WO2009040374A2

WO2009040374A2 - Eps foam board having a reflective surface

Info

Publication number: WO2009040374A2
Application number: PCT/EP2008/062770
Authority: WO
Inventors: Matthias Hofbauer
Original assignee: Wki Isoliertechnik Gmbh
Priority date: 2007-09-24
Filing date: 2008-09-24
Publication date: 2009-04-02
Also published as: EP2203611A2; WO2009040374A3; DE202007013369U1

Abstract

The invention relates to an EPS foam board (1) made of coated styropolymer spherules (4) and a method for producing an EPS foam board (1) made of coated styropolymer spherules. According to the invention, partially hollow-body shaped reflectors (3) are formed on at least one surface (2) of the EPS foam board (1), and a block body made of EPS foam is separated into individual EPS foam boards (1) of a thickness that is prescribed or can be prescribed.

Description

EPS foam board with reflective surface

description

The invention relates to an EPS foam sheet of styrene polymer beads with a reflective coating, a process for producing an EPS foam sheet, an EPS foam sheet system and a use with the features mentioned in the preambles of independent claims.

EPS foam boards are widely used for thermal insulation of facades. For these façade panels, the lowest possible N value according to DIN 52612 is important. In order to obtain a λ value according to DIN 52612 with or below 35 mW / mK, extensive developments have been made primarily using so-called athermal additives for the styrene polymer, such as carbon black, graphite, aluminum and other suitable materials, and corresponding expandable styrene polymer materials for the EPS Foam panels offered in the market. A striking feature of all these materials is a continuous light to dark gray colored EPS foam board. Likewise, EPS foam boards made of styrene polymer are on the market, which are provided with a mixture of normal and athermal additives, so-called Dalmatiner plates.

The EPS foam plates with reduced thermal conductivity and their materials are described for example in EP 778 309, EP 863 175, EP 915 127, EP 981 574, DE 10 2004 028 768 and EP 1 159 338. All inventions have in common that atherme materials are used to reduce the thermal conductivity of the styrene polymer in conjunction with other substances to increase the flame resistance for an improved fire class of EPS foam boards.

As a disadvantage of the EPS facade panels, consisting of the EPS styrene polymer beads equipped with athermal materials, the deformation of the panels has been found in strong thermal solar radiation. With a newly marketed EPS styrene polymer with the registered trademark Slimpor, which is also intended for EPS foam boards with reduced thermal conductivity, was due to its only external cladding of the EPS beads with an aluminum substrate and with the performed after foaming mechanical processing found that these EPS foam boards have a λ value below that of the white or otherwise colored EPS, although the interior of the EPS beads has the white or otherwise colored styrene polymer. The Korean document KR 102007076026 describes, for example, an EPS styrene polymer beads coated with microfine aluminum disks and used for producing EPS foam boards.

What applies to the facades is even more important for roof insulation panels, as the sun's rays often strike at a 90 ° angle and thus act on the insulated roof from several KW of power / m2 in the summer.

The object of the invention is to improve the heat-insulating properties of the EPS foam sheets of coated EPS styrene polymer beads, in particular with regard to the infrared radiation and / or the visible solar radiation. Another object of the invention is to prevent the heating of the EPS foam sheets by incident radiation, to reduce their thermal conductivity, and to deform as a result of the different expansion caused by solar radiation.

The objects according to the invention are achieved in that partial hollow-body-shaped reflectors are formed on at least one surface of the EPS foam sheet in the case of an EPS foam sheet consisting of coated polystyrene beads.

It is advantageous if the partially hollow-body-shaped reflectors are filled with polystyrene, because they are then produced simply by cutting the surface. In this case, the infrared radiation passes through the styrofoam polymer to the reflective coating, where it is reflected.

It is of a particular further advantage if this surface is formed from separated polystyrene beads. The reflective coating of the styrofoam polymer beads is preferably a coating designed for the reflection of the infrared radiation and / or the visible solar radiation and, in further advantageous embodiments, for example formed from one of the materials carbon black, graphite or aluminum. This effect further has the effect that the trimmed EPS styrene polymer beads with their outer aluminum cladding act as a reflector for the incident heat radiation of the sun on facades. This has, as proven in experiments, with the result that these cladding panels heat less in intense sunlight than the previously made of an athermal EPS styrene polymer facade panels.

