Note : Les descriptions sont présentées dans la langue officielle dans laquelle elles ont été soumises.
A TH~RMOPLASTIC MATERIAL FOR SOUNDPROOFING AND VIBRATI0~ 7SULA~ING
APPLICAT~ONS, AND LAMINATED A~D STP~TIFIED PRODUCTS OBTAINED FROM IT,
PARTICULARLY FOR MOTOR VEHICLES.
scoPe of the invention
The object of the present invention is thermoplastic materials and
laminated and stratified products obtained therefrom, which have
soundproofing and vibration insulating properties and which can be used,
in particular, in the partition between the engine and the interior of a
motor vehicle, such as a saloon car, and, in general, in other locations
in cars, train~, aircraft, etc., and in wall~, floors, ceilings, and
metal claddings of buildings and in domestic appliances and industrial
machines ~in the latter two cases, for its vibration insulating
properties).
Previous technolo~y
The present applicant is the holder of Spanish patent number
554,644 for a "Procedure for obtaining a laminable thermoplastic
material and a laminate obtained with this material" and of
corresponding patents and patent applications submitted in all advanced
industrialised countries, such as the United States of Americaj Great
Britain, the Federal Republic of Germany, France, Japan, etc.
The said Spanish patent protects the exclusive right to produce a
thermoplastic material which comprises chloropolyethylene, mixed with an
oil, which can be replaced by a plasticizer, and fillers. The
descriptions of these patents and those of the patents of the previous
technology mentioned therein, are included here for reference.
Description of the obiect of the present invention
A thermoplastic material, and the laminated and stratified products
obtained therefrom, suitable for the aforementioned applications, and
particularly for the partition between the engine and the interior of a
motor vehicle, must possess:
- excellent acoustic characteristics (acoustic barrier and anti-
vibration);
- good values of the property known as "fogging~ ~which is the shedding
of volatile materials which are depo~ited on cold surfaces,
particularIy glass surfaces such a5 the windowa of the interior of
the vehicle, obstructing visibility through them);
- high flexibility;
- the capability of being easily fitted to other components and to the
: ,
'~ ~ ' ` ` ` `
.
3 ~
wall3 of the vehicle interior or compartment;
- high stability and resistance at extreme temperatures;
- optimum valuea of Young's modulus, that i8 to say the elastic modulus
under compression, and of the mechanical 10s9 factor ~known a3 the
~Delta~ tangent, which measureq the energy dissipating characteri~tics
of the material);
- good ageing and adhesion properties;
- the capability of being easily laminated, processed and handled; and
- the capability of being manufactured economically.
Descri~tion of the invention
The applicant, on investigating the material and the products
obtained therefrom, of the aforementioned Spanish patent numb~er 554,644,
~ound that the eatablished objective can be achieved by replacing the
oil or plasticizer of said patent 554,644 by an extender selected from
one or more of the following materials: plasticizers with a low
volatility, hydrocarbonated oils, asphalt and/or other materials which
perform the same function as an extender, provided that the overall
compatibility between the extender and the chloropolyethylene is
maintained, this compatibility being defined by an annealing point
which, measured accordin~ to AST~ T-611, method B, must be less than
100C, and preferably less than 70C.
Consequently, the thermoplastic material is comprised of between
25 0.6 and 50~ of chloropolyethylene; between 20 and 95~ of filler; and
between 4 and 60~ of the aforementioned extender; the material,
furthermore, contains minor constituents in order to adapt the physical
properties, of the material as a whole as well as some of it~
constituents, to the desired objective; in particular, "fogging"
30 (qhedding of volatile materials), measured according to standard 75201,
is optimum.
This thermoplastic material is laminated, by itself or together
with an absorbent material located in any position and/or in one or more
layers, to give a laminated or stratified product which is then placed
in the desired location.
Also, the material can be laminated by itself and then sent in that
condi~ion to another factory, where it is joined to absorbent materials
such as porous felt, synthetic foams, wood, cork, etc., to obtain
stratified products which are then placed in the desired locations.
The extender constituent must be selected as appropriate for each
particular case, but the annealing point must alwaya be le~a than 100C.
.
.
