1 00:00:00,000 --> 00:00:10,808 *36C3 preroll music* 2 00:00:13,623 --> 00:00:21,449 Herald Angel Noujoum: Hello and welcome to our next talk, 3 00:00:21,449 --> 00:00:26,630 Why 3D printing clothes is NOT the future. Short question to the audience: 4 00:00:26,630 --> 00:00:32,103 Who of you has already 3D printed anything? Please raise your hand. 5 00:00:32,103 --> 00:00:35,640 That's what I thought, I estimate that's about 80 % of the audience in this hall. 6 00:00:35,640 --> 00:00:38,860 I am not surprised, it is the topic of this talk, that's why you are here. 7 00:00:38,860 --> 00:00:41,606 Second question: Who of you 8 00:00:41,606 --> 00:00:47,059 has already tried 3D printing clothes? Please raise your hand again. 9 00:00:47,059 --> 00:00:54,539 I see four people. So, how did it go? 10 00:00:54,539 --> 00:00:58,082 One person indicates that it worked out well, 11 00:00:58,082 --> 00:01:02,399 the others are showing hand gestures of "not that well". 12 00:01:02,399 --> 00:01:05,513 Who of all the people that have already 3D printed 13 00:01:05,513 --> 00:01:09,930 has thought about printing clothes? 14 00:01:09,930 --> 00:01:12,869 Ok, about 10 people have thought about that. 15 00:01:12,869 --> 00:01:17,540 Our next speaker, Rebekka, will tell you why it might not be the best idea 16 00:01:17,540 --> 00:01:22,320 to 3D print clothes. On the internet 17 00:01:22,320 --> 00:01:27,270 and especially Twitter, Rebekka is known by her nickname Kurfuerstin 18 00:01:27,270 --> 00:01:31,619 and she is a clothing technician. Her research includes 19 00:01:31,619 --> 00:01:35,120 traditional apparel production, she has worked in a fashion company, 20 00:01:35,120 --> 00:01:38,737 at the theater and at a tv show. 21 00:01:38,737 --> 00:01:42,459 Also, she is researching innovative techniques such as 3D printing 22 00:01:42,459 --> 00:01:46,963 and virtual clothing simulation, 23 00:01:46,963 --> 00:01:50,709 meaning software that realistically simulates clothes 24 00:01:50,709 --> 00:01:55,770 on a virtual avatar. 25 00:01:55,770 --> 00:01:58,940 Have fun with the talk , I hope you will learn a lot 26 00:01:58,940 --> 00:02:01,953 and please welcome Rebekka 27 00:02:01,953 --> 00:02:03,663 with a round of applause. Thank you. 28 00:02:03,663 --> 00:02:08,490 *applause* 29 00:02:08,490 --> 00:02:12,280 Speaker Rebekka/Kurfuerstin: I just received some mail really quick, 30 00:02:12,280 --> 00:02:17,312 but that won't stop me from giving my talk. Welcome, 31 00:02:17,312 --> 00:02:22,140 nice to see you all here, in this hall and on the live stream and... 32 00:02:22,140 --> 00:02:26,480 additional mail, okay, a lot happening on this stage. I will maybe read that later, 33 00:02:26,480 --> 00:02:33,079 but it is great to know that the post office system works! 34 00:02:33,079 --> 00:02:38,129 The title of my talk is "Why 3D printing clothes is NOT the future". 35 00:02:38,129 --> 00:02:44,087 It will be about the properties of 3D printed clothes and 36 00:02:44,087 --> 00:02:50,599 what would need to happen in order for it to be a serious alternative 37 00:02:50,599 --> 00:02:54,402 for everyday wear. I was just introduced as a clothing technician. 38 00:02:54,402 --> 00:02:57,749 In case you don't know what this strange combination of words means, 39 00:02:57,749 --> 00:03:03,689 clothes and technology, a short explanation. 40 00:03:03,689 --> 00:03:07,319 When clothes are made, at one side, 41 00:03:07,319 --> 00:03:12,511 you have the design, the idea. But the realization, the production, 42 00:03:12,511 --> 00:03:16,989 happens somewhere else entirely and by some other person. 43 00:03:16,989 --> 00:03:20,920 In a simplified way, a person creates the design for a dress 44 00:03:20,920 --> 00:03:24,069 and says: I designed this dress. 45 00:03:24,069 --> 00:03:29,520 So they have a nice picture from which you can learn some information, but not much. 46 00:03:29,520 --> 00:03:33,560 And they go to a factory and say: please make this dress. 47 00:03:33,560 --> 00:03:37,720 The production will kindly ask: where is the table of information? 48 00:03:37,720 --> 00:03:41,650 Because the production site wants to have all the information about the dress. 49 00:03:41,650 --> 00:03:47,099 And the designer then asks: what? And the production then asks: what? 50 00:03:47,099 --> 00:03:49,920 And that would be the end of it. 51 00:03:49,920 --> 00:03:53,529 Because the factory wants to know, which fabric do we need for the dress, 52 00:03:53,529 --> 00:03:58,730 and how much? Which sizes will be made, and how many dresses in which sizes? 53 00:03:58,730 --> 00:04:02,360 Which machines do we need for that, what text will be on the care instruction labels 54 00:04:02,360 --> 00:04:05,760 and what will be the exact position of the labels on the side seam in cm? 55 00:04:05,760 --> 00:04:11,360 All those questions cannot be answered by the illustration of the dress. 56 00:04:11,360 --> 00:04:14,959 And that is where clothing technology comes in, as the intersection between design and production. 57 00:04:14,959 --> 00:04:20,570 It's about the technical feasibility and 58 00:04:20,570 --> 00:04:25,110 what needs to be done to manufacture clothes. 59 00:04:25,110 --> 00:04:29,590 It's about materials, quality, prices and locations. 60 00:04:29,590 --> 00:04:34,710 Where should the production take place, and when? 61 00:04:34,710 --> 00:04:37,610 All these questions need answers and that is the responsibility 62 00:04:37,610 --> 00:04:43,169 of clothing technicians. And this kind of reality check, 63 00:04:43,169 --> 00:04:48,379 the perspective of feasibility, is the perspective I also chose to examine 3D printing. 64 00:04:48,379 --> 00:04:52,090 If you search for the words "3D print" and "clothes", you will get headlines like these. 