retardant class 2 fire protection test. Conversely, even if asbestos paper or the like is used as a surface material to protect the surface of conventional hard urethane foam or polyisocyanurate foam, it will not pass the second class flame retardant test unless a large amount of flame retardant is used. In addition, the use of such flame retardants impairs the insulation properties and dimensional stability of the foam.
Moreover, mechanical properties are deteriorated. The present invention will be explained below with reference to Examples. Example 1 600 kg of phenol and 204 kg of 47% formalin
1.4 kg of lead naphthenate was added, the temperature was raised, and the mixture was reacted at 100 to 103°C for 4 hours. The obtained resin was introduced into a continuous concentrator with an L/D of 1000, and the outlet of the tube was placed in a flash chamber kept at 125°C while the jacket of the tube was heated with 3.5 kg/cm ² of steam. guide the flash chamber.
The pressure was reduced to 60 mmHg, and while unreacted monomers and water were removed from the system, only the resin liquid was separately taken out of the system to obtain a benzyl ether type phenol resin liquid (hereinafter referred to as resin liquid A). Resin liquid A had the characteristics shown in Table 1.

[Table] Next, 260 kg of resin liquid A and 110 kg of ethylene carbonate were charged into a reaction vessel, 0.3 kg of K ₂ CO ₃ was added, and the mixture was reacted at 110°C for 50 minutes. As the reaction progresses, carbon dioxide gas is generated, so while removing it from the system,
After the reaction was completed, the monomer was removed under reduced pressure to obtain a modified resin (hereinafter referred to as resin liquid). Table 2 shows the properties of the resin liquid. Table 2 Viscosity (20℃ cps) 4200 OH number (mgKOH/g) 407 Average molecular weight 324 Nonvolatile content (%) 72 Moisture (%) 0.9 Free phenol (%) 4.9 Free formaldehyde (%) 0.1 Monomer and glycol in resin liquid When measured by gas chromatography, the content was 2% ethylene carbonate and 0% glycol, and the modification rate was 0.56 mol per mol of phenolic hydroxyl group. Incidentally, each item in the above examples was measured based on the following measuring method. Viscosity: Based on BH type viscometer. Free phenol...liquid chromatography free formaldehyde...by hydrochloric acid/hydroxylamine method. Nonvolatile content: 180°C x 1 hour Evaporation average molecular weight: Based on vapor pressure osmosis method. Methylol group/ether group...by IR method OH value...by acetylation method. Moisture: According to the Karl-Fitscher method. Methylol group equivalent: 10 g of phenolic resin and 20 g of phenol (containing 0.2 wt% PbO) were reacted at 115 to 120°C for 90 minutes, and after cooling, water was removed by the Karl Fischer method and free formalin was measured by the hydrochloric acid hydroxylamine method. Find it by (P+R)×RRW×10 ^-2 −(P+R)(RF−RRF)×18×
18 ^-2 /30-R x RW x 10 ^-2 x P x PW x 10 ^-2 /R x 18 x 100 P: Amount of added phenol (g) R: Amount of resin (g) RF: Free formalin in resin (% ) RW: Moisture in resin (%) PW: Moisture in added phenol (%) RRF: Free formalin in reactant (%) RRW: Moisture in reactant (%) Next, using this resin liquid, in formulation A. A board was prepared by free foaming in a box and foaming in a mold according to recipe B. These foam physical property values are shown in Table 3. Prescription A Parts by weight Resin liquid 100 T-12 0.3 L-5420 1.5 S-1 16 MR-200 NCO equivalent/OH equivalent = 1.2 Prescription B Parts by weight Resin liquid 100 T-12 0.3 L-5420 1.5 S-1 60 MR- 200 NCO equivalent/OH equivalent = 1.2 Here, T-12 is a product of M&T Chem Co., Ltd. Dibutyltin dilaurate L-5420 is a product of Nippon Unicar Co., Ltd. Organopolysiloxane polyoxyalkylene copolymer S-1 is a product of Daikin Industries Co., Ltd. Daiflon S-
1; Trichloromonofluoromethane MR-200 is a product of Nippon Polyurethane Kogyo Co., Ltd. Crude diphenylmethane diisocyanate (Millionate MR200) NCO content 31% Free foaming in the box is achieved after high-speed stirring for approximately 10 seconds at a blending ratio of 200 g of resin liquid. , placed in a 25cm square box and allowed to foam freely. Also, when creating a board in a mold, the mixing ratio is approximately 20g of resin liquid.
After stirring at high speed for 10 seconds, place in a 30cm x 30cm x 20mm mold preheated to approximately 55℃, place a top lid preheated to approximately 55℃, secure the mold and lid firmly with clamps, and place the mold into a mold. It was created by foaming inside.

