added bacterial dye

docs/assignments/week04.md

@@ -11,9 +11,9 @@ The students in the Amsterdam lab collaborated to make a shared repository of dy
 ![](../images/wk04_collage.jpg)*A love affair with cabbage, Loes Bogers 2019*
 
 **Dying silk with bacteria**<br>
-And lastly, dyed a piece of silk using Serratia Marcensis grown and nurtured by Cecilia and her collaborators at the Biolab. We cooked the growing medium together, sterilized together and each dyed our own piece of silk: 
+And lastly, dyed a piece of silk using Serratia marcenscens grown and nurtured by Cecilia and her collaborators at the Biolab. We cooked the growing medium together, sterilized together and each dyed our own piece of silk: 
 
-![](../images/wk04_bacteriasilk2.jpg)*Silk died with Serratia Marcensis, Loes Bogers 2019*
+![](../images/wk04_bacteriasilk2.jpg)*Silk died with Serratia marcenscens, Loes Bogers 2019*
 
 **Inks**<br>
 We made a range of inks based on the dye recipes (some modified, others not) and experimented with it on paper, using several modifiers. 
@@ -242,10 +242,10 @@ Once you start working with the bacteria themselves: close doors and windows to
 
 Sign in and out and clean up your dishes. Through away the water after. 
 
-###Meeting Serratia Marcensis
-We met Serratia Marcensis! A red/orange beauty that gives us pink (in acidic solutions) if you treat her well and feed her peanut butter. They used to keep a purple one too but sadly it died when the freezer broke over summer. You have to keep her alive by giving her new food every few days (replating). 
+###Meeting Serratia marcenscens
+We met Serratia marcenscens! A red/orange beauty that gives us pink (in acidic solutions) if you treat her well and feed her peanut butter. They used to keep a purple one too but sadly it died when the freezer broke over summer. You have to keep her alive by giving her new food every few days (replating). 
 
-![](../images/wk04_thebacteria.jpg)*Serratia Marcensis at the biolab, Loes Bogers, 2019*
+![](../images/wk04_thebacteria.jpg)*Serratia marcenscens at the biolab, Loes Bogers, 2019*
 
 ###Growing media, or: what to feed Serratia
 Plate some growing media mixed with crunchy(!) peanut butter. Nuts and seeds can do wonders with some bacteria. We prepared these growing media: 
@@ -267,8 +267,8 @@ We measure the ingredients with a precision scale (stabilize before using), by p
 
 Then we sterilized the food bottles. The lid should be loose! Otherwise it can explode in the pressure cooker. You close them after sterilizing. 
 
-*Autokleeftape!*
-Stick a bit of autokleeftape to the top. It has diagonal lines that turn dark if you sterilized correctly. Handy....
+*Autoclave tape!*
+Stick a bit of autoclave tape to the top. It has diagonal lines that turn dark if you sterilized correctly. Handy....
 
 *Handling the pressure cooker*
 Close the lid, seal the lid (locking it), and turn the knob to position 2. When the little pin firmly comes *all the way out*, the cooker is under pressure and you can start the timer for 15 mins.
@@ -281,7 +281,7 @@ We each got a piece of silk that we folded or crumpled up to create patterns/sym
 
 ![](../images/wk04_folding.gif)<br>*My folding improvisation, Loes Bogers, 2019*
 
-Put the fabrics in **glass petri dishes**, or in a heat-resistant **autoplate bag**. Again, stick some autokleeftape on to assess whether it sterilized correctly. Sterilize for at least 15 mins under pressure in the pressure cooker. 
+Put the fabrics in **glass petri dishes**, or in a heat-resistant **autoclave bag**. Again, stick some autokleeftape on to assess whether it sterilized correctly. Sterilize for at least 15 mins under pressure in the pressure cooker. 
 