65 00:04:52,090 --> 00:04:58,930 For example: 3D printing will bring flexibility into the fashion industry. 66 00:04:58,930 --> 00:05:03,110 Or: The fashion of the future. Or: Will the street wear of the future be 3D printed? 67 00:05:03,110 --> 00:05:08,020 Or: Can 3D printing fundamentally change the fashion industry? 68 00:05:08,020 --> 00:05:12,070 A few years ago, the headlines were even more sensational. 69 00:05:12,070 --> 00:05:15,759 They were predicting that by 2020, we would print a sweater in the morning, 70 00:05:15,759 --> 00:05:19,270 melt it down in the evening and then print a new one the next day. 71 00:05:19,270 --> 00:05:21,700 Nowadays, the predictions have become a bit more careful, 72 00:05:21,700 --> 00:05:24,400 at least with a question mark at the end. 73 00:05:24,400 --> 00:05:28,889 But even from these headlines, you get the sense that something 74 00:05:28,889 --> 00:05:33,423 will fundamentally change the fashion industry. 75 00:05:33,423 --> 00:05:37,990 There is also the hope of a sustainable production 76 00:05:37,990 --> 00:05:41,180 with the argument, that the procedure of 3D printing is sustainable. 77 00:05:41,180 --> 00:05:45,287 Sustainability is a major topic in the fashion industry. 78 00:05:45,287 --> 00:05:48,539 The question is if 3D printing might be the solution. 79 00:05:48,539 --> 00:05:54,569 Clothes have already been 3D printed, 80 00:05:54,569 --> 00:05:58,289 it's not even that new or unrealistic. 81 00:05:58,289 --> 00:06:02,300 There are entire 3D printed collections and I will show some examples now. 82 00:06:02,300 --> 00:06:07,990 In Israel, Danit Peleg printed her entire final collection of five outfits. 83 00:06:07,990 --> 00:06:13,169 In Israel, Danit Peleg printed her entire final collection of five outfits. 84 00:06:13,169 --> 00:06:18,449 One example is the two piece outfit on the right, a top and a floor length skirt. 85 00:06:18,449 --> 00:06:25,110 The skirt has been printed using only desktop printers, 86 00:06:25,110 --> 00:06:30,169 meaning that it consists of modules of A4 size 87 00:06:30,169 --> 00:06:34,169 that have been connected afterwards. 88 00:06:34,169 --> 00:06:37,930 It is flexibel, because it was printed with a flexible filament, 89 00:06:37,930 --> 00:06:42,160 but also because it made up of a zigzag structure 90 00:06:42,160 --> 00:06:45,936 that allows for it to pull on it. 91 00:06:45,936 --> 00:06:50,889 If you pull it up, it bounces up and down. 92 00:06:50,889 --> 00:06:55,020 The jacket is the first 3D printed ready-to-wear 93 00:06:55,020 --> 00:07:00,039 article of clothing that you can order online, 94 00:07:00,039 --> 00:07:04,970 in limited edition of 100 pieces. 95 00:07:04,970 --> 00:07:10,400 It costs 1500 $. 96 00:07:10,400 --> 00:07:13,860 You can choose the color and some writing on the back 97 00:07:13,860 --> 00:07:17,991 and then the jacket will be printed in 100 hours. 98 00:07:17,991 --> 00:07:24,110 Another example is from the design collective Nervous System, 99 00:07:24,110 --> 00:07:28,969 who have developed the Kinematics System. 100 00:07:28,969 --> 00:07:32,910 It consists of triangles that are connected by hinges, 101 00:07:32,910 --> 00:07:38,397 making the whole structure flexible. 102 00:07:38,397 --> 00:07:43,830 But it is made of a hard material. It can move, but it is not elastic 103 00:07:43,830 --> 00:07:48,530 and it rattles a bit when you move. They also developed an opaque version. 104 00:07:48,530 --> 00:07:53,199 The dress on the right is based on the same triangle structure, 105 00:07:53,199 --> 00:07:58,291 but there are some kind of petals on top of it. 106 00:07:58,291 --> 00:08:03,650 So the dress is opaque. 107 00:08:03,650 --> 00:08:09,530 A third example is the Pangolin Dress 108 00:08:09,530 --> 00:08:13,159 which is also made of a structure of interlocked modules 109 00:08:13,159 --> 00:08:16,360 that can move on top of and into each other, 110 00:08:16,360 --> 00:08:21,789 thus making the structure flexible. 111 00:08:21,789 --> 00:08:27,449 You can move in the dress and the dress adjusts to your movements. 112 00:08:27,449 --> 00:08:31,148 One of the people working on it is Travis Fitch, a designer working in New York. 113 00:08:31,148 --> 00:08:35,229 I contacted Travis and said: I am a clothing technician, I love numbers. 114 00:08:35,229 --> 00:08:39,473 How do you know if a newly developed structure is suitable for a dress? 115 00:08:39,473 --> 00:08:43,959 How do you know if the elasticity is high enough 116 00:08:43,959 --> 00:08:49,500 to use it in a piece of clothing? 117 00:08:49,500 --> 00:08:53,890 Do you do laboratory tests? 118 00:08:53,890 --> 00:08:59,630 And he answered, well, I pull at it and then I either say it is okay or not. 119 00:08:59,630 --> 00:09:03,040 So the clothing technician in me came through and said, 120 00:09:03,040 --> 00:09:08,490 well how about numbers? So I offered to test some of his structures, 121 00:09:08,490 --> 00:09:15,010 to conduct some laboratory experiments 122 00:09:15,010 --> 00:09:18,930 in order to examine how the properties can be expressed in numbers and units. 123 00:09:18,930 --> 00:09:23,324 Those were only three examples. There are many more 124 00:09:23,324 --> 00:09:29,070 on catwalks and in fashion shows. It is clear that those examples are not everyday wear. 125 00:09:29,070 --> 00:09:34,410 They are special made-to-order products, 126 00:09:34,410 --> 00:09:38,200 it takes months to create them, 127 00:09:38,200 --> 00:09:42,529 they consist of 300 different pieces that need to be assembled. 128 00:09:42,529 --> 00:09:47,190 But the headlines about fundamentally changing the fashion industry 129 00:09:47,190 --> 00:09:50,660 are about everyday wear. 130 00:09:50,660 --> 00:09:55,043 Custom-made items on a catwalk do not change the whole industry. 