[Table] Next, in Examples 2 to 7, laminates using resin liquid will be introduced. Example 2 Aspal (asbestos paper manufactured by Jujo Paper Co., Ltd.) cut into 30 cm squares and heated to approximately 55°C in advance
100g/m ² ) heated to approximately 55℃ in a mold (30cm in length and width,
(depth 20mm). A resin liquid prepared by formula C at a blending ratio of 20g of resin liquid,
Add a specified amount to the mixed solution of T-12, S-1, and L-5420.
Immediately after adding MR-200 and stirring at high speed for about 10 seconds, the mixed stock solution is poured into the mold. Place aspar that has been preheated to about 55°C above the injection stock solution, then place the top lid that has been preheated to about 55°C, and firmly fix the mold and the lid with a clamp. Leave it at room temperature for about 10 minutes, then remove it from the mold and make it 30cm x 30cm x
A 20 mm laminate was produced. The cross-sectional structure of the obtained laminate is shown in FIG. In the figure, 1 is asbestos paper,
2 shows a layer of phenolic urethane foam.
The combustion test results of this laminate are shown in Table 4. Formulation C Resin liquid I 100 parts by weight T-12 0.4 parts by weight L-5420 3 parts by weight S-1 60 parts by weight MR-200 NCO equivalent/OH equivalent = 1.6

【table】

[Table] Examples 3, 4 and 5 The following laminates were obtained in the same manner as in Example 2 except that the face material was changed. In Example 3, asparallel (100μ
Example ⁴ Laminate in which the polyethylene film layer was adhered to the urethane foam layer using
is a laminate (with the aluminum layer as the outermost layer) using aluminum foil (thickness 20μ) laminated to aspar (100g/m ² ) via polyethylene film (thickness 20μ) as a face material. Example 5 is a laminate using aluminum with a thickness of 150 μm as the face material. The combustion test results of these laminates are shown in Table 5.

[Table] Examples 6 and 7 In Example 6, the surface material is a 3mm thick flexible board made of cemented asbestos, and the back material is a 50μ
This is a laminate using glass paper (60 g/m ² ) laminated with a thick polyethylene film. This configuration is shown in FIG. In the figure, 2 is a urethane foam layer, 3 is a polyethylene film layer, and 4 is a polyethylene film layer.
5 indicates a glass paper layer and 5 indicates a flexible plate. The manufacturing method is the same as in Example 2.
That is, a flexible plate was set in a mold, a mixed solution of prescription C was poured onto it, and a glass paper was set above the injection stock solution. Example 7 is a laminate using glass paper (60 g/m ² ) laminated with a 9 mm thick gypsum flat board as the surface material and a 50 μ thick polyethylene film as the back material (polyethylene film and urethane foam are bonded together). ). The manufacturing method is the same as in Example 6. The combustion test results of these laminates are shown in Table 6.

[Table] Example 8 The relationship between the modification ratio of a benzyl ether type phenolic resin modified with ethylene carbonate and the flyability of the foam was investigated. The modified phenolic resin was synthesized according to Example 1. On the other hand, the foam was obtained by free foaming in a box using Formulation D. These results are shown in Table-7. Formulation D Modified phenolic resin 100 parts by weight T-12 0.3 parts by weight L-5420 1.5 parts by weight S-1 25 parts by weight MR-200 NCO equivalent/OH equivalent = 1.2 Next, using the resin liquid, calculate the NCO equivalent and OH equivalent. Boards were prepared by in-mold foaming according to Example 1 with different ratios, and their flyability was examined. The results are shown in Table-8.

[Table] Flyability: Rub the surface of the foam strongly with your fingers, and mark with an x if powder is generated, or mark with an ○ if it does not.

[Table] Flyability: Rub the surface of the board strongly with your fingers, mark the item that generates powder with an
Items that do not survive are marked with ○.

[Brief explanation of the drawing]

FIGS. 1 and 2 are cross-sectional views of one embodiment of the flame-resistant laminate of the present invention. In the figure, 1 is asbestos paper, 2 is a urethane foam layer, 3 is a polyethylene film, 4 is glass paper, and 5 is a flexible board.

Claims (1)

[Scope of Claims] 1. A laminate in which at least one side of a urethane foam is coated with a flame-resistant face material, wherein the urethane foam contains (a) benzyl obtained by condensing formaldehyde in an equimolar or more amount to phenol; The phenolic hydroxyl group of ether type phenolic resin
A modified phenol resin in which 0.3 equivalent or more has been converted into alcoholic hydroxyl groups with alkylene carbonate and (b) polyisocyanate are subjected to a foaming reaction in the range of NCO equivalent/OH equivalent ≦2,
This is a flame-resistant laminate that is self-adhered to the surface material. 2. The flame-resistant laminate according to item 1, wherein the flame-resistant facing material is asbestos paper.