 ###Plating
 

docs/files/ingredients/linseedoil.md

@@ -9,7 +9,8 @@ See more at: https://www.tradextra.co.nz/raw-or-boiled/
 
 https://en.wikipedia.org/wiki/Linseed_oil#Wood_finish
 
-Raw raw raw
+boiled is cheaper say the kombucha guys, but try it out
+
 just be patient
 
 Or boiled????? 

docs/files/recipes/cabbagedye.md

@@ -93,7 +93,7 @@ Approx. 250 ml
 - Add a binder such as arabic gum to create a nicer flow if you wish to use this ink for painting and arts, not dyeing textiles.
 - Instead of making a water-based ink, you can also use red cabbage to make an alcohol-based marker ink. Grate the cabbage and chop as finely as possible, cover with denatured alcohol 96% and put in a jar with a tightly fitting lid. Shake every hour for 24 hours. Strain the liquid, add a clove, label and store. The ink can be modified with PH modifiers as well but this ink fades quicker than the dye. 
 - You can even use red cabbage dye to test the PH of a liquid. Dip some strips of coffee filter in the red cabbage dye. Let it dry. Then use a cotton swab to dab a bit of liquid (tap water, juice, wine, other) on the paper. If the paper becomes red/pink the PH is 2-4, purple is 5-7, blue is 8-9 and green/yellow is PH 10-12 approximately. See also [link](https://www.thoughtco.com/make-red-cabbage-ph-paper-605993)
-- Make dyes for other kinds of food waste, like used coffee grounds (light browns), old coffee (deep browns), PH sensitive beetroot dye (vintage pinks and salmon tones) etc. Or research and consider dyes from dried goods like turmeric powder (bright yellow), PH sensitive hibiscus tea (purple, blues, greens and gray). 
+- Make dyes for other kinds of food waste, like used coffee grounds (light browns), old coffee (deep browns), PH sensitive beetroot dye (vintage pinks and salmon tones) etc. Or research and consider dyes from dried goods like turmeric powder (bright yellow), PH sensitive hibiscus tea (purple, blues, greens and gray). Ink has even been made of cigarette butts!
 
 ### Cultural origins of this recipe
 
@@ -175,6 +175,7 @@ Yes
 - **Make Red Cabbage PH Paper** by Anne Marie Helmenstine for ThoughtCo, 2 February 2020: [link](https://www.thoughtco.com/make-red-cabbage-ph-paper-605993)
 - **Biochromes** by Cecilia Raspanti for Fabricademy, 15 October 2019: [link](https://class.textile-academy.org/classes/week04/)
 - **Purple** in: The Secret Lives of Color by Kassia St. Clair, 2016: pp. 159-161.
+- **Make Ink** by: Jason Logan, 2018.
 
 ### Images of final product
 

docs/files/recipes/fishskin.md

@@ -124,7 +124,7 @@ Not sure
 - Add natural *alcohol-based* colorants to dye the fish skins (e.g. turmeric, hibiscus, or grated beetroot/red cabbage: submerge in alcohol and shake every hour for a day).
 - Other softeners to try: leather balm, coconut oil, other oils
 - Putting a fish skin in the oven for 5-10 minutes at low heat (70 degrees Celcius), it turns highly flexible.
--  Make a suede-like soft leather by tanning the fish skins in raw linseed oil. Add a rock or something heavy to create a lot of friction when shaking the container. Take the fish out to dry, repeat if it is not soft enough. There are several linseed oils out there. Raw is often used for outdoors use and contains less chemicals and petrol-based drying agents but dries a lot slower and can stay sticky. This technique is similar to they way fishing nets are impregnated to stand the harsh conditions at sea. 
+-  Make a suede-like soft leather by tanning the fish skins in boiled linseed oil. Add a rock or something heavy to create a lot of friction when shaking the container. Take the fish out to dry, repeat if it is not soft enough. There are several linseed oils out there. Raw is often used for outdoors use and contains less chemicals and petrol-based drying agents but dries a lot slower and can stay sticky. The technique used with raw linseed oil is similar to they way fishing nets are impregnated to stand the harsh conditions at sea. 
 
 ### Cultural origins of this recipe
 

docs/files/recipes/kombuchapaper.md

@@ -29,7 +29,7 @@ Final form achieved after: 5 days
 * **Kombucha SCOBY** - 1 piece of 2-3 mm thickness, grow one with [this recipe](https://class.textile-academy.org/2020/loes.bogers/files/recipes/kombuchascoby)
 * **Turpentine** - 1 tbsp (15 ml) + a little more
 * **Beeswax, melted** - 1 tbsp (15 ml)
-* **Raw Linseed/Flax oil** - 1 tbsp (15 ml) you can get this at a hardware story, this is not the same as the food-grade one from the supermarket.
+* **Boiled Linseed/Flax oil** - 1 tbsp (15 ml) you can get this at a hardware story, this is not the same as the food-grade one from the supermarket.
 