131 00:09:55,043 --> 00:09:58,720 Something needs to happen before that applies to everyday wear. 132 00:09:58,720 --> 00:10:03,779 That is why I ask, what kind of properties do clothes need to have 133 00:10:03,779 --> 00:10:07,870 in order to be everyday wear, meaning clothes 134 00:10:07,870 --> 00:10:13,846 that we can wear every day and for every occasion? 135 00:10:13,846 --> 00:10:19,310 First of all, clothes need to be comfortable. 136 00:10:19,310 --> 00:10:24,300 There are four aspects of wearing comfort. 137 00:10:24,300 --> 00:10:29,540 First, the psychological wearing comfort which is about fashion trends, 138 00:10:29,540 --> 00:10:36,379 societal norms and individuality. 139 00:10:36,379 --> 00:10:40,240 The fact that I am standing here in a t-shirt and a hoodie 140 00:10:40,240 --> 00:10:44,339 is particularly apt for this congress. 141 00:10:44,339 --> 00:10:47,610 On another business conference I might have worn something different. 142 00:10:47,610 --> 00:10:52,360 And that people are driving around in onesies and goose costumes 143 00:10:52,360 --> 00:10:57,856 is also very specific for this group right here. *laughter* 144 00:10:57,856 --> 00:11:01,661 What I mean by this is that people feel comfortable wearing this in this specific context 145 00:11:01,661 --> 00:11:04,120 and might not feel at ease in another context, 146 00:11:04,120 --> 00:11:06,510 although the clothes themselves have not changed. 147 00:11:06,510 --> 00:11:11,220 That is the psychological wearing comfort. 148 00:11:11,220 --> 00:11:16,310 The next-to-skin-comfort is about the feeling of something on the skin. 149 00:11:16,310 --> 00:11:21,420 Surfaces can be soft or scratchy, they can also cause allergies. 150 00:11:21,420 --> 00:11:26,190 So it is about the direct contact on the skin. 151 00:11:26,190 --> 00:11:30,930 The physiological wearing comfort is very important as well. It's about the climate control 152 00:11:30,930 --> 00:11:35,055 of the body and about how clothes can keep us warm but also allow for moisture to evaporate. 153 00:11:35,055 --> 00:11:38,890 The human body has this amazing system of protecting us from overheating. 154 00:11:38,890 --> 00:11:44,490 We start to sweat and the moisture evaporates. 155 00:11:44,490 --> 00:11:49,540 But the evaporation has to happen through the fabric of our clothes. 156 00:11:49,540 --> 00:11:54,100 Some clothes allow for better evaporation than others. 157 00:11:54,100 --> 00:11:58,870 This aspect is incredibly important for our comfort when wearing clothes. 158 00:11:58,870 --> 00:12:05,209 The fourth aspect is the ergonomical wearing comfort 159 00:12:05,209 --> 00:12:10,811 which is about freedom of movement and that is what I examined in detail. 160 00:12:10,811 --> 00:12:14,639 Freedom of movement in clothes is achieved by the fit of a piece of clothing, 161 00:12:14,639 --> 00:12:20,350 mainly meaning how tight it is on the body. 162 00:12:20,350 --> 00:12:25,860 Secondly, it is achieved by the elasticity of the materials used. 163 00:12:25,860 --> 00:12:29,380 This is very important because there are parts of our body where we need 50% stretching, 164 00:12:29,380 --> 00:12:35,070 for example at our knees and elbows. 165 00:12:35,070 --> 00:12:38,790 If you move your arm like this, then the clothes need to allow this movement 166 00:12:38,790 --> 00:12:42,019 without tearing apart. 167 00:12:42,019 --> 00:12:47,670 Without elasticity, the sleeve would be destroyed 168 00:12:47,670 --> 00:12:51,940 or would change its form and create buckles. 169 00:12:51,940 --> 00:12:56,570 If we have a very tight sleeve 170 00:12:56,570 --> 00:13:00,300 made from a material that is not elastic 171 00:13:00,300 --> 00:13:03,486 the sleeve at the elbow would take the shape of our elbow. 172 00:13:03,486 --> 00:13:07,796 So we need a material with the capability to rebound. 173 00:13:07,796 --> 00:13:10,579 After we have moved the arm like this, the sleeve at the elbow 174 00:13:10,579 --> 00:13:15,230 will go back to its original shape. 175 00:13:15,230 --> 00:13:18,730 So if a material is not elastic, it is not that suitable for clothes. 176 00:13:18,730 --> 00:13:22,000 It is possible, but then it needs to be compensated by the cut of the clothes, 177 00:13:22,000 --> 00:13:25,199 in that case, it cannot be too tight. If a piece of clothing is loose fit, 178 00:13:25,199 --> 00:13:29,160 the elasticity of the fabric is not that important. 179 00:13:29,160 --> 00:13:35,339 I wanted to examine the influencing factors on the elastic properties 180 00:13:35,339 --> 00:13:39,389 of 3D printed structures in order to actively influence the elasticity. 181 00:13:39,389 --> 00:13:43,315 This could be used 182 00:13:43,315 --> 00:13:47,226 to enhance the wearing comfort of 3D printed clothes 183 00:13:47,226 --> 00:13:54,320 and thereby get us a bit closer to 3D printed everyday wear. 184 00:13:54,320 --> 00:13:59,805 Elasticity in textile structures, fabrics, is achieved by two aspects. 185 00:13:59,805 --> 00:14:04,050 First, a material itself can be elastic. 186 00:14:04,050 --> 00:14:08,260 In fabrics, this is mostly elastane. 187 00:14:08,260 --> 00:14:11,720 Elastane can be stretched 300% and will return to its original length. 188 00:14:11,720 --> 00:14:15,758 It is used in a majority of clothes, 189 00:14:15,758 --> 00:14:22,860 mostly in the ratio 98% cotton and 2% elastane. 190 00:14:22,860 --> 00:14:26,903 2% are enough to make a shirt elastic enough to easily put it on 191 00:14:26,903 --> 00:14:31,967 while at the same time being tight and not starting to buckle after wearing. 192 00:14:31,967 --> 00:14:36,170 The second possibility is structural elasticity. 193 00:14:36,170 --> 00:14:41,370 In clothing, this is mainly achieved by creating knitwear. 194 00:14:41,370 --> 00:14:47,320 If you pull at knitwear, 195 00:14:47,320 --> 00:14:50,579 the loops will change their shape. 