:: ~
: . . '~:
.: ~
2~4~
Test methods used to measure the properties
a) Fogging, that is to say the shedding of volatile materials from
the material and the 3ubsequent condensation thereof on cold surfaces,
especially glass surfaces, and in particular on the windows of the
vehicle, expreqsed as the quantity of these volatile materials d2posited
on the ~urfaces, must be as small as possible. Furthermore, the
deposits produced by these volatile mater-als must have a very low
opacity 90 that they do not obscure visibility through the glass, in
particular, through the front windscreen of the vehicle. This property
is measured by mean3 of DIN 75201, although SAAB SCANIA STD 1082 or FORD
LABORATORY TEST MET~OD EUBN 1-1 can also bs used.
b) The flexibility of the material is measured by static
deflection, which is defined as the deflection occurring in a~test piece
under its own weight when placed partly on and partly overhanging a
ta~le. It has been observed experimentally that sheets made from very
flexible materials are ~etter barriers to sound than sheets made from
rigid materials.
c) Behaviour in low temperatures i8 expressed by the brittleness of
the material~ o~tained. This i~ measured by allowing a 500 g steel
ball to fall from a height of 30 cm, and observing if, at the low
temperature of the test, cracks appear in the material.
d) ~esi~tance and stability to high temperatures is measured by
placing the material on a slope of 75 for 5 hours at a temperature of
85C, and then observing if the material flows or not.
It has been observed that the product~ obtained in accordance with
the invention do not undergo any alteration or modification.
e) ~oung's modulus, that is to say the elastic modulus under
compres~ion, is measured with an instrument called a Metravib under a
displacement of + 50.um. The Delta tangent, or tg S , represents the
mechanical loss factor and expresses the dissipative characteristics of
the material. It is measured in relation with the measurement of
~oung's modulus. The lower the value of modulus E' ~that is to say
the real part of Young's modulus) the greater the elasticity of the
material, and the greater the value of tg ~ the more dissipative it is.
Examples of realisation
Some thermoplastic materials were prepared and numbered 1 to 5, the
material of example 1 corresponding to a typical material prepared
accordinq to Spanish patent 554,6~,q" and the materials of examples of 2
to 5 in accordance ~ith the invention.
From these material5 measurements were made, according to the test
methods mentioned above, of the annealing point, fogging and
-- 3
.
. .
2 ~ 3 ~
brittleness .
Next, a table was produced of the compo~ition of the tnaterials of
the various examples and the values of th~ afortementioned
characteristics were measured.
In these tables, (1) designates the product Repex E-7 ~rom the firm
REPSOL DERIVADOS; ( 2 ) designates the product SMR-60 from the firm REPSOL
DERIVADOS; and (3) designates the plaaticizer DIDP (abbreviation for
di-isodecyl phthalate).
10 EXAMPLES 1 2 3 4 5
Ouantities of in~redients (parta/weiaht)
Aromatic oil (1) 850 ~25
15 Semi-aromatic oil (2) 850 425
Plasticizer (3) 425 425 850
Filler 4500 4000 4500 4500 4500
Chloropolyethylene 225 200 225 225 200
20 PHYSICAL CH~RACTERISTICS
Annealing point (C) 102 63 20 60 20
Fogging incompatible 96 97 87
Brittleness ~C) -5 -25 -30 -30
With the materials of examples 2 to 5 and with a sample product
already known on the market, based on asphalt plus an EPDM polymer
(abbreviation for ethylene-propylene-diene monomer), measuremen~s were
taken of the sound insulation in the form of the level of soundproofing,
expressed in decibels, at various sound frequencies. These measurements
were carried out using a booth consisting of two small chambers with
identical anechoic characteristics, separated by a metal plate. In one
of the chambers there is a loudspeaker and in the other a microphone by
which the sound pressure level is measured.
Firstly, the sound pressure level is measured with the 0.8 mm steel
plate in place, and then with the chambers separated by the complex
formed by the steel plate, the absorbent (19 mm thick porous felt) and a
7 kg/m sheet obtained according to the invention. The difference,
expressed in decibels, constitutes a measurement of the sound insulation
of the complex formed by the absorbent material and the soundproofing
material tested.
~ - , :
.
C~ 3 ~
Examples Sample Soundproofing level
2 3 g 5
FREQUENCIES decibels
Hz125 10 15 14 14 14
250 6 7 8 8 7
500 14 16 16 16 16
1000 16 19 l9 l9 18
2000 36 37 39 39 39
4000 37 43 gl 42 40
8000 49 50 52 51 51
15 From this table it ia concluded that the soundproofing lèvel of the
sample material is lower than that of examples 2 to 5.
The preqent invention has been described above, particularly as
represented by ~ome preferred examples. However, the scope of the
invention covera all variants falling under the following claims.
.
~ - : .; " . : . ~ :
