JPH02199190A - Application of impregnated mica paper composition for covering structural element,and structural element thus obtained - Google Patents

Abstract

PURPOSE: To obtain an impregnated mica paper composition for lowly heat- generating fireproof coatings for use on structure elements, especially ones used in places where they need conforming to severe regulations on fire protection by impregnating mica paper with a specified % of a thermosetting or thermoplastic resin or an inorganic binder.

CONSTITUTION: A structure element having a fireproofing coating based on mica paper impregnated with 5-40 wt.% thermosetting resin, especially a polyimide, phenol, epoxy, silicone or bismaleimide resin, or thermoplastic resin, especially polyester imide, polyester sulfone or polyester ketone resin or an inorganic binder, especially a silicate or phosphate binder, conforming to ATS specification 10000-001 and direction 25 (O.S.U. chamber) and having lowly heat-generating properties. The impregnated mica paper composition is used as a lowly heat- generating fire-protecting coating for use in especially the aircraft industry, the automobile industry and applications, such as interior decoration, to which severe regulations on fire protection needs to be applied.

COPYRIGHT: (C)1990,JPO

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides structural elements, in particular low heat rel.
The industrial environment is concerned with the use of impregnated strength paper compositions as antifire coatings with Increasing efforts are being made on the reactivity and fire resistance of materials used in , large complex structures occupying high occupancy, and in the petroleum industry.

Particularly in the aircraft industry, new standards call for many special and stringent standards. For example, 19 regarding heat release.
Directive FAR 25 (Amendments 25-61) issued in 1986 (heat generation test) and Directive FAR 25 (Amendments 25-66) issued in 1988, also regarding heat release, Federal Aviation Atomic Disposition, and Fire Smoke. - Standard ATS 10000-001 (Issue 1 and 5) published in 1979 with the title of Toxile Testing Standards can be cited.

The exothermic test consists in measuring the total or instantaneous maximum amount of heat emitted in a short period of time by a sample of a certain size when exposed simultaneously to a flame and a well-defined intense thermal radiation.

The limits for the heat emitted in certain devices, i.e. combustion chambers, as devised by the Ohio State University, are standardized by the Federal Aviation Administration, Department of Opportunity, as follows: August 1988: Ten maximum: 100%ll/-a August 1990: Ten maximum = 65 wise/d Other criteria selected were more conventional: flame retardancy, smoke density. and smoke toxicity.

Mica-based products consisting of mica paper and binders are well-known and are used today in many industrial fields (cable manufacturing, electrical household appliances, dielectric open circuits, etc.) especially due to their excellent heat resistance. .

One of the properties of mica, which is an ore of the pulsinosilicate group in particular, is its excellent resistance to temperatures up to 600°C in the case of muscovite and 900 to 1000°C in the case of phlogopite. .

In order to be able to use mica, the base ore (scrap) is converted into binder-free mica paper, and this mica paper is reinforced with a binder so that it can be used (mica-based product). It should be noted that the mica flakes in the mica paper are oriented parallel to the plane of the paper.

Document 10 G 4, Abstract Pre-Chin Op.
The Institute of Paper Chemistry Volume 55 (1984) No. 2, Page 242, A22
56 (see JP-A-58-102417), the application of fire-resistant fiber-reinforced mica paper containing a binder based on silicone resin is known in the field of manufacturing safety insulated electrical cables. The problem is to maintain the electrical resistance at a sufficient level for as long as possible to ensure adequate insulation for as long as possible when the cable encounters a fire.

0B-A 2,141,455 describes a decorative covering consisting of a fire-resistant paper sheet. In fact, it contains fillers such as mica 15-90% by weight and organic fibers 5-30% by weight.
and paper with a fire-resistant structure containing 0 to 20% by weight of a binder consisting of a resin, which is common in this field. Firstly, this document does not describe silicone resins as a binder, and secondly, it describes papers containing randomly oriented mica in the form of fillers (in contrast to mica papers). (in this case the flakes are oriented parallel to the plane of the paper); this composition clearly requires the use of fibers to ensure adhesion of the paper.