196 00:14:50,579 --> 00:14:54,870 In this manner, you can create an elastic structure, 197 00:14:54,870 --> 00:14:59,903 even with materials with low elasticity. 198 00:14:59,903 --> 00:15:04,994 For example, cotton fibers are not very elastic. But if you create a knitwear 199 00:15:04,994 --> 00:15:07,949 made of cotton threads, the fabric can be very flexible and elastic. 200 00:15:07,949 --> 00:15:13,899 In 3D printed structures, 201 00:15:13,899 --> 00:15:18,660 an elastic material can be used as well, for example TPU. 202 00:15:18,660 --> 00:15:23,449 TPU is short for thermoplastic polyurethane. Polyurethane is a primary part of elastane, too. 203 00:15:23,449 --> 00:15:28,360 So TPU and elastane have very similar properties based on their chemical composition. 204 00:15:28,360 --> 00:15:38,259 Structural elasticity is also possible. 205 00:15:38,259 --> 00:15:43,680 It is possible to print meshes, 206 00:15:43,680 --> 00:15:48,459 but you can also create different shapes like curves, arches, helices or springs. 207 00:15:48,459 --> 00:15:53,050 In short, shapes that you can compress or pull at, 208 00:15:53,050 --> 00:15:58,350 so that you will first pull at the structure before pulling at the material itself. 209 00:15:58,350 --> 00:16:02,180 However, the design depends on the printing method. There are several 210 00:16:02,180 --> 00:16:06,380 different methods and not all of them are equally suited to create certain shapes. 211 00:16:06,380 --> 00:16:11,550 For my research, I focused on two of them. 212 00:16:11,550 --> 00:16:16,360 First, the FLM, short for fused layer modeling, 213 00:16:16,360 --> 00:16:20,779 sometimes also called FDM, short for fused deposition modeling. 214 00:16:20,779 --> 00:16:25,197 You heat a thermoplastic filament 215 00:16:25,197 --> 00:16:29,759 and push it through a nozzle 216 00:16:29,759 --> 00:16:33,839 The nozzle then lays the strand of material on the printing bed. 217 00:16:33,839 --> 00:16:39,720 All layers on top of each other make the object. 218 00:16:39,720 --> 00:16:46,230 If an object has an overhang like the shape on the left, 219 00:16:46,230 --> 00:16:50,920 you need support structures. 220 00:16:50,920 --> 00:16:56,029 In every layer, the extruder will also build the supporting columns. 221 00:16:56,029 --> 00:17:00,000 When the object is finished, 222 00:17:00,000 --> 00:17:04,530 the support structures can be removed. 223 00:17:04,530 --> 00:17:09,258 This is not a problem for hard materials, 224 00:17:09,258 --> 00:17:13,770 you can easily break it off and sand the surface. 225 00:17:13,770 --> 00:17:17,890 But for elastic materials, it's a different situation. 226 00:17:17,890 --> 00:17:22,220 If you pull at it, it will not break off, but simply stretch. 227 00:17:22,220 --> 00:17:26,859 So if you want to print elastic shapes with overhangs or interlockings, 228 00:17:26,859 --> 00:17:31,759 this method is not recommended. 229 00:17:31,759 --> 00:17:34,700 The support structures cannot be broken off, 230 00:17:34,700 --> 00:17:38,380 they would have to be cut off with scissors, 231 00:17:38,380 --> 00:17:41,309 so that would take a long time. 232 00:17:41,309 --> 00:17:43,090 Interjection: Water soluble support structures! 233 00:17:43,090 --> 00:17:47,345 Speaker: Yes, good idea, unfortunately that does not work for TPU yet. 234 00:17:47,345 --> 00:17:49,890 Waterbased support structures are usually made of PVA. 235 00:17:49,890 --> 00:17:54,392 you can remove them with water afterwards. 236 00:17:54,392 --> 00:18:01,730 But the melting temperatures of PVA and TPU do not match. 237 00:18:01,730 --> 00:18:06,880 TPU requires a very high temperature, I printed with 215°C. 238 00:18:06,880 --> 00:18:10,564 At this temeprature, PVA is already decomposing, its melting temperature is lower. 239 00:18:10,564 --> 00:18:16,960 So it is a good idea, but at the moment it does not work yet. 240 00:18:16,960 --> 00:18:21,390 I am sure that something will be developed 241 00:18:21,390 --> 00:18:26,720 to solve this problem, though. 242 00:18:26,720 --> 00:18:30,410 The other method is SLS, short for selective laser sintering. 243 00:18:30,410 --> 00:18:34,500 An entire layer of powder is laid on the build plate. 244 00:18:34,500 --> 00:18:40,391 A laser melts the fine grain powder in order 245 00:18:40,391 --> 00:18:44,370 to create the desired shape layer by layer. In this case, 246 00:18:44,370 --> 00:18:50,001 the powder itself is the support structure, so you do not need to print 247 00:18:50,001 --> 00:18:56,480 supporting columns. In the end, the entire printer is filled with a block of powder 248 00:18:56,480 --> 00:19:00,794 and somewhere in there, the object can be found. 249 00:19:00,794 --> 00:19:06,970 The powder is removed and can be reused. 250 00:19:06,970 --> 00:19:13,570 For my research, I examined several structures. 251 00:19:13,570 --> 00:19:17,929 The ones on the left and in the middle are created from powder. 252 00:19:17,929 --> 00:19:25,380 So it was possible to create some height and chain-like shapes. 253 00:19:25,380 --> 00:19:32,400 I had different sizes. 254 00:19:32,400 --> 00:19:36,909 The smaller size is much more flexible, 255 00:19:36,909 --> 00:19:43,070 you can easily move it and fold it. 256 00:19:43,070 --> 00:19:46,470 The modules can be shifted into each other. 257 00:19:46,470 --> 00:19:51,239 You can compress it and pull at it and the structure is very flexible. 258 00:19:51,239 --> 00:19:57,667 As I said, for the other 3D printing method, the possibilities in shape were limited. 259 00:19:57,667 --> 00:20:01,850 This structure is based on a pattern of rhombs that was extruded. 260 00:20:01,850 --> 00:20:08,780 If you pull at it, the shape of the rhomb changes 261 00:20:08,780 --> 00:20:13,264 before the material itself is strained. 