Compressible structural panel

Abstract

A structural panel for use in building structures or in the formation, finish or decoration thereof includes an outer sheet and a connector sheet with a plurality of collapsible or compressible dividers therebetween. The panel in a rest condition is expanded and of a desired thickness for final use but can be compressed into a relatively thin thickness or profile for shipping purposes. The panel is very lightweight but structurally strong and can be selectively bent in one transverse direction if desired. The panel can be easily cut or formed into any predetermined size or shape.

1 . A compressible structural panel comprising in combination: 
 at least one outer sheet of material having an inner and outer face, and    at least one compressible divider that in a resting condition is expanded and secured to and protrudes from said inner face, said divider being compressible.    
     
     
         2 . The panel of  claim 1  wherein there are a plurality of dividers and further including connector means for securing said dividers together at locations distal from said outer sheet.  
     
     
         3 . The panel of  claim 1  or  2  wherein said at least one divider or dividers are elongated and extend in parallel relationship to each other.  
     
     
         4 . The panel of  claim 1  or  2  wherein said at least one divider or dividers are made of a semi-rigid material.  
     
     
         5 . The panel of  claim 3  wherein there are a plurality of dividers that are independent of each other.  
     
     
         6 . The panel of  claim 4  wherein there are a plurality of said dividers are independent of each other.  
     
     
         7 . The panel of  claim 4  wherein there are a plurality of said dividers that are foldable into said compressed condition.  
     
     
         8 . The panel of  claim 6  wherein said dividers are foldable into said compressed condition.  
     
     
         9 . The panel of  claim 8  wherein said dividers are biased toward the resting condition.  
     
     
         10 . The panel of  claim 2  wherein said dividers are made from independent sheets of a semi-rigid but foldable material, said independent sheets being folded such as to define flaps that are securable to said outer sheet and said connector means and a pair of partitions extending between said flaps, said partitions being collapsible.  
     
     
         11 . The panel of  claim 10  wherein said partitions are substantially elongated and planar and said dividers have a longitudinally extending fold between said flaps and said partitions which allow the partitions to be folded into substantially face-to-face relationship with said flaps when in the compressed condition.  
     
     
         12 . The panel of  claim 10  wherein said independent sheets are made of fiberglass including a plurality of glass fibers bonded together with a resin.  
     
     
         13 . The panel of  claim 12  wherein said resin is a thermoses resin.  
     
     
         14 . The panel of  claim 12  wherein said resin is thermoplastic.  
     
     
         15 . The panel of  claim 12  wherein said resin is a combination of a thermoset and a thermoplastic resin.  
     
     
         16 . The panel of  claim 12  wherein said outer sheet is fiberglass including a plurality of glass fibers bonded together with resin.  
     
     
         17 . The panel of  claim 16  wherein said resin in the outer sheet is a combination of thermoset and thermoplastic resin.  
     
     
         18 . The panel of  claim 16  wherein said resin the outer sheet is a thermoset resin  
     
     
         19 . The panel of  claim 16  wherein said resin the outer sheet is a thermoplastic resin.  
     
     
         20 . The panel of  claim 16  wherein said connector means is a sheet of material.  
     
     
         21 . The panel of  claim 20  wherein said connector means is a fiberglass sheet.  
     
     
         22 . The panel of  claim 20  wherein said connector means includes a plurality of glass fibers bonded together with resin.  
     
     
         23 . The panel of  claim 22  wherein said resin in the connector means is a thermoset resin.  
     
     
         24 . The panel of  claim 22  wherein said resin in the connector means is a thermoplastic resin.  
     
     
         25 . The panel of  claim 22  wherein said resin in the connector means is a combination of thermoset and thermoplastic resins.  
     
     
         26 . The panel of  claim 12  wherein said outer sheet also includes a plurality of glass fibers bonded together in a resin.  
     
     
         27 . The panel of  claim 26  wherein said resin is a thermoset resin.  
     
     
         28 . The panel of  claim 26  wherein said resin is a thermoplastic resin.  
     
     
         29 . The panel of  claim 26  wherein said resin is a combination of thermoset and thermoplastic resins.  
     