 
 ## Tools

docs/files/recipes/madderdye.md

@@ -94,7 +94,9 @@ Approx. 500 ml
 
 ### Cultural origins of this recipe
 
-Before synthetic dyes were discovered in 1856, you would have had to use natural dyes which were made from animals and plants. The most common - and intense -  being madder, red, and indigo, blue. Madder came from the roots of 35 species of plants (Rubia Tinctorum) found in Southern Europe and West-Asia. It has been found in the cloth of mummies and was the first dye to be used as camouflage. Madder was brought to the south of the Netherlands and Flanders around 1300 where the soil was optimal for madder cultivation. This led to a thriving local industry for madder production, until *garancine* the synthetic counterpart for alizerine was discovered and gained in popularity around 1870. The agricultural industry of madder plants has started growing again in Belgium and the Netherlands in recent years as the textile and fashion industry started rediscovering its potential as a natural pigment for textile dyeing. 
+Before synthetic dyes were discovered in 1856, you would have had to use natural dyes which were made from animals and plants. The most common - and intense -  being madder for red, and indigo for blue. Madder came from the roots of 35 species of plants (Rubia Tinctorum) found in Southern Europe and West-Asia. It has been found in the cloth of mummies and was the first dye to be used as camouflage. It was a popular dye madder in the Middle Ages and is mentioned in the Plichto van Gianventura Rosetti from 1548. Madder was brought to the south of the Netherlands and Flanders around 1300 where the clay soil was optimal for madder cultivation. This led to a thriving local industry - and for a while a monopoly - for madder production (NL: "meekrap") deemed the best quality in Europe .This was the case until *garancine* the synthetic counterpart for alizerine was discovered and gained in popularity around 1870. 
+
+The agricultural industry of madder plants has started growing again recently in Belgium and the Netherlands since experiments in Groningen from 1989 onwards. In 1999 a technique was discovered to create powdered pigment from the roots that is viable for the industry. The textile and fashion industry started rediscovering its potential as a natural pigment for textile dyeing. Its yellow and blue counterparts have also been developed from "wouw" (Reseda lutolea L.) in other parts of Europe and the cultivation of "wede" (Isatis tinctoria L.) in France.
 
 **Needs further research?**   Not sure
 
@@ -105,10 +107,12 @@ Before synthetic dyes were discovered in 1856, you would have had to use natural
 
 ### Known concerns and contestations
 
-Compared to red pigments coming from the synthetic garancine, madder is less ecologically taxing. It doesn't require the sulphuric acid was used in the synthetic product. The plant can easily be multiplied and can be harvested after 2-3 years but is deemed rather labour intensive (require a fair amount of weeding and fertilizing). The roots need to be dried, which happens naturallly in sun light in warme climates. Heat needs to be generated in cold areas such as northern Europe. In comparison to commercial synthetic dyes, it is surely an improvement. 
+Compared to red pigments coming from the synthetic garancine, madder is less ecologically taxing. It doesn't require the sulphuric acid was used in the synthetic product. The plant can easily be multiplied and can be harvested for dyeing only after 2-3 years. The process is deemed rather labour intensive (require a fair amount of weeding and fertilizing). The roots need to be dried, which happens naturallly in sun light in warme climates. Heat needs to be generated in cold areas such as northern Europe. In comparison to commercial synthetic dyes, it is surely an improvement. 
 
 Intense colors can be considered a thing of great luxury. To create very concentrated inks and dyes, one needs a lot of dye stuff and additional compounds like alum and soda for intensification. Although sulphuric acids are left out of this recipe, could and should we not consider deep, concentrated dyes as a thing of luxury, not necessity? How might beauty be found in more subtle hues? Could we consider limiting ourselves to pigments extracted from e.g. food waste like avocado stones, onion skins or leftover red cabbage?
 
+As far as natural dyes go, madder is one that has been developed to a little that is applicable in the dyeing industry, not just crafts dyeing. Rubia Pigmenta Naturalia is a powdered form of meekrap pigment that is suitable for most industrial settings. 
+
 Needs further research: Madder traveling from other parts of Europe and Asia to Northern Europe is possibly tied to practices of colonization and/or warfare. 
 