According to a process engineering aspect of the present invention, this is based on a process for producing an EPS foam sheet from coated styrofoam polymer beads, comprising steps for foaming previously, preferably reflective, coated styrofoam bead to form a block body.

The fact that this block body is separated into a plurality of EPS foam plates of predetermined or predeterminable thickness, the objects of the present invention are procedurally solved. Here, the effectiveness of the inventive surfaces of the EPS foam sheets is particularly high when the cutting plane is selected such that the cut through them Styropolymerisatkügelchen are divided substantially centrally. The thus divided Styropolymerisatkügelchen thus form the most favorable geometric configuration of the part-hollow body-shaped reflectors from separated Styropolymerisatkügelchen. The reflection of the incident radiation can therefore be done more effectively, which can be confirmed in a surprising manner by measurement results.

The block body is preferably rectangular, rhombus-shaped, trapezoidal or polygonal shaped. In this case, the separation of the block body into a plurality of EPS foam sheets can be carried out preferably by cutting and / or fusion cutting / melt cutting, each EPS foam sheet (1) receives a front and a back plate surface.

Because can be achieved by the inventively embodied surface of the EPS foam board a significant increase in thermal insulation properties, several successively arranged according to the invention EPS foam plates can be used to further increase heat insulating properties. According to a preferred embodiment of the method according to the invention at least two EPS foam sheets are joined together at their front and rear plate surfaces. It is particularly advantageous if the connection between at least two EPS foam boards is made using an adhesive.

According to a further aspect of the invention, the present invention is based on an EPS foam sheet system of a plurality of stacked EPS foam sheets.

Characterized in that at least two EPS foam sheets are joined together according to one of the preferred embodiments described above at their front and rear plate surfaces, wherein the respective formed by the part-hollow-shaped reflectors surfaces of each EPS foam sheet are aligned in the same direction, the objects solved this invention systemically.

The connection between at least two EPS foam sheets is preferably carried out in a preferred embodiment of the EPS foam sheet system according to the invention using an adhesive.

According to another aspect of the present invention, the objects of the invention are achieved by using an EPS foam board produced by the method of any of the above-described preferred embodiments and / or an EPS foam board system for thermal insulation of facades made according to one of the described embodiments and / or roofs of buildings solved.

The EPS foam sheet and / or EPS foam sheet system is preferably arranged on the building surfaces such that the surfaces formed by part-hollow-shaped reflectors surfaces of the EPS foam sheets are directed to the outside.

In practical use of the facade insulation panels and the roof insulation panels, it is also advantageous if the facades are provided with a heat-reflecting plaster layer or paint and the roof insulation panels with a heat-reflecting roof skin.

Further preferred embodiments of the invention will become apparent from the remaining, mentioned in the dependent claims characteristics. The invention will be explained below in embodiments with reference to the accompanying drawings. Show it:

Figure 1 is a perspective view of an embodiment of the invention

EPS foam sheet;

Figure 2 is a schematic cross-sectional and partial sectional view of an embodiment of the EPS foam sheet system according to the invention;

Figure 3 is an enlarged schematic cross-sectional and partial sectional view of a

Embodiment of the EPS foam sheet according to the invention;

Figure 4 is an enlarged schematic partial top sectional view of a

Embodiment of the EPS foam sheet according to the invention; and

Figure 5 is a further enlarged schematic cross-sectional and partial sectional view of a conventional EPS foam sheet.

FIG. 1 shows a perspective view of an embodiment of the EPS foam board 1 according to the invention. The frontally represented surface 2 of the EPS foam board 1 has a surface structure typical for EPS foam boards. This structure results from the fact that the polystyrene beads 4, which make up the EPS foam, were foamed in a sintering process. The individual Styropolymerisatkügelchen 4, are brought to the expansion of the hot, for example, by a 140 ⁰ C vapor pressures so tightly together that they will be deformed to irregular shaped bodies, which together form visible transition surfaces. Since the polystyrene beads for the present EPS foam sheet 1 have, for example, aluminum coating with an aluminum powder, the separating surface formed between the adjacent sintered polystyrene beads 4 is formed of this aluminum layer.