     
         30 . The panel of  claim 12  wherein said connector means is a sheet of fiberglass including a plurality of glass fibers bonded together in a resin.  
     
     
         31 . The panel of  claim 30  wherein said resin is a thermoset resin.  
     
     
         32 . The panel of  claim 30  wherein said resin is a thermoplastic resin.  
     
     
         33 . The panel of  claim 30  wherein said resin is a combination of thermoset and a thermoplastic resin.  
     
     
         34 . The panel of  claim 16  wherein said connector means includes a plurality of flexible but non-extensible strands connected to said dividers.  
     
     
         35 . The panel of  claim 1 ,  2  or  10  wherein said panel is a ceiling panel.  
     
     
         36 . The panel of  claim 10  wherein said partitions each include a longitudinal fold so as to define a pair of partition portions.  
     
     
         37 . The panel of  claim 36  wherein said panel portions are of the same size.  
     
     
         38 . The panel of  claim 36  wherein said panel portions are of different sizes.  
     
     
         39 . The panel of  claim 1  or  2  further including a decorative sheet secured to the outer face of said outer sheet.  
     
     
         40 . The panel of  claim 2  wherein said connector means includes a plurality of flexible but non-extensible strands connected to said dividers.  
     
     
         41 . The panel of  claim 40  wherein said dividers have an upper surface and a lower surface and wherein said lower surface of said dividers is secured to said outer sheet and said upper surface to said non-extensible strands.  
     
     
         42 . The panel of  claim 2  wherein said dividers have an upper surface and a lower surface and wherein said lower surface of said dividers is secured to said outer sheet and said upper surface to said connector means.  
     
     
         43 . The panel of  claim 2  wherein said connector means is an inner sheet of material.  
     
     
         44 . The panel of  claim 43  wherein said inner sheet consists of a plurality of strips of material.  
     
     
         45 . The panel of  claim 43  wherein said outer sheet consists of a plurality of strips of material.  
     
     
         46 . The panel of  claim 44  wherein said outer sheet consists of a plurality of strips of material.  
     
     
         47 . The panel of  claim 44  or  45  wherein said strips on at least one of said inner and outer sheets are interconnected.  
     
     
         48 . The panel of  claim 47  wherein said strips on both said inner and outer sheet are interconnected.  
     
     
         49 . The panel of  claim 43  wherein said inner sheet is integral with said dividers.  
     
     
         50 . The panel of  claim 1  or  2  wherein said outer sheet is integral with said at least one divider or dividers.  
     
     
         51 . The panel of  claim 49  wherein said inner and outer sheets are integral with said dividers.  
     
     
         52 . The panel of  claim 1  or  2  wherein said at least one divider or dividers are made from fiber glass matting.  
     
     
         53 . The panel of  claim 52  wherein said fiber glass matting is composed of a glass fiber matrix bonded with a fire retardant melamine resin composition.  
     
     
         54 . The panel of  claim 53  wherein said matting has at least 27% by weight nitrogen in the dry, but uncured state of the melamine resin.  
     
     
         55 . The panel of  claim 53  wherein the glass fibers in the matrix have diameters in the range of 3 to 20 microns.  
     
     
         56 . The panel of  claim 53  wherein said glass fibers are about the same length.  
     
     
         57 . The panel of  claim 55  wherein said glass fibers are about the same length.  
     
     
         58 . The panel of  claim 56  wherein the length of said fibers is approximately 0.75±0.08 inch.  
     
     
         59 . The panel of  claim 57  wherein the length of said fibers is approximately 0.75±0.08 inch.  
     
     
         60 . The panel of  claim 53  wherein said glass fibers are shorter than 3 inches.  
     
     
         61 . The panel of  claim 55  wherein said glass fibers are shorter than 3 inches.  
     
     
         62 . The panel of  claim 53  wherein said melamine resin has at least 35% by weight nitrogen.  
     
     
         63 . The panel of  claim 53  wherein said melamine resin is 5-50% by weight of the finished matting, the glass fibers are 10-95% by weight of the finished matting and further including organic fibers constituting 0-50% by weight of the finished matting.  
     