 ### Sustainability tags
@@ -131,11 +135,12 @@ This dye gives a bright red on silk. And pink/salmon tones on paper.
 
 ### Technical and sensory properties
 
-- **Color fastness:** medium
-- **Light fastness:** medium
-- **Washability:** medium
-- **Color modifiers:** alkaline/acidic/copper/iron
+- **Color fastness:** high, it is traditionally called a "grande teint" for this reason
+- **Light fastness:** high
+- **Washability:** high
+- **Color modifiers:** acidic/alkaline
 - **Odor**: moderate
+- **Suitable fibres**: animal fibre like wool or silk will take better than cellulose fibres. Use of alum as mordant is recommended for intense reds.  Synthetic fibres won't take on this dye. 
 
 ## About this entry
 
@@ -180,6 +185,9 @@ Yes, this is an adaptation of the recipes listed in the references but there are
 - **Meekrap**, Dutch page for "madder" on Wikipedia, n.d. [link](https://nl.wikipedia.org/wiki/Meekrap)
 - **Meekrap**, by Jan Zwemer for Zeeuwse Ankers, n.d. [link] (https://www.zeeuwseankers.nl//app/uploads/2018/07/Meekrapteelt-en-bewerking.pdf)
 - **A brief history of natural dyes**, by James P. Bernard for First Source Worldwide, 14 November 2017, [link](http://www.fsw.cc/NATURAL-DYES-HISTORY/)
+- **Natuurlijk Verven, Grand Teints**, by Jantine Koobs for Textiel Museum, Tilburg, 2017: [link](https://textielmuseum.nl/uploads/content/BTME001.pdf).
+- **Natuurlijk verven: textielverven op ecologische wijze**, by Roos Soetekauw, Thesis about natural dyes and dying of wool and silk, 2 May 2011:
+ [link](https://issuu.com/roossoetekouw/docs/scriptie_-_natuurlijk_verven_klein)
 
 ### Images of final product
 
@@ -190,3 +198,4 @@ Yes, this is an adaptation of the recipes listed in the references but there are
 ![](../../images/finalpics-89.jpg)*Madder dye on paper, Loes Bogers, 2020*
 
 
+

docs/files/recipes/phmodifiers.md

-# PH MODIFIERS FOR BIOCHROMES
+# PH MODIFIERS & PH PAPER
 
-### Tactility & sound impression
-
-<iframe width="560" height="315" src="https://www.youtube.com/embed/gNOtGunJc2A" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>
+##MAKE PH 2, 5, 9 and 13
+##FINAL PICS
+##EXACT MEASUREMENTS
+##PRICE
 
 ### Description
 
-A (naturally) amber-coloured hard bioresin, gelatin-based.
+Recipe for an alkaline (PH13) and an acidic (PH2) PH modifier to be used with natural dyes and inks (water and alcohol-based). These can change the original color to become brighter, duller, or even go all the way from purples to greens and blues. Alkaline tends to make colors "colder", while acidic dyes create warmer shades. Acidic and alkaline modifiers have an especially strong effect on dyes made of vegetables that contain anthocyanin such as red cabbage dye, hibiscus, blueberry. 
 
 ### Physical form
 
-Solids
+Pastes, gels & liquids
 
-Color without additives: transparent, yellow/orange/amber colored.
+Color without additives: Transparent colorless. Can take on some pigments if dyed textile is dipped in.
 
 ### Fabrication time
 
-Preparation time: 1 Hour
+Preparation time: 10 minutes
 
-Processing time: 5-10 days
+Processing time: N/A
 
-Need attention: None, just leave it to dry as long as is feasible with lots of airflow.
+Need attention: N/A
 
-Final form achieved after: 10 days
+Final form achieved after: N/A
 
 ## Ingredients
 
-* **Gelatine powder - 96 gr**
-	* Functions as the polymeer (so it becomes a solid)
-* **Glycerine - 16 gr**
-	* Functions as plasticizer that bonds with the gelatine (makes it flexible). 
-* **Water - 480 ml/gr**
-	* To dissolve and mix the polymeer and plasticizer
+* **Water - 800 ml**, the solvent, ideally has a PH of 7.
+* **Soda ash - up to 50 g**, to make an alkaline solution (PH 8-PH 13)
+* **Citric acid - up to 50g** OR: 150 ml of vinegar or lemon juice, to make an acidic solution (PH 1 -PH 6). Citric acid is sold in asian supermarket and has very high acidity (more than vinegar and lemon juice)
+* **Red cabage dye - 50 ml** see [this recipe](https://class.textile-academy.org/2020/loes.bogers/files/recipes/cabbagedye/). Alcohol-based cabage ink is also fine. 
+* **A large round coffee filter**, ideally white ones. To make PH strips. If you can't find these, get 4 smaller filters and cut them open so you have only one layer. 
 