262 00:20:13,264 --> 00:20:16,620 Again, I had different variations in size and height 263 00:20:16,620 --> 00:20:21,600 in order to examine the influencing factors on the elastic properties. 264 00:20:21,600 --> 00:20:26,279 in order to examine the influencing factors on the elastic properties. 265 00:20:26,279 --> 00:20:30,489 How can you examine elastic properties at all? 266 00:20:30,489 --> 00:20:36,215 How can you examine elastic properties at all? 267 00:20:36,215 --> 00:20:41,211 With a so-called tensile test. 268 00:20:41,211 --> 00:20:47,370 You don't test a piece of clothing, you only test a fabric swatch. 269 00:20:47,370 --> 00:20:53,060 The swatch is clamped into a tensile test machine which then pulls with constant velocity. 270 00:20:53,060 --> 00:20:57,501 The corresponding software automatically creates a diagram like the one on the right. 271 00:20:57,501 --> 00:21:03,480 It shows the elongation in %, 272 00:21:03,480 --> 00:21:08,250 meaning how long the fabric swatch has been stretched, 273 00:21:08,250 --> 00:21:12,230 and on the other axis the tensile strength in N, 274 00:21:12,230 --> 00:21:18,090 how much strength is needed in order to achieve this elongation of the fabric swatch. 275 00:21:18,090 --> 00:21:23,370 This diagram shows the elongation, the elasticity and the tensile strength. 276 00:21:23,370 --> 00:21:26,820 I need to stress that elongation and elasticity is not the same. 277 00:21:26,820 --> 00:21:33,160 You can stretch something and it might have just gotten longer. 278 00:21:33,160 --> 00:21:37,490 If I stretch something 279 00:21:37,490 --> 00:21:41,179 and it returns to its original length, it is elastic. 280 00:21:41,179 --> 00:21:45,730 So that is a different property, 281 00:21:45,730 --> 00:21:51,190 which you can also gather from the stress-elongation-diagram. 282 00:21:51,190 --> 00:21:57,030 I tested all of my structures this way. 283 00:21:57,030 --> 00:22:01,110 Of course, you need to test several specimen in order to generate average values. 284 00:22:01,110 --> 00:22:05,656 So I had my numbers and units. 285 00:22:05,656 --> 00:22:09,650 But what do I do with that? 286 00:22:09,650 --> 00:22:17,059 I still need to know if these numbers are good or bad. There is a recommendation 287 00:22:17,059 --> 00:22:22,799 by the Dialog Textil Bekleidung in cooperation with the German Fashion Mode Verband, 288 00:22:22,799 --> 00:22:27,860 It is not a standard or a law, clothes do not have to have these properties. 289 00:22:27,860 --> 00:22:32,350 But it is a recommendation, what stretch properties clothing should approximately have 290 00:22:32,350 --> 00:22:37,640 and what kind of forces they should withstand. 291 00:22:37,640 --> 00:22:41,370 This is a small extract. It is divided by products, 292 00:22:41,370 --> 00:22:46,020 so trousers and skirts have different specifications opposed to underwear. 293 00:22:46,020 --> 00:22:50,299 If it is far from the body, meaning loose fit, lower tensile strengths suffice. 294 00:22:50,299 --> 00:22:54,514 If a piece of clothing is loose fit, 295 00:22:54,514 --> 00:23:00,610 the stretching properties are not that important. 296 00:23:00,610 --> 00:23:03,270 So I compared these numbers to mine and I found 297 00:23:03,270 --> 00:23:08,039 that the elongations of my structures were great. 298 00:23:08,039 --> 00:23:13,591 But the maximum force was not reached. 299 00:23:13,591 --> 00:23:18,040 So I can stretch my structures just fine, 300 00:23:18,040 --> 00:23:24,340 but I do not need a lot of force to tear them apart and that is a bad result. 301 00:23:24,340 --> 00:23:28,850 If I bend my elbow and the sleeve is destroyed, 302 00:23:28,850 --> 00:23:32,520 I do not want to use this structure for clothes. 303 00:23:32,520 --> 00:23:35,870 So the tensile strength of the 3D printed structures is lower 304 00:23:35,870 --> 00:23:41,180 than the recommended properties for clothes. 305 00:23:41,180 --> 00:23:45,279 I also wanted to examine the influencing factors on the elastic properties. 306 00:23:45,279 --> 00:23:51,090 From my results, I could see that the size of the modules influences the properties. 307 00:23:51,090 --> 00:23:56,929 The larger sizes show higher values than the smaller variations. 308 00:23:56,929 --> 00:24:01,864 However, the larger variations do not feel and move like fabric. 309 00:24:01,864 --> 00:24:07,018 The smaller variations are more fabric-like, 310 00:24:07,018 --> 00:24:11,115 but they didn't show very good tensile strengths. 311 00:24:11,115 --> 00:24:15,240 Aside from that, there was another influencing factor: the slicing software. 312 00:24:15,240 --> 00:24:23,300 The slicing software has two main tasks. 313 00:24:23,300 --> 00:24:29,299 Firstly, it slices the object into layers. Secondly, it transfers the information to the 3D printer, 314 00:24:29,299 --> 00:24:34,590 where the extruder has to be in order to create the shape of each layer. 315 00:24:34,590 --> 00:24:39,210 For example, if you want to print a vase like the one on the left, the first layer 316 00:24:39,210 --> 00:24:43,789 would be filled completeley, because we want to fill the vase with water and it should not leak. 317 00:24:43,789 --> 00:24:48,460 The path of the extruder could look like this, it would go in rows 318 00:24:48,460 --> 00:24:52,100 from one side to the other in order to completely fill the circle. 319 00:24:52,100 --> 00:24:55,600 The second layer would be a ring and the extruder might 320 00:24:55,600 --> 00:25:00,970 take a path like this, but a different path is also possible. 321 00:25:00,970 --> 00:25:07,121 There are many different slicing programs with many setting options. 322 00:25:07,121 --> 00:25:12,539 I took a closer look and I found that the extruder 323 00:25:12,539 --> 00:25:17,820 took a very specific path for my rhomb structures. 