     
         64 . The panel of  claim 63  wherein said organic fibers come from the group consisting of thermoplastic or thermoset polymers.  
     
     
         65 . The panel of  claim 63  wherein said organic fibers come from the group of natural fibers including wood, cotton and cellulose derivatives such as rayon or acetate fibers.  
     
     
         66 . The panel of  claim 1  or  2  wherein said outer sheet is made of fiberglass matting.  
     
     
         67 . The panel of  claim 43  wherein said outer sheet is made of fiberglass matting.  
     
     
         68 . The panel of  claim 67  wherein said fiber glass matting is composed of a glass fiber matrix bonded with a fire retardant melamine resin composition.  
     
     
         69 . The panel of  claim 52  wherein said matting has at least 27% by weight nitrogen in the dry, but uncured state of the melamine resin.  
     
     
         70 . The panel of  claim 68  wherein the glass fibers in the matrix have diameters in the range of 3 to 20 microns.  
     
     
         71 . The panel of  claim 67  wherein said glass fibers are about the same length.  
     
     
         72 . The panel of  claim 70  wherein said glass fibers are about the same length.  
     
     
         73 . The panel of  claim 71  wherein the length of said fibers are approximately 0.75+0.08 inch.  
     
     
         74 . The panel of  claim 72  wherein the length of said fibers are approximately 0.75±0.08 inch.  
     
     
         75 . The panel of  claim 68 , wherein said glass fibers are shorter than 3 inches.  
     
     
         76 . The panel of  claim 70  wherein said glass fibers are shorter than 3 inches.  
     
     
         77 . The panel of  claim 68  wherein said matting has at least 35% by weight nitrogen.  
     
     
         78 . The panel of  claim 68  wherein said melamine resin binder is 5-50% by weight of the finished matting, the glass fibers are 10-95% by weight of the finished matting and further including organic fibers constituting 0-50% by weight of the finished matting.  
     
     
         79 . The panel of  claim 78  wherein said organic fibers come from the group consisting of natural thermoplastic or thermoset polymers.  
     
     
         80 . The panel of  claim 78  wherein said organic fibers come from the group of natural fibers including wood, cotton cellulose derivatives such as rayon or acetate fibers.  
     
     
         81 . The panel of  claim 36  wherein said outer sheet is made of the same fiberglass matting as the dividers.  
     
     
         82 . The panel of  claim 53  wherein said outer sheet is made of the same fiberglass matting as the dividers.  
     
     
         83 . The panel of  claim 54  wherein said outer sheet is made of the same fiberglass matting as the dividers.  
     
     
         84 . The panel of  claim 55  wherein said outer sheet is made of the same fiberglass matting as the dividers.  
     
     
         85 . The panel of  claim 62  wherein said outer sheet is made of the same fiberglass matting as the dividers.  
     
     
         86 . The panel of  claim 63  wherein said outer sheet is made of the same fiberglass matting as the dividers.  
     
     
         87 . The panel of  claim 64  wherein said outer sheet is made of the same fiberglass matting as the dividers.  
     
     
         88 . The panel of  claim 52 ,wherein said connector means is an inner sheet.  
     
     
         89 . The panel of  claim 53  wherein said connector means is an inner sheet.  
     
     
         90 . The panel of  claim 55  wherein said connector means is an inner sheet.  
     
     
         91 . The panel of  claim 62  wherein said connector means is an inner sheet.  
     
     
         92 . The panel of  claim 63  wherein said connector means is an inner sheet.  
     
     
         93 . The panel of  claim 64  wherein said connector means is an inner sheet.  
     
     
         94 . The panel of  claim 88  wherein said inner sheet is made of the same material as said dividers.  
     
     
         95 . The panel of  claim 94  wherein said outer sheet is also made of the same material as said dividers.  
     
     
         96 . The panel of  claim 2  wherein said dividers are individually compressible to permit the outer sheet to be depressed at a single location without deforming the connector means.  
     
     
         97 . The panel of  claim 2  wherein said dividers are individually compressible to permit compression of some dividers without compressing all dividers in the panel.  
     