 ## Tools
 
-1. **Cooker or stove** (optional: temperature controlled)
-1. **Pot**
-1. **Scale**
-1. **Moulds** (ideally with removeable base to increase airflow). I have modular silicon walls with metal wire inside them that allow me to cast and then turn the moulds on their side for more airflow and drying from top and bottom. I use a silicon or acrylic sheet with these mould walls.
-1. **Spoon** 
+1. **Four glass jars** size depending on how much PH modifying solution you wish to prepare, 200 ml and up is convenient for dipping dyed textile swatches. 
+1. **A spray bottle - approx 100 ml** 
+1. **A small funnel** that fits the spray bottles
+1. **A baking tray or acrylic sheet** to dry the PH paper
+1. **Commercial PH measuring strips** or a PH measuring device
+1. **A stapler, or some paperclips, or sticky tape** 
 
 
 ## Yield before processing/drying/curing
 
-Approx. 300 ml (make sure to evaporate a lot of water during cooking time)
+Approx. 200 ml of each and 60-100 PH strips.
 
 ## Method
 
-1. **Preparation**
-
-	- Weigh your ingredients
-	- Prepare the mold and find a place where you can leave it for a while, ideally near an open window where there's air flow.
-
-1. **Mixing and dissolving the ingredients**
-	- bring the water to the boil
-	- optional: add natural dye if you wish to use color
-	- add the glycerine
-	- add the gelatine
-	- keep the temperature below 80 degrees celcius while stirring *very very slowly and gently* to avoid making bubbles. I prefer a simple spoon to do this, not a whisk.
-
-1. **Cooking the ingredients**
-
-	- 	Simmer and slowly stir the mixture between 60-80 degrees celcius for at least 20 minutes or up to an hour. Turn it lower when bubbles appear: you don't want the liquid to move, don't boil it. This sample has some bubbles due to vigorous mixing.
-	-  Longer cooking time allows more water to evaporate. You will get a thicker liquid. To cast larger volumes and solids with this recipe, evaporate a lot of water, until it's very thick.
-	
-1. **Casting**
-
-	- 	Let the liquid cool for a couple minutes until it gels a little but is still liquid and pourable.
-	-  Cast into the mould slowly to avoid bubbles
-	-  Pour from the middle and hold still, let the liquid distribute itself.
-	-  Put the mould away to dry in a cool place with lots of air flow (like near an open window). A warmer place might speed up the drying process but also allow bacteria to grow faster and can result in fungal growth.
-	-  If the mould has a removable base, remove it after 4-8 hours and put the mould on its side to allow air flow from both sides. 
-	-  When using a flexible mould: let it dry without releasing to keep the form as much as possible. The resin will likely shrink and release itself from the mold. If it feels cold to the touch it is still drying. If you are using a rigid mold: release after 4-8 hours and dry flat.
-
-
-### Drying/curing/growth process
-
-- Mold depth:  				 7 cm (filled up until 2.5cm high)
-- Shrinkage thickness:      20-30 %
-- Shrinkage width/length:   20-30 %
-
-**Shrinkage and deformation control**
-
-Letting it dry up to ten days to get to the final form. It will be flexible at first but will slowly harden until its totally rigid.
-
-**Curing agents and release agents**
-
-None. 
-
-**Minimum wait time before releasing from mold**
-
-Using a silicon mold: 7 days (or until it comes undone)
-
-**Post-processing**
-
-Store in a dry and ventilated room.
-
-**Further research needed on drying/curing/growth?**
-
-Casting larger volumes without growing fungus/mold, and limited warping can be challenging. Fillers like debris or egg shells can help. More research can be done on ideal conditions for drying larger volumes.
-
-The resin does not cure evenly across the surface, some might be negotiated by shaving off some slides while it is still relatively soft and flexible.
+1. **Preparing the PH paper**
+
+	- Put the cabbage dye in one of the spray bottles
+	- Clean and thoroughly dry the drying surface (e.g. baking tray) to prevent staining.
+	- Put the coffee filter on the baking tray/sheet
+	- Spray the coffee filter with the cabbage dye until it is totally covered (one side only). 
+	- Lay it flat and let it dry completely
+	- Empty and wash the spray bottle.  
+
+1. **Making the alkaline PH modifiers**
+	- Boil the water and divide it over two glass jars
+	- Add half a teaspoon of soda ash to one, and stir to dissolve. 
+	- Dip a piece of PH paper in to test the PH
+	- If it is higher than 7 your solution is alkaline. Bring the PH up to PH 9, this is a good starting entry point to modify dyes and inks with. 
+	- Do the same with the other jar but take the PH all the way up to PH 13, this can modify your dyes severely so take it step by step to see all the hues you can create. 
+	- Label the solution, mentioning the PH value and store in the glass jar or in a spray bottle.
+
+1. **Making the acidic PH modifier**
+	- Boil the rest of the water and divide it over two glass jars
+	- Add half a teaspoon of citric acid to one, and stir to dissolve. 
+	- Dip a piece of PH paper in to test the PH
+	- If it is lower than 7 your solution is turning acidic. Bring the PH down to 5 by adding little bits of citric acid. 
+	- Do the same with the other jar but bring the PH all the way down to PH 2, this can modify some dyes severely. 
+	- **NOTE**: if you don't have citric acid, you can work with lemon juice or vinegar but these are weaker acids. So work in the opposite order: put some vinegar/lemon juice in the jar, measure the PH and add a bit of water to bring the PH value up. 
+
+1. **Cut a PH paper booklet**
+	- When the coffee filters are totally dry, take them off the tray and fold them 3 times. 
+	- Fold the sharp tip inward and secure with a paperclip, or staple, or sticky tape. 
+	- Cut the closed fold open to separate the sheets
+	- Cut parallel lines into the stack of sheets (not all the way), to create strips you can tear off easily
+
+1. **Make a legend for your PH paper**
+	- Tear 5 pieces off of your PH paper
+	- Dip them in each of your PH modifiers, and dip one in tap water
+	- Make sure they don't touch each other or lie in each others liquids. 
+	- Let them dry and write on them the PH value of the modifier they were dipped into. 
+	- Stick, glue or staple them on a piece of paper you can keep with your PH paper as reference. 
+
+1. **Using PH modifiers**
+	- Add the modifier directly to the dye to modify the entire batch (not recommended)
+	- Modify the dyed/stained material afterwards by dipping it into the modifier, spraying it on, or in some cases for textiles: let it simmer for 10 minutes on low heat. 
+	- You can use both modifiers at the same time to create colorful patterns and stains. 
+	- Some dyes allow you to go back and forth with the modifiers, but they will likely change if you modify them with PH 2 first and then bring it up to PH13, this could create hues than cannot be created using only one modifier. 
+	- Dyes that already have an alkaline additive (like soda) or an acidic additive (like vinegar) are unlikely to respond strongly to the same modifier. 
+
+1. **Using the PH paper**
+	- Use the PH paper to test the PH value of dyes, solutions and even bioplastics mixtures. 
+	- It is useful to know and record this information. For example, if a bioplastics mixture is very acidic (e.g. the starch-based plastics that contain vinegar), it will modify the color of a PH sensitive dye when you add it. Knowing this before hand will help you pick your dyes accordingly. 
+	- Also testing the PH values of water can be useful. In some recipes you might need to know if your tap water is alkaline or not so you can assess whether you need to offset it by adding some vinegar or other acid to your recipe (e.g. for growing kombucha SCOBY).  
 