The EPS foam sheets 1 of the invention are preferably made by separating thinner sheets from a larger block body. The separation can be done by cutting tools or melt separation tools. Here, in a particularly preferred embodiment of the present invention, the parting plane between the individual plates is selected such that the Styrolpolymerisatkügelchen 4 are cut as centrally as possible. As a result, part-hollow-body-shaped reflectors 3, which are divided into half shells, form on the surface 2 of the EPS foam board 1. The surface 2 of the EPS foam sheet 1 is characterized by a surface formed of uncoated EPS foam, which is covered by a fine network of substantially perpendicular to the surface 2 arranged separating surfaces 7, which separate the individual cut part-hollow body-shaped reflectors 3 from each other. The partially hollow-body-shaped reflectors 3 thus form, according to the invention, inwardly curved, ie concave, mirrored aluminum reflecting surfaces or reflectors whose geometric shape is particularly advantageous for impinging on the surface 2 of the EPS foam board 1 infrared or visible To reflect solar radiation.

Surprisingly, measuring experiments have shown that the surface 2 of the EPS foam board 1 formed in accordance with the invention reflects the heat, ie the infrared radiation, much more effectively than a conventional EPS foam sheet of aluminum-coated styrene polymer beads.

FIGS. 3, 4 and 5 are followed by an explanation of physical relationships to this result according to the invention.

FIG. 2 shows a schematic cross-sectional and partial sectional view of an embodiment of the EPS foam board system 6 according to the invention.

Because the inventively designed surface 2 of an EPS foam sheet 1, as shown in Figure 1, causes a much more effective reflection of the infrared radiation and the visible solar radiation, in the present embodiment of the present invention, several EPS foam sheets 1 produced according to the invention superimposed and, for example with a Adhesive bond to an EPS foam board system 6 united.

It is particularly advantageous in this case to align all or several of the individual EPS foam sheets 1 k with their respective surface 2 k in a direction from which the radiation to be reflected is to be expected. As a result, the remaining infrared radiation, which has passed a reflection surface 2k located in front of it, will encounter a next reflection barrier. Preferably, EPS foam board systems 6 produced in accordance with the invention are preferably arranged on the outer surfaces or roof surfaces of buildings in such a way that the reflection surfaces 2k are aligned outwardly against the infrared and / or solar radiation.

Hereby, according to the invention, a particularly effective thermal insulation protection, in particular for buildings, can be realized. Further applications are conceivable in vehicle construction.

FIG. 3 shows an enlarged schematic cross-sectional and partial sectional view of an embodiment of the EPS foam board 1 according to the invention.

Based on this representation, the physical background of the present invention is particularly accessible explained. The part-hollow-body-shaped reflectors 3, which are shown in a lateral cross-section and can be recognized as half-shells, essentially form half-shell-shaped, mirrored, concave reflectors. Each of these cup-shaped reflectors 3 is, as described above, provided with a reflective, for example aluminum, coating and formed by the separating surfaces 7.

On the one hand, as can be seen, the surface of the reflectors 3 formed in this way is not entirely regular since it is produced by a sintering process in which the expanding styrene polymerate beads exert pressure against each other. This irregular surface formation deteriorates the reflection properties of the reflectors 3. Furthermore, this surface is also not particularly smooth, so that in addition the roughness of the parting surface 7 deteriorates the reflection properties. Finally, the material of the coating, for example aluminum powdering or coating with graphite powder, likewise forms the reflection properties of these reflection surfaces 7. The consequence of this deteriorated reflection properties is that those rays which have a particularly blunt impact angle on a partial area of a separating surface 7 are reflected less well , This is true for the rays which reach the reflectors 3 essentially in the center and the absorption area marked with the brace 2.

A radiation component of the incident radiation A, which arrives on the respective reflectors 3 via the outer regions or areas of the surface 2 marked as reflection regions I, has good reflection conditions. The beam path of this radiation is represented by arrows labeled Aa as an outer beam path. Because this part of the radiation impinges on the separation surface 7 at a shallow angle, its rays are much better reflected and redirected to the next, again at a shallow angle incident beam path. Thus, an outer ray Aa can be most effective along the dividing surface 7 of a respective reflector 3 are reflected several times and thrown back outwards.

