Casting Resin
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Joe Farina
Casting Resin
Sure Colin. But more work needs to be done. Eventually, what I want to see is a standard procedure that everyone could have confidence in. If that happens, it would provide a huge boost to DCG. It's definitely not enough to say that a DCG hologram was "sealed with adhesive between glass." We need to be able to say that a DCG hologram was sealed with X adhesive, with Y pretreatment, following Z protocol. This would then need to be backed up by the results of normal ageing and accelerated ageing. Everyone then could have confidence in the system, including the artist or producer, and the viewer or user.
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Joe Farina
Casting Resin
Tony, I forgot to mention, yes, do whatever you can to make that hologram talk.
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dave battin
Casting Resin
Hi guys , there nothing wrong with real time testing methods as well, Tony that dcg hologram i sent you was sealed in the clear cast resin. I'm sure this material is related to fiberglass as it looks, smells and acts the same as fiberglass resin ........i have had a sample of the resin only glued to a sheet of glass left out side for weeks now with no signs of yellowing/degradation.I originally used this resin to laminate film holograms to glass.
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Joe Farina
Casting Resin
Hey Dave. Yes, polyester casting resin is the same material used in common fiberglass. It's also available from auto supply stores. Marine supply stores also sell fiberglass materials, but often it's an epoxy-based fiberglass system instead of polyester resin. One drawback with common epoxies and polyester resins is that they yellow with age. This takes considerable time, but they do yellow. Since we are dealing with very thin layers sandwiched between glass (that abosorbs UV) the effect may be slowed down quite a bit, which would be a good thing. I guess it's an open question if this yellowing will eventually become objectionable, since the layer is so thin.
But I'm afraid a bigger problem is exposure to long-term high humidity, for polyester resin or simple epoxy systems. There's not much doubt in my mind that both systems will begin to fail when exposed to long-term high humidity, say for example 2 weeks at 80% or above.
At the present time, Hxtal is showing promise. It's made specifically for bonding glass, and is a non-yellowing epoxy with a fairly long track record of use in conjunction with the A-1100 silane. There may be effetive coupling agents for other adhesives like polyester resin, but a problem arises because there is very little documentation out there. It would be a difficult question as to which kind of silane to use.
But I'm afraid a bigger problem is exposure to long-term high humidity, for polyester resin or simple epoxy systems. There's not much doubt in my mind that both systems will begin to fail when exposed to long-term high humidity, say for example 2 weeks at 80% or above.
At the present time, Hxtal is showing promise. It's made specifically for bonding glass, and is a non-yellowing epoxy with a fairly long track record of use in conjunction with the A-1100 silane. There may be effetive coupling agents for other adhesives like polyester resin, but a problem arises because there is very little documentation out there. It would be a difficult question as to which kind of silane to use.
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dave battin
Casting Resin
the yellowing issue will present itself with time, i'm sure. a way around this is to shoot the hologram on the back of the glass (as in a proximity copying) when its sealed in, you wont be seeing thru the glued layer, another little trick the pros have done is to also double dip the edges with an additional coating of epoxy, its like a wearing a belt with suspenders! 
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Dutchelm05
Casting Resin
Joe what would you consider an acceptable lifetime for a DCG hologram? Meaning what is your goal?
If you absolutely love a hologram and stored it in a zip lock bag or in a dessicant filled dry box only taking it out for occational viewing would it last much longer, say 25 years ++?
As far as yellowing, is it light reacting (UV) that would cause it to turn yellow?
As for me, this is a very cheap way to seal average holograms. I will use UV glue or optical glues to seal the good stuff in the rare event that that happens.
Thanks Joe for such a through review of this subject. I learned a lot.
If you absolutely love a hologram and stored it in a zip lock bag or in a dessicant filled dry box only taking it out for occational viewing would it last much longer, say 25 years ++?
As far as yellowing, is it light reacting (UV) that would cause it to turn yellow?
As for me, this is a very cheap way to seal average holograms. I will use UV glue or optical glues to seal the good stuff in the rare event that that happens.
Thanks Joe for such a through review of this subject. I learned a lot.
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holo_cyware
Casting Resin
What I don't understand is why practically nobody but Jeff seems to had tried the extreme dessication method that not only would render the hologram "invincible" to water vapors, but it's also easier. Surely it take patience, but the results are well worth it.
I've been studying this matter for months now, and I know what the best dessicants are. The "damprid" thing is calcium chloride, and this is not a very effective dessicant, but I still think it'll work. The ultimate goal is to lower the water content in the gelatine to under 2%. Jeff described a week in a dessicator over phosphorus pentaoxide (one of the most effective dessicants known, if not THE most effective). So maybe something like 2 weeks should do it.
I've been studying this matter for months now, and I know what the best dessicants are. The "damprid" thing is calcium chloride, and this is not a very effective dessicant, but I still think it'll work. The ultimate goal is to lower the water content in the gelatine to under 2%. Jeff described a week in a dessicator over phosphorus pentaoxide (one of the most effective dessicants known, if not THE most effective). So maybe something like 2 weeks should do it.
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Joe Farina
Casting Resin
It might be good to ponder on the fact that DCG holograms offered for sale are sealed in glass. They don't do this because they enjoy it. I will give just one reason for this. If you have a super-dry (but unsealed) DCG hologram in a cool air-conditioned room, and take it outside in the warm, humid air, moisture will likely condense on it. Bye bye hologram.holo_cyware wrote:What I don't understand is why practically nobody but Jeff seems to had tried the extreme dessication method that not only would render the hologram "invincible" to water vapors, but it's also easier. Surely it take patience, but the results are well worth it.