     
         98 . The panel of  claim 1  or  2  wherein said panel is curvable without effecting its structural integrity.  
     
     
         99 . The panel of  claim 1  or  2  wherein some of said dividers are parallel and other dividers are perpendicular thereto.  
     
     
         100 . The panel of  claim 99  wherein said dividers are elongated and said perpendicular dividers are positioned at opposite longitudinal ends of said parallel dividers.  
     
     
         101 . The panel of  claim 100  wherein said dividers are cellular.  
     
     
         102 . The panel of  claim 101  wherein said dividers in transverse cross-section define a pair of stacked, inverted, truncated triangles.  
     
     
         103 . The panel of  claim 5  wherein said dividers are positioned in closely adjacent relationship except at locations where it is desired to fold the panel along a fold line parallel to said dividers and at said locations, the two dividers closest to said fold line being spaced apart a sufficient distance to permit a folding of the panel along the fold line.  
     
     
         104 . The panel of  claim 103  wherein said dividers have a predetermined width and said two dividers are spaced apart a distance substantially the same as the width of a divider.  
     
     
         105 . The panel of  claim 1  or  2  wherein said panel has a thickness in the range of 12 mm to 26 mm when the dividers are expanded.  
     
     
         106 . The panel of  claim 1  or  2  wherein said panel has a thickness in the range of 3 mm to 4 mm when said at least one divider or dividers are compressed.  
     
     
         107 . The panel of  claim 105  wherein said panel has a thickness in the range of about 3 mm to 4 mm when the panel is compressed.  
     
     
         108 . A structural panel having an outer layer and a cellular structure wherein the cellular structure is made of a fiber glass material.  
     
     
         109 . The panel of  claim 108  wherein said fiberglass material is a fiberglass matting.  
     
     
         110 . The panel of  claim 109  wherein said matting is composed of a glass fiber matrix bonded with a fire retardant melamine resin composition.  
     
     
         111 . The panel of  claim 110  wherein said matting has at least 27% by weight nitrogen in the dry, but uncured state of the melamine resin.  
     
     
         112 . The panel of  claim 110  wherein the glass fibers in the matrix have diameters in the range of 3 to 20 microns.  
     
     
         113 . The panel of  claim 110  or  112  wherein said glass fibers are about the same length.  
     
     
         114 . The panel of  claim 113  wherein the length of the glass fibers is approximately 0.75±0.08 inch.  
     
     
         115 . The panel of  claim 110  or  112  wherein said glass fibers are shorter than 3 inches.  
     
     
         116 . The panel of  claim 108 ,  109 ,  110 ,  111 , or  112  wherein said cellular structure is compressible.  
     
     
         117 . A structural panel having an outer sheet comprised of a plurality of interconnected strips and a cellular structure connected to said outer sheet.  
     
     
         118 . The structural panel of  claim 117  wherein said strips form a part of said cellular structure.  
     
     
         119 . The structural panel of  claim 118  wherein said outer sheet is non-homogenous.  
     
     
         120 . The structural panel of  claim 117  further including an inner sheet on an opposite side of said cellular structure form said outer sheet.  
     
     
         121 . The structural panel of  claim 120  wherein said inner sheet is composed of interconnected strips.  
     
     
         122 . The structural panel of  claim 121  wherein said strips form a part of said cellular structure.  
     
     
         123 . The structural panel of  claim 122  wherein said inner sheet in non-homogenous.  
     
     
         124 . The structural panel of  claim 117  wherein said cellular structure is made from creased strips of material creased along an intermediate portion and along at least one edge to define marginal flaps which are interconnected to form said outer sheet, said flaps defining said strips of the outer sheet.  
     
     
         125 . The structural panel of  claim 124  wherein said creased strips are parallel.  
     
     
         126 . The structural panel of  claim 124  wherein there are two marginal flaps on each creased strip with the marginal flaps defining interconnected strips forming the outer sheet and an inner sheet.  
     
     
         127 . The structural panel of  claim 117  wherein said cellular structure is made from a plurality of creased strips of material creased along an intermediate portion and along at least one edge to define at least one marginal flap and wherein said marginal flaps are secured together by an outer sheet.  
     