 
 ### Process
 
-![](../../images/resin5a.jpg)*Evaporating water until the liquid is thick like honey, Loes Bogers, 2020*
-
-![](../../images/resin5.jpg)*Preparing molds for small half domes (egg cups), and a big slab (silicon mould and separate base), Loes Bogers, 2020*
+![](../../images/phpaper13.jpg)*The cabbage dye on a coffee filter, drying, Loes Bogers, 2020*
 
-![](../../images/resin6.jpg)*Casting the resin (I had to put a weight on top to press the mold into the base and prevent leakage, Loes Bogers, 2020*
+![](../../images/phpaper11.jpg)*Folding the paper, Loes Bogers, 2020*
 
-![](../../images/resin8.jpg)*Putting the mold on its side next to open window to allow further drying from top and bottom, Loes Bogers, 2020*
+![](../../images/phpaper10.jpg)*Securing and cutting the paper, Loes Bogers, 2020*
 
+![](../../images/phpaper9.jpg)*Cutting tear-off strips, Loes Bogers, 2020*
 
 ## Variations on this recipe
 
-- Add a **natural colorant** such as a vegetable dye or water-based ink (e.g. hibiscus, beetroot, madder)
-- Add **less glycerine** for a more rigid foil
-- **Stiffeners** such as fibres, yarn or natural debris may be added for more structure and reinforcement.
-- **Fillers** such as almond or sunflower oil, can be added to prevent additional shrinkage but might affect stickyness.
+- Make a better design for the booklet, without wasting material.
+- Experiment by combining PH modifiers with traditional tie-dyeing and printmaking techniques.
+- Experiment by using the water-based dyes to stain paper and modify then while wet for organic water colors-like effects, or dry for clear, sharp contrasting colors. 
+- Research other foods that contain anthocyanin and make paper with juice and dyes from other fruits and vegetable waste.
 