I've been studying this matter for months now, and I know what the best dessicants are. The "damprid" thing is calcium chloride, and this is not a very effective dessicant, but I still think it'll work. The ultimate goal is to lower the water content in the gelatine to under 2%. Jeff described a week in a dessicator over phosphorus pentaoxide (one of the most effective dessicants known, if not THE most effective). So maybe something like 2 weeks should do it.
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Tony, your question requires a complex answer. It depends on how you intend to use the hologram. I look upon holography as a potential art medium. So, I compare it to other mediums. If I didn't think holograms can compete with other mediums in terms of permanence, then I would personally choose another medium. Take a look at drawing, painting, sculpture, etc. If an artwork is made with reasonable care with regards to material and techniques, it can last a very long time indeed. For an excellent review of this subject, see Ralph Mayer's book: The Artist's Handbook of Materials and Techniques. Or get a good book on art history and take a look at the works, and check the dates to see when they were made.
One snag with DCG holograms in glass is that they can be perceived as being more permanent than they actually are. Since they are sealed in glass, people might regard them as "glass" and store them accordingly. With regards to storage conditions, they really should have the same storage conditions as a drawing on paper, or a painting on canvas. That is to say, normal indoor conditions without any extreme temperature or humidity swings. It's my goal to make DCG holograms as stable as possible, and to try to "make up" for some of the rough treatment that they may receive in the future. Like I've said before on this forum, I don't enjoy this kind of work, and I don't like making things difficult. But after about 30 years of dealing with sealed DCG holograms, I've gotten a little wiser.
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Dutchelm05
Casting Resin
The death watch of my resin cast hologram is still going on.
Sorry no photos but I can say that after a week in water that a two edges are starting to show signs of sepage. It is a 4X5 plate with two corners about 1/2 inches that have disappeared.
This was not present two days ago so in all, not too bad IMO.
I will soak it until it is gone and report back from time to time.
Peace all,
Tony
Sorry no photos but I can say that after a week in water that a two edges are starting to show signs of sepage. It is a 4X5 plate with two corners about 1/2 inches that have disappeared.
This was not present two days ago so in all, not too bad IMO.
I will soak it until it is gone and report back from time to time.
Peace all,
Tony
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Joe Farina
Casting Resin
Thanks for the update, Tony. Considering that I've never heard of using casting resin for this application (except from Dave and you), I would have to say that the results could have been a lot worse. Dunking in liquid water for a long time period is a very severe test.
Another adhesive that I've used in the past is Super Glue Glass Adhesive, which is UV-curing. I am doing a side-by-side test with this (along with the Hxtal) in the 80% humidity enclosure. It's doing surprisingly well, though it is showing signs of de-lamination in some areas. The Hxtal (with silane pretreatment) does not appear to have any damage. The Super Glue Glass adhesive seems to be widely available at stores, and it was used for that little hologram I sent you. By the way, does it have any tiny micro-bubbles along any of the edges? It might take some effort to see them, but they might be visible if you look closely and tilt the hologram in a moderate light.
Making a high-humidity enclosure isn't that hard, incidentally. I took a plastic storage container, like you might find at Wal-Mart, etc., for storing clothes, etc., and put a gallon of water in the bottom. Then I placed a few bricks in the water to serve as a platform. On top of that, I placed a thick piece of plastic (polyethylene cutting board) on which I placed the holograms. (I didn't want the holograms directly on the bricks, since the bricks might soak up water and transfer liquid water to the glass, at least so I thought). Then for the lid, I used a plastic grid that I bought from Home Depot. These grids are used as covers for fluorecsent lighting fixtures. (John mentioned them at some point, for use in his DCG coating station. The only place they seem to have them is at Home Depot.) Anyway, this "grid" served as the lid for the plastic container. To cover the "holes" in the grid, I attached a piece of self-adhesive plastic shelf liner (to the bottom of the "grid lid.") Then, using an X-acto knife, I began removing some of the "squares" of the plastic shelf liner (as defined by the grid) and kept checking the interior of the container with a humidity meter. When I had removed enough squares to maintain approximately 80% RH, I stopped. To make a long story short, I used a container of water with a few holes in the top which let some of the humid air get out, to maintain about 80%.
Another adhesive that I've used in the past is Super Glue Glass Adhesive, which is UV-curing. I am doing a side-by-side test with this (along with the Hxtal) in the 80% humidity enclosure. It's doing surprisingly well, though it is showing signs of de-lamination in some areas. The Hxtal (with silane pretreatment) does not appear to have any damage. The Super Glue Glass adhesive seems to be widely available at stores, and it was used for that little hologram I sent you. By the way, does it have any tiny micro-bubbles along any of the edges? It might take some effort to see them, but they might be visible if you look closely and tilt the hologram in a moderate light.
Making a high-humidity enclosure isn't that hard, incidentally. I took a plastic storage container, like you might find at Wal-Mart, etc., for storing clothes, etc., and put a gallon of water in the bottom. Then I placed a few bricks in the water to serve as a platform. On top of that, I placed a thick piece of plastic (polyethylene cutting board) on which I placed the holograms. (I didn't want the holograms directly on the bricks, since the bricks might soak up water and transfer liquid water to the glass, at least so I thought). Then for the lid, I used a plastic grid that I bought from Home Depot. These grids are used as covers for fluorecsent lighting fixtures. (John mentioned them at some point, for use in his DCG coating station. The only place they seem to have them is at Home Depot.) Anyway, this "grid" served as the lid for the plastic container. To cover the "holes" in the grid, I attached a piece of self-adhesive plastic shelf liner (to the bottom of the "grid lid.") Then, using an X-acto knife, I began removing some of the "squares" of the plastic shelf liner (as defined by the grid) and kept checking the interior of the container with a humidity meter. When I had removed enough squares to maintain approximately 80% RH, I stopped. To make a long story short, I used a container of water with a few holes in the top which let some of the humid air get out, to maintain about 80%.