     
         128 . The structural panel of  claim 127  wherein there are marginal flaps along each edge of the creased strips with the marginal flaps along one edge being secured together by the outer sheet and along the opposite edge by an inner sheet.  
     
     
         129 . The structural panel of claims  127  and  128  wherein said creased strips are parallel.  
     
     
         130 . The structural panel of  claim 1  or  2  wherein said dividers are of elongated tubular construction and are formed from elongated strips of material.  
     
     
         131 . The panel of  claim 130  wherein said strip include a plurality of longitudinally extending fold lines.  
     
     
         132 . The panel of  claim 131  wherein at least some of said fold lines are folded in an opposite direction from others of said fold lines.  
     
     
         133 . The panel of  claim 132  wherein said elongated tubes in cross section define a pair of stacked, inverted truncated triangles.  
     
     
         134 . The panel of  claim 130  wherein said strips include opposite longitudinal edges which are positioned adjacent to each other.  
     
     
         135 . The panel of  claim 134  wherein said strips, further include elongated fold lines.  
     
     
         136 . The panel of  claim 135  wherein said at least some of said fold lines are folded in an opposite direction from other fold lines.  
     
     
         137 . The panel of  claim 136  wherein said elongated tubes in cross section define a pair of stacked, inverted truncated triangles.  
     
     
         138 . The panel of  claim 137  wherein each truncated triangle defines a base, with one base defining upper surface of the divider and the other base a lower surface of the divider.  
     
     
         139 . The panel of  claim 138  wherein said bases are parallel.  
     
     
         140 . The panel of  claim 138  wherein said lower surface is secured to said outer sheet.  
     
     
         141 . The panel of  claim 140  wherein said longitudinal edges are in said upper surface.  
     
     
         142 . The structural panel of  claim 2  wherein said dividers are of elongated tubular construction having substantially flat upper and lower surfaces, said lower surface being secured to said outer sheet and said upper surface to said connector means.  
     
     
         143 . The structural panel of  claim 142  wherein said dividers have a pair of side partitions with each side partition having an inwardly folded fold line.  
     
     
         144 . The structural panel of  claim 142  wherein said upper surface is smaller than said lower surface.  
     
     
         145 . The structural panel of  claim 143  wherein said upper surface is smaller than said lower surface.  
     
     
         146 . The structural panel of  claim 145  wherein each side partition has an upper portion above the fold line and a lower portion beneath the fold line and wherein said upper portion of each side wall is shorter than said lower portion.  
     
     
         147 . The structural panel of  claim 145  wherein each side partition has an upper portion above the fold line and a lower portion beneath the fold line and wherein said upper and lower portions are substantially the same length.  
     
     
         148 . The panel of  claim 140  wherein the lower surfaces of adjacent dividers are secured to said outer sheet in immediately adjacent relationship with each other.  
     
     
         149 . The panel of  claim 142  wherein the lower surfaces of adjacent dividers are secured to said outer sheet in immediately adjacent relationship with each other and said upper surfaces are connected to said connector means in spaced relationship from each other.  
     
     
         150 . The panel of  claim 143  wherein said upper surface and said lower surface are of the same size.  
     
     
         151 . The panel of  claim 150  wherein said upper surfaces are connected to said connector means in immediate adjacent relationship and said lower surfaces are connected to said outer sheet in immediately adjacent relationship.  
     
     
         152 . A compressible structural panel comprising in combination: 
 at least one outer sheet of material having an inner and outer face,    a plurality of compressible dividers that in a resting condition are expanded and secured to and protrude from said inner face; and    connector means for securing said dividers together at locations distal from said outer sheet;    said dividers comprising elongates strips of material having opposite longitudinal edges and a first set of outer fold lines defining flaps along said edges for attachment to said outer sheet and connector means.    
     
     
         153 . The panel of  claim 152  wherein said dividers further include at least one inner fold line between said outer fold lines.  
     
     
         154 . The panel of  claim 153  wherein there are a pair of inner fold lines.  
     