However, these documents do not describe the use of coatings for structural elements that withstand fire according to the aforementioned criteria and under the conditions of the aforementioned tests while releasing a minimum amount of heat.

It is an object of the present invention to provide a suitable coating which, when applied to structural elements, renders them resistant to fire so that they meet the aforementioned criteria.

According to the invention, thermosetting resins, in particular resins based on polyimides, phenolics, epoxies, silicones or bismaleimides, or thermoplastic resins, in particular based on polyester-imides (PEI), polyester-sulfones (PUS) or polyester-ketones, can be used. or an inorganic binder, especially a silicate or phosphate binder5
When provided with a ˜40% impregnated mica paper coating, the structural elements meet the aforementioned criteria.

In fact, it has been confirmed that mica is inert and resistant to flame. In particular, it was confirmed that phlogopite has very high flame resistance and does not react up to temperatures in the 900°C range.

It has also been found that relatively low proportions of impregnating resin are sufficient for mica paper compared to other textures such as glass, aramid and similar fabrics or non-wovens. A proportion of the order of 5-40%, especially 10-15%, is sufficient to saturate mica paper, whereas other tissues require 3-4% for saturation.
Requires more than twice as much resin.

Of relevance here are therefore especially composite materials which have very good flame resistance and emit relatively little smoke and heat.

Surprisingly, a structural element coated in this way withstands the above-mentioned tests, whereas without a coating it does not withstand the tests.

Furthermore, mica, particularly impregnated mica paper, as used in accordance with the present invention, can easily be used in sheet or tape form.

The coating may also consist of a mica paper sheet or tape applied to a support such as a woven or non-woven glass, aramid, carbon or other fiber based support which is to be placed over the structural element.

Adhesion of mica paper to the support or adhesion of the coating to the element to be protected is known per se, emitting reduced heat when exposed to fire and emitting little or no smoke when burned. This should be ensured with a suitable adhesive. One can therefore aim for a self-adhesive coating that is sufficient to apply to the element one wishes to protect.

It is also possible to use mica paper containing a binder in the B stage (partially polymerized) and to adhere the coating to the structure to be protected or to the support during subsequent curing.

According to a particularly preferred embodiment, a silicone resin is used as binder for the squid paper. In fact, it has surprisingly been found that a squid-based product consisting of mica paper and silicone resin has surprising behavior when exposed to high temperatures.

In practice, the test was carried out with the help of a differential scanning calorimeter (DJ, C,), an instrument for thermal analysis that allows to measure the amount of heat released or absorbed by a sample of the product subjected to a heating program. went.

This test is very similar to the O, S, O, chamber exothermic test described above.

The sample in this case is subjected to temperature effects as a whole since it is placed in an audan, while 0, S. U. In the chamber, extremely large samples are subjected to intense thermal radiation and flame.

The results of the conducted tests are expressed in cal/Ji' and can be easily converted to kW·min/d if the weight of the product per square inch for a given thickness is known.

This surprising behavior was detected during the analysis of O, S, C, L[
There is.

Figure 1 shows the results of tests on beams, S and C.

Figure 2 shows 0. The results of tests in S, U and chambers are shown.

FIGS. 3 and 4 show Example 5 of [0. S, υ.

The results of the chamber test are shown.

5 and 6 show the results for Example 6.

Test Description Analysis is carried out using Perkin-Elmer (trademark) D, S, C, analysis conditions: Sample amount: 10-20 Da Temperature rise rate - °C/min Under air Analysis temperature: 30-700 °C Organic resin, In particular, when methyl silicone resin was analyzed under air, the following results were found with a low intensity exothermic peak (30 cd/11') in the 2280 °C band; related to the rearrangement of the silicone structure; An even larger exothermic peak (lo OOcat/11 units) is associated with the oxidation reaction of the silicone resin.

Moreover, during the course of the binder-free mica paper paste, S, C, no exothermic peaks were detected, which is normal and gives the constancy of mica at temperature.

On the other hand, ocular heat drift is observed.

Furthermore, in the case of muscovite-based mica paper, a more pronounced endothermic rise 9 is found in the 680° C. band (this is due to water quenching by the muscovite).