 ### Cultural origins of this recipe
 
-Bioplastic production is older than petrol based plastics. In 1500 BC, people in Egypt were already using glues based on gelatin, casein and albumin for furniture constructions. Gelatin casting as a technique has also been used in production of jelly-based foods such as aspic, jelly desserts and candy.
-
-**Needs further research?**   Not sure
+Red cabbage juice has been known to be a PH indicator (origins unknown) and is a favourite for science experiments in education. 
 
-### References this recipe draws from
+A historically more well-known PH indicator however, is the *litmus test*, a procedure ascribed to Spanish alchemist, astrologer and phycisian Arnaldus de Villa Nova, around 1300. The term litmus comes from an Old Norse word meaning "to dye or color." As such it is strongly associated with practices of alchemy, a precursor to contemporary science that has long been ridiculed for its esoteric philosophy, magic and quest to turn lead into gold. Eventually historians of science acknowledged alchemy for laying groundwork for science with many of its practical and experimental applications and techniques, such as litmus.
 
-- **Bioresin (gelatin) Recipe** by Cecilia Raspanti (Textile Lab, Waag), Fabricademy Class "Biofabricating", 2019, [link](https://class.textile-academy.org/classes/week05A/).
-- **The Bioplastics Cookbook: A Catalogue of Bioplastics Recipes** by Margaret Dunne for Fabtextiles, 2018, [link](https://issuu.com/nat_arc/docs/bioplastic_cook_book_3) 
+Litmus paper and universal PH scale is said to have been invented by J.L. Gay-Lussac in the early 1800s. The blue dye used for litmus paper was extracted from lichens (various types could be used for this and they grow in nearly every climate). The Netherlands was and is to this day a primary producer of litmus paper, using the local lichens variety called *lecanora tartarea*. Interestingly, lichens are commonly used as gauge for environmental quality because they are sensitive to various pollutants.
 
-### Known concerns and contestations\*
+**Needs further research?**   Not sure
 
-Needs further research
+### References this recipe draws from
 
-Gelatin is an animal-based ingredient. Some might find it problematic to use resources that requires killing an animal because of religious or animal welfare beliefs. Arguments are also made that as long as there's a meat industry, it is better to use product from the entire animal, including skin and bones. Some might consider gelatin to be a product that comes from a waste stream, but this is considered controversial by others.
+- **Biochromes** by Cecilia Raspanti for Fabricademy, Lecture slides, 15 October 2019: [link](https://drive.google.com/file/d/1Ar8j0cJntsFiBxdnrhqTA_9lgDDzB1Wg/view?usp=sharing)
+- **How to make Red Cabbage PH Paper** by Anne Marie Helmenstine for ThoughtCo, 2 February 2020: (https://www.thoughtco.com/make-red-cabbage-ph-paper-605993)
 
-Acrylic (for the mold) is a petrol based plastic but results in very shiny foils and sheets and can be reused endlessly for casting high quality bioplastic sheets.
+### Known concerns and contestations
 
-Using renewable ingredients is not by definition petrol-free. Imagine they have to travel long distances by plane, boat or truck: it takes fuel. Also, the effects of GMO technologies and pesticides can be harmful to the environment and it's worth using knowing the source and production standards involved. If you can afford it, buying organic ingredients is a good starting point.
+The dye might lose its ability to indicate PH because it is not very light fast. It's also not very precies and maybe less over time.  PH of the modifiers might change over time as well, unclear how often they can be reused (further research needed). 
 