     
         155 . The panel of  claim 154  wherein said inner fold lines are folded in opposite directions.  
     
     
         156 . The panel of  claim 152  wherein said dividers extend parallel to each other defining cells therebetween.  
     
     
         157 . A compressible panel comprising in combination: 
 at least one outer sheet of material having an inner and outer face, and    a plurality of compressible dividers that in a resting condition are expanded and secured to and protrude from said inner face, said dividers having at least one fold line such that a divider can be folded upon itself along said fold line into a double ply position, and wherein said dividers are made from a glass fiber material wherein the breaking radius of the glass fibers is less than double the thickness of the material.    
     
     
         158 . The panel of  claim 102  wherein said dividers have flat top and bottom surfaces.  
     
     
         159 . A clip for closing one edge of a cellular structural panel wherein said panel has at least one outer sheet of material secured to a plurality of compressible dividers which form cells in the panel when the dividers are expanded, and wherein a portion of the outer sheet and a portion of the dividers have been compressed and are confinable in said clip to close open ends of the remainder of the dividers which are expanded in a cellular condition, said clip comprising: 
 an elongated body of generally J-shaped transverse cross-sectional configuration having a long side, a short side separated from said long side by a connecting wall along one edge of the clip, and a lip projecting from the long side along an opposite edge of the clip from said connecting wall to define an open channel in said clip.    
     
     
         160 . The clip of  claim 159  wherein said connecting wall is substantially perpendicular to said long and short sides.  
     
     
         161 . The clip of  claim 160  wherein said lip is substantially parallel to said connecting wall.  
     
     
         162 . The clip of  claim 161  wherein said lip extends in the same direction from said long side as said connecting wall.  
     
     
         163 . The clip of  claim 162  further including a rib projecting from said long side at said one edge of the clip, said rib projecting in an opposite direction from said long side than said connecting wall.  
     
     
         164 . The clip of  claim 163  wherein said rib extends the full length of said clip.  
     
     
         165 . The clip of  claim 163  or  164  wherein said rib forms an oblique angle with said long side.  
     
     
         166 . The clip of  claim 159 ,  162 , or  163  further including a second elongated body of substantially J-shaped transverse cross-section secured to said first mentioned J-shaped body along said one edge, said second body defining a channel extending perpendicularly to said first mentioned channel.  
     
     
         167 . The clip of  claim 166  wherein said channel in said second body is open along one edge thereof and opens in a direction transverse to said first mentioned channel.  
     
     
         168 . A structural panel and closure clip comprising in combination: 
 a structural panel comprised of at least one outer sheet of material and a plurality of dividers secured to and protruding from one face of said outer sheet, said dividers being parallel with each other and movable from an expanded condition where they protrude from said outer sheet to a compressed condition where they are flattened in closely adjacent relationship with said outer sheet, said dividers in said expanded condition forming a plurality of parallel cells opening at opposite ends of the panel, and    a closure clip having an elongated body of substantially J-shaped transverse cross-section so as to define a channel that is open along one side,    wherein said dividers in said panel have been severed transversely along a line of severance adjacent to one of said ends of said panel and compressed between said line of severance and said one end, said compressed dividers and the outer sheet of material secured thereto being received in said open channel of said closure clip with the closure clip positioned so as to close the open ends of said cells at said one end of the panel.    
     
     
         169 . The combination of  claim 168  wherein said closure clip has a long side, a short side separated from said long side by a connecting wall along one edge of the clip, and a lip projected from the long side along an opposite edge of the clip from said connecting wall.  
     
     
         170 . The combination of  claim 168  wherein said connecting wall is substantially perpendicular to said long and short sides.  
     
     
         171 . The combination of  claim 170  wherein said lip is substantially parallel to said connecting wall.  
     
     
         172 . The combination of  claim 171  wherein said lip extends in the same direction from said long side as said connecting wall.  
     
     
         173 . The combination of  claim 172  wherein said closure clip further includes a rib projecting from said long side at said one edge of the clip, said rib projecting in an opposite direction from said long side than said connecting wall, said rib being adapted to operatively interact with the adjacent open ends of said cells to retain the closure clip in a position closing the open ends of said cells.  
     