When a mica-based product consisting of mica paper and silicone resin was subjected to the same test, it was surprisingly seen that the exothermic peak in the 480° C. band associated with the oxidation reaction of the silicone resin disappeared.

For example, during DJ, C, analysis of a muscovite-based mica paper impregnated with 12% of catalyzed methyl silicone resin (same as described above), the following is observed: Strong exothermic peak, which is related to the dislocation of the silicone structure; slight endothermic drift up to about 450° C., comparable to the endothermic drift that occurred in the case of binder-free mica paper; more pronounced endothermic drift from above 450° C.

This is certain in the case of mica papers impregnated with silicone resins, which may or may not have been previously polymerized.

By comparison, 349/d glass fabric glue impregnated with the same methyl silicone resin, S, C, analysis shows two exothermic peaks characterizing the resin.

FIG. 1 shows a graph of the O, S, C test results as described above. In the figure, (1) shows the curve obtained using methyl silicone resin; (2) shows the curve obtained using binder-free squid paper; (3) shows the curve obtained using methyl silicone resin. (4) shows the curves obtained using mica paper impregnated with a proportion of 12% by weight of methyl silicone resin; (4) using mica paper impregnated with a proportion of 12% by weight of methyl silicone resin and polymerized for 1 hour at 230 °C in a L1 hot press; The resulting curve is shown.

Other thermogravimetric analyzes confirmed these results.

0,S. U. The results in the chamber also confirmed a certain endotherm (see Figure 2). These surprising results clearly indicate that L-C is highly advantageous for the use of mica-based products consisting of silicone resin and mica paper in the aforementioned fields, namely the aviation sector! Yes, this is 0. S. U. It is advantageous for the production of structural elements that must pass exothermic tests in chambers and must withstand fire.

The invention will be explained in further detail in the following examples.

Example 1 A flat panel for the interior of an aircraft cabin was constructed from a honeycomb core made of glass fibers impregnated with phenolic resin, onto which the glass fibers impregnated with phenolic resin were bonded by a double-sided ATIO type film from 3M. I made it.

Sheets of mica paper impregnated with phenolic resin were adhered to both sides of the sandwich panel thus formed using the same type of adhesive film as described above.

The impregnated mica paper clearly increased the fire resistance of the combination and significantly reduced the heat generation during the standardized combustion chamber heat generation test devised by the Ohio State University mentioned above.

Example 2 Example 2 A skew-type structure for the interior of an aircraft, such as a curved panel, was made with windows, baggage locker seat packs, etc. made in a suitably shaped mold.

A mica paper lined with 349/d thin glass fabric and impregnated with Stage B epoxy resin at 20-25% by weight was carefully placed into the mold.

Next, three layers of 2409/d glass fabric, also impregnated with epoxy resin at a rate of 55% from stage B, were placed.

The mold was then closed and the whole was pressure cured for 90 minutes at 60°C.

A decorative sheet giving the desired appearance to the panel in question was then joined by adhesive.

This made the rigid structure suitably resistant to fire and particularly to heat generation when simultaneously exposed to flame and thermal radiation in the Ohio State University Standard Combustion Chamber.

Example 3 A skew structure was made for the purpose of manufacturing kerosene tanks for air transportation.

1 with the phenolic resin already in the stage in a suitably shaped mold.
Mica paper impregnated at a rate of 4% was carefully placed. Then, in stage B, two layers of soog7-glass fabric impregnated with phenolic resin at a rate of 58% were placed.

Next, the mold was closed and pressure curing was performed. After this treatment, a structure with a particularly non-combustible and mechanically strong curved surface was obtained.
This made it possible to construct a kerosene tank element.

Example 4 Skew structures were made from glass fabric impregnated with polyamide resin by low pressure molding.

This structure could be used as internal cladding for aircraft, especially for side panels, ceilings, etc.

An 8 077/d miter paper impregnated with a silicate-based inorganic resin in a proportion of about 18 parts by weight was adhesively bonded to the structure thus obtained using a silicate-based adhesive.

The whole was covered with decorative paper bonded with silicate glue.

This structure was non-combustible and gave off the least amount of heat per unit surface area during the tests described above, especially in the O, S, U, chamber.