 ### Sustainability tags
 
 - Renewable ingredients: yes
-- Vegan: no
-- Made of by-products or waste:  no
+- Vegan: yes
+- Made of by-products or waste:  partially 
 - Biocompostable final product:  yes
-- Reuse: yes, by melting and recasting
+- Reuse: partially, the PH modifiers are re-usable. PH paper is single use only
 
 Needs further research?:  not sure
 
-Gelatine-based bioplastics can be recasted by melting them in a pot with some water. Recycling them with PET plastics contaminates the waste stream. Compost bioplastics in a warm environment with sufficient airflow.
-
 ## Material properties
 
 ### Comparative qualities
-This resin is dense and rather heavy, but not rock hard like synthetic epoxy or cold like glass. It keeps certain level of bounciness to it.
-
-### Technical and sensory properties
-
-- **Strength**: strong
-- **Hardness**: rigid
-- **Transparency**: transparent
-- **Glossiness**: matt
-- **Weight**: heavy
-- **Structure**: closed
-- **Texture**: medium
-- **Temperature**: medium
-- **Shape memory**: high
-- **Odor**: moderate in final product, high during production
-- **Stickiness**: low
-- **Weather resistance:** low
-- **Acoustic properties:** needs further research
-- **Anti-bacterial:** needs further research
-- **Non-allergenic:** needs further research
-- **Electrical properties:** needs further research
-- **Heat resistance:** low
-- **Water resistance:** water resistant
-- **Chemical resistance:** needs further research
-- **Scratch resistance:** moderate
-- **Surface friction:** medium
-- **Color modifiers:** none 
 
+Less precise than litmus paper but precise enough to indicate acidity, neutral or alkaline PH. Might lose its properties as PH indicator over time (needs further research).
 
 ## About this entry
 
@@ -209,7 +175,7 @@ By Cecilia Raspanti, Textile Lab, Waag Amsterdam, 9 March 2020
 
 ### Estimated cost (consumables) in local currency
 
-2,56 Euros for a yield of approx 300 ml
+????? Euros for a yield of approx. 4x 200 ml
 
 ## Copyright information
 
@@ -219,20 +185,20 @@ Yes
 
 ### This recipe was previously published by someone else
 
-Yes, in: **Bioresin (gelatin) Recipe** by Cecilia Raspanti (Textile Lab, Waag), Fabricademy Class "Biofabricating", 2019, [link](https://class.textile-academy.org/classes/week05A/).
+Partially, the PH paper is a variation on **How to make Red Cabbage PH Paper** by Anne Marie Helmenstine for ThoughtCo, 2 February 2020: (https://www.thoughtco.com/make-red-cabbage-ph-paper-605993)
+
 
 ##References
 
-- **The Secrets of Bioplastic** by Clara Davis (Fabtex, IAAC, Fab Lab Barcelona), 2017, [link](https://issuu.com/nat_arc/docs/the_secrets_of_bioplastic_).
-- **The Bioplastics Cookbook: A Catalogue of Bioplastics Recipes** by Margaret Dunne for Fabtextiles, 2018, [link](https://issuu.com/nat_arc/docs/bioplastic_cook_book_3)
-- **Bioresin (gelatin) Recipe** by Cecilia Raspanti (Textile Lab, Waag), Fabricademy Class "Biofabricating", 2019, [link](https://class.textile-academy.org/classes/week05A/).
+- **Biochromes** by Cecilia Raspanti for Fabricademy, Lecture slides, 15 October 2019: [link](https://drive.google.com/file/d/1Ar8j0cJntsFiBxdnrhqTA_9lgDDzB1Wg/view?usp=sharing)
+- **How to make Red Cabbage PH Paper** by Anne Marie Helmenstine for ThoughtCo, 2 February 2020: (https://www.thoughtco.com/make-red-cabbage-ph-paper-605993)
+- **Litmus**, on Wikipedia, n.d.: [link](https://en.wikipedia.org/wiki/Litmus)
+- **Litmus Paper**, on How Product are Made, n.d.:[link](http://www.madehow.com/Volume-6/Litmus-Paper.html)
+- **From alchemy to chemistry**, by Khan Academy's Big History Project, [link](https://www.khanacademy.org/partner-content/big-history-project/stars-and-elements/other-material3/a/from-alchemy-to-chemistry)
 
 ## Images of final product
 
-![](../../images/finalpics-29.jpg)*Bioresin slab, Loes Bogers, 2020*
-
-![](../../images/finalpics-30.jpg)*Bioresin slab, Loes Bogers, 2020*
+![](../../images/finalpics-.jpg)*PH paper and PH modifiers, Loes Bogers, 2020*
 
-![](../../images/finalpics-37.jpg)*Bioresin slab and half dome, Loes Bogers, 2020*