324 00:25:17,820 --> 00:25:23,450 It went to the intersection and then turned around. Under the microscope, 325 00:25:23,450 --> 00:25:27,620 you can see that this is exactly the place where the structure was torn apart. 326 00:25:27,620 --> 00:25:33,190 The extruder did not cross the intersection even once. 327 00:25:33,190 --> 00:25:37,190 At this point, the strands of material are only connected when a new, 328 00:25:37,190 --> 00:25:40,989 hot strand melts a little bit into the other, already cold one. 329 00:25:40,989 --> 00:25:45,309 But due to the fact that the extruder did not cross the intersection, it created 330 00:25:45,309 --> 00:25:52,930 a predetermined breaking point. That is exactly where the structure was torn apart. 331 00:25:52,930 --> 00:25:57,970 In another variation that was based on the same shape, the slicing software decided 332 00:25:57,970 --> 00:26:01,960 something else. The extruder took the path to the bending point of the rhomb. 333 00:26:01,960 --> 00:26:07,490 Consequently, this is the point where it was torn apart. 334 00:26:07,490 --> 00:26:11,870 That is why the test samples look differently after the tensile test. 335 00:26:11,870 --> 00:26:18,850 That also explains the low tensile strength of the structures. 336 00:26:18,850 --> 00:26:21,932 The tensile test machine did not pull at the material as much as at these connection points 337 00:26:21,932 --> 00:26:28,340 and depending on how strong these are, 338 00:26:28,340 --> 00:26:33,549 the structure can be torn apart easily. 339 00:26:33,549 --> 00:26:37,680 This means that the method itself limits the tensile strength. 340 00:26:37,680 --> 00:26:42,809 Now, I tested eight different structures, eight different variations. 341 00:26:42,809 --> 00:26:46,309 You might ask now how I came to the conclusion that 3D printing clothes 342 00:26:46,309 --> 00:26:53,075 is not recommended in general. 343 00:26:53,075 --> 00:26:58,750 Maybe a different structure would show a higher tensile strength. 344 00:26:58,750 --> 00:27:03,610 Yes, maybe. But the method itself creates limitations concerning the properties. 345 00:27:03,610 --> 00:27:09,900 We have to go deeper and look at the molecules. 346 00:27:09,900 --> 00:27:16,581 Textile fibers naturally have a very high tensile strength. 347 00:27:16,581 --> 00:27:24,290 On the inside, natural fibers like cotton, wool or linen show a regular 348 00:27:24,290 --> 00:27:30,241 arrangement of molecular chains. 349 00:27:30,241 --> 00:27:36,300 There are amorphous parts and crystalline parts. 350 00:27:36,300 --> 00:27:42,159 The strands that you can see on the right depict molecular chains. 351 00:27:42,159 --> 00:27:46,620 The amorphous parts, where the molecules are 352 00:27:46,620 --> 00:27:51,000 tangled like a plate of spaghetti, are not stable. 353 00:27:51,000 --> 00:27:57,630 The crystalline parts, where they show a regular arrangement, are stable. 354 00:27:57,630 --> 00:28:03,862 Natural fibers show a high degree of crystalline parts which translates 355 00:28:03,862 --> 00:28:09,040 to a high tensile strength. Fibers naturally show higher tensile strengths 356 00:28:09,040 --> 00:28:13,856 than my 3D printed structures could ever have. 357 00:28:13,856 --> 00:28:17,510 And for synthetic fibers, there are measures we can take to even influence 358 00:28:17,510 --> 00:28:24,130 and increase the tensile strength. 359 00:28:24,130 --> 00:28:30,542 There are several ways to spin a fiber, at least one of them is very similar to 3D printing. 360 00:28:30,542 --> 00:28:37,400 You melt synthetic material and press it through a nozzle. 361 00:28:37,400 --> 00:28:40,978 The extruded strand is the fiber. 362 00:28:40,978 --> 00:28:45,320 The difference is that you have several possibilities to influence the property 363 00:28:45,320 --> 00:28:48,823 of the extruded strand or fiber. 364 00:28:48,823 --> 00:28:53,880 The degree of crystallinity depends on the rate of controlled cooling. 365 00:28:53,880 --> 00:28:59,750 The slower a fiber cools off the more time do the molecular chains have 366 00:28:59,750 --> 00:29:04,007 to arrange themselves regularly. 367 00:29:04,007 --> 00:29:07,850 That is why the spinning chambers are really hot 368 00:29:07,850 --> 00:29:12,690 in order to allow for a very slow rate of controlled cooling 369 00:29:12,690 --> 00:29:18,740 so that the fibers show high degrees of crystallinity, resulting in high tensile strengths. 370 00:29:18,740 --> 00:29:22,500 We do not have this opportunity in 3D printing. 371 00:29:22,500 --> 00:29:26,779 We can use a heated build plate. But that 372 00:29:26,779 --> 00:29:30,880 only influences the first few layers. 373 00:29:30,880 --> 00:29:35,299 Besides, we need the printed strands to 374 00:29:35,299 --> 00:29:40,291 cool off quickly so that they keep their shape. 375 00:29:40,291 --> 00:29:46,809 We can only print the next layer 376 00:29:46,809 --> 00:29:49,179 if the layer underneath has already hardened. 377 00:29:49,179 --> 00:29:54,159 We cannot keep a constant high temperature like we can in the spinning chamber. 378 00:29:54,159 --> 00:29:58,470 The SLS method allows for better conditions 379 00:29:58,470 --> 00:30:03,223 concerning the tensile strength 380 00:30:03,223 --> 00:30:07,150 and the structures did show better values. 381 00:30:07,150 --> 00:30:11,409 We have a second possibility to increase the tensile strength of synthetic fibers 382 00:30:11,409 --> 00:30:15,271 which is by stretching them after spinning. 383 00:30:15,271 --> 00:30:21,020 The fibers are guided through cylinders and subjected to tensile forces. 384 00:30:21,020 --> 00:30:31,460 This increases the degree of crystallinity even more. 385 00:30:31,460 --> 00:30:36,380 The molecules are forced to align even more. 386 00:30:36,380 --> 00:30:40,179 This decreases the fiber diameter and makes the fiber more fine, softer 387 00:30:40,179 --> 00:30:45,840 and at the same time stronger. 