This physical phenomenon of high reflection at a flat angle of incidence is known: for example, the intrinsically black and non-reflective surfaces of paved roads turn at high heat and, for a distant look, into mirror surfaces apparently resembling a water surface. This effect can only be determined at a very shallow angle, because if one goes to the apparent location of the reflection, then no reflection is detectable there, because the radiation angle is then no longer flat enough.

Thus, it is ensured by the partial hollow-body-shaped reflectors 3 according to the invention that the incident radiation is reflected very well in the outer reflection regions I, while in the inner absorption region II the incident radiation absorbs more or predominantly and thus passes into a nearest styrene polymer beads 5. As can be seen from the illustration, however, the ratio of the outer reflection regions I to the inner absorption region II is approximately such that about 30 to 40% is attributable to the absorption region II, and the remaining 60 to 70% is attributable to the reflection region I. In addition, since the reflectors 3 are not two- but three-dimensional objects, this ratio of 3: 7 or of 4: 6 has a square effect when converting to a surface.

For this purpose, it is useful to consider a plan view of a reflector 3, which is shown in the next figure 4.

Figure 4 shows an enlarged schematic plan view of a partial section of a preferred embodiment of the EPS foam sheet 1 according to the invention.

Only in an idealizing way, the outer contour of the reflector 3 is shown in a circle. However, the following conclusions are likely to apply with sufficient accuracy to the rather irregular contours of the reflectors 3. As can be seen, the internal absorption region II is denoted by a curly bracket Il corresponding to the diameter d, approximately one third of the outside diameter Da of the reflector 3. This shows that the surfaces of the outer reflection region I of the reflector 3 and the surface of the internal absorption region II must be in relation to each other in order to find out what proportion of the incident radiation is effectively reflected and which is absorbed. If one assumes, as previously described, that the diameters d, and Da have a ratio of 4: 6 and 3: 7 respectively, the following effect on the area ratio results:

For the internal absorption area Il applies:

π-d,

F, =

And for the reflection area I:

π - D

F "= - F.

Related to each other, it results in:

^'

After shortening, the area ratio results for:

In this formula, it can be seen that the two diameters Da and d are each related to each other quadratically. This means, for example, assuming the ratio 3: 7, 3 squared 9 and 7 squared 49, so that the ratio is 9:49. This makes it clear from where the large effectiveness of the invention surface

2 of the EPS foam sheet 1 comes from. This calculation example states that only 20% of the incident rays can not be reflected, while 80% are reflected very effectively.

FIG. 5 shows a comparison of the physical processes for a conventional EPS foam board or, for the inner styrene polymer beads 5, corresponding optical paths for the illustration in FIG.

In this case, a radiation coming from direction A strikes a curved, reflecting surface of an inner styrene polymer bead 5. In the same way as in FIG. 4, the surface can be subdivided into regions of favorable reflection angles and a central region with unfavorable radiation incidence angles, an absorption region III and a reflection region IV.

For the central absorption region III, what has been said above also applies, d. That is, the radiation incident here impinges at an obtuse angle from a 90 ° near angle on the reflective surface of the inner styrene polymer bead 5 and penetrates it due to the poor reflection properties. The radiation A incident in the outer reflection regions IV is, as described above, reflected well and effectively thanks to the flat angles of incidence. As can be seen from the beam path, an outer beam path Aa is hereby deflected to the adjacent Styrolpolymerisatkügelchen, where it now impinges at an obtuse, almost 90 ° angle. As a result, this radiation passes through the reflective separation surface of the adjacent Styrolpolymerisatkugelchens, d. H. The radiation is absorbed and reaches the interior of the EPS foam.

Since the geometric relationships are the same as described above under FIGS. 3 and 4, this even leads to the absorption rate now being 20:80% or worse.