     
         174 . The combination of  claim 173  wherein said rib extends the full length of said clip.  
     
     
         175 . The combination of  claim 173  or  174  wherein said rib forms an oblique angle with said long side.  
     
     
         176 . The combination of claims  169 ,  172 ,  173  wherein said clip further includes a second elongated body of substantially J-shaped transverse cross-section secured to said first mentioned J-shaped body along said one edge, said second body defining a channel extending perpendicularly to said first mentioned channel.  
     
     
         177 . The combination of  claim 176 , wherein said channel in said second body is open along one edge thereof and opens in a direction transverse to said first mentioned channel.  
     
     
         178 . The combination of  claim 176  further including a matrix of elongated support members having support ledges thereon, said support ledges being received in said channels of said second bodies to support a set of said structural panels on said support members.  
     
     
         179 . The combination of  claim 178  wherein said support members are of inverted T-shaped transverse cross-section having a vertical main body and a cross member across lower edge of said main body, said cross member defining said support ledges on opposite sides of said main body.  
     
     
         180 . The combination of  claim 179  further including a second set of panels supported on top surfaces of said support ledges such that said second set of panels are superimposed over said first set of panels.  
     
     
         181 . The combination of  claim 180  wherein said panels of the second set are structurally different from said panels of the first set.  
     
     
         182 . The combination of  claim 180  wherein said panels of the second set are structurally the same as the panels of the first set.  
     
     
         183 . A method of folding a panel along a fold line, said panel having an outer sheet and a plurality of individual elongated cells extending parallel to said fold line secured to said outer sheet and protruding from one face of said outer sheet, said cells being positioned closely adjacent to each other comprising the steps of: 
 removing a cell from said outer sheet adjacent to said fold line, and    folding the panel along said fold line.    
     
     
         184 . A structural panel comprising in combination an outer sheet of material and a plurality of adjacent dividers secured to and protruding from the outer sheet, said dividers having fold lines therein allowing the dividers to be folded in either direction along said fold lines and when folded in one direction the dividers are compressible into closely adjacent relationship with said outer sheet but when folded in the opposite direction abut an adjacent divider to reinforce the adjacent divider and render the panel substantially incompressible, said dividers being made of a material that biases the material toward a flat orientation even after having been folded and the bias urging the dividers to fold in said opposite direction whereby the panel can be compressed by folding the dividers in said one direction but when allowed to decompress will effect folding of the dividers in the opposite direction to render the panel substantially incompressible.  
     
     
         185 . The panel of  claim 184  wherein said dividers are made of a glass fiber bonded together with a mixture of a thermoset resin and a thermoplastic resin.  
     
     
         186 . A method of manufacturing a structural panel such that it is self expanding from a compressed condition to an expanded substantially incompressible condition, comprising the steps of: 
 providing an outer sheet of material,    providing a plurality of elongated dividers having fold lines therealong such that the dividers can be folded in either direction along said fold lines, said dividers being made of glass fibers that are bonded together with a mixture of thermoset and thermoplastic resin such that the dividers are biased toward a flat condition even after having been folded, and    securing the dividers to the outer sheet along one side thereof in closely adjacent relationship such that when the dividers are folded in a first direction along said fold lines the panel can be compressed with the dividers in closely adjacent relationship to said outer sheet and when folded in an opposite direction the dividers abut adjacent dividers to reinforce the dividers rendering the panel substantially incompressible.    
     
     
         187 . The method of  claim 186  further including the step of increasing the amount of thermoplastic in the mixture to extend the time period in which the dividers move from the compressed condition to the expanded condition.  
     
     
         188 . The method of  claim 186  or  187  further including the step of securing a connector means to an opposite side of said dividers from said one side where the dividers are connected to the outer sheet to prevent the dividers from expanding to a flat condition.  
     
     
         189 . A compressible structural panel having a noise reduction coefficient in excess of 0.8 at 125 Hz.  
     
     
         190 . A compressible structural panel having a noise reduction coefficient in excess of 0.9 at 250 Hz.  
     