388 00:30:45,840 --> 00:30:50,700 That explains why textile fibers have much higher tensile strengths 389 00:30:50,700 --> 00:30:56,309 while at the same time being much finer than anything you can 3D print at the moment. 390 00:30:56,309 --> 00:30:59,977 Furthermore, textile fibers have the advantageous capability of warming us by isolating air. 391 00:30:59,977 --> 00:31:03,700 Every little chamber that can entrap air turns a fabric into a warming structure 392 00:31:03,700 --> 00:31:09,100 when worn on the body. Fabrics consist of threads 393 00:31:09,100 --> 00:31:13,834 and threads consist of fibers, 394 00:31:13,834 --> 00:31:18,170 as you can see on this microscope picture. 395 00:31:18,170 --> 00:31:21,559 It's not a picture of a carpet, it's fabric 396 00:31:21,559 --> 00:31:29,139 and the little single fibers would not be visible with the naked eye. 397 00:31:29,139 --> 00:31:33,779 The gaps between the fibers isolate air. 398 00:31:33,779 --> 00:31:38,000 At the same time, the gaps are important for the transportation of moisture. 399 00:31:38,000 --> 00:31:41,130 Sweat can evaporate and go through the fabric. In conclusion, 400 00:31:41,130 --> 00:31:46,220 fabrics can warm us and at the same time protect us against overheating. 401 00:31:46,220 --> 00:31:51,350 At the moment, we cannot 3D print such fine miniature fibers. We are still quite limited 402 00:31:51,350 --> 00:31:58,429 when it comes to fineness. We cannot efficiently 3D print chambers to entrap air 403 00:31:58,429 --> 00:32:04,059 like the ones we can find in fabrics made of textile fibers. 404 00:32:04,059 --> 00:32:08,970 Some things cannot be done yet in 3D printing. But what can we do 405 00:32:08,970 --> 00:32:15,220 in 3D printing instead? We have an immense freedom of design that can be applied 406 00:32:15,220 --> 00:32:20,679 mostly in shoes and accessories, 407 00:32:20,679 --> 00:32:24,649 for example bracelets, necklaces or glasses. 408 00:32:24,649 --> 00:32:29,450 The benefits can be used for costumes. 409 00:32:29,450 --> 00:32:34,998 For example, in the movie "Black Panther", several crowns were 3D printed. 410 00:32:34,998 --> 00:32:39,520 Theoretically, the process is sustainable, 411 00:32:39,520 --> 00:32:44,076 just because it is additive manufacturing. 412 00:32:44,076 --> 00:32:48,059 Material is only built where it is needed for the desired shape. 413 00:32:48,059 --> 00:32:53,909 This is in stark contrast to the production of clothes. 414 00:32:53,909 --> 00:32:58,620 When you cut the fabric, you can achieve a utilization ratio of maybe 90%. 415 00:32:58,620 --> 00:33:03,262 Just because pattern pieces have many different shapes, 416 00:33:03,262 --> 00:33:07,280 10% of the fabric is thrown away. 417 00:33:07,280 --> 00:33:15,017 3D printing is more sustainable in this aspect. 418 00:33:15,017 --> 00:33:17,899 Also, the materials can be reused. 419 00:33:17,899 --> 00:33:20,870 Recycling is another problem in the fashion industry. 420 00:33:20,870 --> 00:33:24,440 So it is a good thing that you can reuse the powder after printing. 421 00:33:24,440 --> 00:33:30,270 3D printing is also very suitable for made-to-order production. 422 00:33:30,270 --> 00:33:34,530 In the fashion industry, made-to-order items always lead to high costs. 423 00:33:34,530 --> 00:33:38,909 Also, it is possible to create different material properties in the same product. 424 00:33:38,909 --> 00:33:42,764 When I have the shoulder 425 00:33:42,764 --> 00:33:47,279 and want it to be a bit more firm, 426 00:33:47,279 --> 00:33:50,797 I can already prepare that in the 3D model. I can decide 427 00:33:50,797 --> 00:33:54,620 to create more layers. If I created the same piece of clothing in fabric, 428 00:33:54,620 --> 00:33:58,320 I would need to have a seam, I would reinforce it with another fabric 429 00:33:58,320 --> 00:34:02,440 or another layer of fabric. Using a 3D printer, this could happen in the same step. 430 00:34:02,440 --> 00:34:07,050 Theoretically, it is also possible to integrate additional functions 431 00:34:07,050 --> 00:34:13,290 like cables, LED or sensors. 432 00:34:13,290 --> 00:34:18,440 There is still a question mark behind that. 433 00:34:18,440 --> 00:34:22,530 First of all, this would not be everyday wear, 434 00:34:22,530 --> 00:34:28,790 and secondly, this is not state of the art yet. 435 00:34:28,790 --> 00:34:33,170 Another benefit might be to create the whole garment in one step. 436 00:34:33,170 --> 00:34:36,769 Right now, a fabric is created out of threads out of textile fibers. 437 00:34:36,769 --> 00:34:39,330 Then, the fabric needs to be cut, the pieces need to be sewn together, 438 00:34:39,330 --> 00:34:42,070 maybe it is dyed after that. Different processes, 439 00:34:42,070 --> 00:34:46,370 executed at different locations. With 3D printing, 440 00:34:46,370 --> 00:34:52,090 everything could happen in the same step. 441 00:34:52,090 --> 00:34:56,118 But only if the garment can fit into the build volume of a printer. 442 00:34:56,118 --> 00:35:00,230 If we print A4 sized pieces and assemble them afterwards, 443 00:35:00,230 --> 00:35:04,550 we are still in the same situation of having to connect many pieces. 444 00:35:04,550 --> 00:35:11,230 The software developed by Nervous System is a smarter solution. 445 00:35:11,230 --> 00:35:15,286 The software digitally folds the dress. The dress is then printed in the folded state, 446 00:35:15,286 --> 00:35:20,030 significantly reducing the needed build volume. 447 00:35:20,030 --> 00:35:25,960 The dress is hidden somewhere in the block of powder. 448 00:35:25,960 --> 00:35:29,810 The powder is removed, a bit like in archeology, 449 00:35:29,810 --> 00:35:34,094 the dress will get cleaned off and opened. 450 00:35:34,094 --> 00:35:37,411 This is a good option to really use the benefits of 3D printing. 