It should also be noted that the processes for beam paths in FIGS. 4 and 5 also apply if the radiation A strikes at an oblique angle because the reflectors

3 have approximately a spherical shape. LIST OF REFERENCE NUMBERS

1 EPS foam board

1 k k-th EPS foam board

2 surface

2k k-th surface

3 part-hollow body reflectors

4 polystyrene beads, external

5 internal styrofoam polymer beads

6 EPS foam board system A Beam direction

Aa outer beam path

Ai inner beam path

Di diameter, inner

Because outer diameter,

Fa reflection area

Fi absorption area

I, IV reflection area

II, III absorption range

Claims

claims

1. EPS foam sheet (1) consisting of coated Styropolymerisatkügelchen (4), characterized in that on at least one surface (2) of the EPS foam sheet (1) partially hollow body-shaped reflectors (3) are arranged.

2. EPS foam board (1) according to claim 1, characterized in that the partially-hollow body-shaped reflectors (3) are filled with polystyrene.

3. EPS foam sheet (1) according to any one of the preceding claims, characterized in that the surface (2) is formed from separated Styropolymerisatkügelchen.

4. EPS foam sheet (1) according to any one of the preceding claims, characterized in that the reflective coating of Styropolymerisatkügelchen (5) is designed for the reflection of the infrared radiation and / or the visible solar radiation coating.

5. EPS foam sheet (1) according to claim 4, characterized in that the coating of Styropolymerisatkügelchen is formed from one of the materials carbon black, graphite or aluminum.

6. A method for producing an EPS foam sheet (1) from coated Styropolymerisatkügelchen (5), comprising steps for foaming previously coated Styropolymerisatkügelchen () into a block body, characterized in that the block body in a plurality of EPS foam plates (1) predetermined or predetermined thickness is separated.

7. The method according to claim 6, characterized in that the cutting plane is selected such that the Styropolymerisatkügelchen cut through them (5) are divided substantially centrally.

8. The method according to any one of the preceding claims, characterized in that the block body is rectangular, rhombic, trapezoidal or polygonal shaped.

9. The method according to any one of the preceding claims, characterized in that the separation of the block body in a plurality of EPS foam sheets (1) by cutting and / or fusion cutting / melt cutting is performed, each EPS foam sheet (1) has a front and a receives back plate surface.

10. The method according to any one of the preceding claims, characterized in that at least two EPS foam plates (1, 1) are connected to each other at their front and rear plate surfaces.

1 1. A method according to claim 10, characterized in that the connection between at least two EPS foam plates (1, 1) is carried out using an adhesive.

12. EPS foam sheet system (6) of a plurality of stacked EPS foam sheets (1 k), characterized in that at least two EPS foam sheets (I ₁ , 1 ₂ ) according to one of claims 1 to 5 at its front and rear plate surfaces are interconnected, wherein the respective formed by the part-hollow body-shaped reflectors (3) surfaces (2) of each EPS foam sheet (1, 1) are aligned in the same direction.

13. EPS foam board system according to claim 12, characterized in that the connection between at least two EPS foam plates (1, 1) is carried out using an adhesive.

14. Use of an EPS foam board (1) produced by the method according to one of the preceding claims 6 to 11 and / or of an EPS foam board system (6) produced according to one of claims 12 to 13 for a thermal insulation of facades and / or roofs of buildings.

15. EPS foam plates with reduced thermal conductivity through the use of expandable styrene polymer beads with outer IR-reflective athermal coatings, characterized in that in these after their mechanical processing on the outer surfaces of the EPS foam plates substantially only the styrene polymer is visible and with the cut styrene polymer beads the inner coated side of the beads is a reflector for the incident heat radiation and both together causes a reduction in the heating of the EPS foam sheets by sunlight.

16. EPS foam plates with reduced thermal conductivity through the use of expandable styrene polymer beads with outer IR-reflective athermal coatings according to claim 1, characterized in that these EPS foam boards are used due to their low thermal conductivity and reflection of thermal radiation as Fassadendämmplatten and roof insulation panels ,

17. EPS foam plates with reduced thermal conductivity by the use of expandable styrene polymer beads with outer IR-reflective athermal coatings according to claim 1 and 2, characterized in that the use as facade panels in conjunction with an outer heat-reflecting plaster and color coating to a much lower Thermal stress on the facades in summer leads.

18. EPS foam boards with reduced thermal conductivity through the use of expandable styrene polymer beads with outer IR-reflective athermal coatings according to claim 1 and 2, characterized in that the use as a roof insulation panels in conjunction with a heat-reflecting outer roof skin to a much lower thermal load on the roof in the Summer leads.