Example 5 A panel known as Hyperlam LF Grade 5 (obtained from Civer Geigy) was made having a thickness of 10 fi.

The panels were subjected to O, S, U, and chamber tests, and the results are shown in FIG.

The following results were found: Total heat generation 56.43kW-min/-1 and Maximum heat generation 51.98kW-min/WI.

A m1canite barrier made from mica paper and 12% polymerized silicone resin.
Next, adhesive bonding was performed using Permabond E26 (trade name) adhesive.

Tests in the two, S, and U chambers yielded the graph in Figure 4, in which it can be seen that the heat released was significantly reduced.

The actual results were as follows: Total heat release: 19.87 layers w-min/d Maximum heat release: 47.4 ehw-min/Wl The heat is released with a significant delay and acts as a retardant or thermal barrier. It turned out to be completely inert mikanai.

Example 6 Product name N0Ifll impregnated with phenolic resin! A honeycomb panel with an X was made.

O.S. U. The results of the tests carried out in the chamber are shown in Figure 5, namely total heat release: 47.8 thw-min/d maximum heat generation:
4a, sahenemy/ti.

Protective mica night plates made from mica paper containing 12% of polymerized silicone resin were then adhesively bonded to both sides of the honeycomb. The adhesive used was also made from silicone. A new test of this assembly was performed at 0.3. The results obtained are shown in Figure 6: Total heat generation: zt4yi_min/Wt Maximum heat generation: ztask_min/d The protective effect of icanite, which is completely inert from the viewpoint of heat generation, is observed.

[Brief explanation of the drawing]

Figure 1 shows the results of the beam, S, and C tests, and Figure 2 shows the results of the 0.
! 9. 3 and 4 show the results of the test in the U chamber, and FIGS. S. U. The results of the chamber test are shown, and FIGS. 5 and 6 show the results for Example 6. Procedural amendment/Relationship with 11 cases > 1 qr - Intake 7' i Most recent 5, Procedural amendment subject to amendment 0) Tadashi 4゜agent

Claims (1)

[Claims] 1. Thermosetting resins, especially polyimide, phenol, epoxy, silicone or bismaleimide-based resins, or thermoplastic resins, especially polyester-imide (PEI), polyester-sulfone (PES) or polyester- Complies with ATS Standard 10000-001 and Directive FAS 25 (O.S.U. Chamber) based on mica paper impregnated with 5-40% of ketone resin or binder-free, especially silicate or phosphate binder. Thank you,
A structural element provided with a fireproof coating that has weak heat generation properties. 2. Claim 1, wherein the mica paper is impregnated with a thermosetting or thermoplastic resin or an inorganic binder at a ratio of 10 to 15%.
The structural element described. 3. Structural element according to claim 1, wherein the coating consists of mica paper impregnated with silicone resin in a proportion of 5 to 40%, preferably 10 to 15%. 4. Any one of claims 1 to 3, wherein the coating comprises impregnated mica paper adhesively bonded to a support such as a woven or non-woven glass, aramid, carbon or other fiber based support. structural elements. 5. A structural element according to any one of claims 1 to 4, wherein the mica consists essentially of phlogopite. 6. Woven or non-woven glass, aramid, carbon or 5-40%, preferably 10-15% of a thermoset, thermoplastic or inorganic binder adhesively bonded to another fiber-based support
mica paper impregnated with %. 7. Thermosetting resin, thermoplastic resin or silicate-based inorganic binder, preferably silicone resin, 5-40%
ATS Standard 100, consisting of a sheet or tape of mica paper impregnated with , preferably at a rate of 10-15%.
00-001 and Directive FAR 25 (O.S.U. Chamber), fire protection coating with low heat generation properties. 8. Adhesively bonded to a mica paper sheet or tape by suitable adhesives known per se, by a woven or non-woven glass, aramid, carbon or other fibre-based support. 8. The coating of claim 7, wherein the coating is supported. 9, ATS10000-001 and command FAR25(O
．． S. U. Application of silicone resins as a binder for mica laminates intended for fire protection of structural elements that conform to the chamber) and have a weak heat generation.