451 00:35:37,411 --> 00:35:46,520 The disadvantages or challenges are 452 00:35:46,520 --> 00:35:51,190 the insufficient tensile strength, resulting from the process itself 453 00:35:51,190 --> 00:35:56,180 and there is not a lot we can do about it. We are still very limited 454 00:35:56,180 --> 00:36:03,340 in terms of fineness. The standard nozzle diameter is 0.4 millimeters. 455 00:36:03,340 --> 00:36:08,695 Fiber diameters are more in the micrometer range. 456 00:36:08,695 --> 00:36:13,556 That is a significant difference. The fineness is very important for the next-to-skin-comfort, 457 00:36:13,556 --> 00:36:17,920 for the transportation of moisture and for the capability to warm us. 458 00:36:17,920 --> 00:36:24,720 This is fundamental and without it, the aspects of wearing comfort 459 00:36:24,720 --> 00:36:31,258 cannot be guaranteed when we 3D print textile structures. 460 00:36:31,258 --> 00:36:36,119 Time and costs are still quite problematic in 3D printing. 461 00:36:36,119 --> 00:36:40,650 It takes af long time and it is very expensive. 462 00:36:40,650 --> 00:36:45,095 Again, this is not suitable for everyday wear, only for individual pieces. 463 00:36:45,095 --> 00:36:48,014 We also still have to discuss care instructions. 464 00:36:48,014 --> 00:36:51,378 Can you wash a 3D printed garment at all? If I wear a piece of clothing every day, 465 00:36:51,378 --> 00:36:54,589 I want to be able to wash it. 466 00:36:54,589 --> 00:36:58,082 When we talk about garments, we also need to talk about fastenings, 467 00:36:58,082 --> 00:37:02,144 you need to somehow get inside the piece of clothing. 468 00:37:02,144 --> 00:37:06,251 So, zippers, buttons, hooks, eyelets, all of this needs to be thought of 469 00:37:06,251 --> 00:37:12,750 if we want to print everything in one piece. 470 00:37:12,750 --> 00:37:17,090 In conclusion, the construction of fabrics made from threads made from fibers 471 00:37:17,090 --> 00:37:23,170 is still unbeatable in regards of wearing comfort. 472 00:37:23,170 --> 00:37:28,379 There are not yet applicable solutions 473 00:37:28,379 --> 00:37:40,370 to imitate the properties in 3D printing. 474 00:37:40,370 --> 00:37:44,478 At the current state of the art, 3D printed clothes are not only not the future, 475 00:37:44,478 --> 00:37:47,257 they aren't even the present. Because the present means 476 00:37:47,257 --> 00:37:50,930 fabrics made of textile fibers and that works really well for our wearing comfort. 477 00:37:50,930 --> 00:37:55,430 3D printed structure cannot provide that yet. 478 00:37:55,430 --> 00:37:58,660 That does not mean that we should stop the research. 479 00:37:58,660 --> 00:38:01,260 Whoever said before that they had success when printing clothes, 480 00:38:01,260 --> 00:38:04,760 I am very interested to hear about that. Maybe there are some aspects 481 00:38:04,760 --> 00:38:11,587 that I have not thought about. But we should not forget 482 00:38:11,587 --> 00:38:17,460 the basic function of clothes. The 3D printed clothes that I showed in the beginning, 483 00:38:17,460 --> 00:38:21,800 those are amazing artworks, I love them and I want to see more of them. 484 00:38:21,800 --> 00:38:24,820 But I want to remind everyone that clothes should warm us, 485 00:38:24,820 --> 00:38:28,170 that in general, it should be opaque and that the climate exchange 486 00:38:28,170 --> 00:38:33,840 and the transportation of moisture has to be guaranteed. I find it a bit difficult 487 00:38:33,840 --> 00:38:38,370 to put so much hope on 3D printing 488 00:38:38,370 --> 00:38:44,030 to fundamentally change the whole fashion industry. 489 00:38:44,030 --> 00:38:49,371 Because the fashion industry has a lot of serious problems, 490 00:38:49,371 --> 00:38:53,580 ecological problems, 491 00:38:53,580 --> 00:38:57,250 but also social and societal problems. 492 00:38:57,250 --> 00:39:01,229 But I don't think we should simply hope to develop new technologies 493 00:39:01,229 --> 00:39:04,440 and tell us that the sustainability problem can be solved by 3D printing 494 00:39:04,440 --> 00:39:09,850 all of our clothes. Please conduct further research. 495 00:39:09,850 --> 00:39:15,830 But please don't forget the basic functions of clothes and do not think 496 00:39:15,830 --> 00:39:20,323 that a new technology will solve all the problems of the fashion industry. 497 00:39:20,323 --> 00:39:27,140 I advise everyone to revolutionize the fashion industry. 498 00:39:27,140 --> 00:39:32,650 But please do not think that 3D printing is the universal solution for that. 499 00:39:32,650 --> 00:39:36,782 And now I am finished with my presentation and I thank you all for listening. 500 00:39:36,782 --> 00:39:47,155 *applause* 501 00:39:47,155 --> 00:39:49,912 Herald Angel Noujoum: Yes, thank you, that was quite a precision landing, I'm afraid 502 00:39:49,912 --> 00:39:52,830 we don't have time left for questions, I am sorry to everyone flocking to the microphones right now. 503 00:39:52,830 --> 00:39:57,330 But you can see here where you can talk to Rebekka, 504 00:39:57,330 --> 00:40:01,409 you can find her and ask her questions on Twitter under @Kurfuerstin. 505 00:40:01,409 --> 00:40:04,331 You can also talk to her right now after the talk. Maybe not right here, 506 00:40:04,331 --> 00:40:07,330 but somewhere in the back. She also needs to read her post cards. 507 00:40:07,330 --> 00:40:10,780 I'm sure there will be time and the possibility 508 00:40:10,780 --> 00:40:14,600 to talk to her or each other about 3D printing and 3D printed clothes. 509 00:40:14,600 --> 00:40:17,556 Please give another round of applause. 510 00:40:17,556 --> 00:40:18,670 *applause* 511 00:40:18,670 --> 00:40:22,280 *postroll music* 512 00:40:22,280 --> 00:40:30,234 Subtitles created by c3subtitles.de in 2020. Join us!