Facts about Natural glue

[erik winkler]

Glue

Glues of animal origin.
Glues of animal origin such as fish glue, bone glue, hide glue and casein glue.
The first three are based on collagen, the latter based on casein or casein.
Collagen is a protein that is not fit for human consumption, it contains only a few
amino acids, the "building blocks" of proteins and not the eight essential amino acids that we need have.
Collagen is found in bones, bones, skin, tendons, etc.
Especially once they had different methods of collagen out of them and into gelatin, which allows the adhesive strength.
Thus one could kalverbotten from a very good glue and some skins also gave good glue, such as parchment or rabbit skins.
The condition of the raw material required an operation. Vegetable tanned leather was treated differently aluingelooid leather.
Why there are so many different names used to create the glue "glue English", "Leyden glue", "Nerve glue", "native glue", "ermine glue" or "pearl glue".

Isinglass
A special place, the isinglass in: this can be made from carefully cleaned fish waste.
This adhesive has a low gelatin content, but many other proteins.
She is soluble in cold water and, as viscous fluid for sale (order O6355) and is cold processed.
This Isinglass is used where flexibility is desired.
In addition, there are made of isinglass the bladder of the sturgeon.
This is the Isinglass. This is like glue bone glue warm processed.
Isinglass is a very good glue traditionally used in icons used for the gold on wood adhesives.

Casein
Casein is removed from milk by allowing it to curdle. Can serve as rennet or lebferment
acid. It is lebferment from the fourth stomach of a calf taken. Casein is a full phosphorus into protein, it can serve as glue for veneer or as a binder for example, pigments or dyes.
Addition of 5% copper sulphate, the insoluble glue.

Skin and Bone Glue
These are collage adhesives.
Bone is made of several bones and skin glue is made of animal skins, which are soaked in lime. Thereafter, the proteins extracted.
Several extractions done and any extraction gives an adhesive with a specific "Bloom Number".
Bloom Number depends on the gelling ability (the ability of the adhesive to swell) and determines the amount of water to the glue to swell.
An adhesive with a high Bloom Number dries faster but also gives a larger contraction.
Adhesive with a low Numerical Bloom has less water, the glue film is flexible and shrinks less.
By contrast, the longer drying glue, about 2 or 3 days.
Bone has a low Bloom Number.
Previously, the adhesive paste sometimes cast a gauze to dry.
Today is the paste on a heated plate so that the grains are formed and the water evaporates.
You could easily see through what type of glue you had. Now it all grains or beads.
(B) ASIC gelatin from cow hides.
(A) cid gelatin from pig skins.
Amount of water in mL added to 180g adhesive:

Bloom Number water ratio
Water / glue

135 225 1,25:1
192 292 1,62:1
251 360 2,00:1
315 450 2,50:1
379 495 2,75:1

The adhesive must first few hours in cold water swelling and then heated to 60 to 65 ° C.
If the parts are lubricated with the glue cools and forms an adhesive gel.
At that time, the parts are brought together. Than the parts back and forth and then drying the workpiece without clamps, a method mainly used violin makers.
Then the water evaporates leaving a web of collagen fibers occurs, the adhesive strength causes.
There can sometimes be too fast gel formation to occur, this can be delayed by adding urea.
About 3 tablespoons at 250g. Urea does not affect the adhesive strength.
To increase the adhesive strength, 5% water are replaced by a 6% vinegar solution.
A recipe for an adhesive with Bloom's number 135 is:

Glue 180g
212mL water
12ml acetic acid 6%
By adding a few drops of a wetting agent such Surfynol 61, the stronger adhesion and thereby the adhesive strength increases.
Surfynol evaporates completely, formerly or garlic juice was used.
To make skin adhesive insoluble in water 0.25% aluminum sulfate added.
The blending of up to 30% kaolin calculated on the dry weight of adhesive prevents shrinkage of the adhesive.
Keolin, atta clay or attapulgit is a magnesium and aluminum.
Sometimes the glue discolor the wood, then a little titanium dioxide are added.
Even the glue be stained with a 2% dry pigment.
The main component of the adhesive consists of protein.
In order that the product has dried and a preservative is added is the glue very well preserved.
In usable adhesive is a suitable breeding ground for bacteria and fungi.
This allows spoil the glue.
To avoid spoilage, one must:
▪ the adhesive duct cleaning after use and put away dry, because moisture can not micro-organisms live.
· Preferably use sterile water, tap water by boiling it is sterile.
· A solution is not more than 24 hours to keep.
· Not used glue cool and keep closed.
If necessary, 2% hydrogen peroxide (35%) based on the dry matter are added.


Gelatin
Gelatin is like a skin glue and gelatine protein glue of animal material.
In preparation is it just a different approach to the collagen in pure shape.

Starch Adhesives
These adhesives have the origin of starch that can be extracted from wheat, rice or potatoes, etc.
Wheat starch is widely used.
Less: rice starch potato and cornstarch are the glue paste.
Glue based on modified starch take a big place.

[Patrick Mackle]

Erik,
Your post is very informative describing the various glues, their uses, and their origin.
As I read the information I thought I saw at least two Dutch words dropped into the paragraphs and that made
me wonder if you had found this information originally in Dutch and used an interpreter program
or Google translator to convert it into English. If so, I think it worked pretty well.
I really admire your thirst to learn the foundation of materials that are the basis of our beloved craft.
Pat