     
         191 . A compressible structural panel having a noise reduction coefficient in excess of 0.9 at 4000 Hz.  
     
     
         192 . A compressible structural panel of  claim 189  or  190  further having a noise reduction coefficient in excess of 0.9 at 4000 Hz.  
     
     
         193 . The compressible structural panel of  claim 190  further having a noise reduction coefficient in excess of 0.8 at 125 Hz.  
     
     
         194 . The compressible structural panel according to  claim 189 ,  191 , or  193  wherein said panel has a thickness in the range of 12 mm to 26 mm.  
     
     
         195 . The compressible structural panel according to  claim 192  wherein said panel has a thickness in the range of 12 mm to 26 mm.  
     
     
         196 . The compressible structural panel of  claim 194  wherein said panel is compressible to a thickness in the range of 32 mm to 4 mm.  
     
     
         197 . The compressible structural panel of  claim 195  wherein said panel is compressible to a thickness in the range of 32 mm to 4 mm.  
     
     
         198 . A compressible divider for use in a structural panel comprising: 
 an elongated strip of material having fold lines therein such that said strip of material can be folded upon itself when compressed.    
     
     
         199 . The divider of  claim 198  wherein said strip of material is semi-rigid.  
     
     
         200 . The divider of  claim 198  wherein said divider has an expanded rest condition from which it can be compressed into a compressed condition.  
     
     
         201 . The divider of  claim 200  wherein said divider is biased toward its expanded condition.  
     
     
         202 . The divider of  claim 201  wherein said fold lines define flaps along edges of the strip of material and partitions between said flaps.  
     
     
         203 . The divider of  claim 202  wherein there are fold lines in said portions such that the partitions can fold upon themselves.  
     
     
         204 . The divider of  claim 203  wherein said flaps and partitions are positioned in face-to-face relationship when the divider is in the compressed condition.  
     
     
         205 . The divider of  claim 198 ,  200  or  202  wherein said strip of material is fiberglass including a plurality of glass fibers bonded together with a resin.  
     
     
         206 . The divider of  claim 205  wherein said resin is a thermoset resin.  
     
     
         207 . The divider of  claim 205  wherein said resin is a thermoplastic resin.  
     
     
         208 . The divider of  claim 205  wherein said resin is a combination of thermoset and thermoplastic resins.  
     
     
         209 . The divider of  claim 202  wherein said partitions each include a longitudinal fold line so as to define a pair of partition portions on each partition.  
     
     
         210 . The divider of  claim 209  wherein said divider portions are of the same size.  
     
     
         211 . The divider of  claim 209  wherein said divider portions are of different sizes.  
     
     
         212 . The divider of  claim 198 ,  200  or  202  wherein said strip of material is made of fiberglass matting.  
     
     
         213 . The divider of  claim 212  wherein said matting is composed of a glass fiber matrix bonded with a fire retardant melamine resin composition.  
     
     
         214 . The divider of  claim 213  wherein said matting has at least 27% by weight nitrogen in the dry, but uncured state of the melamine resin.  
     
     
         215 . The divider of  claim 213  wherein the glass fibers in the matrix have diameter sin the range of 3 to 20 microns.  
     
     
         216 . The divider of  claim 213  wherein said glass fibers are about the same length.  
     
     
         217 . The divider of  claim 216  wherein the length of said fibers is approximately 0.75±0.08 inch.  
     
     
         218 . The divider of  claim 213  wherein the length of said fibers is less than 3 inches.  
     
     
         219 . The divider of  claim 213  wherein said melamine resin has at least 35% by weight nitrogen.  
     
     
         220 . The divider of  claim 213  wherein said melamine resin is 5-50% by weight of the finished matting the glass fibers are 10-95% by weight of the finished matting and further including organic fibers constituting 0-50% by weight of the finished matting.  
     
     
         221 . The divider of  claim 220  wherein said organic fibers come from the group consisting of thermoplastic or thermoset polymers.  
     
     
         222 . The divider of  claim 220  wherein said organic fibers come from the group of natural fibers including wood, cotton and cellulose derivatives such as rayon or acetate fibers.