初次接触乐泰的3536底填胶水是在2008年参与宇龙公司底填胶水竞标时，请参看此文 《LOCTITE 3536 UNDERFILL》。但是只知道此款产品有一个特性据说是可以经过二次回流，客户的理解就是耐热性比较好。 当时此款产品的技术资料也没找到，只是在网上截取了一个产品简介图片。 今天之所以又将此型号摘录下来，一来是因为近日发现此款产品也是属于乐泰公司不多的阳离子体系的底填胶水，大家参看附件的MSDS可略知一二，二来是因为近日参与了一家大公司的底填胶水评估，送了一款阳离子体系的胶水参与评估，表现不大理想。不过阳离子体系的底填胶水兼容性其实真的不大好，早期的有zymet公司的1703系列（那个时候乐泰还没有推出阳离子体系的underfill产品）。仔细的对比了一下乐泰官方版的TDS资料以及当时此产品刚推出时乐泰公司此型号彩页的参数，发现还是几个参数略有调整的，例如粘度、Tg、CTE的参数，也难怪但是乐泰一直没有发布官方的TDS资料了。 后来在网上找到了乐泰在2007年时的3536的内部TDS资料，及官网现在提供下载的TDS资料，这两者没什么区别的。 摘录2007年的TDS如下，有兴趣的朋友去下载附件查看原文：
3536 is a CSP/BGA underfill that is designed to cure quickly at low temperature to minimize thermal stress to other components and provide rapid device throughput. When cured, it provides excellent protection for solder joints against mechanical stress, such as shock, drop, and vibration common in hand-held devices. The material is also reworkable, allowing for recovery of high-cost substrates and PWBs.
Reworkable CSP/BGA Underfill.
PROPERTIES OF UNCURED MATERIAL
Chemical Type Epoxy
Viscosity @ 25°C, mPas, 1,848
PHYSICAL PROPERTIES, CURED MATERIAL
Cure for 60min @ 120°C
Glass Transition, (Tg), °C, by TMA 53
Coefficient of Thermal Expansion cm/cm/°C,
α1 (<Tg) 63 x 10-6
α2 (>Tg) 178 x 10-6
Storage Modulus, GPa 3.5
For safe handling information on this product, consult the
Material Safety Data Sheet (MSDS).
Pot Life @ 25°C, days >14 days
(ITM10T), (time to double in viscosity)
Shelflife @ 2-8°C (estimated), months 6
Optimal Storage: 2-8ºC. Storage at lower than 2°C or higher than 8°C may adversely affect product properties. Material removed from containers may be contaminated during use. Do not return products to the original container. Henkel Corporation cannot assume responsibility for product which has been contaminated or stored under conditions other than those previously indicated. If additional information is required, please contact your local Technical Service Center or Customer Service Representative.
For best results, substrate should be preheated (up to 70°C) to allow fast capillary flow.
Recommended Cure Conditions
5 min. @ 120°C
2 min. @ 130°C
Curing above 140°C is not recommended
The basic removal procedure for 3536 involves heating the underfill to approximately 240°C using a hot air nozzle on standard BGA rework equipment. This component is then twisted and removed. Residue removal is accomplished using a tacky flux or liquid flux and a solder removal vacuum tool.
The data contained herein are furnished for information only and are believed to be reliable. We cannot assume responsibility for the results obtained by others over whose methods we have no control. It is the user’s responsibility to determine suitability for the user’s purpose of any production methods mentioned herein and to adopt such precautions as may be advisable for the protection of property and of persons against any hazards that may be involved in the handling and use thereof. In light of the foregoing, Henkel Corporation specifically disclaims all warranties expressed or implied, including warranties of merchantability or fitness for a particular purpose, arising from sale or use of Loctite Corporation’s products. Loctite Corporation specifically disclaims any liability for consequential or incidental damages of any kind, including lost profits. The discussion herein of various processes or compositions is not to be interpreted as representation that they are free from domination of patents owned by others or as a license under any Loctite Corporation patents that may cover such processes or compositions. We recommend that each prospective user test his proposed application before repetitive use, using this data as a guide. This product may be covered by one or more United States or foreign patents or patent applications.
最后发现了乐泰宣传资料及正式发布的TDS上一个显著的矛盾点， 宣传资料上显示回流炉固化条件可做到150度1分钟，而在正式发布的TDS固化条件中明确强调：“Curing above 140°C is not recommended”。的确阳离子体系产品固化温度过高会产生很多莫名其妙的问题，估计乐泰也是在和客户的配合过程中发现了这个问题，所以在资料里面做了修正。
3536 TDS&MSDS (126.1 KB, 16 次)